TY - JOUR
A1 - Müller, Birgit
A1 - Danielak, M.
A1 - Horn, Wolfgang
A1 - Jann, Oliver
A1 - Müller, D.
A1 - Panaskova, J.
A1 - Plehn, W.
T1 - Sensorische Bewertung der Emissionen aus Bauprodukten
N2 - Die Bewertung von VOC-Emissionen aus Bauprodukten soll durch das AgBB-Schema vereinheitlicht werden und eine gesundheitsrelevante Komponente enthalten. Das Deutsche Institut für Bautechnik (DIBt) hat das AgBB-Schema in weiten Teilen für seine Grundsätze zur gesundheitlichen Bewertung von Bauprodukten in Innenräumen implementiert. Neben der üblichen chemischen Emissionsmessung soll auch der Geruch für die Bewertung des Produkts herangezogen werden. Um den Geruch als festen Bestandteil in die Produktprüfung zu integrieren, wurden vom Umweltbundesamt zwei Vorhaben initiiert. Erste Ergebnisse des zweiten Vorhabens (FKZ 37 07 62 300; Sensorische Bewertung der Emissionen aus Bauprodukten Integration in die Vergabegrundlagen für den Blauen Engel und das Bewertungsschema des Ausschusses zur gesundheitlichen Bewertung von Bauprodukten) werden hier dargestellt.
KW - AgBB-Schema
KW - VOC
KW - Emissionen
KW - Geruch
KW - Bauprodukte
KW - Bewertung Emissionen
PY - 2009
SN - 0949-8036
SN - 0039-0771
SN - 1436-4891
VL - 69
IS - 6
SP - 246
EP - 250
PB - Springer-VDI-Verl.
CY - Düsseldorf
AN - OPUS4-19658
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Faghani, A.
A1 - Gholami, M. F.
A1 - Trunk, M.
A1 - Müller, J.
A1 - Pachfule, P.
A1 - Vogl, S.
A1 - Donskyi, Ievgen
A1 - Li, M.
A1 - Nickl, Philip
A1 - Shao, J.
A1 - Huang, M. R. S.
A1 - Unger, Wolfgang
A1 - Arenal, R.
A1 - Koch, C. T.
A1 - Paulus, B.
A1 - Rabe, J. P.
A1 - Thomas, A.
A1 - Haag, R.
A1 - Adeli, M.
T1 - Metal-Assisted and Solvent-Mediated Synthesis of Two-Dimensional Triazine Structures on Gram Scale
N2 - Covalent triazine frameworks are an emerging material class that have shown promising performance for a range of applications. In this work, we report on a metal-assisted and solvent-mediated reaction between calcium carbide and cyanuric chloride, as cheap and commercially available precursors, to synthesize two-dimensional triazine structures (2DTSs). The reaction between the solvent, dimethylformamide, and cyanuric chloride was promoted by calcium carbide and resulted in dimethylamino-s-triazine intermediates, which in turn undergo nucleophilic substitutions. This reaction was directed into two dimensions by calcium ions derived from calcium carbide and induced the formation of 2DTSs. The role of calcium ions to direct the two-dimensionality of the final structure was simulated using DFT and further proven by synthesizing molecular intermediates. The water content of the reaction medium was found to be a crucial factor that affected the structure of the products dramatically. While 2DTSs were obtained under anhydrous conditions, a mixture of graphitic material/2DTSs or only graphitic material (GM) was obtained in aqueous solutions. Due to the straightforward and gram-scale synthesis of 2DTSs, as well as their photothermal and photodynamic properties, they are promising materials for a wide range of future applications, including bacteria and virus incapacitation.
KW - XPS
KW - Triazine
KW - 2D
PY - 2020
DO - https://doi.org/10.1021/jacs.0c02399
VL - 142
IS - 30
SP - 12976
EP - 12986
PB - ACS American Chemical Society
AN - OPUS4-51203
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Seah, M.P.
A1 - Spencer, S.J.
A1 - Bensebaa, F.
A1 - Vickridge, I.
A1 - Danzebrink, H.
A1 - Krumrey, M.
A1 - Gross, Thomas
A1 - Österle, Werner
A1 - Wendler, E.
A1 - Rheinländer, B.
A1 - Azuma, Y.
A1 - Kojima, I.
A1 - Suzuki, N.
A1 - Suzuki, M.
A1 - Tanuma, S.
A1 - Moon, D.W.
A1 - Lee, H.J.
A1 - Cho, H.M.
A1 - Chen, H.Y.
A1 - Wee, A. T. S.
A1 - Osipowicz, T.
A1 - Pan, J.S.
A1 - Jordaan, W.A.
A1 - Hauert, R.
A1 - Klotz, U.
A1 - van der Marel, C.
A1 - Verheijen, M.
A1 - Tamminga, Y.
A1 - Jeynes, C.
A1 - Bailey, P.
A1 - Biswas, S.
A1 - Falke, U.
A1 - Nguyen, N.V.
A1 - Chandler-Horowitz, D.
A1 - Ehrstein, J.R.
A1 - Muller, D.
A1 - Dura, J.A.
T1 - Critical review of the current status of thickness measurements for ultrathin SiO2 on Si - Part V: Results of a CCQM pilot study
N2 - Results are reported from a pilot study under the Consultative Committee for Amount of Substance (CCQM) to compare measurements of and resolve any relevant measurement issues in, the amount of thermal SiO2 oxide on (100) and (111) orientation Si wafer substrates in the thickness range 1.5 - 8 nm. As a result of the invitation to participate in this activity, 45 sets of measurements have been made in different laboratories using 10 analytical methods: medium-energy ion scattering spectrometry (MEIS), nuclear reaction analysis (NRA), RBS, elastic backscattering spectrometry (EBS), XPS, SIMS, ellipsometry, grazing-incidence x-ray reflectrometry (GIXRR), neutron reflectometry and transmission electron microscopy (TEM). The measurements are made on separate sets of 10 carefully prepared samples, all of which have been characterised by a combination of ellipsometry and XPS using carefully established reference conditions and reference parameters.
The results have been assessed against the National Physical Laboratory (NPL) data and all show excellent linearity. The remaining data sets correlate with the NPL data with average root-mean-square scatters of 0.15 nm, half being better than 0.1 nm and a few at or better than 0.05 nm. Each set of data allows a relative scaling constant and a zero thickness offset to be determined. Each method has an inherent zero thickness offset between 0 nm and 1 nm and it is these offsets, measured here for the first time, that have caused many problems in the past. There are three basic classes of offset: water and carbonadeous contamination equivalent to ~1 nm as seen by ellipsometry; adsorbed oxygen mainly from water at an equivalent thickness of 0.5 nm as seen by MEIS, NRA, RBS and possibly GIXRR; and no offset as seen by XPS using the Si 2p peaks. Each technique has a different uncertainty for the scaling constant and consistent results have been achieved. X-Ray photoelectron spectroscopy has large uncertainties for the scaling constant but a high precision and, critically, if used correctly, has zero offset. Thus, a combination of XPS and the other methods allows the XPS scaling constant to be determined with low uncertainty, traceable via the other methods. XPS laboratories returning results early were invited to test a new reference procedure. All showed very significant improvements. The reference attenuation lengths thus need scaling by 0.986 ± 0.009 (at an expansion factor of 2) deduced from the data for the other methods. Several other methods have small offsets and, to the extent that these can be shown to be constant or measurable, then these methods will also show low uncertainty. Recommendations are provided for parameters for XPS, MEIS, RBS and NRA to improve their accuracy.
KW - Calibration
KW - Ellipsometry
KW - GIXRR
KW - Interlaboratory study
KW - MEIS
KW - Neutron reflectometry
KW - NRA
KW - RBS
KW - Silicon dioxide
KW - SIMS
KW - XPS
PY - 2004
DO - https://doi.org/10.1002/sia.1909
SN - 0142-2421
SN - 1096-9918
VL - 36
IS - 9
SP - 1269
EP - 1303
PB - Wiley
CY - Chichester
AN - OPUS4-5549
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mouiya, M.
A1 - Martynyuk, M.
A1 - Kupsch, Andreas
A1 - Laquai, R.
A1 - Müller, Bernd R.
A1 - Doyen, N.T.
A1 - Tamraoui, Y.
A1 - Serrano-Munoz, Itziar
A1 - Huger, M.
A1 - Kachanov, M.
A1 - Bruno, Giovanni
T1 - The stress–strain behavior of refractory microcracked aluminum titanate: The effect of zigzag microcracks and its modeling
N2 - The stress–strain behavior of ceramics, such as aluminum titanate, has certain features that are unusual for brittle materials—in particular, a substantial nonlinearity under uniaxial tension, and load–unload hysteresis caused by the sharp increase of the incremental stiffness at the beginning of unloading. These features are observed experimentally and are attributed to microcracking. Here we compare different degrees of stress–strain nonlinearity of aluminum titanate materials and quantitatively model them. We use advanced mechanical testing to observe the mechanical response at room and high temperature; electron microscopy, and X-ray refraction radiography to observe the microstructural changes. Experiments show that two types of microcracks can be distinguished: (i) microcracks induced by cooling from the sintering temperature (due to heterogeneity and anisotropy of thermal expansion), with typical sizes of the order of grain size, and (ii) much larger microcracks generated by the mechanical loading. The two microcrack types produce different effects on the stress–strain curves. Such microcracks and the features of the stress–strain behavior depend on the density of the cooling-induced microcracks and on the distribution of grain sizes. They are modeled analytically and numerically.
KW - Hystersis
KW - Nonlinear stress-strain curve
KW - Refractory
KW - Stiffness
KW - X-ray refraction
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580517
DO - https://doi.org/10.1111/jace.19325
SN - 1551-2916
VL - 106
SP - 6995
EP - 7008
PB - Wiley-Blackwell
CY - Oxford [u.a.]
AN - OPUS4-58051
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sieber, M. J.
A1 - Wilke, M.
A1 - Appelt, O.
A1 - Oelze, Marcus
A1 - Koch-Müller, M.
T1 - Melting relations of Ca–Mg carbonates and trace element signature of carbonate melts up to 9 GPa – A proxy for melting of carbonated mantle lithologies
N2 - The most profound consequences of the presence of Ca–Mg carbonates (CaCO3–MgCO3) in the Earth’s upper mantle may be to lower the melting temperatures of the mantle and control the melt composition.
Low-degree partial melting of a carbonate-bearing mantle produces CO2-rich, silica-poor melts compositionally imposed by the melting relations of carbonates. Thus, understanding the melting relations in the CaCO3–MgCO3 system facilitates the interpretation of natural carbonate-bearing silicate systems.
We report the melting relations of the CaCO3–MgCO3 system and the partition coefficient of trace elements between carbonates and carbonate melt from experiments at high pressure (6 and 9 GPa) and temperature (1300–1800 ◦C) using a rocking multi-anvil press. In the absence of water, Ca–Mg carbonates are stable along geothermal gradients typical of subducting slabs. Ca–Mg carbonates (∼ Mg0.1–0.9Ca0.9–0.1CO3) partially melt beneath mid-ocean ridges and in plume settings. Ca–Mg carbonates melt incongruently, forming periclase crystals and carbonate melt between 4 and 9 GPa. Furthermore, we show that the rare earth element (REE) signature of Group-I kimberlites, namely strong REE fractionation and depletion of heavy REE relative to the primitive mantle, is resembled by carbonate melt in equilibrium with Ca-bearing magnesite and periclase at 6 and 9 GPa. This suggests that the dolomite–magnesite join of the CaCO3–MgCO3 system might be useful to approximate the REE signature of carbonate-rich melts parental to kimberlites.
KW - High pressure experiments
KW - Laser Ablation
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561197
DO - https://doi.org/10.5194/ejm-34-411-2022
SN - 0935-1221
VL - 34
IS - 5
SP - 411
EP - 424
PB - Copernicus Publications
CY - Göttingen
AN - OPUS4-56119
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, Anja
A1 - Heinrich, Thomas
A1 - Tougaard, S.
A1 - Werner, W. S. M.
A1 - Hronek, M.
A1 - Kunz, Valentin
A1 - Radnik, Jörg
A1 - Stockmann, Jörg M.
A1 - Hodoroaba, Vasile-Dan
A1 - Benemann, Sigrid
A1 - Nirmalananthan-Budau, Nithiya
A1 - Geißler, Daniel
A1 - Sparnacci, K.
A1 - Unger, Wolfgang
T1 - Determining the thickness and completeness of the shell of polymer core-shell nanoparticles by X-ray photoelectron spectroscopy, secondary ion mass spectrometry, and transmission scanning electron microscopy
N2 - Core–shell nanoparticles (CSNPs) have become indispensable in various industrial applications. However, their real internal structure usually deviates from an ideal core–shell structure. To control how the particles perform with regard to their specific applications, characterization techniques are required that can distinguish an ideal from a nonideal morphology. In this work, we investigated poly(tetrafluoroethylene)–poly(methyl methacrylate) (PTFE–PMMA) and poly(tetrafluoroethylene)–polystyrene (PTFE–PS) polymer CSNPs with a constant core diameter (45 nm) but varying shell thicknesses (4–50 nm). As confirmed by transmission scanning electron microscopy (T-SEM), the shell completely covers the core for the PTFE–PMMA nanoparticles, while the encapsulation of the core by the shell material is incomplete for the PTFE–PS nanoparticles. X-ray photoelectron spectroscopy (XPS) was applied to determine the shell thickness of the nanoparticles. The software SESSA v2.0 was used to analyze the intensities of the elastic peaks, and the QUASES software package was employed to evaluate the shape of the inelastic background in the XPS survey spectra. For the first time, nanoparticle shell thicknesses are presented, which are exclusively based on the analysis of the XPS inelastic background. Furthermore, principal component analysis (PCA)-assisted time-of-flight secondary-ion mass spectrometry (ToF-SIMS) of the PTFE–PS nanoparticle sample set revealed a systematic variation among the samples and, thus, confirmed the incomplete encapsulation of the core by the shell material. As opposed to that, no variation is observed in the PCA score plots of the PTFE–PMMA nanoparticle sample set. Consequently, the complete coverage of the core by the shell material is proved by ToF-SIMS with a certainty that cannot be achieved by XPS and T-SEM.
KW - XPS
KW - T-SEM
KW - ToF-SIMS
KW - Core-shell nanoparticles
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-499165
DO - https://doi.org/10.1021/acs.jpcc.9b09258
VL - 123
IS - 49
SP - 29765
EP - 29775
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-49916
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schartel, Bernhard
A1 - Perret, Birgit
A1 - Dittrich, Bettina
A1 - Ciesielski, M.
A1 - Krämer, J.
A1 - Müller, P.
A1 - Altstädt, V.
A1 - Zang, L.
A1 - Döring, M.
T1 - Flame retardancy of polymers: the role of specific reactions in the condensed phase
N2 - Condensed-phase mechanisms play a major role in fire-retardant polymers. Generations of development have followed the concept of charring to improve fire properties. Whereas the principal reactions are believed to be known, the specific description for multicomponent systems is lacking, as is the picture across different systems. A two-step approach is proposed in general, and also presented in greater detail. The second step covers the specific reactions controlling charring, whereas the actual reactants are provided in the preceding step. This model consistently incorporates the variety of structureproperty relationships reported. A comprehensive case study is presented on seven phosphorus flame retardants in two epoxy resins to breathe life into the two-step approach.
KW - Charring
KW - Epoxy
KW - Flame retardancy
KW - Pyrolysis
KW - Thermogravimetric analysis (TGA)
PY - 2016
DO - https://doi.org/10.1002/mame.201500250
SN - 1438-7492
SN - 1439-2054
VL - 301
IS - 1
SP - 9
EP - 35
PB - Wiley-VCH Verl.
CY - Weinheim
AN - OPUS4-35273
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tschöke, K.
A1 - Müller, I.
A1 - Memmolo, V.
A1 - Moix-Bonet, M.
A1 - Moll, J.
A1 - Lugovtsova, Yevgeniya
A1 - Golub, M.
A1 - Sridaran Venkat, R.
A1 - Schubert, L.
T1 - Feasibility of Model-Assisted Probability of Detection Principles for Structural Health Monitoring Systems based on Guided Waves for Fibre-Reinforced Composites
N2 - In many industrial sectors, Structural Health Monitoring (SHM) is considered as an addition to Non-Destructive Testing (NDT) that can reduce maintenance effort during lifetime of a technical facility, structural component or vehicle. A large number of SHM methods is based on ultrasonic waves, whose properties change depending on structural health. However, the wide application of SHM systems is limited due to the lack of suitable methods to assess their reliability. The evaluation of the system performance usually refers to the determination of the Probability of Detection (POD) of a test procedure. Up to now, only few limited methods exist to evaluate the POD of SHM systems, which prevent them from being standardised and widely accepted in industry. The biggest hurdle concerning the POD calculation is the large amount of samples needed. A POD analysis requires data from numerous identical structures with integrated SHM systems. Each structure is then damaged at different locations and with various degrees of severity. All of this is connected to high costs. Therefore, one possible way to tackle this problem is to perform computer-aided investigations. In this work, the POD assessment procedure established in NDT according to the Berens model is adapted to guided wave-based SHM systems. The approach implemented here is based on solely computer-aided investigations. After efficient modelling of wave propagation phenomena across an automotive component made of a carbon fibre-reinforced composite, the POD curves are extracted. Finally, the novel concept of a POD map is introduced to look into the effect of damage position on system reliability.
KW - Reliability
KW - Acoustics
KW - Monitoring
KW - Automotive engineering
KW - Elastodynamic Finite Inegration Technique
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528218
DO - https://doi.org/10.1109/TUFFC.2021.3084898
VL - 68
IS - 10
SP - 3156
EP - 3173
AN - OPUS4-52821
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Balzer, M.
A1 - Fenker, M.
A1 - Kappl, H.
A1 - Müller, Thoralf
A1 - Heyn, A.
A1 - Heiss, A.
A1 - Richter, A.
T1 - Corrosion protection of steel substrates by magnetron sputtered TiMgN hard coatings: Structure, mechanical properties and growth defect related salt spray test results
N2 - Hard and wear resistant coatings deposited by PVD techniques have been characterized for decades for their capabilities to protect steel substrates from corrosion. In the present work the effect of Mg incorporated into TiN coatings is described in terms of the corrosion behavior as well as the mechanical and structural properties.
TiN and TiMgN films with Mg contents between 10 and 35 at.% were deposited onto mirror polished 100Cr6 (1.3505) steel samples with 2.5 and 5 μm thickness by using DC magnetron sputtering. The corrosion protection capabilities of the coatings were characterized by neutral salt spray (NSS) test, considering the amounts and sizes of growth defects inherent in each coated sample as determined by a recently developed optical scan method (Large Area High Resolution mapping). The defect data were statistically analyzed for improved interpretation of NSS test results. Chosen growth defects were additionally analyzed by focused ion beam technique. Furthermore the coating composition and morphology, the hardness and the tribological behavior were characterized.
Polished steel samples coated with 2.5 μm TiMgN containing about 35 at.% Mg were in the plane free of corrosion after 24 h in a NSS test. TiMgN with 10 or 20 at.% Mg only provided a slightly improved corrosion protection in relation to pure TiN coatings, which was limited to certain types of growth defects. The highest Mg containing coatings exhibited a decreased hardness down to 1200 or 1800 HV depending on type of deposition (HV 1200: Ti- and Mg-target with rotating substrate holder, 1800: Mg-plugged Ti-target with static substrate holder), but also showed a strongly improved wear resistance against Al2O3 related to pure TiN. By analyzing the NSS test results it was found that the corrosion behavior of the coated samples did not only depend strongly on the Mg content, but also on the sample individual defect concentrations. Therefore this subject is extensively discussed.
KW - Physical vapour deposition (PVD)
KW - Corrosion
KW - Growth defects
KW - Pinholes
KW - Magnesium
KW - TiMgN
PY - 2018
DO - https://doi.org/10.1016/j.surfcoat.2018.05.037
SN - 0257-8972
VL - 349
IS - 9
SP - 82
EP - 92
PB - Elsevier B.V.
AN - OPUS4-45712
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Abou-Ras, D.
A1 - Caballero, R.
A1 - Fischer, C.-H.
A1 - Kaufmann, C.A.
A1 - Lauermann, I.
A1 - Mainz, R.
A1 - Mönig, H.
A1 - Schöpke, A.
A1 - Stephan, C.
A1 - Streeck, C.
A1 - Schorr, S.
A1 - Eicke, A.
A1 - Döbeli, M.
A1 - Gade, B.
A1 - Hinrichs, J.
A1 - Nunney, T.
A1 - Dijkstra, H.
A1 - Hoffmann, V.
A1 - Klemm, D.
A1 - Efimova, V.
A1 - Bergmaier, A.
A1 - Dollinger, G.
A1 - Wirth, Thomas
A1 - Unger, Wolfgang
A1 - Rockett, A.A.
A1 - Perez-Rodriguez, A.
A1 - Alvarez-Garcia, J.
A1 - Izquierdo-Roca, V.
A1 - Schmid, T.
A1 - Choi, P.-P.
A1 - Müller, M.
A1 - Bertram, F.
A1 - Christen, J.
A1 - Khatri, H.
A1 - Collins, R.W.
A1 - Marsillac, S.
A1 - Kötschau, I.
T1 - Comprehensive comparison of various techniques for the analysis of elemental distributions in thin films
N2 - The present work shows results on elemental distribution analyses in Cu(In,Ga)Se2 thin films for solar cells performed by use of wavelength-dispersive and energy-dispersive X-ray spectrometry (EDX) in a scanning electron microscope, EDX in a transmission electron microscope, X-ray photoelectron, angle-dependent soft X-ray emission, secondary ion-mass (SIMS), time-of-flight SIMS, sputtered neutral mass, glow-discharge optical emission and glow-discharge mass, Auger electron, and Rutherford backscattering spectrometry, by use of scanning Auger electron microscopy, Raman depth profiling, and Raman mapping, as well as by use of elastic recoil detection analysis, grazing-incidence X-ray and electron backscatter diffraction, and grazing-incidence X-ray fluorescence analysis. The Cu(In,Ga)Se2 thin films used for the present comparison were produced during the same identical deposition run and exhibit thicknesses of about 2 µm. The analysis techniques were compared with respect to their spatial and depth resolutions, measuring speeds, availabilities, and detection limits.
KW - Elemental distributions
KW - Comparison
KW - Depth profiling
KW - Chemical mapping
KW - Thin films
KW - Solar cells
KW - Chalcopyrite-type
KW - Cu(In,Ga)Se2
PY - 2011
DO - https://doi.org/10.1017/S1431927611000523
SN - 1431-9276
SN - 1435-8115
VL - 17
IS - 5
SP - 728
EP - 751
PB - Cambridge University Press
CY - New York, NY
AN - OPUS4-24506
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kotaka, M.
A1 - Honma, T.
A1 - Komatsu, T.
A1 - Shinozaki, K.
A1 - Affatigato, M.
A1 - Müller, Ralf
T1 - Control of self-powdering phenomenon in ferroelastic β′-Gd2(MoO4)3 crystallization in boro-tellurite glasses
N2 - Glasses with compositions of 21Gd2O3-63MoO3-(16-x)B2O3-xTeO2 (mol%) (x= 0, 2, 4, 8) were prepared using a conventional melt quenching technique, and the crystallization behavior of ferroelastic β′-Gd2 MoO4)3 Crystals was examined to clarify the mechanism of self-powdering phenomenon and to design bulk crystallized glasses. It was found that the self-powdering phenomenon appeared significantly during the crystallization at temperatures near the crystallization peak temperature, but the phenomenon is suppressed in the crystallization at temperatures much higher than the glass transition temperature. It was also found that the substitution of TeO2 for B2O3 in the base glasses suppresses the self-powdering phenomenon and consequently bulk crystallized glasses were obtained in the glass with x=8 mol%. The densities at room temperature of the base glasses are d =4.755–4.906 g/cm3, being much higher than the value of d=4.555 g/cm3 for β′-Gd2(MoO4)3 crystal. It is proposed that the stresses in the inside of crystals induced by large density differences (i.e., large molar volume differences) between the glassy phase and crystals might be relaxed effectively in the glasses containing TeO2 with weak TeeO bonds and fragile character.
KW - Glass crystallization stress
PY - 2018
DO - https://doi.org/10.1016/j.jnoncrysol.2017.12.006
SN - 0022-3093
SN - 1873-4812
VL - 501
SP - 85
EP - 92
PB - Elsevier B.V.
AN - OPUS4-46472
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Niederleithinger, Ernst
A1 - Wang, Xin
A1 - Herbrand, M.
A1 - Müller, M.
T1 - Processing ultrasonic data by coda wave interferometry to monitor load tests of concrete beams
N2 - Ultrasonic transmission measurements have been used for decades to monitor concrete elements, mostly on a laboratory scale. Recently, coda wave interferometry (CWI), a technique adapted from seismology, was introduced to civil engineering experiments. It can be used to reveal subtle changes in concrete laboratory samples and even large structural elements without having a transducer directly at the place where the change is taking place. Here, several load tests until failure on large posttensioned concrete beams have been monitored using networks of embedded transducers. To detect subtle effects at the beginning of the experiments and cope with severe changes due to cracking close to failure, the coda wave interferometry procedures had to be modified to an adapted step-wise approach. Using this methodology, we were able to monitor stress distribution and localize large cracks by a relatively simple technique. Implementation of this approach on selected real structures might help to make decisions in infrastructure asset management.
KW - Ultrasound
KW - Concrete
KW - Monitoring
KW - Coda wave interferometry
KW - Embedded transducers
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-452328
DO - https://doi.org/10.3390/s19010147
SN - 1424-8220
VL - 19
IS - 1
SP - Article 147, 1
EP - 13
PB - MDPI
CY - Basel
AN - OPUS4-45232
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Niederleithinger, Ernst
A1 - Herbrand, M.
A1 - Müller, M.
T1 - Monitoring von Querkraftversuchen an Spannbetondurchlaufträgern mit Ultraschall und Codawelleninterferometrie
T1 - Monitoring of shear tests on prestressed concrete continuous beams using ultrasound and coda wave interferometry
N2 - Zusammenfassung Im Rahmen eines Forschungsvorhabens an der RWTH Aachen wurden mehrere Spannbetondurchlaufträger bis zum Versagen belastetet. Neben umfangreicher konventioneller Messtechnik wurden zusätzlich innovative Messmethoden durch die Bundesanstalt für Materialforschung und –prüfung (BAM) getestet. Darunter waren eingebettete Ultraschall-Transducer, deren Daten mit einer neuartigen Methode, der Codawelleninterferometrie (CWI), ausgewertet wurden. Dieses Verfahren detektiert auch kleinste Änderungen im Signal und in der Wellengeschwindigkeit gegenüber einer Referenzmessung. Hiermit können Belastungs- und Strukturänderungen sowie Schäden sehr viel sensibler angezeigt werden als bei konventionellen Ultraschallmessungen. Durch eine Modifikation des Verfahrens mit gleitender Referenz können aber auch starke Veränderungen im Material, wie sie bei Bruchversuchen auftreten, erfasst werden. In den Versuchen gelang es mit Netzwerken aus bis zu 20 Ultraschall-Transducern, Spannungskonzentrationen und Rissbildungen qualitativ zu detektieren und zu verfolgen, ohne dass die Sensoren direkt am Ort der Änderung angebracht sein müssen.
N2 - Abstract In the framework of a research project at RWTH Aachen University, a set of large scale post-tensioned concrete continuous beams has been loaded until failure. In addition to conventional measurement techniques, innovative methods like embedded ultrasonic transducers have been applied by the Bundesanstalt für Materialforschung und -prüfung (BAM). The data acquired with theses transducers has been processed with a novel method called coda wave interferometry (CWI). This technique is able to detect even very small changes in the ultrasonic signal and in wave velocity. Loads or structural changes as well as damages can be detected with a much higher sensitivity compared to conventional measurements. Using a modification of the technique with step-wise referencing larger changes in the material can be followed as well. In the experiments, networks of up to 20 ultrasonic transducers have been used. Stress concentrations and crack formation have been detected and monitored qualitatively, without having to place the transducers directly at the place of interest.
KW - Ultraschall
KW - Codawelleninterferometrie
KW - Brücken
KW - Belastung
KW - Monitoring
PY - 2017
SN - 0005-6650
SN - 1436-4867
VL - 92
IS - November
SP - 474
EP - 481
PB - Springer
CY - Düsseldorf
AN - OPUS4-42677
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dal Molin, E. S.
A1 - Henning, L. M.
A1 - Müller, J. T.
A1 - Smales, Glen Jacob
A1 - Pauw, Brian Richard
A1 - Bekheet, M. F.
A1 - Gurlo, A.
A1 - Simon, U.
T1 - Robocasting of ordered mesoporous silica‐based monoliths: Rheological, textural, and mechanical characterization
N2 - Hierarchically porous, high‐surface‐area silica materials are excellent candidates for multiple applications like catalysis and environmental remediation. Shaping these materials with additive manufacturing (AM) techniques, like robocasting, could enable their use with the benefit of on‐demand, customized shaping and maximizing performance. Herein, ordered mesoporous silica COK‐12 slurries were robocasted into monoliths, containing different ratios of uncalcined COK‐12 and sodium bentonite (0–25 wt.%). The rheology of the mixed slurries is characterized by lower flow indexes (0.69 vs. 0.32) and higher yield stresses (96 vs. 259 Pa) compared to pure COK‐12 ones. Monoliths were printed in woodpile structures and calcined at 600°C. Micro‐CT measurements showed a linear shrinkage of 25% after calcination. Mechanical characterization showed increased uniaxial strength (0.20 ± 0.07 to 1.0 ± 0.3 MPa) with increasing binder/solids ratio from 13 to 25%. The amorphous, mesoporous structure of COK‐12 was retained. The structures exhibited open porosities of 52 ± 4% and showed higher specific mesopore volumes, and increased average mesopore size (6 vs. 8 nm) compared to COK‐12. Small‐angle x‐ray scattering analysis revealed an increased lattice parameter (10.3 vs. 11.0 nm) and reduced wall thickness (3.1 nm vs. 4.1 nm) of the COK‐12 in the monoliths. These properties indicate suitability for their application as porous supports and adsorbents.
KW - Industrial and Manufacturing Engineering
KW - Additive manufacturing
KW - OMS
KW - Porous materials
KW - Robocasting
KW - X-ray scattering
KW - MOUSE
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582503
DO - https://doi.org/10.1002/nano.202300109
VL - 4
IS - 11-12
SP - 615
EP - 631
PB - Wiley-VCH GmbH
AN - OPUS4-58250
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Deubener, J.
A1 - Allix, M.
A1 - Davis, M.J.
A1 - Duran, A.
A1 - Höche, T.
A1 - Honma, T.
A1 - Komatsu, T.
A1 - Krüger, S.
A1 - Mitra, I.
A1 - Müller, Ralf
A1 - Nakane, S.
A1 - Pascual, M.J.
A1 - Schmelzer, J.W.
A1 - Zanotto, E.D.
A1 - Zhou, S.
T1 - Updated definition of glass-ceramics
N2 - Glass-ceramics are noted for their unusual combination of properties and manifold commercialized products for consumer and specialized markets. Evolution of novel glass and ceramic processing routes, a plethora of new compositions, and unique exotic nano- and microstructures over the past 60 years led us to review the Definition of glass-ceramics. Well-established and emerging processing methods, such as co-firing, additive manufacturing, and laser patterning are analyzed concerning the core requirements of processing glass-ceramics and the Performance of the final products. In this communication, we propose a revised, updated definition of glass-ceramics, which reads “Glass-ceramics are inorganic, non-metallic materials prepared by controlled crystallization of glasses via different processing methods. They contain at least one type of functional crystalline phase and a residual glass. The volume fraction crystallized may vary from ppm to almost 100%”.
KW - Glass-ceramics definition
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-464711
DO - https://doi.org/10.1016/j.jnoncrysol.2018.01.033
SN - 0022-3093
SN - 1873-4812
VL - 501
SP - 3
EP - 10
PB - Elsevier B.V.
AN - OPUS4-46471
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Holzer, Marco
A1 - Johansen, Sidsel M.
A1 - Christensen, Johan F.S.
A1 - Smedskjaer, Morten M.
A1 - Cicconi, Maria Rita
A1 - de Ligny, Dominique
A1 - Müller, Ralf
A1 - de Camargo, Andrea S.S.
A1 - Maaß, Robert
T1 - Direct connection between secondary relaxation mode and fracture toughness in alkali-aluminosilicate glasses
N2 - Oxide glasses are intrinsically brittle, lacking sufficient atomic-scale mechanisms that can relax mechanical stresses in the vicinity of a propagating crack. As a result, fracture is typically well-captured by considering local bond rupture at the crack tip. Here we demonstrate that barrier energies related to the low-temperature 𝛾-relaxation mode in alkali-aluminosilicate glasses are inversely related to the fracture toughness measured via standardized three-point bending fracture experiments. This holds true for both a series with varying cations (Li, Na, K) and one with varying Li concentration. The structural rationale for this finding is gained via Raman spectroscopy. The findings suggest that a fundamental structural relaxation mode measured on bulk specimens can serve as an effective guideline for fracture toughness of oxide glasses. Data for additional silicate glasses support this conclusion.
KW - Fracture toughness
KW - Oxide glass
KW - Mechanical properties
KW - Alkali-aluminosilicate glasses
KW - Internal friction
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-651540
DO - https://doi.org/10.1016/j.mtadv.2025.100669
SN - 2590-0498
VL - 29
SP - 1
EP - 10
PB - Elsevier Ltd.
CY - Amsterdam, Niederlande
AN - OPUS4-65154
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Göbel, M.
A1 - Kirsch, S.
A1 - Schwarze, L:
A1 - Schmidt, L.
A1 - Scholz, H.
A1 - Haußmann, J.
A1 - Klages, M.
A1 - Scholta, J.
A1 - Markötter, Henning
A1 - Alrwashdeh, S.
A1 - Manke, I.
A1 - Müller, Bernd R.
T1 - Transient limiting current measurements for characterization of gas diffusion layers
N2 - The water management in proton exchange membrane fuel cells (PEMFC) is strongly influenced by the design of the gas diffusion layers (GDL). Limiting current measurements in small-scale cells operating at high stoichiometries are useful to determine the oxygen transport resistance. The oxygen transport resistance increases, once water condenses inside the GDL. In this study a new electrochemical method for voltage loss estimation of GDL induced oxygen transport losses are presented. This new method, referred to as “transient limiting current” (TLC), is compared with the literature method. TLC allows a direct estimation of oxygen transport resistance at an arbitrarily conditioned state. This study also presents a case study of liquid water visualization of a PEM fuel cell with varying GDLs types.
With the help of quasi in-situ synchrotron X-ray computed tomography and time resolved radiography measurements we investigate appearance and distribution of liquid water inside the GDLs under limiting current conditions.
KW - In-situ characterization of GDLs
KW - In-situ synchrotron X-ray computed tomography
KW - In-situ synchrotron X-ray radiography
KW - BAMline
PY - 2018
DO - https://doi.org/10.1016/j.jpowsour.2018.09.003
SN - 0378-7753
SN - 1873-2755
VL - 402
SP - 237
EP - 245
PB - Elsevier B.V.
AN - OPUS4-46552
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cant, D. J. H.
A1 - Minelli, C.
A1 - Sparnacci, K.
A1 - Müller, Anja
A1 - Kalbe, H.
A1 - Stoger-Pollach, M.
A1 - Unger, Wolfgang
A1 - Werner, W. S. M.
A1 - Shard, A. G.
T1 - Surface-Energy Control and Characterization of Nanoparticle Coatings
N2 - Accurate and reproducible measurement of the structure and properties of high-value nanoparticles is extremely important for their commercialization. A significant proportion of engineered nanoparticle systems consist of some form of nominally core-shell structure, whether by design or unintentionally. Often, these do not form an ideal core-shell structure, with typical deviations including polydispersity of the core or shell, uneven or incomplete shells, noncentral cores, and others. Such systems may be created with or without intent, and in either case an understanding of the conditions for formation of such particles is desirable. Precise determination of the structure, composition, size, and shell thickness of such particles can prove challenging without the use of a suitable range of characterization techniques. Here, the authors present two such polymer core-shell nanoparticle systems, consisting of polytetrafluoroethylene cores coated with a range of thicknesses of either polymethylmethacrylate or polystyrene. By consideration of surface energy, it is shown that these particles are expected to possess distinctly differing coating structures, with the polystyrene coating being incomplete. A comprehensive characterization of these systems is demonstrated, using a selection of complementary techniques including scanning electron microscopy, scanning transmission electron microscopy, thermogravimetric analysis, dynamic light scattering, differential centrifugal sedimentation, and X-ray photoelectron spectroscopy. By combining the results provided by these techniques, it is possible to achieve superior characterization and understanding of the particle structure than could be obtained by considering results separately.
KW - Nanoparticles
KW - Core-shell
KW - XPS
KW - Size
KW - Thickness
KW - Damage
PY - 2020
DO - https://doi.org/10.1021/acs.jpcc.0c02161
VL - 124
IS - 20
SP - 11200
EP - 11211
PB - ACS
CY - Washington DC
AN - OPUS4-50899
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Henning, L. M.
A1 - Müller, J. T.
A1 - Smales, Glen Jacob
A1 - Pauw, Brian Richard
A1 - Schmidt, J.
A1 - Bekheet, M. F.
A1 - Gurlo, A.
A1 - Simon, U.
T1 - Hierarchically porous and mechanically stable monoliths from ordered mesoporous silica and their water filtration potential
N2 - Mechanically stable structures with interconnected hierarchical porosity combine the benefits of both small
and large pores, such as high surface area, pore volume, and good mass transport capabilities. Hence, lightweight micro-/meso-/macroporous monoliths are prepared from ordered mesoporous silica COK-12 by means of spark plasma sintering (SPS, S-sintering) and compared to conventionally (C-) sintered monoliths. A multi-scale model is developed to fit the small angle X-ray scattering data and obtain information on the hexagonal lattice parameters, pore sizes from the macro to the micro range, as well as the dimensions of the silica population. For both sintering techniques, the overall mesoporosity, hexagonal pore ordering, and amorphous character are preserved. The monoliths' porosity (77–49%), mesopore size (6.2–5.2 nm), pore volume (0.50–0.22 g cm-3
), and specific surface area (451–180 m2 g-1) decrease with increasing processing temperature and pressure. While the difference in porosity is enhanced, the
structural parameters between the C-and S-sintered monoliths are largely converging at 900 C, except for the mesopore size and lattice parameter, whose dimensions are more extensively preserved in the
S-sintered monoliths, however, coming along with larger deviations from the theoretical lattice. Their higher mechanical properties (biaxial strength up to 49 MPa, 724 MPa HV 9.807 N) at comparable porosities and ability to withstand ultrasonic treatment and dead-end filtration up to 7 bar allow S-sintered monoliths to reach a high permeance (2634 L m-2 h-1 bar-1), permeability (1.25 x 10^-14 m2), and ability to reduce the chemical oxygen demand by 90% during filtration of a surfactant-stabilized oil in water emulsion, while indicating reasonable resistance towards fouling.
KW - SAXS
KW - Hierarchically porous
KW - Silica
KW - Water filtration
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555928
DO - https://doi.org/10.1039/D2NA00368F
SN - 2516-0230
SP - 1
EP - 17
PB - Royal Society of Chemistry
CY - Cambridge
AN - OPUS4-55592
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wiedensohler, A.
A1 - Wiesner, A.
A1 - Weinhold, K.
A1 - Birmili, W.
A1 - Herrmann, M.
A1 - Merkel, M.
A1 - Müller, T.
A1 - Pfeifer, S.
A1 - Schmidt, A.
A1 - Tuch, T.
A1 - Velarde, F.
A1 - Quincey, P.
A1 - Seeger, Stefan
A1 - Nowak, A.
T1 - Mobility particle size spectrometers: Calibration procedures and measurement uncertainties
N2 - Mobility particle size spectrometers (MPSS) belong to the essential instruments in aerosol science that determine the particle number size distribution (PNSD)in the submicrometer size range. Following calibration procedures and target uncertainties against standards and reference instruments are suggested for a complete MPSS quality assurance program: a) calibration of the CPC counting efficiency curve (within 5% for the plateau counting efficiency; within 1 nm for the 50% detection efficiency diameter), b) sizing calibration of the MPSS, using a certified polystyrene latex (PSL) particle size standard at 203 nm (within 3%), c) intercomparison of the PNSD of the MPSS (within 10% and 20% of the dN/dlogDP concentration for the particle size range 20 – 200 nm and 200 to 800 nm, respectively), and d) intercomparison of the integral PNC of the MPSS (within 10%). Furthermore, following measurement uncertainties have been investigated: a) PSL particle size standards in the range from 100-500nm match within 1% after sizing calibration at 203 nm. b) Bipolar diffusion chargers based on the radioactive nuclides Kr85, Am241 and Ni63 and a new ionizer based on corona discharge follow the recommended bipolar charge distribution, while soft X-ray-based charges may alter faster than expected. c) The use of a positive high voltage supply show a 10% better performance than a negative one. d) The intercomparison of the integral PNC of an MPSS against the total number concentration is still within the target uncertainty at an ambient pressure of approximately 500 hPa.
KW - Measurement uncertainties
KW - Mobility particle size spectrometer (MPPS)
KW - Condensation particle counter (CPC)
KW - Calibration
PY - 2017
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-425060
DO - https://doi.org/10.1080/02786826.2017.1387229
SN - 1521-7388
VL - 52
IS - 2
SP - 146
EP - 164
PB - Tailor & Francis
CY - USA
AN - OPUS4-42506
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Heyn, A.
A1 - Müller, Thoralf
A1 - Balzer, M.
A1 - Fenker, M.
A1 - Kappl, H.
T1 - Corrosion protection mechanisms of TiMgN hard coatings on steel
N2 - Hard coated steel components are used in a wide application range, mostly for protective, wear resistant and decorative purposes. Despite of these coatings being regarded as relatively dense, there is always a high risk of localized corrosion when a coated low alloyed steel component encounters a surrounding high humidity atmosphere or even an aqueous medium. An approach to enhance the corrosion properties is the addition of magnesium to physical vapor deposited hard coatings, like TiN. It has been found that there is a remarkable increase in corrosion resistance in dependence of magnesium content of the TiMgN coating and its surface properties. In this work the authors will explain the underlying corrosion protection mechanisms by means of electrochemical and analytical studies. The positive impact of magnesium in the coating relates on its preferred dissolution vs. steel. This causes the potential to shift to more negative direction with respect to the steel substrate and additionally leads to a temporarily passivation of the steel due to alkalization of the surrounding electrolyte by formation of magnesium hydroxide.
T2 - 20. Werkstofftechnisches Kolloquium
CY - Chemnitz, Germany
DA - 14.03.2018
KW - Corrosion
KW - Titanium nitride
KW - PVD hard coating
KW - magnesium
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-457117
DO - https://doi.org/10.1088/1757-899X/373/1/012009
SN - 1757-8981
VL - 373
IS - 1
SP - 012009, 1
EP - 10
PB - IOP Publishing Ltd
AN - OPUS4-45711
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Prewitz, M.
A1 - Gaber, M.
A1 - Müller, Ralf
A1 - Marotzke, C.
A1 - Holtappels, Kai
T1 - Polymer coated glass capillaries and structures for high-pressure hydrogen storage: Permeability and hydrogen tightness
N2 - The hydrogen tightness of high-pressure hydrogen storage is a Basic criterion for long-term storage. The H2 permeation coefficients of epoxy resin and a glass lacquer were determined to enable the geometric optimization of a glass capillary storage. It was found that the curing conditions have no significant influence on the H2 permeation coefficient of resin.
The H2 permeation coefficient of epoxy resin is only about three orders of Magnitude greater than that of borosilicate glass. This suggests that the initial pressure of 700 bar takes about 2.5 years to be halved in capillary array storage. Therefore, a high-pressure hydrogen storage tank based on glass capillaries is ideally suited for long-term storage in mobile applications.
KW - Permeability
KW - Glass capillaries
KW - Coating
KW - Hydrogen storage
KW - Long-term calculation
KW - Epoxy resin
PY - 2018
DO - https://doi.org/10.1016/j.ijhydene.2017.12.092
SN - 0360-3199
VL - 43
IS - 11
SP - 5637
EP - 5644
PB - Elsevier
AN - OPUS4-44327
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller-Mai, C.M.
A1 - Berger, Georg
A1 - Stiller, M.
A1 - Gildenhaar, Renate
A1 - Jörn, Daniela
A1 - Ploska, Ute
A1 - Houshmand, A.
A1 - Bednarek, A.
A1 - Koch, C.
A1 - Knabe, C.
T1 - Evaluation of degradable bone cements for percutaneous augmentation of bone defects
KW - Bone defect
KW - Bioactive bone cement
KW - Calcium alkali orthophosphates
KW - Histology
KW - Histomorphometry
KW - Knochendefekt
KW - Bioaktiver Knochenzement
KW - Calciumalkaliorthophosphat
KW - Histologie
KW - Histomorphometrie
PY - 2010
DO - https://doi.org/10.1002/mawe.201000706
SN - 0933-5137
SN - 1521-4052
VL - 41
IS - 12
SP - 1040
EP - 1047
PB - Wiley-VCH Verl.
CY - Weinheim
AN - OPUS4-22891
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, M.
A1 - Kaiser, Martin
A1 - Stachowski, G.M.
A1 - Resch-Genger, Ute
A1 - Gaponik, N.
A1 - Eychmüller, A.
T1 - Photoluminescence quantum yield and matrix-induced luminescence enhancement of colloidal quantum dots embedded in ionic crystals
N2 - The incorporation of colloidal quantum dots (QDs) into solid matrices, especially ionic salts, holds several advantages for industrial applications. Here, we demonstrated via absolute measurements of photoluminescence quantum yields (PL-QY) that the photoluminescence of aqueous CdTe QDs can be considerably increased upon incorporation into a salt matrix with a simple crystallization procedure. Enhancement factors of up to 2.8 and a PL-QY of 50 to 80%, both in NaCl crystals and incorporated in silicone matrices, were reached. The fact that the achievable PL enhancement factors depend strongly on PL-QY of the parent QDs can be described by the change of the dielectric surrounding and the passivation of the QD surface, modifying radiative and nonradiative rate constants. Time-resolved PL measurements revealed noncorrelating PL lifetimes and PL-QY, suggesting that weakly emissive QDs of the ensemble are more affected by the enhancement mechanism, thereby influencing PL-QY and PL lifetime in a different manner.
PY - 2014
DO - https://doi.org/10.1021/cm5009043
SN - 0897-4756
SN - 1520-5002
VL - 26
IS - 10
SP - 3231
EP - 3237
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-31074
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schiro, G.
A1 - Müller, T.
A1 - Verch, G.
A1 - Sommerfeld, Thomas
A1 - Mauch, Tatjana
A1 - Koch, Matthias
A1 - Grimm, V.
A1 - Müller, M.E.H.
T1 - The distribution of mycotoxins in a heterogeneous wheat field in relation to microclimate, fungal and bacterial abundance
N2 - Aim: To observe the variation in accumulation of Fusarium and Alternaria mycotoxins across a topographically heterogeneous field and tested biotic (fungal and bacterial abundance) and abiotic (microclimate) parameters as explanatory variables.
Methods and Results: We selected a wheat field characterized by a diversified topography, to be responsible for variations in productivity and in canopy-driven microclimate. Fusarium and Alternaria mycotoxins where quantified in wheat ears at three sampling dates between flowering and harvest at 40 points.
Tenuazonic acid (TeA), alternariol (AOH), alternariol monomethyl ether (AME), tentoxin (TEN), deoxynivalenol (DON), zearalenone (ZEN) and deoxynivalenol-3-Glucoside (DON.3G) were quantified. In canopy temperature, air and soil humidity were recorded for each point with data-loggers. Fusarium spp. as trichothecene producers, Alternaria spp. and fungal abundances were assessed using qPCR. Pseudomonas fluorescens bacteria were quantified with a culture based method. We only found DON, DON.3G, TeA and TEN to be ubiquitous across the whole field, while AME, AOH and ZEN were only occasionally detected. Fusarium was more abundant in spots with high soil humidity, while Alternaria in warmer and drier spots. Mycotoxins correlated differently to the observed explanatory variables: positive correlations between DON accumulation, tri 5 gene and Fusarium abundance were clearly detected.
The correlations among the others observed variables, such as microclimatic conditions, varied among the sampling dates. The results of statistical model identification do not exclude that species coexistence could influence mycotoxin production.
Conclusions: Fusarium and Alternaria mycotoxins accumulation varies heavily across the field and the sampling dates, providing the realism of landscapescale studies. Mycotoxin concentrations appear to be partially explained by biotic and abiotic variables.
Significance and Impact of the Study: We provide a useful experimental design and useful data for understanding the dynamics of mycotoxin biosynthesis in wheat.
KW - Alternaria
KW - Deoxynivalenol
KW - Food Safety
KW - Fusarium
KW - Pseudomonas fluorescens
KW - Tenuazonic acid
PY - 2019
DO - https://doi.org/10.1111/jam.14104
SN - 1365-2672
SN - 1364-5072
VL - 126
IS - 1
SP - 177
EP - 190
PB - Wiley
AN - OPUS4-47161
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hoesl, Simone
A1 - Neumann, B.
A1 - Techritz, Sandra
A1 - Sauter, G.
A1 - Simon, R.
A1 - Schlüter, H.
A1 - Linscheid, M. W.
A1 - Theruing, F.
A1 - Müller, Larissa
A1 - Jakubowski, Norbert
T1 - Internal standardization of LA-ICP-MS immunoimaging via printing of universal metal spiked inks onto tissue sections
N2 - Formalin-fixed paraffin-embedded (FFPE) specimen from biopsy materials are a widespread sample format for pathologists and medical researchers. Pathologists are archiving vast numbers of FFPE samples which can be stored for decades. Conventional immunohistochemical staining (IHC) of biomarkers on FFPE tissue sections is one of the most important analytical techniques for cancer diagnosis and pathology in general. However standardization for IHC samples and quality management is tedious and differs significantly from clinic to clinic. Combining established IHC staining strategies with modern mass spectrometry mediated methods would increase it`s potential and enable access of large FFPE archives for multiplexed quantitation purposes. In this work element mass spectrometry and a new ink-jet printed internal standardization approach was successfully combined with IHC staining to facilitate quantitative multiplex assays for archived FFPE samples. The printing strategy improves elemental image resolution and reproducibility of paraffin embedded breast cancer tissue sections in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) using conventional IHC staining as a model system to investigate the new capabilities of this technique. For the internal standardization we applied a conventional CD-ink-jet printer to print a metal spiked ink onto the top of thin layer tissue sections with constant density. Printing was carried out in a direct comparison to an iodination of the tissue section as previously described as an alternative standardization method. The use of the printed internal standard allowed correction of the fluctuation during the laser ablation process and compensated instrumental drift effects. Mediated by the ink correction approach we achieved better signal-to-background-ratios (SBR) of 74 and better spatial resolution of 30 µm compared to iodination (SBR=23). This improved performance was demonstrated on tumorous areas in FFPE breast cancer tissue sections and allowing detection of Her-2 in tumorous areas of this tissue with significantly improved contrast.
KW - Internal standardization
KW - LA-ICP-MS
KW - Immuno imaging
PY - 2016
DO - https://doi.org/10.1039/c5ja00409h
SN - 0267-9477
SN - 1364-5544
VL - 31
IS - 3
SP - 801
EP - 808
AN - OPUS4-35711
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scharlach, C.
A1 - Müller, Larissa
A1 - Wagner, S.
A1 - Kobayashi, Y.
A1 - Kratz, H.
A1 - Ebert, M.
A1 - Jakubowski, Norbert
A1 - Schellenberger, E.
T1 - LA-ICP-MS allows quantitative microscopy of europium-doped iron oxide nanoparticles and is a possible alternative to ambiguous Prussian blue iron staining
N2 - The development of iron oxide nanoparticles for biomedical applications requires accurate histological evaluation. Prussian blue iron staining is widely used but may be unspecific when tissues contain substantial endogenous iron. Here we tested whether microscopy by laser ablation coupled to inductively coupled plasma mass spectrometry (LA-ICP-MS) is sensitive enough to analyze accumulation of very small iron oxide particles (VSOP) doped with europium in tissue sections.
KW - Atherosclerotic plaques
KW - LA-ICP-MS microscopy
KW - Quantification
KW - Element microscopy
KW - Histology
PY - 2016
DO - https://doi.org/10.1166/jbn.2016.2230
SN - 1550-7033
SN - 1550-7041
VL - 12
IS - 5
SP - 1001
EP - 1010
AN - OPUS4-36189
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lengas, Nikolaos
A1 - Schlick-Hasper, Eva
A1 - Müller, Karsten
A1 - Neitsch, Marcel
A1 - Johann, Sergej
A1 - Zehn, M.
T1 - Development of an analysis and testing concept for the evaluation of impact targets in the mechanical safety testing of dangerous goods packagings
N2 - The mechanical and geometrical properties of impact targets greatly influence the outcome of a drop test. The International Agreement concerning the International Carriage of Dangerous Goods by Road (ADR) as well as ISO 2248 describe the characteristics of impact targets for drop tests of dangerous goods packagings.
According to these regulations, the impact target’s surface needs to be unyielding, under testing conditions non-deformable, flat, and integral with a mass at least 50 times that of the heaviest packaging to be tested. The problem is that many production facilities, especially manufacturers of corrugated fibreboard boxes, do not have their own testing device with the required 50 times mass ratio of the impact target for a regulation compliant drop test during series production. Furthermore, at UN level it is considered necessary to revise these requirements.
In the present paper, the impact target requirements are examined in detail and compared with those in other technical areas (e.g., impact target for container for the transport of radioactive materials). A research method is being developed to investigate the dependency between the mass ratio of the packaging and the target as well as the damage resistance of a drop tested package in relation to specific design characteristics. The results are of high relevance for industry purposes and intended to ensure a uniform level of safety assessment for the mechanical testing of dangerous goods packagings.
KW - Corrugated fibreboard boxes
KW - Dangerous goods packagings
KW - Drop test
KW - Impact target
KW - Structural dynamics
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-549660
DO - https://doi.org/10.1002/pts.2656
SN - 0894-3214
SN - 1099-1522
VL - 35
IS - 9
SP - 689
EP - 700
PB - Wiley
CY - New York, NY
AN - OPUS4-54966
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lengas, Nikolaos
A1 - Müller, Karsten
A1 - Schlick-Hasper, Eva
A1 - Neitsch, Marcel
A1 - Johann, Sergej
A1 - Zehn, M. W.
T1 - Improved criteria for evaluating impact targets in regulative drop tests of dangerous goods packagings
N2 - For dangerous goods packagings, drop testing onto an essential unyielding target can be used to assess the mechanical resistance to impact loads. Adopted regulations like ADR/RID require that the impact surface provided shall be integral with a mass at least 50 times than that of the heaviest package to be tested. The problem is that many manufacturers do not possess impact targets that satisfy the required 50 times mass ratio for regulative drop tests during series production. The objective of this work is to verify existing and define improved criteria for impact target structures based on systematic investigations. Previous evidence highlights the relevance of other parameters in addition to the mass ratio. Therefore, in this research, a variation of drop test parameters was carried out experimentally. Furthermore, numerical vibration analysis was applied to investigate the deformability of the impact surface. The results conclude that the mass ratio of 1:50 cannot be defined as a decisive criterion. In order to determine the influence of further drop test parameters, the research findings were used to validate a parametric model which assesses impact target deflection. An approximation quality of over 90 % was achieved. As a result, new evaluation criteria are proposed. Firstly, a method for identifying critical impact target designs is provided. Secondly, a new comprehensive formula compares the approximated maximum deflection of a real impact target to the respective theoretical threshold derived from a worst-case assumption. In practice, this leads to great advantages in the evaluation of already installed impact targets for dangerous goods packagings.
KW - Corrugated fibreboard box
KW - Dangerous goods packagings
KW - Drop test
KW - Impact target
KW - Mechanical response
KW - Steel drum
KW - Structural dynamics
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576985
DO - https://doi.org/10.1002/pts.2759
SN - 0894-3214
SP - 1
EP - 14
PB - John Wiley & Sons Ltd
AN - OPUS4-57698
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Costabel, S.
A1 - Hiller, Thomas
A1 - Dlugosch, R.
A1 - Kruschwitz, Sabine
A1 - Müller Petke, M.
T1 - Evaluation of single-sided nuclear magnetic resonance technology for usage in geosciences
N2 - Because of its mobility and ability to investigate exposed surfaces, single-sided (SiS) nuclear magnetic resonance (NMR) technology enables new application fields in geosciences. To test and assess its corresponding potential, we compare longitudinal (T1) and transverse (T2) data measured by SiS NMR with those of conventional geoscientific laboratory NMR. We use reference sandstone samples covering a broad range of pore sizes. Our study demonstrates that the lower signal-to-noise ratio of SiS NMR data generally tends to slightly overestimated widths of relaxation time distributions and consequently pore size distributions. While SiS and conventional NMR produce very similar T1 relaxation data, unbiased SiS NMR results for T2 measurements can only be expected for fine material, i.e. clayey or silty sediments and soils with main relaxation times below 0.05s. This limit is given by the diffusion relaxation rate due to the gradient in the primary magnetic field associated with the SiS NMR. Above that limit, i.e. for coarse material, the relaxation data is strongly attenuated. If considering the diffusion relaxation time of 0.2 s in the numerical data inversion process, the information content >0.2s is blurred over a range larger than that of conventional NMR. However, our results show that principle range and magnitudes of the relaxation time distributions are reconstructed to some extent. Regarding these findings, SiS NMR can be helpful to solve geoscientific issues, e.g. to assess the hydro-mechanical properties of the walls of underground facilities or to provide local soil moisture data sets for calibrating indirect remote techniques on the regional scale. The greatest opportunity provided by the SiS NMR technology is the acquisition of profile relaxation data for rocks with significant bedding structures at the µm scale. With this unique feature, SiS NMR can support the understanding and modeling of hydraulic and diffusional anisotropy behavior of sedimentary rocks.
KW - Single-sided NMR
KW - Geosciences
KW - Nuclear magnetic resonance
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561676
DO - https://doi.org/10.1088/1361-6501/ac9800
SN - 0957-0233
VL - 34
IS - 1
SP - 1
EP - 13
PB - IOP Publishing
AN - OPUS4-56167
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Medina, A.
A1 - Ol, M. V.
A1 - Greenblatt, D.
A1 - Müller-Vahl, H.
A1 - Strangfeld, Christoph
T1 - High-Amplitude Surge of a Pitching Airfoil: Complementary Wind- and Water-Tunnel Measurements
N2 - RECENT interest in gust response, rotorcraft forward flight and wind energy, among other applications, has focused on streamwise oscillations of nominally two-dimensional airfoils in attached and separated flows. The airfoil may be simultaneously held at constant incidence or execute some maneuver, such as pitch.
The relative freestream is spatially uniform but temporally unsteady, and this can be accomplished in a ground-test facility in two ways. The first method is to vary the output of the prime mover, such as the rotational speed of the impeller or the blower driving a wind tunnel, or (alternatively) to vary the pressure drop in the tunnel, thereby varying the flow speed in the test section, despite nominally constant primemover revolutions per minute. The second method is used to keep the tunnel’s operating speed constant, as well as to move the test article in the streamwise direction, fore and aft (for example, via an electric linear motor), such that the relative freestream speed felt by the test article varies according to some waveform. Typically, the latter approach is chosen in water tunnels, where there is too much tunnel-circuit inertia to vary the flow speed directly but where the usually low tunnel test section flow speeds enable large excursions in the relative freestream by oscillation of the test article. In fact, outright reverse flow is possible by moving the test article in the laboratory frame at a higher speed than the water-tunnel flow speed. In either case, a sinusoidal relative-speed waveform is the most intuitively realizable, and this can be combined with similar oscillations in the airfoil incidence angle or other kinematics. Although the two methods of realizing streamwise oscillations are mechanically distinct, experimental comparisons between an oscillating test article in a water tunnel and a stationary test article in a wind tunnel with a louvermechanismhave demonstrated agreement in themeasured lift and drag histories. Such experimentswere performed by Granlund et al. for a 10% freestream amplitude oscillation and fixed airfoil incidence, comparing a free-surface water tunnel and a closed-circuit wind tunnel. After buoyancy was subtracted from the wind-tunnel data (resulting from the louver pressure drop) and the model inertia subtracted from the water-tunnel data (resulting from acceleration of the test article), the remaining lift and drag histories matched well at the low freestream oscillation amplitude regime. The work of Granlund et al. was later extended to high-advance-ratio streamwise oscillations of 50% amplitude by Greenblatt et al., where the aerodynamic histories of the water-tunnel and wind-tunnel facilities were compared in combined pitch and freestreamoscillations (governed by relative pitch phase), pure pitch oscillations, and purely freestream oscillations. Agreement between the two facilities’ data for fixed-incidence streamwise oscillations was reasonably good, and in fact, better than agreement in just the static lift and drag, evidently owing to differences in blockage and model-support systems. Additionally, Greenblatt et al. determined there was no strong coupling between simultaneous freestream oscillations and pitch oscillations on resultant lift and moment coefficients.
KW - Wind energy
KW - Dynamic stall
KW - Deep stall
KW - Airfoil surging
KW - Airfoil pitching
PY - 2018
DO - https://doi.org/10.2514/1.J056408
SN - 0001-1452
SN - 1533-385X
VL - 56
IS - 4
SP - 1703
EP - 1709
PB - American Institute of Aeronautics and Astronautics
AN - OPUS4-43994
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wolff, M.
A1 - Wonneberger, R.
A1 - Freiberg, K.E.
A1 - Hertwig, Andreas
A1 - Bonse, Jörn
A1 - Giebeler, L.
A1 - Koitzsch, A.
A1 - Kunz, C.
A1 - Weber, H.
A1 - Hufenbach, J.K.
A1 - Müller, F.A.
A1 - Gräf, S.
T1 - Formation of laser-induced periodic surface structures on Zr-based bulk metallic glasses with different chemical composition
N2 - Bulk metallic glasses (BMG) are amorphous metal alloys known for their unique physical and mechanical properties. In the present study, the formation of femtosecond (fs) laser-induced periodic surface structures (LIPSS) on the Zr-based BMGs Zr46Cu46Al8, Zr61Cu25Al12Ti2, Zr52.5Cu17.9Al10Ni14.6Ti5 (Vit105) and Zr57Cu15.4Al10Ni12.6Nb5 (Vit106) was investigated as a function of their different chemical composition. For this purpose, LIPSS were generated on the sample surfaces in an air environment by fs-laser irradiation (λ = 1025 nm, τ = 300 fs, frep = 100 kHz). The surface topography was characterized by scanning electron microscopy and atomic force microscopy. Moreover, the impact of LIPSS formation on the structure and chemical surface composition was analyzed before and after fs-laser irradiation by X-ray diffraction and X-ray photoelectron spectroscopy as well as by transmission electron microscopy in combination with energy dispersive X-ray spectroscopy. Despite the different chemical composition of the investigated BMGs, the fs-laser irradiation resulted in almost similar properties of the generated LIPSS patterns. In the case of Zr61Cu25Al12Ti2, Vit105 and Vit106, the surface analysis revealed the preservation of the amorphous state of the materials during fs-laser irradiation. The study demonstrated the presence of a native oxide layer on all pristine BMGs. In addition, fs-laser irradiation results in the formation of laser-induced oxide layers of larger thickness consisting of an amorphous ZrAlCu-oxide. The precise laser-structuring of BMG surfaces on the nanoscale provides a versatile alternative to thermoplastic forming of BMG surfaces and is of particular interest for the engineering of functional material surfaces.
KW - Bulk metallic glasses
KW - Femtosecond laser
KW - Laser-induced periodic surface structures (LIPSS)
KW - Chemical analysis
KW - Oxidation
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581799
DO - https://doi.org/10.1016/j.surfin.2023.103305
SN - 2468-0230
VL - 42
SP - 1
EP - 11
PB - Elsevier B.V.
AN - OPUS4-58179
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stephan, H.
A1 - Walther, M.
A1 - Fähnemann, S.
A1 - Ceroni, P.
A1 - Molloy, J.K.
A1 - Bergamini, G.
A1 - Heisig, F.
A1 - Müller, C.E.
A1 - Kraus, Werner
A1 - Comba, P.
T1 - Bispidines for dual imaging
N2 - The efficient transformation of the hexadentate bispidinol 1 into carbamate derivatives yields functional bispidines enabling convenient functionalization for targeted imaging. The BODIPY-substituted bispidine 3 combines a coordination site for metal ions, such as radioactive 64CuII, with a fluorescent unit. Product 3 was thoroughly characterized by standard analytical methods, single crystal X-ray diffraction, radiolabeling, and photophysical analysis. The luminescence of ligand 3 was found to be strongly dependent on metal ion coordination: CuII quenches the BODIPY fluorescence, whereas NiII and ZnII ions do not affect it. It follows that, in imaging applications with the positron emitter 64CuII, residues of its origin from enriched 64Ni and the decay products 64NiII and 64ZnII, efficiently restore the fluorescence of the ligand. This allows for monitoring of the emitted radiation as well as the fluorescence signal. The stability of the 64CuII–3 complex is investigated by transmetalation experiments with ZnII and NiII, using fluorescence and radioactivity detection, and the results confirm the high stability of 64CuII–3. In addition, metal complexes of ligand 3 with the lanthanide ions TbIII, EuIII, and NdIII are shown to exhibit emission of the BODIPY ligand and the lanthanide ion, thus enabling dual emission detection.
KW - Bispidines
KW - Chelates
KW - Imaging agents
KW - Lanthanides
KW - Radiolabeling
KW - Nuclear medical application
KW - Radioactive labelling
KW - SPECT
PY - 2014
DO - https://doi.org/10.1002/chem.201404086
SN - 0947-6539
SN - 1521-3765
VL - 20
IS - 51
SP - 17011
EP - 17018
PB - Wiley-VCH Verl.
CY - Weinheim
AN - OPUS4-32320
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hösl, Simone
A1 - Neumann, B.
A1 - Techritz, Sandra
A1 - Linscheid, M.
A1 - Theuring, F.
A1 - Scheler, C.
A1 - Jakubowski, Norbert
A1 - Müller, Larissa
T1 - Development of a calibration and standardization procedure for LA-ICP-MS using a conventional ink-jet printer for quantification of proteins in electro- and western-blot assays
N2 - We developed new procedures for internal standardization and calibration to be used for laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for elemental micro mapping imaging of biological samples like Western blot membranes and tissue sections. These procedures are based on printing of metal spiked inks onto the top of thin layer samples for simultaneous internal standardization and calibration of LA-ICP-MS. In the case of internal standardization the ink is spiked with indium as an internal standard and homogenously printed over the entire membrane (size 56 cm2) prior to LA-ICP-MS detection, a standard deviation (RSD) value of 2% was achieved. In the second approach the metal content of lanthanide tagged proteins and antibodies after biological work flows was quantified by LA-ICP-MS on nitro-cellulose membranes. In this case the inks spiked with varying metals were printed with different densities on the same nitrocellulose membranes in well-defined squares to produce matrix-matched calibration standards. For validation and calibration the ink squares were excised and the specific metal content was measured by liquid ICP-MS after solubilization of the membrane slice. For the printed calibration standard limits of detection (LOD) of <4 fmol for different metals and relative process standard deviations of 12% only were determined via LA-ICP-MS.
PY - 2014
DO - https://doi.org/10.1039/c4ja00060a
SN - 0267-9477
SN - 1364-5544
VL - 29
IS - 7
SP - 1282
EP - 1291
PB - Royal Society of Chemistry
CY - London
AN - OPUS4-31171
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Paul, Andrea
A1 - Meyer, Klas
A1 - Ruiken, Jan-Paul
A1 - Illner, M.
A1 - Müller, D.-N.
A1 - Esche, E.
A1 - Wozny, G.
A1 - Westad, Frank
A1 - Maiwald, Michael
T1 - Process spectroscopy in microemulsions — Raman spectroscopy for online monitoring of a homogeneous hydroformylation process
N2 - A major industrial reaction based on homogeneous catalysis is hydroformylation for the production of aldehydes from alkenes and syngas. Hydroformylation in microemulsions, which is currently under investigation at Technische Universität Berlin on a mini-plant scale, was identified as a cost efficient approach which also enhances product selectivity. Herein, we present the application of online Raman spectroscopy on the reaction of 1-dodecene to 1-tridecanal within a microemulsion. To achieve a good representation of the operation range in the mini-plant with regard to concentrations of the reactants a design of experiments was used. Based on initial Raman spectra partial least squares regression (PLSR) models were calibrated for the prediction of 1-dodecene and 1-tridecanal. Limits of predictions arise from nonlinear correlations between Raman intensity and mass fractions of compounds in the microemulsion system. Furthermore, the prediction power of PLSR models becomes limited due to unexpected by-product formation. Application of the lab-scale derived calibration spectra and PLSR models on online spectra from a mini-plant operation yielded promising estimations of 1-tridecanal and acceptable predictions of 1-dodecene mass fractions suggesting Raman spectroscopy as a suitable technique for process analytics in microemulsions.
KW - Raman
KW - Online
KW - Chemometrics
KW - Hydroformylation
KW - Mini-plant
KW - Microemulsion
PY - 2017
DO - https://doi.org/10.1088/1361-6501/aa54f0
SN - 1361-6501
SN - 0957-0233
VL - 28
IS - 3
SP - 035502-1
EP - 035502-11
PB - IOP Publishing Ltd
CY - UK
AN - OPUS4-39032
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, Jan P.
A1 - Götschel, S.
A1 - Maierhofer, Christiane
A1 - Weiser, M.
T1 - Determining the Material Parameters for the Reconstruction of Defects in Carbon Fiber Reinforced Polymers from Data Measured by Flash Thermography
N2 - Flash thermography is a fast and reliable non-destructive testing method for the investigation of defects in carbon fiber reinforced polymer (CFRP) materials. In this paper numerical simulations of transient thermography data are presented, calculated for a quasi-isotropic flat bottom hole sample. They are compared to experimental data. These simulations are one important step towards the quantitative reconstruction of a flaw by assessing thermographic data. The applied numerical model is based on the finite-element method, extended by a semi-analytical treatment of the boundary of the sample, which is heated by the flash light. A crucial part for a reliable numerical model is the prior determination of the material parameters of the specimen as well as of the experimental parameters of the set-up. The material parameters in plane and in depth diffusivity are measured using laser line excitation. In addition, the absorption and heat transfer process of the first layers is investigated using an IR microscopic lens. The performance of the two distinct components of CFRP during heating – epoxy resin and carbon fibers – is examined. Finally, the material parameters are optimized by variation and comparison of the simulation results to the experimental data. The optimized parameters are compared to the measured ones and further methods to ensure precise material parameter measurements are discussed.
T2 - 43rd Review of Progress in Quantitative Nondestructive Evaluation
CY - Atlanta, GA, USA
DA - 17.07.2016
KW - Aktive Thermografie
KW - Thermische Diffusivität
KW - Zerstörungsfreie Prüfung
KW - Kohlenstofffaserverstärkter Kunststoff
KW - CFK
KW - Active thermography
KW - Thermal diffusivity
KW - Non-Destructive testing
KW - Carbon fiber reinforced polymer
KW - CFRP
PY - 2017
SN - 978-0-7354-1474-7
DO - https://doi.org/10.1063/1.4974671
SN - 0094-243X
VL - 1806
IS - 1
SP - UNSP 100006-1
EP - 11
PB - AIP Publishing
CY - Melville, NY, USA
AN - OPUS4-39332
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Meyer, Klas
A1 - Ruiken, J.-P.
A1 - Illner, M.
A1 - Paul, Andrea
A1 - Müller, D.
A1 - Esche, E.
A1 - Wozny, G.
A1 - Maiwald, Michael
T1 - Process spectroscopy in microemulsions - setup and multi-spectral approach for reaction monitoring of a homogeneous hydroformylation process
N2 - Reaction monitoring in disperse systems, such as emulsions, is of significant technical importance in various disciplines like biotechnological engineering, chemical industry, food science, and a growing number other technical fields. These systems pose several challenges when it comes to process analytics, such as heterogeneity of mixtures, changes in optical behavior, and low optical activity. Concerning this, online nuclear magnetic resonance (NMR) spectroscopy is a powerful technique for process monitoring in complex reaction mixtures due to its unique direct comparison abilities, while at the same time being non-invasive and independent of optical properties of the sample. In this study the applicability of online-spectroscopic methods on the homogeneously catalyzed hydroformylation system of 1-dodecene to tridecanal is investigated, which is operated in a mini-plant scale at Technische Universität Berlin. The design of a laboratory setup for process-like calibration experiments is presented, including a 500 MHz online NMR spectrometer, a benchtop NMR device with 43 MHz proton frequency as well as two Raman probes and a flow cell assembly for an ultraviolet and visible light (UV/VIS) spectrometer. Results of high-resolution online NMR spectroscopy are shown and technical as well as process-specific problems observed during the measurements are discussed.
KW - Online-spectroscopy
KW - Quantitative NMR spectroscopy
KW - Process analytical technology
KW - Microemulsions
PY - 2017
DO - https://doi.org/10.1088/1361-6501/aa54f3
SN - 0957-0233
SN - 1361-6501
VL - 28
IS - 3
SP - 035501-1
EP - 035501-11
PB - IOP Publishing Ltd.
AN - OPUS4-39091
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gianneo, A.
A1 - Carboni, M.
A1 - Müller, Christina
A1 - Ronneteg, U.
T1 - PAUT inspection of copper canister: structural attenuation and POD formulation
N2 - For inspection of thick-walled (50mm) copper canisters for final disposal of spent nuclear fuel in Sweden, ultrasonic inspection using phased array technique (PAUT) is applied. Because thick-walled copper is not commonly used as a structural material, previous experience on Phased Array Ultrasonic Testing for this type of application is limited. The paper presents the progress in understanding the amplitudes and attenuation changes acting on the Phased Array Ultrasonic Testing inspection of copper canisters. Previous studies showed the existence of a low pass filtering effect and a heterogeneous grain size distribution along the depth, thus affecting both the detectability of defects and their "Probability of Detection" determination. Consequently, the difference between the first and second back wall echoes were not sufficient to determine the local attenuation (within the inspection range), which affects the signal response for each individual defect. Experimental evaluation of structural attenuation was carried out onto step-wedge samples cut from full-size, extruded and pierced&drawn, copper canisters. Effective attenuation values has been implemented in numerical simulations to achieve a Multi Parameter Probability of Detection and to formulate a Model Assisted Probability of Detection through a Monte-Carlo extraction model.
T2 - 42nd Annual Review of Progress in Quantitative Nondestructive Evaluation (QNDE)
CY - Minneapolis, MN, USA
DA - 26.07.2015
KW - Phased array ultrasonic testing
KW - POD
KW - Copper
PY - 2016
DO - https://doi.org/10.1063/1.4940649
SN - 0094-243X
VL - 1706
SP - Article: 200005, 1
EP - 13
PB - AIP Publishing
AN - OPUS4-37592
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Debatin, F.
A1 - Thomas, A.
A1 - Kelling, A.
A1 - Hedin, N.
A1 - Bacsik, Z.
A1 - Senkovska, I.
A1 - Kaskel, S.
A1 - Junginger, M.
A1 - Müller, H.
A1 - Schilde, U.
A1 - Jäger, Christian
A1 - Friedrich, A.
A1 - Holdt, H.-J.
T1 - In situ synthesis of an imidazolate-4-amide-5-imidate ligand and formation of a microporous zinc-organic framework with H2-and CO2-storage ability
KW - Metal-organic framework
KW - Synthesis
KW - XRD
KW - FTIR
KW - NMR
KW - Gas sorption
KW - Microporous materials
KW - N,O ligands
KW - Solvothermal synthesis
PY - 2010
DO - https://doi.org/10.1002/anie.200906188
SN - 1433-7851
SN - 1521-3773
SN - 0570-0833
VL - 49
IS - 7
SP - 1258
EP - 1262
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-21132
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schickert, M.
A1 - Krause, Martin
A1 - Müller, W.
T1 - Ultrasonic Imaging of Concrete Elements Using Reconstruction by Synthetic Aperture Focusing Technique
N2 - Ultrasonic reconstruction by the synthetic aperture focusing technique (SAFT) has a great potential to image concrete elements and detect embedded objects. Its algorithm focuses ultrasonic signals received at many aperture points by coherent superposition, yielding a high-resolution image of the region of interest. Using this approach, several problems caused by the strongly inhomogeneous structure of concrete are diminished, where scattering of transmitted pulses leads to disturbing phenomena such as attenuation and structural noise. This contribution is intended to review the work of the writers on the application of SAFT reconstruction to concrete testing. First, consequences of scattering of ultrasonic waves in concrete are qualitatively explained. Then the use of SAFT is discussed in comparison to traditional A-scan and B-scan techniques. Different reconstruction algorithms and implementations are presented for one-, two-, and three-dimensional SAFT. Pulse-echo measurement systems are described, which are able to acquire large sets of data on linear and planar apertures employing single transducer, transducer array, and scanning laser Doppler vibrometer arrangements. To illustrate the application of the SAFT techniques, examples from laboratory and field experiments are described comprising imaging of back walls, tendon ducts containing faults, layers, and reinforcement in concrete elements.
KW - Imaging techniques
KW - Concrete
KW - Acoustic detection
PY - 2003
DO - https://doi.org/10.1061/(ASCE)0899-1561(2003)15:3(235)
SN - 0899-1561
SN - 1943-5533
IS - May/June
SP - 235
EP - 246
PB - American Society of Civil Engineers
CY - New York, NY
AN - OPUS4-2752
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kolar, J.
A1 - Strlic, M.
A1 - Müller-Hess, D.
A1 - Gruber, A.
A1 - Troschke, K.
A1 - Pentzien, Simone
A1 - Kautek, Wolfgang
T1 - Near-UV and visible pulsed laser interaction with paper
N2 - The applicability of excimer laser at 308 nm and Nd:YAG laser at 532 nm with fluences below 0.86 J/cm2 for cleaning of cellulose and paper materials was evaluated. The extent of degradation of purified cotton cellulose and Fabriano paper after laser treatment as well as after a period of accelerated humid oven ageing was determined by following the changes in the degree of polymerization. While irradiation of paper with the excimer laser at 308 nm results in depolymerization of cellulose accompanied by a decrease in ISO brightness, no detrimental effects of Nd:YAG laser treatments were observed.
PY - 2000
DO - https://doi.org/10.1016/S1296-2074(00)00149-7
SN - 1296-2074
SN - 1778-3674
VL - 1
IS - sup.1
SP - 221
EP - 224
PB - Elsevier
CY - Paris
AN - OPUS4-5979
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schmelzer, J.W.P.
A1 - Potapov, O. V.
A1 - Fokin, V. M.
A1 - Müller, Ralf
A1 - Reinsch, Stefan
T1 - The effect of elastic stress and relaxation on crystal nucleation in lithium disilicate glass
N2 - In the framework of a general theoretical approach recently developed, the effect of elastic stresses on the rate of nucleation of crystallites of critical sizes in the process of crystallization of lithium disilicate glasses is studied. Hereby both the evolution of elastic stresses due to changes in the specific volume of the crystallizing system (i.e., differences in the densities of the melt and the crystal) and their relaxation connected with viscous flow are taken into consideration. If the classical theory of nucleation is employed for the determination of the nucleation rates (modified by taking into account elastic stresses), elastic stresses may lead, for the system under consideration, to a decrease of the nucleation rate by up to two orders of magnitude. As shown, the theory allows an at least qualitatively correct incorporation of the effect of elastic stresses and stress relaxation into the description of nucleation phenomena in glass-forming melts.
PY - 2004
DO - https://doi.org/10.1016/j.jnoncrysol.2003.10.002
SN - 0022-3093
VL - 333
IS - 2
SP - 150
EP - 160
PB - North-Holland Publ. Co.
CY - Amsterdam
AN - OPUS4-6236
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Marzok, Ulrich
A1 - Müller, Ralf
A1 - Schadrack, Reinhard
A1 - Krauhausen, M.
A1 - Burgstedt, F.
A1 - Brode, W.
A1 - Reetz, R.
T1 - Hochtemperatur-Laserprofilometrie an keramischen Bauteilen
N2 - Hochleistungssinterwerkstoffe spielen eine wachsende Rolle in derzeitigen Schlüsseltechnologien wie der Mikrosystem-, Informations-, Kommunikations- und Medizintechnik.
Dabei steigen die Anforderungen an die präzise Steuerung der Sinterung. Besonders für komplexe, gradierte oder heterogen zusammengesetzte Formkörper wie zum Beispiel keramische LTCC-Multilayer für die Mikrosystemtechnik hat die exakte Beherrschung dieses Prozessschrittes wesentlichen Einfluss auf die Maßhaltigkeit, mechanische Integrität und Zuverlässigkeit der gesinterten Bauteile. Bedingt durch die Heterogenität der mehrlagigen und mit Leit- und anderen Funktionspasten bedruckten Sinterkörper hinsichtlich ihrer sinterphysikalischen oder thermischen Eigenschaften können bleibende
oder temporäre Verwerfungen beim Schrumpfungsprozess auftreten, wobei letztere unter Umständen Ursache latenter Fehler im späteren Bauteil sind.
PY - 2013
SN - 0173-9913
SN - 0196-6219
VL - 90
IS - 3
SP - D19
EP - D24
PB - Göller
CY - Baden-Baden
AN - OPUS4-28013
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Berger, Georg
A1 - Ploska, Ute
A1 - Gross, U.
A1 - Mesgarian, M.
A1 - Müller-Mai, Ch.
A1 - Voigt, C.
T1 - Tissue response in the femur of rabbits after implantation of a new calcium titanium phosphate composition
KW - Bone Bonding
KW - Calcium Titanium Phosphate
KW - Coated Implants
KW - Tissue Response
PY - 2001
SN - 1013-9826
VL - 192-195
SP - 383
EP - 386
PB - Trans Tech Publ.
CY - Aedermannsdorf
AN - OPUS4-1044
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Busch, R.
A1 - Tielemann, Christopher
A1 - Reinsch, Stefan
A1 - Müller, Ralf
A1 - Patzig, C.
A1 - Krause, M.
A1 - Höche, T.
T1 - Sample preparation for analytical scanning electron microscopy using initial notch sectioning
N2 - A novel method for broad ion beam based sample sectioning using the concept of initial notches is presented. An adapted sample geometry is utilized in order to create terraces with a well-define d step in erosion depth from the surface. The method consists of milling a notch into the surface, followed by glancing-angle ion beam erosion, which leads to preferential erosion at the notch due to increased local surface elevation. The process of terrace formation can be utilized in sample preparation for analytical scanning electron microscopy in order to get efficient access to the depth-dependent microstructure of a material. It is demonstrated that the method can be applied to both conducting and non-conducting specimens. Furthermore, experimental parameters influencing the preparation success are determined. Finally, as a proof-of-concept, an electron backscatter diffraction study on a surface crystallized diopside glass ceramic is performed, where the method is used to analyze orientation dependent crystal growth phenomena occurring during growth of surface crystals into the bulk.
KW - 3D etching
KW - Ion beam erosion Sectioning
KW - EBSD
KW - Sample preparation
KW - Analytical scanning electron microscopy
KW - SEM
KW - Glass Ceramic
KW - Glass
KW - Diopsid
PY - 2021
DO - https://doi.org/10.1016/j.micron.2021.103090
SN - 0968-4328
VL - 150
PB - Elsevier B.V.
AN - OPUS4-53075
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, Ralf
A1 - Prado, M. O.
A1 - Zanotto, E. D.
T1 - Model for sintering polydispersed glass particles
N2 - We propose a model to describe the sintering kinetics of polydispersed glass particles, having no adjustable parameter. The model is based on three sintering stages: a pure Frenkel' (F) first step, a mixed Frenkel/MackenzieShuttleworth' stage, and a third, pure MackenzieShuttleworth' (MS) step. The model considers sample shrinkage as the sum of the partial shrinkage of several clusters, each consisting of equally sized particles and each showing independent F or MS behavior. The overall set of clusters mimics the specimen's real particle size distribution. We then introduce the concept of neck forming ability, which allows the formation of necks among particles of different sizes, relaxing the clustering condition. Using experimental physical parameters: particle size distribution, viscosity, surface energy, and the theoretical neck forming ability, the model describes well the sintering kinetics of an alumino-borosilicate glass powder having polydispersed, irregular shaped particles in a variety of temperatures. The sintering kinetics of the real powder is slower, but not far from the calculated kinetics of a monodispersed distribution containing only particles of average size. Thus the model provides a tool for estimating the sintering kinetics of real glass powders, for any size distribution and temperature, thus minimizing the number of laboratory experiments.
PY - 2001
DO - https://doi.org/10.1016/S0022-3093(00)00399-9
SN - 0022-3093
VL - 279
IS - 2-3
SP - 169
EP - 178
PB - North-Holland Publ. Co.
CY - Amsterdam
AN - OPUS4-935
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kirilina, E.
A1 - Helbling, S.
A1 - Morawski, M.
A1 - Pine, K.
A1 - Reimann, K.
A1 - Jankuhn, S.
A1 - Dinse, J.
A1 - Deistung, A.
A1 - Reichenbach, J. R.
A1 - Trampel, R.
A1 - Geyer, S.
A1 - Müller, Larissa
A1 - Jakubowski, Norbert
A1 - Arendt, T.
A1 - Bazin, P.-L.
A1 - Weiskopf, N.
T1 - Superficial white matter imaging: Contrast mechanisms and whole-brain in vivo mapping
N2 - Superficial white matter (SWM) contains the most cortico-cortical white matter connections in the human brain encompassing the short U-shaped association fibers. Despite its importance for brain connectivity, very little is known about SWM in humans, mainly due to the lack of noninvasive imaging methods. Here, we lay the groundwork for systematic in vivo SWM mapping using ultrahigh resolution 7 T magnetic resonance imaging. Using biophysical modeling informed by quantitative ion beam microscopy on postmortem brain tissue, we demonstrate that MR contrast in SWM is driven by iron and can be linked to the microscopic iron distribution. Higher SWM iron concentrations were observed in U-fiber–rich frontal, temporal, and parietal areas, potentially reflecting high fiber density or late myelination in these areas. Our SWM mapping approach provides the foundation for systematic studies of interindividual differences, plasticity, and pathologies of this crucial structure for cortico-cortical connectivity in humans.
KW - Magnetic resonance imaging
KW - Laser ablation
KW - ICP-MS
KW - Brain
KW - Imaging
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-514430
DO - https://doi.org/10.1126/sciadv.aaz9281
SN - 2375-2548
VL - 6
IS - 41
SP - eaaz9281
PB - American Association for the Advancement of Science (Science/AAAS)
CY - Washington, DC, USA
AN - OPUS4-51443
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Massiot, D.
A1 - Müller, D.
A1 - Hübert, Thomas
A1 - Schneider, M.
A1 - Kentgens, A.
A1 - Coté, B.
A1 - Coutures, J.
A1 - Gessner, W.
T1 - Double rotation and magic-angle spinning nuclear magnetic resonance study of 27Al: reexamination of the aluminium borate 9Al2O3 · 2B2O3
N2 - 27Al nuclear magnetic resonance spectra of polycrystalline aluminium borate 9Al2O3 · 2B2O3 have been measured in double rotation at 11.7 and 7.0 T and high-speed magic-angle spinning at 7.0, 9.4, 11.7, 14.1 and 17.6 T. Spinning sidebands from the satellite transitions were observed at 7.0 and 14.1 T. Each of the four structural aluminium sites [Al(IV), Al(V)(1), Al(V)(2) and Al(VI)] are observed, characterised and assigned in the spectra. The obtained parameter set gives a fully consistent interpretation in agreement with the crystal structure of the compound.
KW - Aluminium
KW - Kernresonanz, magnetisch
KW - Winkel, magisch
KW - Doppelrotation
PY - 1995
DO - https://doi.org/10.1016/0926-2040(95)00021-H
SN - 0926-2040
SN - 1527-3326
VL - 5
IS - 2
SP - 175
EP - 180
PB - Academ. Press
CY - Orlando, Fla.
AN - OPUS4-639
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Jaeger, Carsten
A1 - Ritter, D.
A1 - Goeritzer, M.
A1 - Thiele, A.
A1 - Blumrich, A.
A1 - Beyhoff, N.
A1 - Luettges, K.
A1 - Smeir, E.
A1 - Kasch, J.
A1 - Grune, J.
A1 - Müller, O.
A1 - Klopfleisch, R.
A1 - Foryst-Ludwig, A.
A1 - Kintscher, U.
T1 - Liver X Receptor Agonist AZ876 Induces Beneficial Endogenous Cardiac Lipid Reprogramming and Protects Against Isoproterenol-Induced Cardiac Damage
N2 - Background - It is known that dietary intake of polyunsaturated fatty acids may improve cardiac function. However, relatively high daily doses are required to achieve sufficient cardiac concentrations of beneficial omega‐3 fatty acids. The liver X receptor (LXR) is a nuclear hormone receptor and a crucial regulator of lipid homeostasis in mammals. LXR activation has been shown to endogenously reprogram cellular lipid profiles toward increased polyunsaturated fatty acids levels. Here we studied whether LXR lipid reprogramming occurs in cardiac tissue and exerts cardioprotective actions.
Methods and Results - Male 129SV mice were treated with the LXR agonist AZ876 (20 µmol/kg per day) for 11 days. From day 6, the mice were injected with the nonselective β‐agonist isoproterenol for 4 consecutive days to induce diastolic dysfunction and subendocardial fibrosis while maintaining systolic function. Treatment with isoproterenol led to a marked impairment of global longitudinal strain and the E/e' ratio of transmitral flow to mitral annular velocity, which were both significantly improved by the LXR agonist. Histological examination showed a significant reduction in isoproterenol‐induced subendocardial fibrosis by AZ876. Analysis of the cardiac lipid composition by liquid chromatography‐high resolution mass spectrometry revealed a significant increase in cardiac polyunsaturated fatty acids levels and a significant reduction in saturated fatty acids by AZ876.
Conclusions - The present study provides evidence that the LXR agonist AZ876 prevents subendocardial damage, improves global longitudinal strain and E/e' in a mouse model of isoproterenol‐induced cardiac damage, accompanied by an upregulation of cardiac polyunsaturated fatty acids levels. Cardiac LXR activation and beneficial endogenous cardiac lipid reprogramming may provide a new therapeutic strategy in cardiac disease with diastolic dysfunction.
KW - Heart failure
KW - Lipids
KW - Liver X receptor
KW - Diastolic dysfunction
KW - Nuclear receptor
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529352
DO - https://doi.org/10.1161/JAHA.120.019473
VL - 10
IS - 14
SP - e019473
AN - OPUS4-52935
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pan, Z.
A1 - Waurischk, Tina
A1 - Duval, A.
A1 - Müller, Ralf
A1 - Deubener, J.
A1 - Krishnan, N. M. A.
A1 - Wondraczek, K.
A1 - Wondraczek, L.
T1 - Precise Real‐Time Measurement of Liquid Viscosity Using Digital Video Data
N2 - Quantitative knowledge of liquid viscosity is of fundamental importance in many areas of materials synthesis and processing. However, the determination of viscosity often relies on specialized experimental equipment, offline experimentation, or invasive procedures, in particular when required in extreme conditions such as at high temperature, high pressure, and in confined or corrosive environments. Here, this study proposes and validates a fast and simple method that mimics the intuitive perception of liquid flow within a quantitative framework. For this, this study employs digital video observation to derive quantitative values of the shear viscosity of liquids, with high precision and rapid acquisition rates. The technique involves capturing liquid dynamics after minor mechanical stimulation. Processed imaging data are indexed by similarity and referenced to a digital database generated with a finite element model, from which values of viscosity are obtained in line. The approach is tested on water at room temperature and on a high‐temperature glass melt. Covering a viscosity range of four orders of magnitude, both yield convincing agreement with tabulated reference data at low computational cost.
KW - Image analyses
KW - Liquids
KW - Materials discovery
KW - Similarity analyses
KW - Viscosities
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634606
DO - https://doi.org/10.1002/aisy.202500297
SN - 2640-4567
SP - 1
EP - 12
PB - Wiley
AN - OPUS4-63460
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kiefer, P.
A1 - Maiwald, M.
A1 - Deubener, J.
A1 - Balzer, R.
A1 - Behrens, H.
A1 - Waurischk, Tina
A1 - Reinsch, Stefan
A1 - Müller, Ralf
T1 - Automated Analysis of Slow Crack Growth in Hydrous Soda-Lime Silicate Glasses
N2 - To explore the impact of ambient and structural water on static fatigue, the initiation and growth of 3279 Vickers induced median radial cracks were automatically recorded and analyzed. We find that humidity is more efficient in initiating cracks and promoting their growth than water, which is dissolved in the glass structure. In particular for slow crack growth (< 3x10-6 m s-1), tests in dry nitrogen showed a considerable decrease in the crack growth exponent with increasing water content of the glasses. On the other hand, if tests were performed in humid air, the crack growth exponent was independent of the water content of the hydrous glasses, while stress intensity decreased slightly. These observations indicate that water promotes the processes at the crack-tip regardless of its origin. However, ambient water is more efficient.
KW - Indentation fracture toughness
KW - Slow crack growth
KW - Automated analysis
KW - Hydrous glass
KW - Vickers indentation
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-513085
DO - https://doi.org/10.3389/fmats.2020.00268
VL - 7
SP - 268
AN - OPUS4-51308
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Marzok, Ulrich
A1 - Müller, Ralf
A1 - Schadrack, Reinhard
A1 - Krauhausen, M.
A1 - Burgstedt, F.
A1 - Brode, W.
A1 - Reetz, R.
T1 - High-temperature laser profilometry for ceramic tapes
N2 - Advanced ceramics are promising key components for microsystems
engineering, communication Technology and medical engineering.
Driven by steadiiy increasing demands on dimensional accuracy of
components and Integration density, sintering has to be controlled at
an unprecedented degree of precision.
Being most crucial for components of complex shape, graded or heterogeneous-composed parts like LTCC multilayers for microsystems, precise control of sintering has a decisive influence on the dimensional accuracy, mechanical integrity and reliability of sintered components.
Thus, permanent or temporary shape distortions or warping during sintering may result from spatially heterogeneous microstructure and
temperature distribution, e.g. during the co-firing process of green
multilayer Stacks printed with metallization and other functional pastes.
Whereas permanent warping can be easily measured after sintering, temporary warping during firing is more difficult to measure. Nonetheless, this effect may cause latent failures later, which often limit the applicability of ceramic components.
PY - 2013
SN - 0173-9913
SN - 0196-6219
VL - 90
IS - 4
SP - E35
EP - E40
PB - Göller
CY - Baden-Baden
AN - OPUS4-28500
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Müller, Thoralf
A1 - Heyn, Andreas
A1 - Fenker, M.
A1 - Balzer, Martin
T1 - Investigation on defect morphology and corrosion behaviour of TiMgN hard coatings on steel substrate
N2 - Nitride hard coatings, such as Titanium nitride and chromium nitride coatings are widely used for applications focussing on wear protection and decorative purposes. Also these coatings are often applied on low alloyed steel substrates. The inevitable contact of the coated components with the environment through pores and coating defects bears the danger of corrosion of the steel substrate followed by further delamination of the coating and a loss of function of the component. A new attempt to increase the corrosion behaviour of those physically deposited hard coating systems is the implementation of magnesium. The positive effect of magnesium could be verified already electrochemically. Performed experiments on TiMgN have shown that corrosion resistance could drastically improved with increasing Mg content of the TiMgN up to 30 at% compared to steel substrates with applied titanium nitride hard coatings. Besides the clarification of the electrochemical and phenomenological effect of the magnesium on the corrosion behaviour, an additional aim of this work is the investigation of the coating defects, defect morphologies and their influence on the local corrosion behaviour. For this the incorporation of the magnesium and its effects on the coating material, the influence of coating growth related defects and the effect of the coating structure on the corrosion behaviour should be experimental examined by using innovative surface and material analysis methods such as FIB and TEM. Furthermore the evolution of the coating defects should be investigated by combing confocal microscopy with a new developed exposure test method using the electrochemical indication test KorroPad. The function of the KorroPad test, which was developed and patented [1] at the BAM for the detection of corrosion sensitive steel surfaces by indicating dissolution of iron ions [1], allows the detection and identification of critical coating defects for further microscopic investigation. Additional to that the KorroPad test simulates an accelerated exposure test by simultaneous absence of the disadvantages of typical short time exposure test like salt spray tests. Thus it allows a monitoring and analysis of the evolution of the critical coating defects and their influence on the local corrosion behaviour and the overall corrosion mechanisms. The results of this work should contribute to the development of new hard coatings with improved corrosion protection properties and also to a better understanding of the corrosion mechanisms of coated steel substrates.
T2 - EUROCORR 2014 - European corrosion congress
CY - Pisa, Italy
DA - 08.09.2014
KW - Metallic coatings
KW - Cathodic protection
KW - Corrosion
PY - 2014
SN - 978-3-89746-159-8
SP - O
EP - 7473, 384
AN - OPUS4-31482
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Müller, Thoralf
A1 - Burkert, Andreas
A1 - Heyn, A.
A1 - Balzer, Martin
A1 - Fenker, M.
T1 - Investigation on the improved corrosion behavior of TiMgN hard coating on steel substrate
T2 - EUROCORR 2015 - European corrosion congress
CY - Graz, Austria
DA - 06.09.2015
KW - Hard coatings
KW - TiMgN
KW - Corrosion
PY - 2015
SP - paper 11.1_693
AN - OPUS4-34618
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Balzer, R.
A1 - Behrens, H.
A1 - Waurischk, Tina
A1 - Reinsch, Stefan
A1 - Müller, Ralf
A1 - Kiefer, P.
A1 - Deubener, J.
A1 - Fechtelkord, M.
T1 - Water in Alkali Aluminosilicate Glasses
N2 - To understand the influence of water and alkalis on aluminosilicate glasses, three polymerized glasses with varying ratios of Na/K were synthesized [(22. 5-x)Na2O-xK2O-22.5 Al2O3-55 SiO2 with x = 0, 7.5, and 11.25]. Subsequently, these glasses were hydrated (up to 8 wt% H2O) in an internally heated gas pressure vessel. The density of hydrous glasses linearly decreased with water content above 1 wt%, consistent with the partial molar volume of H2O of 12 cm3/mol. Near-infrared spectroscopy revealed that hydroxyl groups are the dominant species at water content of <4 wt%, and molecular water becomes dominating at water content of >5 wt%. The fraction of OH is particularly high in the pure Na-bearing glass compared to the mixed alkali glasses. 27Al magic angle spinning-NMR spectroscopy shows that aluminum is exclusively fourfold coordinated with some variations in the local geometry. It appears that the local structure around Al becomes more ordered with increasing K/Na ratio. The incorporation of H2O reinforces this effect. The differential thermal analysis of hydrous glasses shows a significant mass loss in the range of glass transition already during the first upscan, implying the high mobility of water in the glasses. This observation can be explained by the open structure of the aluminosilicate network and by the low dissociation enthalpy of H2O in the glasses (≈ 8 kJ/mol). The effect of the dissolved H2O on the glass transition temperature is less pronounced than for other aluminosilicate glasses, probably because of the large fraction of Al in the glasses.
KW - NMR spectroscopy
KW - Alkali aluminosilicate glasses
KW - Water speciation
KW - Glass transition
KW - Infrared spectroscopy
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509497
DO - https://doi.org/10.3389/fmats.2020.00085
VL - 7
SP - 85
AN - OPUS4-50949
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Denißen, M.
A1 - Hannen, R.
A1 - Itskalov, D.
A1 - Biesen, L.
A1 - Nirmalananthan-Budau, Nithiya
A1 - Hoffmann, Katrin
A1 - Reiss, G. J.
A1 - Resch-Genger, Ute
A1 - Müller, T. J. J.
T1 - One-pot synthesis of a white-light emissive bichromophore operated by aggregation-induced dual emission (AIDE) and partial energy transfer
N2 - Merocyanine–triarylamine bichromophores are readily synthesized by sequentially Pd-catalyzed insertion alkynylation–Michael–Suzuki four-component reactions. White-light emissive systems form upon aggregation in 1 : 99 and 0.1 : 99.9 vol% CH2Cl2–cyclohexane mixtures, ascribed to aggregation-induced dual emission (AIDE) in combination with partial energy transfer between both chromophore units as supported by spectroscopic studies.
KW - Energy transfer
KW - Nano
KW - Nanoparticle
KW - Photoluminescence
KW - Fluorescence
KW - Quantum yield
KW - Photophysics
KW - Lifetime
KW - Sensor
KW - Dye
KW - Enhancement
KW - Particle
KW - Polarity
KW - AIE
KW - Aggregation
KW - Aggregation-induced emission
KW - Solid state emission
KW - Merocyanine
PY - 2020
DO - https://doi.org/10.1039/d0cc03451g
VL - 56
IS - 54
SP - 7407
PB - Royal Society of Chemistry
AN - OPUS4-50936
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ast, S.
A1 - Fischer, Tobias
A1 - Müller, H.
A1 - Mickler, W.
A1 - Schwichtenberg, M.
A1 - Rurack, Knut
A1 - Holdt, H.-J.
T1 - Integration of the 1,2,3-triazole 'click' motif as a potent signalling element in metal ion responsive fluorescent probes
N2 - In a systematic approach we synthesized a new series of fluorescent probes incorporating donor–acceptor (D-A) substituted 1,2,3-triazoles as conjugative π-linkers between the alkali metal ion receptor N-phenylaza-[18]crown-6 and different fluorophoric groups with different electron-acceptor properties (4-naphthalimide, meso-phenyl-BODIPY and 9-anthracene) and investigated their performance in organic and aqueous environments (physiological conditions). In the charge-transfer (CT) type probes 1, 2 and 7, the fluorescence is almost completely quenched by intramolecular CT (ICT) processes involving charge-separated states. In the presence of Na+ and K+ ICT is interrupted, which resulted in a lighting-up of the fluorescence in acetonitrile. Among the investigated fluoroionophores, compound 7, which contains a 9-anthracenyl moiety as the electron-accepting fluorophore, is the only probe which retains light-up features in water and works as a highly K+/Na+-selective probe under simulated physiological conditions. Virtually decoupled BODIPY-based 6 and photoinduced electron transfer (PET) type probes 3–5, where the 10-substituted anthracen-9-yl fluorophores are connected to the 1,2,3-triazole through a methylene spacer, show strong ion-induced fluorescence enhancement in acetonitrile, but not under physiological conditions. Electrochemical studies and theoretical calculations were used to assess and support the underlying mechanisms for the new ICT and PET 1,2,3-triazole fluoroionophores.
KW - Charge transfer
KW - Click chemistry
KW - Electron transfer
KW - Fluorescent probes
KW - Metal ions
PY - 2013
DO - https://doi.org/10.1002/chem.201201575
SN - 0947-6539
SN - 1521-3765
VL - 19
IS - 9
SP - 2990
EP - 3005
PB - Wiley-VCH Verl.
CY - Weinheim
AN - OPUS4-27742
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, Bernd R.
A1 - Görner, Wolf
A1 - Hentschel, Manfred P.
A1 - Riesemeier, Heinrich
A1 - Krumrey, M.
A1 - Ulm, G.
A1 - Diete, W.
A1 - Klein, U.
A1 - Frahm, R.
T1 - BAMlin - the first hard X-ray beamline at BESSY II
N2 - The first hard X-ray beamline at BESSY II will be installed by BAM and PTB at a superconducting 7 T wavelength shifter. The main optical elements of the beamline are a Double-Multilayer-Monochromator and a Double-Crystal-Monochromator. The two devices can be used separately or in-line. Main applications of monochromatic radiation with photon energies up to 50 keV are X-ray fluorescence analysis, micro-computed tomography, X-ray topography, detector calibration and reflectometry. Calculable undispersed radiation up to 200 keV will be available for radiometric applications.
KW - Double-Multilayer-Monochromator with meridional bender
KW - Double-Crystal-Monochromator with sagittal bender
KW - X-ray fluorescence analysis
KW - Micro-computed tomography
KW - X-ray topography
KW - Detector calibration
KW - Reflectometry
PY - 2001
DO - https://doi.org/10.1016/S0168-9002(01)00466-1
SN - 0168-9002
SN - 0167-5087
VL - 467-468
IS - 1
SP - 703
EP - 706
PB - North-Holland
CY - Amsterdam
AN - OPUS4-1171
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Herzel, Hannes
A1 - Dombinov, V.
A1 - Vogel, Christian
A1 - Willbold, S.
A1 - Levandowski, G. V.
A1 - Meiller, M.
A1 - Müller, F.
A1 - Zang, J. W.
A1 - da Fonseca-Zang, W. A.
A1 - Jablonowski, N. D.
A1 - Schrey, S. D.
A1 - Adam, Christian
T1 - Soybean Fertilized by P-Phases from Bagasse-Based Materials: P-Extraction Procedures, Diffusive Gradients in Thin Films (DGT), and X-ray Diffraction Analysis (XRD)
N2 - The Brazilian sugarcane industry produced around 173 million tons (Mt) of bagasse in 2018. Bagasse is a by-product of juice extraction for ethanol and sugar production and is combusted in order to generate power, producing up to 10 Mt of ash per year. This ash contains various concentrations of plant nutrients, which allow the ash to be used as a crop fertilizer. However, the concentration and extractability of phosphorus (P), an essential plant nutrient, are low in bagasse ash. To increase the P content, we co-gasified and co-combusted bagasse with P-rich chicken manure. The resulting ash was thermochemically post-treated with alkali additives (Na2SO4 and K2SO4) to increase the availability of P to plants. We aimed to: (i) investigate the effect of thermochemical post-treatment of co-gasification residue and co-combustion ash on P availability to soybeans, (ii) explore the potential of chemical extraction methods (citric acid, neutral ammonium citrate, formic acid, and Mehlich-I) and diffusive gradients in thin films (DGT) to predict the availability of P to soybeans, and (iii) identify the responsible P-phases using X-ray diffraction . We evaluated P availability to soybeans growing in Brazilian Oxisol soil in two independent greenhouse pot experiments. The positive effect of thermochemical treatment on P availability from gasification residue was confirmed through the observation of increased P uptake and biomass in soybean plants. These findings were confirmed by chemical extraction methods and DGT. The gasification residue contained whitlockite as its main P-bearing phase. Thermochemical post-treatment converted whitlockite into highly soluble CaNaPO4. In contrast, co-combustion ash already contained highly soluble Ca(Na,K)PO4 as its main P-bearing phase, making thermochemical post-treatment unnecessary for increasing P availability. In conclusion, increased extractability and availability of P for soybeans were closely connected to the formation of calcium alkali phosphate. Our findings indicate that this combined methodology allows for the prediction of P-fertilization effects of ash.
KW - Sugar cane bagasse
KW - Chicken manure ash
KW - Thermochemical treatment
KW - Nutrient
KW - Plant availability
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509735
DO - https://doi.org/10.3390/agronomy10060895
VL - 10
SP - 895
EP - 6
PB - MDPI
AN - OPUS4-50973
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Markötter, Henning
A1 - Manke, I.
A1 - Haußmann, J.
A1 - Arlt, Tobias
A1 - Klages, M.
A1 - Krüger, P.
A1 - Hartnig, C.
A1 - Scholta, J.
A1 - Müller, Bernd R.
A1 - Riesemeier, Heinrich
A1 - Banhart, J.
T1 - Combined synchrotron X-ray radiography and tomography study of water transport in gas diffusion layers
N2 - Synchrotron X-ray radiography and tomography investigations of a custom-made polymer electrolyte membrane fuel cell optimised for visualisation purposes are presented. The 3D water distribution and transport pathways in the porous carbon fibre gas diffusion layers (GDLs) were investigated. The authors found that water is not only moving from the GDL into the channel, but can also take the opposite way, that is, from the channel into free pore space of the GDL. Such movement of water into the opposite direction has been subject of speculations but has so far not yet been reported and might bring new insights into the general water transport behaviour, which might give new aspects to the general description of water transport processes and influence modelling assumptions to describe the process taking place in the GDL.
KW - Synchrotron radiography
KW - Synchrotron tomography
KW - Gas diffusion layers
KW - Water transport
PY - 2012
DO - https://doi.org/10.1049/mnl.2012.0410
SN - 1750-0443
VL - 7
IS - 7
SP - 689
EP - 692
PB - IET
CY - London
AN - OPUS4-26282
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dombinov, V.
A1 - Herzel, Hannes
A1 - Meiller, M.
A1 - Müller, F.
A1 - Willbold, S.
A1 - Zang, J. W.
A1 - da Fonseca-Zang, W. A.
A1 - Adam, Christian
A1 - Klose, H.
A1 - Poorter, H.
A1 - Jablonowski, N. D.
A1 - Schrey, S. D.
T1 - Sugarcane bagasse ash as fertilizer for soybeans: Effects of added residues on ash composition, mineralogy, phosphorus extractability and plant availability
N2 - Sugarcane bagasse is commonly combusted to generate energy. Unfortunately, recycling strategies rarely consider the resulting ash as a potential fertilizer. To evaluate this recycling strategy for a sustainable circular economy, we characterized bagasse ash as a fertilizer and measured the effects of co-gasification and co-combustion of bagasse with either chicken manure or sewage sludge: on the phosphorus (P) mass fraction, P-extractability, and mineral P phases. Furthermore, we investigated the ashes as fertilizer for soybeans under greenhouse conditions. All methods in combination are reliable indicators helping to assess and predict P availability from ashes to soybeans. The fertilizer efficiency of pure bagasse ash increased with the ash amount supplied to the substrate. Nevertheless, it was not as effective as fertilization with triple-superphosphate and K2SO4, which we attributed to lower P availability. Co-gasification and co-combustion increased the P mass fraction in all bagasse-based ashes, but its extractability and availability to soybeans increased only when co-processed with chicken manure, because it enabled the formation of readily available Ca-alkali phosphates. Therefore, we recommend co-combusting biomass with alkali-rich residues to increase the availability of P from the ash to plants.
KW - Combustion and gasification
KW - Phosphate extractability and availability
KW - X-ray diffraction (XRD)
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567632
DO - https://doi.org/10.3389/fpls.2022.1041924
SN - 1664-462X
VL - 13
SP - 1
EP - 13
PB - Frontiers Media
CY - Lausanne
AN - OPUS4-56763
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lackmann, C.
A1 - Velki, M.
A1 - Šimić, A.
A1 - Müller, Axel
A1 - Braun, U.
A1 - Ečimović, S.
A1 - Hollert, H.
T1 - Two types of microplastics (polystyrene-HBCD and car tire abrasion) affect oxidative stress-related biomarkers in earthworm Eisenia andrei in a time-dependent manner
N2 - Microplastics are small plastic fragments that are widely distributed in marine and terrestrial environments. While the soil ecosystem represents a large reservoir for plastic, research so far has focused mainly on the impact on aquatic ecosystems and there is a lack of information on the potentially adverse effects of microplastics on soil biota. Earthworms are key organisms of the soil ecosystem and are due to their crucial role in soil quality and fertility a suitable and popular model organism in soil ecotoxicology.
Therefore, the aim of this study was to gain insight into the effects of environmentally relevant concentrations of microplastics on the earthworm Eisenia andrei on multiple levels of biological organization after different exposure periods. Earthworms were exposed to two types of microplastics: (1) polystyrene-HBCD and (2) car tire abrasion in natural soil for 2, 7, 14 and 28 d. Acute and chronic toxicity and all subcellular investigations were conducted for all exposure times, avoidance behavior assessed after 48 h and reproduction after 28 d. Subcellular endpoints included enzymatic biomarker responses, namely, carboxylesterase, glutathione peroxidase, acetylcholinesterase, glutathione reductase, glutathione S-transferase and catalase activities, as well as fluorescence-based measurements of oxidative stress-related markers and multixenobiotic resistance activity. Multiple biomarkers showed significant changes in activity, but a recovery of most enzymatic activities could be observed after 28 d. Overall, only minor effects could be observed on a subcellular level, showing that in this exposure scenario with environmentally relevant concentrations based on German pollution levels the threat to soil biota is minimal. However, in areas with higher concentrations of microplastics in the environment, these results can be interpreted as an early warning signal for more adverse effects. In conclusion, these findings provide new insights regarding the ecotoxicological effects of environmentally relevant concentrations of microplastics on soil organisms.
KW - Microplastics
KW - Earthworms
KW - Toxicity
KW - Biomarker
KW - oxidative stress
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545423
DO - https://doi.org/10.1016/j.envint.2022.107190
VL - 163
SP - 1
EP - 12
PB - Elsevier Ltd.
AN - OPUS4-54542
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, P.
A1 - Mielke, Johannes
A1 - Hodoroaba, Vasile-Dan
A1 - Kägi, R.
A1 - Ryner, M.
T1 - Assessment of different electron microscopy techniques for particle size quantification of potential nanomaterials
N2 - While nano-scaled intermediate and consumer products are omnipresent in many industries, one challenge consists in the development of methods that reliably identify, characterize and quantify nanomaterials both as a substance and in various matrices. For product registration purposes, the European Commission proposed a definition for nanomaterial which requires a quantitative size determination of the primary particles in a sample down to sizes of 1 nm. According to a material is defined as nano if 50% of the primary particles are observed to comprise a smallest dimension <100 nm. The NanoDefine project was set up to develop and validate a robust, readily implementable and cost-effective measurement approach to obtain a quantitative particle size distribution and to distinguish between nano and non-nano materials according to the definition Among the available particle sizing techniques, electron microscopy was found to be one option meeting most of the requirements of the regulation. However, the use of electron microscopy for particle sizing is often limited by cost per sample, availability in industry, particle agglomeration/aggregation, extremely broad size distributions, 2D materials and operator bias in case of manual evaluation.
PY - 2015
DO - https://doi.org/10.1017/S1431927615012799
SN - 1431-9276
SN - 1435-8115
VL - 21
IS - Suppl. 3
SP - Paper 1200, 2403
EP - 2404
PB - Cambridge University Press
CY - New York, NY
AN - OPUS4-34922
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Liens, A.
A1 - Reveron, H.
A1 - Douillard, T.
A1 - Blanchard, N.
A1 - Lughi, V.
A1 - Sergo, V.
A1 - Laquai, René
A1 - Müller, Bernd R.
A1 - Bruno, Giovanni
A1 - Schomer, S.
A1 - Fürderer, T.
A1 - Adolfsson, E.
A1 - Courtois, N.
A1 - Swain, M.
A1 - Chevalier, J.
T1 - Phase transformation induces plasticity with negligible damage in ceria-stabilized zirconia-based ceramics
N2 - Ceramics and their composites are in general brittle materials because they are predominantly made up of ionic and covalent bonds that avoid dislocation motion at room temperature. However, a remarkable ductile behavior has been observed on newly developed 11 mol.% ceria-stabilized zirconia (11Ce-TZP) composite containing fine alumina (8 vol.% Al2O3) and elongated strontium hexa-aluminate (8 vol.% SrAl12O19) grains. The as-synthesized composite also has shown full resistance to Low Temperature Degradation (LTD), relatively high strength and exceptionally high Weibull modulus, allowing its use in a broader range of biomedical applications. In this study, to deepen the understanding of plastic deformation in Ce-TZP based composites that could soon be used for manufacturing dental implants, different mechanical tests were applied on the material, followed by complete microstructural characterization. Distinct from pure Ce-TZP material or other zirconia-based ceramics developed in the past, the material here studied can be permanently strained without affecting the Young modulus, indicating that the ductile response of tested samples cannot be associated to damage occurrence. This ductility is related to the stress-induced tetragonal to monoclinic (t-m) zirconia phase transformation, analogue to Transformation-Induced Plasticity (TRIP) steels, where retained austenite is transformed to martensite. The aim of this study is to corroborate if the observed plasticity can be associated exclusively to the zirconia t-m phase transformation, or also to microcraking induced by the transformation. The t-m transformed-zones produced after bending and biaxial tests were examined by X-ray refraction and SEM/TEM coupled with Raman. The results revealed that the observed elastic-plastic behavior occurs without extensive microcracking, confirming a purely elastic-plastic behavior driven by the phase transformation (absence of damage).
KW - Zirconia
KW - Ceria
KW - Ceramic matrix composite
KW - Plasticity
KW - Phase transformation
KW - X-Ray Refraction
PY - 2020
UR - http://www.sciencedirect.com/science/article/pii/S1359645419307177
DO - https://doi.org/10.1016/j.actamat.2019.10.046
SN - 1359-6454
VL - 183
SP - 261
EP - 273
PB - Elsevier Ltd.
AN - OPUS4-49740
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Laquai, René
A1 - Gouraud, F.
A1 - Müller, Bernd R.
A1 - Huger, M.
A1 - Chotard, T.
A1 - Antou, G.
A1 - Bruno, Giovanni
T1 - Evolution of Thermal Microcracking in Refractory ZrO2-SiO2 after Application of External Loads at High Temperatures
N2 - Zirconia-based cast refractories are widely used for glass furnace applications. Since they have to withstand harsh chemical as well as thermo-mechanical environments, internal stresses and microcracking are often present in such materials under operating conditions (sometimes in excess of 1700 °C). We studied the evolution of thermal (CTE) and mechanical (Young’s modulus) properties as a function of temperature in a fused-cast refractory containing 94 wt.% of monoclinic ZrO2 and 6 wt.% of a silicate glassy phase. With the aid of X-ray refraction techniques (yielding the internal specific surface in materials), we also monitored the evolution of microcracking as a function of thermal cycles (crossing the martensitic phase transformation around 1000 °C) under externally applied stress. We found that external compressive stress leads to a strong decrease of the internal surface per unit volume, but a tensile load has a similar (though not so strong) effect. In agreement with existing literature on -eucryptite microcracked ceramics, we could explain These phenomena by microcrack closure in the load direction in the compression case, and by microcrack propagation (rather than microcrack nucleation) under tensile conditions.
KW - Electro-fused zirconia
KW - Microcracking
KW - Synchrotron x-ray refraction radiography (SXRR)
KW - Thermal expansion
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-477431
DO - https://doi.org/10.3390/ma12071017
VL - 12
IS - 7
SP - 1
EP - 15
PB - MDPI
AN - OPUS4-47743
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Voss, Heike
A1 - Knigge, Xenia
A1 - Knapic, D.
A1 - Weise, Matthias
A1 - Sahre, Mario
A1 - Hertwig, Andreas
A1 - Sacco, A.
A1 - Rossi, A. M.
A1 - Radnik, Jörg
A1 - Müller, Kai
A1 - Wasmuth, Karsten
A1 - Krüger, Jörg
A1 - Hassel, A. W.
A1 - Hodoroaba, Vasile-Dan
A1 - Bonse, Jörn
T1 - Picosecond laser processing of hierarchical micro–nanostructures on titanium alloy upon pre- and postanodization: morphological, structural, and chemical effects
N2 - Recent publications indicate that the order of electrochemical anodization (before or after the laser processing step) plays an important role for the response of bone-forming osteoblasts—an effect that can be utilized for improving permanent dental or removable bone implants. For exploring these different surface functionalities, multimethod morphological, structural, and chemical characterizations are performed in combination with electrochemical pre- and postanodization for two different characteristic microspikes covered by nanometric laser-induced periodic surface structures on Ti–6Al–4V upon irradiation with near-infrared ps-laser pulses (1030 nm wavelength, ≈1 ps pulse duration, 67 and 80 kHz pulse repetition frequency) at two distinct sets of laser fluence and beam scanning parameters. This work involves morphological and topographical investigations by scanning electron microscopy and white light interference microscopy, structural material examinations via X-ray diffraction, and micro-Raman spectroscopy, as well as near-surface chemical analyses by X-ray photoelectron spectroscopy and hard X-ray photoelectron spectroscopy. The results allow to qualify the mean laser ablation depth, assess the spike geometry and surface roughness parameters, and provide new detailed insights into the near-surface oxidation that may affect the different cell growth behavior for pre- or postanodized medical implants.
T2 - 2023 E-MRS Spring Meeting, Symposium L "Making light matter: lasers in material sciences and photonics"
CY - Strasbourg, France
DA - 29.05.2023
KW - Hierarchical micro-nanostructures
KW - Laser-induced periodic surface structures (LIPSS)
KW - Ultrashort laser pulses
KW - Ti-6Al-4V alloy
KW - X-ray photoelectron spectroscopy
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601962
DO - https://doi.org/10.1002/pssa.202300920
SN - 1862-6319
SP - 1
EP - 11
PB - Wiley-VCH GmbH
CY - Weinheim
AN - OPUS4-60196
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Brüngel, R.
A1 - Rückert, J.
A1 - Müller, P.
A1 - Babick, F.
A1 - Friedrich, C. M.
A1 - Ghanem, A.
A1 - Hodoroaba, Vasile-Dan
A1 - Mech, A.
A1 - Weigel, S.
A1 - Wohlleben, W.
A1 - Rauscher, H.
T1 - NanoDefiner Framework and e-Tool Revisited According to the European Commission’s Nanomaterial Definition 2022/C 229/01
N2 - The new recommended definition of a nanomaterial, 2022/C 229/01, adopted by the European Commission in 2022, will have a considerable impact on European Union legislation addressing chemicals, and therefore tools to implement this new definition are urgently needed. The updated NanoDefiner framework and its e-tool implementation presented here are such instruments, which help stakeholders to find out in a straightforward way whether a material is a nanomaterial or not. They are two major outcomes of the NanoDefine project, which is explicitly referred to in the new definition. This work revisits the framework and e-tool, and elaborates necessary adjustments to make these outcomes applicable for the updated recommendation. A broad set of case studies on representative materials confirms the validity of these adjustments. To further foster the sustainability and applicability of the framework and e-tool, measures for the FAIRification of expert knowledge within the e-tool’s knowledge base are elaborated as well. The updated framework and e-tool are now ready to be used in line with the updated recommendation. The presented approach may serve as an example for reviewing existing guidance and tools developed for the previous definition 2011/696/EU, particularly those adopting NanoDefine project outcomes.
KW - Nanomaterial definition
KW - Nanomaterial categorisation
KW - Nanomaterial regulation
KW - Nanomaterial legislation
KW - Decision support
KW - FAIRification
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571618
DO - https://doi.org/10.3390/nano13060990
SN - 2079-4991
VL - 13
IS - 6 - Special Issue "Identification and Quantification of Nanomaterials"
SP - 1
EP - 16
PB - MDPI
CY - Basel, CH
AN - OPUS4-57161
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Baer, D. R.
A1 - Cant, D. J. H.
A1 - Castner, D. G.
A1 - Ceccone, G.
A1 - Engelhard, M. H.
A1 - Karakoti, A. S.
A1 - Müller, Anja
ED - Hodoroaba, Vasile-Dan
ED - Unger, Wolfgang
ED - Shard, A. G.
T1 - Preparation of nanoparticles for surface analysis
N2 - A variety of methods used to prepare nano-objects for surface analysis are described along with information about when they might be best applied. Intrinsic properties of NPs which complicate their characterization and need to be considered when planning for surface or other analyses of NPs are identified, including challenges associated with reproducible synthesis and functionalization of the particles as well as their dynamic nature. The relevant information about the sample preparation processes, along with analysis details and data that need to be added to the collection of material provenance information is identified. Examples of protocols that have been successfully used for preparation of nano-objects for surface analysis are included in an annex.
KW - Sample preparation
KW - Nanoparticles
KW - Surface chemistry
KW - XPS
KW - Dynamic behavior
KW - Nano-object
KW - Surface analysis
PY - 2020
SN - 978-0-12-814182-3
DO - https://doi.org/10.1016/B978-0-12-814182-3.00018-3
SP - 295
EP - 347
PB - Elsevier
CY - Amsterdam
AN - OPUS4-50186
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Balzer, R.
A1 - Behrens, H.
A1 - Schuth, S.
A1 - Waurischk, Tina
A1 - Reinsch, Stefan
A1 - Müller, Ralf
A1 - Fechtelkord, M.
A1 - Deubener, J.
T1 - The influence of H2O and SiO2 on the structure of silicoborate glasses
N2 - To understand the impact of dissolved water on structure and properties, four boron-rich glasses of molar compositions 15-x Na2O x CaO 15 SiO2 70 B2O3 (with x=0, 7.5, 10) and 10 Na2O 15 SiO2 75 B2O3 were prepared and subsequently hydrated (up to 8 wt% H2O). Density measurements show a non-linear trend upon hydration implying large structural changes in particular at water contents<2 wt%. Near-infrared spectroscopy shows hydroxyl groups are the dominant species in all glasses upon the entire range of water content. Molecular H2O is detectable only at total water contents>2 wt%. 11B MAS NMR spectra show that the abundance of BO4 species is mainly controlled by ratio of (Na2O+CaO)/B2O3 while incorporation of water plays a minor role.
Compared to borate glasses, the efficiency of formation of BO4 tetrahedra is favored by crosslinking of the network by SiO4-units. The glass transition temperatures, determined by differential thermal analysis, decreases continuously with water content due to breakage of B-O-B bonds by hydrolysis. However, compared to Silicates and aluminosilicates, the effect of dissolved water is less pronounced which can be explained by weaker B-O-B bonds in comparison to Si-O-Si bonds.
KW - High pressure
KW - Water speciation
KW - Silicoborate glasses
KW - Infrared spectroscopy
KW - NMR spectroscopy
PY - 2019
DO - https://doi.org/10.1016/j.jnoncrysol.2019.05.030
VL - 519
SP - 38
EP - 51
PB - Elsevier B.V.
AN - OPUS4-48748
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, Bernd R.
A1 - Cooper, R.C.
A1 - Lange, Axel
A1 - Kupsch, Andreas
A1 - Wheeler, M.
A1 - Hentschel, Manfred P.
A1 - Staude, Andreas
A1 - Pandey, A.
A1 - Shyam, A.
A1 - Bruno, Giovanni
T1 - Stress-induced microcrack density evolution in β-eucryptite ceramics: Experimental observations and possible route to strain hardening
N2 - In order to investigate their microcracking behaviour, the microstructures of several β-eucryptite ceramics, obtained from glass precursor and cerammed to yield different grain sizes and microcrack densities, were characterized by laboratory and synchrotron x-ray refraction and tomography. Results were compared with those obtained from scanning electron microscopy (SEM). In SEM images, the characterized materials appeared fully dense but computed tomography showed the presence of pore clusters. Uniaxial tensile testing was performed on specimens while strain maps were recorded and analyzed by Digital Image Correlation (DIC). X-ray refraction techniques were applied on specimens before and after tensile testing to measure the amount of the internal specific surface (i.e., area per unit volume). X-ray refraction revealed that (a) the small grain size (SGS) material contained a large specific surface, originating from the grain boundaries and the interfaces of TiO2 precipitates; (b) the medium (MGS) and large grain size (LGS) materials possessed higher amounts of specific surface compared to SGS material due to microcracks, which decreased after tensile loading; (c) the precursor glass had negligible internal surface. The unexpected decrease in the internal surface of MGS and LGS after tensile testing is explained by the presence of compressive regions in the DIC strain maps and further by theoretical arguments. It is suggested that while some microcracks merge via propagation, more close mechanically, thereby explaining the observed X-ray refraction results. The mechanisms proposed would allow the development of a strain hardening route in ceramics.
KW - Beta-eucryptite
KW - Microcracked ceramics
KW - X-ray refraction
KW - Tensile load
KW - Strain hardening
KW - Synchrotron
KW - BAMline
KW - Computed Tomography
KW - CT
PY - 2018
UR - http://www.sciencedirect.com/science/article/pii/S1359645417308881
DO - https://doi.org/10.1016/j.actamat.2017.10.030
SN - 1359-6454
SN - 1873-2453
VL - 144
IS - Supplement C
SP - 627
EP - 641
PB - Elsevier B.V.
AN - OPUS4-43024
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schob, D.
A1 - Sagradov, I.
A1 - Roszak, R.
A1 - Sparr, H.
A1 - Franke, R.
A1 - Ziegenhorn, M.
A1 - Kupsch, Andreas
A1 - Léonard, Fabien
A1 - Müller, Bernd R.
A1 - Bruno, Giovanni
T1 - Experimental determination and numerical simulation of material and damage behaviour of 3D printed polyamide 12 under cyclic loading
N2 - The material and damage behaviour of additively manufactured polyamide 12 under cyclic loading was characterized by cyclic tests and microstructure analysis by using microscopy, X-ray refraction, and computed tomography. The results were used to determine parameters for the viscoplastic material model by Chaboche and a damage model by Gurson-Tvergaard-Needleman. The temperature was monitored during the experiments and the self-heating effect was observed. By including this effect, a higher accuracy could be achieved with the results of mechanical experiments.
KW - 3D printing Polyamide 12
KW - Chaboche model
KW - GTN model
KW - Material and damage behaviour
KW - X-ray refraction
KW - Computed tomography
PY - 2020
DO - https://doi.org/10.1016/j.engfracmech.2019.106841
SN - 0013-7944
VL - 229
SP - 106841-1
EP - 106841-13
PB - Elsevier Ltd.
CY - Amsterdam
AN - OPUS4-50557
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schob, D.
A1 - Roszak, R.
A1 - Sagradov, I.
A1 - Sparr, H.
A1 - Ziegenhorn, M.
A1 - Kupsch, Andreas
A1 - Léonard, Fabien
A1 - Müller, Bernd R.
A1 - Bruno, Giovanni
T1 - Experimental determination and numerical simulation of material and damage behaviour of 3D printed polyamide 12 under quasi-static loading
N2 - In order to characterise the material and damage behaviour of additively manufactured polyamide 12 (PA12) under quasi-static load and to implement it in a numerical model, experiments under quasi-static load as well as microstructural investigations were carried out. Selective laser sintering (SLS) was used as the manufacturing process. For the classification of the material behaviour, quasi-static cyclic tests with holding times as well as tensile tests were performed. X-ray refraction and computed tomography (CT) were used to investigate the damage behaviour. The Chaboche model, which has already been applied for metallic materials under thermomechanical loading, served as the basis for the selection of the numerical material model. The same procedure was used for the selection of the damage model, where the Gurson–Tvergaard–Needleman (GTN) model was chosen, which was already used for porous metallic materials. The Chaboche model shows very good agreement with experimental results. Furthermore, the coupling with the GTN model allows a very good modelling of the damage behaviour. Finally, it could be shown that the selected models are suitable to simulate the material and damage behaviour of 3D printed PA12.
KW - Polyamide 12
KW - 3D printing
KW - Viscoplastic
KW - Chaboche model
KW - Damage
KW - GTN model
KW - X-ray refraction
KW - Computed tomography
PY - 2019
DO - https://doi.org/10.24423/aom.3162
SN - 0373-2029
VL - 71
IS - 4-5
SP - 507
EP - 526
PB - IPPT PAN - Polish Academy of Sciences, Institute of Fundamental Technological Research
CY - Warsaw
AN - OPUS4-49409
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Nellesen, J.
A1 - Laquai, René
A1 - Müller, Bernd R.
A1 - Kupsch, Andreas
A1 - Hentschel, M. P.
A1 - Anar, N. B.
A1 - Soppa, E.
A1 - Tillmann, W.
A1 - Bruno, Giovanni
T1 - In situ analysis of damage evolution in an Al/Al2O3 MMC under tensile load by synchrotron X-ray refraction imaging
N2 - The in situ analysis of the damage evolution in a metal Matrix composite (MMC) using synchrotron X-ray refraction radiography (SXRR) is presented. The investigated material is an Al alloy (6061)/10 vol% Al2O3 MMC after T6 heat treatment.
In an interrupted tensile test the gauge section of dog bone-shaped specimens is imaged in different states of tensile loading. On the basis of the SXRR images, the relative change of the specific surface (proportional to the amount of damage) in the course of tensile loading was analyzed. It could be shown that the damage can be detected by SXRR already at a stage of tensile loading, in which no Observation of damage is possible with radiographic absorption-based imaging methods.
Moreover, the quantitative analysis of the SXRR images reveals that the amount of damage increases homogeneously by an average of 25% with respect to the Initial state. To corroborate the experimental findings, the damage distribution was imaged in 3D after the final tensile loading by synchrotron X-ray refraction computed tomography (SXRCT) and absorption-based synchrotron X-ray computed tomography (SXCT). It could be evidenced that defects and damages cause pronounced indications in the SXRCT images.
KW - Composite materials
KW - Defects
KW - Micro analysis
PY - 2018
DO - https://doi.org/10.1007/s10853-017-1957-x
SN - 0022-2461
SN - 1573-4803
VL - 53
IS - 8
SP - 6021
EP - 6032
PB - Springer US
AN - OPUS4-44241
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tötzke, C.
A1 - Gaiselmann, G.
A1 - Osenberg, M.
A1 - Bohner, J.
A1 - Arlt, Tobias
A1 - Markötter, Henning
A1 - Hilger, A.
A1 - Wieder, F.
A1 - Kupsch, Andreas
A1 - Müller, Bernd R.
A1 - Hentschel, Manfred P.
A1 - Banhart, J.
A1 - Schmidt, V.
A1 - Lehnert, W.
A1 - Manke, I.
T1 - Three-dimensional study of compressed gas diffusion layers using synchrotron X-ray imaging
N2 - We present a synchrotron X-ray tomographic study on the morphology of carbon fiber-based gas diffusion layer (GDL) material under compression. A dedicated compression device is used to provide well-defined compression conditions. A flat compression punch is employed to study the fiber geometry at different degrees of compression. Transport relevant geometrical parameters such as porosity, pore size and tortuosity distributions are calculated. The geometric properties notably change upon compression which has direct impact on transport conditions for gas and fluid flow. The availability of broad 3D paths, which are most important for the transport of liquid water from the catalyst layer through the GDL, is markedly reduced after compression. In a second experiment, we study the influence of the channel-land-pattern of the flow-field on shape and microstructure of the GDL. A flow-field compression punch is employed to reproduce the inhomogeneous compression conditions found during fuel cell assembly. While homogenously compressed underneath the land the GDL is much less and inhomogeneously compressed under the channel. The GDL material extends far into the channel volume where it can considerably influence gas and fluid flow. Loose fiber endings penetrate deeply into the channel and form obstacles for the discharge of liquid water droplets.
KW - Synchrotron X-ray tomography
KW - Gas diffusion layer (GDL)
KW - Microstructure
KW - Water transport path
KW - Pore size analysis
KW - Geometrical tortuosity
PY - 2014
DO - https://doi.org/10.1016/j.jpowsour.2013.12.062
SN - 0378-7753
VL - 253
SP - 123
EP - 131
PB - Elsevier
CY - Amsterdam [u.a.]
AN - OPUS4-29979
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tötzke, C.
A1 - Gaiselmann, G.
A1 - Osenberg, M.
A1 - Arlt, Tobias
A1 - Markötter, Henning
A1 - Hilger, A.
A1 - Kupsch, Andreas
A1 - Müller, Bernd R.
A1 - Schmidt, V.
A1 - Lehnert, W.
A1 - Manke, I.
T1 - Influence of hydrophobic treatment on the structure of compressed gas diffusion layers
N2 - Carbon fiber based felt materials are widely used as gas diffusion layer (GDL) in fuel cells. Their transport properties can be adjusted by adding hydrophobic agents such as polytetrafluoroethylene (PTFE). We present a synchrotron X-ray tomographic study on the felt material Freudenberg H2315 with different PTFE finishing. In this study, we analyze changes in microstructure and shape of GDLs at increasing degree of compression which are related to their specific PTFE load. A dedicated compression device mimicking the channel-land pattern of the flowfield is used to reproduce the inhomogeneous compression found in a fuel cell. Transport relevant geometrical parameters such as porosity, pore size distribution and geometric tortuosity are calculated and consequences for media transport discussed. PTFE finishing results in a marked change of shape of compressed GDLs: surface is smoothed and the invasion of GDL fibers into the flow field channel strongly mitigated. Furthermore, the PTFE impacts the microstructure of the compressed GDL. The number of available wide transport paths is significantly increased as compared to the untreated material. These changes improve the transport capacity liquid water through the GDL and promote the discharge of liquid water droplets from the cell.
KW - Gas diffusion layer
KW - Synchrotron Tomography
KW - Compression
KW - Hydrophobic treatment
KW - Water transport
PY - 2016
DO - https://doi.org/10.1016/j.jpowsour.2016.05.118
SN - 0378-7753
VL - 324
SP - 625
EP - 636
PB - Elsevier
CY - Amsterdam
AN - OPUS4-36918
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wonneberger, R.
A1 - Gräf, S.
A1 - Bonse, Jörn
A1 - Wisniewski, W.
A1 - Freiberg, K.
A1 - Hafermann, M.
A1 - Ronning, C.
A1 - Müller, F. A.
A1 - Undisz, A.
T1 - Tracing the Formation of Femtosecond Laser-Induced Periodic Surface Structures (LIPSS) by Implanted Markers
N2 - The generation of laser-induced periodic surface structures (LIPSS) using femtosecond lasers facilitates the engineering of material surfaces with tailored functional properties. Numerous aspects of their complex formation process are still under debate, despite intensive theoretical and experimental research in recent decades. This particularly concerns the challenge of verifying approaches based on electromagnetic effects or hydrodynamic processes by experiment. In the present study, a marker experiment is designed to conclude on the formation of LIPSS. Well-defined concentration depth profiles of 55Mn+- and 14N+-ions were generated below the polished surface of a cast Mn- and Si-free stainless steel AISI 316L using ion implantation. Before and after LIPSS generation, marker concentration depth profiles and the sample microstructure were evaluated by using transmission electron microscopy techniques. It is shown that LIPSS predominantly formed by material removal through locally varying ablation. Local melting and resolidification with the redistribution of the material occurred to a lesser extent. The experimental design gives quantitative access to the modulation depth with a nanometer resolution and is a promising approach for broader studies of the interactions of laser beams and material surfaces. Tracing LIPSS formation enables to unambiguously identify governing aspects, consequently guiding the path to improved processing regarding reproducibility, periodicity, and alignment.
KW - Laser-induced periodic surface structures (LIPSS)
KW - Femtosecond laser processing
KW - Ion implantation
KW - Transmission Electron Microscopy (TEM)
KW - Stainless steel
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623990
DO - https://doi.org/10.1021/acsami.4c14777
SN - 1944-8244 (Print)
SN - 1944-8252 (Online)
VL - 17
IS - 1
SP - 2462
EP - 2468
PB - ACS Publications
AN - OPUS4-62399
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Reiche, I.
A1 - Muller, K.
A1 - Alberic, M.
A1 - Scharf, O.
A1 - Wahning, A.
A1 - Bjeoumikhov, A.
A1 - Radtke, Martin
A1 - Simon, R.
T1 - Discovering vanished paints and naturally formed gold nanoparticles on 2800 years old Phoenician ivories using SR-FF-microXRF with the color X-ray camera
N2 - Phoenician ivory objects (8th century B.C., Syria) from the collections of the Badisches Landesmuseum, Karlsruhe, Germany, have been studied with full field X-ray fluorescence microimaging, using synchrotron radiation (SR-FF-microXRF). The innovative Color X-ray Camera (CXC), a full-field detection device (SLcam), was used at the X-ray fluorescence beamline of the ANKA synchrotron facility (ANKA-FLUO, KIT, Karlsruhe, Germany) to noninvasively study trace metal distributions at the surface of the archeological ivory objects. The outstanding strength of the imaging technique with the CXC is the capability to record the full XRF spectrum with a spatial resolution of 48 µm on a zone of a size of 11.9 × 12.3 mm² (264 × 264 pixels). For each analyzed region, 69696 spectra were simultaneously recorded. The principal elements detected are P, Ca, and Sr, coming from the ivory material itself; Cu, characteristic of pigments; Fe and Pb, representing sediments or pigments; Mn, revealing deposited soil minerals; Ti, indicating restoration processes or correlated with Fe sediment traces; and Au, linked to a former gilding. This provides essential information for the assessment of the original appearance of the ivory carvings. The determined elemental maps specific of possible pigments are superimposed on one another to visualize their respective distributions and reconstruct the original polychromy and gilding. Reliable hypotheses for the reconstruction of the original polychromy of the carved ivories are postulated on this basis.
KW - SR-FF-microXRF
KW - Elemental imaging
KW - Ivory
KW - Paints
KW - Au NPs
KW - Egyptian blue
KW - Fe
PY - 2013
DO - https://doi.org/10.1021/ac4006167
SN - 0003-2700
SN - 1520-6882
VL - 85
IS - 12
SP - 5857
EP - 5866
PB - American Chemical Society
CY - Washington, DC
AN - OPUS4-30222
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Eichelbaum, M.
A1 - Rademann, K.
A1 - Weigel, W.
A1 - Löchel, B.
A1 - Radtke, Martin
A1 - Müller, Ralf
T1 - Gold-Ruby Glass in a New Light: On the Microstructuring of Optical Glasses with Synchrotron Radiation
KW - Nanoparticles
KW - Glasses
KW - Synchrotron radiation
KW - X-ray lithography
KW - Surface plasmon resonance
KW - Luminescence
PY - 2007
SN - 0017-1557
VL - 40
IS - 4
SP - 1
EP - 5
CY - London
AN - OPUS4-16432
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Riesemeier, Heinrich
A1 - Ecker, Klaus
A1 - Görner, Wolf
A1 - Müller, Bernd R.
A1 - Radtke, Martin
A1 - Krumrey, M.
T1 - Layout and first XRF Applications of the BAMline at BESSY II+
N2 - The first hard x-ray beamline at BESSY II has been installed by BAM and PTB at a superconducting 7 T wavelength shifter. The main optical elements of the beamline are a double-multilayer monochromator and a double-crystal monochromator. Depending on the application, the two devices are used separately or in-line. The main applications of the monochromatic radiation with photon energies up to 60 keV are x-ray fluorescence analysis, micro computed tomography, x-ray topography, detector calibration and reflectometry. Calculable undispersed radiation up to 200 keV is available for radiometric applications.
KW - BAMline
KW - XRF
PY - 2005
DO - https://doi.org/10.1002/xrs.750
SN - 0049-8246
VL - 34
IS - 2
SP - 160
EP - 163
PB - Wiley
CY - Chichester
AN - OPUS4-11929
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Brücher, M.
A1 - von Bohlen, A.
A1 - Jacob, P.
A1 - Franzke, J.
A1 - Radtke, Martin
A1 - Reinholz, Uwe
A1 - Müller, Bernd R.
A1 - Scharf, Oliver
A1 - Hergenröder, R.
T1 - The charge of solid-liquid interfaces measured by X-ray standing waves and streaming current
N2 - Measurements of ion distributions at a charged solid–liquid interface using X-ray standing waves (XSW) are presented. High energy synchrotron radiation (17.48 keV) is used to produce an XSW pattern inside a thin water film on a silicon wafer. The liquid phase is an aqueous solution containing Br and Rb ions. The surface charge is adjusted by titration. Measurements are performed over a pH range from 2.2–9, using the native Si oxide layer and functional (amine) groups as surface charge. The Debye length, indicating the extension of the diffuse layer, could be measured with values varying between 1–4 nm. For functionalized wafers, the pH dependent change from attraction to repulsion of an ion species could be detected, indicating the isoelectric point. In combination with the measurement of the streaming current, the surface charge of the sample could be quantified.
KW - Interfacial charge
KW - Solid/liquid interfaces
KW - Surface analysis
KW - Surface functionalization
KW - X-ray spectrometry
KW - X-ray
KW - Standing waves
KW - XSW
KW - Streaming current
KW - Synchrotron radiation
PY - 2010
DO - https://doi.org/10.1002/cphc.201000166
SN - 1439-4235
SN - 1439-7641
VL - 11
IS - 10
SP - 2118
EP - 2123
PB - Wiley-VCH Verl.
CY - Weinheim
AN - OPUS4-22057
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Buckle, T.
A1 - van der Wal, S.
A1 - van Malderen, S.
A1 - Müller, Larissa
A1 - Kuil, J.
A1 - van Unen, V.
A1 - Peters, R.
A1 - van Bemmel, M.
A1 - McDonnell, L.
A1 - Velders, A.
A1 - Koning, F.
A1 - Vanhaeke, F.
A1 - van Leeuwen, F.
T1 - Hybrid imaging labels: providing the link between mass spectrometry-based molecular pathology and theranostics
N2 - Development of theranostic concepts that include inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS) imaging can be hindered by the lack of a direct comparison to more standardly used methods for in vitro and in vivo evaluation; e.g. fluorescence or nuclear medicine. In this study a bimodal (or rather, hybrid) tracer that contains both a fluorescent dye and a chelate was used to evaluate the existence of a direct link between mass spectrometry (MS) and in vitro and in vivo molecular imaging findings using fluorescence and radioisotopes. At the same time, the hybrid label was used to determine whether the use of a single isotope label would allow for MS-based diagnostics.
KW - Imaging
KW - Laser Ablation ICP-MS
KW - Diagnostics
PY - 2017
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-396813
DO - https://doi.org/10.7150/thno.17484
VL - 7
IS - 3
SP - 624
EP - 633
PB - IvySpring
AN - OPUS4-39681
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, Anja
A1 - Krahl, T.
A1 - Radnik, Jörg
A1 - Wagner, Andreas
A1 - Werner, W. S. M.
A1 - Ritter, B.
A1 - Kemnitz, E.
A1 - Unger, Wolfgang
T1 - Chemical in-depth analysis of (Ca/Sr)F2 core–shell like nanoparticles by X-ray photoelectron spectroscopy with tunable excitation energy
N2 - The fluorolytic sol–gel synthesis is applied with the intention to obtain two different types of core–shell nanoparticles, namely, SrF2–CaF2 and CaF2–SrF2. In two separate fluorination steps for core and shell formation, the corresponding metal lactates are reacted with anhydrous HF in ethylene glycol. Scanning transmission electron microscopy (STEM) and dynamic light scattering (DLS) confirm the formation of particles with mean dimensions between 6.4 and 11.5 nm. The overall chemical composition of the particles during the different reaction steps is monitored by quantitative Al Kα excitation X-ray photoelectron spectroscopy (XPS). Here, the formation of stoichiometric metal fluorides (MF2) is confirmed, both for the core and the final core–shell particles. Furthermore, an in-depth analysis by synchrotron radiation XPS (SR-XPS) with tunable excitation energy is performed to confirm the core–Shell character of the nanoparticles. Additionally, Ca2p/Sr3d XPS intensity ratio in-Depth profiles are simulated using the software Simulation of Electron Spectra for Surface Analysis (SESSA). In principle, core–shell like particle morphologies are formed but without a sharp interface between calcium and strontium containing phases.
Surprisingly, the in-depth chemical distribution of the two types of nanoparticles is equal within the error of the experiment. Both comprise a SrF2-rich core domain and CaF2-rich shell domain with an intermixing zone between them. Consequently, the internal morphology of the final nanoparticles seems to be independent from the synthesis chronology.
KW - Metal fluorides
KW - Sol-gel synthesis
KW - Synchrotron radiation
KW - X-ray photoelectron spectroscopy
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522284
DO - https://doi.org/10.1002/sia.6937
SN - 0142-2421
VL - 53
IS - 5
SP - 494
EP - 508
PB - Wiley VCH
AN - OPUS4-52228
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, Larissa
A1 - Jakubowski, Norbert
A1 - Hösl, Simone
A1 - Scheler, C.
A1 - Roos, P. H.
A1 - Linscheid, M. W.
T1 - Comparison of different chelates for lanthanide labeling of antibodies and application in a Western blot immunoassay combined with detection by laser ablation (LA-)ICP-MS
N2 - We have developed lanthanide labeling strategies for antibodies to adapt conventional biochemical workflows like Western blot immunoassays for detection by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis with a special interest to apply the multi-element capabilities of ICP-MS for the design of multiplexed immunoassays. In this paper the lanthanide labeling of antibodies with MeCAT was investigated and the reaction conditions were optimized for application in a Western blot immunoassay analyzed by LA-ICP-MS. Furthermore, the MeCAT labeling strategy was compared with two other commercially available labeling reagents, MAXPAR and SCN-DOTA. As a proof-of-principle experiment chemically induced alterations of cytochrome P450 protein expression were investigated and the suitability of the differentially labeled antibodies for Western blot immunoassays of a complex liver microsomal protein fraction was tested. Limits of detection (LODs) in the lower fmol range were reached in the Western blot application using MeCAT and MAXPAR as element labeling reagents, whereas even sub-fmol LODs can be achieved in a dot blot experiment for the pure antibodies.
PY - 2012
DO - https://doi.org/10.1039/c2ja30068k
SN - 0267-9477
SN - 1364-5544
N1 - Geburtsname von Müller, Larissa: Wäntig, L. - Birth name of Müller, Larissa: Wäntig, L.
N1 - Geburtsname von Hösl, Simone: Hardt, S. - Birth name of Hösl, Simone: Hardt, S.
VL - 27
IS - 8
SP - 1311
EP - 1320
PB - Royal Society of Chemistry
CY - London
AN - OPUS4-26256
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stephan, H.
A1 - Kubeil, M.
A1 - Emmerling, Franziska
A1 - Müller, C.E.
T1 - Polyoxometalates as versatile enzyme inhibitors
N2 - Polyoxometalates (POMs) are inorganic cluster compounds that have been shown to possess a number of pharmacological properties, including antidiabetic, antibacterial, antiprotozoal, antiviral and anticancer activities. Their molecular mechanism of action is largely unknown. However, several studies indicate that many of their activities may be due to the inhibition of enzymes, in particular, of those enzymes that are accessible from the extracellular space and do not require the penetration of cell membranes. In this review, we describe the recent progress in the preparation and optimization of POMs, and an evaluation of their use as inhibitors of different families of enzymes. The next important steps in this area of research will be to gain a better understanding of the interactions of POMs with enzymes on a structural level through an X-ray crystallographic study of enzyme–POM complexes and the analysis of structure–activity relationships. Furthermore, POMs with increased stability and in vivo half-lives have to be prepared. Surface modification may allow the targeting of POM drugs at their sites of action.
KW - Cluster compounds
KW - Polyoxometalates
KW - Metalloprotein mimics
KW - Enzymes
KW - Inhibitors
KW - Bioinorganic chemistry
PY - 2013
DO - https://doi.org/10.1002/ejic.201201224
SN - 1434-1948
SN - 1099-0682
VL - 2013
IS - 10-11
SP - 1585
EP - 1594
PB - Wiley-VCH Verl.
CY - Weinheim
AN - OPUS4-28076
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schwarz, G.
A1 - Müller, Larissa
A1 - Beck, S.
A1 - Linscheid, M.W.
T1 - DOTA based metal labels for protein quantification: a review
N2 - Today, quantitative data play a pivotal role in the understanding of biological processes. This is particularly true for the proteome: protein quantification always follows protein identification. To obtain useful and reliable quantitative data, rather sophisticated strategies using electrospray and MALDI mass spectrometry have been developed, which allow relative and sometimes even absolute quantification. All of those strategies have merits and limitations. In order to overcome some of these limits, methods based on the reliable and sensitive detection and quantification of heavy metals present in proteins using inductively coupled plasma (ICP)-MS have been reported. With specific labels carrying heavy metals, the applicability of ICP-MS has been extended to almost every protein. One of such covalently bound metal tags, allowing the quantification of low abundant proteins, uses 1,4,7,10-tetraazacyclododecane N,N',N'',N''-tetraacetic acid (DOTA) chelate complexes carrying lanthanides as the metal core. In this review the scope and limitations of peptide and protein quantification will be addressed. The metal tags do not only provide low detection limits, but also due to the large number of different lanthanides and lanthanide isotopes, multiplexing capabilities and previously unknown accuracy based on inherently possible isotope dilution methods came into reach. The developed workflows, including electrophoretic and chromatographic separation and preconcentration techniques, will be addressed to allow a comparison with already established procedures.
KW - Protein quantification
KW - ICP-MS
KW - DOTA
KW - Labeling
PY - 2014
DO - https://doi.org/10.1039/c3ja50277e
SN - 0267-9477
SN - 1364-5544
VL - 29
IS - 2
SP - 221
EP - 233
PB - Royal Society of Chemistry
CY - London
AN - OPUS4-30730
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wisniewski, W.
A1 - Thieme, C.
A1 - Müller, Ralf
A1 - Reinsch, Stefan
A1 - Groß-Barsnick, S.-M.
A1 - Rüssel, C.
T1 - Oriented surface nucleation and crystal growth in a 18BaO·22CaO·60SiO2 mol% glass used for SOFC seals
N2 - A glass of the composition 37BaO·16CaO·47SiO2 wt% produced on an industrial scale is crystallized at 970 °C for times ranging from 15 min to 2 h. The crystallization at the immediate surface as well as the crystal growth into the bulk are analyzed using scanning electron microscopy (SEM) including energy dispersive X-ray spectroscopy (EDXS) and electron backscatter diffraction (EBSD) as well as X-ray diffraction in the Θ–2Θ setup (XRD). The immediate surface shows the oriented nucleation of walstromite as well as the formation of wollastonite and an unknown phase of the composition BaCaSi3O8. All three phases also grow into the bulk where walstromite ultimately dominates the kinetic selection and grows throughout the bulk due to a lack of bulk nucleation. Walstromite shows systematic orientation changes as well as twinning during growth. A critical analysis of the XRD-patterns acquired from various crystallized samples indicates that their evaluation is problematic and that phases detected by XRD in this system should be verified by another method such as EDXS.
KW - Glass
KW - Surface nucleation
KW - Orientation
KW - EBSD
PY - 2018
DO - https://doi.org/10.1039/c7ce02008b
VL - 20
IS - 6
SP - 787
EP - 795
PB - Royal Society of Chemistry
AN - OPUS4-44405
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Reinsch, Stefan
A1 - Nascimento, M.L.F.
A1 - Müller, Ralf
A1 - Zanotto, E. D.
T1 - Crystal growth kinetics in cordierite and diopside glasses in wide temperature ranges
N2 - We measured and collected literature data for the crystal growth rate, u(T), of µ-cordierite (2MgO · 2Al2O3 · 5SiO2) and diopside (CaO · MgO · 2SiO2) in their isochemical glass forming melts. The data cover exceptionally wide temperature ranges, i.e. 8001350 °C for cordierite and 7501378 °C for diopside. The maximum of u(T) occurs at about 1250 °C for both systems. A smooth shoulder is observed around 970 °C for µ-cordierite. Based on measured and collected viscosity data, we fitted u(T) using standard crystal growth models. For diopside, the experimental u(T) fits well to the 2D surface nucleation model and also to the screw dislocation growth mechanism. However, the screw dislocation model yields parameters of more significant physical meaning. For cordierite, these two models also describe the experimental growth rates. However, the best fittings of u(T) including the observed shoulder, were attained for a combined mechanism, assuming that the melt/crystal interface growing from screw dislocations is additionally roughened by superimposed 2D surface nucleation at large undercoolings, starting at a temperature around the shoulder. The good fittings indicate that viscosity can be used to assess the transport mechanism that determines crystal growth in these two systems, from the melting point Tm down to about Tg, with no sign of a breakdown of the StokesEinstein/Eyring equation.
KW - Crystal growth
KW - Oxide glasses
KW - Silicates
KW - Kristallwachstumsgeschwindigkeit
KW - Kinetik
KW - Silikatgläser
PY - 2008
DO - https://doi.org/10.1016/j.jnoncrysol.2008.09.007
SN - 0022-3093
VL - 354
IS - 52-54
SP - 5386
EP - 5394
PB - North-Holland Publ. Co.
CY - Amsterdam
AN - OPUS4-18383
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, M.E.H.
A1 - Urban, K.
A1 - Köppen, Robert
A1 - Siegel, David
A1 - Korn, U.
A1 - Koch, Matthias
T1 - Mycotoxins as antagonistic or supporting agents in the interaction between phytopathogenic Fusarium and Alternaria fungi
N2 - The role of mycotoxins in the microbial competition in an ecosystem or on the same host plant is still unclear. Therefore, a laboratory study was conducted to evaluate the influence of mycotoxins on growth and mycotoxin production of Fusarium and Alternaria fungi. Fusarium culmorum Fc13, Fusarium graminearum Fg23 and two Alternaria tenuissima isolates (At18 and At220) were incubated on wheat kernels supplemented with alternariol (AOH), tetramic acid derivates (TeA), deoxynivalenol (DON) and zearalenone (ZEA) in an in vitro test system. Fungal biomass was quantified by determining ergosterol content. Three Fusarium toxins (DON, nivalenol and ZEA) and three Alternaria toxins (AOH, alternariol methyl ether (AME) and altenuene) were analysed by HPLC-MS/MS. If Alternaria strains grew in wheat kernels spiked with Fusarium mycotoxins, their growth rates were moderately increased, their AOH and AME production was enhanced and they were simultaneously capable of degrading the Fusarium mycotoxins DON and ZEA. In contrast, both Fusarium strains behaved quite differently. The growth rate of Fc13 was not distinctly influenced, while Fg23 increased its growth in wheat kernels spiked with AOH. TeA depressed the ergosterol content in Fc13 as well as in Fg23. The DON production of Fc13 was slightly depressed, whereas the ZEA production was significantly increased. In contrast, Fg23 restricted its ZEA production. Both Fusarium strains were not capable of degrading the Alternaria mycotoxin AOH. Mycotoxins might play an important role in the interfungal competitive processes. They influence growth rates and mycotoxin production of the antagonistic combatants. The observed effects between phytopathogenic Alternaria and Fusarium strains and their mycotoxins aid the understanding of the complexity of microbial competitive behaviour in natural environments.
KW - Phytopathogen
KW - Trichothecenes
KW - Alternaria mycotoxins
KW - Multi-mycotoxin analysis
KW - Inter-fungal competition
PY - 2015
DO - https://doi.org/10.3920/WMJ2014.1747
SN - 1875-0710
SN - 1875-0796
VL - 8
IS - 3
SP - 311
EP - 321
PB - Wageningen Academic Publishers
CY - Wageningen
AN - OPUS4-32849
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hoffmann, A.
A1 - Lischeid, G.
A1 - Koch, Matthias
A1 - Lentzsch, P.
A1 - Sommerfeld, Thomas
A1 - Müller, M.H.
T1 - Co-Cultivation of Fusarium, Alternaria, and Pseudomonas on Wheat-Ears Affects Microbial Growth and Mycotoxin Production
N2 - Mycotoxigenic fungal pathogens Fusarium and Alternaria are a leading cause of loss in cereal production. On wheat-ears, they are confronted by bacterial antagonists such as pseudomonads.
Studies on these groups’ interactions often neglect the infection process’s temporal aspects and the associated priority effects. In the present study, the focus was on how the first colonizer affects the subsequent ones. In a climate chamber experiment, wheat-ears were successively inoculated with two different strains (Alternaria enuissima At625, Fusarium graminearum Fg23, or Pseudomonas simiae Ps9).
Over three weeks, microbial abundances and mycotoxin concentrations were analyzed and visualized via Self Organizing Maps with Sammon Mapping (SOM-SM). All three strains revealed different characteristics and strategies to deal with co-inoculation: Fg23, as the first colonizer, suppressed the establishment of At625 and Ps9. Nevertheless, primary inoculation of At625 reduced all of the Fusarium toxins and stopped Ps9 from establishing. Ps9 showed priority effects in delaying and blocking the production of the fungal mycotoxins. The SOM-SM analysis visualized the competitive strengths: Fg23 ranked first, At625 second, Ps9 third. Our findings of species-specific priority effects in a natural environment and the role of the mycotoxins involved are relevant for developing biocontrol strategies.
KW - Antagonists
KW - Microbe interactions
KW - Mycotoxins
KW - Priority effect
KW - SOM-SM
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521554
DO - https://doi.org/10.3390/microorganisms9020443
VL - 9
IS - 2
SP - 443
PB - MDPI
AN - OPUS4-52155
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, M.E.H.
A1 - Steier, I.
A1 - Köppen, Robert
A1 - Proske, Matthias
A1 - Korn, U.
A1 - Koch, Matthias
A1 - Siegel, David
T1 - Cocultivation of phytopathogenic Fusarium and Alternaria strains affects fungal growth and mycotoxin production
N2 - Aims: A laboratory study was conducted to evaluate the influence of cocultivation of toxigenic Fusarium (F.) and Alternaria (A.) fungi with respect to growth and mycotoxin production.
Methods and Results: Fusarium culmorum Fc13, Fusarium graminearum Fg23 and two Alternaria tenuissima isolates (At18 and At220) were simultaneously or consecutively co-incubated on wheat kernels in an in vitro test system. Fungal biomass was quantified by determining ergosterol content. Three Fusarium toxins (DON, NIV and ZON) and three Alternaria toxins (AOH, AME and ALT) were analysed by a newly developed HPLC/MS/MS method. In simultaneous cocultures, the fungal biomass was enhanced up to 460% compared with individual cultures; Alternaria toxins were considerably depressed down to <5%. Combining At18 and At220 with Fg23 inhibited the toxin production of both fungal partners. In contrast, Fc13 increased its DON and ZON production in competitive interaction with both A. strains.
Conclusions: The interfungal competitive effects aid the understanding of the processes of competition of both fungi in natural environments and the involvement of mycotoxins as antifungal factors.
Significance and Impact of Study:
Cocultivation significantly affects fungal growth and mycotoxin production of phytopathogenic Alternaria and Fusarium strains. The impact of mycotoxins on the interfungal competition is highlighted.
KW - Alternaria
KW - Cocultivation
KW - Ergosterol
KW - Fusarium
KW - Interfungal competition
KW - Multimycotoxin analysis
PY - 2012
DO - https://doi.org/10.1111/j.1365-2672.2012.05388.x
SN - 1364-5072
VL - 113
IS - 4
SP - 874
EP - 887
PB - Wiley-Blackwell
CY - Malden, Mass., USA
AN - OPUS4-26932
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -