TY - JOUR A1 - Westwood, S. A1 - Josephs, R. A1 - Choteau, T. A1 - Daireaux, A. A1 - Wielgosz, R. A1 - Davies, S. A1 - Moad, M. A1 - Chan, B. A1 - Munoz, A. A1 - Conneely, P. A1 - Ricci, M. A1 - Do Rego, E.C.P. A1 - Garrido, B.C. A1 - Violante, F.G.M. A1 - Windust, A. A1 - Dai, X. A1 - Huang, T. A1 - Zhang, W. A1 - Su, F. A1 - Quan, C. A1 - Wang, H. A1 - Lo, M. A1 - Wong, W. A1 - Gantois, F. A1 - Lalerle, B. A1 - Dorgerloh, Ute A1 - Koch, Matthias A1 - Klyk-Seitz, Urszula-Anna A1 - Pfeifer, Dietmar A1 - Philipp, Rosemarie A1 - Piechotta, Christian A1 - Recknagel, Sebastian A1 - Rothe, Robert A1 - Yamazaki, T. A1 - Zakaria, O. B. A1 - Castro, E. A1 - Balderas, M. A1 - González, N. A1 - Salazar, C. A1 - Regalado, L. A1 - Valle, E. A1 - Rodríguez, L. A1 - Laguna, L.Á.. A1 - Ramírez, P. A1 - Avila, M. A1 - Ibarra, J. A1 - Valle, L. A1 - Arce, M. A1 - Mitani, Y. A1 - Konopelko, L. A1 - Krylov, A. A1 - Lopushanskaya, E. A1 - Lin, T.T. A1 - Liu, Q. A1 - Kooi, L.T. A1 - Fernandes-Whaley, M. A1 - Prevoo-Franzsen, D. A1 - Nhlapo, N. A1 - Visser, R. A1 - Kim, B. A1 - Lee, H. A1 - Kankaew, P. A1 - Pookrod, P. A1 - Sudsiri, N. A1 - Shearman, K. A1 - Gören, A.C. A1 - Bilsel, G. A1 - Yilmaz, H. A1 - Bilsel, M. A1 - Cergel, M. A1 - Coskun, F.G. A1 - Uysal, E. A1 - Gündüz, S. A1 - Ün, I. A1 - Warren, J. A1 - Bearden, D.W. A1 - Bedner, M. A1 - Duewer, D.L. A1 - Lang, B.E. A1 - Lippa, K.A. A1 - Schantz, M.M. A1 - Sieber, J.R. T1 - Final report on key comparison CCQM-K55.c (L-(+)-Valine): Characterization of organic substances for chemical purity N2 - KEY COMPARISON Under the auspices of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a key comparison, CCQM K55.c, was coordinated by the Bureau International des Poids et Mesures (BIPM) in 2012. Twenty National Measurement Institutes or Designated Institutes and the BIPM participated. Participants were required to assign the mass fraction of valine present as the main component in the comparison sample for CCQM-K55.c. The comparison samples were prepared from analytical grade L-valine purchased from a commercial supplier and used as provided without further treatment or purification. Valine was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of organic compounds of low structural complexity [molecular weight range 100–300] and high polarity (pKOW > –2). The KCRV for the valine content of the material was 992.0 mg/g with a combined standard uncertainty of 0.3 mg/g. The key comparison reference value (KCRV) was assigned by combination of KCRVs assigned from participant results for each orthogonal impurity class. The relative expanded uncertainties reported by laboratories having results consistent with the KCRV ranged from 1 mg/g to 6 mg/g when using mass balance based approaches alone, 2 mg/g to 7 mg/g using quantitative 1H NMR (qNMR) based approaches and from 1 mg/g to 2.5 mg/g when a result obtained by a mass balance method was combined with a separate qNMR result. The material provided several analytical challenges. In addition to the need to identify and quantify various related amino acid impurities including leucine, isoleucine, alanine and a-amino butyrate, care was required to select appropriate conditions for performing Karl Fischer titration assay for water content to avoid bias due to in situ formation of water by self-condensation under the assay conditions. It also proved to be a challenging compound for purity assignment by qNMR techniques. There was overall excellent agreement between participants in the identification and the quantification of the total and individual related structure impurities, water content, residual solvent and total non-volatile content of the sample. Appropriate technical justifications were developed to rationalise observed discrepancies in the limited cases where methodology differences led to inconsistent results. The comparison demonstrated that to perform a qNMR purity assignment the selection of appropriate parameters and an understanding of their potential influence on the assigned value is critical for reliable implementation of the method, particularly when one or more of the peaks to be quantified consist of complex multiplet signals. PY - 2014 DO - https://doi.org/10.1088/0026-1394/51/1A/08010 SN - 0026-1394 SN - 1681-7575 VL - 51 SP - 08010, 1 EP - 44 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-31072 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Westwood, S. A1 - Josephs, R. A1 - Choteau, T. A1 - Daireaux, A. A1 - Stoppacher, N. A1 - Wielgosz, R. A1 - Davies, S. A1 - do Rego, E. A1 - Wollinger, W. A1 - Garrido, B. A1 - Fernandes, J. A1 - Lima, J. A1 - Oliveira, R. A1 - de Sena, R. A1 - Windust, A. A1 - Huang, T. A1 - Dai, X. A1 - Quan, C. A1 - He, H. A1 - Zhang, W. A1 - Wei, C. A1 - Li, N. A1 - Gao, D. A1 - Liu, Z. A1 - Lo, M. A1 - Wong, W. A1 - Pfeifer, Dietmar A1 - Koch, Matthias A1 - Dorgerloh, Ute A1 - Rothe, Robert A1 - Philipp, Rosemarie A1 - Hanari, N. A1 - Rezali, M. A1 - Arzate, C. A1 - Berenice, M. A1 - Caballero, V. A1 - Osuna, M. A1 - Krylov, A. A1 - Kharitonov, S. A1 - Lopushanskaya, E. A1 - Liu, Q. A1 - Lin, T. A1 - Fernandes-Whaley, M. A1 - Quinn, L. A1 - Nhlapo, N. A1 - Prevoo-Franzsen, D. A1 - Archer, M. A1 - Kim, B. A1 - Baek, S. A1 - Lee, S. A1 - Lee, J. A1 - Marbumrung, S. A1 - Kankaew, P. A1 - Chaorenpornpukdee, K. A1 - Chaipet, T. A1 - Shearman, K. A1 - Gören, A. A1 - Gündüz, S. A1 - Yilmaz, H. A1 - Un, I. A1 - Bilsel, G. A1 - Clarkson, C. A1 - Bedner, M. A1 - Camara, J. A1 - Lang, B. A1 - Lippa, K. A1 - Nelson, M. A1 - Toman, B. A1 - Yu, L. T1 - Mass fraction assignment of folic acid in a high purity material - CCQM-K55.d (Folic acid) Final Report N2 - The comparison required the assignment of the mass fraction of folic acid present as the main component in the comparison sample. Performance in the comparison is representative of a laboratory's measurement capability for the purity assignment of organic compounds of medium structural complexity [molecular weight range 300–500] and high polarity (pKOW < −2). Methods used by the eighteen participating NMIs or DIs were based on a mass balance (summation of impurities) or qNMR approach, or the combination of data obtained using both methods. The qNMR results tended to give slightly lower values for the content of folic acid, albeit with larger associated uncertainties, compared with the results obtained by mass balance procedures. Possible reasons for this divergence are discussed in the report, without reaching a definitive conclusion as to their origin. The comparison demonstrates that for a structurally complex polar organic compound containing a high water content and presenting a number of additional analytical challenges, the assignment of the mass fraction content property value of the main component can reasonably be achieved with an associated relative standard uncertainty in the assigned value of 0.5% KW - CCQM key comparison KW - Purity assessment KW - Folic acid PY - 2018 UR - https://www.bipm.org/utils/common/pdf/final_reports/QM/K55/CCQM-K55.d.pdf DO - https://doi.org/10.1088/0026-1394/55/1A/08013 VL - 55 IS - Technical Supplement, 2018 SP - 08013, 1 EP - 38 PB - Institute of Physics Publishing (IOP) ; Bureau International des Poids et Mesures AN - OPUS4-44999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Li, X.M. A1 - Li, H.M. A1 - Zhang, Q.H. A1 - Lu, X.H. A1 - Li, S.Q. A1 - Koch, Matthias A1 - Polzer, J. A1 - Hackenber, R. A1 - Moniruzzaman, M. A1 - Khan, M. A1 - Kakoulides, E. A1 - Pak-Wing, K. A1 - Richy, A1 - Chi-Shing, N. A1 - Lu, T. A1 - Gui, E.M. A1 - Cheow, P.S. A1 - Teo, T.L. A1 - Rego, E. A1 - Garrido, B. A1 - Carvalho, L. A1 - Leal, R. A1 - Violante, F. A1 - Baek, S.Y. A1 - Lee, S. A1 - Choi, K. A1 - Kim, B. A1 - Bucar-Miklavcic, M. A1 - Hopley, C. A1 - Nammoonnoy, J. A1 - Murray, J. A1 - Wilson, W. A1 - Toman, B. A1 - Itoh, N. A1 - Gokcen, T. A1 - Krylov, A. A1 - Mikheeva, A. T1 - CCQM-K146 low-polarity analyte in high fat food: benzo a pyrene in olive oil N2 - The demonstration of competency and equivalence for the assessment of levels of contaminants and nutrients in primary foodstuffs is a priority within the 10-year strategy for the OAWG Track A core comparisons. The measurements are core challenges for reference material producers and providers of calibration Services. This key comparison related to low polarity analytes in a high fat, low protein, low carbohydrate food matrix and Benzo[a]pyrene in edible oil was the model System selected to align with this class within the OAWG strategy. Evidence of successful participation in formal, relevant international comparisons is needed to document measurement capability claims (CMCs) made by national metrology institutes (NMIs) and designated institutes (Dis). 16 National Metrology Institutions participated in the Track A Key Comparison CCQM-K146 Low-Polarity Analyte in high fat food: Benzo[a]pyrene in Olive Oil. Participants were requested to evaluate the mass fractions, expressed in µg/kg, of Benzo[a]pyrene in the olive oil material. The KCRV was determined from the results of all NMIs/DIs participating in the key comparison that used appropriately validated methods with demonstrated metrological traceability. Different methods such as liquid-liquid extraction, GPC and SPE were applied in the sample pretreatment and HPLC-FLD, HPLC-MS/MS, and GC-MS or GC-MS/MS were applied for detection by the participants. The mass fractions for BaP were in the range of (1.78 to 3.09) µg/kg with Standard uncertainties of (0.026 to 0.54) µg/kg, with corresponding relative Standard uncertainties from 0.9% to 21%. Five labs withdrew their result from the Statistical evaluation of the KCRV for technical reasons. One lab was excluded from the KCRV evaluation, as they did not meet the CIPM metrological traceability requirements. A Hierarchical Bayes option was selected for the KCRV value, which was determined as 2.74 µg/kg with a Standard uncertainty of 0.03 µg/kg. The 10 institutes those were included in the calculation of the consensus KCRV all agreed within their Standard uncertainties. Successful participation in CCQM-K146 demonstrates the measurement capabilities in determining mass fraction of organic compounds, with molecular mass of 100 g/mol to 500 g/mol, having low polarity pKow < -2, in mass fraction range from 0.1 µg/kg to 1000 µg/kg in a high fat, low protein, low carbohydrate food matrix. KW - Metrology KW - CCQM KW - Food KW - PAH PY - 2020 DO - https://doi.org/10.1088/0026-1394/57/1a/08017 VL - 57 IS - 1a SP - 08017 AN - OPUS4-52435 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rothbart, Nick A1 - Maierhofer, Christiane A1 - Goldammer, M. A1 - Hohlstein, F. A1 - Koch, J. A1 - Kryukov, I. A1 - Mahler, G. A1 - Stotter, B. A1 - Walle, G. A1 - Oswald-Tranta, B. A1 - Sengebusch, M. T1 - A round robin test on flash thermography N2 - A round robin test on flash thermography was organized within the scope of a standardization research project. This test gives information on reliability, comparability and efficiency of different testing situations. Data recorded on metal and CFRP test specimens with flat bottom holes (FBH) were analysed by evaluating the detectability and by calculating the signal-to-noise ratio (SNR) of the defect signatures as a function of defect parameters. For the investigation of the influence of material properties on the spatial resolution as well as on penetration depth, test specimens made of steel and copper with crossed notches and a notch ramp were constructed and investigated. Here, the minimum resolvable notch distance and the maximum detectable depth of the ramp were analysed. T2 - 19th World Conference on Non-destructive