TY - CONF A1 - Priebe, Nsesheye Susan A1 - Gluth, Gregor A1 - Simon, Sebastian A1 - Schröder, H.-J. A1 - Kühne, Hans-Carsten T1 - Evaluation of brick clays from various deposits in central Germany for use as SCMs N2 - The development of low carbon cements has gained great importance over the last decades. In the effort to limit the carbon content related to its production, cement is often replaced with supplementary cementitious materials (SCMs). Commonly used SCMs such as fly ash and slag have undergone extensive research, but are currently limited in supply and availability. Among the researched SCMs, calcined clays have proven to be a suitable alternative pozzolan due to their worldwide availability and extremely low calcination temperatures when compared to clinker. This poster presents the results from an ongoing project, aimed at obtaining pozzolans, available in sufficient quantities for Portland-pozzolana cement production in Germany. The poster shows the analyses of seven brick clays from various deposits in central Germany. The chemical and mineral composition of the brick clays was evaluated through inductively coupled plasma – optical emission spectroscopy (ICP-OES), X-ray diffraction (XRD), and thermogravimetric analysis (TG/DTG). The particle size distribution (PSD) was also evaluated by laser granulometry. The results show that the brick clays contain a substantial amount of kaolinite, illite and smectite minerals, the relative proportions differing significantly between deposits. The suitable calcination temperature range of the clays is also evaluated through TG/DTG analysis to obtain the optimum degree of dehydroxylation from which the bricks clays can be suitable for use as a pozzolan. T2 - 2nd International Conference on Calcined Clays for Sustainable Concrete CY - Havana City, Cuba DA - 04.12.2017 KW - Cement KW - CO2 reduction KW - Supplementary cementitious materials KW - Calcined clay KW - Kaolinite KW - Illite KW - Smectite PY - 2017 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. AN - OPUS4-43719 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, R. A1 - Hodoroaba, Vasile-Dan T1 - SEM or TEM for the characterization of nanoparticles? N2 - Scanning Electron Microscopy (SEM) or Transmission Electron Microscopy (TEM) ? This is a question, nowadays discussed in EM labs of research and industry involved in the characterization and metrology of nanoparticles. The Scanning principle is adapted to TEM, the Transmission mode is adapted to Ultra High Resolution SEM. Can modern SEM replace TEM, reach atomic resolution even without Cs corrector or nm lateral resolution for energydispersive X-ray spectroscopy (EDX)? Due to the development of a New Cold Field Emission (NCFE) electron source Hitachi SEMs SU9000 and SU8200 can deliver routinely sub-nm image resolution and EDX mappings at very high count rates and a lateral EDX resolution of a few nm. A TiO2 sample provided by BAM was analysed at 30kV using low kV STEM – simultaneously with the Through-the-lens (TTL) SE detector, the Bright Field transmitted and Dark Field transmitted signals. By this method a pixel precise information of the particles surface using SE, its chemical nature using DF-STEM and its crystalline structure using Bright Field signal is given in one 40sec scan. The advantage of this observation mode compared to Ultra Low Voltage imaging is outlined. T2 - Microscopy Conference 2017 CY - Lausanne, Switzerland DA - 21.08.2017 KW - SEM KW - TEM KW - Nanoparticles PY - 2017 UR - http://www.mc2017.ch/ AN - OPUS4-43890 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reuther, R. A1 - Marvin, H. A1 - Müller, P. A1 - Löschner, K. A1 - Hodoroaba, Vasile-Dan A1 - Stintz, M. A1 - Kammer, F. v. d. A1 - Köber, R. A1 - Rauscher, H. T1 - A new tiered analytical approach and e-Tool for material classification to support the implementation of the EU Nano-Definition N2 - The EC recommendation for the definition of nanomaterial [2011/696/EU] requires the quantitative size determination of constituent particles in samples down to 1 nm. Accordingly, a material is a nanomaterial if 50 % or more of the particles are in the size range 1-100 nm. The fact that engineered nanomaterials already exist in many industrial and consumer products challenges the development of measurement methods to reliably identify, characterize and quantify their occurrence as substance and in various matrices. The EU FP7 NanoDefine project [www.nanodefine.eu] has addressed this challenge by developing a robust, readily implementable and cost-effective measurement strategy to obtain quantitative particle size distributions and to distinguish between nano and non-nano materials according to the EU definition. Based on a comprehensive evaluation of existing methodologies and intra- and inter-lab comparisons, validated measurement methods and instrument calibration procedures have been established to reliably measure the size of particles within 1-100 nm, and beyond, including different shapes, coatings and chemical compositions in industrial materials and consumer products. Case studies prove their applicability for various sectors, including food, pigments and cosmetics. Main outcome is the establishment of an integrated tiered approach including rapid screening (tier 1) and confirmatory methods (tier 2), and a user manual to guide end-users, such as manufacturers, in selecting appropriate methods. Another main product is the “NanoDefiner” e-Tool allowing the standardised / semi-automated selection of appropriate methods for material classification according to the EU definition. Results also contribute to standardization efforts, such as CEN TC 352 or ISO TC 229. T2 - EuroNanoForum 2017 CY - Valletta, Malta DA - 21.06.2017 KW - Nanomaterial classification KW - Nanoparticles KW - EC definition of nanomaterial KW - Tiered approach PY - 2017 UR - http://euronanoforum2017.eu/ AN - OPUS4-43993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haferkamp, Sebastian A1 - Fischer, Franziska A1 - Kraus, Werner A1 - Emmerling, Franziska T1 - In situ monitoring of a mechanochemical Knoevenagel condensation N2 - Mechanaochemistry is an effective method to yield pure compounds within a short reaction time. Mechanochemical C-C bond forming reactions gained increasing interest in the past decade. Among those the Knoevenagel condensation is an important reaction for synthezing a,b-unsaturated compounds. The information on the underlying mechanisms of mechanochemical reactions are scarce. In situ investigations using Raman spectroscopy and synchroton XRD either alone or in combination address this challenge. We present the in situ results of a Knoevenagel condensation with p-nitrobenzaldehyde and malononitrile under neat grinding conditions. T2 - BESSY II User Meeting CY - Berlin, Germany DA - 13.12.2017 KW - Mechanochemistry KW - In situ KW - Knoevenagel condensation KW - C-C coupling PY - 2017 AN - OPUS4-44142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haferkamp, Sebastian A1 - Fischer, Franziska A1 - Kraus, Werner A1 - Emmerling, Franziska T1 - In situ monitoring of mechanochemical Knoevenagel condensations N2 - Mechanaochemistry is an effective method to yield pure compounds within a short reaction time. Mechanochemical C-C bond forming reactions gained increasing interest in the past decade. Among those the Knoevenagel condensation is an important reaction for synthezing a,b-unsaturated compounds. The information on the underlying mechanisms of mechanochemical reactions are scarce. In situ investigations using Raman spectroscopy and synchroton XRD either alone or in combination address this challenge. We present the in situ results of a Knoevenagel condensation with p-nitrobenzaldehyde and malononitrile under neat grinding conditions. T2 - Adlershofer Forschungsforum CY - Berlin, Germany DA - 10.11.2017 KW - Mechanochemistry KW - Knoevenagel condensation PY - 2017 AN - OPUS4-44140 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haferkamp, Sebastian A1 - Fischer, Franziska A1 - Kraus, Werner A1 - Emmerling, Franziska T1 - In situ investigation of a mechanochemical Knoevenagel condensation N2 - Mechanaochemistry is an effective method to yield pure compounds within a short reaction time. Mechanochemical C-C bond forming reactions gained increasing interest in the past decade. Among those the Knoevenagel condensation is an important reaction for synthezing a,b-unsaturated compounds. The information on the underlying mechanisms of mechanochemical reactions are scarce. In situ investigations using Raman spectroscopy and synchroton XRD either alone or in combination address this challenge. We present the in situ results of a Knoevenagel condensation with p-nitrobenzaldehyde and malononitrile under neat grinding conditions. T2 - PRORA CY - Berlin, Germany DA - 30.11.2017 KW - C-C coupling KW - Knoevenagel condensation KW - In situ PY - 2017 AN - OPUS4-44141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koch, Claudia T1 - Standardization in emerging technologies - The case of additive manufacturing N2 - Additive Manufacturing provides an important enabling technology for the digital transformation of the economy. As an emerging technology it has seen a remarkable development over the last three decades. Nevertheless, it is far from a broad adoption with several barriers to overcome yet. One of the major challenges is the lack of standards. The critical role of standardization for innovation is generally recognized, still the topic too often has been neglected in strategic roadmapping exercises for emerging technologies. Too little is known about the complex dynamics and interrelations of standardization and innovation. The anticipation of standardization needs and the timely and efficient implementation of standards is challenging. This paper aims at contributing to a better understanding of the role that standards play in the multi-dimensional system of innovation. It analyzes the trajectories of innovation in Additive Manufacturing in a systematic and holistic way, focusing on standardization activities with regard to coordination, stakeholders involved, the timing and types of standards developed. Putting standardization in context of the multi-dimensional innovation system of Additive Manufacturing the research shows where standards can support the diffusion of an emerging technology. T2 - ITU Kaleidoscope Academic Conference: Challenges for a data-driven society CY - Nanjing, China DA - 27.11.2017 KW - 3D-Printing KW - Additive Manufacturing KW - Emerging technologies KW - Standardization KW - Standards KW - Technological innovation PY - 2017 AN - OPUS4-49082 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Johann, Sergej A1 - Wu, Cheng-Chieh A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Kohlhoff, Harald A1 - Lilienthal, A.J. T1 - Airborne remote gas sensing and mapping N2 - Leaking methane (CH4) from infrastructures, such as pipelines and landfills, is critical for the environment but can also pose a safety risk. To enable a fast detection and localization of these kind of leaks, we developed a novel robotic platform for aerial remote gas sensing. Spectroscopic measurement methods for remote sensing of selected gases lend themselves for use on mini-copters, which offer a number of advantages for inspection and surveillance over traditional methods. No direct contact with the target gas is needed and thus the influence of the aerial platform on the measured gas plume can be kept to a minimum. This allows to overcome one of the major issues with gas-sensitive mini-copters. On the other hand, remote gas sensors, most prominently Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensors have been too bulky given the payload and energy restrictions of mini-copters. Here, we present the Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS), which combines a novel lightweight TDLAS sensor with a 3-axis aerial stabilization gimbal for aiming on a versatile hexacopter. The proposed system can be deployed in scenarios that cannot be addressed by currently available robots and thus constitutes a significant step forward for the field of Mobile Robot Olfaction (MRO). It enables tomographic reconstruction of gas plumes and a localization of gas sources. We also present first results showing its performance under realistic conditions. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) CY - Potsdam, Germany DA - 27.08.2019 KW - Localization of gas sources KW - Mobile Robot Olfaction KW - Tomographic reconstruction of gas plumes KW - Tunable Diode Laser Absorption Spectroscopy (TDLAS) KW - UAV-REGAS PY - 2017 AN - OPUS4-48789 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Asadujjaman, Asad A1 - Ahmadi, Vahid A1 - Yalcin, M. A1 - ten Brummelhuis, N. A1 - Bertin, Annabelle T1 - Functional polymer based on 2,6-diaminopyridine with tunable UCST behaviour in water/alcohol mixture N2 - Thermoresponsive polymers are of great importance in numerous applications such as bioseparation, drug delivery, diagnostic and microfluidic applications.[1-2] Only a few thermoresponsive polymers have been reported that present an Upper Critical Solution Temperature (UCST), i.e. phase separate from solution upon cooling, in a relevant temperature range and “green” solvents such as water or ethanol.[3] Indeed, polymers with UCST behavior below 60°C in alcohol or water/alcohol mixtures are extremely promising for the preparation of “smart” materials for sensing. In this work, two novel functional polymers of based on a 2,6-diaminopyridine motif were synthesized by free-radical polymerization. Their UCST-type transition temperature is tunable by varying either their concentration in solution or the type of solvent. Insights into this phenomenon are investigated using turbidimetry and temperature dependent dynamic light scattering. T2 - Konferenz CY - Lisbon, Portugal DA - 06.03.2017 KW - Thermoresponsive polymers KW - UCST-type polymers PY - 2017 AN - OPUS4-39579 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Asadujjaman, Asad A1 - Wagner, Sabine A1 - Rurack, Knut A1 - Bertin, Annabelle T1 - Switching of nanoparticles' fluorescence between "ON" and "OFF" states by a thermoresponsive polymeric layer N2 - Fluorescent nanoparticles that “light up”/”dim down” by applying external stimuli are of particular interest in the fields of sensing, diagnostics, photonics, protective coatings and microfluidics. The current challenge for these materials is to combine for instance fluorescence and its response to a stimulus such as temperature in a precise manner. Here we present such a system based on a core/shell/shell architecture consisting of a silica core with a fluorescent layer and a thermoresponsive shell. The silica core nanoparticles were first coated with a fluorescent shell using surface initiated reversible addition-fragmentation chain transfer (RAFT) polymerization. The fluorescent nanoparticles were then completely engulfed by a switchable protective coating made of thermoresponsive poly(N-isopropylacrylamide). The fluorescence of the nanoparticles could be “switched on” at room temperature and “switched off” with increasing environmental temperature because of the presence of the thermoresponsive layer. Insights into this phenomenon will be given based on temperature dependent fluorescence measurements and dynamic light scattering. T2 - Hybrid materials Konferenz CY - Lisbon, Portugal DA - 06.03.2017 KW - Core/shell/shell KW - Thermoresponsive polymers KW - Fluorescence materials PY - 2017 AN - OPUS4-39581 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Keller, Julia A1 - Lörchner, Dominique A1 - Koch, Matthias T1 - Simulating biotransformation reactions of citrinin by electrochemistry/mass spectrometry N2 - Mycotoxins can be found worldwide in food and feed and cause a variety of mold-related health risks which makes it necessary to further examine their metabolic fate in human and other mammals. Beside standard in vitro assays with liver cell preparations an increasing interest in new simulation methods are playing a growing role. The online coupling of electrochemistry with mass spectrometry (EC/MS) is one of these novel techniques, successfully applied in pharmacological and drug research for several years now. The primary objective of this study was to investigate the capability of EC/MS to elucidate metabolic pathways of the mycotoxin citrinin as relevant food contaminant. For this purpose, a coulometric flow through cell equipped with a glassy carbon working electrode was used by applying a ramped potential between 0 and 2 V vs Pd/H2. The electrochemically generated oxidation products analyzed by EC/MS were compared to those obtained from in vitro assays. To receive a comprehensive assessment of EC/MS other non-microsomal oxidation techniques such as Fenton-like reaction and UV irradiation were applied. Several hydroxylated derivatives of citrinin were generated by EC/MS and Fenton-like reaction which are similar to microsomal biotransformation products. These data show that EC/MS is a versatile tool that can be easily applied in mycotoxin research to support metabolic investigations of known and unknown mycotoxins. T2 - ANAKON CY - Tübingen, Deutschland DA - 03.04.2017 KW - Electrochemistry KW - Citrinin KW - Mass spectrometry PY - 2017 AN - OPUS4-39765 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rades, Steffi A1 - Ortel, Erik A1 - Wirth, Thomas A1 - Holzweber, Markus A1 - Pellegrino, F. A1 - Martra, G. A1 - Hodoroaba, Vasile-Dan T1 - Tracing fluorine at the surface and in the bulk of TiO2 nanoplatelets by means of SEM-EDX, AES and ToF-SIMS N2 - The synthesis of TiO2 nanoplatelets with fluorine-containing reactants is carried out using titanium (IV) butoxide as precursor and concentrated HF as shape controller, the final product requires a working up in order to eliminate or at least to reduce the amount of residual fluorides, which is realized here by well-defined thermal treatment of the samples. Bulk and surface sensitive methods namely scanning electron microscopy with energydispersive X-ray spectroscopy (SEM-EDX), Auger electron spectroscopy (AES) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) have been applied to trace the presence of any fluorides in dependence on different information depths and measurement sensitivities of these methods. T2 - EMAS 2017 - 15th European Workshop on MODERN DEVELOPMENTS AND APPLICATIONS IN MICROBEAM ANALYSIS and IUMAS-7 Meeting CY - Konstanz, Germany DA - 07.05.2017 KW - Nanoparticles KW - Surface analysis KW - ToF-SIMS KW - AES KW - SEM-EDX PY - 2017 AN - OPUS4-40265 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rades, Steffi A1 - Ortel, Erik A1 - Wirth, Thomas A1 - García, Sarai A1 - Gómez, Estibaliz A1 - Blanco, Miren A1 - Alberto, Gabriele A1 - Martra, Gianmario A1 - Hodoroaba, Vasile-Dan T1 - Surface and in-depth analysis of functionalization of TiO2 nanoparticles for self-assembly in multiple layers N2 - Parameters of TiO2 coatings can greatly influence their final performance in largescale applications such as photocatalytic measurements, orthopedic and/or dental prostheses, cell cultures, and dye-sensitized solar cells. From different film deposition procedures, self-assembly of TiO2 NPs in multiple layers was selected for systematic characterization. EDX, AES and ToF-SIMS analysis have been carried out in order to evaluate the functionalization of several types of TiO2 NPs differing in size, shape and surface area. T2 - EMAS 2017 - 15th European Workshop on MODERN DEVELOPMENTS AND APPLICATIONS IN MICROBEAM ANALYSIS and IUMAS-7 Meeting CY - Constance, Germany DA - 07.05.2017 KW - Functionalization KW - Surface analysis KW - Nanoparticles KW - Thin films PY - 2017 AN - OPUS4-40266 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Mielke, Johannes A1 - Dohányosová, P. A1 - Müller, P. A1 - López-Vidal, S. T1 - Improved Deposition of Nanoparticles vy Electrospray Analaysis with SEM/TEM and EDS N2 - Although there are many experimental techniques for measuring particle sizes and size distributions, electron microscopy (EM) is still considered as the gold standard in this field, especially when it comes to particle sizes in the nanorange (1 nm – 100 nm). Furthermore, high-resolution X-ray spectroscopy (EDS) can be applied to individual nanoparticles. To be able to extract accurate information from the EM micrographs and EDS elemental maps that are representative for the material under investigation, one needs to assure the representativity of the particles as sampled on the substrate and their homogeneous spatial distribution, to avoid operator bias when selecting the imaged area. Furthermore, agglomeration should be avoided as far as possible. Several sample preparation techniques exist since a long time, the most common way being suspending the particles in a liquid and depositing them on the grid. However, this procedure includes the drying of larger solvent amounts on the substrate itself, which can affect the spatial distribution of the deposited particles. One possibility to overcome this problem is the use of an electrospray system, where the suspension of particles is sprayed onto the substrate in charged droplets that are so small that they either dry off on the substrate immediately without affecting the position of particles, or even already during their flight time to the substrate. No dedicated commercial instruments are available for the preparation of TEM grids yet, only electrostatic deposition of aerosols on TEM grids has been reported so far. To test the prototype and assess its performance, several materials have been sprayed onto TEM grids and the resulting particle distributions were compared to more traditional sample preparation strategies like the “drop on grid” method. Operation parameters such as the sample flow-rate, capillary – substrate distance, electric field strength and sampling period length have been optimised. It was found that the particles deposited by electrospray generally show a much more homogeneous spatial distribution on the substrate and a substantial increase of the number of single particles, which are much better suited to an automatic image evaluation procedure than the agglomerated particles observed otherwise. The applicability of the technique to a broad range of materials is demonstrated by various examples, but also the influence of the substrate, the choice of the particular TEM grid, on the obtained spatial particle distribution is assessed. T2 - EMAS 2017 - 15th European Workshop on MODERN DEVELOPMENTS AND APPLICATIONS IN MICROBEAM ANALYSIS and IUMAS-7 Meeting CY - Konstanz, Germany DA - 07.05.2017 KW - Electrospray deposition KW - TEM grids KW - Nanoparticles KW - Agglomeration PY - 2017 AN - OPUS4-40257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tvrdoňová, M. A1 - Ascher, Lena A1 - Jakubowski, Norbert A1 - Vaculovičová, M. A1 - Moravanská, A. A1 - Vaněčková, T. A1 - Vaculovič, T. T1 - A new strategy of reagents labeling (NPs) used in immunoassay with LA-ICP-MS N2 - Laser ablation with inductively coupled plasma is still more used in life science as biology and biomedicine and the utilization of metals and proteins determination simultaneously is also growing up. We have developed a new strategy of labeling of antibody (it can specific binds to proteins) by nanoparticles and quantum dots which is composed of thousands of atoms and thus increases the sensitivity enormously and of course decreases the Limit of detection, compare to lanthanoids labeling. The ability of successfully tagged antibodies bound to Antigen (protein) was proved by dot blot on membrane imaged by LA-ICP-MS. T2 - Euroanalysis 2017 CY - Stockholm, Sweden DA - 28.08.2017 KW - Immunoassay KW - LA-ICP-MS KW - Labeling KW - Nanoparticle PY - 2017 AN - OPUS4-43168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rühlmann, Madlen A1 - Büchele, Dominique A1 - Ostermann, Markus A1 - Schmid, Thomas T1 - Determination of plant essential nutrients in soils using DP-LIBS N2 - LIBS (laser-induced breakdown spectroscopy) is known as a fast and simultaneous multi-element analysis with little or no sample preparation. In the last few years there has been a growing interest in applications of LIBS in the field of agriculture. As part of the National Research Strategy BioEconomy 2030 the German Federal Ministry of Education and Research (BMBF) started an innovation programme called BonaRes. BonaRes consists of ten interdisciplinary research project associations which are dealing with soil as a sustainable resource for the bio-economy. One of these research projects is I4S (intelligence for soil) which has the goal to develop an integrated system for site-specific soil fertility management. This system includes a sensor platform, which contains different sensors, like XRF, VIS-NIR, Gamma and LIBS. The main task of LIBS measurements in this project is the real time determination of the elemental contents of nutrients in soils, like calcium, magnesium, potassium. For this purpose, a special setup has been designed. The sample uptake operates with the help of a rotatable sample plate which circulates with different velocities to simulate the application on the field. To provide a higher intensity and a better reproducibility of the obtained signal, a double-pulse Nd:YAG laser was used. In order to minimize dust formation from the soil during the operation of the laser, a dust removal by suction has been integrated. When using relative methods such as LIBS, a suitable calibration curve is needed for absolute quantification. With the help of 16 certified reference soils, calibration curves for different elements were initially calculated and used for the quantification of seven soil samples from different testing grounds in Germany. The complex matrix of soils, as well as the influence of moisture and grain size in soils makes the absolute quantification by LIBS challenging. To overcome these influences, a calibration curve based on multivariate analysis (partial least square regression) was generated. T2 - Adlershof Forschungsforum CY - Berlin, Germany DA - 10.11.2017 KW - Fertility management KW - Multivariate KW - Soil KW - LIBS PY - 2017 AN - OPUS4-43154 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gawlitza, Kornelia A1 - Bartelmeß, Jürgen A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Johann, Sergej A1 - Tiebe, Carlo A1 - Banach, Ulrich A1 - Noske, Reinhard A1 - Rurack, Knut T1 - Fluorescence sensor for the long-term monitoring of gaseous ammonia N2 - Ammonia and its reaction products can cause considerable damage of human health and ecosystems, increasing the necessity for reliable and reversible sensors to monitor traces of gaseous ammonia in ambient air directly on-site or in the field. Although various types of gas sensors are available, fluorescence sensors have gained importance due to advantages such as high sensitivity and facile miniaturization. Here, we present the development of a sensor material for the detection of gaseous ammonia in the lower ppm to ppb range by incorporation of a fluorescent dye, which shows reversible fluorescence modulations as a function of analyte concentration, into a polymer matrix to ensure the accumulation of ammonia. A gas standard generator producing standard gas mixtures, which comply with the metrological traceability in the desired environmentally relevant measurement range, was used to calibrate the optical sensor system. To integrate the sensor material into a mobile device, a prototype of a hand-held instrument was developed, enabling straightforward data acquisition over a long period. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Ammonia gas sensor KW - Fluorescence KW - Air quality monitoring KW - Standard gas generator KW - Miniaturized sensor device PY - 2017 AN - OPUS4-43143 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heinrich, Thomas A1 - Hupatz, H. A1 - Lippitz, Andreas A1 - Schalley, C. A1 - Unger, Wolfgang T1 - NEXAFS and XPS investigations of a dual switchable rotaxane multilayer N2 - A multilayer consisting of two different rotaxanes was investigated with different analytical methods. The rotaxanes can be switched with two different stimuli - chemical and photochemical. XPS indicates that our layer-by-layer approach worked and a layer growth with every deposition step is present. NEXAFS showed that both stimuli cause an increase of the multilayer's preferential orientation. T2 - BESSY User Meeting CY - Berlin, Germany DA - 13.12.2017 KW - NEXAFS KW - XPS KW - Rotaxanes PY - 2017 AN - OPUS4-43616 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sobol, Oded A1 - Steiner, S. A1 - Albe, K. A1 - Froemling, T. A1 - Unger, Wolfgang T1 - The characterization of oxygen diffusion in (Na1/2Bi1/2)TiO3 piezo-ceramics by Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) N2 - The ferroelectric ceramic NBT and its solid solutions with barium titanate (BT) are examples for the most promising lead free materials to substitute the dominant Pb(Zr,Ti)O3 (PZT). Lead based material should generally be disregarded due to environmental and health reasons. However, there is no class of lead-free piezoelectric materials that can replace PZT entirely. Not only the often inferior ferroelectric properties but also the lack of understanding of the defect chemistry of NBT is still a challenge for the replacement of lead containing piezo-ceramics. Just recently it could be shown by Li et al. that NBT obtains extraordinarily high oxygen ionic conductivity when doped with Mg as acceptor. It was actually expected that doping just leads to a hardening of the ferroelectric properties. However, it became clear that the known defect chemical behavior of PZT cannot be extrapolated to NBT materials. Hence, to gain information on general doping effects a better defect chemical investigation is needed. This is particularly important for the applications with high reliability demands to investigate possible degradation and fatigue mechanisms. In the present work Time-of-flight-secondary ion mass spectrometry (ToF-SIMS) was used in order to observe the influence of different acceptor dopants (Fe, Ni, Al) on the oxygen diffusion in NBT. ToF-SIMS holds the ability to gain a full elemental distribution in a sub-micron resolution and was therefore chosen to provide the essential information on the favorable diffusion paths of oxygen in NBT in dependence of the chosen doping element. 18O was used as a tracer for oxygen as its natural abundance is only 0.2%. The doped NBT samples have been annealed for 5 h at 500°C in a 0.2 bar 18O-tracer atmosphere to be able to detect oxygen ion diffusion. ToF-SIMS investigations were conducted on a ToF-SIMS IV (ION TOF GmbH, Münster, Germany) using a Bi+ primary ion beam (25KeV in collimated burst alignment mode with a beam diameter of ~150 nm) and a Cs+ sputter beam (3KeV). The results illustrate the different impact of dopants on the diffusion properties which is evidence for a highly non-linear dependence on dopant type and concentration. T2 - 21st International Conference on Secondary Ion Mass Spectrometry - SIMS21 CY - Krakow, Poland DA - 10.09.2017 KW - ToF-SIMS KW - NBT KW - Piezoceramics PY - 2017 UR - http://sims.confer.uj.edu.pl/boa_poster.php?id=93 AN - OPUS4-42911 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Laquai, René A1 - Müller, Bernd R. A1 - Kasperovich, G. A1 - Haubrich, J. A1 - Requena, G. A1 - Bruno, Giovanni T1 - Distinguishing characteristic defect in additively manufactured Ti-Al6-V4 with synchrotron X-ray refraction radiography N2 - Synchrotron X-ray refraction radiography (SXRR) is proven to identify different kinds of defects in Ti-Al6-V4 samples produces by selective laser melting. Namely, these defect types are empty pores and unprocessed powder, which are characteristic to the regions above and below the optimal laser energy density, respectively. Furthermore, SXRR detects small defects below the spatial resolution. T2 - BESSY User Meeting CY - Berlin, Germany DA - 13.12.2017 KW - Additive manufacturing KW - X-ray refraction KW - Porosity PY - 2017 AN - OPUS4-43446 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kjaervik, Marit A1 - Seim, C. A1 - Streeck, C. A1 - Wansleben, M. A1 - Hornemann, A. A1 - Schwibbert, Karin A1 - Unger, Wolfgang A1 - Vorng, J. L. A1 - Kästner, B. A1 - Dietrich, P. A1 - Thissen, A. A1 - Beckhoff, B. T1 - EMPIR project Metrology vs. Bad Bugs aims to provide urgently needed metrology to quantitatively measure localization and penetration of antibiotics and biocides in bacteria and biofilms N2 - An overview of ongoing reference-free X-ray spectrometry, near-ambient pressure X-ray photoelectron spectroscopy and Fourier-Transform infrared micro-spectroscopy studies on the penetration of biocides/antibiotics into bacteria and biofilms is given. T2 - Ninth Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 13.12.2017 KW - Biofilms KW - Alginate KW - XRF KW - FTIR KW - NAP-XPS PY - 2017 AN - OPUS4-43465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Donsky, I. S. A1 - Lippitz, Andreas A1 - Adeli, M. A1 - Haag, R. A1 - Unger, Wolfgang T1 - 2D nanomaterials with switchable pathogen binding N2 - Graphene derivatives have shown great promise in the field of pathogen binding and sensing. Due to their diverse applications, they show a variety of activities that range from bacterial adhesion to bacterial resistance. Therefore, domination of the graphene-pathogen interactions is highly relevant for producing 2D platforms with the desired applications. In order to gain control over the interactions between graphene and biosystems, mechanisms should be fully understood. The surface functionality of graphene is one of the most important factors that dominates its interactions with biosystems and pathogens. Covalent functionalization is a robust method through which functionality, chemical structure, and subsequently physicochemical properties of graphene are abundantly manipulated. A critical issue for preparing graphene-based 2D materials with a defined surface structure, however, is controlling the functionalization in terms of number, position, and type of functional groups. T2 - 9th Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 13.12.2017 KW - Graphene KW - Functionalization KW - XPS KW - C Kedge NEXAFS PY - 2017 AN - OPUS4-43456 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishurova, Tatiana A1 - Thiede, Tobias A1 - Cabeza, Sandra A1 - Bruno, Giovanni A1 - Kromm, Arne A1 - Nadammal, Naresh T1 - The influence of the support structure on residual stress and distortion in SLM Inconel 718 parts N2 - The effect of support structure and of removal from the base plate on the residual stress state in Selective Laser Melted IN718 parts was studied by means of synchrotron X-ray diffraction. The residual stresses in subsurface region of two elongated prisms in as-built condition and after the cutting from the base plate were determined. One sample was directly built on a base plate and another one on a support structure. Also, the distortion on the top surface due to stress release was measured by contact profilometry. High tensile residual stress values were found, with pronounced stress gradient along the hatching direction. In the sample on support stress redistribution took place after removal of the base plate, as opposed to simple stress relaxation for the sample without support. The sample on support structure showed larger distortion compared to sample without support. We conclude that the use of a support decreases stress values but stress relieving heat treatments are still needed. T2 - User Meeting HZB 2018 CY - Berlin, Germany DA - 14.12.2017 KW - Additive manufacturing KW - Selective laser melting KW - Residual stress KW - Synchrotron X-ray diffraction PY - 2017 AN - OPUS4-43460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Anja A1 - Lippitz, Andreas A1 - Dörfel, I. A1 - Ritter, B. A1 - Kemnitz, E. A1 - Unger, Wolfgang T1 - Quantitative chemical depth-profiling by synchrotron-radiation-XPS: Investigation of SrF2-CaF2 core-shell nanoparticles N2 - SrF2 nanoparticles can be doped with trivalent earth metal ions such as Eu3+ and Tb3+ to generate materials exhibiting an intensive red or green fluorescence. A CaF2 shell increases intensity, fluorescence lifetie and quantum yield. The chemical composition of the nanoparticle core-shell region is investigated by XPS at different excitation energies corresponding to different information depths. T2 - Ninth Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 13.12.2017 KW - Core-shell nanoparticles KW - Synchrotron-XPS KW - Depth-profiling PY - 2017 N1 - Geburtsname von Müller, Anja: Hermanns, A. - Birth name of Müller, Anja: Hermanns, A. AN - OPUS4-43464 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kulla, Hannes A1 - Becker, Christian A1 - Casati, Nicola A1 - Paulus, Beate A1 - Rademann, Klaus A1 - Emmerling, Franziska T1 - In situ PXRD monitoring of a mechanochemical cocrystal formation in milling jars of different material N2 - We present an in situ PXRD investigation of the mechanochemical cocrystal formation of pyrazinamide with pimelic acid in two milling jar materials. In the steel jar a polymorph transformation presenting an exception of Ostwald’s rule of stages is observed. T2 - BESSY User Meeting 2017 CY - Bessy II (HZB), Berlin, Germany DA - 14.12.2017 KW - In situ KW - XRD KW - Polymorph KW - Cocrystal KW - Milling PY - 2017 AN - OPUS4-43502 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emmerling, Franziska A1 - Kulla, Hannes A1 - Wilke, Manuel T1 - In situ investigations of mechanochemical reactions - new insights in formation pathways N2 - Mechanochemistry is increasingly used for synthesizing soft matter materials including metal organic compounds and cocrystals. The ever-increasing interest in this method is contrasted by a limited mechanistic understanding of the mechanochemical reactivity and selectivity. Time-resolved in situ investigations of milling reactions provide direct insights in the underlying mechanisms. We recently introduced a setup enabling in situ investigation of mechanochemical reactions using synchrotron XRD combined with Raman spectroscopy. The specific combination allows to study milling processes comprehensively on the level of the molecular and crystalline structure and thus obtaining reliable data for mechanistic studies. In situ Raman spectroscopy coupled with thermography revealed a low temperature increase during milling reactions due to the mechanical impact and clear temperature increases because of the reaction heat. Based on the data, temperature rises as postulated in the magma plasma and hot spot theory can be excluded for soft matter milling syntheses. Our results indicate that in situ investigation of milling reactions offer a new approach to tune and optimize mechanochemically synthesized compounds. T2 - Wissenschaftsforum Chemie CY - Berlin, Germany DA - 10.09.17 KW - Mechanochemistry KW - In situ PY - 2017 AN - OPUS4-43563 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Keller, Julia A1 - Haase, H. A1 - Koch, Matthias T1 - Electrochemistry coupled with LC/MS for production and characterization of mycotoxin oxidation products N2 - Mycotoxins cause a variety of mold-related health risks which makes it necessary to further examine their metabolic pathways in human and other mammals. Beside standard in vitro assays with liver cell microsomes an increasing interest in new and rapid simulation techniques are playing a growing role in mycotoxin research. Herein, the coupling of electrochemistry with liquid chromatography and mass spectrometry (EC/LC/MS) is presented as fast and simple method to investigate the oxidative fate of mycotoxins. For this case study, two food relevant mycotoxins (zearalenone and citrinin) were selected. Experiments were performed by using an electrochemical flow through cell integrated in the flow path of the autosampler of the chromatographic system. The reaction mixture was separated by a RP-C18 column and analyzed by a single quadrupole MS (Figure 1). Oxidation products were generated by applying potentials of 400, 800, 1200 and 1600 mV vs Pd/H2 using a glassy carbon working electrode. Different oxidation reactions like hydroxylation, dehydrogenation and dimerization lead to a diverse product pattern of the investigated mycotoxins. In a comparative study, electrochemical generated reaction products were compared with metabolites produced by human and rat liver microsomes in vitro. The obtained data show that EC/LC/MS is a versatile and promising tool in mycotoxin research to support metabolic investigations of known and unknown mycotoxins. T2 - Tag der Chemie CY - Berlin, Germany DA - 03.07.2017 KW - Electrochemistry KW - Mycotoxins PY - 2017 AN - OPUS4-42980 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Iznaguen, Hassan A1 - Piechotta, Christian A1 - Ostermann, Markus A1 - Traub, Heike T1 - Homogeneity of dispersed brominated flame retardants (HBCD) in polystyrene by LA-ICP-MS and XRF N2 - To investigate the release or migration of flame retardants from polypropylene (PP) and polysytrene (PS) samples with a defined content of flame retardants as additives were prepared and used. Therefore a distinct 1,2,5,6,9,10-hexabromocyclododecane HBCD concentration of 1 wt.% in PS resp. a specified bromodiphenylether (BDE-209) of 0.1 wt.% in PP is defined. For the preparation of the samples granular PP or PS are extruded together with the BFR additives. Even the result of this process may lead to homogenous partitions of the BFR additives. So, the distribution of these additives must be proven before using the samples in an experimental setup for weathering studies. In accordance to the regulation of RoHS (2011/65/EU) , where the use of XRF is recommended for the proof of flame retardants in electronic consumer products, we use this method as a reference to the laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Therefore we present the correlation of these experiments. The experimental setup for the XRF experiment is like a standard addition: in cavities, which are introduced in the sample plates subsequently, solutions of defined concentration of flame retardants are put in there. According to the idea of standard addition, we get an information of the originating mass fraction of flame retardant in each sample and we can monitor the release and migration of these additives during/after the weathering experiments with high precision. An internal standard of HBCD is added as a marker and can be analyzed after the weathering experiment. T2 - 8th European Weathering Symposium EWS CY - Wien, Austria DA - 20.09.2017 KW - LA-ICP-MS KW - XRF KW - BFR PY - 2017 AN - OPUS4-43313 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gawlitza, Kornelia A1 - Tiebe, Carlo A1 - Banach, Ulrich A1 - Noske, Reinhard A1 - Bartholmai, Matthias A1 - Rurack, Knut T1 - Novel sensor for long-term monitoring of ammonia in gas phase N2 - Pollution through emission of toxic gases is of utmost environmental concern, raising the interest in developing reliable gas sensors. Exemplarily, ammonia and its conversion products can provoke considerable damage on human health and ecosystems. Hence, there is a need for reliable and reversible sensor materials to monitor traces of gaseous ammonia in ambient air, which at best can be used on-site for field measurements. Although various types of sensors such as potentiometric, amperometric, and biological sensors are available for detecting trace amounts of gases, fluorescent sensors have gained importance due to several advantages such as high sensitivity, possible miniaturization, as well as potential multiplexing. Herein, we present the development of a sensor material for gaseous ammonia in the lower ppm or even ppb range using optical fluorescence as transduction mechanism due to its intrinsically high sensitivity and high spatial resolution.[1] Therefore, a fluorescent dye, which shows reversible fluorescence enhancement in the presence of the analyte was incorporated into a polymer matrix, the latter to ensure the accumulation of ammonia. To calibrate the designed optical sensor system a gas standard generator was used, producing standard gas mixtures, which comply with the metrological traceability for ammonia gas standards in the desired environmentally relevant measurement range.[2] Beside the development of a highly sensitive, selective, and reversible sensor, the integration of such systems into mobile sensor devices is addressed. Therefore, a prototype of a miniaturized hand-held instrument was developed enabling a straightforward and long-term read-out of the measurement signal. T2 - 13. Dresdner Sensor Symposium (13. DSS) CY - Dresden, Germany DA - 04.12.2017 KW - Ammonia gas sensor KW - Fluorescence KW - Air quality monitoring KW - Standard gas generator KW - Minitaurized sensor device PY - 2017 AN - OPUS4-43351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo A1 - Banach, Ulrich A1 - Hübert, Thomas A1 - Gawlitza, Kornelia A1 - Bartholmai, Matthias T1 - Development of a gas standard generator N2 - Pollution through emission of toxic gases is an increasing problem for the environment. It affects similarly agricultural, industrial and urban areas. In future, environmental emissions in ambient air must be monitored at even lower concentrations as nowadays. One environmental relevant compound is ammonia and its conversion product ammonium that have strong negative impact on human health and ecosystems. Most ammonia measurements in ambient air are performed in the range below 1000 nmol·mol-1 and thus there is a need for reliable traceable ammonia gas standards and in addition in situ analytical procedures for monitoring (in ambient air to avoid that thresholds are exceeded). Therefore, the use of reference materials is necessary for development accompanying test or for calibration, e. g. of structure-integrated sensors and mobile multi-gas sensors. The developed gas standard generator produces gas mixtures that comply with the metrological traceability for ammonia gas standards in the desired environmentally relevant measurement range. The method is based on the permeation of ammonia through a membrane at constant temperature and pressure. The resulting ammonia penetrant gas flow is then mixed with a carrier gas flow to generate a gas standard flow of known concentration. The dynamic rage is enlarged by using a two dilution steps. Depending on the permeation rate, generable molar fractions are possible in the range nmol·mol-1 to a few µmol·mol-1. We present the design of an ammonia gas standard generator and first results of the characterisation of its individual components supporting the uncertainty assessment according to GUM for stable gas concentrations in this range. The relative uncertainty of the generated ammonia gas standard is smaller than 4 % (k = 2). T2 - Colloquium of Optical Spectrometry (COSP) CY - Berlin, Germany DA - 27.11.2017 KW - Gas standard generator KW - Permeation method KW - Ammonia PY - 2017 AN - OPUS4-43337 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Improved traceability chain of nanoparticle size measurements N2 - The overall objective of project Improved traceability chain of nanoparticle size measurements is to improve the traceability chain for nanoparticle size measurements. The main impact will be achieved by manifold contributions to standard documents for CEN/TC 352 “Nanotechnologies”, which directly addresses the research needs of CEN, CENELEC and ETSI mandated by EC to develop standards for methods and reference materials to accurately measure the size and size distribution of nanoparticles. This will take place in collaboration with ISO/TC229 ‘Nanotechnologies’, ISO/TC24/SC4 ‘Particle characterization’ and ISO/TC201 ‘Surface analysis’/ SC9 ‘Scanning probe microscopy’. T2 - EMPIR 2017 Review Conference CY - Monaco DA - 9.11.2017 KW - Nanoparticles KW - Traceability KW - Electron micrsocopy KW - Size KW - Shape PY - 2017 AN - OPUS4-43019 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zavoiura, Oleksandr A1 - Resch-Genger, Ute A1 - Seitz, O. T1 - RNA detection by FRET systems based on peptide nucleic acid-QD conjugates N2 - Today, 40 % of the world’s population live in areas with a significant risk of dengue infection. Early and reliable diagnosis of dengue virus (DENV) is essential to provide the patients with the required medical care and prevent spreading of the disease. Conventional methods for DENV diagnosis like PCR and virus isolation can be used in laboratory settings, yet are difficult to implement in point-of-care diagnostics, requiring simple, selective, fast, and sensitive detection schemes. We present here a novel approach for the detection of DENV, via its RNA, with optical read-out that relies on RNA-catalyzed fluorophore transfer onto a semiconductor quantum dot (QD) and Förster resonance energy transfer (FRET). For this RNA assay, peptide nucleic acid (PNA) oligomers were used as highly specific capture and reporter probes. PNA exhibits remarkable affinity towards RNA as well as extremely high chemical and enzymatic stability. The capture probe, which is immobilized on a QD acting as FRET donor, bears a nucleophile at the N-terminus and the reporter probe is modified with an organic dye acting as FRET acceptor. The presence of DENV genomic RNA in the sample triggers a transfer of the dye onto the QD, signaled by FRET between the QD and the dye. A unique advantage of this system is the ability of one RNA molecule to trigger multiple transfer reactions, thereby amplifying the fluorescence signal. This assay together with the exceptional brightness of QDs and outstanding hybridization properties of PNA allows for highly specific and sensitive detection of DENV RNA in the sub-nM range. T2 - MAF 2017 CY - Brügge, Belgium DA - 10.09.2017 KW - QD KW - RNA detection KW - PNA KW - Click chemistry PY - 2017 AN - OPUS4-43230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hiller, Th. A1 - Costabel, S. A1 - Müller-Petke, M. A1 - Kruschwitz, Sabine T1 - Evaluation of different laboratory NMR devices in a tripartite round robin test N2 - Nuclear magnetic resonance (NMR) is a well established laboratory / borehole method to characterize the storage and transport properties of rocks due to its direct sensitivity to the corresponding pore fluid saturation (water or oil) and pore sizes. For petrophysical applications there are several different NMR laboratory devices commercially available varying over a wide range of e.g. magnetic field strength / frequency (2 MHz to 30 MHz), applicable measurement protocols (T1, T2, T1-T2, T2-D, etc.) and sample sizes (2.5 cm to 10 cm in diameter). In this work we present NMR measurements, layed out in a round robin like manner, on a set of 20 sandstone samples. We use three different NMR devices containing two standard setups with homogenous magnetic fields (LIAG and RWTH) and one single-sided setup with gradient field (BGR) to measure T1 and T2 relaxation data. In our evaluation we especially focus on the comparison of the individually inverted relaxation time distributions to quantify the differences arising from different laboratory setups. Diverging results can be deduced on the one hand to the inherit differences between homogeneous and gradient fields but on the other hand also due to quality differences between the two homogeneous setups. Additionally, we also examine the influence of the individually chosen inversion parameters (signal processing, distribution sampling points, error weighting, regularization, etc.) to establish a general standardized best practice recommendation for future petrophysical NMR laboratory measurements. T2 - 77. Jahrestagung der Deutschen Geophysikalischen Gesellschaft CY - Potsdam, Germany DA - 27.03.2017 KW - Nuclear Magnetic Resonance KW - Sandstone PY - 2017 AN - OPUS4-43244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Tiebe, Carlo A1 - Gawlitza, Kornelia A1 - Bartelmeß, Jürgen T1 - Adaptable multi-sensor device for gas detection N2 - Innovation is the catalyst for the technology of the future. It is important to develop new and better technologies that can continuously monitor the environmental impact, e.g., for air quality control or emission detection. In the recently at BAM developed Universal Pump Sensor Control (UPSC3) module, different components and sensors are fused. The combination of the individual components makes the UPSC3 module an excellent monitoring and reference system for the development and characterization of gas specific sensors. Measurements over long periods are possible, for mixed gas loads or for certain gas measurements. The system is part of a mobile sensor network of several sensor units, which can also be used as standalone systems. The motivation and objective of this research is to develop gas sensors based on fluorescence detection with range of ppm / ppb. For this task a reference system is required, which contains volatile organic compound (VOC) sensors for reference data from different scenarios. The integrated multi-sensor unit can measure different gases through the integrated 3-fold VOC sensor, which can be adapted to the addressed scenario. . The system-integrated flow control, with pump and flow sensor, allows the gas molecules to be transported directly to the VOC sensor. The entire measurement is permanently stored on an integrated memory card. If the previously determined limit range is exceeded, an alarm is generated. The system is an important tool towards further developments in the field of gas sensors and is primarily used for the validation of chemically based gas sensors. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Gas detection KW - Multi sensor device KW - Pump control KW - VOC PY - 2017 AN - OPUS4-43193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Johann, Sergej A1 - Tiebe, Carlo A1 - Gawlitza, Kornelia A1 - Bartelmeß, Jürgen A1 - Bartholmai, Matthias A1 - Hüllmann, Dino A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Kohlhoff, Harald A1 - Lilienthal, A.J. T1 - Airborne Remote Gas Sensing and Mapping N2 - Leaking methane (CH4) from infrastructures, such as pipelines and landfills, is critical for the environment but can also pose a safety risk. To enable a fast detection and localization of these kind of leaks, we developed a novel robotic platform for aerial remote gas sensing. Spectroscopic measurement methods for remote sensing of selected gases lend themselves for use on mini-copters, which offer a number of advantages for inspection and surveillance over traditional methods. No direct contact with the target gas is needed and thus the influence of the aerial platform on the measured gas plume can be kept to a minimum. This allows to overcome one of the major issues with gas-sensitive mini-copters. On the other hand, remote gas sensors, most prominently Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensors have been too bulky given the payload and energy restrictions of mini-copters. Here, we present the Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS), which combines a novel lightweight TDLAS sensor with a 3-axis aerial stabilization gimbal for aiming on a versatile hexacopter. The proposed system can be deployed in scenarios that cannot be addressed by currently available robots and thus constitutes a significant step forward for the field of Mobile Robot Olfaction (MRO). It enables tomographic reconstruction of gas plumes and a localization of gas sources. We also present first results showing its performance under realistic conditions. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Tunable Diode Laser Absorption Spectroscopy (TDLAS) KW - UAV-REGAS KW - Mobile Robot Olfaction KW - Tomographic reconstruction of gas plumes KW - Localization of gas sources PY - 2017 AN - OPUS4-43204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartelmeß, Jürgen A1 - Gawlitza, Kornelia A1 - Bartholmai, Matthias A1 - Rurack, Knut A1 - Kohlhoff, Harald A1 - Kraus, Werner A1 - Mansurova, Maria A1 - Bell, Jérémy T1 - Developments towards the fluorescence based sensing of hazardous gases N2 - Fluorescence based sensing is a versatile approach for the trace analysis outside of the laboratory, requiring suitable sensor materials and their integration into sensing devices. The versatility of fluorophores as probes, especially in terms of the possibility to tailor their optical as well as their recognition properties by synthetic modifications in a wide range, renders them a superior active component for the preparation of optical sensor devices. Recent works at BAM in this field include, for example, the detection of nerve gas agents, illustrating impressively the aforementioned benefits of fluorophores in optical sensing applications. In the interdisciplinary approach presented here, we target hazardous gases such as ammonia, benzene, and hydrogen sulfide, next to others, which pose a major threat to human health and environmental safety and for which the availability of a sensitive and reliable detection method is highly desirable. The dyes presented follow a “turn-on” fluorescence schematic which allows for the selective and sensitive detection of the respective gaseous analyte. The immobilization of the probe in polymeric matrices is then the next step toward the fabrication of a prototype device for molecular sensing. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Gas sensing KW - Fluorescence KW - KonSens PY - 2017 AN - OPUS4-43209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kraft, Marco A1 - Würth, Christian A1 - Kaiser, Martin A1 - Muhr, V. A1 - Hirsch, T. A1 - Resch-Genger, Ute T1 - Particle size dependent optical properties of hexagonal β-NaYF4: 2 % Er3+, 20 % Yb3+ upconversion nanoparticles in cyclohexane and water N2 - Hexagonal NaYF4 doped with 20 % Yb3+ and 2 % Er3+ is an efficient upconversion (UC) phosphor for the conversion of 976 nm excitation light to emission at 845 nm, 800 nm, 655 nm, 540 nm and 410 nm light. The emission behavior of nanoparticles made from this material is strongly influenced by particle size, surface chemistry, and microenvironment. Furthermore their UC emission originates from multiphotonic absorption processes, rendering the resulting luminescence spectra and intensities excitation power density (P) dependent. Therefore the rational design of efficient nm-sized UC particles e.g., for applications in the material and life sciences requires reliable spectroscopic tools for the characterization of the optical properties of these materials like the excitation power density (P)-dependent UC quantum yield (QYUC) in dispersion, which presents a measure for the efficiency of the conversion of absorbed into emitted photons. Up to date the P-dependent absolute measurement of QYUC in aqueous media with an excitation wavelength of 976 nm presents a considerable challenge due to the low absorption coefficients of the UC materials and the absorption of water at this wavelength. T2 - International Conference on Advanced Materials and Nanotechnology CY - Queenstown, New Zealand DA - 12.02.2017 KW - Upconversion KW - Quantum yield KW - Lifetime KW - Water KW - Cyclohexane PY - 2017 AN - OPUS4-40093 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lauer, Franziska A1 - Seifert, Stephan A1 - Kneipp, Janina A1 - Weidner, Steffen T1 - Simplifying the preparation of pollen samples for MALDI-TOF MS classification N2 - Matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) is a well-implemented analytical technique for the investigation of complex biological samples. In MS, the sample preparation strategy is decisive for the success of the measurements. Here, sample preparation processes and target materials for the investigation of different pollen grains are compared. A reduced and optimized sample preparation process prior to MALDI-TOF measurement is presented using conductive carbon tape as target. The application of conductive tape yields in enhanced absolute signal intensities and mass spectral pattern information, which leads to a clear separation in subsequent pattern analysis T2 - 11. Interdisziplinäres Doktorandenseminar - GdCH Arbeitskreis Prozessanalytik CY - BAM Adlershof, Berlin, Germany DA - 12.03.2017 KW - Sample pretreatment KW - Conductive carbon tape KW - MALDI-TOF MS KW - PCA KW - Pollen PY - 2017 AN - OPUS4-39439 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Asadujjaman, Asad A1 - Kent, B. T1 - Temperature Sensitive Aggregation Behavior of Poly(Acrylamide-co-Acrylonitrile) in Water N2 - Thermoresponsive polymers have shown great potential in applications such as bioseparation, drug delivery and diagnostic. Only few thermoresponsive polymers that present an upper critical solution temperature (UCST), i.e. phase separate from solution upon cooling, in a relevant temperature range have been reported so far. Herein, a robust UCST-type copolymer of acrylamide (AAm) and acrylonitrile (AN) (poly(AAm-co-AN)) was prepared by reversible addition fragmentation chain transfer (RAFT) polymerization and its thermo-induced aggregation behavior in aqueous media was studied. We propose a model for the temperature-induced aggregation behaviour of UCST-type poly(AAm-co-AN) copolymer in aqueous solution on the basis of turbidity measurements, SLS, DLS, SANS and cryo-TEM. T2 - German Physical Society - Spring Meeting 2017 CY - Dresden, Germany DA - 19.03.2017 KW - Thermoresponsive polymers KW - UCST-type copolymer PY - 2017 AN - OPUS4-39465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Asadujjaman, Asad A1 - Ahmadi, Vahid A1 - Yalcin, M. A1 - ten Brummelhuis, N. T1 - Functional polymer based on 2,6-diaminopyridine with tunable UCST behaviour in water/alcohol mixture N2 - Thermoresponsive polymers are of great importance in numerous applications such as bioseparation, drug delivery, diagnostic and microfluidic applications. Only few thermoresponsive polymers that present an upper critical solution temperature (UCST), i.e. phase separate from solution upon cooling, in a relevant temperature range and green solvents such as water or ethanol have been reported. Indeed, polymers with UCST behavior below 60°C in alcohol or water/alcohol mixtures are extremely promising for the preparation of smart materials for sensing. In this work two novel functional polymers of based on a 2,6-diaminopyridine motif were synthesized by free radical polymerization. Their UCST-type transition temperature is tunable by varying either their concentration in solution or the type of solvent. Insights into this phenomenon will be given based on turbidimetry and temperature dependent dynamic light scattering T2 - German Physical Society - Spring Meeting 2017 CY - Dresden, Germany DA - 19.03.2017 KW - Thermoresponsive polymers KW - USCT-type polymers KW - Polymers based on 2,6-diaminopyridine PY - 2017 AN - OPUS4-39466 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Torge, Manfred A1 - Feldmann, Ines A1 - Tagle, R. T1 - SEM and Micro-XRF analysis to investigate stained glass windows N2 - Several restoration projects of stained-glass windows have been performed in Poland since 2010.Chemical analysis of glass samples was performed with SEM/EDX on a FEI ESEM-XL 30, (EDX-EDAX) and with Micro-XRF (M4 Tornado, Bruker).The chemical composition of medieval glass samples and of glass samples of the 19th Century have been determined. T2 - Technart2017 CY - Bilbao, Spain DA - 02.05.2017 KW - SEM KW - Micro-XRF KW - Glass composition PY - 2017 AN - OPUS4-40435 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marzok, Ulrich A1 - Müller, Ralf A1 - Reetz, R. A1 - Lauven, G. T1 - 3D High-temperature laser profilometry during sintering N2 - Most crucial for components of complex shape or heterogeneous micro structure, precise control of sintering has decisive influence on dimensional accuracy, mechanical integrity and reliability of sintered components. In these cases, only in situ 3D high-temperature shape screening during shrinkage would allow revealing temporary sinter warpage and hereby caused potential defects. Against this background, nokra Optische Prüftechnik und Automation GmbH, HTM Reetz GmbH and BAM developed a testing device for in situ 3D shape screening for ceramic and glass-ceramic tapes up to 1000°C by means of high-temperature laser profilometry. The local repeatability of the sample-sensor distance (sample height profile) is 10 µm at 1000°C. Current work is focused on dropping these restrictions in sample shape and temperature. In a second testing device, currently being in development, samples up to 5 cm x 5 cm x 5 cm can be measured at temperatures up to 1500°C.The presentation illustrates the current state of this work and possible applications of the method. T2 - 92. DKG Jahrestagung CY - Berlin, Germany DA - 19. 03. 2017 KW - Laser profilometry KW - 3D High-temperatue shape screening KW - Sintering PY - 2017 AN - OPUS4-40449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cruz Alonso, M. A1 - Fernandez, B. A1 - Alvarez, L. A1 - Gonzalez Iglesias, H. A1 - Traub, Heike A1 - Jakubowski, Norbert A1 - Pereiro, R. T1 - Bioimaging of metallothioneins in ocular tissue sections by LA-ICP-MS using bioconjugated gold nanoclusters N2 - Oxidative stress is produced by an imbalance between free radical production and biological system's ability to detoxify the reactive intermediates and repair the resulting damage. In the human eye the main causes of oxidative stress are the daily exposure to sunlight, chemical insults and the special microenvironment with abundant photo-sensitizers. For this reason, oxidative stress has been associated several ocular diseases, like aged-related macular degeneration (AMD). On the other hand, Metallothioneins (MTs) are a family of low molecular weight (6–7 kDa), cysteine-rich (30%) and metal-binding proteins. The cysteine residues can bind metal atoms such as zinc, copper, and cadmium via thiolate bonds. These proteins have a wide range of functions including defense against oxidative damage, intracellular storage and transport and metabolism of metal ions. The antioxidant properties of MTs reside in their capacity to capture and neutralize free radicals by binding and transferring zinc ions in a redox-dependent fashion, forming the antioxidant system Zinc-Metalothionein (Zn-MT). Highly sensitive analytical tools are required to study the relationship between Zn and MTs in sections from ocular tissues. These methodologies should permit the simultaneous localization (bioimaging) of metals and proteins. Laser ablation (LA) coupled to ICP-MS has shown a huge potential for bioimaging studies in biological tissues. In addition, the use of metal nanoclusters (NCs) as elemental tags will provide signal amplification, compared with other tags traditionally employed (e.g. polymeric tags). To this end, antibodies with gold nanoclusters (AuNCs) will be used in combination with LA-ICP-MS for the detection of different metallothioneins (MT 1/2 and 3) directly into the ocular tissue sections. - Methods: The AuNCs synthesized were bioconjugated with an Anti-MT 1/2 antibody and with Anti-MT 3 antibody. Next, using ocular tissue sections (5 microns thick) from different donors the immunoassays were performed. After the immunoassay protocol, imaging studies were carried out by LA-ICP-MS as well as by fluorescence (confocal microscope) in order to compare both methodologies. - Results: The MTs (measuring the Au signal) and the coordinated metals distribution (Zn and Cu) were successfully carried out in human ocular tissues, including sclera, choroid, retina and retinal pigment epithelium regions. The image patterns found in ocular tissues were in agreement with those reported by conventional immunohistochemistry. - Conclusions: It is possible to know the distribution of MT proteins and different coordinated metals using bioconjugated AuNCs and LA-ICP-MS. Proposed analytical tools could help to better understand the roles of the antioxidant system Zinc-Metalothionein in the eye. T2 - European Winter Conference on Plasma Spectrochemistry EWCPS-2017 CY - St. Anton, Austria DA - 19.02.2017 KW - Bioimaging KW - LA-ICP-MS KW - Nanocluster PY - 2017 AN - OPUS4-39293 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krause, B. A1 - Sieg, H. A1 - Kästner, Claudia A1 - Meyer, T. A1 - Reichardt, P. A1 - Lichtenstein, D. A1 - Burel, A. A1 - Boehmert, L. A1 - Jungnickel, H. A1 - Tentschert, J. A1 - Laux, P. A1 - Braeuning, A. A1 - Estrela-Lopis, I. A1 - Gauffre, F. A1 - Fessard, V. A1 - Thuenemann, Andreas A1 - Lampen, A. A1 - Luch, A. T1 - Detection of aluminum nanoparticles in biological media and in vitro N2 - Aluminum is the third most abundant element in the earth crust and therefore ubiquitously detectable in the environment. Mostly found in the form of derivatives such as silicates or oxides, it also occurs as metallic aluminum for example as colorant in sweets or in aluminum foil. With regard to potential toxicological effects, the different solubility of metallic aluminum nanoparticles compared to Al2O3 is of high relevance. Formation of ions may facilitate the crossing of blood-tissue barriers. Distribution towards other organs and subsequent re-formation of particulate aluminum due to milieu changes might occur. Therefore, the determination of solubility is required for proper risk assessment. Inductively coupled plasma mass spectrometry (ICP-MS) allows determination of aluminum with a detection limit of about 6 ppb. It could be proven that dissolution and solubility of metallic aluminum is significantly different when compared to Al2O3. Using ICP-MS in the single particle mode, a significant change in the behavior of both aluminum species was detected after undergoing the artificial digestion. Nearly unchanged in the saliva, particles show dissolution and high agglomeration during the gastric state before deagglomerating again in the intestine. Further analysis by time-of-flight secondary ion mass spectrometry (ToF-SIMS) revealed the uptake of both aluminum forms by proliferating and differentiated Caco-2 cells. For both particle forms different ions could be detected. Several aluminum-amino acid complex-derived ions from serine and valine were identified. In the case of Al2O3, Al2O2+, AlOH+, AlH2O+ and Al[(H2O)6]3+ were the main ions found co-localizing within treated cells. T2 - European Winter Conference for Plasma Spectrochemistry 2017 CY - Sankt Anton, Austria DA - 19.02.2017 KW - Aluminum KW - SP-ICP-MS KW - SAXS KW - Artificial digestion KW - Cellular uptake PY - 2017 AN - OPUS4-39201 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bierstedt, Andreas A1 - Riedel, Jens T1 - Improving the performance of the laser-spark ion source for the detection of volatile organic compounds under ambient conditions N2 - Recently, a novel ionization scheme for ambient MS has been introduced. It is based on a quasi-continuous laser induced plasma (LIP), ignited in front of the MS inlet. This setup comprises the advantages of an ambient probe, electro neutrality, a sufficient duty cycle, a ubiquitous plasma medium, low power consumption, the absence of solvents and high sensitivity. To assess its future applicability for the detection of volatile organic compounds, plasma properties and operating conditions are investigated to understand the processes, that lead to the unexpected formation of intact molecular ions. Comprehensive studies include optical Emission spectroscopy, shadowgraphic shockwave visualization and time-of-flight mass spectrometry. T2 - 50. Jahrestagung der Deutschen Gesellschaft für Massenspektrometrie CY - Kiel, Germany DA - 05.03.2017 KW - Laser-spark KW - Laser induced plasma KW - Mass spectrometry KW - Ambient ionization PY - 2017 AN - OPUS4-39309 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Torge, Manfred A1 - Feldmann, Ines A1 - Knabe, Nicole A1 - Toepel, J. T1 - Organic surface coatings on medieval stained glass and microbiological investigation N2 - Mediaeval stained glass has been treated with Polymethylmetacrylate coatings by Kwiatkowski in Poland during the 1950th. Such treated panels were found in the Johannis Church of Toruń (without protective glazing), in the Cathedral of Włocławek (behind a protective glazing), and on glass kept in exhibition cases in the museum of Toruń. Surface coatings have been detected and analyzed. There was no extensive contamination by fungi or bacteria if the glass was either coated or not. T2 - Glass Science in Art and Conservation 2017 CY - Lisbon, Portugal DA - 06.06.2017 KW - Microbiological investigation KW - Medieval stained glass KW - SEM analysis PY - 2017 AN - OPUS4-40573 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst T1 - Bridge Monitoring by Passive Seismic Data, First tests at the BLEIB reference structure N2 - Seismic wave velocities are related to elastic moduli and other properties and can serve as indicators for changes in the material. They are conventionally determined by active measurements. Using ideas from seismic interferometry Determination from stacked cross-correlations of registrations of man- made and natural noise (“passive seimics“) is an effective alternative, as these data might be available from vibration monitoring anyway. The validity of this approach is demonstrated by a simple experiment based on recordings of man made noise using accelerometers at the reference structure. The s-wave (or more probable. guided wave) velocity was determined to be 2100 m/s in both active and passive experiments. T2 - Passive Imaging and monitoring in wave physics: from seismology to ultrasound CY - Cargese, France DA - 05.06.2017 KW - Passive Seismics KW - Bridge monitoring KW - Elastic wave velocity PY - 2017 AN - OPUS4-40575 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Hüllmann, Dino A1 - Lilienthal, A.J. A1 - Kluge, Martin T1 - Bringing Mobile Robot Olfaction to the Next Dimension – UAV-based Remote Sensing of Gas Clouds and Source Localization N2 - This presentation introduces a novel robotic platform for aerial remote gas sensing. Spectroscopic measurement methods for remote sensing of selected gases lend themselves for use on mini-copters, which offer a number of advantages for inspection and surveillance. No direct contact with the target gas is needed and thus the influence of the aerial platform on the measured gas plume can be kept to a minimum. This allows to overcome one of the major issues with gas-sensitive mini-copters. On the other hand, remote gas sensors, most prominently Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensors have been too bulky given the payload and energy restrictions of mini-copters. Here, we introduce and present the Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS), which combines a novel lightweight TDLAS sensor with a 3-axis aerial stabilization gimbal for aiming on a versatile hexacopter. The proposed system can be deployed in scenarios that cannot be addressed by currently available robots and thus constitutes a significant step forward for the field of Mobile Robot Olfaction (MRO). It enables tomographic reconstruction of gas plumes and a localization of gas sources. We also present first results showing the gas sensing and aiming capabilities under realistic conditions. T2 - IEEE International Conference on Robotics and Automation (ICRA) CY - Singapore DA - 29.05.2017 KW - Tunable Diode Laser Absorption Spectroscopy (TDLAS) KW - 3-axis gimbal KW - Mobile Robot Olfaction KW - Tomographic reconstruction of gas plumes KW - Localization of gas sources KW - Aerial platform PY - 2017 AN - OPUS4-40547 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bennetts, V.H. A1 - Neumann, Patrick P. A1 - Kucner, T.P. A1 - Schaffernicht, E. A1 - Fan, H. A1 - Lilienthal, A.J. T1 - Probabilistic air flow modelling using turbulent and laminar characteristics for ground and aerial robots N2 - For mobile robots that operate in complex, uncontrolled environments, estimating air flow models can be of great importance. Aerial robots use air flow models to plan optimal navigation paths and to avoid turbulence-ridden areas. Search and rescue platforms use air flow models to infer the location of gas leaks. Environmental monitoring robots enrich pollution distribution maps by integrating the information conveyed by an air flow model. In this paper, we present an air flow modelling algorithm that uses wind data collected at a sparse number of locations to estimate joint probability distributions over wind speed and direction at given query locations. The algorithm uses a novel extrapolation approach that models the air flow as a linear combination of laminar and turbulent components. We evaluated the prediction capabilities of our algorithm with data collected with an aerial robot during several exploration runs. The results show that our algorithm has a high degree of stability with respect to parameter selection while outperforming conventional extrapolation approaches. In addition, we applied our proposed approach in an industrial application, where the characterization of a ventilation system is supported by a ground mobile robot. We compared multiple air flow maps recorded over several months by estimating stability maps using the Kullback-Leibler divergence between the distributions. The results show that, despite local differences, similar air flow patterns prevail over time. Moreover, we corroborated the validity of our results with knowledge from human experts. T2 - IEEE International Conference on Robotics and Automation (ICRA) CY - Singapore DA - 29.05.2017 KW - Mapping KW - Field robots KW - Environment monitoring and management KW - Aerial systems KW - Perception and autonomy PY - 2017 AN - OPUS4-40549 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Asadujjaman, Asad A1 - Wagner, Sabine A1 - Rurack, Knut A1 - Bertin, Annabelle T1 - Temperature switches “on” and “off” nanoparticle fluorescence in a core/shell/shell architecture N2 - Fluorescent nanoparticles that light “on/off” by applying external stimuli are of particular interest in the fields of sensing, diagnostics, photonics, protective coatings and microfluidics. The current challenge for these materials is for instance to combine fluorescence and its response to a stimulus such as temperature in a precise manner. Here we present such a system based on a core/shell/shell architecture consisting of a silica core with a fluorescent layer and a thermoresponsive shell. In this work the silica core nanoparticles were first coated with a fluorescent shell using surface initiated reversible addition-fragmentation chain transfer (RAFT) polymerization. The fluorescent nanoparticles were then completely engulfed by a switchable protective coating made of thermoresponsive poly(N-isopropylacrylamide). The fluorescence of the nanoparticles could be “switched on” at room temperature and “switched off” with increasing environmental temperature because of the presence of the thermoresponsive layer. Insights into this phenomenon will be given based on temperature dependent fluorescence measurements and dynamic light scattering. T2 - Makromolecular Konferenz CY - Freiburg, Germany DA - 15.02.2017 KW - Thermoresponsive polymers KW - Sensors KW - Core/Shell/Shell PY - 2017 AN - OPUS4-39230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kage, Daniel A1 - Hoffmann, Katrin A1 - Witkamp, M. A1 - Ameskamp, J. A1 - Göhde, W. A1 - Thiele, T. A1 - Schedler, U. A1 - Resch-Genger, Ute T1 - Time domain flow cytometry utilizing lifetime-encoded polymer microparticles N2 - Flow cytometry is a widely used method in biological research and medical diagnostics. Depending on the respective application, two opposing directions of development are currently of interest. On the one hand, there is a need for analyses of growing complexity employing more and more fluorescent labels and codes. On the other hand, cost-effective methods and portable, miniaturized, and robust instruments are desired. Commonly performed spectral multiplexing utilizing a color code suffers from several problems, such as the sensitivity of fluorescence intensity measurements to fluctuations in excitation light intensity and dye concentration and hence, photobleaching, dye leaking for certain encoding procedures, and spectral crosstalk, limiting the achievable number of detection channels. Moreover, it typically requires several costly excitation light sources. An innovative alternative can be lifetime multiplexing and the discrimination between different encoding fluorophores and carrier beads based on their fluorescence decay kinetics. In order to examine the potential of this approach, dye encoded beads (lifetime encoded surface chemistry) were prepared using several fluorophores from different dye classes and their suitability for lifetime discrimination in a flow was tested in conjunction with a custom designed flow cytometer equipped with a pulsed light source and a fast detector. In a first step, the spectroscopic properties of micrometer-sized dye-stained PMMA beads were studied by means of steady state and time-resolved photoluminescence measurements. For the performance of studies on the practical use of these microbeads in flow cytometry applications, a custom-built demonstrator model for a flow system was employed. Our results demonstrated that lifetime discrimination and simultaneous readout of a ligand fluorescence signal for analyte quantification with a set of dye-stained polymer microbeads at single wavelength excitation is feasible. These studies are expected to pave the road for new applications of fluorescence lifetime multiplexing within the framework of time-domain flow cytometry and bead-based assays. T2 - ANAKON 2017 CY - Tübingen, Germany DA - 03.04.2017 KW - Flow cytometry KW - Fluorescence KW - Life sciences KW - Lifetime encoding KW - Polymer particles PY - 2017 AN - OPUS4-39995 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radunz, Sebastian A1 - Tschiche, Harald Rune A1 - Moldenhauer, Daniel A1 - Resch-Genger, Ute T1 - Simple approach to pKa tunable BOIDPY-based fluorescent pH sensors N2 - Successfull synthesis of pH-responsive fluorescence ON/OFF sensor dyes with tunable pK values covering the pH range of 5 to 12 Immobilizing of multiple dyes with different pK values into a polymer host matrix provides a pH sensor with a dynamic range. T2 - First European/ 10th German BioSensor Symposium CY - Potsdam, Germany DA - 20.03.2017 KW - Fluorescence KW - Sensing KW - pH PY - 2017 AN - OPUS4-39683 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Keller, Julia A1 - Lörchner, Dominique A1 - Riedel, Juliane A1 - Rasenko, Tatjana A1 - Köppen, Robert A1 - Koch, Matthias T1 - Development of analytical method and certified reference material for zearalenone in edible oils N2 - Quality and safety of food products require their reliable analysis. Contaminants, in particular mycotoxins, are key-components for food safety. About 25 % of the world's food crops are contaminated with mycotoxins posing a severe health risk to humans. In order to strengthen food safety and consumer protection the European Commission (EC) set maximum levels for priority mycotoxins in certain foods for human consumption. In 2013, the EC and CEN (European Committee for Standardization) started an initiative to standardize analytical methods for mycotoxins in food which gained increasing relevance, e.g. zearalenone (ZEN).[1] ZEN, an estrogenic mycotoxin produced by several Fusarium species, contaminates cereal crops worldwide. Due to its lipophilic nature ZEN is often found in edible oils (particularly in maize germ oils) derived from contaminated plants. Therefore, an European maximum level of 400 µg/kg is currently in force.[2] To perform reliable food analysis a sustainable metrological infrastructure is of major importance enabling the quantification of priority mycotoxins (here: ZEN). To achieve this goal an integrated approach is needed targeted at the development of validated analytical methods and certified reference materials (CRM). A highly selective method for ZEN in edible oils will be presented, based on solid phase extraction (SPE) using hydrazine-functionalized particles. This method was developed for manual application using commercial SPE cartridges as well as for automated SPE-HPLC online coupling. While ZEN is covalently coupled to the solid phase by means of a hydrazone bond, undesired matrix components can be removed very efficiently. Finally, ZEN is decoupled from the solid phase, leading to highly purified extracts which are measured by HPLC-FLD. The development of the first European Reference Material (ERM®) for ZEN in maize germ oil (ERM®-BC715) will be presented and discussed. This ERM®-project underpins the urgent need for mycotoxin-CRMs to support food safety and public health. [1] European Commission (EC) Mandate M/520 (2013) for standardisation addressed to CEN for methods of analysis for mycotoxins in food. [2] Commission Regulation (EC) No 1126/2007 amending Regulation (EC) No 1881/2006 setting maximum levels for certain contaminants in foodstuffs as regards Fusarium toxins in maize and maize products. T2 - Anakon CY - Tübingen, Germany DA - 03.04.2017 KW - Mycotoxins KW - Food safety KW - Analytical method KW - Reference material PY - 2017 AN - OPUS4-39860 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Esteban-Fernandez, Diego A1 - Traub, Heike A1 - Hutchinson, R. A1 - Jakubowski, Norbert A1 - Wilkins, J. A1 - Summerfield, L. A1 - McLachlin, K. T1 - High resolution laser ablation NWRimage system for single cell imaging N2 - The traceability and availability of nanoparticles enables their use to enhance a variety of nano-biological and nano-medicinal applications. The particular size and shape of nanoparticles determine the uptake rate and pathway into the cell, and therefore impact specific cell components and processes. Selecting specific particle types allows researchers to target the process or structure of interest, with minimal additional impact. This can be used for drug or DNA delivery, and is being explored for use in oncology. Understanding the different uptake mechanisms and impacted processes requires sub-cellular Imaging resolution to determine, for example, whether or not the nanoparticles are reaching the nucleus. Sub-cellular imaging has traditionally been challenging to achieve with laser ablation ICP-MS due to a lack of sensitivity at small spots. Bioimaging using LA-ICP-MS is a well-established technique, but usually applied on the tissue scale, which depends on larger spot areas where sensitivity is less problematic. The improved sensitivity and washout from the NWRimage has allowed faster imaging of smaller spots. The NWRimage also provides the possibility of true sub-micron spot sizes. This work compares the capabilities of standard laser Ablation (NWR213 system) with results from the NWRimage platform, which has been optimized for imaging applications. T2 - European Winter Conference on Plasma Spectrochemistry CY - St. Anton, Austria DA - 19.02.2017 KW - Laser ablation KW - Imaging KW - Nanoparticle PY - 2017 AN - OPUS4-39281 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kok, H. T. A1 - Donskyi, Ievgen A1 - Adeli, M. A1 - Unger, Wolfgang A1 - Haag, R. T1 - 2D nanomaterials with switchable pathogen binding N2 - Graphene and its derivatives have recently attracted much attention for sensing and deactivating pathogens. However, mechanism of multivalent interactions at the graphene-pathogen interface are not fully understood. Since different physicochemical parameters of graphene play a role at this interface, control over graphene’s structure is necessary to study the mechanism of these interactions. In this work, zwitterionic graphene nanomaterials (ZGNMs) were synthesized with defined isoelectric points and exposure, in terms of polymer coverage and functionality. Then, the switchable interactions of ZGNMs with E. coli were investigated to study the validity of the generally proposed “trapping” mechanism for inactivating pathogens by functionalized graphene derivatives. The ZGNMs were able to controllably trap and release E. coli by crossing their isoelectric points. T2 - 4th Erlangen Symposium on Synthetic Carbon Allortopes 2017 CY - Erlangen, Germany DA - 25.09.2017 KW - Graphene KW - XPS KW - NEXAFS KW - Zwitterionic graphene nanomaterials PY - 2017 AN - OPUS4-47084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Donskyi, Ievgen A1 - Azab, W. A1 - Bergmann, T. A1 - Osterrieder, K. A1 - Adeli, M. A1 - Abad, K. A1 - Unger, Wolfgang A1 - Haag, R. T1 - Inhibition of Herpes Virus by Specific and Non-specific Interactions With Graphene Conjugates N2 - Herpes viruses (HSV) are global, host-adapted pathogens that cause a widespread diversity of diseases. The frequency of HSV infections all over the world has amplified over the last years, making it a major concern in the area of public health. Therefore, synthesis of systems that can inhibit development of these viruses is required. Various compounds already have shown inhibition of HSV, but concentration of these inhibitors is relatively high and resistance against those drugs is challenging. Combination of biological knowledge, about structure of the active site on the surface of HSV that is responsible for inhibition of the pathogen, with the chemistry of graphene results in 2D systems with the ability of specific and nonspecific interactions with HSV. In this work, 2D nanomaterials with picomolar IC50 against HSV are synthesized by conjugation of peptides to the surface of graphene. 2D nanomaterials are characterized by various methods, including XPS, AFM and IR. Biological evaluation showed high potency of synthesized nanomaterials to inhibit HSV and therefore underlined possibility to use such materials in future biomedical applications. T2 - Jubiläumskongress 150 Jahre GDCh Wissenschaftforum Chemie CY - Berlin, Germany DA - 12.09.2017 KW - Graphene KW - Graphene 2D nanomaterial KW - XPS KW - Inhibition of HSV virus PY - 2017 AN - OPUS4-47085 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kastanias, Elaine A1 - Özcan Sandikcioglu, Özlem T1 - Chemical interaction mechanisms of metal reducing bacteria on gold surfaces N2 - Bacterial biofilms represent a ubiquitous form of microbial life on Earth. Due to an evolved armory of protean biological responses to external stimuli, bacteria are able to adhere to, colonize and thrive on virtually all surfaces, whether natural or synthetic, even in challenging environmental conditions. In addition to significant health risks, biofilms are among the salient contributors to the deterioration of metals and their alloys, thereby causing safety risks for technical equipment. Hence, understanding the interaction mechanisms of electroactive sessile bacteria with metal surfaces is vital for facilitating the development of efficient control strategies and novel anti-fouling surfaces in various industries and technologies. The present study focusses on a combined spectroelectrochemical approach, melding methods of surface enhanced Raman spectroscopy (SERS) and electrochemical techniques, to investigate the chemical characteristics and redox activities of electroactive bacteria during the initial stages of biofilm formation. Gold has been selected as a model substrate due to its inert character, considerably high surface enhancement factor, as well as its capability to allow surface chemistry modifications and substrate polarization in order to precisely control the surface charge. Square wave voltammetry (SWV) and cyclic voltammetry (CV) studies have been performed for quantitative determination of flavin concentration and electrochemical impedance spectroscopy (EIS) has been utilized to study the changes in electrochemical processes within biofilms during different stages of growth. Shewanella sp. have been chosen as microorganisms within this work due to their versatile exoelectrogenic respiratory behavior and their distinct ability to reduce metals via extracellular electron transfer mechanisms involving self-secreted electron shuttle redox molecules such as flavins. To further explicate the process of diffusion of flavins within biofilms, a model system has been developed to simulate the structural features of the bacterial extracellular polymeric substances typically found in biofilms. This has been achieved by creating hydrogel films comprised of calcium-cross-linked alginate. The results demonstrate an interplay of factors contributing to the initial phases of bacterial settlement and biofilm formation as a function of environmental parameters. Furthermore, the results allow insight into the diffusion of flavins, much like they would in a natural biofilm, and how their redox behavior affects the biofilm development. T2 - 232nd ECS Meeting CY - National Harbor, MD, USA DA - 01.10.2017 KW - Biofilms KW - Electrochemistry KW - Microbiology KW - Bacterial Extracellular Electron Transfer Mechanisms KW - Surface Enhanced Raman Spectroscopy KW - Spectroelectrochemical Techniques KW - Biocorrosion PY - 2017 AN - OPUS4-47248 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steger, Simon A1 - Rabin, Ira A1 - Stege, H. A1 - Hahn, Oliver T1 - Non-invasive, spectroscopic study of a modern reverse glass painting N2 - We present the first spectroscopic study on a reverse glass painting form the classic modern period (1905-1955). Marianne Uhlenhuth’s painting “Ohne Titel, 1954” shows characteristics like experimental use of colorants and abstract compositions, which are well-established in classic modern art. Compared to stained glass, reverse glass paintings are viewed in reflected light, hence they reveal strong and intense colors. New inorganic pigments, development of synthetic organic pigments and the simultaneous supersession of well-known ancient colorants result in experimental works and remarkable pigment mixtures in this period of time. An in-situ, non-invasive approach was used to study the pigments and binding media. In-situ measurements were carried out using Raman spectroscopy (i-Raman®Plus, Bwtek Inc., 785 nm, 20× objective, resolution 4 cm-1), X-ray fluorescence (Tracer III-SD, Bruker AXS Microanalysis GmbH, 40 kV, 15 μA), VIS spectroscopy (SPM 100, Gretag-Imaging AG) and DRIFTS: Diffuse Reflection-Infrared-Fourier-Transform Spectroscopy (ExoScan, Agilent GmbH, 4000-650 cm-1, 256 scans, resolution 4cm-1). The pigments consist of inorganic as well as organic materials. Phthalocyanin green (PG7, colour index No. 74260), viridian and emerald green were used for the green areas. The yellow parts consist of chrome yellow and cadmium yellow. Pigment Yellow 1 (C.I. 11680) was used for the dark yellow/orange part. Red areas were characterized by the presence of cadmium and selenium (cadmium red) in the XRF spectrum. Ultramarine was detected in the blue parts. Concerning the violet color PR81 (bluish red, C.I. 45160:1) in mixture with PG7 (bluish green) were identified as main components. We want to outline that PR81 was rarely found in paintings. It was only recorded in the palettes of Lucio Fontana and Mary Cassatt before. The dark violet areas consist of Prussian blue and an unknown red (organic) colorant. Brown iron oxide was identified as the brown pigment. Bone black in mixture with black iron oxide were used as black materials and zinc white and titanium white as white pigments. XRF analysis of the metal color yields intense copper, zinc and nickel peaks (intensity ratio 3:3:1), which corresponds to “new silver” alloy. Barite and chalk are the fillers in this painting. Results of DRIFTS spectra show gum sometimes mixed with protein or oil (metal soaps) as binding media. The results point out that reverse glass paintings from the classic modern period are excellent examples to study the evolution of new pigments and their acceptance in artist’s palettes. T2 - CSI-XL CY - Pisa, Italy DA - 11.06.2017 KW - Pigments KW - Reverse glass painting KW - Spectroscopy PY - 2017 AN - OPUS4-42336 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Moufid, M. A1 - Tiebe, Carlo A1 - El Bari, N. A1 - Hübert, Thomas A1 - Bouchikhi, B. T1 - An electronic nose for the detection and discrimination of environmental pollutant gases in the aglomeration of the city of meknes N2 - The ambient air quality around residential areas is influenced by industrial objects, including industrial sewage, livestock farming and landfill sites. These sites are generating malodours or toxic gases involving degradation of ambient air quality, which may constitute a risk in human health if maximum emission limits are exceeded. Therefore, appropriate tools allowing detection of harmful or bad odorous, subsequently contributing to a reduction of odour nuisance are greatly needed. The aim of this study was to demonstrate the capability of an electronic nose E-nose to discriminate various gas samples collected from six different sites from the agglomeration of Meknès city corresponding to municipal landfill, in the city at 2 km of landfill, industrial estate wastewater, traffic road, and sheep breeding. The investigations were carried out with an E-nose system based on an array of six-commercial MQ sensors. Further, a pattern recognition technique known as Principal Component Analysis (PCA), Linear Discriminent Analysis (LDA), and Support Vector Machines (SVMs) was implemented to study the discrimination capability of the sensor array. PCA results demonstrate excellent discriminating ability of the dataset with a score of 99.47 %. Additionally, another measurement database containing 12 air atmospheric samples was projected on the previously built PCA model to check the stability of the E-nose. The LDA was applied to the same dataset and showed a good discrimination between the ambient air samples of the six sites. Furthermore, SVMs technique was also used to build a classifier and reached a score of 100 % success rate in the recognition of the analysed samples. The obtained results of six areas demonstrate the increasing interests and the applicability of E-noses for ambient air quality classification of six areas caused by emitted decomposed organic matters. T2 - Eighth International Workshop on Biosensors for Food Safety and Environmental Monitoring CY - Rabat, Morocco DA - 12.10.2017 KW - Pattern recognition methods KW - Electronic nose KW - Gas sensor KW - Malodour detection KW - Environmental analysis PY - 2017 AN - OPUS4-42525 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni A1 - Kupsch, Andreas A1 - Mueller, Bernd R. A1 - Lange, Axel T1 - X-ray refraction 2D and 3D techniques N2 - X-ray refraction techniques represent a very promising, yet not so wide-spread, set of X-ray techniques based on refraction effects. They allow determining internal specific surface (surface per unit volume) in a non-destructive fashion, position and orientation sensitive, and with nanometric detectability. While they are limited by the X-ray absorption of the material under investigation, we demonstrate showcases of ceramics and composite materials, where understanding of microstructural features could be achieved in a way unrivalled even by high-resolution techniques such as electron microscopy or computed tomography. T2 - ICTMS 2017 CY - Lund, Sweden DA - 26.06.2017 KW - X-ray refraction KW - Composites KW - Damage KW - Cracks KW - Cearmics PY - 2017 AN - OPUS4-41042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Akhmetova, Irina A1 - Wilke, Manuel A1 - Emmerling, Franziska T1 - In situ investigation of mechanochemical syntheses of manganese phosphonates N2 - The exploration of metal phosphonates chemistry has gained great interest during the last decades, because of their structural diversity. Transition metal phosphonates are promising candidates for an application as electrocatalysts in oxygen reduction reactions (ORR). Here, we present the in situ investigation of mechanochemical syntheses of two different manganese phosphonates by synchrotron X-ray diffraction. Nitrilotri(methylenephosphonic acid) and N,N-Bis(phosphonomethyl)glycine were chosen as ligands. The liquid-assisted milling process can be divided into three steps, including an amorphous stage. One of the products has not been obtained by classical solution chemistry before. These metal phosphonates and/or their derivatives are considered to be active in electrochemical energy conversion. The verification of their applicability is one of the topics of our resent research. T2 - 9th International Conference on Mechanochemistry and Mechanical Alloying CY - Kosice, Slovakia DA - 03.09.2017 KW - Mechanochemistry KW - In situ KW - Metal phosphonate KW - XRD PY - 2017 AN - OPUS4-41920 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hoffmann, Katrin A1 - Pauli, Jutta A1 - Resch-Genger, Ute T1 - New NIR fluorescence reference materials and quantum yield standards for standardization of fluorescence-based measurements N2 - Luminescence techniques are amongst the most commonly used analytical methods in the life and the material sciences due to their sensitivity and nondestructive character. All photoluminescence signals are, however, affected by wavelength-, polarization- and time-dependent instrument-related effects. Furthermore, substantial challenges to measure absolute luminescence intensities complicate the comparison of data recorded with different instruments and on the same instrument at different times. These problems can be easily resolved with fluorescence standards used for instrument performance validation (IPV) and determination of instrument-to-instrument variations, which allow to measure, quantify, and monitor the wavelength-dependent spectral responsivity for typically used instrument settings. For example, a set of liquid fluorescence standards, the BAM Kit F001-F005, and a ready-to-use glass-based fluorescence standard BAM F-012 developed and certified by BAM enable the characterization of many fluorescence parameters in the UV/vis wavelength range. For the increasingly used near infrared (NIR) region, standards and calibration tools are still very rare. Reliable spectral fluorescence standards and intensity or quantum yield standards are currently not available for the NIR, even though in biology, molecular imaging, and clinical diagnostics fluorescence labels absorbing and emitting in the long wavelength region beyond 650 nm are being increasingly used. This limitation hampers the reliability and comparability of fluorescence measurements in the NIR and calls for simple fluorescence standards for instrument characterization and for the quantification of fluorescence intensities and efficiencies to improve the comparability of the emission measurements in the NIR. This encouraged us to assess the potential of several NIR-emitting materials as spectral fluorescence standards, thereby extending the BAM Kit from the UV/vis into the NIR up to 950 nm. Moreover, we currently certify quantum yield standards for the UV/vis/NIR to improve the reliability of relative measurements of this spectroscopic key quantity particularly > 650 nm. These tools enable an instrument characterization, signal referencing, quality assurance, traceability, and method validation now also for wavelengths > 650 nm, thereby improving the reliability of fluorescence data in pharmaceutical research, medical and clinical diagnostics, material analysis, and environmental monitoring. T2 - 15th Conference on Methods and Applications in Fluorescence (MAF) CY - Brugge, Belgium DA - 10.09.2017 KW - Fluorescence reference materials KW - Quantum yield standard KW - Glass-based fluorescence standard PY - 2017 AN - OPUS4-41990 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jankevics Jones, H. A1 - Sarma, Dominik A1 - Rurack, Knut A1 - Latunde-Dada, S. A1 - Bott, R. T1 - Determination of core-shell particle mass and size distribution, density, and distinguishing shell thicknesses by resonant mass measurements N2 - An important aspect of micro or nano particles development is the understanding and control of the particle structure, as it can be determining for particle’s final function, and it affects among other things potential further surface functionalisation/modification. This work shows the capability of resonant mass measurements (RMM) to measure the mass and density of micron sized particles. The technology utilizes a suspended MEMS microchannel resonator, through which individual particles transit across the resonator altering the resonant frequency, which is then detected using an optical-based method. Changes in frequency observed when a particle enters the microchannel resonator are proportional to the buoyant mass of the particle, and can be translated into mass, size or surface area. RMM therefore allows particle concentration to be determined as well as particle mass in a single measurement. Furthermore, a method for estimating the density distribution of particles from RMM measurements has been developed. This uses the convolution of the buoyant mass distribution of the particles obtained when suspended in different fluids. By combining the data from the density and mass determinations, small mass shifts arising from applying a coating to a particle can be estimated, and the resulting shell thicknesses calculated. These methods have been applied to silica coated and uncoated polystyrene latex particles. RMM shows that it can be used to measure, and distinguish between, silica shell thicknesses that are in the order of 10s of nanometres on hybrid micron-sized particles T2 - 7th International Colloids Conference CY - Sitges, Barcelona, Spain DA - 18.06.2017 KW - Core-shell particles KW - Resonant mass measurement PY - 2017 AN - OPUS4-42259 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jankevics Jones, H. A1 - Sarma, Dominik A1 - Rurack, Knut A1 - Latunde-Dada, S. A1 - Bott, R. T1 - Determination of core-shell particle mass and size distribution, density and distinguishing shell thickness by resonant mass measurements N2 - In micro or nano particles development it is important to understand and control the particle structure, as it affects among other things the potential further surface functionalisation/modification possible. This work shows the capability of resonant mass measurements (RMM) to measure the mass and density of micron sized particles. The technology utilizes a suspended MEMS microchannel resonator, through which individual particles transit across the resonator altering the resonant frequency, which is then detected using an optical-based method. Changes in frequency observed when a particle enters the microchannel resonator are proportional to the buoyant mass of the particle, and can be translated into mass, size or surface area. RMM therefore allows particle concentration to be determined as well as particle mass in a single measurement. Furthermore, a method for estimating the density distribution of particles from RMM measurements has been developed. This uses the convolution of the buoyant mass distribution of the particles obtained when suspended in different fluids. By combining the data from the density and mass determinations, small mass shifts arising from applying a coating to a particle can be estimated, and the resulting shell thicknesses calculated. These methods have been applied to silica coated and uncoated polystyrene latex particles. RMM shows that it can be used to measure, and distinguish between, silica shell thicknesses that are in the order of 10 to 55 nanometres on hybrid micron-sized particles. RMM can also determine the shell density. T2 - UK Colloids 2017 CY - Manchester, UK DA - 10.07.2017 KW - Core-shell particles KW - Resonant mass measurement PY - 2017 AN - OPUS4-42262 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bolz, Axel A1 - Rurack, Knut A1 - Buurman, Merwe T1 - Microfluidic Paper-Based Analytical Devices with Surface Enhanced Raman Scattering Detection N2 - Microfluidic paper-based analytical devices (μPADs) in combination with surface enhanced Raman scattering (SERS) provide a way for analyses of complex mixtures. The μPADs can be used for the chromatographic separation of different compounds of mixtures in combination with the separate detection of the analytes in different zones on the paper by SERS. SERS allows to observe analytes directly without labelling in low concentrations in aqueous solutions and to identify them by their spectral fingerprint. SERS substrates on the μPADs were created by drying standard silver nanoparticle (AgNP) solution on the paper. The microfluidic structure of the μPADs was prepared by wax printing. As a model system, an aqueous solution of the non-fluorescent analyte adenine and two fluorescent dyes tris(2,2’-bipyridyl)dichlororuthenium(II) and sulforhodamine B was tested. The dependency of the SERS signal intensity on the analyte concentration can be fitted using a Langmuir isotherm curve progression. With this approach, a semi-quantitative analysis of the components is possible. The reproducibility and stability of the measurement procedure was tested with several measurements over time, different NP batches, and with different analytes in different concentrations and resulted in an average relative standard deviation of 16 %. The SERS spectra of the mixture of the model system are dominated by one compound depending on the concentration ratio. For the detection and identification of all components of the mixture, the compounds were therefore separated on the μPADs and measured at different positions. The position of adenine on the μPADs is dependent on the AgNP coverage of the paper. Due to this effect, it possible to detect adenine on a defined point on the μPADs and to get an information on the concentration in a mixture of three components. T2 - 30. Tag der Chemie Humboldt-Universität zu Berlin CY - Berlin, Germany DA - 05.07.2017 KW - SERS KW - µPAD PY - 2017 AN - OPUS4-42265 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wilke, Olaf A1 - Horn, Wolfgang A1 - Mull, B. A1 - Richter, Matthias A1 - Brödner, Doris A1 - Mölders, N. A1 - Renner, M. T1 - Reproducibly emitting reference material for quality assurance/quality control of emission test chamber measurements N2 - Volatile Organic Compounds (VOC) are ubiquitous in the indoor air, since they emit from materials used indoors. Investigations of these materials are mostly carried out in test chambers under controlled climatic conditions. Quality control of these test chamber measurements is important but there is a lack of commercially available homogenous reference materials as required for round robin tests or quality assurance of laboratories. The approach of the present study is the impregnation of a supporting material with VOC, which are reproducibly released in measurable chamber air concentrations under standardised test conditions. A polymer made of Thermoplastic Polyurethane (TPU) was chosen as carrier material. It was impregnated with the VOC trimethyl pentanediol isobutyrat (texanol). T2 - Healthy Buildings 2017 Europe CY - Lublin, Poland DA - 02.07.2017 KW - Emissions testing KW - Volatile organic compounds KW - Polymeric material KW - CO2 assisted impregnation PY - 2017 AN - OPUS4-42351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steger, Simon A1 - Hahn, Oliver T1 - Study of modern reverse paintings on glass with Raman Spectroscopy N2 - The technique of painting on the reverse side of glass was rediscovered by artists in the 20th and gained especially in Germany strong popularity. Compared to other techniques (e.g. canvas, mural paintings), the paint layers are applied in reverse succession. The paintings are viewed in reflected light, thus revealing an impressive gloss, luminosity, and depth of color. Reverse glass paintings comprise a non-porous glass substrate and multi-layered paint system, hence delamination of the paint layer is the most common disfigurement. Scientific investigation of the material provides important information for appropriate conservation concepts. Transport of the precious and fragile objects to the lab is often not feasible. Therefore, in-situ, non-invasive analysis is necessary to analyze colorants and binders. Based on modern reverse glass paintings, we clarify advantages and limitations of mobile Raman spectroscopy for the identification of colorants. We compare the use of mobile Raman spectroscopy with other methods of our mobile lab (i.e. X-ray fluorescence (XRF), Diffuse Reflectance Fourier Transform Infrared Spectroscopy (DRIFTS). T2 - 9th International Congress on the Application of Raman Spectroscopy in Art and Archaeology (RAA2017) CY - Évora, Portugal DA - 24.10.2017 KW - Reverse glass painting KW - Raman spectroscopy KW - Synthetic organic pigments PY - 2017 AN - OPUS4-42825 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph A1 - Johann, Sergej A1 - Müller, Maximilian A1 - Bartholmai, Matthias T1 - Embedded passive RFID-based sensors for moisture monitoring in concrete N2 - Moisture measurements based on passive RFID based sensors. These sensors are embedded into stell reinforced concrete to enable long-term monitoring. T2 - IEEE Sensors 2017 CY - Glasgow, Scotland, UK DA - 30.10.2017 KW - Concrete KW - Embedded sensors KW - RFID based sensors KW - Passive sensors KW - Moisture monitoring PY - 2017 AN - OPUS4-42746 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lauer, Franziska A1 - Diehn, Sabrina A1 - Seifert, Stephan A1 - Weidner, Steffen A1 - Kneipp, Janina T1 - Quantitative profiling of pollen grain mixtures by multivariate MALDI-TOF MSI N2 - Anemophilous plants produce pollen grains, which have to be monitored to provide a national information network for persons suffering from an allergy. The current conventional characterization and identification of pollen is performed by time-consuming microscopic examinations based on the genus-specific pollen shape and size. These examinations need proficient researchers, are not statistically validated, and additionally rely on relatively inaccurate observations of the pollination process. A variety of spectroscopic and spectrometric approaches have been proposed to develop a fast and reliable pollen identification using specific molecular information. Amongst them, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was recently applied for the rapid investigation of such complex biological samples. The combination of obtained peak patterns from pollen mass spectra and multivariate statistic provide a powerful tool for identifying taxonomic relationships. A novel application based on the use of conductive carbon tape as MALDI target simplified the sample preparation and yielded enhanced the quality of the mass spectra. This led to a sufficient statistical analysis of the MS pattern, which is important when identify pollen grains in natural species mixtures. Based on this approach, promising results could be obtained by MALDI-TOF MS imaging (MSI) of artificial pollen mixtures followed by multivariate analysis. Of special interest is here the determination of the detection limit (number of pollen grains). Therefore, different pollen grain compositions were investigated for quantitative profiling of each individual pollen species within these complex mixtures. Our results can be used to improve the taxonomic differentiation and identification of pollen species and might be useful for the development of a routine method to identify pollen based on imaging mass spectrometry. T2 - Euroanalysis 2017 CY - Stockholm, Sweden DA - 28.08.2017 KW - MALDI-TOF MS KW - Imaging KW - Conductive carbon tape KW - Pollen KW - PCA PY - 2017 AN - OPUS4-42749 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lauer, Franziska A1 - Diehn, Sabrina A1 - Weidner, Steffen A1 - Kneipp, Janina T1 - Identification of pollen grains in mixtures using hyperspectral MALDI-TOF MS imaging N2 - Anemophilous plants produce pollen grains, which promote allergies. Therefore, pollen are monitored to provide a national information network. Their conventional identification and differentiation is performed by time-consuming microscopic examinations based on the genus-specific pollen morphology. A variety of spectroscopic and spectrometric approaches have been proposed to develop a fast and reliable pollen identification using specific molecular information. Amongst them, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) showed a high potential for the successful investigation of such complex biological samples. Specifically, it was illustrated that MALDI-MS imaging provides a powerful tool to identify pollen grains in pollen mixtures on the basis of ion intensity plots. More recently, the evaluation of the obtained peak patterns from pollen mass spectra with multivariate statistics enables a consistent and rapid identification of the taxonomic relationships. A novel application using conductive tape on the MALDI target simplifies sample preparation and enhanced the quality of the mass spectra. This led to a comprehensive analysis of the MS patterns, which is important when identifying pollen grains from different plant species in mixtures. Here, we present further developments in MALDI-MS imaging of mixtures of pollen from different plant species. By combining conductive tape sample preparation with MALDI MSI and chemometric analysis, first promising results were obtained. In addition, we discuss the ability of partial least square regression (PLS-R) to identify pollen species based on independent reference spectra and present first results obtained with artificial pollen mixtures. These methods will be used in future online identification of pollen species in natural pollen mixtures. T2 - Workshop “FT‐IR Spectroscopy in Microbiological and Medical Diagnostics” CY - Robert Koch‐Institute, Berlin, Germany DA - 19.10.2017 KW - MALDI-TOF MS KW - Imaging KW - Pollen KW - MVA PY - 2017 AN - OPUS4-42750 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hupatz, H. A1 - Schröder, H. A1 - Heinrich, Thomas A1 - Lippitz, Andreas A1 - Unger, Wolfgang A1 - Schalley, C. T1 - Deposition of redox-switchable rotaxanes on surfaces N2 - Deposition of Redox-switchable rotaxanes on surfaces Nature has created molecular machines which can perform a variety of different tasks. They exhibit defined operational pathways and order, resulting in directed macroscopic effects. Within the last decades researchers have been developing numerous artificial molecular machines which are so far mostly operating in solution. However, this represents a major obstacle for the generation of a macroscopic output, due to the random orientation of molecules in solution. As a general approach to this problem, interfaces have been used to generate ordered arrays of functional molecules. Recently, we developed a new class of redox-switchable crown ether/ammonium-based [2]- and [3]rotaxanes which incorporate redox-active tetrathiafulvalene and naphthalene diimide units in their wheels resulting in emergent optoelectronic properties. Electrochemical stimuli influence the interactions between the two macrocycles of [3]rotaxanes and induce conformational changes. In a proof-of-principle study [2]pseudorotaxanes were deposited on gold surfaces by “click”-reaction to azide-terminated self-assembled monolayers to generate ordered arrays of redox-active rotaxanes on-surface. X-ray photoelectron spectroscopy (XPS) confirms the successful deposition of a rotaxane monolayer, though angle-resolved near-edge X-ray absorption fine structure spectroscopy (NEXAFS) exhibits poor order of the rotaxanes. Following, new terpyridine-stoppered rotaxanes will be synthesised opening a pathway for the deposition of [2]- and [3]rotaxanes in a layer-by-layer metal-mediated self-assembly procedure. This approach would allow for a programmed sequence of different rotaxanes in multilayers. Electrochemical on-surface switching will be investigated by angle-resolved NEXAFS spectroscopy, XPS, cyclic voltammetry and UV/Vis spectroscopy. A more detailed understanding of the electron-transfer between the surface and the different rotaxane layers as well as of the on-surface switching could give rise to potential applications like optoelectric data-storage devices or potential-driven molecular motors. T2 - Gordon Research Conference - Artificial Molecular Switches & Motors CY - Holderness, NH, USA DA - 11.06.2017 KW - Rotaxane KW - Immobilization KW - XPS KW - NEXAFS PY - 2017 AN - OPUS4-42843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hupatz, H. A1 - Schröder, H. V. A1 - Heinrich, Thomas A1 - Schalley, C.A. A1 - Unger, Wolfgang T1 - Redox-Switchable Rotaxanes on Surfaces N2 - Nature has created molecular machines which can perform a variety of different tasks. They exhibit defined operational pathways and order, resulting in directed macroscopic effects. Within the last decades researchers have been developing numerous artificial molecular machines which are so far mostly operating in solution. However, this represents a major obstacle for the generation of a macroscopic output, due to the random orientation of molecules in solution. As a general approach to this problem, interfaces have been used to generate ordered arrays of functional molecules. Recently, we developed a new class of redox-switchable crown ether/ammonium-based [2]- and [3]rotaxanes which incorporate redox-active tetrathiafulvalene and naphthalene diimide units in their wheels resulting in emergent optoelectronic properties. Electrochemical stimuli influence the interactions between the two macrocycles of [3]rotaxanes and induce conformational changes. In a proof-of-principle study [2]pseudorotaxanes were deposited on gold surfaces by “click”-reaction to azide-terminated self-assembled monolayers to generate ordered arrays of redox-active rotaxanes on-surface. X-ray photoelectron spectroscopy (XPS) confirms the successful deposition of a rotaxane monolayer, though angle-resolved near-edge X-ray absorption fine structure spectroscopy (NEXAFS) exhibits poor order of the rotaxanes. Following, new terpyridine-stoppered rotaxanes will be synthesised opening a pathway for the deposition of [2]- and [3]rotaxanes in a layer-by-layer metal-mediated self-assembly procedure. This approach would allow for a programmed sequence of different rotaxanes in multilayers. Electrochemical on-surface switching will be investigated by angle-resolved NEXAFS spectroscopy, XPS, cyclic voltammetry and UV/Vis spectroscopy. A more detailed understanding of the electron-transfer between the surface and the different rotaxane layers as well as of the on-surface switching could give rise to potential applications like optoelectric data-storage devices or potential-driven molecular motors. T2 - GDCh-Wissenschaftsforum Chemie CY - Berlin, Germany DA - 10.09.2017 KW - NEXAFS KW - Rotaxane KW - XPS KW - Surface characterization PY - 2017 AN - OPUS4-42848 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Detjens, Marc A1 - Hübert, Thomas A1 - Tiebe, Carlo A1 - Banach, Ulrich T1 - Temperature influence on coulometric trace humidity measurement N2 - Coulometric sensors were tested in humidified synthetic air at various gas temperatures. Generated frost point temperature in the gas ranged from -30 °C to -60 °C and were measured by coulometric sensors and in addition by a calibrated dew point hygrometer. The gas temperatures, which were measured by a calibrated Pt100 sensor, were set to -20 °C, 0 °C, 23 °C, 40 °C, 50 °C, and 60 °C during the experiments. Empiric nonlinear functions were calculated between the humidity and the sensor signal. In comparison to the measured signals at 23 °C, the sensor signals were lower at the other gas temperatures. Measurements at 60 °C showed indistinct results due to a great signal noise. The response behavior of the sensors was similar at 23 °C, 40 °C and 50 °C. In contrast to that, the sensors reacted slowly at a gas temperature of -20 °C and 0 °C. In summary, with coulometric sensors it was possible to measure continuously trace humidity with an expanded uncertainty below 2 K. T2 - IEEE Sensors 2017 CY - Glasgow, Scotland, UK DA - 30.10.2017 KW - Coulometric sensors KW - Trace humidity measurement KW - Temperature influence KW - Chemical reaction KW - Response behavior PY - 2017 AN - OPUS4-42756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiel, Erik T1 - Novel thermographic methods for non-destructive testing using structured illumination N2 - Photothermal imaging is commonly used for the characterization of material properties, the determination of layer thicknesses or the detection of inhomogeneities such as voids or cracks. For this purpose, the solid specimen is externally heated, e.g. by using a light source. The resulting transient heat flows interact with the inner structures of the specimen, which in turn is measured as a transient temperature distribution at the surface. Novel array-shaped, high-power laser light sources allow to control the heating of the surface arbitrarily, both temporally and spatially. This enables us to shape the heat flows within the material in a very specific way. In a first application, we demonstrate how to apply destructively interfering thermal wave fields in order to detect subsurface defects with a very high sensitivity. A similar technique, although originating from a very different physical domain, is already in use for medical 3D imaging showing the high potential of this approach. T2 - Adlershofer For­schungs­forum 2017 CY - Berlin, Germany DA - 10.11.2017 KW - Active thermography KW - Photothermal KW - Crack detection KW - Thermal wave KW - Structured heating PY - 2017 AN - OPUS4-42835 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Keller, Julia A1 - Haase, H. A1 - Koch, Matthias T1 - Coupling of electrochemistry with LC/MS for generation and identification of mycotoxin oxidation products N2 - Mycotoxins cause a variety of mold-related health risks which makes it necessary to further examine their metabolic pathways in human and other mammals. Beside standard in vitro assays with liver cell microsomes an increasing interest in new and rapid simulation techniques are playing a growing role in mycotoxin research. Herein, the coupling of electrochemistry with liquid chromatography and mass spectrometry (EC/LC/MS) is presented as fast and simple method to investigate the oxidative fate of mycotoxins. For this case study, two food relevant mycotoxins (zearalenone and citrinin) were selected. Experiments were performed by using an electrochemical flow through cell integrated in the flow path of the autosampler of the chromatographic system. The reaction mixture was separated by a RP-C18 column and analyzed by a single quadrupole MS (Figure 1). Oxidation products were generated by applying potentials of 400, 800, 1200 and 1600 mV vs Pd/H2 using a glassy carbon working electrode. Different oxidation reactions like hydroxylation, dehydrogenation and dimerization lead to a diverse product pattern of the investigated mycotoxins. In a comparative study, electrochemical generated reaction products were compared with metabolites produced by human and rat liver microsomes in vitro. The obtained data show that EC/LC/MS is a versatile and promising tool in mycotoxin research to support metabolic investigations of known and unknown mycotoxins. T2 - Mycotoxin Workshop CY - Bydgoszcz, Poland DA - 19.06.2017 KW - Electrochemistry KW - Mycotoxin KW - LC/MS KW - Oxidation PY - 2017 AN - OPUS4-40779 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Riaz, Muhammad A1 - Kosslick, H. A1 - Ibad, F. A1 - Al-Otabi, R. A1 - Al-Otabi, F. A1 - Jäger, Christian A1 - Schulz, A. T1 - Effect of modification on acidity and porosity of natural zeolite clinoptilolite N2 - 1. Introduction Catalytic processing of heavy feedstock can meet the increased demand of energy up to a great extent. It requires the application of acidic catalysts like zeolites. However, the used synthetic catalysts are difficult to recover and reuse and are mostly spent. The use of natural zeolite as spent catalysts may open new perspectives in the chemical use of heavy feed feedstock by chemical conversion. Natural zeolites are not expensive, widely available and environment friendly. Clinoptilolite is a natural, most abundant medium pore size zeolite, consisting of 2-deminsional pore system containing of oxygen-8- membered and oxygen-10-membered rings.Although clinoptilolite is porous and can be acidified by ion exchange or acid treatment. Samples were characterized by XRD regarding crystallinity and phase composition. The acidity was studied by ammonia-TPD measurements and 1H solid state MAS NMR as well as REDOR experiments. Structure and structural changes caused by applied modifications were studied by 27Al- and 29Si MAS NMR measurements and thermal analysis. 2. Experimental Part The ion exchange behaviour of natural zeolite tuff contained ca. 90 ma. % of clinoptilite was studied in 0.1 and 0.5 M ammonium nitrate solution and for comparison with HCl solution of similar concentration. The activation temperature was varied between 300-600°C.The catalytic test was performed using ca. 0.2 g of the catalyst and ca.10g of the aldehyde and alcohol using toluene as solvent and under reflux. Reaction water was removed via a by-pass. 3. Results and discussion The experiments show that a part of the cations of clinoptilolite readily exchange with ammonium ions and protons supplied by acid treatment. Substitution of the compensating cations by NH4+ followed by calcination and HCl treatment does not produce structural changes in the original material, but it opens the channels and increases acidity and thermal stability. Calcination at higher temperature and exchange with concentrated acid has a more severe impact on the clinoptilolite structure dealumination as indicated by the appearance of 5- and 6-fold coordinated aluminum. Catalytic activity of sample is related to the surface acidity. The presence of acidic protons of medium to strong strength is confirmed by ammonia-TPD and proton NMR measurements. 4. Conclusions Acidic natural clinoptilolite catalysts prepared via ammonium exchange followed by calcination and acid treatment shows a positive influence on acidity and porosity. Modification creates hierarchical micro-nano porosity. The specific surface area varies between ca. 45 m2/g and 245 m2/g. T2 - Catalysis summer school-UK CY - Liverpool, UK DA - 17.07.2017 KW - Natural Zeolite Clinoptilolite PY - 2017 AN - OPUS4-40689 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sahre, Mario A1 - Mitzkus, Anja A1 - Beck, Uwe A1 - Köppe, Enrico A1 - Bartholmai, Matthias A1 - Basedau, Frank A1 - Hofmann, Detlef A1 - Gong, Xin A1 - Schukar, Vivien T1 - Electroplated magnetostrictive actuator layer enabling the external diagnosis of strain sensors N2 - Embedded fibre-opticaloptical strain sensors are suitable for structural health monitoring. In order to validate long-term performance (e.g.sensors integrated in airplane wings or wind power turbine blades) an external diagnostics is required. A strain-detecting region of the optical fibre, the fibre Bragg grating (FBG, is encased by a magnetostrictive layer system serving as actuator. For the validation of the correct sensor function, an external magnetic field introduces mechanical strain resulting in a defined shift of the Bragg wavelength. The layer system is realized by acombined PVD /ECD process optimized regarding magnetostrictive and mechanical properties. The long -term stability of layer adhesion and actuator function has been verified. T2 - 12. Thementage Grenz- und Oberflächentechnik (ThGOT) und das 5. Kolloquium Dünne Schichten in der Optik CY - Zeulenroda, Germany DA - 14.03.2017 KW - Magnetostrictive actuator layer KW - PVD /ECD process KW - Magnetostrictive layer KW - Strain sensors PY - 2017 AN - OPUS4-41800 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dörfel, Ilona A1 - Nofz, Marianne A1 - Sojref, Regine A1 - Schulz, Wencke A1 - Saliwan Neumann, Romeo A1 - Hesse, Rene A1 - Meyer, Christian A1 - Kranzmann, Axel T1 - Microstructure of alumina coating on steel P92 after thermal cycling N2 - 1. Introduction Alumina coatings are one possibility to increase the corrosion resistance, lifetime and application range of thermally loaded steel components, e.g. in modern power plants where the use of the Oxy-fuel technology corrosive fuel gas (H2O-CO2-O2-SO2 at 650 °C) affects the steel parts. In previous investigations the efficacy of protective alumina coatings on steel P 92 under those conditions was demonstrated. A shutdown and re-start of power plants or parts of them causes thermal stresses of the components which can cause detrimental effects like microstructural changes in the steel itself, changes in its oxidation behavior, delamination or microstructural changes in the coating. All those effects can lead to failure of the components, resulting in lifetime reduction. 2. Objectives As a first step, we concentrate on the influence of thermal cycling tests and observe the impact on the microstructure of the coating and the interface in laboratory air. These investigations will help understanding the processes which occur, show directions of potentially necessary changes of the coating due to improved thermal stress behaviour. 3. Materials & methods P 92 is a ferritic-martensitic steel, containing 9% Cr which forms protective Cr-oxide-rich scales in dry environments and non-protective ones in water-containing environments. Coupons of P 92, having ground surfaces, were dip-coated via a sol-gel process and subjected to thermal cycling for 500 h (1000 cycles) in laboratory air in a temperature range between room temperature and 660° C. The resulting mass loss was determined by weighing. Samples for TEM investigations were produced as cross sections normal to the sample surface by FIB preparation (Quanta 3D, (FEI)). The TEM/STEM investigations were performed using a JEM2200FS (JEOL) operated at 200 kV. The microstructure of the coating and the interface after cycling tests was characterized via TEM, HREM, and STEM images, electron diffraction as well as EDX and EFTEM methods. 4. Results At steep edges in the surface profile the coating was imperfect and cracks have formed during the thermal cycling. Flat surface regions are well-covered. The whole interface region between the steel and the coating shows a dense Cr-oxide-rich zone, which can form protective regions in case of local failure. The Cr-oxide zone is followed by a region of mixed oxides, containing Cr, Mn, Fe, and Al in variable composition, to which a porous δ-Al2O3 zone is joined. 5. Conclusions • Alumina coatings promote the formation of dense, Cr-rich zones at the interface, which makes the system self-healing. • These zones are stable during thermal stresses, even in regions with cracked coatings. • They cause reduction of outward diffusion and mass loss during thermal cycling. T2 - MC2017 CY - Lausanne, Switzerland DA - 21.08.2017 KW - Coating KW - Thermal cycling KW - TEM PY - 2017 UR - https://www.mc2017.ch/general-information/downloads/ AN - OPUS4-41724 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Wirth, Thomas A1 - Holzweber, Markus A1 - Pellegrino, F. A1 - Martra, G. T1 - Analysis of Fluorine Traces in TiO2 Nanoplatelets by SEM/EDX, AES and TOF-SIMS N2 - The synthesis of TiO2 nanoplatelets with fluorine-containing reactants is carried out using Ti (IV) butoxide as precursor and concentrated HF as shape controller, the final product requires a working up in order to eliminate or at least to reduce the amount of residual fluorides, which is realized here by well-defined thermal treatment. Qualitative investigation of the bulk elemental composition by means of EDX of TiO2 nanoparticles (NPs) has identified fluorine in case of the as-synthesized samples. EDX spectra of thermally treated products exhibit either a fluorine content close to the limit of detection. The latter holds also true for the reference sample, TiO2 NPs of bipyramidal shape and prepared by a different synthesis route. For differentiation whether fluorine is present in the bulk or at the surface of the TiO2 nanoplatelets, top-surface sensitive AES and ToF-SIMS has been applied. Secondary ions of fluorine are detected in ToF-SIMS spectra of all samples, but could be roughly quantified by measurement of same reference sample as for EDX, namely TiO2 nano-bipyramids. This revealed that the amount of fluorine within1 nm depth beneath the surface is reduced in the thermally treated specimen compared to the raw product down to a content about as low as in the reference sample. AES allows analyzing analysis of the first few nanometers from the top-surface of individual NPs by point analysis. An F KLL peak has been detected at the surface of samples of as-prepared TiO2 nanoplatelets under optimized measurement conditions, but was not detectable after their calcination, which is in agreement with ToF-SIMS results. Moreover, high resolution AES on single TiO2 nanoplatelets elucidated that the surface atomic layers surrounding the TiO2 nanopaltelet contain fluorides before thermal treatment of the NPs. T2 - 17th European Conference on Applications of Surface and Interface Analysis ECASIA 2017 CY - Montpellier, France DA - 24.09.2017 KW - Titania KW - Nanoparticles KW - Fluorine KW - SEM/EDX KW - Auger Electron Spectroscopy KW - Nanoplatelets PY - 2017 AN - OPUS4-42656 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Ortel, Erik A1 - Wirth, Thomas A1 - García, S. A1 - Martinez, A. A1 - Blanco, M. A1 - Alberto, Gabriele A1 - Borghetti, P. A1 - Jupille, J. A1 - Martra, G. T1 - Functionalization of TiO2 Nanoparticles and supports for Assembly of Multiple Porous Layers N2 - Self-assembly of TiO2 nanoparticles in multiple layers by layer-by-layer deposition has been selected of different deposition procedures usually applied for fabrication of TiO2 thin films with defined and homogeneous thickness on supports of interest for the large-scale applications. The substrates tested were: conductive (FTO) glass, silica glass and titanium alloy. The selected film fabrication technique consists of the deposition of alternating layers of oppositely charged, i.e. functionalized, TiO2 nanoparticle layers with wash steps in between. The controlled assembly of TiO2 nanoparticles on the supports surface requires both a proper functionalization of the supports to promote the adhesion of the TiO2 film to the substrates and proper functionalization of TiO2 nanoparticles to allow attachment to substrate and subsequent reaction between different NP layers. The current study focusses on the analytical control of the functionalization of the substrates with 3-Aminopropyltriethoxysilane (APTS) and glutaraldehyde (GA) by means of surface sensitive methods, XPS, Auger Electron Spectroscopy (AES) and ToF-SIMS. Chemical composition of surface of functionalized substrates shows differences in the degree and type of modification in dependence on substrate. T2 - European Conference on Applications of Surface and Interface Analysis ECASIA 2017 CY - Montpellier, France DA - 24.09.2017 KW - Functionalization KW - Substrates KW - Titania KW - Nanoparticles KW - SEM/EDX KW - XPS KW - Auger Electron Spectroscopy KW - ToF-SIMS PY - 2017 AN - OPUS4-42658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Griepentrog, Michael A1 - Reinstädt, Philipp A1 - Wollschläger, Nicole A1 - Zeigmeister, U. T1 - Size effects in electrodeposited Ni-coatings N2 - Polycrystalline Ni materials with grain sizes less than 100 nm (nano crystalline NC) and with grain sizes in the micrometer range (micro crystalline MC) in form of thin films have become important in many technologies due to their improved physical, chemical and mechanical properties. Usual the mechanical properties of such coatings are described by a Hardness value and a Young´s modulus measured by Instrumented Indentation Testing (IIT).The behavior of such coatings during indentation test is influenced by different size effects having their representative length scale – grain size, coating thickness, length that characterizes the depth dependence of the hardness (Indentation Size Effect ISE). To estimate realistic values for the intrinsic coating Hardness and Young´s modulus all size effects have to be considered. For this work thin nano crystalline Ni – coatings (average grain size 30 nm) with thickness from 1 μm to 5 μm were electrodeposited on brass substrates. Indentation tests in the continuous stiffness measurement (CSM) mode were provided on as prepared Ni – coatings using a G200 Nanoindentation system (Fa. Keysight). For estimation of the intrinsic hardness of the coatings from composite hardness values calculated from the measured force –displacement curve using the Oliver & Pharr method, the model described by Z.S. Ma [1] was used. It was found that the experimental data can be well described by the model. The fitted values for the intrinsic hardness and the fitting parameters will be given. The different values of intrinsic hardness and of length characterizing depth dependence of the hardness for different coating thickness are discussed as results of changes in the coating structure because of changes in deposition parameters. [1] Z.S. Ma, Y.C. Zhou, S.G. Long, C. Lu: On the intrinsic hardness of a metallic film/substrate system: Indentation size and substrate effects. International Journal of Plasticity 34 (2012) 1-11. This work is supported by European Metrology Program for Innovation and Research (EMPIR) (JRP 14IND03 Strength – ABLE) T2 - Conference: Nanomechanical Testing in Materials Research and Development CY - Dubrovnik, Croatia DA - 01.10.2017 KW - Size effect KW - Substrate effect KW - Electrodeposited Ni - coatings KW - Instrumented indentation testing PY - 2017 AN - OPUS4-42664 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosner, M. A1 - Vogl, Jochen A1 - Meixner, A. A1 - Kasemann, S. A1 - Noordmann, J. A1 - Rienitz, O. A1 - Schuessler, J. A1 - Kraft, R. A1 - Rabb, S. A1 - Vocke, R. T1 - Intercomparison of d26Mg Values in Mg Isotope RMs and Standards N2 - Accurate measurements of stable isotope abundance ratio variations are often reported using artifact based delta-scales, which rely on suitable isotopic reference materials (iRM) for their realization. For example, variations in the 26Mg/24Mg isotope abundance ratio in natural systems are typically reported as delta26Mg values that represents the relative difference between the 26Mg/24Mg ratio measured in a sample relative to its measurement preferably in an iRM. In the past, such delta26Mg measurements were referenced to NIST SRM 980, the initial zero of the delta26Mg scale. With the development of MC-ICPMS, the detection of small but measurable isotopic differences in different chips of SRM 980 became apparent. It was then replaced by a Mg solution (DSM3), the new zero of the delta26Mg scale. A potential replacement iRM for DSM3 has been developed, ERM-AE143. This iRM has also been measured for its absolute isotope amount ratios1,2 making it traceable to the SI. The results of a delta26Mg intercomparison experiment include the Mg iRMs SRM 980, IRMM-009, ERM-AE143, AE144, AE145 standards DSM3 and Cambridge-1. The intercomparison involved 5 expert laboratories, consisting of 3 national metrological institutes (BAM, NIST, PTB) and 2 scientific research laboratories (GFZ Potsdam, UBremen). The iRMs were measured relative to AE143 and cover a range of ≈5 ‰ in delta26Mg. IRMM-009 has the lowest delta26Mg value while DSM3 has the highest, spanning a range in values that covers natural Mg isotope variations. The 2SD reproducibilities of the individual values from the different laboratories range from 0.02 to 0.26 ‰. The mean delta26Mg values, calculated from the laboratory means however show 2SD reproducibilities varing between 0.025 and 0.093 ‰. Propagated measurement uncertainties suggest a standard uncertainty of about 0.1‰ for delta26Mg determinations. 1 JAAS, 2015, 31,179; 2JAAS, 2016, 31, 1440 T2 - Goldschmidt Conference 2017 CY - Paris, France DA - 13.08.2017 KW - Iisotope reference materials KW - Delta values KW - Magnesium isotope PY - 2017 AN - OPUS4-42742 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ickert, Stefanie A1 - Riedel, Jens A1 - Beck, S A1 - Linscheid, M.W. T1 - Collision Specific Fragmentation of Oligonucleotides in Tandem Mass Spectrometry N2 - Tandem MS experiments allow the fast acquisition of spectral datasets with enormous size and unprecedented content of information. The most commonly used method is undoubtedly collision induced dissociation (CID). The relatively young technical adaptation of CID to modern day Orbitrap experiments needs a higher confinement voltage and has accordingly been named higher-energy collisional dissociation HCD. Despite the name the absolute value of transferred energy per collision in HCD is lower than in CID. Since for many proteins CID and HCD result in comparable fragmentation patterns the two techniques are often treated as interchangeable. This approach is, however, not without pitfalls as other classes of biomolecules often exhibit strongly pronounced fragmentation specificity. As an example, MS/MS experiments on several 4-mer oligonucleotides were conducted employing both collision methods and the results were thoroughly compared. It is apparent that not only the total fragment yield but also the identity of the observed fragments differ significantly between the two methods. T2 - Jahrestagung der Deutschen Gesellschaft für Massenspektrometrie DGMS CY - Kiel, Germany DA - 05.03.2017 KW - Tandem MS KW - DNA KW - Mass Spectrometry PY - 2017 AN - OPUS4-42328 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Mielke, Johannes A1 - Babick, F. A1 - Ullmann, C. T1 - Evaluation of particle sizing techniques for implementation of the EC Definition of a nanomaterial N2 - Many techniques are available for measuring particle size distribution. For ideal materials (spherical particles, well dispersed) it is possible to evaluate the Performance of these methods. The performance of the analytical instrumentation for the purpose of classifying materials according to EC Definition is unknown. In this work the performance of commercially available particle sizing techniques on representative NanoDefine set of real-world testing materials (RTM) and quality control materials (QCM) for the implementation of the Definition is evaluated. T2 - Final NanoDefine Outreach Event Classification of nanomaterials according to the EU definition CY - Brüssel, Belgium DA - 19.09.2017 KW - Nanomaterial classification KW - Particle sizing techniques KW - Nanoparticles KW - EC definition of a nanomaterial PY - 2017 UR - http://www.nanodefine.eu/index.php/nanodefine-meetings/125-final-outreach-event-2017 AN - OPUS4-42507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Mielke, Johannes A1 - Dohányosová, P. A1 - Müller, P. A1 - López-Vidal, S. A1 - Hodoroaba, Vasile-Dan T1 - Electrospray as a sample preparation tool for electron microscopy: Toward quantitative evaluation of nanoparticles N2 - Electrospray ionization constitutes a promising deposition technique for high-resolution imaging. Particle distribution on TEM grids takes place homogeneously and no losses occur. Suspension must be appropriate (stabilizer may induce artefacts). ESI parameters need to be optimized for each material. T2 - Final NanoDefine Outreach Event: Classification of nanomaterials according to the EU definition CY - Brüssel, Belgium DA - 19.09.2017 KW - Electrospray deposition KW - Electron microscopy KW - Nanoparticles PY - 2017 UR - http://www.nanodefine.eu/index.php/nanodefine-meetings/125-final-outreach-event-2017 AN - OPUS4-42508 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Wohlleben, W. A1 - Mielke, Johannes A1 - Rauscher, H. T1 - Volume specific surface area (VSSA) by BET: concept and demonstration on industrial materials N2 - Volume specific surface area (VSSA) as measured by BET constituites a simple and reliable solution to (most) powders. Porous, coated, polydisperse/multimodal materials are to be treated with care, i.e. doubled by analysis with electron microscopy or more advanced BET analysis (e.g. t-plot)for each material in part. T2 - Final NanoDefine Outreach Event: Classification of nanomaterials according to the EU definition CY - Brüssel, Belgium DA - 19.09.2017 KW - VSSA KW - BET KW - Nanoparticles KW - Powder KW - Nanomaterial classfication PY - 2017 UR - http://www.nanodefine.eu/index.php/nanodefine-meetings/125-final-outreach-event-2017 AN - OPUS4-42509 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bremser, Wolfram A1 - Paul, Andrea T1 - Approaches to measurement uncertainty estimates for nominal properties N2 - Qualitative reference materials (RM) cover a wide range of the overall RM market. Proficiency testing providers attract up to a thousand of participants in PT schemes purely oriented on qualitative results. The RM used for these kinds of PT are poorly regulated, nevertheless with a more and more general acceptance of accreditation in the field of RM production and PT provision, there is an ever increasing interest in assessing producers and providers according to rules already well accepted in the field of quantitative analysis. The basic governing document, ISO 17034:2016, is written in a form that, at least for the overwhelming majority of requirements, may be applied to both qualitative and quantitative RM. However, problems remain. In particular, the expression of uncertainty of a purely qualitative result is still unresolved, and under discussion, the latter now lasting already dozens of years. Some handles would be needed. In the poster, existing approaches and some pragmatic, new ways to tackle the problem are displayed and discussed. T2 - Advanced Mathematical and Computational Tools for Metrology; AMCTM (XI) CY - Glasgow, Scotland, UK DA - 29 August 2017 KW - Nominal properties KW - Qualitative RM PY - 2017 AN - OPUS4-42467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Anja A1 - Swaraj, S. A1 - Sparnacci, K. A1 - Unger, Wolfgang T1 - Determining the shell thickness of PTFE@PS core@shell nanoparticles using scanning transmission x-ray microscopy (STXM) N2 - A scanning transmission x-ray microscopy (STXM) based methodology is introduced for determining the dimensions (shell thickness, core and total diameter) of core-shell nanoparticles which exhibit a strong x-ray absorption contrast and a well-defined interface between core and shell material. A low radiation dosage during data acquisition and, therefore, less x-ray beam induced damage of the sample is achieved by recording STXM images only at two predetermined energies of maximum absorption contrast, instead of recording a stack of images across the whole absorption edge. A model core-shell nanoparticle, polytetrafluoroethylene (PTFE) cores with polystyrene (PS) shell, is used for demonstration. Near edge x-ray absorption fine structure (NEXAFS) spectroscopy confirms the significant difference in x-ray absorption behavior between PTFE and PS. Additionally, due to the insolubility of styrene in PTFE a well-defined interface between particle core and shell is expected. In order to validate the STXM results, both the naked PTFE cores as well as the complete core-shell nanoparticles are examined by scanning electron microscopy (SEM). The introduced STXM based methodology yields particle dimensions in good agreement with the SEM results (deviation equal or less than 10%) and provides additional information such as the position of the particle core which cannot be extracted from a SEM micrograph. T2 - BAM PhD Day 2017 CY - Berlin, Germany DA - 21.09.2017 KW - STXM KW - SEM KW - PTFE KW - PS KW - Core-shell nanoparticles KW - Polymers KW - Metrology PY - 2017 N1 - Geburtsname von Müller, Anja: Hermanns, A. - Birth name of Müller, Anja: Hermanns, A. AN - OPUS4-42430 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Monks, Melissa-Jane A1 - Ritter, B. A1 - Würth, Christian A1 - Krahl, T. A1 - Kemnitz, E. A1 - Resch-Genger, Ute T1 - Rare earth strontium fluoride nanocrystals prepared via sol gel synthesis - Spectroscopic study of upconversion luminescence properties N2 - Obtaining high quality upconverting nanocrystals with only little crystal defects and hence, a high luminescence, affords a reliable synthesis route. Only this guarantees the reproducibility of the material and its spectroscopic properties required for future application. The fluorolytic sol-gel synthesis appears to be a convenient attempt, as this is a method with only few steps influencing the material properties, which can be well controlled. Also creating bright upconverting nanocrystals requires a profound understanding of the interplay of photophysical processes like multiphoton absorption, radiative and non-radiative pathways, and energy transfer in the material. Based on steady-state and time resolved luminescence measurements at different excitation power densities, the influence of the lanthanide doping ratio and synthesis parameters such as the annealing process on SrF2-nanocrystals obtained via the fluorolytic sol-gel synthesis was systematically studied. T2 - GDCh Wissenschaftsforum Chemie CY - Berlin, Germany DA - 10.09.2017 KW - Upconversion KW - Strontiumfluoride KW - Annealing study KW - Doping study KW - Luminescence PY - 2017 AN - OPUS4-42944 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sobol, Oded A1 - Steiner, S. A1 - Albe, K. A1 - Froemling, T. A1 - Unger, Wolfgang T1 - The characterization of oxygen diffusion in (Na1/2Bi1/2)TiO3 piezo-ceramics by Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) N2 - The ferroelectric ceramic NBT and its solid solutions with barium titanate (BT) are examples for the most promising lead free materials to substitute the dominant Pb(Zr,Ti)O3 (PZT). Lead based material should generally be disregarded due to environmental and health reasons. However, there is no class of lead-free piezoelectric materials that can replace PZT entirely. Not only the often inferior ferroelectric properties but also the lack of understanding of the defect chemistry of NBT is still a challenge for the replacement of lead containing piezo-ceramics. Just recently it could be shown by Li et al.[1] that NBT obtains extraordinarily high oxygen ionic conductivity when doped with Mg as acceptor. It was actually expected that doping just leads to a hardening of the ferroelectric properties. However, it became clear that the known defect chemical behavior of PZT cannot be extrapolated to NBT materials. Hence, to gain information on general doping effects a better defect chemical investigation is needed. This is particularly important for the applications with high reliability demands to investigate possible degradation and fatigue mechanisms. In the present work Time-of-flight-secondary ion mass spectrometry (ToF-SIMS) was used in order to observe the influence of different acceptor dopants (Fe, Ni, Al) on the oxygen diffusion in NBT. ToF-SIMS holds the ability to gain a full elemental distribution in a sub-micron resolution and was therefore chosen to provide the essential information on the favorable diffusion paths of oxygen in NBT in dependence of the chosen doping element. 18O was used as a tracer for oxygen as its natural abundance is only 0.2%. The doped NBT samples have been annealed for 5 h at 500°C in a 0.2 bar 18O-tracer atmosphere to be able to detect oxygen ion diffusion. ToF-SIMS investigations were conducted on a ToF-SIMS IV (ION TOF GmbH, Münster, Germany) using a Bi+ primary ion beam (25KeV in collimated burst alignment mode with a beam diameter of ~150 nm) and a Cs+ sputter beam (3KeV). The results illustrate the different impact of dopants on the diffusion properties which is evidence for a highly non-linear dependence on dopant type and concentration. 1) Li, M., et al., Nature Materials, 2014. 13(1): p. 31-35. T2 - 21st International Conference on Secondary Ion Mass Spectrometry - SIMS21 CY - Krakow, Poland DA - 10.09.2017 KW - NBT-Piezoceramics KW - ToF-SIMS PY - 2017 UR - http://sims.confer.uj.edu.pl/boa_poster.php?id=93 AN - OPUS4-42863 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cohen, Zina A1 - Bonnerot, Olivier A1 - Schlanger, J. A1 - Hahn, Oliver A1 - Rabin, Ira T1 - Ink analysis in Cairo Geniza fragments N2 - The Cairo Geniza is an “archive” discovered in the 19th century in Ben Ezra Synagogue in Fustat, a district in Old Cairo (Egypt), located south of the center of modern Cairo. The giant collection of mostly Jewish documents that vary in genres, languages and writing supports contains a large number of early medieval Hebrew manuscripts, mostly in fragmentary form. The larger part of the Cairo Geniza is stored today in the Cambridge University Library. The Geniza provides sources for the literary, linguistic, historical studies of the various aspects Jewish life. As the documents attest, at least two Jewish communities co-existed in Fustat up to 11th century: a so-called Babylonian and Palestinian. These communities had different leaders, different traditions and lived independently. The differences seem to manifest themselves also in the paleographical, codicological and some material properties of the manuscripts produced by each community. My work addresses the ink composition in the documents attributed to the members of these communities. For the determination of the inks type and composition I employ reflectography and µ-XRF spectrometry, respectively. The preliminary typological studies indicate that iron-gall inks were found predominantly in the manuscripts attributed to the Palestinian community. T2 - Konferenz WCJS CY - Jerusalem, Israel DA - 06.08.2017 KW - Ink KW - Manuscript KW - XRF analysis PY - 2017 AN - OPUS4-46041 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Breitfeld, Steffen A1 - Scholz, Gudrun A1 - Emmerling, Franziska A1 - Kemnitz, Erhard T1 - High energy ball milling of a new representative of coordination polymers without organofluorine linkers N2 - Metal organic frameworks and coordination polymers play an important role in different fields of applications. Moreover, particularly fluorinated metal-organic frameworks (FMOFs) are in the focus of interest during the last years. In most cases, fluorine is implemented using perfluorinated organic linkers at the synthesis, usually performed by solvothermal synthesis. However, only few examples are known so far where fluorine is coordinated directly to the metal cation. Recently, we reported about mechanochemical syntheses and characterization of fluorine-containing coordination polymers of alkaline earth metals by milling M(OH) (M: Ca, Sr, Ba) with fluorinated benzene dicarboxylic acids 2 and we reported about mechanochemical syntheses of alkaline earth metal fluorides with ammonium fluoride. Now we are reporting about a combination of both synthesis routes. That is the first mechanochemical synthesis of coordination polymers where fluorine is coordinated directly to the metal cation. T2 - Konferenz CY - Berlin, Germany DA - 30.11.2017 KW - Metal organic frameworks KW - Coordination polymer KW - Mechanochemical syntheses KW - Direct fluorine-metal bond KW - Alkaline earth metal PY - 2017 AN - OPUS4-46898 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Oesch, Tyler A1 - Weise, Frank A1 - Meinel, Dietmar A1 - Krütt, Enno T1 - In-situ analysis of water transport in concrete completed using X-ray computed tomography N2 - The water-transport characteristics of concrete have a major impact on its resistance to damaging chemical processes such as Alkali-Silica-Reaction (ASR). Water transport in samples of damaged and undamaged concrete was measured using in-situ CT. The resulting measurements of water-front movement relative to time and the change in 3D-moisture distribution within the samples, are needed for calibration and validation of water-transport numerical models. T2 - 3rd International Conference on Tomography of Materials and Structures CY - Lund, Sweden DA - 26.06.2017 KW - X-ray computed tomography (CT) KW - In situ KW - Water transport KW - Alkali-silica-reaction (ASR) PY - 2017 AN - OPUS4-40876 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Ortel, Erik A1 - Wirth, Thomas A1 - Holzweber, Markus A1 - Pellegrino, F. A1 - Martra, G. T1 - Analysis of fluorine traces in TiO2 nanoplatelets by SEM/EDX, AES and TOF-SIMS N2 - Hydrothermal synthesis of anatase TiO2 nanosheets with a high fraction of exposed {001} facets and related high photocatalytic activity - as an alternative to bipyramidal anatase TiO2 nanoparticles mainly exposing the {101} facets. The scope of the material preparation work is the thermal reduction of residual fluorides from HF (capping agent) induced during the synthesis of TiO2 nanosheets by calcination at 873K. The analytical task consists of detection and localization of fluorine present at the surface and/or in the bulk of TiO2 nanosheets before and after calcination by SEM/EDX, Auger electron spectroscopy and ToF-SIMS. T2 - Microscopy & Microanalysis 2017 Meeting CY - St. Louis, MO, USA DA - 06.08.2017 KW - Nanoplatelets KW - Fluorine KW - SEM/EDX KW - Auger electron spectroscopy KW - ToF-SIMS KW - TiO2 PY - 2017 AN - OPUS4-41579 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Mielke, Johannes A1 - Dohányosová, P. A1 - Müller, P. A1 - López-Vidal, S. T1 - Electrospray as a sample preparation tool for electron microscopic investigations: Toward quantitative evaluation of nanoparticles N2 - The potential of electrospray deposition, for the controlled preparation of particles for imaging in electron microscopes, is evaluated on various materials: from mono-modal suspensions of spherical particles to multimodal suspensions and to real-world industrial materials. It is shown that agglomeration is reduced substantially on the sample carrier, compared with conventional sample preparation techniques. For the first time, it is possible to assess the number concentration of a tri-modal polystyrene suspension by electron microscopy, due to the high Deposition efficiency of the electrospray. We discovered that some suspension stabilizing surfactants form artifact particles during electrospraying. These can be avoided by optimizing the sprayed suspension. T2 - Microscopy & Microanalysis 2017 Meeting CY - St. Louis, MO, USA DA - 06.08.2017 KW - Electrospray deposition KW - Nanoparticles KW - Electron microscopy KW - Sample preparation KW - TEM KW - SEM PY - 2017 AN - OPUS4-41578 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beckmann, Jörg A1 - Spranger, Holger A1 - Bär, Sylke T1 - THz-TDS-SAFT for the detection of inherent discontinuities in dielectric materials N2 - X-ray computed tomography (CT) model holds only for THz-TDS reconstruction if minor refraction index differences between the inhomogeneities and the surrounding material matrix exist. A Time Domain SAFT algorithm has been developed to overcome the restrictions. THz time domain measurement on representative sample sets with inherent artefacts were performed to use them for the Image reconstructions. The results will be presented and compared with optical surface images of the used test objects to evaluate the SAFT algorithm in relation to the reconstruction quality. T2 - 42nd International Conference on Infrared, Millimeter and THz waves CY - Cancun, Mexico DA - 27.08.2017 KW - THz-time-domain spectroscopy KW - SAFT KW - Tomography PY - 2017 AN - OPUS4-42034 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rühlmann, Madlen A1 - Büchele, Dominique A1 - Ostermann, Markus A1 - Schmid, Thomas A1 - Paul, Andrea T1 - Design of an online-analysis technique for the determination of major and minor nutrients in soils using DP-LIBS N2 - LIBS (laser-induced breakdown spectroscopy) is known as a fast and simultaneous multi-element analysis with little or no sample preparation. Because of that, over the last few years there has been a growing interest in applications of LIBS in the field of agriculture. As part of the National Research Strategy BioEconomy 2030 the German Federal Ministry of Education and Research (BMBF) started an innovation programme called BonaRes. BonaRes consists of ten interdisciplinary research project as-sociations which are dealing with soil as a sustainable resource for the bio-economy. One of these research projects is I4S (intelligence for soil) which has the goal to develop an integrated system for site-specific soil fertility management. This system includes a sensor platform, which contains different sensors, like XRF, VIS-NIR, Gamma and LIBS. The main task of LIBS measurements in this project is the real time determination of the elemental contents of major and minor nutrients in soils, like calcium, magnesium, potassium. For this purpose, a special setup has been designed. The sample uptake operates with the help of a rotatable sample plate, on which the loose soil sample can be placed in form of a track. The sample plate circulates with different velocities to simulate the application on the field. To provide a higher intensity and a better re-producibility of the obtained signal, a double-pulse Nd:YAG laser (1064 nm) was used. In order to minimize dust formation from the soil during the operation of the laser, a dust removal by suction has been integrated When using relative methods such as LIBS, a suitable calibration curve is needed for absolute quantification. Within the I4S project a large number of soil samples from different testing grounds with known data of chemical composition, texture etc. is available. For the first calibration curves seven soil samples from different grounds in Germany were prepared as reference materials and four certified reference materials from China and Canada were purchased. With the help of these reference materials, calibration curves for different elements were initially calculated based on internal standard addi-tion. Copper was used as internal standard because of its low concentration in soils. The complex matrix of soils, as well as the influence of moisture and grain size in soils makes the absolute quantification by LIBS challenging. To overcome these influences, a calibration curve based on multivariate analysis was generated. Therefore, baseline correction on the second derivative with a Savitzky-Golay filter was followed by a partial least squares regression (PLSR). Multivariate analysis leads to noise reduction and neglection of interfering signals. Therefore, a better correlation between signal intensity and nutrient concentration is observed and a robust calibration curve is obtained. T2 - 9. Euro-Mediterranes Symposium LIBS CY - Pisa, Italy DA - 11.06.2017 KW - LIBS KW - Soil KW - Matrix KW - Multi-element PY - 2017 AN - OPUS4-40807 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gebbers, R. A1 - Riebe, D. A1 - Beitz, T. A1 - Löhmannsröben, H.-G. A1 - Rühlmann, Madlen A1 - Schmid, Thomas T1 - Laser-induced breakdown spectroscopy (LIBS) for efficient quantitative determination of elemental plant nutrients in soils: A contribution to precision agriculture N2 - One important aim of precision agriculture (PA) is the optimization of crop growth by means of site-specific measures, e.g. fertilizer application. Thus, PA should contribute to a resource efficient and ecofriendly soil management. Due to the expenses associated with traditional methods of soil analysis, requiring sample collection and laboratory analysis, PA technologies are still not in widespread use. Therefore, the aim of the project “I4S – Integrated System for Site-Specific Soil Fertility Management” is the development of a field-deployed, sensor-based analysis system offering rapid, cost-effective and spatially-resolved fertilizer recommendations. In this system, laser-induced breakdown spectroscopy (LIBS) could be ideally suited to assessing elemental nutrient contents of soils. In addition to low cost, durability and small size, a reliable quantification procedure is a crucial requirement for such a system. However, the texture as well as the composition of the soil can affect the spectra. This matrix dependence is the key challenge to be addressed in the application of LIBS for soil evaluation. The focus of this work was the establishment of a LIBS method for soil analysis in a laboratory environment for future field application. Natural soil samples of various origins, textures and compositions were used to characterize the matrix dependence of the LIBS spectra. Reference samples were prepared by adding defined amounts of the target elements to the soils (standard addition). Signals not superimposed by peaks of other elements were identified for each element. The reference samples also provided calibration curves for the respective soil type when the initial concentrations in the soils were taken into account. Additionally, the common laboratory method ICP-OES following aqua regia extraction was used to obtain reference values. Various approaches of calibration free evaluation of the data were also evaluated. In addition to traditional single-pulse experiments, the advantages of dual-pulse LIBS in relation to signal intensity, reproducibility as well as overcoming the matrix dependence of soil spectra were investigated. These methods were subsequently applied to validation samples collected on a dense grid within a field. T2 - Pedometrics 2017 CY - Wageningen, The Netherlands DA - 26.06.2017 KW - LIBS KW - Precision KW - Agriculture KW - Soil KW - Site-specific PY - 2017 AN - OPUS4-40808 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nguyen, Thi Yen A1 - Bernardes, C. E. S. A1 - Minas da Piedade, M. E. A1 - Rademann, K. A1 - Emmerling, Franziska T1 - Guided crystallization: The influence of solvent and concentration N2 - Theoretical and experimental studies indicate that crystal nucleation can take more complex pathways than expected on the ground of the classical nucleation theory. A direct in situ observation of the different pathways of nucleation from solution is challenging since the paths can be influenced by heterogeneous nucleation sites, such as container walls. The custom-made acoustic levitator using in these experiments regulates the influence that solid surfaces, temperature, and humidity have on the crystallization process. The investigations of the crystallization process of paracetamol were performed with in situ analytical techniques and theoretical simulations to gain a comprehensive insight into processes, occurring intermediates, and required reaction conditions. The targeted choice of the solvent and the concentration enabled the guidance of the pathways, therefore, resulting in the isolation of one desired crystalline structure. T2 - Annual COST meeting CY - Lincoln, United Kingdom DA - 25.06.2017 KW - Crystallization KW - Polymorphism KW - Molecular dynamic simulation KW - Pair distribution function analysis KW - XRD PY - 2017 AN - OPUS4-41111 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Muhammad, Riaz A1 - Kosslick, H. A1 - Ibad, F. A1 - Jäger, Christian A1 - Schulz, A. T1 - Effect of the ammonium ion exchange and HCl treatment on the acidity of natural zeolite clinoptilolite N2 - Clinoptilolite is a natural, medium pore size, zeolite. It contains a 2-deminsional pore system containing of oxygen-8- membered and oxygen-10-membered rings. It is one of the most abundant natural zeolites. Clinoptilolite has a crystalline structure showing unique ion exchange and sorption properties. It is mainly used as ion exchanger and adsorbent for removal of toxic elements and compounds from the environment. The use of natural zeolite as spent catalysts may open new perspectives in the chemical use of heavy feed feedstock by chemical conversion. Natural zeolites are not expensive, widely available and environment friendly. Clinoptilolite is the most abundant natural zeolite. Although clinoptilolite is a potential acid catalyst, reports on its application in catalysis are limited so far. This contribution deals with the modification of the acidity of the natural zeolite clinoptilolite, the characterization of the acid sites and the catalytic activity in the Brønsted acid catalyzed acetalization of benzaldehyde with butandiol-1,3. The samples were acidified by via ammonium-ion exchange followed by calcination and acid treatment. The obtained catalysts were characterized by XRD regarding crystallinity and phase composition. The morphology was studied by TEM images The acidity was studied by ammonia-TPD measurements and 1H solid state MAS NMR as well as REDOR experiments. Structure and structural changes caused by applied modifications were studied by 27Al- and 29Si MAS NMR measurements and thermal analysis. The ion experiments show that a part of the cations of clinoptilolite readily exchange with ammonium ions and protons from HCl treatment. The NMR results give first hints for a relation of the catalytic conversion with the presence of 5-fold coordinated aluminum. The results will be discussed in terms of a collaborative action of Brønsted acid sites and 5-fold coordinated aluminum. T2 - Deutsche Zeolith Tagung-2017 CY - Frankfurt Germany DA - 01.03.2017 KW - Natural zeolite clinoptilolite PY - 2017 AN - OPUS4-40684 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -