TY - JOUR A1 - Strommer, Bettina A1 - Battig, Alexander A1 - Frasca, Daniele A1 - Schulze, Dietmar A1 - Huth, Christian A1 - Böhning, Martin A1 - Schartel, Bernhard T1 - Multifunctional Property Improvements by Combining Graphene and Conventional Fillers in Chlorosulfonated Polyethylene Rubber Composites N2 - The incorporation of nanoparticles like multilayer graphene (MLG) into elastomeric composites boosts their technical performance, such as their mechanical behavior and electrical conductivity. Common filler types (carbon black (CB) and aluminum trihydroxide (ATH)) generally fulfill single, specific purposes and are often used in high loadings. CB typically reinforces rubber mechanically, while ATH increases flame retardancy. Small amounts of MLG reduce these high filler contents and maintain the multifunctional characteristics of rubber composites. In chlorosulfonated polyethylene (CSM) + ATH, an intrinsically flame-retardant rubber was designed to achieve the highest standards such as maximum average of heat emission (MARHE) <90 kW m−2, 3 phrMLG was substituted for 15 phr CB and/or 3 phr ATH via an industrially applicable processing approach. Replacing either CB or ATH resulted in a property profile that was multifunctionally improved in terms of features such as mechanical performance, reduced sorption, and flame retardance. MLG nanocomposites are reported to show promise as an industrially utilizable route to obtain multifunctional high-performance rubbers. KW - Nanocomposites KW - Rubber KW - Multilayer graphene KW - Flame retardancy KW - Synergy KW - Nanoparticles KW - Elastomers PY - 2022 DO - https://doi.org/10.1021/acsapm.1c01469 SN - 2637-6105 VL - 4 IS - 2 SP - 1021 EP - 1034 PB - ACS Publ. CY - Washington, DC AN - OPUS4-54330 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strommer, Bettina T1 - Natural Rubber Nanocomposites via Optimized Latex Premixing and Conventional Technical Processing N2 - Creation of highly functional materials and replacement of high amounts of conventional fillers are driving forces for the development of nanocomposites. Besides the type and properties of nanoparticles, their dispersing in the elastomeric matrix and the stability of this dispersion through all processing steps are the main factors for the resulting performance of the produced material. Therefore, a preparation chain via latex premixing to a highly filled masterbatch, followed by conventional technical processing is to be developed. Three types of carbon-based particles are characterized as such (SEM, Raman Spectroscopy, BET specific surface area) and in combination with natural rubber, as nanocomposites (TEM. Hardness, Abrasion resistance, Compression set, Cone calorimetry). All of the studied particles lead to an improvement in the investigated mechanical properties, the extent of reinforcement depends strongly on the specific surface of the particle interacting with the elastomeric matrix in combination with their shape. T2 - DKG Elastomer Symposium CY - Online meeting DA - 28.06.2021 KW - Processing KW - Elastomers KW - Nanocomposites KW - Graphene KW - Nanoparticles KW - Latex KW - Natural rubber PY - 2021 AN - OPUS4-53106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Battig, Alexander T1 - Multifunctional Graphene in Flame Retarded Polybutadiene/ Chloroprene/ Carbon Black Composites N2 - Multilayer graphene is investigated as a multifunctional nanofiller to polybutadiene/ chloroprene rubbers (BR/CR) that partially substitutes carbon black (CB) and aluminum trihydroxide (ATH). Loadings of only 3 parts per hundred rubber (phr) MLG replaced 15 phr of CB and/or 3 phr of ATH in BR/CR nanocomposites. Mechanical and fire behavior were investigated, and results point to improved rheological, curing and mechanical properties of MLG-containing rubber composites. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - Graphene KW - Rubber KW - Fire Retardant KW - Nanofiller KW - Nanocomposite KW - ATH PY - 2021 AN - OPUS4-53202 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Harald T1 - Anwendungen von maschinellem Lernen und KI an der BAM N2 - Im Austausch mit den anderen Bundesoberbehörden wurden die KI-Ansätze der verschiedenen Bundesoberbehörden zu spezifischen Themen der Nanowissenschaften präsentiert. Der Vortrag der BAM fokusiert sich auf die Themen "Self driving lab", semantische Segmentierung und Auswertung von elektronenmikroskopischen Bildern sowie die Generierung von ausführbaren Machineninstruktionen aus natürlicher Sprache. Abschließend wird der neue BAM DataStore vorgestellt. T2 - Nano-Behördenklausur 2024 CY - Berlin, Germany DA - 03.07.02024 KW - Nano KW - Bundesoberbehörden KW - Künstliche Intelligenz KW - Neuronale Netzwerke KW - Elektronisches Laborbuch PY - 2024 AN - OPUS4-61819 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schartel, Bernhard ED - Hu, Y. ED - Wang, X. T1 - Influence of the Size and Dispersion State of Two-Dimensional Nanomaterials on the Fire Safety of Polymers N2 - Only the nano-scaled structure of the nanocomposite and the dispersion of nanoparticles within the polymer matrix harbor multifunctional potential including superior fire retardancy. Thus, this chapter focuses on the dispersion of nanoplates, based mainly on studies of layered silicates and graphene/graphene-related nanoplates. The nanostructure and properties of the nanocomposites are dependent mainly on thermodynamic and kinetic factors during preparation. Improving nano-dispersion often directly improves flame retardancy. Therefore, the modification of the nanoplates as well as the preparation of nanocomposites becomes very important to control this dispersion. The dispersion of nanoplates functions as a prerequisite for the formation of an efficient protective layer, changing the melt flow and dripping behavior, or the improvement of the char properties. KW - Nanocomposite KW - Flame retardancy KW - 2D nanoparticle KW - Exfoliation KW - Dispersion KW - Flammability PY - 2023 SN - 978-1-032-35268-8 SN - 978-1-032-35502-3 SN - 978-1-003-32715-8 DO - https://doi.org/10.1201/9781003327158-2 SP - 23 EP - 58 PB - CRC Press CY - Boca Raton AN - OPUS4-58290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Laskina, Sofya T1 - Computing the forward and inverse problem of X-ray scattering N2 - Continuing progress in the field of X-ray scattering methods empowers scientists with new possibilities to capture the most important piece of information about the structure of the sample - its 3D electron density. Although the first methods appeared almost a century ago, recovering the density structure of a sample is still very problematic. Most avail-able imaging techniques transform a 3D electron density of a realspace structure into the 2D Fourier Transform of the intensity of scattered waves in the reciprocal space. This process causes a loss of information. Firstly, instead of a 3D sample, a 2D image is created, and secondly, the phase information of the scattered waves is lost. The latter is known as the ”phase problem” and poses a serious obstacle on a way to recover a 3D electron density. In this work, we draw attention to the problem of forward and inverse Small Angle X-Ray Scattering. In the first, forward, part, we rethink the existing pipelines to computationally simulate such scattering experiments. Although there are efficient implementations of fast Fourier transformation, they often have some drawbacks. For instance, to calculate a 3D fast Fourier transform it is required to place its density in the RAM. For high-resolution structures of size > 1024 3 , this becomes very problematic, as the whole density structure requires more than 16 GB of memory. CUDA solution allows for a very fast and parallelizable implementation of high-resolution data on hundreds of last-generation machines. Such computations are very pricy and inaccessible for most scientists. To bypass this limitation, we propose a solution for a split-up 3D fast Fourier transform, which is implemented as a sequence of 2D and 1D operations. We compare our implementation on the simulated 3D shapes and show the result of a proof-of-concept on 4096 3 Metallorganic framework density structure. In the second, inverse problem, we train an invertible neural network, that given scattering data can predict the shape and its parameters. The architecture is built such, that the inverse problem is learned together with the forward process - the Fourier Transformation. We achieved very good results with this architecture, nonetheless, further testing is required, as the current training set only encompasses three simple shapes: sphere, hard sphere and cylinder. All code to reproduce and analyze the results is available at https: //github.com/sofyalaski/SAXS-simulations. KW - Machine Learning KW - SAXS KW - DFT PY - 2023 SP - 1 EP - 76 PB - Freie Universität Berlin CY - Berlin AN - OPUS4-56798 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Schmidt, Alexandra A1 - Bresch, Harald A1 - Kämpf, K. A1 - Bachmann, V. A1 - Peters, T. A1 - Kuhlbusch, T. T1 - Development of a specific OECD Test Guideline on Particle Size and Particle Size Distribution of Nanomaterials N2 - In this research project, a new OECD Test Guideline (TG) for the determination of “Particle Size and Particle Size Distributions of Nanomaterials” was developed as the existing OECD TG 110 is considered to be outdated in terms of applicable size range (not covering sizes <200 nm) and methods. By its scope with an applicable size range from 1 to 1000 nm the new Test Guideline (TG PSD) covers the whole nanoscale. The TG PSD is applicable for particulate and fibrous nanomaterials. The prescribed, pairwise measurement of fibre diameter and length in the TG PSD allows for the first time to differen-tiate fibres with regard to their size-dependent hazard properties. Measurement instructions for each included method were validated within two separated interlaboratory comparisons, as a distinction between near spherical particles and fibres when applying the methods has to be made. Besides information on content and structure of the TG PSD, this final report outlines essential steps, considerations and organisational aspects during the development of the TG. Insights into the selec-tion, preparation and prevalidation of test materials used in the interlaboratory comparison are given. Finally, main results of the interlaboratory comparisons and their impacts on the TG PSD are pre-sented. N2 - Im Rahmen des Forschungsprojekts wurde eine neue OECD-Prüfrichtlinie (TG) für die Bestimmung von Partikelgrößen und Partikelgrößenverteilungen von Nanomaterialien entwickelt, da die existie-rende OECD TG 110 zur Bestimmung von Partikelgrößen in Bezug auf den anwendbaren Größenbe-reich und die gegebenen Methoden veraltet ist bzw. den Nanometerbereich < 200 nm nicht abdeckt. Mit ihrem Anwendungsbereich von 1 bis 1000 nm deckt die neue Prüfrichtlinie (TG PSD) die gesamte Nanoskala ab. Die TG PSD ist für partikel- und faserförmige Nanomaterialien anwendbar. Durch die, in der TG PSD vorgeschriebene, paarweise Messung von Faserdurchmesser und -länge ermöglicht diese TG zum ersten Mal Fasern hinsichtlich ihrer größenabhängigen Gefahrstoffeigenschaften zu unter-scheiden. Die Messanweisungen aller enthaltenen Methoden wurden im Rahmen von zwei getrennten Ringversuchen validiert, da bei der Anwendung der Methoden eine Unterscheidung zwischen Parti-keln und Fasern gemacht werden muss. Neben Angaben zum Inhalt und Struktur der TG PSD, befasst sich der vorliegende Abschlussbericht mit den wesentlichen Schritten, Überlegungen und organisatorischen Aspekten bei der Entwicklung der Prüfrichtlinie. Darüber hinaus werden Einblicke in die Auswahl, Vorbereitung und Prävalidierung der im Ringversuch verwendeten Testmaterialien gegeben. Schließlich werden die wichtigsten Ergeb-nisse aus den Ringversuchen und ihre Auswirkungen auf die TG PSD vorgestellt. KW - Nano KW - OECD KW - Particle size distribution KW - Testguideline KW - Nanoparticle PY - 2021 VL - 2021 SP - 1 EP - 47 PB - German Environment Agency CY - Dessau AN - OPUS4-54021 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Piquemal, François A1 - Hoffmann, Johannes A1 - Gautier, Brice A1 - Hertwig, Andreas A1 - Frabricius, Norbert T1 - Publishable Summary for 20IND12 Elena Electrical nanoscale metrology in industry N2 - Consumer electronics, innovative quantum technologies, and Internet of Things applications all rely on semiconductors, where reliable characterisation of electrical properties at the nanoscale is essential for European innovation and competitiveness. The measurement of these properties allows the evaluation of critical parameters used to define the performance of electronic materials and components. Currently, Conductive Atomic Force Microscopes and Scanning Microwave Microscopes enable nanoscale electrical characterisation, but they are costly, complicated and, in many cases where they are used, unreliable as measurements are not traceable. The aim of the project was to make such measurements traceable for the first time, with stated uncertainties, and affordable by developing and testing cost effective instrumentation and the first “out of lab” reference standards from DC to GHz and by elaborating robust calibration methods and good practice guides using simplified uncertainty budgets. All the objectives were achieved. The project has successfully improved the user-friendly uncertainty quantification for the electrical measurements at the nanoscale in the industrial environment. The design of calibration standards has been improved and new standards for DC resistance / current as well as HF impedance have been introduced and quantified. Good practice guides for the calibration and uncertainty quantification have been written and will be available to the users’ community. New ways of determining the properties of standard samples like ellipsometry have been evaluated. The interaction with stakeholders and industry collaborators was very important for the consortium and several case studies were carried out with industry-relevant samples. All data, procedures, and example uncertainty data from the project are included into the standardisation process and two IEC standards projects have been started during this project. These standards will be used as one important dissemination ways for the results of the project. KW - Electrical Properties KW - Nanometrology KW - Scanning Probe Microscopy KW - Optical Surface Analysis PY - 2024 SP - 1 EP - 9 AN - OPUS4-61812 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bresch, Harald A1 - Schmidt, Alexandra A1 - Kämpf, K. A1 - Bachmann, V. A1 - Peters, T. A1 - Kuhlbusch, T. T1 - Draft OECD Test Guideline for the Testing of Chemicals - Particle Size and Particle Size Distribution of Nanomaterials N2 - Final Draft of the OECD Test Guideline for Particle Size and Particle Size Distribution of Nanomaterials. The OECD Working Party on Manufactured Nanomaterials (WPMN) has actively worked towards understanding possible safety issues for manufactured nanomaterials and has contributed significantly to resolving these by developing Test Guidelines, Guidance Documents, Test Reports and other publications with the aim of a safe use of manufactured nanomaterials. The OECD website (www.oecd.org/science/nanosafety) and the referenced publications contain more background information. Among others, the OECD Test Guideline “Particle Size Distribution/Fibre Length and Diameter Distributions” (TG 110, adopted in 1981) was identified to require an update to address the specific needs of manufactured nanomaterials as the TG 110 is currently only valid for particles and fibres with sizes above 250 nm. The WPMN prioritised to either update TG 110 to be applicable also to particles at the nanoscale or draft a new nanomaterial specific Test Guideline (TG). Eventually, it was decided to develop a new TG for particle size and particle size distribution measurements of nanomaterials covering the size range from 1 nm to 1000 nm for further justification. This TG overlaps with TG 110 in the size range from 250 nm to 1000 nm. When measuring particulate or fibrous materials, the appropriate TG should be selected depending on the size range of particles tested. In line with TG 110, the new TG for nanomaterials includes separate parts for particles and fibres. For the part of this TG which addresses particles, several methods applicable to nanomaterials were reviewed and included to take into account developments since 1981 when the TG110 was adopted. This TG includes the following methods: Atomic Force Microscopy (AFM), Centrifugal Liquid Sedimentation (CLS)/Analytical Ultracentrifugation (AUC), Dynamic Light Scattering (DLS), Differential Mobility Analysis System (DMAS), (Nano)Particle Tracking Analysis (PTA/NTA), Small Angle X-Ray Scattering (SAXS), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). For measuring the diameter and length of fibres, analysing images captured with electron microscopy is currently the only method available. This TG includes Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). To test the validity of this TG, an ILC was performed. Test materials were chosen to reflect a broad 68 range of nanomaterial classes, e.g. metals, metal oxides, polymers and carbon materials. Where possible, well-characterised test materials were used. Additionally, the test materials were chosen, so that they reflect a broad range of sizes representing the size range 1 nm to 1000 nm and finally, for fibres only, aspect ratios from length/diameter of 3 to > 50. KW - Nano KW - OECD KW - Test guideline KW - Nanomaterial KW - Nanoparticle PY - 2021 UR - https://www.oecd.org/chemicalsafety/testing/draft-test-guideline-particle-size-distribution-nanomaterials.pdf SP - 1 PB - Organisation for Economic Co-operation and Development CY - Paris AN - OPUS4-53828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bresch, Harald A1 - Schmidt, Alexandra A1 - Kämpf, K. A1 - Bachmann, V. A1 - Peters, T. A1 - Kuhlbusch, T. T1 - Test Guideline No. 125 - Nanomaterial Particle Size and Size Distribution of Nanomaterials N2 - The OECD Working Party on Manufactured Nanomaterials (WPMN) has actively worked towards understanding possible safety issues for manufactured nanomaterials and has contributed significantly to resolving these by developing Test Guidelines, Guidance Documents, Test Reports and other publications with the aim of a safe use of manufactured nanomaterials. To address the specific needs of manufactured nanomaterials, the OECD Test Guideline No. 110 “Particle Size Distribution/Fibre Length and Diameter Distributions” was identified as one of the test guidelines (TGs) to require an update. The current TG 110 (adopted in 1981) is only valid for particles and fibres with sizes above 250 nm. The WPMN prioritised to either update TG 110 to be applicable also to particles at the nanoscale or draft a new nanomaterial specific (TG). Eventually, it was decided to develop a new TG that covers the size range from 1 nm to 1000 nm, intended for particle size and particle size distribution measurements of nanomaterials. Paragraph 11 provides further justification on the need for such measurements for nanomaterials. This TG overlaps with TG 110 in the size range from 250 nm to 1000 nm. When measuring particulate or fibrous materials, the appropriate TG should be selected depending on the size range of particles tested. In line with TG 110, the new TG for nanomaterials includes separate parts for particles and fibres. For the part of this TG which addresses particles, several methods applicable to nanomaterials were reviewed and included to take into account developments since 1981 when the TG 110 was adopted. This TG includes the following methods: Atomic Force Microscopy (AFM), Centrifugal Liquid Sedimentation (CLS)/Analytical Ultracentrifugation (AUC), Dynamic Light Scattering (DLS), Differential Mobility Analysis System (DMAS), (Nano)Particle Tracking Analysis (PTA/NTA), Small Angle X-Ray Scattering (SAXS), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The method Single Particle Inductively Coupled Plasma Mass Spectrometry (sp-ICP-MS) could not be sufficiently validated within the interlaboratory comparison (ILC) carried out for the different methods in this TG (see also paragraph 6 for further details on the ILC). Applicability of sp-ICP-MS is strongly limited to nanomaterials with high mass values in combination with a sufficiently high particle size. However, the general method ICP-MS is widely used and the sp-mode for the size measurement of specific nanomaterials was successfully performed in ILCs elsewhere. The method is therefore included in the Appendix Part C of this TG, which further details the limitations of sp-ICP-MS. For measuring the diameter and length of fibres, analysing images captured with electron microscopy is currently the only method available. This TG includes Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). To test the validity of this TG, an ILC was performed. Test materials were chosen to reflect a broad range of nanomaterial classes, e.g. metals, metal oxides, polymers and carbon materials. Where possible, well-characterised test materials were used. Additionally, the test materials were chosen to reflect a broad range of sizes representing the size range 1 nm to 1000 nm. Specifically for fibres, a broad range of aspect ratios was included (length/diameter of 3 to > 50). Some of the test materials used are commercially available and further references are given in the validation report of the ILC. Sample preparation for physical chemical characterisation is critical for all listed methods. Due to the differences between individual nanomaterials and due to the wide range of individual material properties it is impossible to have a generic protocol to obtain the best possible sample preparation for every nanomaterial. Therefore, a generic protocol on sample preparation is not part of this TG. Information on sample preparation is given in the paragraphs 25-29, 33, 34 and 39 for particles and in paragraphs 159) for fibres. Further information on sample preparation of nanomaterials for physical chemical characterisation can be found in the OECD Guidance on Sample Preparation and Dosimetry for the Safety Testing of Manufactured Nanomaterials and elsewhere. KW - Nano KW - Nanomaterial KW - Nanoparticle KW - OECD KW - Test guideline PY - 2022 DO - https://doi.org/10.1787/20745753 SP - 1 EP - 72 PB - Organisation for Economic Co-operation and Development CY - Paris AN - OPUS4-55191 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kolmangadi, Mohamed Aejaz T1 - Dynamics and conductivity of nanoconfined amino acid based superdiscs: Influence of the side chain length N2 - Ionic Liquid Crystals (ILCs) are emerging class of materials that combine the properties of liquid crystals with the ionic conduction similar to ionic liquids. It’s known that liquid crystals exhibit intriguing properties when confined and are of importance from both fundamental and technological perspective. Here, we study the molecular dynamics and electrical conductivity of a homologous series of Dopamine (DOPA) based ILCs, ILCn (n = 12,14,16) confined in self ordered nanoporous alumina oxide membrane of 180 nm pore size using Broadband Dielectric Spectroscopy (BDS). We aim to understand how the alkyl chain length and confinement influence the dynamics in this system. In the bulk, for all ILCs, we observe two relaxation modes in the crystalline phase, the  and α1 relaxation respectively, and one relaxation mode in the columnar phase, the α2 relaxation, but for ILC16, where two relaxation modes (α2 and α3) are detected in the columnar phase. For the confined case, all relaxation processes slowdown compared to the bulk. For ILC16, the α1 relaxation is completely suppressed. For all ILCs, the absolute values of DC conductivity are reduced by some three orders of magnitude. We discuss in detail the possible molecular origin of the relaxation processes and the charge transport in this system. T2 - CONFIT 2022 CY - Grenoble, France DA - 10.10.2022 KW - Ionic Liquid crystals KW - Nanoconfinement KW - Conductivity PY - 2022 AN - OPUS4-57341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Bonse, Jörn A1 - Kirner, Sabrina V. A1 - Krüger, Jörg ED - Sugioka, K. T1 - Laser-induced periodic surface structures (LIPSS) N2 - Laser-induced periodic surface structures (LIPSS) are a universal phenomenon and can be generated on almost any material by irradiation with linearly polarized radiation. This chapter reviews the current state in the field of LIPSS, which are formed in a “self-ordered” way and are often accompanying materials processing applications. LIPSS can be produced in a single-stage process and enable surface nanostructuring and, in turn, adaption of optical, mechanical, and chemical surface properties. Typically, they feature a structural size ranging from several micrometers down to less than 100 nm and show a clear correlation with the polarization direction of the light used for their generation. Various types of LIPSS are classified, relevant control parameters are identified, and their material-specific formation mechanisms are analyzed for different types of inorganic solids, i.e., metals, semiconductors, and dielectrics. Finally, technological applications featuring surface functionalization in the fields of optics, fluidics, medicine, and tribology are discussed. KW - Femtosecond laser KW - Laser ablation KW - Laser-induced periodic surface structures (LIPSS) KW - Microstructures KW - Nanostructures PY - 2021 SN - 978-3-319-69537-2 DO - https://doi.org/10.1007/978-3-319-69537-2_17-2 SP - 1 EP - 59 PB - Springer Nature CY - Cham, Switzerland ET - 2 AN - OPUS4-51493 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liu, Y. A1 - Gruner, A. A1 - Aboud, D. G. K. A1 - Bonse, Jörn A1 - Schille, J. A1 - Loeschner, U. A1 - Kietzig, A.-M. T1 - Polarization effects on laser-inscribed angled micro-structures N2 - The polarization of the laser beam exhibits more substantial differences in laser micromachining as the angle of incidence deviates from zero. In the reported work, our focus was to explore the effects of circularly, p- and s-polarized laser on angled ultrashort pulse laser micromachining of micropillar arrays. The examination encompassed laser process factors, including angles of incidence, microstructure dimensions, and inter-pillar spacing. A comparison between the resulting structures demonstrated that p-polarized laser beam was the most efficient in material removal in angled laser micromachining, followed by circularly polarized laser. While the s-polarized beam exhibited the lowest ablation efficiency among the three. Such distinction is mainly attributed to the distinguishing reflectivity of the three states of polarization on tilted planes. The development of structural heights during ablation processes was examined, and potential defects in laser processing methodologies were interpreted. The dependency of structural heights on inter-pillar spacing was analyzed. This study bridges the gap between existing studies on angled ultrashort pulse laser machining and the influences of polarization on laser machining. The comparison between structures produced using laboratory-scale and industrial-scale laser systems also yielded pertinent recommendations for facilitating a smooth transition of angled laser micromachining from laboratory-scale research to industrial applications. KW - Laser processing KW - Laser-induced periodic surface structures (LIPSS) KW - Microstructures KW - Nanostructures PY - 2024 UR - https://www.sciencedirect.com/science/article/pii/S0169433223028714 DO - https://doi.org/10.1016/j.apsusc.2023.159191 SN - 0169-4332 VL - 649 SP - 1 EP - 15 PB - Elsevier AN - OPUS4-59329 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Omar, Hassan T1 - Investigations of Ultrathin Polymer Films Supported on Inorganic Substrates N2 - Interactions between a polymer and a substrate interface play a vital role in understanding the improvement in thin film material properties as well as serving as a model for nanocomposites. For any non-repulsive polymer-substrate interactions, polymer segments form an irreversibly adsorbed layer and show a slowdown in the glassy dynamics and thus an increase in the thermal glass transition temperature compared to the bulk-like values. The growth kinetics of the adsorbed layer showed a deviation for both poly (bisphenol-A carbonate) (PBAC) and polysulfone (PSU), two bulky polymers containing a functional group (phenyl ring) in the backbone. T2 - Royal Society of Chemistry (RSC) Online Poster Conference CY - Online meeting DA - 05.03.2024 KW - Adsorbed Layer KW - Thin Films KW - Atomic Force Microscopy KW - Ellipsometry PY - 2024 AN - OPUS4-59625 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kuchenbecker, Petra A1 - Lindemann, Franziska T1 - Particle size determination of a commercially available CeO2 nano powder - SOPs and reference data N2 - Compilation of detailed SOPs for characterization of a commercially available CeO2 nano powder including - suspension preparation (indirect and direct sonication), - particle size determination (Dynamic Light Scattering DLS and Centrifugal Liquid Sedimentation CLS) with reference data, respectively. For sample preparation and analysis by Scanning Electron Microscopy (SEM) of this powder see related works (submitted, coming soon). KW - Wet dispersion KW - Nano powder KW - Particle size KW - CeO2 KW - Ceria KW - DLS KW - CLS PY - 2023 DO - https://doi.org/10.5281/zenodo.10061079 PB - Zenodo CY - Geneva AN - OPUS4-58785 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kuchenbecker, Petra A1 - Lindemann, Franziska T1 - SOP and reference data for determination of the Volume-specific Surface Area (VSSA) of a commercially available CeO2 nano powder N2 - Detailed SOP and reference data for the determination of the VSSA of a commercially available CeO2 nano powder: specific (BET-) Surface Area by gas adsorption (Ar and N2) skeletal (true solid state) density by gas pycnometry. Estimation of the particle size by VSSA screening method. KW - Nano powder KW - VSSA KW - Volume specific surface area KW - Screening method KW - Ceria KW - CeO2 PY - 2023 DO - https://doi.org/10.5281/zenodo.10061235 PB - Zenodo CY - Geneva AN - OPUS4-58786 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Marc Benjamin T1 - BP150: Combined cell and nanoparticle models for TOPAS to study radiation dose enhancement by Monte-Carlo based particle scattering Simulations N2 - Dose enhancement by gold nanoparticles (AuNP) increases the biological effectiveness of radiation damage in biomolecules and tissue. To apply them effectively during cancer therapy their influence on the locally delivered dose has to be determined. Hereby, the AuNP locations strongly influence the energy deposit in the nucleus, mitochondria, membrane and the cytosol of the targeted cells. In this work, two newly developed continuous and discrete-geometric models for simulations of AuNP in cells are presented. We apply the presented models in Monte-Carlo particle scattering simulations to characterize the energy deposit in cell organelles by radioactive 198AuNP. They emit beta and gamma rays and are therefore considered for applications with solid tumors. Differences in local dose enhancement between randomly distributed and nucleus targeted nanoparticles are compared. Hereby nucleus targeted nanoparticels showed a strong local dose enhancement in the radio sensitive nucleus. T2 - DPG Frühjahrstagung CY - Dresden, Germany DA - 26.03.2023 KW - AuNP KW - Beta decay KW - Brachytherapy KW - Cancer treatment KW - Clustered nanoparticles KW - DNA KW - DNA damage KW - Dosimetry KW - Energy deposit KW - Geant4 KW - Geant4-DNA KW - Gold Nanoparticles KW - LEE KW - Livermore model KW - Low energy electrons KW - MCS KW - Microdosimetry KW - Monte-Carlo simulation KW - NP KW - OH radical KW - Penelope model KW - Radiation damage KW - Radiation therapy KW - Radiationtherapy KW - Radioactive decay KW - Radiolysis KW - Radiotherapy KW - Simulation KW - TOPAS KW - TOPAS-nbio KW - Beta particle KW - Particle scattering KW - Protein KW - Proteins PY - 2023 AN - OPUS4-57253 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Omar, Hassan T1 - Probing Nanoscale Relaxation Behavior in Thin Polymer Films N2 - The investigations into the complicated effects of film thickness on bulk properties of thin polymer films has yielded conflicting results. The reduction in molecular mobility, and with it an increase in the glass transition temperature, for thin films of poly (bisphenol A carbonate) (PBAC) was assigned to the formation of an adsorbed layer. The adsorbed layer was obtained by washing away the loosely bounded chains using a good solvent. Next, using atomic force microscopy (AFM), the thickness of each sample was measured after annealing for various times at three different annealing temperatures. The growth of this adsorbed layer was shown to deviate