TY - JOUR A1 - Herrmann, K. A1 - Pech May, Nelson Wilbur A1 - Retsch, M. T1 - Photoacoustic thermal characterization of low thermal diffusivity thin films N2 - The photoacoustic measurement technique is a powerful yet underrepresented method to characterize the thermal transport properties of thin films. For the case of isotropic low thermal diffusivity samples, such as glasses or polymers, we demonstrate a general approach to extract the thermal conductivity with a high degree of significance. We discuss in particular the influence of thermal effusivity, thermal diffusivity, and sample layer thickness on the significance and accuracy of this measurement technique. These fundamental thermal properties guide sample and substrate selection to allow for a feasible thermal transport characterization. Furthermore, our data evaluation allows us to directly extract the thermal conductivity from this transient technique, without separate determination of the volumetric heat capacity, when appropriate boundary conditions are fulfilled. Using silica, poly(methyl methacrylate) (PMMA) thin films, and various substrates (quartz, steel, and silicon), we verify the quantitative correctness of our analytical approach. KW - Thermal conductivity KW - Photoacoustic characterization KW - Thin film characterization PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528743 DO - https://doi.org/10.1016/j.pacs.2021.100246 SN - 2213-5979 VL - 22 SP - 100246 PB - Elsevier AN - OPUS4-52874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zscherpel, Uwe T1 - Update on revision of ISO 24497 - NDT - Metal Magnetic Memory N2 - This presentation given at the Commission V meeting during the IIW annual assembly 2017 in Shanghai refects the work done so far to revise ISO 24497:2007. Suggestions were presented how to solve the discrepancies betwenn the involved contries. The action plan to finalize this revision was fixed. T2 - IIW Annual Assembly 2017 CY - Shanghai, China DA - 25.06.2017 KW - NDT KW - Magnetic Memory Method KW - ISO standard revision PY - 2017 AN - OPUS4-41138 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meyer, Klas T1 - Interlaboratory Comparison of Low-Field NMR Spectrometers – Purities at 200 and 10 mmol/L - Preliminary Results N2 - Due to its advantages of being a direct comparison method, quantitative NMR spectroscopy (qNMR) becomes more and more popular in industry. While conventional high-field NMR systems are often associated with high investment and operational costs, the upcoming market of permanent-magnet based benchtop NMR systems show a considerable option for a lot of applications. The mobility of these systems allows to bring them more closely to the real production environment, e.g. for at-line quality control. In this work we present an interlaboratory comparison study investigating the qNMR performance of state-of-the-art benchtop NMR spectrometers. Therefore, BAM prepared two samples of a mixture of NMR reference standards tetramethylbenzene (TMB) and tetrachloronitrobenzene (TCNB) at concentration levels of 200 mM and 10 mM. These “ready-to-use” samples were sent to participant laboratories, which performed analysis on their benchtop NMR equipment of different vendors and fields from 43 to 80 MHz. Raw data was reported back and further investigated by using different data analysis methods at BAM. After this very first qNMR comparison study of benchtop NMR spectrometers show promising results, following studies are planned to cover more parts of the qNMR process, e.g. sample preparation and weighing, but also data analysis, as commonly done in similar studies for high-field NMR spectroscopy in industry and metrology. T2 - 7th Practical Applications of NMR in Industry Conference (PANIC) CY - Hilton Head Island, SC, USA DA - 04.03.2019 KW - qNMR KW - Benchtop NMR KW - Interlaboratory Comparison PY - 2019 AN - OPUS4-47512 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -