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81.
L. P. Vecherko A. F. Sviridov É. P. Zinkevich Leonid M. Kogan 《Chemistry of Natural Compounds》1976,11(3):379-384
Summary The structure of new triterpene glycosides from the roots of potmarigold calendula (C. officinalis) has been established: oleanolic acid 3-{[galactopyranosido-(13)] [glucopyranosido-(12)]--D-glucopy-ranoside} (calenduloside C) and the 28-acyl--D-glucopyranoside of calenduloside C (calenduloside D).All-Union Scientific-Research Institute of Medicinal Plants. N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 366–373, May–June, 1975. 相似文献
82.
The feasibility of adopting a new approach to the preparation of chiral carbocyclic compounds has been demonstrated by experiment. Synthesis was achieved by way of intramolecular free radical C
2
–C
6
cyclization of carbohydrate derivatives, which produced compounds with quaternary C
2
carbon atom having a strictly defined configuration.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117334 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 650–657, March, 1992. 相似文献
83.
o-Nitrophenol derivatives have been isolated from the culture liquid of the deuteromycetePyricularia oryzae Cav.: 4-hydroxy-3-nitrophenylacetic acid, 4-hydroxy-3-nitrobenzyl alcohol, 1- and 2-(4-hydroxy-3-nitrophenyl(ethanols, N-(4-hydroxy-3-nitrophenylethyl)acetamide, and pyriculamide. This is the first time that any of these compounds has been isolated from natural sources. The o-nitrophenols obtained possess moderate growth-inhibiting activity in relation to rice shoots. 相似文献
84.
A. V. Fokin A. Yu. Sizov V. L. Dyachenko V. D. Sviridov N. D. Chkanikov A. N. Nesmeyanov 《Russian Chemical Bulletin》1996,45(4):980-981
1,1-Dicyano-2,2-bis(triflüoronietliyl)etliylene alkylates phenoxazine and phenothiazine at 20 °C at thepara-position relative to the N atom.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 1026–1027, April, 1996. 相似文献
85.
Sviridov V. D. Chkanikov N. D. Korbukh I. A. Kolomiets A. F. Fokin A. V. 《Russian Chemical Bulletin》1989,38(7):1519-1522
1. | 4-Aminopyrimidines react with hexafluoroacetone to give pyrimidooxazines and pyrimidooxadiazines. |
2. | An account is given of the C5 aminoalkylation of 1,3-dimethyluracil by the trifluoroacetylimines of hexafluoroacetone and of the methyl ester of trifluoropyruvic acid. |
86.
S. I. Sviridov 《Chemistry of Natural Compounds》1992,27(4):410-413
A number of exometabolites have been isolated from the deuteromycetePyricularia oryzae Cav., of which harman and O-demethyldiaporthin have been isolated from this species for the first time. The latter is the first example of a hexaketide from fungi of the genusPyricularia, for which only penta- and heptaketides have previously been described.All-Union Scientific-Research Institute of Phytopathology, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 471–475, July–August, 1991. 相似文献
87.
T. V. Sviridova L. Yu. Sadovskaya A. I. Kokorin N. M. Lapchuk D. V. Sviridov 《Russian Journal of Physical Chemistry B, Focus on Physics》2016,10(4):561-565
Photoinduced processes in thin films of MoO3 and mixed V2O5: MoO3 oxides prepared by polycondensation of the respective oxoacids under solvothermal conditions are studied using Raman spectroscopy, ESR, and AFM. It is shown that, under UV irradiation, the photoinduced polycondensation occurs in the oxide films, leading to the formation of the oxygen bridges, an effect that opens up the possibility of developing a new photolithographic process. 相似文献
88.
I. I. Poddubnyi N. Yu. Pyatnitskaya N. G. Razuvanov V. G. Sviridov E. V. Sviridov A. Yu. Leshukov K. V. Aleskovskiy D. M. Obukhov 《Physics of Atomic Nuclei》2016,79(7):1170-1180
The effect discovered in studying a downward liquid-metal flow in vertical pipe and in a channel of rectangular cross section in, respectively, a transverse and a coplanar magnetic field is analyzed. In test blanket modules (TBM), which are prototypes of a blanket for a demonstration fusion reactor (DEMO) and which are intended for experimental investigations at the International Thermonuclear Experimental Reactor (ITER), liquid metals are assumed to fulfil simultaneously the functions of (i) a tritium breeder, (ii) a coolant, and (iii) neutron moderator and multiplier. This approach to testing experimentally design solutions is motivated by plans to employ, in the majority of the currently developed DEMO blanket projects, liquid metals pumped through pipes and/or rectangular channels in a transvers magnetic field. At the present time, experiments that would directly simulate liquid-metal flows under conditions of ITER TBM and/or DEMO blanket operation (irradiation with thermonuclear neutrons, a cyclic temperature regime, and a magnetic-field strength of about 4 to 10 T) are not implementable for want of equipment that could reproduce simultaneously the aforementioned effects exerted by thermonuclear plasmas. This is the reason why use is made of an iterative approach to experimentally estimating the performance of design solutions for liquid-metal channels via simulating one or simultaneously two of the aforementioned factors. Therefore, the investigations reported in the present article are of considerable topical interest. The respective experiments were performed on the basis of the mercury magneto hydrodynamic (MHD) loop that is included in the structure of the MPEI—JIHT MHD experimental facility. Temperature fields were measured under conditions of two- and one-sided heating, and data on averaged-temperature fields, distributions of the wall temperature, and statistical fluctuation features were obtained. A substantial effect of counter thermo gravitational convection (TGC) on averaged and fluctuating quantities were found. The development of TGC in the presence of a magnetic field leads to the appearance of low-frequency fluctuations whose anomalously high intensity exceeds severalfold the level of turbulence fluctuations. This effect manifest itself over a broad region of regime parameters. It was confirmed that low-energy fluctuations penetrate readily through the wall; therefore, it is necessary to study this effect further—in particular, from the point of view of the fatigue strength of the walls of liquid-metal channels. 相似文献
89.
V. V. Ammosov D. S. Baranov A. P. Bugorski A. A. Ivanilov P. V. Ivanov V. I. Konyushko V. M. Korabliev V. A. Korotkov V. I. Kotchetkov V. I. Kurbakov V. V. Makeev A. I. Mukhin A. G. Myagkov A. Yu. Polyarush Yu. M. Sviridov A. A. Sokolov E. P. Kuznetsov H. -J. Grabosch H. H. Kaufmann U. Krecker R. Nahnhauer S. Nowak S. Schlenstedt H. Vogt SKAT-Collaboration 《Zeitschrift fur Physik C Particles and Fields》1986,30(2):175-182
Neutrino and antineutrino charged current reactions are studied inclusively at energies below 30 GeV using the freon filled bubble chamber SKAT at the Serpukhov accelerator. Data are given for the nucleon structure functions and the differential spectradσ/dy. The results are compared with predictions of the Quark-Parton Model and Quantum Chromodynamics. 相似文献
90.