TY - JOUR A1 - Wang, Y.-W. A1 - Descalzo López, Ana Belén A1 - Shen, Z. A1 - You, X.-Z. A1 - Rurack, Knut T1 - Dihydronaphthalene-fused Boron-dipyrromethene (BODIPY) dyes: insight into the electronic and conformational tuning modes of BODIPY fluorophones KW - Farbstoffe KW - Fluoreszenz KW - NMR-Spektroskopie KW - Synthese PY - 2012 DO - https://doi.org/10.1002/chem.201201081 SN - 0947-6539 SN - 1521-3765 VL - 18 IS - 23 SP - 7306 EP - 7309 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-27113 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, Y.-W. A1 - Descalzo López, Ana Belén A1 - Shen, Z. A1 - You, X.-Z. A1 - Rurack, Knut T1 - Dihydronaphthalene-fused Boron-dipyrromethene (BODIPY) dyes: insight into the electronic and conformational tuning modes of BODIPY fluorophores N2 - A new series of boron-dipyrromethene (BDP, BODIPY) dyes with dihydronaphthalene units fused to the β-pyrrole positions (1 a-d, 2) has been synthesised and spectroscopically investigated. All the dyes, except pH-responsive 1 d in polar solvents, display intense emission between 550-700 nm. Compounds 1 a and 1 b with a hydrogen atom and a methyl group in the meso position of the BODIPY core show spectroscopic properties that are similar to those of rhodamine 101, thus rendering them potent alternatives to the positively charged rhodamine dyes as stains and labels for less polar environments or for the dyeing of latex beads. Compound 1 d, which carries an electron-donating 4-(dimethylamino)phenyl group in the meso position, shows dual fluorescence in solvents more polar than dibutyl ether and can act as a pH-responsive "light-up" probe for acidic pH. Correlation of the pKa data of 1 d and several other meso-(4-dimethylanilino)-substituted BODIPY derivatives allowed us to draw conclusions on the influence of steric crowding at the meso position on the acidity of the aniline nitrogen atom. Preparation and investigation of 2, which carries a nitrogen instead of a carbon as the meso-bridgehead atom, suggests that the rules of colour tuning of BODIPYs as established so far have to be reassessed; for all the reported couples of meso-C- and meso-N-substituted BODIPYs, the exchange leads to pronounced redshifts of the spectra and reduced fluorescence quantum yields. For 2, when compared with 1 a, the opposite is found: negligible spectral shifts and enhanced fluorescence. Additional X-ray crystallographic analysis of 1 a and quantum chemical modelling of the title and related compounds employing density functional theory granted further insight into the features of such sterically crowded chromophores. KW - Dyes/pigments KW - Fluorescent probes KW - Photophysics KW - Protonation KW - Boron PY - 2010 DO - https://doi.org/10.1002/chem.200902527 SN - 0947-6539 SN - 1521-3765 VL - 16 IS - 9 SP - 2887 EP - 2903 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-20957 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rienitz, O. A1 - Pramann, A. A1 - Vogl, Jochen A1 - Lee, K.-S. A1 - Yim, Y.-H. A1 - Malinovskiy, D. A1 - Hill, S. A1 - Dunn, P. A1 - Goenaga-Infante, H. A1 - Ren, T. A1 - Wang, J. A1 - Vocke jr., R. D. A1 - Rabb, S: A. A1 - Narukawa, T. A1 - Yang, L. A1 - Mester, Z. A1 - Meija, J. A1 - Aref'ev, D. G. A1 - Marchin, V. A1 - Sharin, A. G. A1 - Bulanov, A. D. A1 - Potapov, A. M. A1 - Otopkova, P. A. A1 - Kessel, R. T1 - The comparability of the determination of the molar mass of silicon highly enriched in 28Si: results of the CCQM-P160 interlaboratory comparison and additional external measurements N2 - An international comparison study on the accurate determination of the molar mass M(Si) of silicon artificially enriched in 28Si (x(28Si) > 0.9999 mol mol−1) has been completed. The measurements were part of the high level CCQM-P160 pilot study assessing the ability of National Metrology Institutes (NMIs) and Designated Institutes (DIs) to make such measurements at the lowest possible levels of measurement uncertainty and to identify possible difficulties when measuring this kind of sample. This study supports the molar mass measurements critical to disseminating the silicon route to realizing the new definitions for the kilogram and the mole. Measurements were also made by one external research institute and an external company. The different institutes were free to choose their experimental (mass spectrometric) set-ups and equipment, thereby enabling also the comparison of different techniques. The investigated material was a chemically pure, polycrystalline silicon material. The subsequent modified single crystalline secondary product of this material was intended for the production of silicon which was used for two additional spheres in the context of the redetermination of the Avogadro constant NA, required for the revision of the International System of Units (SI) via fundamental constants which came into force from May 2019. The CCQM pilot study was organized by Physikalisch-Technische Bundesanstalt (PTB). Aqueous silicon solutions were shipped to all participating institutions. The data analysis as well as the uncertainty modelling and calculation of the results was predefined. The participants were provided with an uncertainty budget as a GUM Workbench® file as well as a free software license for the duration of the comparison. The agreement of the values of the molar mass (M(Si) = 27.976 942 577 g mol−1) was excellent with ten out of 11 results reported within the range of relative uncertainty of 1 × 10−8 required for the revision of the SI. KW - Absolute isotope ratio KW - Molar mass KW - Avogadro constant KW - Revision of the SI PY - 2020 DO - https://doi.org/10.1088/1681-7575/abbdbf VL - 57 IS - 6 SP - 065028 PB - IOP Science CY - Cambridge AN - OPUS4-51500 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, D. A1 - Ji, T. A1 - Jing, Q. A1 - He, W. A1 - Fan, Z. A1 - Wu, Dejian A1 - Qian, X. T1 - Experimental study and mechanism model on the ignition sensitivity of typical organic dust clouds in O2/N2, O2/Ar and O2/CO2 atmospheres N2 - To reveal and improve our understanding of the ignition behavior and mechanism, G-G furnace experiments of three typical organic dusts were performed to investigate the minimum ignition temperature (MIT) in O2/N2, O2/ Ar and O2/CO2 atmospheres with oxygen mole fraction from 8.4% to 50%. The experimental results were presented in oxygen-lean and oxy-fuel atmospheres to evaluate the ignition sensitivity of dusts in different atmospheres. It was found that CO2 is the strongest in terms of lowing the ignition sensitivity of the three dusts, and the dust explosion risk increases significantly with increasing O2 mole fraction for the three dusts through a logarithmically and significantly reducing MIT. However, for different dusts, inert gases show different suppression effects. In addition, a modified steady-state homogeneous ignition model was proposed and successfully applied to oxygen-lean atmospheres, and in oxy-fuel atmospheres, this model has also been improved to estimate the ignition mechanism. This ignition mechanism model could be used to successfully predict the minimum ignition temperature of high volatile dust under different inert atmospheres controlled by homogeneous ignition, which will provide a reference for the ignition hazard assessment of dust on hot surfaces. KW - Dust explosions KW - Gas explosions KW - Minimum ignition temperature KW - Hybrid mixtures PY - 2021 DO - https://doi.org/10.1016/j.jhazmat.2021.125108 SN - 0304-3894 VL - 412 SP - 125108 PB - Elsevier B.V. AN - OPUS4-53660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - He, Shulin A1 - Sieksmeyer, Thorben A1 - Che, Y. A1 - Mora, M. A. E. A1 - Stiblik, P. A1 - Banasiak, Ronald A1 - Harrison, M. C. A1 - Sobotnik, J. A1 - Wang, Z. A1 - Johnston, P. R. A1 - McMahon, Dino Peter T1 - Evidence for reduced immune gene diversity and activity during the evolution of termites N2 - The evolution of biological complexity is associated with the emergence of bespoke immune systems that maintain and protect organism integrity. Unlike the well-studied immune systems of cells and individuals, little is known about the origins of immunity during the transition to eusociality, a major evolutionary transition comparable to the evolution of multicellular organisms from single-celled ancestors. We aimed to tackle this by characterizing the immune gene repertoire of 18 cockroach and termite species, spanning the spectrum of solitary, subsocial and eusocial lifestyles. We find that key transitions in termite sociality are correlated with immune gene family contractions. In cross-species comparisons of immune gene expression, we find evidence for a caste-specific social defence system in termites, which appears to operate at the expense of individual immune protection. Our study indicates that a major transition in organismal complexity may have entailed a fundamental reshaping of the immune system optimized for group over individual defence. KW - Social insect KW - Subsocial KW - Cockroach KW - Major transition KW - Contraction KW - Expansion PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538878 DO - https://doi.org/10.1098/rspb.2020.3168 SN - 0962-8452 SN - 1471-2954 VL - 288 IS - 1945 SP - 1 EP - 10 PB - The Royal Society CY - London AN - OPUS4-53887 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Szymoniak, Paulina A1 - Qu, Xintong A1 - Abbasi, M. A1 - Pauw, Brian Richard A1 - Henning, S. A1 - Li, Z. A1 - Wang, D.-Y. A1 - Schick, C. A1 - Saalwächter, K. A1 - Schönhals, Andreas T1 - Spatial inhomogeneity, Interfaces and Complex Vitrification Kinetics in a Network Forming Nanocomposite N2 - A detailed calorimetric study on an epoxy-based nanocomposite system was performed employing bisphenol A diglycidyl ether (DGEBA) cured with diethylenetriamine (DETA) as the polymer matrix and taurine-modified MgAL layered double hydroxide (T-LDH) as nanofiller. The -NH2 group of taurine can react with DGEBA improving the interaction of the polymer with the filler. The combined X-ray scattering, and electron microscopy data showed that the nanocomposite has a partially exfoliated morphology. Calorimetric studies were performed with conventional DSC, temperature modulated DSC (TMDSC) and fast scanning calorimetry (FSC) in the temperature modulated approach (TMFSC) to investigate the vitrification and molecular mobility in dependence of the filler concentration. First, TMDSC and NMR were used to estimate the amount of the rigid amorphous fraction which consists of immobilized polymer segments at the nanoparticle surface. It was found to be 40 wt% for the highest filler concentration, indicating that the interface dominates the overall macroscopic properties and behavior of the material to a great extent. Second, the relaxation rates of the α-relaxation obtained by TMDSC and TMFSC were compared with the thermal and dielectric relaxation rates measured by static FSC. The investigation revealed that the system shows two distinct α-relaxation processes. Furthermore, also two separate vitrification mechanisms were found for a bulk network-former without geometrical confinement as also confirmed by NMR. This was discussed in terms of the intrinsic spatial heterogeneity on a molecular scale, which becomes more pronounced with increasing nanofiller content. KW - Polymer based Nanocomposites PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-523199 DO - https://doi.org/10.1039/d0sm01992e SN - 1744-6848 VL - 17 IS - 10 SP - 2775 EP - 2790 PB - Royal Society of Chemistry AN - OPUS4-52319 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jiang, Shixiong A1 - Marco, H. G. A1 - Scheich, Nina A1 - He, S. A1 - Wang, Z. A1 - Gäde, G. A1 - McMahon, Dino Peter T1 - Comparative analysis of adipokinetic hormones and their receptors in Blattodea reveals novel patterns of gene evolution N2 - Adipokinetic hormone (AKH) is a neuropeptide produced in the insect corpora cardiaca that plays an essential role in mobilising carbohydrates and lipids from the fat body to the haemolymph. AKH acts by binding to a rhodopsin-like G protein-coupled receptor (GPCR), the adipokinetic hormone receptor (AKHR). In this study, we tackle AKH ligand and receptor gene evolution as well as the evolutionary origins of AKH gene paralogues from the order Blattodea (termites and cockroaches). Phylogenetic analyses of AKH precursor sequences point to an ancient AKH gene duplication event in the common ancestor of Blaberoidea, yielding a new group of putative decapeptides. In total, 16 different AKH peptides from 90 species were obtained. Two octapeptides and seven putatively novel decapeptides are predicted for the first time. AKH receptor sequences from 18 species, spanning solitary cockroaches and subsocial wood roaches as well as lower and higher termites, were subsequently acquired using classical molecular methods and in silico approaches employing transcriptomic data. Aligned AKHR open reading frames revealed 7 highly conserved transmembrane regions, a typical arrangement for GPCRs. Phylogenetic analyses based on AKHR sequences support accepted relationships among termite, subsocial (Cryptocercus spp.) and solitary cockroach lineages to a large extent, while putative post-translational modification sites do not greatly differ between solitary and subsocial roaches and social termites. Our study provides important information not only for AKH and AKHR functional research but also for further analyses interested in their development as potential candidates for biorational pest control agents against invasive termites and cockroaches. KW - Adipokinetic hormone KW - Adipokinetic hormone receptor KW - ‘Green’ pesticide KW - Neuropeptide KW - Termite PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579141 DO - https://doi.org/10.1111/imb.12861 SN - 0962-1075 SP - 1 EP - 19 PB - Wiley online library CY - London, UK AN - OPUS4-57914 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yang, L. A1 - Vogl, Jochen A1 - Mann, J. A1 - Kraft, R. A1 - Vocke, R. A1 - Pramann, A. A1 - Eberhardt, J. A1 - Rienitz, O. A1 - Lee, K.-S. A1 - Lim, J. S. A1 - Sobina, E. A1 - Song, P. A1 - Wang, J. A1 - Mester, Z. A1 - Meija, J. T1 - Copper isotope delta measurements in high purity materials: CCQM-P213 pilot study N2 - Accurate and precise isotope ratio measurements of heavy elements are playing an increasinglyimportant role in modern analytical sciences and have numerous applications. Today, isotope ratio measurements are typically performed with two principal techniques: thermal ionization mass spectrometry (TIMS) and multiple collector-inductively coupled plasma mass spectrometry (MC-ICP-MS). To obtain accurate results by mass spectrometry, isotopic certified reference materials (iCRMs) are needed for mass bias correction and for the validation of the method used for analysis.Thus, it is of paramount importance to achieve measurement comparability of all data reported, and to assess measurement capability of each CRM producer/National Metrology Institute (NMI). Therefore, the international comparison (CCQM-P213) was performed to assess the analytical capabilities of NMIs for the accurate determination of copper isotope ratio delta values in high purity materials. The study was proposed by the coordinating laboratories, National Research Council Canada (NRC), National Institute of Standards and Technology (NIST), Bundesanstalt für Materialforschung und -prüfung (BAM) and Physikalisch-Technische Bundesanstalt (PTB), as an activity of the Isotope Ratio Working Group (IRWG) of the Consultative Committee for Amount of Substance - Metrology in Chemistry and Biology (CCQM). Participants included six NMIs and one designated institute (DI) from the six countries. Although no measurement method was prescribed by the coordinating laboratories, MC-ICP-MS with either standard-sample bracketing (SSB) or combined SSB with internal normalization (C-SSBIN) models for mass bias correction were recommended. Results obtained from the six NMIs and one DI were in good agreement. KW - Comparability KW - Traceability KW - Metrology KW - Isotope delta KW - Copper PY - 2023 DO - https://doi.org/10.1088/0026-1394/60/1A/08019 VL - 60 IS - 1A SP - 1 EP - 23 PB - IOP Science AN - OPUS4-58040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Was, G.S. A1 - Bahn, C.-B. A1 - Busby, J. A1 - Cui, B. A1 - Farkas, D. A1 - Gussev, M. A1 - Rigen He, M. A1 - Hesterberg, J. A1 - Jiao, Z. A1 - Johnson, D. A1 - Kuang, W. A1 - McMurtrey, M. A1 - Robertson, I. A1 - Sinjlawi, A. A1 - Song, M. A1 - Stephenson, K. A1 - Sun, K. A1 - Swaminathan, Srinivasan A1 - Wang, M. A1 - West, E. T1 - How irradiation promotes intergranular stress corrosion crack initiation N2 - Irradiation assisted stress corrosion cracking (IASCC) is a form of intergranular stress corrosion cracking that occurs in irradiated austenitic alloys. It requires an irradiated microstructure along with high temperature water and stress. The process is ubiquitous in that it occurs in a wide range of austenitic alloys and water chemistries, but only when the alloy is irradiated. Despite evidence of this degradation mode that dates back to the 1960s, the mechanism by which it occurs has remained elusive. Here, using high resolution electron backscattering detection to analyze local stress-strain states, high resolution transmission electron microscopy to identify grain boundary phases at crack tips, and decoupling the roles of stress and grain boundary oxidation, we are able to unfold the complexities of the phenomenon to reveal the mechanism by which IASCC occurs. The significance of the findings impacts the mechanical integrity of core components of both current and advanced nuclear reactor designs worldwide. KW - Irradiation KW - Stress corrosion cracking KW - Grain boundaries KW - Oxidation KW - Austenitic alloys PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595748 DO - https://doi.org/10.1016/j.pmatsci.2024.101255 SN - 0079-6425 VL - 143 SP - 1 EP - 15 PB - Elsevier AN - OPUS4-59574 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ressel, P. A1 - Hao, P.H. A1 - Park, M.H. A1 - Yang, Z. C. A1 - Wang, L.C. A1 - Österle, Werner A1 - Kurpas, P. A1 - Richter, E. A1 - Kuphal, E. A1 - Hartnagel, H.L. T1 - Pd/Sb(Zn) and Pd/Ge(Zn) Ohmic Contacts on p-Type Indium Gallium Arsenide: The Employment of the Solid Phase Regrowth Principle to Achieve Optimum Electrical and Metallurgical Properties N2 - The development of two metallizations based on the solid-phase regrowth principle is presented, namely Pd/Sb(Zn) and Pd/Ge(Zn) on moderately doped In0.53Ga0.47As (p=4×1018 cm-3). Contact resistivities of 2–3×10-7 and 6–7×10-7 ?cm2, respectively, have been achieved, where both systems exhibit an effective contact reaction depth of zero and a Zn diffusion depth below 50 nm. Exhibiting resistivities equivalent to the lowest values of Au-based systems in this doping range, especially Pd/Sb(Zn) contacts are superior to them concerning metallurgical stability and contact penetration. Both metallizations have been successfully applied for contacting the base layer of InP/In0.53Ga0.47As heterojunction bipolar transistors. KW - Ohmic contacts KW - Indium gallium arsenide KW - InP/InGaAs heterojunction bipolar transistor KW - Solid-phase regrowth KW - Pd/Ge contacts KW - Pd/Sb contacts KW - Backside secondary ion mass spectrometry (SIMS) PY - 2000 DO - https://doi.org/10.1007/s11664-000-0189-y SN - 0361-5235 SN - 1543-186X VL - 29 IS - 7 SP - 964 EP - 972 PB - TMS CY - Warrendale, Pa. AN - OPUS4-7642 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, Z. A1 - Villa Santos, C. A1 - Legrand, A. A1 - Haase, F. A1 - Hara, Y. A1 - Kanamori, K. A1 - Aoyama, T. A1 - Urayama, K. A1 - Doherty, C. M. A1 - Smales, Glen Jacob A1 - Pauw, Brian Richard A1 - Colon, Y. J. A1 - Furukawa, S. T1 - Multiscale structural control of linked metal–organic polyhedra gel by aging-induced linkage-reorganization N2 - Assembly of permanently porous metal–organic polyhedra/cages (MOPs) with bifunctional linkers leads to soft supramolecular networks featuring both porosity and processability. However, the amorphous nature of such soft materials complicates their characterization and thus limits rational structural control. Here we demonstrate that aging is an effective strategy to control the hierarchical network of supramolecular gels, which are assembled from organic ligands as linkers and MOPs as junctions. Normally, the initial gel formation by rapid gelation leads to a kinetically trapped structure with low controllability. Through a controlled post-synthetic aging process, we show that it is possible to tune the network of the linked MOP gel over multiple length scales. This process allows control on the molecular-scale rearrangement of interlinking MOPs, mesoscale fusion of colloidal particles and macroscale densification of the whole colloidal network. In this work we elucidate the relationships between the gel properties, such as porosity and rheology, and their hierarchical structures, which suggest that porosity measurement of the dried gels can be used as a powerful tool to characterize the microscale structural transition of their corresponding gels. This aging strategy can be applied in other supramolecular polymer systems particularly containing kinetically controlled structures and shows an opportunity to engineer the structure and the permanent porosity of amorphous materials for further applications. KW - SAXS KW - Metal-organic polyhedra KW - Structural control PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532309 DO - https://doi.org/10.1039/d1sc02883a SN - 1478-6524 SN - 1742-2183 VL - 12 IS - 38 SP - NIL_1 EP - NIL_9 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-53230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Omar, Hassan A1 - Smales, Glen Jacob A1 - Henning, S. A1 - Li, Z. A1 - Wang, D.-Y. A1 - Schönhals, Andreas A1 - Szymoniak, Paulina T1 - Calorimetric and Dielectric Investigations of Epoxy-Based Nanocomposites with Halloysite Nanotubes as Nanofillers N2 - Epoxy nanocomposites are promising materials for industrial applications (i.e., aerospace, marine and automotive industry) due to their extraordinary mechanical and thermal properties. Here, the effect of hollow halloysite nanotubes (HNT) on an epoxy matrix (Ep) was the focus of the study. The structure and molecular mobility of the nanocomposites were investigated using a combination of X-ray scattering, calorimetry (differential (DSC) and fast scanning calorimetry (FSC)) and dielectric spectroscopy. Additionally, the effect of surface modification of HNT (polydopamine (PDA) and Fe(OH)3 nanodots) was considered. For Ep/HNT, the glass transition temperature (Tg) is was de-creased due to a nanoparticle-related decrease of the crosslinking density. For the modified system, Ep/m-HNT, the surface modification resulted in enhanced filler–matrix interactions leading to higher Tg values than the pure epoxy in some cases. For Ep/m-HNT, the amount of interface formed between the nanoparticles and the matrix ranged from 5% to 15%. Through BDS measurements, localized fluctuations were detected as a β- and γ-relaxation, related to rotational fluctuations of phenyl rings and local reorientations of unreacted components. A combination of calorimetry and BDS dielectric spectroscopy revealed a dynamic and structural heterogeneity of the matrix, as confirmed by two glassy dynamics in both systems, related to regions with different crosslinking densities. KW - Rigid amorphous fraction KW - Epoxy nanocomposites KW - Halloysite nanotubes KW - X-ray scattering KW - Differential scanning calorimetry KW - Broadband dielectric spectroscopy KW - Flash DSC PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-526668 DO - https://doi.org/10.3390/polym13101634 VL - 13 IS - 10 SP - 1634 PB - MDPI AN - OPUS4-52666 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhou, Z. A1 - Han, Q. A1 - Wang, D. A1 - Macé, T. A1 - Kipphardt, Heinrich A1 - Maiwald, Michael A1 - Tuma, Dirk A1 - Uehara, S. A1 - Akima, D. A1 - Shimosaka, T. A1 - Jung, J. A1 - Oh, S.-H. A1 - van der Veen, A. A1 - van Wijk, J.I.T. A1 - Ziel, P. R. A1 - Konopelko, L. A1 - Valkova, M. A1 - Mogale, D.M. A1 - Botha, A. A1 - Brewer, P. A1 - Murugan, A. A1 - Minnaro, M.D. A1 - Miller, M. A1 - Guenther, F. A1 - Kelly, M.E. T1 - CCQM K101 Final report international comparison CCQM-K101:Oxygen in nitrogen-a track B comparison and that the matrix contains argon N2 - This key comparison aims to assess the capabilities of the participants to determine the amount-of-substance fraction oxygen in nitrogen. The GAWG has classified this as a track B comparison, due to the unexpected 50 μmol/mol argon mole fraction content of the transfer standards, which effects the achievable performance of some measurement techniques such a GC-TCD. The separation of oxygen and argon is challenging, and not all systems in use are equally well designed for it. As this analytical challenge due to a substantial fraction of argon in the transfer standards became a reality, the Gas Analysis Working Group (GAWG) decided to qualify this key comparison as a regular key comparison and not as a core comparison, which may be used to support calibration and measurement capabilities (CMCs) for oxygen in nitrogen, or for oxygen in nitrogen mixtures containing argon only (see also the section on support to CMCs). KW - CCQM-K101 KW - Gas analysis PY - 2016 UR - http://iopscience.iop.org/article/10.1088/0026-1394/53/1A/08013 SN - 1681-7575 SN - 0026-1394 VL - 53 IS - Techn Suppl SP - 08013, 1 EP - 71 PB - IOP publishing AN - OPUS4-40013 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Beyer, S. A1 - Kimani, Martha Wamaitha A1 - Zhang, Y. A1 - Verhassel, A. A1 - Sternbæk, L. A1 - Wang, T. A1 - Persson, J. L. A1 - Härkönen, P. A1 - Johansson, E. A1 - Caraballo, R. A1 - Elofsson, M. A1 - Gawlitza, Kornelia A1 - Rurack, Knut A1 - Ohlsson, L. A1 - El-Schich, Z. A1 - Gjörloff Wingren, A. A1 - Stollenwerk, M. M. T1 - Fluorescent Molecularly Imprinted Polymer Layers against Sialic Acid on Silica-coated Polystyrene Cores - Assessment of the Binding Behavior to Cancer Cells N2 - Sialic acid (SA) is a monosaccharide usually linked to the terminus of glycan chains on the cell surface. It plays a crucial role in many biological processes, and hypersialylation is a common feature in cancer. Lectins are widely used to analyze the cell surface expression of SA. However, these protein molecules are usually expensive and easily denatured, which calls for the development of alternative glycan-specific receptors and cell imaging technologies. In this study, SA-imprinted fluorescent core-shell molecularly imprinted polymer particles (SA-MIPs) were employed to recognize SA on the cell surface of cancer cell lines. The SA-MIPs improved suspensibility and scattering properties compared with previously used core-shell SA-MIPs. Although SA-imprinting was performed using SA without preference for the alpha-2,3- and alpha-2,6-SA forms, we screened the cancer cell lines analyzed using the lectins Maackia Amurensis Lectin I (MAL I, alpha-2,3-SA) and Sambucus Nigra Lectin (SNA, alpha-2,6-SA). Our results show that the selected cancer cell lines in this study presented a varied binding behavior with the SA-MIPs. The binding pattern of the lectins was also demonstrated. Moreover, two different pentavalent SA conjugates were used to inhibit the binding of the SA-MIPs to breast, skin, and lung cancer cell lines, demonstrating the specificity of the SA-MIPs in both flow cytometry and confocal fluorescence microscopy. We concluded that the synthesized SA-MIPs might be a powerful future tool in the diagnostic analysis of various cancer cells. KW - Cancer KW - Imprinting KW - Molecularly imprinted polymers KW - SA conjugates KW - Sialic acid PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546625 DO - https://doi.org/110.3390/cancers14081875 SN - 2072-6694 VL - 14 IS - 8 PB - MDPI CY - Basel AN - OPUS4-54662 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pu, Y. A1 - Lawrence, M. J. A1 - Celorrio, V. A1 - Wang, Q. A1 - Gu, M. A1 - Sun, Z. A1 - Agudo Jácome, Leonardo A1 - Russell, A. E. A1 - Huang, L. A1 - Rodriguez, P. T1 - Nickel confined in 2D earth-abundant oxide layers for highly efficient and durable oxygen evolution catalysts N2 - Low cost, high-efficiency catalysts towards water splitting are urgently required to fulfil the increasing demand for energy. In this work, low-loading (<20 wt%) Ni-confined in layered metal oxide anode catalysts (birnessite and lepidocrocite titanate) have been synthesized by facile ion exchange methodology and subjected to systematic electrochemical studies. It was found that Ni-intercalated on K-rich birnessite (Ni-KMO) presents an onset overpotential (ηonset) as low as 100 mV and overpotential at 10 mA cm−2 (η10) of 206 mV in pH = 14 electrolyte. By combining electrochemical methods and X-ray absorption and emission spectroscopies (XAS and XES), we demonstrate Ni sites are the active sites for OER catalysis and that the Mn3+ sites facilitate Ni intercalation during the ion-exchange process, but display no observable contribution towards OER activity. The effect of the pH and the nature of the supporting electrolyte on the electrochemical performance was also evaluated. KW - Confined catalyst KW - Low-loading KW - Layered manganese oxide KW - Oxygen evolution reaction KW - Transmission electron microscopy (TEM) PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-515027 DO - https://doi.org/10.1039/D0TA04031B SN - 2050-7496 SN - 2050-7488 VL - 8 IS - 26 SP - 13340 EP - 13350 PB - Royal Society of Chemistry CY - London AN - OPUS4-51502 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, Z. A1 - Wegner, Karl David A1 - Stiegler, L. M. S. A1 - Zhou, X. A1 - Rezvani, A. A1 - Odungat, A. S. A1 - Zubiri, B. A. A1 - Wu, M. A1 - Spiecker, E. A1 - Walter, J. A1 - Resch-Genger, Ute A1 - Segets, D. T1 - Optimizing the Shelling Process of InP/ZnS Quantum Dots Using a Single-Source Shell Precursor: Implications for Lighting and Display Applications N2 - InP/ZnS core/shell quantum dots (QDs), recognized as highly promising heavy-metal-free emitters, are increasingly being utilized in lighting and display applications. Their synthesis in a tubular flow reactor enables production in a highly efficient, scalable, and reproducible manner, particularly when combined with a single-source shell precursor, such as zinc diethyldithiocarbamate (Zn(S2CNEt2)2). However, the photoluminescence quantum yield (PLQY) of QDs synthesized with this route remains significantly lower compared with those synthesized in batch reactors involving multiple steps for the shell growth. Our study identifies the formation of absorbing, yet nonemissive ZnS nanoparticles during the ZnS shell formation process as a main contributing factor to this discrepancy. By varying the shelling conditions, especially the shelling reaction temperature and InP core concentration, we investigated the formation of pure ZnS nanoparticles and their impact on the optical properties, particularly PLQY, of the resultant InP/ZnS QDs through ultraviolet−visible (UV−vis) absorption, steady-state and time-resolved photoluminescence (PL) spectroscopy, scanning transmission electron microscopy (STEM), and analytical ultracentrifugation (AUC) measurements. Our results suggest that process conditions, such as lower shelling temperatures or reduced InP core concentrations (resulting in a lower external surface area), encourage homogeneous nucleation of ZnS. This reduces the availability of shell precursors necessary for effective passivation of the InP core surfaces, ultimately resulting in lower PLQYs. These findings explain the origin of persistently underperforming PLQY of InP/ZnS QDs synthesized from this synthesis route and suggest further optimization strategies to improve their emission for lighting and display applications. KW - Nano KW - Particle KW - Synthesis KW - InP KW - Shell KW - Fluorescence KW - Quantum yield KW - ZnS KW - Semiconductor KW - Quantum dot KW - Flow reactor KW - Method KW - AUC KW - Size KW - Automation KW - Sensor PY - 2024 DO - https://doi.org/10.1021/acsanm.4c05265 SN - 2574-0970 VL - 7 IS - 20 SP - 24262 EP - 24273 PB - ACS Publications AN - OPUS4-61518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meng, M. A1 - Zhang, T. A1 - Wang, J. A1 - Cheng, Z. A1 - Liu, Y. A1 - Qiao, X. A1 - Wen, J. A1 - Resch-Genger, Ute A1 - Long, W. A1 - Ou, J. T1 - NaYF4:Yb3+/Tm3+@NaYF4:Yb3+ Upconversion Nanoparticles for Optical Temperature Monitoring and Self-Heating in Photothermal Therapy N2 - The core−shell NaYF4:Yb3+/Tm3+@NaYF4:Yb3+ upconversion nanoparticles were successfully prepared by a solvothermal method, and a layer of mesoporous silica (mSiO2) was successfully coated on the periphery of the core−shell nanoparticles to transform their surface from lipophilic to hydrophilic, further expanding their applications in biological tissues. The physical phase, morphology, structure, and fluorescence properties were characterized by X-ray diffraction (XRD), field emission transmission electron microscopy (TEM), Fourier infrared spectroscopy (FT-IR), ζ potential analysis, and fluorescence spectroscopy. It was found that the material has a hexagonal structure with good hydrophilicity and emits intense fluorescence under 980 nm pump laser excitation. The non-contact temperature sensing performance of nanoparticles was evaluated by analyzing the upconversion fluorescence of Tm3+ (1G4 → 3F4 and 3F3 → 3H6) in the temperature range of 284−344 K. The absolute and relative sensitivities were found to be 0.0067 K−1 and 1.08 % K−1, respectively, with high-temperature measurement reliability and good temperature cycling performance. More importantly, its temperature measurement in phosphate-buffered saline (PBS) solution is accurate. In addition, the temperature of the cells can be increased by adjusting the laser power density and laser irradiation time. Therefore, an optical temperature sensing platform was built to realize the application of real-time monitoring of cancer cell temperature and the dual function of photothermal therapy. KW - Sensor KW - Temperature KW - Lanthanide KW - Tag KW - Fluorescence KW - Nanoparticles KW - Synthesis KW - Environment KW - Monitoring KW - Sensing KW - Nano KW - Life sciences KW - Upconversion PY - 2023 DO - https://doi.org/10.1021/acsanm.2c05110 VL - 6 IS - 1 SP - 759 EP - 771 PB - ACS Publications AN - OPUS4-57081 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meng, M. A1 - Zhang, T. A1 - Wang, J. A1 - Cheng, Z. A1 - Yang, J. A1 - Qiao, X. A1 - Wen, J. A1 - Resch-Genger, Ute A1 - Ou, J. T1 - Fluorescence temperature sensing of NaYF4:Yb3+/Tm3+@NaGdF4:Nd3+/Yb3+ nanoparticles at low and high temperatures N2 - NaYF4:Yb3+/Tm3+@NaGdF4:Nd3+/Yb3+ upconversion nanoparticles (UCNPs) were prepared using a solvothermal method, and the effects of key factors such as the content of sensitiser Nd 3+ and Yb3+ on their luminescence properties were investigated. The nanoparticles are homogeneous in size and well dispersed. Under 808 nm excitation, it can produce strong upconversion fluorescence. At the same time, the nanoparticles have good temperature-sensing properties at the thermally coupled energy levels of 700 nm and 646 nm for Tm3+. Using its fluorescence intensity ratio (FIR), accurate temperature measurements can be performed, and it has been found that it exhibits different temperature sensing properties in low and high-temperature regions. The maximum relative sensitivity was found to be 0.88% K-1 and 1.89% K-1 for the lowtemperature region of 285 K-345 K and the high-temperature region of 345 K-495 K. The nanoparticles were applied to the internal temperature measurement of lithium batteries and the actual high-temperature environment, respectively, and were found to have good temperature measurementt performance. KW - Fluorescence KW - Sensor KW - Temperature KW - Ratiometric KW - Lanthanide KW - Quantum yield KW - Integrating sphere spectroscopy KW - Absolute fluorescence KW - Quality assurance KW - Nano KW - Particle KW - Application KW - Upconversion nanoparticle PY - 2022 DO - https://doi.org/10.1088/1361-6528/ac84e4 SN - 1361-6528 VL - 33 IS - 34 SP - 1 EP - 15 PB - IOP Publishing CY - Bristol AN - OPUS4-55454 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rezvani, A. A1 - Wang, Z. A1 - Wegner, Karl David A1 - Soltanmoradi, H. A1 - Kichigin, A. A1 - Zhou, X. A1 - Gantenberg, T. A1 - Schram, J. A1 - Zubiri, B. A. A1 - Spiecker, E. A1 - Walter, J. A1 - Resch-Genger, Ute A1 - Segets, D. T1 - Separation of Indium Phosphide/Zinc Sulfide Core−Shell Quantum Dots from Shelling Byproducts through Multistep Agglomeration N2 - Semiconductor quantum dots (QDs) possess unique electronic and optical properties, making them promising candidates for applications in lightemitting diodes, solar cells, bioimaging, and photocatalysis. Precise control over their size, shape, and chemical and electronic structure is crucial to ensure the desired functional properties and optimize device performance. However, challenges in QD synthesis and post-synthesis modification persist, especially in large-scale production. This study addresses the classification of QDs synthesized in a tubular flow reactor consisting of a mixture of the desired InP/ZnS core−shell QDs and QDs made from the shell material, i.e., here ZnS QDs formed as a byproduct during the formation step of the ZnS shell. The homogeneous nucleation of ZnS nanoparticles from the shelling material introduces a heterogeneity in size and composition and affects the optical properties of the resulting QDs. To address this issue, we developed a size-selective agglomeration (SSA) technique by incrementally introducing ethanol as a poor solvent and classified the synthesized QDs into 13 distinct fractions. These 13 fractions are sorted into three distinct groups: (i) larger InP/ZnS QDs, (ii) a combination of smaller InP/ZnS QDs and larger ZnS QDs, and (iii) predominant ZnS QDs with some very tiny InP/ZnS QDs. The comprehensive characterization of the fractions was conducted using UV−visible absorption spectroscopy, photoluminescence spectroscopy, high-resolution scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy, total reflection X-ray fluorescence, and analytical ultracentrifugation. We could demonstrate that our method effectively separated unwanted ZnS QDs from the target InP/ZnS QDs. In addition, the fractions enriched in smaller InP/ZnS QDs exhibited a higher photoluminescence quantum yield compared to the fractions with larger QDs. This demonstrates the efficacy of SSA in finetuning the composition of QD mixtures produced on a larger scale to improve their functional properties. This approach provides fundamental understanding toward the development of a scalable two-dimensional classification process for such ultrasmall nanoparticles by particle size and composition. KW - Quality assurance KW - Reference material KW - Nano KW - Particle KW - Quantum dot KW - Synthesis KW - Flow reactor KW - InP KW - Shell KW - ZnS KW - Surface chemistry KW - Method KW - Fluorescence KW - Quantum yield KW - TEM PY - 2025 DO - https://doi.org/10.1021/acsnano.4c18530 SN - 1936-086X VL - 19 IS - 20 SP - 19080 EP - 19094 PB - ACS Publications AN - OPUS4-63215 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sun, C. A1 - Tian, X. A1 - Wang, L. A1 - Liu, Y. A1 - Wirth, Cynthia A1 - Günster, Jens A1 - Li, D. A1 - Jin, Z. T1 - Effect of particle size gradation on the performance of glass-ceramic 3D printing process N2 - Particle size gradation is regarded as an effective method for overcoming the contradicting requirements in three-dimensional printing (3DP). In present work, particle size gradation was optimized to obtain both acceptable flowability of the powder material and high-strength 3D-printed glass-ceramic products. The effect of gradation on the printing process, sintering process and performance of the 3D-printed glass-ceramic products was investigated comprehensively. The glass-ceramic powders with three size ranges were mixed in certain proportions and applied to print parts. The result showed parts printed with powder mixed by 60 wt% 45–100 µm and 40 wt% 0–25 µm particles had satisfactory density of 1.60 g/cm³ and bending strength of 13.8 MPa. The flowability decreased with an increasing proportion of fine particles. Part density was determined by the powder bulk density in the powder bed as well as the shrinkage during sintering while strength of part was found to be dependent on the sintering degree. KW - Flowability KW - Glass-ceramic KW - Particle size gradation KW - Three-dimensional printing KW - Mechanical properties PY - 2017 DO - https://doi.org/10.1016/j.ceramint.2016.09.197 SN - 0272-8842 VL - 43 IS - 1 SP - 578 EP - 584 PB - Elsevier AN - OPUS4-39783 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -