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991.
E. E. Nifant’ev D. A. Predvoditelev M. A. Malenkovskaya O. V. V’yunskovskaya 《Russian Journal of General Chemistry》2011,81(8):1592-1595
The synthesis of dithionophosphohomocholines was carried out by alkylation of trimethylamine with phosphorinane trimethylene
derivatives of tripentaerithritols. As a source tripentaerithritol acetals besides the compounds of symmetric structure were
used their stereoisomers. 相似文献
992.
Various methods are studied for preparing stable gas mixtures with trace amounts of volatile substances based on a buffer
effect of heterogeneous systems and implemented into headspace analysis, that is, static and dynamic versions of gas extraction.
Information is provided on certified procedures for preparing such mixtures, that is, vapor-phase sources of gas mixtures
included into the State Register of Measuring Instruments. 相似文献
993.
A method to solve boundary-value problems of magnetoelasticity for ring plates of variable stiffness is proposed. It is based
on a geometrically nonlinear theory of the second order and employs, in a successive manner, the Newmark scheme, the quasi-linearization
method, the method of lines, and the discrete-orthogonalization method 相似文献
994.
A. B. Shishmakov Yu. V. Mikushina O. V. Koryakova M. S. Valova S. Yu. Men’shikov L. A. Petrov 《Russian Journal of Applied Chemistry》2011,84(9):1555-1559
Fundamental aspects of the synthesis of 2,3,5-trimethylbenzoquinone by oxidation of 2,3,6-trimethylphenol adsorbed on the
surface of a titanium dioxide xerogel and on TiO2 modified with powdered cellulose with hydrogen peroxide without any organic solvent involved in the process were studied. 相似文献
995.
Fundamental aspects of phosphorite powder decomposition by citric acid were studied. 相似文献
996.
997.
Complexation of antibiotics cefazolin and cefoperazone with the methylene blue thiazine dye was studied. Composition (1: 1),
stability constants (150±30 M
−1), and solubility of the complexes were determined. 相似文献
998.
A. G. Smol’nikov V. V. Ogloblichev S. V. Verkhovskii K. N. Mikhalev A. Yu. Yakubovskii K. Kumagai Y. Furukawa A. F. Sadykov Yu. V. Piskunov A. P. Gerashchenko S. N. Barilo S. V. Shiryaev 《JETP Letters》2015,102(10):674-677
The magnetically ordered phase of the CuCrO2 single crystal has been studied by the nuclear magnetic resonance (NMR) method on 53Cr nuclei in the absence of an external magnetic field. The 53Cr NMR spectrum is observed in the frequency range νres = 61–66 MHz. The shape of the spectrum depends on the delay tdel between pulses in the pulse sequence τπ/2–t del–τπ–t del–echo. The spin–spin and spin–lattice relaxation times have been measured. Components of the electric field gradient, hyperfine fields, and the magnetic moment on chromium atoms have been estimated. 相似文献
999.
1000.