Testing (WCNDT) CY - Munich, Germany DA - 13.06.2016 KW - Active thermography KW - Flash excitation KW - Round robin test KW - Standardisation PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-366853 SN - 978-3-940283-78-8 VL - BB 158 SP - We.3.D.4., 1 EP - 8 PB - DGZfP CY - Berlin AN - OPUS4-36685 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rothbart, Nick A1 - Maierhofer, Christiane A1 - Goldammer, M. A1 - Hohlstein, F. A1 - Koch, J. A1 - Kryukov, I. A1 - Mahler, G. A1 - Stotter, B. A1 - Walle, G. A1 - Oswald-Tranta, B. A1 - Sengebusch, M. T1 - Probability of detection analysis of round robin test results performed by flash thermography N2 - Within the scope of a standardisation research project, a flash thermography round robin test that evaluates reliability, comparability and efficiency of different testing situations was performed. Data recorded at metal test specimens with flat bottom holes (FBHs) were analysed by calculating the signal-to-noise ratio (SNR) of the defect signatures in the thermograms as well as in the phase images as a function of defect parameters. A new multi-parameter probability of detection (POD) model was developed, where an â versus a continuous signal analysis was based on the linear relationship between the SNR and a multi-parameter a. This linear relationship was verified by comparison to data obtained from an analytical model that is considering lateral thermal heat diffusion as well as to data obtained by numerical simulation. The resulting POD curves for the thermograms and phase images give an estimation for the detectability of the FBHs with known geometry in steel using different equipment and obtained by different participants. By comparing the SNRs of FBHs with similar geometries, this POD model was transferred to aluminium and copper as well. KW - Active thermography KW - Flash excitation KW - Signal-to-noise ratio KW - Round robin test KW - Multi-parameter POD PY - 2016 UR - http://www.tandfonline.com/doi/full/10.1080/17686733.2016.1229246 DO - https://doi.org/10.1080/17686733.2016.1229246 SN - 1768-6733 SN - 2116-7176 VL - 14 IS - 1 SP - 1 EP - 23 PB - Taylor and Francis CY - Abingdon, UK AN - OPUS4-38192 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rothbart, Nick A1 - Maierhofer, Christiane A1 - Goldammer, M. A1 - Hohlstein, F. A1 - Koch, J. A1 - Kryukov, I. A1 - Mahler, G. A1 - Stotter, B. A1 - Oswald-Tranta, B. A1 - Sengebusch, M. T1 - A round robin test of flash thermography of CFRP and metal structures N2 - Within the scope of a DIN INS project, a flash thermography round robin test that evaluates reliability, comparability and efficiency of different testing situations is organized. The results give information about the detectability of defects e.g. by their size and depth, the evaluation method and by the materials used. Besides, the influence of equipment and parameters used by the participants on the results were analysed. All of the quantitative results as well as the feedback given by the participants will be presented in a DIN committee in order to contribute to a flash thermography standard. T2 - 7th International Symposium on NDT in Aerospace CY - Bremen, Germany DA - 16.11.2015 KW - Flash thermography KW - Round robin test KW - Metal KW - Flat bottom holes KW - SNR PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351070 UR - https://www.ndt.net/?id=18921 SN - 1435-4934 VL - 21 IS - 4 SP - 1 EP - 8 PB - NDT.net CY - Kirchwald AN - OPUS4-35107 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maierhofer, Christiane A1 - Rothbart, Nick A1 - Goldammer, M. A1 - Hohlstein, F. A1 - Koch, J. A1 - Kryukov, I. A1 - Mahler, G. A1 - Stotter, B. A1 - Walle, G. A1 - Oswald-Tranta, B. A1 - Sengebusch, M. T1 - A round robin test of flash thermography – detectability and quantification of artificial and natural defects in CFRP and metal structures N2 - Within the scope of a DIN INS project, a flash thermography round robin test that evaluates reliability, comparability, and efficiency of different testing situations was organized. The results give information about the detectability of defects, e.g. depending on their size and depth, the evaluation methods and the materials used. Besides, the influences of equipment and parameters used by the participants on the results were analysed. All of the quantitative results as well as the feedback given by the participants will be presented in a DIN committee in order to contribute to a flash thermography standard. T2 - Conference QIRT 2016 CY - Gdansk, Poland DA - 04.07.2016 KW - Active thermography KW - Flash excitation KW - Round robin test KW - CFRP KW - Metal PY - 2016 UR - http://qirt.gel.ulaval.ca/archives/qirt2016/papers/075.pdf DO - https://doi.org/10.21611/qirt.2016.075 SN - 2371-4085 SP - Paper 075, 517 EP - 526 CY - Quebec, Canada AN - OPUS4-37510 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Warth, B. A1 - Kant, Jill-Sandra A1 - Schebb, N.H. A1 - Krska, R. A1 - Koch, Matthias A1 - Sulyok, M. T1 - Investigation of the hepatic glucuronidation pattern of the fusarium mycotoxin deoxynivalenol in various species N2 - Deoxynivalenol (DON) is one of the most abundant mycotoxins contaminating food and feed worldwide. Upon absorption, the major portion of the toxin is excreted by humans and animal species as glucuronide. However, consistent in vitro data on DON glucuronidation are lacking. In the present study, the metabolism of DON was investigated using liver microsomes from humans and six different animal species. It was shown that all animal and human liver microsomes led to the formation of up to three different mono-O-glucuronides with significant interspecies differences. While the activity of human liver microsomes was low (0.8 to 2.2 pmol·min–1·mg–1), bovine liver and rat liver microsomes conjugated DON with activities of 525 pmol·min–1·mg–1 and 80 pmol·min–1·mg–1, respectively. KW - Deoxynivalenol KW - Hepatic metabolism KW - Microsomes KW - Glucuronidation KW - Inter-species comparison PY - 2012 DO - https://doi.org/10.1021/tx300348x SN - 0893-228X SN - 1520-5010 VL - 25 IS - 12 SP - 2715 EP - 2717 PB - Soc. CY - Washington, DC, USA AN - OPUS4-27604 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tiebe, Carlo A1 - Miessner, H. A1 - Koch, B. A1 - Hübert, Thomas T1 - Detection of microbial volatile organic compounds (MVOCs) by ion-mobility spectrometry N2 - Traces of microbial volatile organic compounds (MVOCs) in air can indicate the presence of growth of moulds in the indoor environment. Ion-mobility spectrometry is a very promising method for detection of these MVOCs, because of its high sensitivity. For development of an in-situ method for detection of MVOCs, a portable ion-mobility spectrometer (IMS) was used and test gases of 14 MVOCs and their respective mixtures were investigated. IMS spectra were recorded as a function of concentration of MVOCs in air. Drift time and mobility of reactant ions formed in positive polarity mode were determined and correlated with the mass-to-charge ratio (m/z) of the MVOCs investigated. The estimated detection limit has a specific value for each MVOC and is in the range 3 to 96 µg m-3 (1 to 52 ppbV). Indoor trials show that IMS can indicate hidden mould growth. KW - Trace gas analysis KW - MVOCs KW - Ion-mobility spectrometry KW - Mould detection PY - 2009 DO - https://doi.org/10.1007/s00216-009-3147-4 SN - 1618-2642 SN - 1618-2650 VL - 395 IS - 7 SP - 2313 EP - 2323 PB - Springer CY - Berlin AN - OPUS4-20082 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Skrotzki, Birgit A1 - Koch, B. T1 - Microstructural characterization of the metastable Beta-titanium alloy TIMETAL LCB after fatigue loading N2 - In the present work, the titanium alloy Ti-6.8Mo-4.5Fe-1.5Al (Timetal LCB) was investigated with respect to the microstructural evolution during strain controlled fatigue loading. The alloy was developed to reduce the generally high material costs of β-alloys by substituting expensive beta stabilizers by using a standard Fe-Mo master alloy. One possible application seen in the automotive industry is the substitution os suspension structural parts currently made of steel, suc as suspension springs. These components require a high strength and fatigue resistance. T2 - International conference on electron nanoscopy & XXXII Annual meeting of EMSI CY - Hyderabad, India DA - 2011-07-06 KW - Titanium KW - Fatigue KW - Microstructure KW - Deformation mechanism PY - 2011 SP - 255 EP - 256 AN - OPUS4-24167 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krumbholz, N. A1 - Jansen, A. A1 - Scheller, M. A1 - Müller-Wirts, T. A1 - Lübbecke, S. A1 - Holzwarth, R. A1 - Scheunemann, R. A1 - Wilk, R. A1 - Sartorius, B. A1 - Roehle, H. A1 - Stanze, D. A1 - Beckmann, Jörg A1 - von Chrzanowski, Lars A1 - Ewert, Uwe A1 - Koch, M. ED - Keith A. Krapels, ED - Neil A. Salmon, T1 - Handheld terahertz spectrometer for the detection of liquid explosives N2 - We present a handheld fiber-coupled terahertz spectrometer operating at a center wavelength of 1550 nm. The key elements are a fs-fiber laser, a fiber stretcher delay line and fiber-coupled antennas, which contain novel InAlAs-InGaAs multi layer chips. First experimental data obtained with this system demonstrates its great potential and robustness. In addition, we investigate different hazardous and harmless liquids in reflection geometry. These experiments show that liquids are in principle distinguishable by terahertz spectroscopy. Finally, first steps towards an algorithm that allows for an extraction of the liquids dielectric properties are discussed. The algorithm works for the analysis of reflection data even if the liquid is located inside a container. KW - Handheld terahertz spectrometer KW - Liquid explosives PY - 2009 DO - https://doi.org/10.1117/12.830381 SN - 0277-786X VL - 7485 SP - 748504-1 - 748504-12 AN - OPUS4-20268 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Faust, R. A1 - Nauroozi, D. A1 - Bruhn, C. A1 - Koch, B. A1 - Kuhlich, Paul A1 - Piechotta, Christian A1 - Nehls, Irene T1 - (3,5,5,6,8,8-Hexamethyl-5,6,7,8-tetrahydronaphthalen-2-yl)methanol: a possible metabolite of the synthetic musk fragrance AHTN N2 - The title compound (AHTN-OH), C17H26O, was prepared in order to provide standard materials for the qualitative and quantitative analysis of environmental pollutants. The molecule possesses a chiral C atom, although the structure determination was performed on racemic material, expressed in the structure as disordered chiral sites. The asymmetric unit consists of four AHTN-OH molecules containing an hydroxy group and forming a tetrameric cyclic motif built up by four strong hydrogen bonds between these hydroxy groups and additionally by two weak C–H···π interactions. Furthermore, these tetramers are linked via very weak C–H···π interactions, forming chains along the c axis. PY - 2011 DO - https://doi.org/10.1107/S1600536811018009 SN - 1600-5368 VL - 67 SP - o1462-o1463, sup1-15 PB - Munksgaard CY - Copenhagen AN - OPUS4-24310 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rothbart, Nick A1 - Maierhofer, Christiane A1 - Röllig, Mathias A1 - Sengebusch, M. A1 - Goldammer, M. A1 - Hohlstein, F. A1 - Koch, J. A1 - Kryukov, I. A1 - Mahler, G. A1 - Stotter, B. A1 - Walle, G. T1 - Ringversuche zur Blitzthermografie N2 - Im Rahmen des INS-Projekts „Durchführung von Ringversuchen zur Normung und Standardisierung der aktiven Thermografie mit Blitzlichtanregung“ wurden Ringversuche durchgeführt, die die Zuverlässigkeit, Vergleichbarkeit und Effektivität der Blitzthermografie für unterschiedliche Prüfprobleme nachweisen sollten. Weiterhin sollten diese Untersuchungen als Methodenvalidierungsstudie die Richtigkeit und Präzision der Blitzthermografie nachweisen und Vergleichsinformationen unterschiedlicher Geräteausstattungen liefern. Im Normausschuss NA 062-08-27 AA „Visuelle und thermografische Prüfung“ des DIN werden die Ergebnisse die Erarbeitung eines Normentwurfs zur Blitzthermografie unterstützen. In diesem Beitrag werden die Ringversuche beschrieben und ausgewählte Ergebnisse präsentiert. T2 - Thermographie-Kolloquium 2015 CY - Leinfelden-Echterdingen, Germany DA - 01.10.2015 KW - Thermografie mit Blitzanregung KW - Ringversuch KW - Testkörper KW - Standardisierung KW - Signal-zu-Rausch-Verhältnis PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-345460 SN - 978-3-940283-74-0 IS - DGZfP BB 154 SP - Vortrag 12, 1 EP - 8 AN - OPUS4-34546 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Warth, B. A1 - Schebb, N.H. A1 - Krska, R. A1 - Koch, Matthias A1 - Sulyok, M. T1 - In vitro glucuronidation kinetics of deoxynivalenol by human and animal microsomes and recombinant human UGT enzymes N2 - The mycotoxin deoxynivalenol (DON), formed by Fusarium species, is one of the most abundant mycotoxins contaminating food and feed worldwide. Upon ingestion, the majority of the toxin is excreted by humans and animal species as glucuronide conjugate. First in vitro data indicated that DON phase II metabolism is strongly species dependent. However, kinetic data on the in vitro metabolism as well as investigations on the specific enzymes responsible for DON glucuronidation in human are lacking. In the present study, the DON metabolism was investigated using human microsomal fractions and uridine-diphosphoglucuronyltransferases (UGTs) as well as liver microsomes from five animal species. Only two of the twelve tested human recombinant UGTs led to the formation of DON glucuronides with a different regiospecificity. UGT2B4 predominantly catalyzed the formation of DON-15-O-glucuronide (DON-15GlcA), while for UGT2B7 the DON-3-O-glucuronide (DON-3GlcA) metabolite prevailed. For human UGTs, liver, and intestinal microsomes, the glucuronidation activities were low. The estimated apparent intrinsic clearance (Clapp,int) for all human UGT as well as tissue homogenates was <1 mL/min mg protein. For the animal liver microsomes, moderate Clapp,int between 1.5 and 10 mL/min mg protein were calculated for carp, trout, and porcine liver. An elevated glucuronidation activity was detected for rat and bovine liver microsomes leading to Clapp,int between 20 and 80 mL/min mg protein. The obtained in vitro data points out that none of the animal models is suitable for estimating the human DON metabolism with respect to the metabolite pattern and formation rate. KW - Deoxynivalenol KW - Glucuronidation KW - Uridine-diphosphoglucuronyltransferases (UGT) KW - Human recombinant UGT KW - Trichothecene KW - Phase II metabolism PY - 2015 DO - https://doi.org/10.1007/s00204-014-1286-7 SN - 0340-5761 SN - 1432-0738 VL - 89 IS - 6 SP - 949 EP - 960 PB - Springer CY - Berlin ; Heidelberg [u.a.] AN - OPUS4-33204 LA - eng 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 - Schmack, R. A1 - Eckhardt, B. A1 - Koch, G. A1 - Ortel, Erik A1 - Kraehnert, R. T1 - ZnO coatings with controlled pore size, crystallinity and electrical conductivity N2 - Zinc oxide is a wide bandgap semiconductor with unique optical, electrical and catalytic properties. Many of its practical applications rely on the materials pore structure, crystallinity and electrical conductivity. We report a synthesis method for ZnO films with ordered mesopore structure and tuneable crystallinity and electrical conductivity. The synthesis relies on dip-coating of solutions containing micelles of an amphiphilic block copolymer and complexes of Zn2+ ions with aliphatic ligands. A subsequent calcination at 400 °C removes the template and induces crystallization of the pore walls. The pore structure is controlled by the template polymer, whereas the aliphatic ligands control the crystallinity of the pore walls. Complexes with a higher thermal stability result in ZnO films with a higher content of residual carbon, smaller ZnO crystals and therefore lower electrical conductivity. The paper discusses the ability of different types of ligands to assist in the synthesis of mesoporous ZnO and relates the structure and thermal stability of the precursor complexes to the crystallinity and electrical conductivity of the zinc oxide. KW - conductivity KW - EISA KW - pore templating KW - pore size control KW - ligands KW - zinc oxide PY - 2016 DO - https://doi.org/10.5755/j01.ms.22.1.8634 SN - 1392–1320 VL - 22 IS - 1 SP - 74 EP - 81 PB - Kaunas University of Technology, Lithuania AN - OPUS4-35550 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - El-Khatib, A. H. A1 - Radbruch, H. A1 - Trog, S. A1 - Neumann, B. A1 - Paul, F. A1 - Koch, A. A1 - Linscheid, M. W. A1 - Jakubowski, Norbert A1 - Schellenberger, E. T1 - Gadolinium in human brain sections and colocalization with other elements N2 - Recent recommendations by the Food and Drug Administration1 and the European Medicines Agency2 are to limit the clinical use of linear gadolinium-based contrast agents (GBCAs) due to convincing evidence of deposition in tissues. Macrocyclic GBCA continued to be considered safe, provided that patients have normal renal function. To date, given the low sensitivity of conventional MRI, there has been a debate about the signal increase following the injections of a macrocyclic GBCA. KW - Gadolinium PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-471309 DO - https://doi.org/10.1212/NXI.0000000000000515 SN - 2332-7812 VL - 6 IS - 1 SP - e515, 1 EP - 3 PB - American Academy of Neurology AN - OPUS4-47130 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tiebe, Carlo A1 - Hübert, Thomas A1 - Koch, B. A1 - Ritter, U. A1 - Stephan, Ina T1 - Investigation of gaseous metabolites from moulds by ion mobility spectrometry (IMS) and gas chromatography-mass spectrometry (GC-MS) N2 - The metabolism of moulds results in the formation of various microbial volatile organic compounds (MVOCs). These substances can be used as an indicator for the presence of moulds in the indoor environment. Three different mould strains were cultivated on culture media and IMS spectra of gaseous mould metabolites were recorded using a portable mini system with a tritium source and a 5 cm drift cell. The headspace spectra are characteristic for mould species and their age. Typical gaseous components of the metabolites were identified and compared with results obtained from gas chromatography using a mass spectrometer detector. It was observed that the MVOCs formation depends on mould species and their growing stage with a maximum of MVOCs emission occurring during the first 10 days. These preliminary results show that IMS can be applied to detect MVOCs in indoor environment and indicate hidden mould growth. KW - Mould detection KW - MVOC KW - Biochemical sensor system KW - Ion mobility spectrometry KW - IMS KW - Gas chromatography KW - Mass spectrometry KW - Principal component analysis PY - 2010 DO - https://doi.org/10.1007/s12127-009-0035-8 SN - 1435-6163 VL - 13 IS - 1 SP - 17 EP - 24 PB - Springer CY - Berlin; Heidelberg AN - OPUS4-21234 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hübert, Thomas A1 - Tiebe, Carlo A1 - Stephan, Ina A1 - Miessner, H. A1 - Koch, B. T1 - Detection of mould in indoor environments using a mini ion-mobility spectrometer system T2 - EUROSENSORS XXII CY - Dresden, Germany DA - 2008-10-07 KW - Mould detection KW - Fungus KW - Indoor air quality KW - MVOC KW - Biochemical sensor system KW - Ion-mobility spectrometry PY - 2008 SN - 978-3-00-025217-4 SP - 300 EP - 303 AN - OPUS4-18186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -