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971.
Birgit U. Jaki Anton Bzhelyansky Guido F. Pauli 《Magnetic resonance in chemistry : MRC》2021,59(1):7-15
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
972.
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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V. L. Y. Loke G. M. Huda E. U. Donev V. Schmidt J. T. Hastings M. Pinar Mengüç T. Wriedt 《Applied physics. B, Lasers and optics》2014,115(2):237-246
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
976.
ABSTRACTRAPUNCL, 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
977.
We investigate the resonant production of color octet muons in order to explore the discovery potential of Future Circular Collider(FCC)-based μp colliders.It is shown that the search potentials of μp colliders essentially surpass the potential of the LHC and would exceed that of the FCC pp collider. 相似文献
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A Collaboration M. Makek P. Achenbach C. Ayerbe Gayoso C. Barbieri J. C. Bernauer R. B?hm D. Bosnar A. Denig M. O. Distler I. Fri??i? C. Giusti H. Merkel U. Müller L. Nungesser J. Pochodzalla S. Sanches Majos B. S. Schlimme M. Schwamb Th. Walcher 《The European Physical Journal A - Hadrons and Nuclei》2016,52(9):298
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980.
Oxidative Addition of Haloheteroarenes to Palladium(0): Concerted versus SNAr‐Type Mechanism 下载免费PDF全文
Prof. Bert U. W. Maes Dr. Stefan Verbeeck Dr. Tom Verhelst Audrey Ekomié Niklas von Wolff Dr. Guillaume Lefèvre Dr. Emily A. Mitchell Prof. Anny Jutand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7858-7865
The kinetics of the oxidative additions of haloheteroarenes HetX (X=I, Br, Cl) to [Pd0(PPh3)2] (generated from [Pd0(PPh3)4]) have been investigated in THF and DMF and the rate constants have been determined. In contrast to the generally accepted concerted mechanism, Hammett plots obtained for substituted 2‐halopyridines and solvent effects reveal a reaction mechanism dependent on the halide X of HetX: an unprecedented SNAr‐type mechanism for X=Br or Cl and a classical concerted mechanism for X=I. These results are supported by DFT studies. 相似文献