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Mechanics of Composite Materials - The shapes of force–displacement curves recorded in single-fiber pullout and microbond tests are analyzed within the framework of a stress-based model of...  相似文献   
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We consider the problem of performing matrix completion with side information on row-by-row and column-by-column similarities. We build upon recent proposals for matrix estimation with smoothness constraints with respect to row and column graphs. We present a novel iterative procedure for directly minimizing an information criterion to select an appropriate amount of row and column smoothing, namely, to perform model selection. We also discuss how to exploit the special structure of the problem to scale up the estimation and model selection procedure via the Hutchinson estimator, combined with a stochastic Quasi-Newton approach. Supplementary material for this article is available online.  相似文献   
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In the last two decades, quantitative NMR (qNMR) has become increasingly important for the analysis of pharmaceuticals, chemicals, and natural products including dietary supplements. For the purpose of quality control and chemical standardization of a large variety of pharmaceutical, chemical, and medicinal products, qNMR has proven to be a valuable orthogonal quantification method and a compelling alternative to chromatographic techniques. This work reviews a fundamental component of the early development of qNMR, reflected in the pioneering work of the late George M. Hanna during the years between 1984 and 2006 at the US Food and Drug Administration (FDA). Because Hanna performed the majority of his groundbreaking work on a 90‐MHz instrument, his legacy output connects with recent progress in low‐field benchtop NMR instrumentation. Hanna gradually established the utility of qNMR for the routine quality control analyses practiced in pharmaceutical and related operations well ahead of his peers. His work has the potential to inspire new developments in qNMR applied to small molecules of biomedical importance.  相似文献   
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JPC – Journal of Planar Chromatography – Modern TLC - Commiphora mukul of the family Burseraceae, commonly known as guggul, is commonly used worldwide. The major phytoconstituents...  相似文献   
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We investigate the plasmonic response of gold nanospheres calculated using discrete dipole approximation validated against the results from other discretization methods, namely the finite-difference time-domain method and the finite-element methods. Comparisons are also made with calculations from analytical methods such as the Mie solution and the null-field method with discrete sources. We consider the nanoparticle interacting with the incident field both in free space and sitting on a planar substrate. In the latter case, discrete dipole approximation with surface interaction is used; this includes the interaction with the ‘image dipoles’ using Sommerfeld integration.  相似文献   
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ABSTRACT

RAPUNCL, a study course on Radionuclide Production with Cyclotrons, was organized in September 2017 in Mannheim. The intention was to test the feasibility of an educational program which is mainly driven by the input of the participating students. All aspects of target construction and operation have been covered in detail. Also the relevant aspects of Radiation Protection have been discussed. The students used intensively IAEA databases and MC simulation programs to model target design and operations. Topics for improvement have been identified and will be realized in the next course. Sources of funding have to be found to be able to organize the summer school in a sustainable way.  相似文献   
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