TY - JOUR A1 - Karafiludis, Stephanos A1 - de Oliveira Guilherme Buzanich, Ana A1 - Kochovski, Z. A1 - Feldmann, Ines A1 - Emmerling, Franziska A1 - Stawski, Tomasz T1 - Ni- and Co-Struvites: Revealing Crystallization Mechanisms and Crystal Engineering toward Applicational Use of Transition Metal Phosphates JF - Crystal Growth & Design N2 - Industrial and agricultural waste streams (waste water, sludges, tailings, etc.) which contain high concentrations of NH4+, PO43–, and transition metals are environmentally harmful and toxic pollutants. At the same time, phosphorous and transition metals constitute highly valuable resources. Typically, separate pathways have been considered to extract hazardous transition metals or phosphate independently from each other. Investigations on the simultaneous removal of multiple components have been carried out only to a limited extent. Here, we report the synthesis routes for Ni- and Co-struvites (NH4MPO4·6H2O, M = Ni2+ and Co2+), which allow for P, ammonia, and metal co-precipitation. By evaluating different reaction parameters, the phase and stability of transition metal struvites as well as their crystal morphologies and sizes could be optimized. Ni-struvite is stable in a wide reactant concentration range and at different metal/phosphorus (M/P) ratios, whereas Co-struvite only forms at low M/P ratios. Detailed investigations of the precipitation process using ex situ and in situ techniques provided insights into the crystallization mechanisms/crystal engineering of these materials. M-struvites crystallize via intermediate colloidal amorphous nanophases, which subsequently aggregate and condense to final crystals after extended reaction times. However, the exact reaction kinetics of the formation of a final crystalline product varies significantly depending on the involved metal cation in the precipitation process: several seconds (Mg) to minutes (Ni) to hours (Co). The achieved level of control over the morphology and size makes precipitation of transition metal struvites a promising method for direct metal recovery and binding them in the form of valuable phosphate raw materials. Under this paradigm, the crystals can be potentially up-cycled as precursor powders for electrochemical or (electro)catalytic applications, which require transition metal phosphates. KW - Crystallization KW - Struvite KW - Nickel KW - Cobalt KW - Phosphorous recovery KW - Up-cycling KW - Aqueous synthesis PY - 2022 DO - https://doi.org/10.1021/acs.cgd.2c00284 VL - 22 IS - 7 SP - 4305 EP - 4315 PB - ACS Publications CY - Washington D.C. AN - OPUS4-55286 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bresch, Harald A1 - Hodoroaba, Vasile-Dan A1 - Schmidt, Alexandra A1 - Rasmussen, K. A1 - Rauscher, H. T1 - Counting Small Particles in Electron Microscopy Images — Proposal for Rules and Their Application in Practice JF - Nanomaterials N2 - Electron microscopy (EM) is the gold standard for the characterisation of the morphology (size and shape) of nanoparticles. Visual observation of objects under examination is always a necessary first step in the characterisation process. Several questions arise when undertaking to identify and count particles to measure their size and shape distribution. In addition to challenges with the dispersion and identification of the particles, more than one protocol for counting particles is in use. This paper focuses on precise rules for the counting of particles in EM micrographs, as this influences the measurement accuracy of the number of particles, thus implicitly affecting the size values of the counted particles. We review and compare four different, commonly used methods for counting, which we then apply in case studies. The impact of the selected counting rule on the obtained final particle size distribution is highlighted. One main aim of this analysis is to support the application of a specific, well-defined counting approach in accordance with regulatory requirements to contribute to achieving more reliable and reproducible results. It is also useful for the new harmonised measurement procedures for determining the particle size and particle size distribution of nanomaterials. KW - Nano KW - Particle size distribution KW - Nanoparticle KW - Nanomaterial KW - OECD PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551891 DO - https://doi.org/10.3390/nano12132238 SN - 2079-4991 VL - 12 IS - 13 SP - 2238 PB - MDPI CY - Basel AN - OPUS4-55189 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Even, Morgane A1 - Juritsch, Elevtheria A1 - Richter, Matthias T1 - Selection of gas standards, gas chromatography column and adsorbents for the measurement of very volatile organic compounds (C1–C6) in indoor air JF - Analytica Chimica Acta N2 - The ISO 16000-6 standard gives directions to adapt the analysis of volatile organic compounds (VOCs) in indoor and test chamber air to very volatile organic compounds (VVOCs). The same techniques with sorbent-based active sampling, thermal desorption and gas chromatography coupled with mass spectrometry (TD-GC/MS) should be used. However, VVOCs require gaseous standards, an adapted GC column and a reliable sampling adsorbent. This work presents experimental results to tackle those three experimental gaps. A stable standard gas mixture containing 47 VVOCs, 13 VOCs and an internal standard was successfully generated. It was employed to study the suitability of seven types of chromatography columns. The use of PLOT (Porous Layer Open Tubular) columns such as PoraBOND Q is well suitable for VVOC analysis. The recoveries of the 60 analytes on a total of 16 adsorbents and their combinations were determined: A combination of the graphitized carbon black Carbograph 5TD 40/60 and the carbon molecular sieve CarbosieveTM SII showed great recoveries for all analytes. Carbon molecular sieves adsorb water which can impair the analysis. A dry purge of the multi-sorbent in the sampling direction led to a complete water removal and promising recoveries of the analytes. KW - VVOC KW - VOC KW - ISO 16000-6 KW - Gas chromatography KW - Thermal desorption KW - Air sampling PY - 2023 DO - https://doi.org/10.1016/j.aca.2022.340561 SN - 0003-2670 VL - 1238 SP - 1 EP - 12 PB - Elsevier B.V. AN - OPUS4-56366 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gugin, Nikita A1 - Villajos Collado, José Antonio A1 - Feldmann, Ines A1 - Emmerling, Franziska T1 - Mix and wait – a relaxed way for synthesizing ZIF-8 JF - RSC Advances N2 - Herein we report the synthesis of a zeolitic imidazolate framework (ZIF-8) by an easy “mix and wait” procedure. In a closed vial, without any interference, the mixture of 2-methylimidazole and basic zinc carbonate assembles into the crystalline product with approx. 90% conversion after 70 h. The reaction exhibits sigmoidal kinetics due to the self-generated water which accelerates the reaction. KW - In-situ analysis KW - Mechanochemistry KW - MOF KW - Synthesis KW - ZIF-8 PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546841 DO - https://doi.org/10.1039/D2RA00740A VL - 12 SP - 8940 EP - 8944 PB - Royal Society of Chemistry AN - OPUS4-54684 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - James, G. L. A1 - Latif, M. T. A1 - Isa, M. N. M. A1 - Bakar, M. F. A. A1 - Yusuf, N. Y. M. A1 - Broughton, William A1 - Murad, A. M. A1 - Abu Bakar, F. D. T1 - Metagenomic datasets of air samples collected during episodes of severe smoke-haze in Malaysia JF - Data in Brief N2 - Transboundary emissions of smoke-haze from land and forest fires have recurred annually during the dry period (June to October, over the past few decades) in South East Asia. Hazardous air quality has been recorded in Malaysia during these episodes. Agricultural practices such as slash-and-burn of biomass and peat fires particularly in Sumatera and Kalimantan, Indonesia, have been implicated as the major causes of the haze. Past findings have shown that a diversity of microbes can thrive in air including in smoke-haze polluted air. In this study, metagenomic data were generated to reveal the diversity of microorganisms in air during days with and without haze. Air samples were collected during non-haze (2013A01) and two haze (2013A04 and 2013A05) periods in the month of June 2013. DNA was extracted from the samples, subjected to Multiple Displacement Amplification and whole genome sequencing (Next Generation Sequencing) using the HiSeq 2000 Platform. Extensive bio-informatic analyses of the raw sequence data then followed. Raw reads from these six air samples were deposited in the NCBI SRA databases under Bioproject PRJNA662021 with accession numbers SRX9087478, SRX9087479 and SRX9087480. KW - Forest fires KW - Haze Samples KW - NGS KW - Multiple Displacement Amplification PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528973 DO - https://doi.org/10.1016/j.dib.2021.107124 SN - 2352-3409 VL - 36 SP - 107124 PB - Elsevier Inc. CY - Amsterdam, Netherlands AN - OPUS4-52897 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bastuck, M. A1 - Baur, T. A1 - Richter, Matthias A1 - Mull, B. A1 - Schütze, A. A1 - Sauerwald, T. T1 - Comparison of ppb-level gas measurements with a metal-oxide semiconductor gas sensor in two independent laboratories JF - Sensors and Actuators B: Chemical N2 - In this work, we use a gas sensor system consisting of a commercially available gas sensor in temperature cycled operation. It is trained with an extensive gas profile for detection and quantification of hazardous volatile organic compounds (VOC) in the ppb range independent of a varying background of other, less harmful VOCs and inorganic interfering gases like humidity or hydrogen. This training was then validated using a different gas mixture generation apparatus at an independent lab providing analytical methods as reference. While the varying background impedes selective detection of benzene and naphthalene at the low concentrations supplied, both formaldehyde and total VOC can well be quantified, after calibration transfer, by models trained with data from one system and evaluated with data from the other system. The lowest achievable root mean squared errors of prediction were 49 ppb for formaldehyde (in a concentration range of 20–200 ppb) and 150 μg/m³ (in a concentration range of 25–450 μg/m³) for total VOC. The latter uncertainty improves to 13 μg/m³ with a more confined model range of 220–320 μg/m³. The data from the second lab indicate an interfering gas which cannot be detected analytically but strongly influences the sensor signal. This demonstrates the need to take into account all sensor relevant gases, like, e.g., hydrogen and carbon monoxide, in analytical reference measurements. KW - Indoor air quality KW - Volatile organic compounds KW - Calibration transfer KW - Selective quantification KW - Inter-lab comparison PY - 2018 DO - https://doi.org/10.1016/j.snb.2018.06.097 SN - 0925-4005 VL - 273 SP - 1037 EP - 1046 PB - Elsevier B.V. AN - OPUS4-45609 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hofmann, Michael A1 - Richter, Matthias A1 - Jann, Oliver T1 - Robustness validation of a test procedure for the determination of the radon-222 exhalation rate from construction products in VOC emission test chambers JF - Applied radiation and isotopes N2 - This study investigated the adaptation of the state-of-the-art test procedure for the determination of emissions of volatile organic compounds (VOC) from materials into indoor air to test for the radon exhalation from stony construction products. A complete robustness validation including all relevant parameters showed that the procedure can be well applied by testing institutes already holding available the required VOC testing infrastructure that solely needs to be complemented by calibrated commercial radon measurement instrumentation. When measurements of the radon exhalation from construction materials become mandatory by law, test capacity can easily be applied. This work can serve as a recommendation for the European standardisation that still is on hold in this point. KW - Radon exhalation KW - Construction products KW - Emission test chamber KW - Robustness validation KW - Standardisation PY - 2020 DO - https://doi.org/10.1016/j.apradiso.2020.109372 SN - 0969-8043 VL - 166 IS - 109372 SP - 1 EP - 8 PB - Elsevier CY - Amsterdam AN - OPUS4-51145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Richter, Matthias A1 - Juritsch, Elevtheria A1 - Jann, Oliver T1 - Determination of recovery rates of adsorbents for sampling very volatile organic compounds (C1-C6) in dry and humid air in the sub-ppb range by use of thermal desorption gas chromatography-mass spectrometry JF - Journal of Chromatography A N2 - The reliable measurement of very volatile organic compounds (VVOC) in indoor air by use of thermal desorption gas chromatography (TD-GC) in order to include them into evaluation schemes for building products even nowadays is a great challenge. For capturing these small molecules with carbon numbers ranging from C 1 –C 6 , strong adsorbents are needed. In the present study, recovery rates of nine suitable adsorbents of the groups of porous polymers, graphitised carbon blacks (GCB) and carbon molecular sieves (CMS) are tested against a complex test gas standard containing 29 VVOC. By consideration of the recovery and the relative humidity (50% RH), combinations of the GCB Carbograph 5TD, the two CMS Carboxen 1003 and Carbosieve SII as well as the porous polymer Tenax® GR were identified to be potentially suitable for sampling the majority of the VVOC out of the gas mix. The results reveal a better performance of the adsorbents in combination than being used alone, particularly under humid sampling conditions. The recovery rates of the chosen compounds on each adsorbent should be in the range of 80–120%. KW - VVOC KW - Indoor Air: Adsorbent performance KW - Recovery rate KW - Thermal desorption KW - Gas chromatography PY - 2020 DO - https://doi.org/10.1016/j.chroma.2020.461389 VL - 1626 SP - 1 EP - 9 PB - Elsevier AN - OPUS4-51106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seneschal-Merz, Karine A1 - Bücker, Michael A1 - Feldmann, Ines T1 - Low melting glasses for transparent and environmentally-resistant enamels JF - Glass Technology: European Journal of Glass Science and Technology Part A N2 - Today glass is broadly used in modern architecture. For indoor applications it is possible to produce decorated glass by using enamel colours and glass painting techniques without any problems. However, this is more limited for applications out of doors. Humidity and environmental pollution attack the surface of the coating and can damage it. There are only a few colours on the market which are resistant towards acids and bases until now. Additionally, most of those colours are opaque. To extend the colour palette, chemically resistant low melting coloured glasses are being developed which are transparent and intensively toned even in thin coating thicknesses. To achieve such an ambitious aim, many parameters have to combine and act in a complex manner. New compositions of lead borosilicate, zinc borosilicate and lead-zinc borosilicate glasses were produced and milled as powder. The thermal properties as well as the environmental stability were analysed. The influence of PbO and ZnO on the thermal properties and the environmental stability were investigated. Evaluation of the fusing results shows that the production and mixture of transparent vitreous enamels for the exterior side of glasses is possible. The tests made it clear that the original materials for making the vitreous enamels must be excellently ground and prepared to achieve a satisfactory result. The method to produce durable vitreous enamels for exterior application also seems to allow the production of glass colours. KW - Low melting glasses KW - Enamels KW - Heavy metal free KW - Corrosion KW - Chemical durability KW - Aging tests KW - Architecture KW - Colored glasses PY - 2019 DO - https://doi.org/10.13036/17533546.60.4.002 SN - 1753-3546 SN - 1753-3554 VL - 60 IS - 4 SP - 97 EP - 104 PB - Society of Glass Technology CY - Sheffield, UK AN - OPUS4-48835 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Even, Morgane A1 - Juritsch, Elevtheria A1 - Richter, Matthias T1 - Measurement of very volatile organic compounds (VVOCs) in indoor air by sorbent-based active sampling: Identifying the gaps towards standardisation JF - TrAC Trends in Analytical Chemistry N2 - The ISO 16000-6 standard describes a method for the determination of volatile organic compounds (VOCs) in indoor and test chamber air by sorbent-based active sampling, thermal desorption and gas chromatography coupled with mass spectrometry (GC/MS). It also gives directions to adapt this methodology to very volatile organic compounds (VVOCs). Indeed, toxicologically based guideline values are being implemented for these compounds and it becomes necessary to measure them. But a comprehensive and robust measurement method is lacking. This work highlights the points that still need to be explored towards the standardisation of a suitable procedure: investigations on sorbent combinations, the suitability of chromatography columns and the use of gaseous standards are required. The biggest challenge remains in the fact that strong sorbents adsorb water together with VVOCs. Water may impair the analysis and the optimal approach to eliminate it is still to be found and integrated into the sampling strategy. KW - Solvents KW - Air analysis KW - VOC KW - Thermal desorption KW - Gas chromatography KW - ISO 16000-6 PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-523919 DO - https://doi.org/10.1016/j.trac.2021.116265 VL - 140 SP - 116265 PB - Elsevier B.V. AN - OPUS4-52391 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Recknagel, Sebastian A1 - Bresch, Harald A1 - Kipphardt, Heinrich A1 - Resch-Genger, Ute A1 - Koch, Matthias A1 - Rosner, M. T1 - Trends in selected fields of reference material production JF - Analytical and bioanalytical chemistry N2 - For more than 110 years, BAM has been producing reference materials for a wide range of application fields. With the development of new analytical methods and new applications as well as continuously emerging more stringent requirements of laboratory accreditation with regard to quality control and metrological traceability, the demand and requirements for reference materials are increasing. This trend article gives an overview of general developments in the field of reference materials as well as developments in selected fields of application in which BAM is active. This includes inorganic and metal analysis, gas analysis, food and consumer products, and geological samples. In addition to these more traditional fields of application, developments in the areas of optical spectroscopy, particulary fluorescence methods, and nanomaterials are considered. T2 - 150 years BAM: Science with impact CY - Berlin, Germany DA - 01.01.2021 KW - Reference material KW - ISO REMCO KW - Gas analysis KW - Food KW - Nanomaterials KW - Fluorescence PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548407 DO - https://doi.org/10.1007/s00216-022-03996-7 SN - 1618-2642 SN - 1618-2650 VL - 414 IS - Topical collection: Analytical methods and applications in the materials and life sciences SP - 4281 EP - 4289 PB - Springer CY - Berlin AN - OPUS4-54840 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Richter, Matthias A1 - Horn, Wolfgang A1 - Juritsch, Elevtheria A1 - Klinge, A. A1 - Radeljic, L. A1 - Jann, Oliver T1 - Natural building materials for interior fitting and refurbishment - What about indoor emissions? JF - Materials N2 - Indoor air quality can be adversely affected by emissions from building materials, consequently having a negative impact on human health and well-being. In this study, more than 30 natural building materials (earth dry boards and plasters, bio-based insulation materials, and boards made of wood, flax, reed, straw, etc.) used for interior works were investigated as to their emissions of (semi-) volatile organic compounds ((S)VOC), formaldehyde, and radon. The study focused on the emissions from complete wall build-ups as they can be used for internal Partition walls and the internal insulation of external walls. Test chambers were designed, allowing the compounds to release only from the surface of the material facing indoors under testing Parameters that were chosen to simulate model room conditions. The emission test results were evaluated using the AgBB evaluation scheme, a procedure for the health-related evaluation of construction products and currently applied for the approval of specific groups of building materials in Germany. Seventeen out of 19 sample build-ups tested in this study would have passed this scheme since they generally proved to be low-emitting and although the combined emissions of multiple materials were tested, 50% of the measurements could be terminated before half of the total testing time. KW - Bio-based insulation KW - Earthen building materials KW - Volatile organic compounds KW - Semivolatile organic compounds KW - Radon PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519634 DO - https://doi.org/10.3390/ma14010234 VL - 14 IS - 1 (Special issue: Measurement of the environmental impact of materials) SP - 234-1 EP - 234-14 PB - MDPI CY - Basel AN - OPUS4-51963 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liaskos, C. A1 - Rhoderick, G. A1 - Hodges, J. A1 - Possolo, A. A1 - Wilke, Olaf T1 - Pilot comparison CCQM-P177 - monoterpenes in nitrogen at 2.5 nmol/mol - final report JF - Metrologia N2 - Growing awareness of the impact of monoterpenes on climate, atmospheric chemistry, and indoor air quality has necessitated the development of measurement standards to globally monitor and control their emissions. For National Metrology Institutes to develop such standards, it is essential that they demonstrate measurement equivalence for assigned values at the highest levels of accuracy. This report describes the results of a pilot comparison for 4 key monoterpene species: α-pinene, 3-carene, R-limonene and 1,8-cineole, at a nominal amount-of-substance fraction of 2.5 nmol mol-1. The objective of this comparison is to evaluate participant capabilities to measure trace-level monoterpenes using their own calibration techniques. KW - Pilot comparison KW - CCQM KW - Monoterpene KW - Accuracy PY - 2020 DO - https://doi.org/10.1088/0026-1394/57/1A/08018 SN - 0026-1394 SN - 1681-7575 VL - 57 IS - 1A SP - 08018-1 EP - 08018-21 PB - IOP Science AN - OPUS4-51111 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Even, Morgane A1 - Hutzler, C. A1 - Wilke, Olaf A1 - Luch, A. T1 - Emissions of volatile organic compounds from polymer-based consumer products: comparison of three emission chamber sizes JF - Indoor Air N2 - The ISO 16000 standard series provide guidelines for emission measurements of volatile organic compounds (VOCs) from building materials. However, polymer-based consumer products such as toys may also release harmful substances into indoor air. In such cases, the existing standard procedures are unsuitable for official control laboratories due to high costs for large emission testing chambers. This paper aims at developing and comparing alternative and more competitive methods for the emission testing of consumer products. The influence of the emission chamber size was investigated as smaller chambers are more suited to the common size of consumer products and may help to reduce the costs of testing. Comparison of the performance of a 203 l emission test chamber with two smaller chambers with the capacity of 24 l and 44 ml, respectively, was carried out by using a polyurethane reference material spiked with 14 VOCs during the course of 28 days. The area-specific emission rates obtained in the small chambers were always similar to those of the 203 l reference chamber after a few hours. This implies that smaller chambers can provide at least useful numbers on the extent of polymer-based consumer product emissions into indoor air, thereby supporting meaningful exposure assessments. KW - Comparison KW - Consumer products KW - Emission chamber KW - Reference material KW - Volatile organic compounds PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-493697 DO - https://doi.org/10.1111/ina.12605 VL - 30 IS - 1 SP - 40 EP - 48 PB - Wiley VCH-Verlag AN - OPUS4-49369 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wilke, Olaf A1 - Jann, Oliver A1 - Plehn, W. A1 - Brozowski, F. T1 - Untersuchungen zur Etablierung der DIN EN 16516 als neuer Referenznorm für die Prüfung von Formaldehydemissionen aus Holzwerkstoffen gemäß Chemikalien-Verbotsverordnung T1 - Investigations to establish DIN EN 16516 as new reference standard for testing of formaldehyde emissions from wood-based panels under the Chemikalien-Verbotsverordnung JF - Gefahrstoffe Reinhaltung der Luft N2 - Im Januar 2018 wurde die DIN EN 16516 „Bauprodukte: Bewertung der Freisetzung gefährlicher Stoffe – Bestimmung von Emissionen in die Innenraumluft“ als harmonisierte europäische Prüfnorm veröffentlicht. Für die Etablierung der DIN EN 16516 als neue Referenznorm wurden verschiedene Emissionsprüfungen mit dem Ziel durchgeführt, ein neues Prüfverfahren für Formaldehydemissionen aus Holzwerkstoffen zu erarbeiten. Das übergeordnete Ziel ist die Minimierung des Risikos von Überschreitungen des Innenraumrichtwertes für Formaldehyd. Die Untersuchungen ergaben teilweise hohe Formaldehydemissionen, insbesondere bei höheren Beladungsfaktoren und Temperaturen, sowie bei niedrigen Luftwechselraten. Eine getestete Spanplatte hätte aufgrund ihrer hohen Formaldehydemission nicht auf den deutschen Markt gebracht werden dürfen. Durch vergleichende Untersuchungen konnte ein Umrechnungsfaktor in Höhe von 2,0 für die Umrechnung von Prüfwerten nach DIN EN 717-1 zu DIN EN 16516 abgeleitet werden. N2 - DIN EN 16516 "Construction products: Assessment of release of dangerous substances - Determination of emissions into indoor air" was published as a harmonized European standard in January 2018. For the establishment of DIN EN 16516 as the new reference standard various emission tests were carried out with the aim to develop a new test procedure for the measurement of formaldehyde emissions from wood-based panels. The superior aim is to minimize the risk of exceeding the indoor air reference value for formaldehyde. The investigations showed some particularly high formaldehyde emissions, especially at higher loading and temperature and at low air change rates. One of the tested particle boards exceeded the formaldehyde limit value and should not have been sold in Germany. For the conversion of test values from DIN EN 717-1 to DIN EN 16516 a conversion factor of 2.0 was derived from the comparative investigations. KW - Formaldehyd KW - DIN EN 16516 KW - Innenraumluft KW - Emissionsprüfung PY - 2019 SN - 0949-8036 VL - 79 IS - 3 SP - 79 EP - 85 PB - VDI Fachmedien CY - Düsseldorf AN - OPUS4-47666 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steger, S. A1 - Horn, Wolfgang A1 - Eggert, G. A1 - Krekel, C. T1 - Are cellulose ethers safe for the conservation of artwork? New insights in their VOC activity by means of Oddy testing JF - Heritage Science N2 - Cellulose ethers, like methyl cellulose (MC) or hydroxypropyl cellulose (HPC), are widely used in conservation. They also occur as additives and rheology modifiers in various products like dispersions or gels. Do such products release harmful volatile organic compounds (VOC) during their accelerated aging? A mass testing series utilizing the Oddy test of 60 commercial cellulose ethers ranks the products in safe for permanent use (P, no corrosion), only for temporary use (T, slight corrosion), and unsuitable at all (F, heavy corrosion). Results show that 55% of the products passed the test whereas 33% are for temporary use as slight corrosion occurred on at least one metal coupon and only 11% failed the Oddy test. Raman measurements of the corrosion products identified oxides like massicot, litharge, cuprite, and tenorite among carbonates (hydrocerussite, plumbonacrite), and acetates like basic lead acetate, lead acetate trihydrate as well as lead formate as main phases. For example, commercial, industrial Klucel® G (HPC) scored a T rating through slight corrosion on the lead coupon. Basic lead acetate among other phases indicates the presence of acetic acid. Additional measurements of the sample with thermal desorption GC–MS utilizing the BEMMA scheme confirm the high acetic acid outgassing and reveal the presence of a small amount of formaldehyde. KW - Cellulose ether KW - Corrosion KW - Oddy test KW - VOC KW - BEMMA PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547591 DO - https://doi.org/10.1186/s40494-022-00688-4 SN - 2050-7445 VL - 10 IS - 1 SP - 1 EP - 12 PB - Springer Open AN - OPUS4-54759 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Karafiludis, Stephanos A1 - Bhattacharya, Biswajit A1 - de Oliveira Guilherme Buzanich, Ana A1 - Fink, Friedrich A1 - Feldmann, Ines A1 - ten Elshof, J. E. A1 - Emmerling, Franziska A1 - Stawski, Tomasz T1 - Thermally processed Ni-and Co-struvites as functional materials for proton conductivity JF - Dalton Transactions N2 - We present how mesoporosity can be engineered in transition metal phosphate (TMPs) materials in a template-free manner. The method involves the transformation of a precursor metal phosphate phase, called M-struvite (NH4MPO4·6H2O, M = Mg2+, Ni2+, Co2+, NixCo1−x2+). It relies on the thermal decomposition of crystalline M-struvite precursors to an amorphous and simultaneously mesoporous phase, which forms during degassing of NH3 and H2O. The temporal evolution of mesoporous frameworks and the response of the metal coordination environment were followed by in situ and ex situ scattering and diffraction, as well as X-ray spectroscopy. Despite sharing the same precursor struvite structure, different amorphous and mesoporous structures were obtained depending on the involved transition metal. We highlight the systematic differences in absolute surface area, pore shape, pore size, and phase transitions depending on the metal cation present in the analogous M-struvites. The amorphous structures of thermally decomposed Mg-, Ni- and NixCo1−x-struvites exhibit high surface areas and pore volumes (240 m2 g−1 and 0.32 cm−3 g−1 for Mg and 90 m2 g−1 and 0.13 cm−3 g−1 for Ni). We propose that the low-cost, environmentally friendly M-struvites could be obtained as recycling products from industrial and agricultural wastewaters. These waste products could be then upcycled into mesoporous TMPs through a simple thermal treatment for further application, for instance in (electro)catalysis. KW - Struvite KW - Phosphates KW - Transition metals KW - Proton conductivity PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575862 DO - https://doi.org/10.1039/D3DT00839H SN - 1477-9226 SP - 1 EP - 13 PB - Royal Society of Chemisty (RSC) CY - London/Cambridge AN - OPUS4-57586 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mrkwitschka, Paul A1 - Rühle, Bastian A1 - Kuchenbecker, Petra A1 - Löhmann, Oliver A1 - Lindemann, Franziska A1 - Hodoroaba, Vasile-Dan T1 - Embedding and cross-sectioning as a sample preparation procedure for accurate and representative size and shape measurement of nanopowders JF - Scientific Reports N2 - Reliable measurement of the size of polydisperse, complex-shaped commercial nanopowders is a difficult but necessary task, e.g., for regulatory requirements and toxicity risk assessment. Suitable methods exist for the accurate characterization of the size of non-aggregated, stabilized, spherical and monodisperse nanoparticles. In contrast, industrial nanoscale powders usually require dedicated sample preparation procedures developed for the analysis method of choice. These nano-powders tend to agglomerate and/or aggregate, a behavior which in combination with an innate broad particle size distribution and irregular shape often significantly alters the achievable accuracy of the measured size parameters. The present study systematically tests two commercially available nanoscale powders using different sample preparation methods for correlative analysis by scanning electron microscopy, dynamic light scattering, Brunauer–Emmet–Teller method and differential mobility analysis. One focus was set on the sample preparation by embedding nanoparticles in carbon-based hot-mounting resin. Literature on this topic is scarce and the accuracy of the data extracted from cross sections of these particles is unclearly stated. In this paper systematic simulations on the deviation of the size parameters of well-defined series of nanoparticles with different shapes from the nominal value were carried out and the contributing factors are discussed. KW - Nanopowder KW - Electron microscopy KW - Sample preparation KW - Cross-sectioning KW - Cerium oxide KW - Zinc oxide PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593289 DO - https://doi.org/10.1038/s41598-023-51094-0 SN - 2045-2322 VL - 14 SP - 1 EP - 10 PB - Springer Nature CY - London AN - OPUS4-59328 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herbig, B. A1 - Jörres, R. A. A1 - Schierl, R. A1 - Simon, M. A1 - Langner, Jeanette A1 - Seeger, Stefan A1 - Nowak, D. A1 - Karrasch, S. T1 - Psychological and cognitive effects of laser printer emissions: A controlled exposure study JF - Indoor Air N2 - The possible impact of ultrafine particles from laser printers on human health is controversially discussed although there are persons reporting substantial symptoms in relation to these emissions. A randomized, single-blinded, cross-over experimental design with two exposure conditions (high-level and low-level exposure) was conducted with 23 healthy subjects, 14 subjects with mild asthma, and 15 persons reporting symptoms associated with laser printer emissions. To separate physiological and psychological effects, a secondary physiologically based categorization of susceptibility to particle effects was used. In line with results from physiological and biochemical assessments, we found no coherent, differential, or clinically relevant effects of different exposure conditions on subjective complaints and cognitive performance in terms of attention, short-term memory, and psychomotor performance. However, results regarding the psychological characteristics of participants and their situational perception confirm differences between the participants groups: Subjects reporting symptoms associated with laser printer emissions showed a higher psychological susceptibility for adverse reactions in line with previous results on persons with multiple chemical sensitivity or idiopathic environmental intolerance. In conclusion, acute psychological and cognitive effects of laser printer emissions were small and could be attributed only to different participant groups but not to differences in exposure conditions in terms of particle number concentrations. KW - Cognitive performance KW - Exposure KW - Idiopathic environmental intolerance KW - Laser printer emission KW - Multiple chemical sensitivity KW - Subjective complaints PY - 2018 DO - https://doi.org/10.1111/ina.12429 SN - 1600-0668 SN - 0905-6947 VL - 28 IS - 1 SP - 112 EP - 124 PB - John Wiley & Sons, Inc. CY - 111 RIVER ST, HOBOKEN 07030-5774, NJ USA AN - OPUS4-43945 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Even, Morgane A1 - Wilke, Olaf A1 - Kalus, Sabine A1 - Schultes, P. A1 - Hutzler, C. A1 - Luch, A. T1 - Formaldehyde emissions from wooden toys: Comparison of different measurement methods and assessment of exposure JF - Materials N2 - Formaldehyde is considered as carcinogenic and is emitted from particleboards and plywood used in toy manufacturing. Currently, the flask method is frequently used in Europe for market surveillance purposes to assess formaldehyde release from toys, but its concordance to Levels measured in emission test chambers is poor. Surveillance laboratories are unable to afford laborious and expensive emission chamber testing to comply with a new amendment of the European Toy Directive; they need an alternative method that can provide reliable results. Therefore, the application of miniaturised emission test chambers was tested. Comparisons between a 1 m3 emission test chamber and 44 mL microchambers with two particleboards over 28 days and between a 24 L desiccator chamber and the microchambers with three puzzle samples over 10 days resulted in a correlation coefficient r2 of 0.834 for formaldehyde at steady state. The correlation between the results obtained in microchambers vs. flask showed a high variability over 10 samples (r2: 0.145), thereby demonstrating the error-proneness of the flask method in comparison to methods carried out under ambient parameters. An exposure assessment was also performed for three toy puzzles: indoor formaldehyde concentrations caused by puzzles were not negligible (up to 8 µg/m3), especially when more conservative exposure scenarios were considered. KW - EN 717-3 KW - Formaldehyde KW - Wooden toys KW - Emission test chamber KW - Flask method KW - Microchamber PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520196 DO - https://doi.org/10.3390/ma14020262 VL - 14 IS - 2 (Special issue: Measurement of the environmental impact of materials) SP - 262-1 EP - 262-16 PB - MDPI AN - OPUS4-52019 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wilke, Olaf A1 - Horn, Wolfgang A1 - Richter, Matthias A1 - Jann, Oliver T1 - Volatile organic compounds from building products - Results from six round robin tests with emission test chambers conducted between 2008 and 2018 JF - Indoor Air N2 - Emission testing of volatile organic compounds (VOC) from materials and products is commonly based on emission test chamber measurements. To ensure the comparability of results from different testing laboratories, their measurement performance must be verified. For this purpose, Bundesanstalt für Materialforschung und -prüfung (BAM) organizes an international proficiency test (round robin test, RRT) every two years using well-characterized test materials (one sealant, one furniture board, and four times a lacquer) with defined VOC emissions. The materials fulfilled the requirements of homogeneity, reproducibility, and stability. Altogether, 36 VOCs were included of which 33 gave test chamber air concentrations between 13 and 83 µg/m3. This is the typical concentration range to be expected and to be quantified when performing chamber tests. Three compounds had higher concentrations between 326 and 1105 µg/m3. In this paper, the relative standard deviations (RSD) of BAM round robin tests since 2008 are compared and the improvement of the comparability of the emission chamber testing is shown by the decrease of the mean RSD down to 28 % in 2018. In contrast, the first large European interlaboratory comparison in 1999 showed a mean RSD of 51 %. KW - Construction product KW - Emission test chamber KW - Interlaboratory comparison KW - Proficiency testing KW - Rround robin test KW - VOC emission PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-526139 DO - https://doi.org/10.1111/ina.12848 VL - 31 IS - 6 SP - 2049 EP - 2057 PB - Wiley AN - OPUS4-52613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brandt, S. A1 - Müller, B. A1 - Brozowski, F. A1 - Plehn, W. A1 - Horn, Wolfgang T1 - Weiterentwicklung des Geruchsmessverfahrens für Bauprodukte T1 - Further development of the odour measurement method for building products JF - Gefahrstoffe, Reinhaltung der Luft = Air quality control N2 - Bauprodukte und Einrichtungsgegenstände für Innenräume, wie Bodenbeläge und Wandpaneele, sollen das Wohlbefinden und die Gesundheit der Raumnutzerinnen und -nutzer nicht durch das Ausdünsten von Geruchsstoffen stören. Mit der Geruchsprüfung nach ISO 16000-28 „Innenraumluft - Bestimmung der Geruchsstoffemissionen aus Bauprodukten mit einer Emissionsprüfkammer“ wird der Produktgeruch zu einer messbaren Größe. So kann z. B. die empfundene Intensität, also die Stärke eines Geruchseindruckes, mit Hilfe eines Vergleichsmaßstabes von Probandinnen und Probanden ermittelt werden. Im hier vorgestellten Projekt werden Vorschläge zur Weiterentwicklung der Methode vorgestellt, um im Ergebnis die Reproduzierbarkeit der Messergebnisse weiter zu verbessern. Dabei werden vor allem das Probenpräsentationssystem und die Bewertungsmethodik für die empfundene Intensität bei der Bewertung von Bauprodukten gemäß AgBB-Schema betrachtet, da diese einen wesentlichen Einfluss haben. N2 - Emissions or odours occurring from building products and furnishings for interiors, like floor coverings or wall panels, should not have a negative impact on well-being or health. Odours can be measured applying the standard ISO 16000-28 „Indoor air - Determination of odour emissions from building products using test chambers” It describes among other procedures the assessment of perceived intensi-ty with comparative scale by a group of panellists. In the study presented here, proposals for further technical development of the methodology are discussed to increase the reproducibility of measurement results. The sampling procedure and evaluation method of perceived intensity are investigated in particular because they have a major influence at the assessment of construction products applying the procedure of the Committee for Health Evaluation of Building Products. KW - Geruchsmessung KW - Emissionen KW - Bauprodukte KW - VOC PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527458 UR - http://www.gefahrstoffe.de SN - 0949-8036 SN - 1436-4891 VL - 81 IS - 3-4 SP - 151 EP - 155 PB - VDI Fachmedien CY - Düsseldorf AN - OPUS4-52745 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seeger, Stefan A1 - Osan, J. A1 - Czömpöly, O. A1 - Gross, A. A1 - Stosnach, H. A1 - Stabile, L. A1 - Ochsenkuehn-Petropoulou, M. A1 - Tsakanika, L. A1 - Lymperopoulou, T. A1 - Goddard, S. A1 - Fiebig, M. A1 - Gaie-Levrel, F. A1 - Kayser, Y. A1 - Beckhoff, B. T1 - Quantification of Element Mass Concentrations in Ambient Aerosols by Combination of Cascade Impactor Sampling and Mobile Total Reflection X-ray Fluorescence Spectroscopy JF - Atmosphere N2 - Quantitative chemical analysis of airborne particulate matter (PM) is vital for the understanding of health effects in indoor and outdoor environments, as well as for enforcing EU air quality regulations. Typically, airborne particles are sampled over long time periods on filters, followed by lab-based analysis, e.g., with inductively coupled plasma mass spectrometry (ICP-MS). During the EURAMET EMPIR AEROMET project, cascade impactor aerosol sampling is combined for the first time with on-site total reflection X-ray fluorescence (TXRF) spectroscopy to develop a tool for quantifying particle element compositions within short time intervals and even on-site. This makes variations of aerosol chemistry observable with time resolution only a few hours and with good size resolution in the PM10 range. The study investigates the proof of principles of this methodological approach. Acrylic discs and silicon wafers are shown to be suitable impactor carriers with sufficiently smooth and clean surfaces, and a non-destructive elemental mass concentration measurement with a lower limit of detection around 10 pg/m3 could be achieved. We demonstrate the traceability of field TXRF measurements to a radiometrically calibrated TXRF reference, and the results from both analytical methods correspond satisfactorily. KW - TXRF KW - Reference method KW - Cascade impactor KW - Ambient aerosols KW - Particles KW - Air quality monitoring KW - Element mass concentration KW - Size resolved chemical composition KW - Time resolved chemical composition KW - ICP-MS PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521860 UR - http://www.aerometproject.com/ DO - https://doi.org/10.3390/atmos12030309 SN - 2073-4433 VL - 12 IS - 3 SP - 309 EP - 337 PB - MDPI CY - Basel, Schweiz AN - OPUS4-52186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Horender, S. A1 - Auderset, K. A1 - Quincey, P. A1 - Seeger, Stefan A1 - Skov, S. N. A1 - Dierschel, K. A1 - Smith, T. O.M. A1 - Williams, K. A1 - Aegerter, C. C. A1 - Kalbermatter, D. M. A1 - Gaie-Levrel, F. A1 - Vasilatou, K. T1 - Facility for production of ambient-like model aerosols (PALMA) inthe laboratory: application in the intercomparison of automated PMmonitors with the reference gravimetric method JF - Atmospheric Measurement Techniques N2 - A new facility has been developed which allows for a stable and reproducible production of ambient-like model aerosols (PALMA) in the laboratory. The set-up consists of multiple aerosol generators, a custom-made flow tube homogeniser, isokinetic sampling probes, and a system to control aerosol temperature and humidity. Model aerosols containing elemental carbon, secondary organic matter from the ozonolysis of α-pinene, inorganic salts such as ammonium sulfate and ammonium nitrate, mineral dust particles,and water were generated under different environmental conditions and at different number and mass concentrations. The aerosol physical and chemical properties were characterised with an array of experimental methods, including scanning mobility particle sizing, ion chromatography, total reflection X-ray fluorescence spectroscopy and thermo-optical analysis. The facility is very versatile and can find applications in the calibration and performance characterisation of aerosol instruments monitoring ambient air. In this study, we performed, as proof of concept, an intercomparison of three different commercial PM (particulate matter) monitors (TEOM1405, DustTrak DRX 8533 and Fidas Frog) with the gravimetric reference method under three simulated environmental scenarios. The results are presented and compared to previous field studies. We believe that the laboratory-based method for simulating ambient aerosols presented here could provide in the future a useful alternative to time-consuming and expensive field campaigns, which are often required for instrument certification and calibration. KW - Model aerosols KW - Intercomparison KW - PM monitors KW - Aerosol gravimetry PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521342 DO - https://doi.org/10.5194/amt-14-1225-2021 VL - 14 IS - 2 SP - 1225 EP - 1238 PB - Copernicus Publications AN - OPUS4-52134 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tang, Chi-Long A1 - Seeger, Stefan T1 - Systematic ranking of filaments regarding their particulate emissions during fused filament fabrication 3D printing by means of a proposed standard test method JF - Indoor Air N2 - The diversity of fused filament fabrication (FFF) filaments continues to grow rapidly as the popularity of FFF-3D desktop printers for the use as home fabrication devices has been greatly increased in the past decade. Potential harmful emissions and associated health risks when operating indoors have induced many emission studies. However, the lack of standardization of measurements impeded an objectifiable comparison of research findings. Therefore, we designed a chamber-based standard method, i.e., the strand printing method (SPM), which provides a standardized printing procedure and quantifies systematically the particle emission released from individual FFF-3D filaments under controlled conditions. Forty-four marketable filament products were tested. The total number of emitted particles (TP) varied by approximately four orders of magnitude (1E9 ≤ TP ≤ 1E13), indicating that origin of polymers, manufacturer-specific additives, and undeclared impurities have a strong influence. Our results suggest that TP characterizes an individual filament product and particle emissions cannot be categorized by the polymer type (e.g., PLA or ABS) alone. The user's choice of a filament product is therefore decisive for the exposure to released particles during operation. Thus, choosing a filament product awarded for low emissions seems to be an easily achievable preemptive measure to prevent health hazards. KW - Emission test method KW - FFF-printing KW - Particle emission KW - Indoor air quality KW - FFF-filament PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545087 DO - https://doi.org/https://doi.org/10.1111/ina.13010 SN - 1600-0668 VL - 32 IS - 3 SP - 1 EP - 12 PB - Wiley CY - Hoboken, New Jersey, USA AN - OPUS4-54508 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bucar, K. A1 - Malet, J. A1 - Stabile, L. A1 - Pražnikar, J. A1 - Seeger, Stefan A1 - Žitnik, M. T1 - Statistics of a Sharp GP2Y Low-Cost Aerosol PM Sensor Output Signals JF - Sensors N2 - In this work, we characterise the performance of a Sharp optical aerosol sensor model GP2Y1010AU0F. The sensor was exposed to different environments: to a clean room, to a controlled atmosphere with known aerosol size distribution and to the ambient atmosphere on a busy city street. During the exposure, the output waveforms of the sensor pulses were digitised, saved and a following offline analysis enabled us to study the behaviour of the sensor pulse-by-pulse. A linear response of the sensor on number concentration of the monosized dispersed PSL particles was shown together with an almost linear dependence on particle diameters in the 0.4 to 4 micrometer range. The gathered data about the sensor were used to predict its response to an ambient atmosphere, which was observed simultaneously with a calibrated optical particle counter. KW - Aerosol KW - Partikel KW - Aerosolsensor KW - Luftgüte KW - Umweltmessung PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517466 DO - https://doi.org/10.3390/s20236707 SN - 1424-8220 VL - 20 IS - 23 SP - 6707 PB - MDPI CY - Basel, Schweiz AN - OPUS4-51746 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ahlawat, A. A1 - Seeger, Stefan A1 - Gottschalk, Martin A1 - Tuch, T. A1 - Wiedensohler, A. T1 - Observation of systematic deviations between Faraday cup aerosol electrometers for varying particle sizes and flow rates - results of the AEROMET FCAE workshop JF - Metrologia N2 - Condensation particle counters (CPCs) are widely used for the measurement of aerosol particle number concentrations in the size range from approximately 3 nm to 3 μm. For an SI-traceable calibration of the size-dependent counting efficiency, which is advisable on a regular basis and required in several applications, Faraday cup aerosol electrometers (FCAEs) are considered to be a suitable SI-traceable reference.While the volumetric aerosol inlet flowrate and the electrical current measurement in FCAEs can be related to respective SI references, inter-comparison exercises for FCAEs are still performed on a regular basis to establish reliable uncertainty budgets and to further investigate the influences of designs and operational parameters on comparability. This is strongly demanded in the international community of metrological institutes and aerosol calibration facilities around the world, which provide CPC calibrations. In the present study, the performance of FCAEs was investigated,using Ag test aerosol particles with a 30 nm particle diameter by varying the inlet flowrates from 0.5 l min−1 to 4 l min−1. From our experimental results, significant deviations were observed in FCAE currents at sample flowrates smaller than 1.5 l min−1. It is recommended that these discrepancies should be quantified before an FCAE is used for CPC calibration at low sample flowrates and small particle sizes in the sub-30 nm size range. KW - Faraday cup aerosol electrometer KW - CPC calibration KW - Inter-comparison KW - Aerosol measurement instruments PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-531315 DO - https://doi.org/10.1088/1681-7575/ac0710 SN - 1681-7575 SN - 0026-1394 VL - 58 IS - 5 SP - 1 EP - 8 PB - Institute of Physics (IOP) CY - Bristol, UK AN - OPUS4-53131 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vigna, L. A1 - Gottschalk, Martin A1 - Cacocciola, N. A1 - Verna, A. A1 - Marasso, S. L. A1 - Seeger, Stefan A1 - Pirri, C.F. A1 - Cocuzza, M. T1 - Flexible and reusable parylene C mask technology for applications in cascade impactor air quality monitoring systems JF - Micro and Nano Engineering N2 - The development of traceable new methodologies to quantify elemental air pollutants in particulate matter (PM) supports modernization of methods used in air quality monitoring networks in Europe. In the framework of the EURAMET EMPIR AEROMET II project, the combination of cascade impactor aerosol sampling and total reflection X-ray fluorescence elemental spectroscopy (TXRF) was investigated. This technique requires a traceable calibration based on reference samples. This paper describes a new, simple and effective method to produce such reference samples using flexible, reusable, and low-cost parylene C shadow masks, fabricated by photolithographic steps. These shadow masks can be used to produce reference samples that mimic the Dekati cascade impactor’s deposition patterns by applying as-prepared micro stencils to 30 mm acrylic substrates and evaporating a reference material (Ti) in arrangements of thin circular dots. The highly flexible direct patterning of acrylic discs with reference material, otherwise impossible with conventional photolithography, allows multiple reusing of the same micro stencils. The aspect ratios of the dots could be repeated with an error less than 4 %. A first set of standard reference samples for the 13 stages of the Dekati cascade impactor was produced and preliminary TXRF measurements of the deposited Ti masses were performed. The centricity of the deposition patterns turned out to be an important parameter for the quality of the TXRF results. The parylene mask technology for the production of reference samples turns out to be a promising new approach for the traceable calibration of TXRF spectrometers for the quantification of element concentrations in environmental aerosol samples but, due to its great versatility, it could be used for several other micropatterning applications on conventional and unconventional substrates. KW - AEROMET II KW - Aerosol KW - Parylene C KW - Reference samples KW - Flexible shadow masks KW - Cascade impactor KW - Air quality monitoring KW - Micropatterning KW - Mask fabrication KW - Elemental aerosol analysis KW - TXRF PY - 2022 DO - https://doi.org/10.1016/j.mne.2022.100108 SN - 2590-0072 VL - 14 SP - 1 EP - 19 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-54252 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Beyer, Sebastian A1 - Schürmann, Robin A1 - Feldmann, Ines A1 - Blocki, A. A1 - Bald, Ilko A1 - Schneider, Rudolf A1 - Emmerling, Franziska T1 - Maintaining Stable Zeolitic Imidazolate Framework (ZIF) Templates during Polyelectrolyte Multilayer Coating JF - Colloid and Interface Science Communications N2 - Equipping ZIF particles with a polyelectrolyte membrane provides functional groups at their interface, enabling further conjugations necessary for applications such as targeted drug delivery. Previous approaches to coat ZIF particles with polyelectrolytes led to surface corrosion of the template material. This work overcomes previous limitations by performing a Layer-by-Layer (LbL) polyelectrolyte coating onto ZIF-8 and ZIF-67 particles in nonaqueous environment. Using the 2-methylimidazolium salt of polystyrensulfonic acid instead of the acid itself and polyethyleneimine in methanol led to intact ZIF particles after polyelectrolyte coating. This was verified by electron microscopy. Further, zetapotential and atomic force microscopy measurements confirmed a continuous polyelectrolyte multilayer built up. The here reported adaption to the well-studied (LbL) polyelectrolyte selfassembly process provides a facile method to equip ZIF particles with a nanometer thin polyelectrolyte multilayer membrane. KW - Zeolithe KW - Molecular Organic Frameworks KW - MOF KW - ZIF KW - Layer-by-Layer KW - Beschichtung KW - Polyelektrolyt PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-447729 DO - https://doi.org/10.1016/j.colcom.2017.11.004 SN - 2215-0382 VL - 22 SP - 14 EP - 17 PB - Elsevier B.V. CY - Amsterdam, NL AN - OPUS4-44772 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gerrits, Ruben A1 - Pokharel, R. A1 - Breitenbach, Romy A1 - Radnik, Jörg A1 - Feldmann, Ines A1 - Schuessler, J.A. A1 - von Blanckenburg, F. A1 - Gorbushina, Anna A1 - Schott, J. T1 - How the rock-inhabiting fungus K. petricola A95 enhances olivine dissolution through attachment JF - Geochimica et Cosmochimica Acta N2 - Free-living and mycorrhizal fungi are able to enhance the weathering of rock and other solid substrates. Deciphering the exact mechanisms of these natural processes requires their experimental simulation. Moreover, by performing these simulations with genetically amenable rock-weathering fungi, one can knock-out certain fungal traits and consequently identify their weathering-relevant function. Here, the effect of the rock-inhabiting fungus, Knufia petricola A95, on the dissolution kinetics of an Fe-bearing olivine (Mg1.86Fe0.19SiO4) is investigated at 25 °C and pH 6 using reproducible batch and mixed flow experiments. The availability of a melanin-deficient mutant (ΔKppks) of K. petricola A95, which produces more extracellular polymeric substances (EPS) than the wild type (WT), enables the comparative study of the role of melanin and EPS in olivine dissolution. In abiotic dissolution experiments, the olivine dissolution rate decreased considerably over time at pH 6 but not at pH 3.5. This inhibition of abiotic olivine dissolution at pH 6 was most likely caused by the in-situ oxidation of ferrous Fe and/or the precipitation of ferric hydroxides at the olivine surface. In corresponding biotic experiments at pH 6, both the wild type K. petricola and its melanin-deficient mutant ΔKppks solubilised and bound significant amounts of Fe released by olivine dissolution. Fe oxidation and precipitation were thus prevented and olivine dissolution proceeded faster than in the abiotic experiments. By sequestering Fe directly at the olivine surface, the attached wild type K. petricola cells were particularly efficient at preventing the oxidation of Fe at the mineral surface: the slowdown of olivine dissolution almost completely disappeared. The attachment capacity of these wild type cells is most likely mediated by wild type-specific EPS. Our presented experimental systems allow the oxidation of mineral-released Fe and include a rock-inhabiting fungus, thus simulating chemical, physical and biological conditions that set dissolution rates in a way that is relevant to natural ecosystems. KW - Black fungi KW - Bio-weathering KW - Forsterite KW - Knock-out mutant KW - Extracellular polymeric substances KW - Melanin Adhesion PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509332 DO - https://doi.org/10.1016/j.gca.2020.05.010 VL - 282 SP - 76 EP - 97 PB - Elsevier Ltd. AN - OPUS4-50933 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kayser, Y. A1 - Gross, A. A1 - Hönicke, P. A1 - Osan, J. A1 - Pollakowski-Herrmann, B. A1 - Seeger, Stefan A1 - Beckhoff, B. T1 - Reliable chemical analysis of aerosols by reference-free X-ray spectrometry for monitoring airborne particulate matter JF - Spectroscopy N2 - The physical and chemical analysis of aerosols using reliable and physically traceable methods is important for the thorough investigation of airborne particles to support a better understanding of their origin as well as their health and climate impacts. Within the European Metrology Research AeroMet project,the aim of hysikalisch–Technische Bundesanstalt’s (PTB) X-ray spectrometry group is to develop and establish traceable and reliable X-ray methods to measure the elemental mass deposition per unit area, the elemental composition,and the chemical binding state of particulate matter supported by a flat substrate. This approach can substantially contribute to support quantitative analytical methods during on-site measurement campaigns where portable Instrumentation is employed by qualifying suitable calibration samples for commercial analytical X-ray instruments and by investigating samples collected during the field campaign. KW - AEROMET project KW - X-Ray analysis KW - TXRF KW - Aerosols KW - Particles KW - Air pollution KW - Elemental composition PY - 2020 UR - https://www.spectroscopyonline.com/view/reliable-chemical-analysis-of-aerosols-by-reference-free-x-ray-spectrometry-for-monitoring-airborne-particulate-matter SN - 0887-6703 VL - 35 IS - 10 SP - 42 EP - 46 PB - MJH Life Sciences CY - Cranbury, NJ AN - OPUS4-53357 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völzke, Jule L. A1 - Hodjat Shamami, Parya A1 - Gawlitza, Kornelia A1 - Feldmann, Ines A1 - Zimathies, Annett A1 - Meyer, Klas A1 - Weller, Michael G. T1 - High-Purity Corundum as Support for Affinity Extractions from Complex Samples JF - Separations N2 - Nonporous corundum powder, known as an abrasive material in the industry, was functionalized covalently with protein binders to isolate and enrich specific proteins from complex matrices. The materials based on corundum were characterized by TEM, ESEM, BET, DLS, EDS, and zeta potential measurements. The strong Al-O-P bonds between the corundum surface and amino phosphonic acids were used to introduce functional groups for further conjugations. The common crosslinker glutaraldehyde was compared with a hyperbranched polyglycerol (PG) of around 10 kDa. The latter was oxidized with periodate to generate aldehyde groups that can covalently react with the amines of the surface and the amino groups from the protein via a reductive amination process. The amount of bound protein was quantified via aromatic amino acid analysis (AAAA). This work shows that oxidized polyglycerol can be used as an alternative to glutaraldehyde. With polyglycerol, more of the model protein bovine serum albumin (BSA) could be attached to the surface under the same conditions, and lower non-specific binding (NSB) was observed. As a proof of concept, IgG was extracted with protein A from crude human plasma. The purity of the product was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). A binding capacity of 1.8 mg IgG per gram of corundum powder was achieved. The advantages of corundum include the very low price, extremely high physical and chemical stability, pressure resistance, favorable binding kinetics, convenient handling, and flexible application. KW - Corundum KW - Sapphire KW - Affinity chromatography KW - Antibodies KW - Self-assembled monolayers (SAM) KW - Polyglycerol KW - Dendrimer KW - Nonspecific binding (NSB) KW - Purification KW - Solid-phase extraction (SPE) PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559342 DO - https://doi.org/10.3390/separations9090252 VL - 9 IS - 9 SP - 1 EP - 13 PB - MDPI CY - Basel AN - OPUS4-55934 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seeger, Stefan A1 - Brödner, Doris A1 - Jacobi, T. A1 - Rasch, Fabian A1 - Rothhardt, Monika A1 - Wilke, Olaf T1 - Emissions of fine and ultrafine particles and volatile organic compounds from different filament materials operated on a low-cost 3D printer T1 - Emissionen feiner und ultrafeiner Partikel sowie flüchtiger organischer Verbindungen beim Einsatz verschiedener Filamentmaterialien in einem „low-cost“-3D-Drucker JF - Gefahrstoffe - Reinhaltung der Luft N2 - 3D-printing or additive manufacturing has many promising and unique advantages. Especially low cost molten polymer Deposition Printers are increasingly populär in the private and educational sector. Their environmental friendliness can be questioned due to recently reported ultrafine particle and suspected VOC emissions, To further investigate 3D-printing as a potential indoor air pollution source we characterized fine and ultrafine particle emissions from a molten polymer deposition printer producing a 3D object with ten marketable polymer filament materials under controlled conditions in a test chamber. VOC emissions from the filaments have also been compared. Using a straightforward emission model time dependent and averaged particle emission rates were determined. The results indicate that under comparable conditions some filament materials produce mainly ultrafine particles up to an average rate of 1013 per minute. This value is in the upper ränge of typical indoor ultrafine particle sources (e.g. Smoking, frying, candle light, laser printer). The observed material-specific rates differ by five Orders of magnitude. Filament-specific gaseous emissions of organic compounds such as bisphenol A, styrene and others were also detected. Our results suggest a detailed evaluation of related risks and considering protective measures such as housing and filtering. N2 - 3D-Druck oder additive Herstellungsverfahren haben eine Menge vielversprechender und einzigartiger Vorteile. Insbesondere günstige 3D-Drucker für Polymere werden im privaten und ausbildenden Bereich zunehmend beliebter. Ihre Umweltfreundlichkeit kann aufgrund jüngst berichteter Emissionen ultrafeiner Partikel und vermuteter VOC-Emissionen infrage gestellt werden. Um 3D-Drucker für Polymere als mögliche Quelle von Innenraumluftverunreinigungen weiter zu untersuchen, charakterisierten wir die Emissionen feiner und ultrafeiner Partikel bei der Herstellung eines 3D-Objekts unter Verwendung zehn marktgängiger Polymerfilamente unter kontrollierten Bedingungen in einer Emissionsprüfkammer. Die VOC-Emissionen der verschiedenen Filamente wurden ebenfalls verglichen. Die zeitabhängigen und gemittelten Partikelemissionsraten wurden durch Anwendung eines einfachen Emissionsmodells bestimmt. Die Ergebnisse zeigen, dass unter vergleichbaren Bedingungen einige Filamente mit einer mittleren Rate von 10 KW - Emission KW - Ultrafine particles KW - VOC KW - 3D printer PY - 2018 SN - 0949-8036 SN - 0039-0771 VL - 78 IS - 3 SP - 79 EP - 87 PB - Springer-VDI-Verl. CY - Düsseldorf AN - OPUS4-44954 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Breitenbach, Romy A1 - Gerrits, Ruben A1 - Dementyeva, Polina A1 - Knabe, Nicole A1 - Schumacher, Julia A1 - Feldmann, Ines A1 - Radnik, Jörg A1 - Ryo, M. A1 - Gorbushina, Anna T1 - The role of extracellular polymeric substances of fungal biofilms in mineral attachment and weathering JF - npj Materials degradation N2 - The roles extracellular polymeric substances (EPS) play in mineral attachment and weathering were studied using genetically modified biofilms of the rock-inhabiting fungus Knufia petricola strain A95. Mutants deficient in melanin and/or carotenoid synthesis were grown as air-exposed biofilms. Extracted EPS were quantified and characterised using a combination of analytical techniques. The absence of melanin affected the quantity and composition of the produced EPS: mutants no longer able to form melanin synthesised more EPS containing fewer pullulan-related glycosidic linkages. Moreover, the melanin-producing strains attached more strongly to the mineral olivine and dissolved it at a higher rate. We hypothesise that the pullulan-related linkages, with their known adhesion functionality, enable fungal attachment and weathering. The released phenolic intermediates of melanin synthesis in the Δsdh1 mutant might play a role similar to Fe-chelating siderophores, driving olivine dissolution even further. These data demonstrate the need for careful compositional and quantitative analyses of biofilm-created microenvironments. KW - Biofilms PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-549025 DO - https://doi.org/10.1038/s41529-022-00253-1 SN - 2397-2106 VL - 6 SP - 1 EP - 11 PB - Springer Nature CY - London AN - OPUS4-54902 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hilgenberg, Kai A1 - Daum, Werner A1 - Maierhofer, Christiane A1 - Altenburg, Simon A1 - Bruno, Giovanni A1 - Heckel, Thomas A1 - Skrotzki, Birgit A1 - Zerbst, Uwe A1 - Kranzmann, Axel A1 - Bettge, Dirk A1 - Sommer, Konstantin A1 - Seeger, Stefan A1 - Nitsche, Michael A1 - Günster, Jens A1 - Evans, Alexander T1 - Additive manufacturing at the BAM: We focus on Safety JF - Advanced Materials and Processes N2 - In Germany, the Federal Institute for Materials Research and Testing (BAM) is addressing challenges in the implementation of additive manufacturing on the industrial landscape for safety-critical applications. KW - Process development KW - Additive Manufacturing KW - In-situ Process Monitoring KW - Non-destructive Materials KW - Characterisation KW - Safety KW - Fatigue KW - Environment KW - Standardisation PY - 2019 UR - https://static.asminternational.org/amp/201910/22/ SN - 0882-7958 VL - 177 IS - 7 SP - 22 EP - 26 PB - ASM International CY - Materials Park, OH, USA AN - OPUS4-49780 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -