TY - CONF
A1 - Visileanu, Emilia
A1 - Catalin Grosu, Marian
A1 - Tiberiu Miclea, Paul
A1 - Altmann, Korinna
A1 - Brossell, Dirk
T1 - Methods for the collection and characterization of airborne particles in the textile industry
N2 - Airborne particulate matter is one of the main air pollutants. Their impact on mortality, and the occurrence of pulmonary and cardiovascular complications, have been the subject of numerous studies. Airborne particles are complex mixtures of organic and inorganic substances from different sources of particle emissions. Particulate Matter (PM) particles are classified according to their aerodynamic diameter expressed in µm and can vary from coarse (PM 10) to fine (less than PM 2.5). These diameter considerations are fundamental because they condition the penetration of particles into the bronchopulmonary system and the body. In recent years, there has been an interest in so-called “ultra-fine” particles, with a diameter of 0.1 µm (or 100 nm), or PM 0.1. They are nanoparticles and their impact on human health is not yet clear.With more than 1.5 million employees, textiles and clothing is a diverse sector that plays an important role in the European manufacturing industry, producing a turnover of €162 billion.An important component of the solid particles that generate air pollution in the textile industry is microplastics (MP) and nano plastics (NP), which also include microfibers (<5mm) and nanofibers (<100 nm), respectively. The particles released into the air during fiber and yarn processing range from 1 µg/m3 to 50 µg/m3.The paper presents the results of the determination of indoor and outdoor air concentration levels in textile companies, to identify the areas with the highest concentration level, by using an online recording system such as the Laser Aerosol Spectrometer MINI LAS model 11-E. The total concentration level TSP (µg/m3), the fractions PM 10(µg/m3), PM 2.5(µg/m3), PM1(µg/m3), as well as the total number of particles TC (1/l), were shown. It was noted that TSP is approximately at the same level both indoors and outdoors, but the fractions of PM10, PM2.5, and PM1 have much higher values indoors than outdoors with possible consequences on workers' health.The next step was the collection of fibers, namely micro and nano plastic particles from the vicinity of the workplaces of polyester, polyamide, and polypropylene fibers processing units in the textile industry in Romania, to obtain a sufficient quantity for laboratory analysis to determine the size and shape of the particles as well as their chemical composition. Two types of pumps were used, differentiated by their operating parameters: TECORA SKYPOST with airflow of 38 l/min and GILAIRPLUS with airflow 2l/min. Filters made of different materials with different diameters and pore sizes were used, namely: quartz filters (ø 47 mm, and ø 37 mm) on a TECORA SKYPOST type pump, polycarbonate nucleopore coated with a gold membrane (ø 25 mm) and silica filter (ø 9 mm) on GILAIRPLUS type pump.Using descriptive statistics, the calculation of correlation coefficients highlighted a strong correlation between the variables: "Collected mass/ Air concentration" and "Collected mass/ Air volume" for all diameters of the filters.The highest collected particle volume, determined by weighing the filters before and after collection, was obtained with the quartz filters (ø 47 mm) at an airflow of 38 l/min. The particles collected (polyester, polyamide, polypropylene) in the first stage were analyzed by SEM and thermogravimetric and it was found that the quartz filters absorbed the particles inside, with very few remaining on the surface. Thus no known methods can be used to perform analysis for particles collected on quartz filters. The number of particles on the filters was insufficient for analysis either because of the collection parameters used or because of the loss of particles during transport. As a result, in the next step, the use of 9 mm Si filters using the GILAIRPLUS pump at an airflow rate of 2l/min was chosen.To improve the transport conditions and avoid the loss of the particles and keep them on the surface of the filters, two methods were applied:- after weighing the filters were reintroduced into the collection pump holder;- a filtration system for airborne micro-nano plastics was designed and manufactured to selectively collect and transport PM10 and PM1 particles collected on SI filters.In both cases, SEM, Raman mapping, and GS-MS microscopy were used for analysis.Several times more PM10 than PM1 (74.5µg compared to 12.5 µg) was found. In all cases, both particles and fibers showed the same Raman fingerprint.The GS-MS analyses showed some contamination of the workspaces with particles other than the processed fibers. The presence of non-notifiable substances was also observed.The most viable filters are Si filters with a pore size of 10 microns to 1 micron and the use of the selected collection and transport filter system. In the following a filter system will be applied for collection on Au membrane-coated polycarbonate filters.
T2 - 5th International Conference on Human Systems Engineering and Design: Future Trends and Applications (IHSED 2023)
KW - Microplastics
KW - Textiles
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624442
DO - https://doi.org/10.54941/ahfe1004132
VL - 112
SP - 212
EP - 223
PB - AHFE International
AN - OPUS4-62444
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hoque, Maroof Arshadul
A1 - Sommerfeld, Thomas
A1 - Lisec, Jan
A1 - Das, Prasenjit
A1 - Prinz, Carsten
A1 - Heinekamp, Christian
A1 - Stolar, Tomislav
A1 - Etter, Martin
A1 - Rosenberger, David
A1 - George, Janine
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
T1 - Mechanochemically Synthesized Covalent Organic Framework Effectively Captures PFAS Contaminants
N2 - Per‐ and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants that pose significant health risks, prompting urgent efforts to develop effective removal methods and adsorbers. Covalent organic frameworks (COFs) are metal‐free adsorbers with high stability and tunable porosity. A highly crystalline COF is synthesised mechanochemically using 1,3,5‐tris(4‐aminophenyl)benzene (TAPB) and 1,3,5‐triformylbenzene (TFB). The formation dynamics are monitored in real time with time‐resolved in situ synchrotron X‐ray diffraction. The TAPB‐TFB COF demonstrates good efficiency in eliminating PFAS from water. Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) are effectively extracted, and most of the adsorption occurred within the first 10 min. Additionally, X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and DFT calculations are employed to elucidate the molecular interactions between PFAS and the COF framework. The rapid and efficient removal of PFAS makes TAPB‐TFB COF a promising material for water treatment applications.
KW - COFs
KW - Ball-milling
KW - PFAS
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648712
DO - https://doi.org/10.1002/smll.202509275
SN - 1613-6810
VL - 21
IS - 44
SP - 1
EP - 8
PB - Wiley
CY - Weinheim
AN - OPUS4-64871
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Weidner, Steffen
T1 - MALDI Mass spectrometry of synthetic polymers – making molecular elephants to fly
N2 - The importance of MALDI TOF mass spectrometry for the analysis of synthetic polymers is shown and some specific issues influencing the analysis e.g. polymer mass dispersity, matrix and matrix homogeneity, nature of cations and end groups, sequence distribution are discussed by means of examples.
T2 - Merck Polymer Seminar
CY - Online meeting
DA - 29.04.2021
KW - MALDI-ToF MS
KW - Ionization
KW - Desorption
KW - Polymers
PY - 2021
AN - OPUS4-52545
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Li, Yue
A1 - Colnaghi, Timoteo
A1 - Gong, Yilun
A1 - Zhang, Huaide
A1 - Yu, Yuan
A1 - Wei, Ye
A1 - Gan, Bin
A1 - Song, Min
A1 - Marek, Andreas
A1 - Rampp, Markus
A1 - Zhang, Siyuan
A1 - Pei, Zongrui
A1 - Wuttig, Matthias
A1 - Ghosh, Sheuly
A1 - Körmann, Fritz
A1 - Neugebauer, Jörg
A1 - Wang, Zhangwei
A1 - Gault, Baptiste
T1 - Machine learning‐enabled tomographic imaging of chemical short‐range atomic ordering
N2 - In solids, chemical short‐range order (CSRO) refers to the self‐organization of atoms of certain species occupying specific crystal sites. CSRO is increasingly being envisaged as a lever to tailor the mechanical and functional properties of materials. Yet quantitative relationships between properties and the morphology, number density, and atomic configurations of CSRO domains remain elusive. Herein, it is showcased how machine learning‐enhanced atom probe tomography (APT) can mine the near‐atomically resolved APT data and jointly exploit the technique's high elemental sensitivity to provide a 3D quantitative analysis of CSRO in a CoCrNi medium‐entropy alloy. Multiple CSRO configurations are revealed, with their formation supported by state‐of‐the‐art Monte‐Carlo simulations. Quantitative analysis of these CSROs allows establishing relationships between processing parameters and physical properties. The unambiguous characterization of CSRO will help refine strategies for designing advanced materials by manipulating atomic‐scale architectures.
KW - Chemical short-range order (CSRO)
KW - Atom probe tomography (APT)
KW - Machine learning
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623777
DO - https://doi.org/10.1002/adma.202407564
SN - 1521-4095
VL - 36
IS - 44
SP - 1
EP - 9
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-62377
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Radtke, Martin
T1 - Machine learning: examples from BAMline
N2 - Various applications for artificial intelligence in the context of spectroscopy will be presented. in particular, examples from BAMline will be presented. After a short introduction to synchrotron radiation, artificial intelligence algorithms for the quantification of X-ray fluorescence measurement are discussed. In the second example, information retrieval by natural language processing is discussed.
T2 - Analytical Academy
CY - Online meeting
DA - 02.06.2020
KW - Machine learning
KW - BAMline
KW - XRF
KW - Synchrotron
PY - 2020
AN - OPUS4-51898
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Radtke, Martin
T1 - Machine learning for direct quantification of XRF measurements
N2 - In this talk I’ll describe the use of artificial neural networks (ANN) for quantifying X-ray fluorescence (XRF) measurements. The main idea of this talk is to give an overview of the process needed to generate a model that can then be applied to a specific problem.
In XRF, a sample is excited with X-rays and the resulting characteristic radiation is detected to determine elements quantitatively and qualitatively. This is traditionally done in several time-consuming steps. I’ll show the possibilities and problems of using a neural network to realise a "one-click" quantification. This includes generating training data using Monte Carlo simulation and augmenting the existing data set with an ANN to generate more data. The search for the optimal hyperparameters, manually and automatically, is also described. For the case presented, we were able to train a network with a mean absolute error of 0.1% by weight for the synthetic data and 0.7% by weight for a set of experimental data obtained with certified reference materials.
T2 - Seminar series: Artificial Intelligence applied to X-ray / synchrotron techniques
CY - Online meeting
DA - 24.06.2021
KW - Artificial intelligence
KW - Machine learning
KW - Synchrotron
KW - XRF
PY - 2021
AN - OPUS4-54140
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Radtke, Martin
A1 - Rakotondrajoa, A.
T1 - Machine learning based quantification of synchrotron radiation-induced X-ray fluorescence measurements - a case study
N2 - In this work, we describe the use of artificial neural networks for the quantification of X-ray fluorescence measurements. The training data were generated using Monte Carlo simulation, which avoided the use of adapted reference materials. The extension of the available data set by means of an ANN to generate additional data was demonstrated. Particular emphasis was put on the comparability of simulated and experimental data and how the influence of deviations can be reduced. The search for the optimal hyperparameter, manual and automatic, is also described. For the presented case, we were able to train a network with a mean absolute error of 0.1 weight percent for the synthetic data and 0.7 weight percent for a set of experimental data obtained with certified reference materials.
KW - Machine learning
KW - BAMline
KW - XRF
KW - Synchrotron
KW - Neural network
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519008
DO - https://doi.org/10.1088/2632-2153/abc9fb
SP - 1
EP - 16
PB - IOP Publishing
AN - OPUS4-51900
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Radtke, Martin
T1 - Machine learning - Examples from BAM Line
N2 - This talk explores applications of artificial intelligence in the field of spectroscopy, with a special focus on research conducted at BAMline. We begin with an overview of synchrotron radiation and its unique capabilities in material analysis. The first part of the talk will cover the integration of AI algorithms in quantifying X-ray fluorescence measurements, providing enhanced precision and efficiency in data analysis. Following this, we will examine the role of language models in spectroscopic research, showcasing how these tools can facilitate the control of complex experimental set-ups
T2 - Analytical Academy
CY - Berlin, Germany
DA - 12.11.2024
KW - ChatGPT
KW - Neural networks
KW - XRF
KW - Synchrotron
KW - BAMline
PY - 2024
AN - OPUS4-61698
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Dalgic, Mete-Sungur
T1 - Lösemittelfreie Probenpräparation zur Untersuchung von Polymerblends mittels MALDI-TOF MS
N2 - Die Probenpräparation ist ein wichtiger Schritt für die Qualität der Massenspektren in MALDI-TOF MS. Es werden Polymerproben, die lösungsmittelbasiert und lösungsmittelfrei präpariert worden sind, verglichen. Dabei werden die Intensitätsverhältnisse von ternären Mischungen von PEG-, PS- und PMMA-Polymeren beachtet.
T2 - 28. Kolloquium - Massenspektrometrische Techniken zur Untersuchung synthetischer Polymere
CY - Berlin, Germany
DA - 14.05.2024
KW - Polymere
KW - Massenspektrometrie
KW - Probenpräparation
PY - 2024
AN - OPUS4-60032
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kricheldorf, H.
A1 - Weidner, Steffen
T1 - Low Molar Mass Cyclic Poly(L-lactide)s: Separate Transesterification Reactions of Cycles and Linear Chains in the Solid State
N2 - L-Lactide (LA) was polymerized with neat tin(II) 2-ethylhexanoate (SnOct2) in toluene at 115 °C at low concentration with variation of the LA/Cat ratio. Cyclic polylactides (cPLAs) with number average molecular weights (Mn) between 7 000 and 17 000 were obtained. MALDI-TOF mass spectrometry also revealed the formation of a few percent of linear chains. Crystalline cPLAs with Mn around 9 000 and 14 000 were annealed at 140 °C in the presence of ScOct2 or dibutyl-2-stanna-1,3-dithiolane (DSTL). Simultaneously, crystallites of extended linear chains and crystallites of extended cycles were formed regardless of the catalyst, indicating that transesterification reaction proceeded different for linear chains and for cycles, governed by thermodynamic control. The formation of extended chain crystallites with low dispersity indicates the existence of symproportionation of short and long chains. A complementary experiment was carried out with a PLA ethyl ester composed mainly of linear chains with a small fraction of cycles
KW - Polylactide
KW - MALDI-TOF MS
KW - Annealing
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-606228
DO - https://doi.org/10.1039/D4SM00567H
SN - 1744-6848
SP - 1
EP - 12
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-60622
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - INPR
A1 - Morcillo, Dalia
A1 - Oelze, Marcus
A1 - Seena Prem, Pranav
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Emmerling, Franziska
A1 - Recknagel, Sebastian
A1 - Panne, Ulrich
A1 - Abad Andrade, Carlos Enrique
T1 - Lithium isotope fractionation as an early indicator of degradation mechanisms in lithium-ion batteries
N2 - Aging in lithium-ion batteries (LIBs) degrades performance and hinders sustainability, demanding advanced diagnostics for early failure prediction. We investigate lithium isotope fractionation (LIF) as an innovative probe of degradation in lithium cobalt oxide (LCO) coin cells aged over 0−700 cycles. High-precision multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) quantified δ7Li variations across cell stages: non-cycled (0 cycles), newly formed (5 cycles), semi-aged (250 cycles), and fully aged (700 cycles). During early cycling (≤ 45 cycles), chemical processes drive 7Li enrichment at the anode (δ7Li vs LSVEC = +12 ‰) through solid electrolyte interphase (SEI) formation, while the cathode depletes in 7Li (δ7Li vs LSVEC = −0.7 ‰). Beyond 45 cycles, electric field-induced migration predominates, promoting 6Li intercalation into the anode and increasing the δ7Li of the cathode by 8.1 ‰. Mass balance verifies isotope conservation, attributing shifts to redistribution and trapping. Complementary electrochemical impedance spectroscopy (EIS) and X-ray absorption spectroscopy and diffraction confirm SEI expansion, cobalt oxidation, lattice shrinkage, and changes in electrode structure, corroborating LIF trends. Notably, a δ7Li inflection at approximately 270 cycles anticipates end-of-life by 70 cycles, surpassing traditional methods in sensitivity. LIF emerges as a predictive indicator of aging mechanisms, informing optimized designs for durable LIBs.
KW - Lithium isotope fractionation
KW - Lithium-ion batteries
KW - Degradation mechanisms
KW - LiCoO2 cathodes
KW - LCO
KW - Isotopic tracing
KW - Lithium isotopes
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650945
DO - https://doi.org/10.26434/chemrxiv-2025-16lvq
SP - 1
EP - 19
AN - OPUS4-65094
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Rossi, A
T1 - Lactose Tablets as Suitable Microplastics Reference Material to Support Validation Studies and Quality Control
N2 - One of the main challenges in validating microplastics detection methods is the lack of suitable reference materials that accurately reflect the properties of interest. To bridge this gap, the EU-funded PlasticTrace project has developed water-soluble tablets containing precisely defined amounts of polyethylene terephthalate (PET) particles. Each tablet includes a specific mass (0.2, 18.5, or 400 µg) and particle count (151 or 1764, measured via Raman spectroscopy). Production follows a rigorous solid-phase dilution process, ensuring high reproducibility and quality control. The PET particles used in these tablets have an average size of approximately 40 µm, with a range between 10 and 200 µm, and an irregular, stone-like shape. All measurements align with ISO/TC 147/SC 2 standardization efforts and adhere to ISO/DIS 16094-2 and ISO/DIS 16094-3. To assess tablet homogeneity, the most widely accepted microplastics detection techniques, i.e. µ-FTIR, µ-Raman, Py-GC/MS, and TED-GC/MS, were applied. Different batches were produced, each containing varying particle numbers and masses, reaching the detection limits of the methods used. The results demonstrated excellent consistency between tablets, successfully passing homogeneity tests. Furthermore, no significant changes were observed in the tablets' composition or stability after six months of storage. This innovative reference material represents an important advancement in microplastics analysis, supporting laboratories in meeting EU Commission requirements for the monitoring of microplastics in drinking water and wastewater with greater accuracy and reliability. The production process can be transferred for other plastic particles is this size range.
T2 - BERM 16
CY - Halifax, Canada
DA - 01.06.2025
KW - Microplastics
KW - TED-GC/MS
KW - Reference materials
KW - Raman microscopy
PY - 2025
AN - OPUS4-63403
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rösler, Alexander
A1 - Weidner, Steffen
A1 - Klamroth, Tillmann
A1 - Müller, Axel H. E.
A1 - Schlaad, Helmut
T1 - Kinetics of anionic polymerization of β‐myrcene in hydrocarbon solvents
N2 - The kinetics of anionic polymerization of β‐myrcene initiated by sec‐butyllithium were examined in saturated and unsaturated hydrocarbon solvents, i.e. cyclohexane, cyclohexene, 4‐vinylcyclohexene and dl‐limonene. Polymerizations usually proceeded in a living manner, i.e. in the absence of termination and chain transfer reactions, in all solvents, to produce well‐defined polymyrcenes with high content (85%) of cis‐1,4 units. However, polymyrcenyllithium chains exhibited limited long‐term stability in 4‐vinylcyclohexene solution, most probably due to chain transfer to solvent. Reaction orders with respect to the concentration of active chains were found to be one‐quarter in cyclohexane increasing to one‐half in unsaturated solvents, indicating that the polymyrcenyllithium chains are present as tetrameric or dimeric associates, respectively. Apparent activation energies were found to be 81 kJ mol−1 in cyclohexane and 77 kJ mol−1 in dl‐limonene solution, which are close to the values obtained by quantum chemical calculations.
KW - MALDI-TOF MS
KW - Anionic polymerization
KW - β‐myrcene
KW - Kinetics
KW - Reaction order
KW - Activation energy
KW - Microstructure
KW - Quantum chemical calculations
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630900
DO - https://doi.org/10.1002/pi.6772
SN - 1097-0126
SP - 1
EP - 8
PB - Wiley
CY - New York, NY
AN - OPUS4-63090
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rösler, Alexander
A1 - Weidner, Steffen
A1 - Klamroth, Tillmann
A1 - Müller, Axel HE
A1 - Schlaad, Helmut
T1 - Kinetics of anionic polymerization of β‐myrcene in hydrocarbon solvents
N2 - AbstractThe kinetics of anionic polymerization of β‐myrcene initiated by sec‐butyllithium were examined in saturated and unsaturated hydrocarbon solvents, i.e. cyclohexane, cyclohexene, 4‐vinylcyclohexene and dl‐limonene. Polymerizations usually proceeded in a living manner, i.e. in the absence of termination and chain transfer reactions, in all solvents, to produce well‐defined polymyrcenes with high content (85%) of cis‐1,4 units. However, polymyrcenyllithium chains exhibited limited long‐term stability in 4‐vinylcyclohexene solution, most probably due to chain transfer to solvent. Reaction orders with respect to the concentration of active chains were found to be one‐quarter in cyclohexane increasing to one‐half in unsaturated solvents, indicating that the polymyrcenyllithium chains are present as tetrameric or dimeric associates, respectively. Apparent activation energies were found to be 81 kJ mol−1 in cyclohexane and 77 kJ mol−1 in dl‐limonene solution, which are close to the values obtained by quantum chemical calculations. © 2025 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
KW - Myrcene
KW - Anionic polymerization
KW - Reaction order
KW - Activation energy
KW - Microstructure
KW - Quantum chemical calculation
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-636840
DO - https://doi.org/10.1002/pi.6772
SN - 0959-8103
SP - 1
EP - 8
PB - Wiley
AN - OPUS4-63684
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rösler, Alexander
A1 - Weidner, Steffen
A1 - Klamroth, Tillmann
A1 - Müller, Axel HE
A1 - Schlaad, Helmut
T1 - Kinetics of anionic polymerization of β‐myrcene in hydrocarbon solvents
N2 - AbstractThe kinetics of anionic polymerization of β‐myrcene initiated by sec‐butyllithium were examined in saturated and unsaturated hydrocarbon solvents, i.e. cyclohexane, cyclohexene, 4‐vinylcyclohexene and dl‐limonene. Polymerizations usually proceeded in a living manner, i.e. in the absence of termination and chain transfer reactions, in all solvents, to produce well‐defined polymyrcenes with high content (85%) of cis‐1,4 units. However, polymyrcenyllithium chains exhibited limited long‐term stability in 4‐vinylcyclohexene solution, most probably due to chain transfer to solvent. Reaction orders with respect to the concentration of active chains were found to be one‐quarter in cyclohexane increasing to one‐half in unsaturated solvents, indicating that the polymyrcenyllithium chains are present as tetrameric or dimeric associates, respectively. Apparent activation energies were found to be 81 kJ mol−1 in cyclohexane and 77 kJ mol−1 in dl‐limonene solution, which are close to the values obtained by quantum chemical calculations. © 2025 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
KW - Myrcene
KW - Anionic polymerization
KW - MALDI TOF MS
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-649039
DO - https://doi.org/10.1002/pi.6772
SN - 0959-8103
SP - 1
EP - 8
PB - Wiley
AN - OPUS4-64903
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Margreiter, R.
A1 - Baumann, J.
A1 - Mantouvalou, I.
A1 - Radtke, Martin
A1 - Reinholz, Uwe
A1 - Strub, E.
T1 - Investigations on fire-gilding
N2 - Fire-gilding is a historic technique for the application of golden layers on a number of different base materials utilizing a gold amalgam. This technique leaves a significant amount of Hg in the golden layer, giving archeometrists a reliable indicator to identify firegildings.
Recent findings on presumably fire-gilded objects have shown in several cases significantly lower Hg content than previously studied objects. This prompted a synchrotron-based X-ray fluorescence investigation into the Hg distribution along the material–gilding interface, as well as a series of measurements regarding the Hg content development in fire-gilded samples during artificial aging. This work presents findings on laboratory-prepared fire-gildings, indicating an Hg enrichment at the interface of firegilded silver samples. Notably, such an enrichment is missing in fire-gilded copper samples. Further, it is confirmed that fire-gilded layers typically do not undercut an Hg bulk content of 5%. In this light, it seems improbable that ancient samples that contain <5% Hg are fire-gilded. The results presented in this study might lead to a non-destructive method to identify the Hg enrichment at the interface. This might be obtained by a combination of different non-destructive measurements and might also work unambiguously in samples in which the gold top layer is altered.
KW - BAMline
KW - X-Ray Fluorescence
KW - Gilding
KW - Depth profile
KW - Archaeometry
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552885
DO - https://doi.org/10.1111/arcm.12797
SN - 0003-813X
SP - 1
EP - 14
PB - Wiley online library
AN - OPUS4-55288
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lutz, C.
A1 - Hampel, S.
A1 - Beuermann, S.
A1 - Turek, T.
A1 - Kunz, U.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Radtke, Martin
A1 - Fittschen, U. E. A.
T1 - Investigation on Vanadium Species Distribution in Nafion™ 117 after Cyclization in a Vanadium Redox Flow Battery
N2 - The vanadium redox flow battery (VRFB) is currently a potential candidate for stationary energy storage. A major challenge is the unintended vanadium transport through the separator, which results in a fade of capacity. To overcome this issue, it is necessary to understand the transport processes in the membrane on a more fundamental level. In this work, the vanadium species distribution in Nafion™ 117 after cyclization was investigated. Two membranes, one from a charged VRFB and another from a discharged VRFB, were analyzed using ultraviolet–visible spectroscopy (UV/VIS) and X-ray absorption near edge structure spectroscopy (XANES). Little difference between the two membranes was recognizable according to the UV/VIS results. In comparison, the XANES results showed that the membrane from the charged VRFB contains more V3+ than VO2+, whereas for the discharged case, more VO2+ is present in the membrane.
KW - Synchrotron
KW - BAMline
KW - XANES
KW - Vanadium redox flow battery
PY - 2021
VL - 64
SP - 1
EP - 8
AN - OPUS4-54144
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Lutz, C.
T1 - Investigation on Vanadium Crossover in Nafion ™ and Novel PVDF Based Membranes for Vanadium Redox Flow Batteries
N2 - Vanadium redoxflow batteries (VRFB)are currently one of the most promising candidates for stationary energys torage.For large scale applications the ion conducting membranes currently in use need to be improved. Ideally,they need to become more cost efficient and selective regarding the vanadium crossover.For a better understanding of the vanadium crossover, the development of reliable analytical methods and procedures, that elucidate uptake and transport of vanadium ions in the membrane, is necessary. First, we present the uptake of V2+,V3+,VO2+, VO2+ and V2O33+ in Nafion™ and in a novel membrane based onpoly(1,1-difluoroethylene)(PVDF). In preliminary discharge/charge experiments the ETFE-based membrane, the precursor of PVDF-based membrane, performed comparable to Nafion™. The methods of choice for speciation are UV/Vis and X-ray absorption near edge structure spectroscopy (XANES). According to the results, V2O33+, formed from VO2+ and VO2+, diffuses also into the membrane. In present models, the diffusion of V2O33+ is neglected. In addition,we study whether reactions could take place inside the membranes’ nanoscopic water body using XANES. Exposing Nafion™ from one site with V3+a nd from the other site with VO2+ realized the experiment. The results verified that VO2+ was formed inside the membrane. However,in present models reactions inside the membrane are neglected, too.
T2 - Denver X-Ray Conference
CY - Online meeting
DA - 03.08.2020
KW - Batteries
KW - BAMline
KW - XANES
KW - VRF
PY - 2020
AN - OPUS4-51909
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Iro, M.
T1 - Investigation of the transmission properties of a polycapillary half-lens and their effect on quantification for confocal μXRF
N2 - Confocal Micro X-ray fluorescence analysis (μXRF) is a powerful method for the destruction-free investigation of the elemental composition of various samples in three dimensions. Quantitative results rely heavily on the transmission properties of polycapillary optics, used in confocal setups.
Different models for the functional correlation between energy and transmission of a polycapillary half-lens are compared with experimental data, established with a monochromatic confocal laboratory setup [1], as well as Monte-Carlo-Simulations [2]. The effect of the different approaches on quantitative results are compared using well known SRMs, ranging from thick samples to thin layers and structured materials.
Along with this the basic principles for quantitative evaluations of XRF spectra taken with confocal setups are presented, and compared with experimental results.
T2 - Denver X-Ray Conference
CY - Online meeting
DA - 02.08.2021
KW - Synchrotron
KW - BAMline
KW - Polycapillaries
PY - 2021
AN - OPUS4-54143
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Marquardt, Julien
T1 - Investigating the morphology of nanostructured mixed metal oxides (Ir/TiOx) and its impact on the electrocatalytic OER-activity
N2 - The electrocatalytic conversion of water into molecular hydrogen and oxygen under the utilization of excess renewable energies, such as wind power, photovoltaics and hydroelectric power is one possible pathway to establish a sustainable hydrogen economy. The obtained hydrogen is either stored and used in a fuel cell or consumed on-site in industrial applications.
Water electrolysis systems (WES) are based on two half cell reactions, such as oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) which both proceed simultaneously. The OER suffers from slow reaction kinetics and thus limits the overall performance.
The most promising compounds in acidic electrolysis are IrO2 and RuO2. Due to their rare abundance and extremely high price a wide use of acidic WES was prevented. Lowering the catalysts noble metal content by mixing iridium with titanium reduces the production costs.
Thin films are produced by dip coating a solution of metal oxide precursors alongside with a polymer template dissolved in ethanol. The obtained samples are subsequently calcined to the remove the template and adjust crystallinity. Finally, an additional iridium deposition step was performed on the outer surface plane area.
Understanding the influence of structural and morphological aspects on the OER-activity is beneficial to further optimize WES. The current presentation will thus give detailed insights to structural aspects obtained by Raman spectroscopy, small- and wide-angle X-ray scattering which are then combined with electrochemical parameters to deduce structure-activity relationships.
T2 - Joint Polish-German Crystallographic Meeting 2020
CY - Wrocław, Poland
DA - 24.02.2020
KW - nanostructured
KW - electrocatalysis
PY - 2020
AN - OPUS4-50664
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -