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101.
Dzhumazoda A. Panina L. V. Nematov M. G. Yudanov N. A. Tabarov F. S. Morchenko A. T. Ukhasov A. A. 《Technical Physics》2019,64(7):990-993
Technical Physics - Further miniaturization of magnetic electron devices and devices of microsystem engineering in many ways depends on the optimal choice of functional materials (media) used in... 相似文献
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Valerii N. Snytnikov Tatyana I. Mishchenko Vladimir N. Snytnikov Sergei E. Malykhin Vasilii I. Avdeev Valentin N. Parmon 《Research on Chemical Intermediates》2012,38(3-5):1133-1147
Homogeneous gas-phase pyrolysis of ethane by continuous CO2 laser irradiation was used in our experiments for bulk heating of the reaction mixture. Laser energy was absorbed by ethylene, the main product of ethane dehydrogenation, and transferred to the reaction medium via collisional relaxation. A mechanism of ethane dehydrogenation is suggested to describe the pyrolysis process. The mechanism is autocatalytic in respect of ethylene and includes ethane?Cethylene interaction with the formation of methyl and propyl radicals. Rate constants of elementary reactions, selectivity, and yields of pyrolysis products were determined. The composition of ethane dehydrogenation products determined in the experiments was substantially different from the calculated thermodynamic equilibrium composition. 相似文献
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Michael McIntire Liang Zhao Valerii Kobryanskii Eric Chronister 《Journal of Raman spectroscopy : JRS》2011,42(6):1435-1441
The pressure‐induced Raman shifts of six vibrational bands of 20% and 50% trans‐polyacetylene nanoparticles in poly(vinyl‐butyral) matrix films (NPA/PVB) were studied from 0 to 45 kbar using a diamond anvil cell (DAC). The Raman shifts did not depend on the thickness of the two samples studied. Two of the vibrational bands displayed peak positions that depended on the isomeric compositions, with the 20% trans‐NPA/PVB bands being slightly blue‐shifted relative to the 50% trans‐NPA/PVB bands over the 45 kbar pressure range. The Raman bands of NPA/PVB associated with the trans form initially exhibited a relatively large shift at low pressures (P < 10 kbar) along with a drastic change in their band profile. In order to investigate the relative shielding of the vibrational modes studied, a Grüneisen analysis of the pressure‐induced shifts was conducted by estimating the parameters of the Murnaghan equation of state for solid polyacetylene (PA). Four of the six vibrational modes were found to be sensitive to compression of the interchain void space, while the other two modes were insensitive, indicating that they are relatively shielded from the compression of the sample. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Pidpruzhnykov YV Sabko VE Iurchenko VV Zupanets IA 《Biomedical chromatography : BMC》2012,26(5):599-605
A rapid and simple method based on ultra-performance liquid chromatography on a hydrophilic interaction chromatography column with tandem mass-selective detection (UPLC-MS/MS) to determine meldonium in human plasma was developed. The calibration curve acquired in the range of 10-6000 ng/mL had quadratic form. Method validation proved the conformity of its properties (selectivity, matrix effect, lower limit of quantification, accuracy, precision and recovery) with the established requirements. The stability tests necessary for bioanalytical studies were performed. For the first time, the method was successfully applied to the bioequivalence studies of generic and brand name oral drugs of meldonium in capsules. Based on data from 24 volunteers, it was determined that the mean pharmacokinetic curves of the drugs are characterized by a double peak profile. 相似文献
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Dr. Oleg G. Salnikov Alexandra Svyatova Dr. Larisa M. Kovtunova Dr. Nikita V. Chukanov Prof. Valerii I. Bukhtiyarov Dr. Kirill V. Kovtunov Prof. Eduard Y. Chekmenev Prof. Igor V. Koptyug 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(4):1316-1322
Magnetic resonance imaging (MRI) with the use of hyperpolarized gases as contrast agents provides valuable information on lungs structure and function. While the technology of 129Xe hyperpolarization for clinical MRI research is well developed, it requires the expensive equipment for production and detection of hyperpolarized 129Xe. Herein we present the 1H hyperpolarization of diethyl ether vapor that can be imaged on any clinical MRI scanner. 1H nuclear spin polarization of up to 1.3 % was achieved using heterogeneous hydrogenation of ethyl vinyl ether with parahydrogen over Rh/TiO2 catalyst. Liquefaction of diethyl ether vapor proceeds with partial preservation of hyperpolarization and prolongs its lifetime by ≈10 times. The proof-of-principle 2D 1H MRI of hyperpolarized diethyl ether was demonstrated with 0.1×1.1 mm2 spatial and 120 ms temporal resolution. The long history of use of diethyl ether for anesthesia is expected to facilitate the clinical translation of the presented approach. 相似文献
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