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11.
Although the vibrational spectra of triphosphonitrilic chloride, (PNCl2)3 (1), have been studied by numerous investigators1–8, there is no general agreement about the frequency of completely inactive A2 ring vibration. Besides, assignment of some overtones and combination bands is doubtful. 相似文献
12.
Ohorodnik Yulia M. Alexander Sikalov A. Khomenko Dmytro M. Doroshchuk Roman O. Raspertova Ilona V. Shova Sergiu Babak Maria V. Lampeka Rostyslav D. 《Transition Metal Chemistry》2022,47(6):213-221
Transition Metal Chemistry - The structures of new p-cymene Ru(II) complexes with 2-(1-methyl-1H-1,2,4-triazol-3-yl)pyridine and 2-(1-methyl-1H-1,2,4-triazol-5-yl)pyridine were established based on... 相似文献
13.
Isaiah Adelabu Patrick TomHon Mohammad S. H. Kabir Shiraz Nantogma Mustapha Abdulmojeed Iuliia Mandzhieva Dr. Jessica Ettedgui Dr. Rolf E. Swenson Dr. Murali C. Krishna Prof. Thomas Theis Prof. Boyd M. Goodson Prof. Eduard Y. Chekmenev 《Chemphyschem》2022,23(2):e202100839
Signal Amplification By Reversible Exchange in SHield Enabled Alignment Transfer (SABRE-SHEATH) is investigated to achieve rapid hyperpolarization of 13C1 spins of [1-13C]pyruvate, using parahydrogen as the source of nuclear spin order. Pyruvate exchange with an iridium polarization transfer complex can be modulated via a sensitive interplay between temperature and co-ligation of DMSO and H2O. Order-unity 13C (>50 %) polarization of catalyst-bound [1-13C]pyruvate is achieved in less than 30 s by restricting the chemical exchange of [1-13C]pyruvate at lower temperatures. On the catalyst bound pyruvate, 39 % polarization is measured using a 1.4 T NMR spectrometer, and extrapolated to >50 % at the end of build-up in situ. The highest measured polarization of a 30-mM pyruvate sample, including free and bound pyruvate is 13 % when using 20 mM DMSO and 0.5 M water in CD3OD. Efficient 13C polarization is also enabled by favorable relaxation dynamics in sub-microtesla magnetic fields, as indicated by fast polarization buildup rates compared to the T1 spin-relaxation rates (e. g., ∼0.2 s−1 versus ∼0.1 s−1, respectively, for a 6 mM catalyst-[1-13C]pyruvate sample). Finally, the catalyst-bound hyperpolarized [1-13C]pyruvate can be released rapidly by cycling the temperature and/or by optimizing the amount of water, paving the way to future biomedical applications of hyperpolarized [1-13C]pyruvate produced via comparatively fast and simple SABRE-SHEATH-based approaches. 相似文献
14.
Aliev Ramiz A. Khomenko Irina A. Kormazeva Ekaterina S. 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):983-989
Journal of Radioanalytical and Nuclear Chemistry - Thin natEr2O3 targets were irradiated on cyclotron by 60 MeV alpha particles. Thulium and ytterbium radioisotopes, formed during... 相似文献
15.
Avinash Chettri Jan-Hendrik Kruse Keshav Kumar Jha Lara Dröge Dr. Iuliia Romanenko Dr. Christof Neumann Dr. Stephan Kupfer Prof. Dr. Andrey Turchanin Prof. Dr. Sven Rau Prof. Dr. Felix H. Schacher Prof. Dr. Benjamin Dietzek 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(68):17049-17058
Recently, porous photocatalytically active block copolymer membranes were introduced, based on heterogenized molecular catalysts. Here, we report the integration of the photosensitizer, i. e., the light absorbing unit in an intermolecular photocatalytic system into block copolymer membranes in a covalent manner. We study the resulting structure and evaluate the orientational mobility of the photosensitizer as integral part of the photocatalytic system in such membranes. To this end we utilize transient absorption anisotropy, highlighting the temporal reorientation of the transition dipole moment probed in a femtosecond pump-probe experiment. Our findings indicate that the photosensitizer is rigidly bound to the polymer membrane and shows a large heterogeneity of absolute anisotropy values as a function of location probed within the matrix. This reflects the sample inhomogeneity arising from different protonation states of the photosensitizer and different intermolecular interactions of the photosensitizers within the block copolymer membrane scaffold. 相似文献
16.
The increasing of yield of X-rays more than two times from femtosecond laser plasma produced in the target microchannel positioned
in air compared to the case from fresh target’s surface was registered and the angular dependence of output of X-rays was
firstly observed. 相似文献
17.
We reduce the problem on multiplicities of simple subquotients in an -stratified generalized Verma module to the analogous problem for classical Verma modules. 相似文献
18.
19.
Melting of an ultrathin lubricant film during friction between atomically smooth surfaces is studied. Additive noise of shear stress and strain as well as of film temperature is introduced and the phase diagram is constructed. On the diagram, the noise intensity for this temperature and the temperature of friction surfaces determine the regions of sliding, dry, and stick-slip friction. As a result of numerical analysis of the Langevin equation for various regions of the diagram, time series of stresses are constructed, which make it possible to explain the experiment on friction, in which intermittent motion is observed. Lubricant melting due to dissipative heating of friction surface is considered and the experimental time dependences of friction force are interpreted. 相似文献
20.
Yu. V. Maksimov V. V. Matveev I. P. Suzdalev T. I. Khomenko A. A. Kadushin 《Hyperfine Interactions》1990,57(1-4):1987-1990
The bimetallic catalysts obtained by the deposition of a Fe?Co binuclear cluster on the dehydroxylated γ-Al2O3 are studied and compared to some other relative systems. These bimetallic catalysts are found to be active and selective in olefin synthesis. This is connected with the formation of Fe?Co contact which is detectable by Mössbauer spectroscopy. 相似文献