TY - JOUR A1 - Brömme, T. A1 - Schmitz, C. A1 - Oprych, D. A1 - Wenda, A. A1 - Strehmel, V. A1 - Grabolle, Markus A1 - Resch-Genger, Ute A1 - Ernst, S. A1 - Reiner, K. A1 - Keil, D. A1 - Lüs, P. A1 - Baumann, H. A1 - Strehmel, B. T1 - Digital imaging of lithographic materials by radical photopolymerization and photonic baking with NIR diode lasers N2 - Photo-initiated cross-linking of multifunctional acrylic esters in polymeric binders was investigated based on digital imaging using the Computer-to-Plate (CtP) technology applying laser exposure in the near-infrared (NIR). Generation of initiating radicals occurs by electron transfer from the excited state of the NIR-sensitizer to the radical generator, an onium salt. Iodonium salts derived from several borates and those with the bis(trifluoromethylsulfonyl)imide anion resulted in lithographic materials with high sensitivity. Photo-induced electron transfer plays a major function to generate initiating radicals by a sensitized mechanism but thermal events also influence sensitivity of the coating. Internal conversion was the major deactivation pathway while a certain fraction of NIR-dye fluorescence was also available. A line shape focused laser system with emission in the NIR was successfully used to bake the materials. KW - Iodonium KW - Near-infrared laser KW - Photonic baking KW - Photophysics KW - Photopolymer PY - 2016 DO - https://doi.org/10.1002/ceat.201500453 SN - 0930-7516 SN - 1521-4125 VL - 39 IS - 1 SP - 13 EP - 25 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-35303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ostermann, Markus A1 - Herzel, Hannes A1 - Kühn, A. A1 - Mory, D. A1 - Wedell, R. T1 - Prozessanalytik mit Online-RFA und Online-LIBS für die Regelung der Aufarbeitung von Klärschlammaschen T1 - Online Process Analytics with XRF and LIBS for the Control of the Recycling of Sewage Sludge Ashes N2 - Es wurde ein Online-Analysenverfahren zur Bestimmung von Elementgehalten in Klär-schlammaschen und deren Produkten aus einem thermochemischen Verfahren entwickelt. Durch das thermochemische Verfahren können Wertstoffe aus den Aschen wieder für die Kreislaufwirtschaft nutzbar gemacht und Schadstoffe sicher entfernt werden. Das Analysensystem ist eine Methodenkombination von Online-Laser induzierter Plasma Spektroskopie (LIBS) und Online-Röntgenfluoreszenzanalyse (RFA). Robustheit und modulare Bauweise des Verfahrens sind wichtige Anforderungen um auch für andere Anwendungen nutzbar zu sein. N2 - An online analysis method has been developed for the determination of element mass fractions in sewage sludge ashes and their products originating from a thermochemical process. Within this process resources from the sewage sludge ashes can be re-utilized for the recycling economy and pollutants can be removed. The applied analysis system is a method combination of Online-laser induced breakdown spectroscopy (LIBS) and online- X-ray fluorescence (XRF). Robustness and a modular construction are important demands for successful future applications. KW - Klärschlammasche KW - Phosphor KW - Prozessanalytik KW - Röntgenfluoreszenzanalyse KW - LIBS PY - 2016 DO - https://doi.org/10.1002/cite.201500186 SN - 1522-2640 VL - 88 IS - 6 SP - 786 EP - 792 PB - Wiley-VCH Verlag GmbH & Co. KGaA CY - Weinheim, Germany AN - OPUS4-36334 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogl, Jochen A1 - Liesegang, D. A1 - Ostermann, Markus A1 - Diemer, J. A1 - Berglund, M. A1 - Quétel, C. A1 - Taylor, P. A1 - Heumann, K. T1 - Producing SI-traceable reference values for Cd, Cr and Pb amount contents in polyethylene samples from the Polymer Elemental Reference Material (PERM) project using isotope dilution mass spectrometry N2 - The present paper describes the certification of the amount content of Cd, Cr and Pb in two different polyethylene materials within the third phase of the Polyethylene Elemental Reference Material (PERM) project. The analytical procedure to establish the reference values for Cd, Cr and Pb amount contents in these materials is based on isotope dilution mass spectrometry used as a primary method of measurement. Cd and Pb were measured with inductively coupled plasma-mass spectrometry and Cr with positive thermal ionization-mass spectrometry. The decomposition of the polymer matrix was carried out using a high pressure asher. Reference values for amount content, traceable to the SI-system, have been obtained for these three elements in both of the polyethylene samples of PERM. For each of the certified amount content values an uncertainty budget was calculated using the method of propagation of uncertainties according to ISO and EURACHEM guidelines. The measurement procedures, as well as the uncertainty calculations, are described for all three elements. In order to keep the whole certification process as transparent as possible, the preparations of various reagents and materials as well as the sample treatment and blending are described in detail. The mass spectrometry measurements and the data treatment are also explained carefully. The various sources of uncertainty present in the procedure are displayed in the uncertainty budgets. The obtained combined uncertainties for the amount content values were less than 2% relative (k=1) for all investigated elements. The amount contents were in the ?mol/kg range, corresponding to mg/kg levels. KW - PERM KW - ICP-MS KW - PTI-MS KW - IDMS KW - Uncertainty budget KW - Certification KW - Polyethylene PY - 2000 DO - https://doi.org/10.1007/s007690000146 SN - 0949-1775 SN - 1432-0517 VL - 5 SP - 314 EP - 324 PB - Springer CY - Berlin AN - OPUS4-7217 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ostermann, Markus A1 - Berglund, M. A1 - Taylor, P. D. P. T1 - Measurement of the content of sulfur in gas oils using a high pressure asher, isotope dilution and thermal ionization mass spectrometry N2 - A new method has been developed for the measurement of sulfur in gas oils using a high pressure asher (HPA) for sample digestion. This, combined with a calibrated enriched isotopic reference material, and high precision mass spectrometry, makes it a powerful tool for an accurate and precise determination of the sulfur content in fossil fuels. The method described here was one of the methods used in the certification of the candidate reference materials BCR-104R, BCR-671 and BCR-672. Approximately 0.2 g of the gas oil samples were spiked with the spike isotopic reference material IRMM-646, which is enriched in 34S, and combusted in an HPA using nitric acid. The isotopes of sulfur were measured as arsenic monosulfides (AsS+) using a thermal ionization mass spectrometer equipped with a Faraday detector. The total uncertainty of the sulfur content (k = 2) is about 1%. The certified reference materials NIST SRM-2724b and NIST SRM-1619b and BCR-105 were used as part of the method validation work. The mass content of sulfur in BCR-104R was measured to be 1014 µg g-1, BCR-671 has 450 µg g-1 sulfur and BCR-672 shows a sulfur mass content of 201 µg g-1. The sulfur content of the candidate reference materials is homogeneous for the sample size used. KW - TIMS KW - Gas-oil KW - Reference materials KW - Isotope dilution KW - Sulfur PY - 2002 DO - https://doi.org/10.1039/B111140J SN - 0267-9477 SN - 1364-5544 VL - 17 IS - 10 SP - 1368 EP - 1372 PB - Royal Society of Chemistry CY - London AN - OPUS4-1214 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schilling, Markus A1 - Niebergall, Ute A1 - Alig, I. A1 - Oehler, H. A1 - Lellinger, D. A1 - Meinel, Dietmar A1 - Böhning, Martin T1 - Crack propagation in PE-HD induced by environmental stress cracking (ESC) analyzed by several imaging techniques N2 - Different imaging techniques were employed to monitor Full Notch Creep Test (FNCT) experiments addressing environmental stress cracking in more detail. The FNCT is a well-established test method to assess slow crack growth and environmental stress cracking of polymer materials, especially polyethylene. The standard test procedure, as specified in ISO 16770, provides a simple comparative measure of the resistance to crack growth of a certain material based on the overall time to failure when loaded with a well-defined mechanical stress and immersed in a liquid medium promoting crack propagation. Destructive techniques which require a direct view on the free fracture surface, such as light microscopy and laser scanning microscopy, are compared to non-destructive techniques, i.e. scanning acoustic microscopy and xray micro computed tomography. All methods allow the determination of an effective crack length. Based on a series of FNCT specimens progressively damaged for varied Durations under standard test conditions, the estimation of crack propagation rates is also enabled. Despite systematic deviations related to the respective Imaging techniques, this nevertheless provides a valuable tool for the detailed evaluation of the FNCT and its further development. KW - Environmental stress cracking (ESC) KW - Slow crack growth (SCG) KW - Full notch creep test (FNCT) KW - X-ray computed tomography (CT) KW - Laser scanning microscopy (LSM) KW - Scanning acoustic microscopy (SAM) PY - 2018 DO - https://doi.org/10.1016/j.polymertesting.2018.08.014 SN - 0142-9418 SN - 1873-2348 VL - 70 SP - 544 EP - 555 PB - Elsevier AN - OPUS4-45766 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erler, A. A1 - Riebe, D. A1 - Beitz, T. A1 - Löhmannsröben, H.-G. A1 - Leenen, M. A1 - Pätzold, S. A1 - Ostermann, Markus A1 - Wójcik, M. T1 - Mobile Laser-Induced Breakdown Spectroscopy for Future Application in Precision Agriculture—A Case Study N2 - In precision agriculture, the estimation of soil parameters via sensors and the creation of nutrient maps are a prerequisite for farmers to take targeted measures such as spatially resolved fertilization. In this work, 68 soil samples uniformly distributed over a field near Bonn are investigated using laser-induced breakdown spectroscopy (LIBS). These investigations include the determination of the total contents of macro- and micronutrients as well as further soil parameters such as soil pH, soil organic matter (SOM) content, and soil texture. The applied LIBS instruments are a handheld and a platform spectrometer, which potentially allows for the single-point measurement and scanning of whole fields, respectively. Their results are compared with a high-resolution lab spectrometer. The prediction of soil parameters was based on multivariate methods. Different feature selection methods and regression methods like PLS, PCR, SVM, Lasso, and Gaussian processes were tested and compared. While good predictions were obtained for Ca, Mg, P, Mn, Cu, and silt content, excellent predictions were obtained for K, Fe, and clay content. The comparison of the three different spectrometers showed that although the lab spectrometer gives the best results, measurements with both field spectrometers also yield good results. This allows for a method transfer to the in-field measurements KW - LIBS KW - Precision agriculture KW - Soil KW - Multivariate methods KW - Feature selection PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580777 DO - https://doi.org/10.3390/s23167178 VL - 23 IS - 16 SP - 1 EP - 17 PB - MDPI AG CY - Basel, Schweiz AN - OPUS4-58077 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kazlagić, Anera A1 - Stephan, D. A1 - Ostermann, Markus A1 - Possolo, A. A1 - Vogl, Jochen T1 - Fingerprinting Portland cements by means of 87Sr/86Sr and 143Nd/144Nd isotope ratios and geochemical profiles N2 - This study uses conventional 87Sr/86Sr and 143Nd/144Nd isotope and interelement ratios of Ca, Sr, K, Mn, Mg and Ti as fingerprints for provenancing ordinary Portland cements (OPC). Herein, the first database of Sr and Nd isotope ratios investigated in OPCs, stemming from 29 cement plants located worldwide, was created. The results show that the Sr isotope ratios of OPCs are higher than those of seawater from the observed geological period. The spread of 143Nd/144Nd in OPCs is not as large as the spread for 87Sr/86Sr isotope ratios. However, the combination of both Sr and Nd isotope ratios provides the potential for distinguishing between cements of different production sites. Most of the OPCs investigated have measurable differences in their 87Sr/86Sr and 143Nd/144Nd isotope ratios, which can be employed as a valuable analytical fingerprinting tool. In the case of equivocal results, divisive hierarchical clustering was employed to help overcome this issue. The construction of geochemical profiles allowed the computing of suitably defined distances between cements and clustering them according to their chemical similarity. By applying this methodology, successful fingerprinting was achieved in 27 out of the 29 ordinary Portland cements that were analysed. KW - Elemental fingerprints KW - Geochemistry KW - Portland cement KW - Sr and Nd isotope analysis KW - Statistical analysis PY - 2023 DO - https://doi.org/10.1680/jadcr.23.00018 SN - 0951-7197 VL - 36 IS - 6 SP - 260 EP - 271 PB - Emerald Publishing Limited AN - OPUS4-57979 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hamann, F. A1 - Brehm, Robert A1 - Pauli, Jutta A1 - Grabolle, Markus A1 - Frank, W. A1 - Kaiser, W.A. A1 - Fischer, D. A1 - Resch-Genger, Ute A1 - Hilger, I. T1 - Controlled modulation of serum protein binding and biodistribution of asymmetric cyanine dyes by variation of the number of sulfonate groups N2 - To assess the suitability of asymmetric cyanine dyes for in vivo fluoro-optical molecular imaging, a comprehensive study on the influence of the number of negatively charged sulfonate groups governing the hydrophilicity of the DY-67x family of asymmetric cyanines was performed. Special attention was devoted to the plasma protein binding capacity and related pharmacokinetic properties. Four members of the DY-67x cyanine family composed of the same main chromophore, but substituted with a sequentially increasing number of sulfonate groups (n = 1−4; DY-675, DY-676, DY-677, DY-678, respectively), were incubated with plasma proteins dissolved in phosphate-buffered saline. Protein binding was assessed by absorption spectroscopy, gel electrophoresis, ultrafiltration, and dialysis. Distribution of dye in organs was studied by intraveneous injection of 62 nmol dye/kg body weight into mice (n = 12; up to 180 minutes postinjection) using whole-body near-infrared fluorescence imaging. Spectroscopic studies, gel electrophoresis, and dialysis demonstrated reduced protein binding with increasing number of sulfonate groups. The bovine serum albumin binding constant of the most hydrophobic dye, DY-675, is 18 times higher than that of the most hydrophilic fluorophore, DY-678. In vivo biodistribution analysis underlined a considerable influence of dye hydrophilicity on biodistribution and excretion pathways, with the more hydrophobic dyes, DY-675 and DY-676, accumulating in the liver, followed by strong fluorescence signals in bile and gut owing to accumulation in feces and comparatively hydrophilic DY-678-COOH accumulating in the bladder. Our results demonstrate the possibility of selectively controlling dye-protein interactions and, thus, biodistribution and excretion pathways via proper choice of the fluorophore's substitution pattern. This underlines the importance of structure-property relationships for fluorescent labels. Moreover, our data could provide the basis for the rationalization of future contrast agent developments. PY - 2011 DO - https://doi.org/10.2310/7290.2011.00005 SN - 1535-3508 SN - 1536-0121 VL - 10 IS - 4 SP - 258 EP - 269 PB - Decker CY - Hamilton, Ont. AN - OPUS4-24311 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Jordan, T. A1 - Askar, Enis A1 - Holtappels, Kai A1 - Jopen, M. A1 - Stoll, U. A1 - Reinecke, E.-A. A1 - Krause, U. A1 - Beyer, M. A1 - Markus, D. T1 - Fuels – Introduction | Hydrogen safety N2 - The introduction of hydrogen as a safe energy carrier needs a robust knowledge base, tools for the design and safety assessment of hydrogen technologies built on it, and an internationally harmonized set of standards and regulations. Many of the innovative technologies imply hydrogen at high pressures and/or cryogenic temperatures, with which private users come into contact for the first time in distributed applications. In order to avoid over-conservative, expensive safety solutions, while at the same time demonstrating the usability and safety of hydrogen applications and maintaining acceptance for the technology, safety research must also keep pace with, or better yet anticipate, trends in technological development. Thus, this overview article describes not only the current state of knowledge and technology regarding hydrogen safety, but also its further development. KW - Explosion protection KW - Accidental scenarios KW - Hazard and risk assessment KW - Regulations codes and standards (RCS) KW - Ignition KW - Hydrogen storage KW - Energy carrier PY - 2024 SN - 978-0-1240-9547-2 DO - https://doi.org/10.1016/B978-0-323-96022-9.00195-X VL - 2nd Edition SP - 1 EP - 15 PB - Elsevier B.V. AN - OPUS4-59940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hussung, D. R. A1 - Kurz, J. H. A1 - Stoppel, Markus T1 - Automatisierte, zerstörungsfreie Prüftechnik für großflächige Stahlbetontragwerke - Ein Anwendungsbeispiel T1 - Automated non-destructive inspection techniques for large reinforced concrete constructions - An example of use N2 - Eine Vielzahl zerstörungsfreier Prüfverfahren hat in den letzten Jahren Einzug in die Bauwerksuntersuchung gehalten. Um die Aussagekraft der Einzelverfahren zu erhöhen und den wirtschaftlichen Einsatz weiter voranzubringen, lag es nahe, die Verfahren kombiniert auf einer automatisierten Plattform zu montieren. Zu diesem Zweck wurde das BetoScan-System entwickelt. Um weitere Erfahrungen mit dem BetoScan-System zu erhalten, wurde ein langjährig genutztes Parkhaus aus Stahlbeton mit Gussasphaltfahrbahn als Untersuchungsobjekt ausgewählt. Bei der experimentellen Bauwerksuntersuchung wurden die Verfahren Wirbelstrom, Radar, Ultraschall und Mikrowelle zum Einsatz gebracht. Von der Anwendung des Systems und der Auswertung der Ergebnisse wird in diesem Beitrag berichtet. N2 - In recent years a variety of non-destructive evaluation methods are more and more used for the inspection of constructions. Increasing the information value of inspections and the economic aspects of applications leads to a combination of methods on an automated system. Therefore, the BetoScan robot was developed. Gaining more experience in applications was realized with the inspection of a car park which was unused for several years. The building was made of reinforced concrete with melted asphalt as floor coating. Within the frame of the inspections eddy current, radar, ultrasound and microwaves were used. The application of the BetoScan system and the results are presented in this article. KW - Automatisierte zerstörungsfreie Prüfung KW - Bauwesen KW - Kombination KW - Verfahren KW - Bauwerksüberwachung KW - BetoScan-System KW - Dauerhaftigkeit KW - Gussasphalt KW - Instandsetzung KW - Lebensdauer KW - Mikrowelle KW - Nachhaltigkeit KW - Qualitätssicherung KW - Radar KW - Ultraschall-Prüfung KW - ZfP-Verfahren KW - Bauwerkserhaltung/Sanierung KW - Allgemeines PY - 2012 DO - https://doi.org/10.1002/best.201200048 SN - 0005-9900 SN - 1437-1006 VL - 107 IS - 12 SP - 794 EP - 804 PB - Ernst CY - Berlin AN - OPUS4-27588 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abdelkhalik, A. A1 - Askar, Enis A1 - Markus, D. A1 - Stolz, T. A1 - Brandes, E. A1 - Zakel, S. T1 - Explosion regions of 1,3-dioxolane/nitrous oxide and 1,3-dioxolane/air with different inert gases - Experimental data and numerical modelling N2 - In this study, experimental determination and modelling investigations for the explosion regions of 1,3-dioxolane/inert gas/N2O and 1,3-dioxolane/inert gas/air mixtures were carried out and compared. The experimental measurements were carried out at 338 K and atmospheric pressure according to EN1839 method T using the inert gases N2, CO2, He and Ar. The results showed that the ratio of the lower explosion limit in N2O (LELN2O) to the lower explosion limit in air (LELair) is 0.52 and the ratio of the maximum oxygen content in air (MOCair) to the limiting oxidizer fraction in nitrous oxide (LOFN2O) is 0.36 ± 0.02 independent of the inert gas. When comparing the inert gas amount at the apex based on the pure oxidizing component, which is O2 in case of air, N2O-containing mixtures need less inert gas to reach the limiting oxidizer quantity whereas the efficiency of inert gases is in the same order. The coefficients of nitrogen equivalency however were found to differ to some extent. The explosion regions of 1,3-dioxolane/inert gas/oxidizer mixtures were modelled using the calculated adiabatic flame temperature profile (CAFTP) method as well as corrected adiabatic flame temperatures. The results indicate good agreement with experimental data for CO2, N2 and Ar- containing mixtures. The noticeable deviations that occur when He is the inert gas are due to the lacking transport data of that mixture. KW - Explosion limits KW - Flammability KW - CAFTP KW - Adiabatic Flame Temperatures PY - 2021 DO - https://doi.org/10.1016/j.jlp.2021.104496 SN - 0950-4230 VL - 71 SP - 4496 PB - Elsevier Ltd AN - OPUS4-52849 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Askar, Enis A1 - Aksam, A. A1 - Brandes, E. A1 - Markus, D. A1 - Stolz, T. T1 - Berechnung der Explosionsbereiche von Alkoholen, Ketonen und halogenierten Kohlenwasserstoffen im Gemisch mit Inertgasen N2 - Die Explosionsbereiche für Dreistoffsysteme aus Brennstoff Inertgas und Luft wurden nach dem Modell der konstanten adiabatischen Flammentemperaturprofile berechnet. Für die Parametrisierung des halbempirischen Modells muss der Explosionsbereich für ein bestimmtes Dreistoffsystem aus Brennstoff, Inertgas und Luft bekannt sein. Dann lassen sich Explosionsbereiche desselben Brennstoffs mit einem beliebigen Inertgas und bei einer beliebigen Temperatur berechnen. Ergänzend zu früheren Arbeiten, in denen die Explosionsbereiche für Brenngase aus der homologen Reihe der Alkane und Alkene berechnet worden sind, wurden nun die Berechnungen für 1-Propanol, Aceton und Difluormethan durchgeführt. Als Inertgase wurden neben Stickstoff und Kohlendioxid auch die Edelgase Argon und Helium berücksichtigt. Für die Berechnung der Explosionsbereiche in Systemen mit Helium, ist das Modell erweitert worden, so dass auch die Transporteigenschaften (d.h. Wärmeleitfähigkeit, Diffusionskoeffizient) der Komponenten berücksichtigt werden. Weiterhin ist eine Möglichkeit zur praxisnahen Berechnung der Spitze des Explosionsbereichs implementiert worden. Die Ergebnisse zeigen insgesamt, dass die Berechnung der Explosionsbereiche für Alkohole, Ketone und halogenierte Kohlenwasserstoffe mit ähnlicher Genauigkeit wie für Alkane und Alkene möglich ist. Die vorgenommenen Modifikationen sind geeignet, um auch eine Berechnung für Gasgemische mit Helium durchzuführen, dessen starke inertisierende Wirkung im Vergleich zu den Inertgasen Argon oder Stickstoff vor allem auf den stark unterschiedlichen Transporteigenschaften beruht. KW - Explosionsgrenzen KW - Inertisierung KW - Modell der konstanten Flammentemperaturen KW - Explosionsschutz PY - 2020 DO - https://doi.org/10.7795/310.20200199 SN - 0030-834X VL - 130 IS - 1 SP - 25 EP - 29 AN - OPUS4-50945 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ostermann, Markus A1 - Herzel, Hannes A1 - Adam, Christian A1 - Kühn, A. A1 - Wedell, R. A1 - Mory, D. T1 - Integrierte Systeme (RFA und LIBS) zur Düngemittelgewinnung und zum Management der Bodenfruchtbarkeit N2 - Aufgrund der natürlichen und vom Menschen verursachten Heterogenität von Böden erfordert der Erhalt und die Verbesserung ihrer Fruchtbarkeit durch landwirtschaftliche Bewirtschaftungsmaßnahmen sorgfältig geplante Ent-scheidungen, die auf einer detaillierten Erfassung der Bodeneigenschaften und einem vertieften Verständnis der Bodenprozesse beruhen. Es ist bekannt, dass die konventionelle, flächen-einheitliche Bewirtschaftung Ertragsver-luste durch zu geringe Bewirtschaftungsintensität (z. B. Düngung) auf einen Teil der Fläche verursacht, während andere Teile des Feldes zu hohe Dosen erhalten und es dadurch zu Verschwendung von Ressourcen und zu Um-weltbelastungen kommt. Trotz der Verfügbarkeit von Technologien für ortsspezifische Düngung ist die Akzeptanz ortsspezifischer Bewirtschaftung (Precision Agriculture) in der Praxis noch gering. Ein wesentlicher Grund dafür ist das Fehlen von kostengünstigen Methoden zur Erfassung der bewirtschaftungsrelevanten Bodenmerkmale. So-wohl für die elementanalytische Untersuchung von Böden als auch für die Untersuchung von Ausgangsmaterialien (z.B. Klärschlammaschen) für ihre Verwendung als Dünger ist eine zuverlässige Analytik und Prozessüberwachung erforderlich. T2 - 11. Kolloquium Arbeitskreis Prozessanalytik CY - Wien, Austria DA - 30.11.2015 KW - LIBS KW - Online-RFA KW - Düngemittelgewinnung KW - Bodenfruchtbarkeit KW - BONARES PY - 2015 SP - 23 EP - 24 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-38843 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Zeeuw, C. A1 - Teixeira de Freitas, S. A1 - Zarouchas, D. A1 - Schilling, Markus A1 - Lopes Fernandes, R. A1 - Portella, Pedro Dolabella A1 - Niebergall, Ute T1 - Creep behaviour of steel bonded joints under hygrothermal conditions N2 - The aim of this research is to study the influence of moisture absorption at low moisture contents on the creep behaviour of an epoxy adhesive in steel bonded joints. Single lap joints were manufactured using high strength steel adherends and a two-component epoxy adhesive. The single lap joints were tested at load Levels corresponding to average lap shear stresses of±5%, 15%, 30% and 45% of the dry lap shear strength in both 40 °C air and 40 °C distilled water. Specimens were not pre-aged to be able to analyse the coupled effect of moisture and loading. The test results show that an increase in the load level resulted in an increase in the instantaneous strain and in the creep strain rate. The creep strain of single lap joints loaded in water was generally larger than for the ones loaded in air. For joints loaded in water the creep behaviour was found to be dependent on the moisture concentration in the adhesive. At low moisture percentages creep was suppressed, resulting in a lower instantaneous strain. At higher moisture percentages creep was promoted, resulting in a larger strain rate. The suppression of creep at low moisture percentages is attributed to water molecules bonding to the epoxy macromolecules, resulting in a reduction in molecular mobility and a smaller creep strain. At higher moisture percentages the plasticizing effect of the water dominates, resulting in a larger creep strain. The Maxwell threeelement solid model and Kelvin-Voigt three-element solid model were used to simulate the creep behaviour of the single lap joints loaded in air and water. The models gave good representations of the creep Response across the different load levels in both water and air, they were however unable to give a correct representation of the instantaneous strain of the single lap joints loaded in water. This is attributed to the models being unable to account for the present short-term relaxation process that is dependent on the moisture concentration. KW - C. lap-shear KW - D. aging KW - D. creep D. viscoelasticity KW - Hygrothermal KW - Viscoelastic model PY - 2019 DO - https://doi.org/10.1016/j.ijadhadh.2019.03.002 SN - 0143-7496 VL - 91 SP - 54 EP - 63 PB - Elsevier AN - OPUS4-47538 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abdelkhalik, A. A1 - Askar, Enis A1 - Markus, D. A1 - Brandes, E. A1 - Stolz, T. T1 - Explosion regions of acetone and alcohol/inert gas/air mixtures at high temperatures and atmospheric pressure N2 - The explosion regions of 1-propanol, 2-propanol, acetone and 1-butanol in air were measured in the presence of CO2, He, N2 and Ar in accordance with EN1839 method T at high temperatures and at atmospheric pressure. The experimental results show that 1-propanol, 2-propanol and acetone have very similar lower explosion limits (LELs). 1-Butanol shows a slightly wider explosion area near the LEL line. In addition, the explosion regions of all combustible/inert gas/air mixtures were calculated with the method of constant adiabatic flame temperature profiles (CAFTP), using the flame temperature profile along the explosion region boundary curve of each combustible/N2/air mixture as a reference to determine the explosion regions of combustible/inert gas/air mixtures with inert gases other than N2 at different initial temperatures. To calculate the explosion regions for systems containing He, the calculation method was modified to include the very different physical transport properties of He. Moreover, the procedure for calculating the apexes in the ternary explosion diagrams was modified. The calculation results show good agreement with the experimental results. KW - Explosion limits KW - Elevated temperatures KW - Alcohols KW - CAFTP KW - Acetone PY - 2019 DO - https://doi.org/10.1016/j.jlp.2019.103958 SN - 0950-4230 VL - 62 SP - 103958, 1 EP - 8 PB - Elsevier AN - OPUS4-49030 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Askar, Enis A1 - Aksam, A. A1 - Brandes, E. A1 - Markus, D. A1 - Stolz, T. T1 - Berechnung der Explosionsbereiche von Alkoholen, Ketonen und halogenierten Kohlenwasserstoffen im Gemisch mit Inertgasen N2 - Die Explosionsbereiche für Dreistoffsysteme aus Brennstoff, Inertgas und Luft wurden nach dem Modell der konstanten adiabatischen Flammentemperaturprofile berechnet. Für die Parametrisierung des halbempirischen Modells muss der Explosionsbereich für ein bestimmtes Dreistoffsystem aus Brennstoff, Inertgas und Luft bekannt sein. Dann lassen sich Explosionsbereiche desselben Brennstoffs mit einem beliebigen Inertgas und bei einer beliebigen Temperatur berechnen. Ergänzend zu früheren Arbeiten, in denen die Explosionsbereiche für Brenngase aus der homologen Reihe der Alkane und Alkene berechnet worden sind, wurden nun die Berechnungen für 1-Propanol, Aceton und Difluormethan durchgeführt. Als Inertgase wurden neben Stickstoff und Kohlendioxid auch die Edelgase Argon und Helium berücksichtigt. Für die Berechnung der Explosionsbereiche in Systemen mit Helium, ist das Modell erweitert worden, so dass auch die Transporteigenschaften (d.h. Wärmeleitfähigkeit, Diffusionskoeffizient) der Komponenten berücksichtigt werden. Weiterhin ist eine Möglichkeit zur praxisnahen Berechnung der Spitze des Explosionsbereichs implementiert worden. Die Ergebnisse zeigen insgesamt, dass die Berechnung der Explosionsbereiche für Alkohole, Ketone und halogenierte Kohlenwasserstoffe mit ähnlicher Genauigkeit wie für Alkane und Alkene möglich ist. Die vorgenommenen Modifikationen sind geeignet, um auch eine Berechnung für Gasgemische mit Helium durchzuführen, dessen starke inertisierende Wirkung im Vergleich zu den Inertgasen Argon oder Stickstoff vor allem auf den stark unterschiedlichen Transporteigenschaften beruht. Für die Analyse der physikalischen Vorgänge, die zur Zündung führen, ist eine spezielle Kontaktvorrichtung entwickelt worden. Damit können die Entladungen > 200 µm Länge und mit einer Dauer von > 500 µs an einer bestimmbaren Position erzeugt und untersucht werden. Für die Entladungen an der Zündgrenze bei niedrigen Spannungs- und Stromwerten (max. 30 V, 30 bis 100 mA Konstantstrombegrenzung) sind die Bedingung für die Erzeugung ermittelt worden. Das sind die Rauheit auf der Kontaktoberfläche, die langsame Kontaktöffnungsbewegung und eine geeignet regelnde Spannungsquelle mit Konstantstrombegrenzung. Damit sind für diese Entladungen an der Zündgrenze die Strom-Spannungs-Kennlinie, das Spektrum mit dominierenden Linien von Cadmium-Metalldampf sowie die Temperaturverläufe ermittelt worden. T2 - 15. BAM-PTB-Kolloquium zur chemischen und physikalischen Sicherheitstechnik CY - Brunswick, Germany DA - 21.05.2019 KW - Explosionsgrenzen KW - Inertisierung KW - Modell der konstanten Flammentemperaturen KW - Explosionsschutz PY - 2019 DO - https://doi.org/10.7795/210.20190521J SP - 1 EP - 9 AN - OPUS4-48947 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simons, C. A1 - Mans, C. A1 - Hanning, S. A1 - Janßen, A. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Ostermann, Markus A1 - Michaelis, Matthias A1 - Wienold, Julia A1 - Alber, D. A1 - Kreyenschmidt, M. T1 - Study on microscopic homogeneity of polymeric candidate reference materials BAM H001-BAM H010 by means of synchrotron µ-XRF and LA-ICP-MS N2 - In this study the microscopic homogeneity of the newly developed plastic reference materials BAM H001-BAM H010 was investigated. The materials consist of an acrylonitryle-butadien-styrene terpolymer, doped with different amounts of the elements Br, Cd, Cr, Hg and Pb. For the quantitative determination of the degree of homogeneity, a procedure proposed by Kempenaers et al. (Fresenius J. Anal. Chem., 2001, 369, 733-737) was used. On every sample an extensive number of different points were analyzed and standard deviation for every element mentioned above was used to calculate a minimal sampling mass that is necessary to reach a certain level of uncertainty caused by inhomogeneity (mmin,5%). The experiments were taken out with synchrotron µ-XRF (SR µ-XRF) at BESSYII in Berlin and by laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS). The calculated values for mmin,5% of both techniques showed comparable results for all elements. It could be shown that the materials are suitable for calibration of micro analytic techniques if at least 64 µg are used. KW - XRF KW - LA-ICP-MS KW - RoHS KW - CRM PY - 2010 DO - https://doi.org/10.1039/b917008a SN - 0267-9477 SN - 1364-5544 VL - 25 SP - 40 EP - 43 PB - Royal Society of Chemistry CY - London AN - OPUS4-20938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jordan, T. A1 - Askar, Enis A1 - Holtappels, Kai A1 - Deeg, S. A1 - Jopen, M. A1 - Stoll, U. A1 - Reinecke, E.-A. A1 - Krause, U. A1 - Beyer, M. A1 - Markus, D. T1 - Stand der Kenntnisse und Technik bezüglich Wasserstoffsicherheit N2 - Die Einführung von Wasserstoff als sicherer Energieträger braucht eine robuste Wissensbasis, darauf aufgebaute Werkzeuge zur Auslegung und Sicherheitsbewertung von Wasserstofftechnologien und ein international harmonisiertes Regelwerk. Viele der innovativen Technologien implizieren Wasserstoff bei hohen Drücken und/oder kryogenen Temperaturen, mit denen in verteilten Anwendungen erstmalig private Nutzer in Kontakt kommen. Um überkonservative, teure Sicherheitslösungen zu vermeiden, gleichzeitig aber die Einsetzbarkeit und Sicherheit von Wasserstoffanwendungen zu demonstrieren und die Akzeptanz für die Technologie aufrecht zu halten, muss auch die Sicherheitsforschung mit den Trends der technologischen Entwicklung Schritt halten, oder sie besser noch antizipieren. So beschreibt dieser Überblicksartikel nicht nur den gegenwärtigen Stand der Kenntnisse und Technik bezüglich Wasserstoffsicherheit, sondern auch ihre Weiterentwicklung. KW - Alternative Energieträger KW - Explosionsschutz KW - Flüssigwasserstoff KW - Unfallszenarien KW - Wasserstoffspeicherung KW - Sicherheitsbewertung KW - Regelsetzung KW - Gefährdungs- und Risikobeurteilung PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593629 DO - https://doi.org/10.1002/cite.202300141 SN - 0009-286X VL - 96 IS - 1-2 SP - 1 EP - 20 PB - Wiley-VCH AN - OPUS4-59362 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abdelkhalik, A. A1 - Askar, Enis A1 - Markus, D. A1 - Brandes, E. A1 - El-Sayed, I. A1 - Hassan, M. A1 - Nour, M. A1 - Stolz, T. T1 - Explosion regions of propane, isopropanol, acetone, and methyl acetate/inert gas/air mixtures N2 - The explosion regions for propane, isopropanol, acetone, and methyl acetate with air in the presence of nitrogen, argon, helium, and carbon dioxide were determined experimentally according to EN 14756/EN1839, method T. Except for propane, all the measurements were executed at 323 K and 1 bar. Propane experiments were carried out at 293 K and 1 bar. The results show that for the same type of inert gas, propane, isopropanol, and acetone have great closeness concerning the concentration of the inert gas at the apex of the explosion envelope in a ternary diagram with air as oxidizer. This leads to consistency in the limiting oxygen concentration (LOC) and minimum required amount of inert gas (MAI) values. Concerning methyl acetate, the apex was always reached at higher percentages of inert gases compared with the other fuels. This can be attributed to the presence of two oxygen atoms inside the chemical structure. Calculation of the explosion regions was carried out based on calculated adiabatic flame temperature (CAFT) method. The flame temperatures for the experimentally determined fuel/air/N2 mixtures were calculated. Then, these temperatures were used to predict the explosion limits of similar mixtures with other inert gases than nitrogen. The modeling results show reasonable agreement with the experimental results. KW - Flammability limits KW - Model of constant adiabatic flame temperatures (CAFT) KW - Inertisation KW - Explosion protection PY - 2016 DO - https://doi.org/10.1016/j.jlp.2016.04.001 SN - 0950-4230 VL - 2016/43 SP - 669 EP - 675 PB - Elsevier Ltd. CY - Oxford, UK AN - OPUS4-37996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lancaster, Shaun T. A1 - Sahlin, Eskil A1 - Oelze, Marcus A1 - Ostermann, Markus A1 - Vogl, Jochen A1 - Laperche, Valérie A1 - Touze, Solène A1 - Ghestem, Jean-Philippe A1 - Dalencourt, Claire A1 - Gendre, Régine A1 - Stammeier, Jessica A1 - Klein, Ole A1 - Pröfrock, Daniel A1 - Košarac, Gala A1 - Jotanovic, Aida A1 - Bergamaschi, Luigi A1 - Di Luzio, Marco A1 - D’Agostino, Giancarlo A1 - Jaćimović, Radojko A1 - Eberhard, Melissa A1 - Feiner, Laura A1 - Trimmel, Simone A1 - Rachetti, Alessandra A1 - Sara-Aho, Timo A1 - Roethke, Anita A1 - Michaliszyn, Lena A1 - Pramann, Axel A1 - Rienitz, Olaf A1 - Irrgeher, Johanna T1 - Evaluation of X-ray fluorescence for analysing critical elements in three electronic waste matrices: A comprehensive comparison of analytical techniques N2 - As the drive towards recycling electronic waste increases, demand for rapid and reliable analytical methodology to analyse the metal content of the waste is increasing, e.g. to assess the value of the waste and to decide the correct recycling routes. Here, we comprehensively assess the suitability of different x-ray fluorescence spectroscopy (XRF)-based techniques as rapid analytical tools for the determination of critical raw materials, such as Al, Ti, Mn, Fe, Co, Ni, Cu, Zn, Nb, Pd and Au, in three electronic waste matrices: printed circuit boards (PCB), light emitting diodes (LED), and lithium (Li)-ion batteries. As validated reference methods and materials to establish metrological traceability are lacking, several laboratories measured test samples of each matrix using XRF as well as other independent complementary techniques (instrumental neutron activation analysis (INAA), inductively coupled plasma mass spectrometry (ICP-MS) and ICP optical emission spectrometry (OES)) as an inter-laboratory comparison (ILC). Results highlighted key aspects of sample preparation, limits of detection, and spectral interferences that affect the reliability of XRF, while additionally highlighting that XRF can provide more reliable data for certain elements compared to digestion-based approaches followed by ICP-MS analysis (e.g. group 4 and 5 metals). A clear distinction was observed in data processing methodologies for wavelength dispersive XRF, highlighting that considering the metals present as elements (rather than oxides) induces overestimations of the mass fractions when compared to other techniques. Eventually, the effect of sample particle size was studied and indicated that smaller particle size (<200 μm) is essential for reliable determinations. KW - XRF KW - WEEE KW - PCB KW - Battery KW - LED KW - Recycling PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614060 DO - https://doi.org/10.1016/j.wasman.2024.10.015 VL - 190 SP - 496 EP - 505 PB - Elsevier B.V. AN - OPUS4-61406 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hearn, R. A1 - Berglund, M. A1 - Ostermann, Markus A1 - Pusticek, N. A1 - Taylor, P.D.P. T1 - A comparison of high accuracy isotope dilution techniques for the measurement of low level sulfur in gas oils N2 - A comparison of high accuracy methods for the analysis of total sulfur in gas oils by three metrology institutes is described. The work contains a comparison of three different aspects of the analysis: sample digestion, instrumental measurement and isotope dilution strategies. Thermal ionisation mass spectrometry (TIMS) in combination with high pressure asher (HPA) or Carius tube digestion has traditionally been used for such high accuracy analysis. However, this paper demonstrates that the faster, less laborious technique of ICP-MS in combination with microwave digestion is equally capable. Results from the comparison experiments show excellent agreement for fuel samples containing sulfur concentrations in the range 11–200 µg g-1. This excellent agreement across the different sample preparation, measurement and isotope dilution techniques has been exploited in the certification of two new diesel fuel reference materials. KW - Sulfur KW - Gas oil KW - Isotope dilution KW - ICP-MS KW - TIMS KW - Uncertainty PY - 2005 DO - https://doi.org/10.1016/j.aca.2004.10.070 SN - 0003-2670 SN - 1873-4324 SN - 0378-4304 VL - 532 IS - 1 SP - 55 EP - 60 PB - Elsevier CY - Amsterdam AN - OPUS4-7280 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogl, Jochen A1 - Quétel, C. A1 - Ostermann, Markus A1 - Papadakis, I. A1 - Van Nevel, L. A1 - Taylor, P.D.P. T1 - Contribution to the certification of B, Cd, Mg, Pb, Rb, Sr, and U in a natural water sample for the International Measurement Evaluation Programme Round 9 (IMEP-9) using ID-ICP-MS N2 - The present paper describes the contribution of the Institute for Reference Materials and Measurements to the certification of B, Cd, Mg, Pb, Rb, Sr, and U amount contents in a natural water sample, in round 9 of the International Measurement Evaluation Programme (IMEP-9). The analytical procedure to establish the reference values for B, Cd, Mg, Pb, Rb, Sr, and U amount contents was based on isotope dilution inductively coupled plasma-mass spectrometry used as a primary method of measurement. Applying this procedure reference values, traceable to the SI, were obtained for the natural water sample of IMEP-9. For each of the certified amount contents presented here a total uncertainty budget was calculated using the method of propagation of uncertainties according to ISO and EURACHEM guidelines. The measurement procedures, as well as the uncertainty calculations are described for all seven elements mentioned above. In order to keep the whole certification process transparent and so traceable, the preparations of various reagents and materials as well as the sample treatment and blending, the measurements themselves, and finally the data treatment are described in detail. Explanations focus on Pb as a representative example. The total uncertainties (relative) obtained were less than 2% for all investigated elements at amount contents in the pmol/kg up to the high 7mol/kg range, corresponding to low 7g/kg and mg/kg levels. KW - IMEP-9 KW - ID-ICP-MS KW - IDMS KW - Uncertainty budget KW - Certification PY - 2000 DO - https://doi.org/10.1007/s007690000145 SN - 0949-1775 SN - 1432-0517 VL - 5 SP - 272 EP - 279 PB - Springer CY - Berlin AN - OPUS4-7216 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -