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1.
This paper discusses monitoring electromagnetic fields (natural and artificial) in the atmosphere. Methods are described for remote sensing of the atmosphere and surface in order to examine static and alternating electromagnetic-energy fluxes in the biosphere.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 69–79, December, 1991. 相似文献
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3.
I. V. Ukrainets E. V. Kolesnik L. V. Sidorenko O. V. Gorokhova A. V. Turov 《Chemistry of Heterocyclic Compounds》2007,43(3):326-333
A preparative method has been developed and the synthesis has been effected of anilides and heterylamides of 4-hydroxy-6-methyl-2-oxo-1-propyl-1,2,5,6,7,8-hexahydroquinoline-3-carboxylic
acid. A comparative analysis has been carried out of the structure and antitubercular properties of the synthesized compounds
and their analogs unsubstituted in the quinoline nucleus.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 405–414, March, 2007. 相似文献
4.
The composition of the various groups of liposoluble compounds in the leaves of wild cabbage of early-, middle-, and late-ripening varieties have been identified and their amounts have been determined by chromatographic and chemical methods. About 30 groups of lipid substances have been identified, among which free and esterified forms of sterols, di- and triacylglycerols, hydrocarbons, lipoquinones, mono- and digalactoside glycerides, cerebrosides, phosphatidylethanolamines, phosphatidylglycerols, and phosphatidylcholines predominate. The presence of 13 components has been established among the fatty acids, linolenic acid being present in the greatest amount (50%). The influence of the time of ripening of the cabbage variety (early-, middle-, or late-ripening) on the composition of the lipid complex has been elucidated.M. V. Lomonosov Technological Institute of the Food Industry, Odessa. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 180–185, March–April, 1989. 相似文献
5.
The reaction of dibenzylphosphine oxide with O-methyloximes of some ,-unsaturated ketones results in the phosphorylation at the -carbon atom to form methoxyiminophosphine oxides, whereas the reaction of dibenzylphosphine oxide with O-methyloximes of ,-unsaturated aldehydes affords aminodihydrophosphole oxides. 相似文献
6.
The qualitative and quantitative compositions of the grape and its component parts — flesh, skin, seeds — have been studied. Ten fractions have been identified, the main ones being cerebrosides and monogalactosyldiglycerides. The compositions of the fatty acids, of the sphingosine bases, of the sterols, and of the carbohydrates of the individual fraction of phytoglycolipids have been determined.Physicochemical Institute of the Academy of Sciences of the Ukrainian SSR, Odessa. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 296–300, May–June, 1984. 相似文献
7.
N A Tjukavkina S V Geodakyan A I Khvostova J A Kolesnik V I Glyzin 《Journal of chromatography. A》1991,571(1-2):312-317
The use of a small precolumn instead of an injection loop for the determination of a new phytochemical drug, fellavine, and its metabolites is described. The method combines the direct injection of plasma and urine into the reversed-phase precolumn with separation on a Spheri-5 RP-18 analytical column. Different sorbents in the precolumn were compared. A recovery of fellavine and its metabolites from biological fluids except rat plasma of almost 100% was achieved on Chrompack RP (30-40 microns) and LiChrosorb RP-18 (7 microns). For rat plasma only the last sorbent gave 80% fellavine recovery. The influence of the protein binding on the fellavine recovery was examined. The limit of detection was equal to 0.05 micrograms/ml fellavine for plasma and 0.02 micrograms/ml for urine. To enhance the limit of detection longer precolumns were perferred. 相似文献
8.
N. M. Shcheglova V. D. Kolesnik R. V. Ashirov 《Russian Journal of Organic Chemistry》2013,49(9):1329-1334
A convenient procedure has been proposed for the synthesis ortho-vinylbenzyl-substituted ethers, amines, and sulfides via reaction of o-(2-bromoethyl)benzyl bromide with various nucleophiles. 相似文献
9.
Rasika Prabhu Rasmus Klitkou Grigori A. Medvedev James M. Caruthers 《Journal of Polymer Science.Polymer Physics》2013,51(8):687-697
The linear viscoelastic behavior in dynamic shear and tensile creep at temperatures from −30 to 70 °C is measured for an styrene–butadiene rubber (SBR) elastomer cured with dicumyl peroxide to crosslinking densities between 0 and 23.5 × 10−5 mol/cm3. The G′, G″, and tan δ isotherms are analyzed by time–temperature superposition (TTS), where the tan δ master curves are consistent with those of Mancke and Ferry. However, to achieve the TTS in the lightly crosslinked SBR systems, an anomalous vertical shift is required in the narrow temperature region from 10 to 30 °C. The vertical shift factor in this temperature region is not the standard from rubber elasticity. No anomalous behavior is detected in the equilibrium modulus, which is a linear function of temperature in accordance with the classical theory of rubber elasticity. In contrast to SBR, standard vertical shifts are required to effect TTS for uncrosslinked polybutadiene and an ethylene propylene diene monomer elastomer. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013 相似文献
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