from the previously reported 2-step mechanism seen for other polymers. For PBAC, after very long annealing times at high temperatures the thin films were dewetted, where segments of the adsorbed layer were removed from the substrate. T2 - Royal Society of Chemistry (RSC) Poster CY - Online meeting DA - 28.02.2023 KW - Thin films KW - Adsorbed Layer KW - Broadband dielectric spectroscopy KW - Atomic force microscopy KW - Growth Kinetics PY - 2023 AN - OPUS4-57196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Arai, Marylyn Setsuko A1 - Kim, Hyunho A1 - Pascavis, Madeleine A1 - Cha, Baekdong A1 - Brambilla, Gabriel A1 - Cho, Young Kwan A1 - Park, Jinho A1 - Vilela, Raquel R. C. A1 - de Camargo, Andrea S. S. A1 - Castro, Cesar M. A1 - Lee, Hakho T1 - Upconverting Nanoparticle-based Enhanced Luminescence Lateral-Flow Assay for Urinary Biomarker Monitoring N2 - Development of efficient portable sensors for accurately detecting biomarkers is crucial for early disease diagnosis, yet remains a significant challenge. To address this need, we introduce the enhanced luminescence lateral-flow assay, which leverages highly luminescent upconverting nanoparticles (UCNPs) alongside a portable reader and a smartphone app. The sensor’s efficiency and versatility were shown for kidney health monitoring as a proof of concept. We engineered Er3+- and Tm3+-doped UCNPs coated with multiple layers, including an undoped inert matrix shell, a mesoporous silica shell, and an outer layer of gold (UCNP@mSiO2@Au). These coatings synergistically enhance emission by over 40-fold and facilitate biomolecule conjugation, rendering UCNP@mSiO2@Au easy to use and suitable for a broad range of bioapplications. Employing these optimized nanoparticles in lateral-flow assays, we successfully detected two acute kidney injury-related biomarkers-kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL)-in urine samples. Using our sensor platform, KIM-1 and NGAL can be accurately detected and quantified within the range of 0.1 to 20 ng/mL, boasting impressively low limits of detection at 0.28 and 0.23 ng/mL, respectively. Validating our approach, we analyzed clinical urine samples, achieving biomarker concentrations that closely correlated with results obtained via ELISA. Importantly, our system enables biomarker quantification in less than 15 min, underscoring the performance of our novel UCNP-based approach and its potential as reliable, rapid, and user-friendly diagnostics. KW - Biosensor KW - Upconverting nanoparticles KW - Lateral flow KW - Portable sensor KW - Kidney injury PY - 2024 DO - https://doi.org/10.1021/acsami.4c06117 SN - 1944-8244 VL - 16 IS - 29 SP - 38243 EP - 38251 PB - American Chemical Society (ACS) AN - OPUS4-60689 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Iannuzzi, Maurizio A1 - Chowdhary, Suvrat A1 - Fiedler, Holly A1 - Haoues, Kilian A1 - Schade, Boris A1 - Thünemann, Andreas A1 - Quaas, Elisa A1 - Koksch, Beate T1 - Rational design of polyfluorinated peptide-based materials: Self-assembly of an amphiphilic motif N2 - Generation of a pH sensitive amphiphilic block oligopeptide containing the bioactive function RGD and a library of derivatives varying the length of the hydrophobic core and the degree of side chain fluorination. Peptide rational design enables us to obtain desired features (pH sensitivity etc.). The introduction of fluorine alters a wide range of peptide properties such as secondary structure propensity, folding, thermal and metabolic stability and proteolytic resistance. The RGD function is highly effective at promoting the attachment of numerous cell types to a plethora of materials. This small sequence is the principal integrin-binding domain present within ECM proteins such as fiobronectin, vibronectin and fibrinogen. For this reason, RGD containing peptides offer several advantages for biomaterials applications. The use of RGD compared with native ECM proteins, minimized the risk of immune reactivity or pathogen transfer. Herein in this work, we present the peptide motif X6RGD and its fluoro-derivates for prospective receptor-specific drug delivery in cancer theraphy. Overall, our results demonstrate that high degree of fluorination achieved triggers a selective modification of peptide self-assembly dramatically improving the structural properties, the carrier suitability, enzimatic degradation profiles and cytotoxic features of the fluoropeptide conjugate(s). T2 - 37th European Peptide Symposium CY - Florence, Italy DA - 25.08.2024 KW - Nanostructure KW - SAXS KW - Small-angle X-ray scattering PY - 2024 SN - 1099-1387 VL - 30 IS - S2 SP - 247 EP - 248 PB - Wiley CY - New York, NY AN - OPUS4-62191 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -