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1.
Interatomic distances and distributions of rare-earth and strontium cations over two sites in the structure of (La1?x Hox)2SrAl2O7 solid solutions were determined by means of full-profile X-ray structural analysis. Introduction of holmium cations into the La2SrAl2O7 oxide results in ordered distribution of Ln3+ cations and stabilization of the perovskite-like structure. 相似文献
2.
E. A. Dikusar N. G. Kozlov V. I. Potkin T. D. Zvereva A. P. Yuvchenko M. P. Bei N. V. Kovganko 《Chemistry of Natural Compounds》2006,42(5):539-542
Previously unreported esters 1b–20b were synthesized from natural terpene alcohols, sterols, plant phenols, and camphar oxime (1a–20a) by reaction with o-carborane-C-carboxylic acid chloride.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 434–436, September–October, 2006. 相似文献
3.
O. S. Kukovinets T. I. Zvereva V. G. Kasradze F. Z. Galin L. L. Frolova A. V. Kuchin L. V. Spirikhin M. I. Abdullin 《Chemistry of Natural Compounds》2006,42(2):216-218
An effective method was proposed for synthesizing (+)-cis-1R-acetoxymethyl-3-isopropenyl-2,2-dimethylcyclobutane, a pheromone of the citrus mealybug, based on ozonolysis of verbenone
that led in one step to the key synthon 1R,3S-3-acetyl-2,2-dimethylcyclobutanecarboxylic acid.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 179–180, March–April, 2006. 相似文献
4.
N. A. Maiorova E. K. Tuseeva V. E. Sosenkin A. Yu. Rychagov Yu. M. Vol’fkovich A. V. Krestinin G. I. Zvereva O. M. Zhigalina O. A. Khazova 《Russian Journal of Electrochemistry》2009,45(9):1089-1097
The structure and hydrophilic-hydrophobic properties of functionalized single-wall carbon nanotubes are studied by the standard
porosimetry method. It is shown that the functionalized nanotubes have highly hydrophilic surface; at that the summary surface
area measured “by octane” decreased, as a result of the functionalizing, due to the blocking of the nanotubes’ inner channels
by the functional groups located at the nanotubes’ ends. The nanotubes’ capacitive properties are studied; their charging-discharging
curves appeared being highly reversible, unlike those of other carbonaceous materials. Catalytic properties of the functionalized
nanotubes are studied, with particular tendency toward their using as a carrier of platinum catalysts for the methanol oxidation
and oxygen electroreduction reactions. When minor amounts (5–10 μg cm−2) of platinum or platinum-ruthenium alloy are deposited onto the nanotubes’ hydrophilic surface, uniform layer of the catalyst
is formed, with specific surface area up to 150–300 m2 g−1; high current of the methanol oxidation or oxygen electroreduction is observed at these catalysts. When the catalyst deposit
mass increased, its specific surface area decreased, as well as the specific current of the reactions occurring thereon. When
the current is related to the electrochemically active unit surface, the catalytic activity is nearly the same both for different
catalyst mass deposited onto the nanotubes and the same catalyst mass at different carbonaceous carriers. 相似文献
5.
The review discusses the published data on the concentrations of chemical elements in tissues of the cardiovascular system determined by atomic absorption and atomic emission spectrometry, mass spectrometry, and also X-ray fluorescence analysis, proton-induced X-ray emission, and X-ray microanalysis. The main parameters of X-ray spectrometry methods used for the examination of the cardiovascular system are compared, the new trends in the analysis of these samples and the main sample preparation approaches are considered. 相似文献
6.
N. A. Zhukovskaya E. A. Dikusar V. I. Potkin S. K. Petkevich T. D. Zvereva Yu. S. Zubenko D. A. Rudakov V. L. Shirokii 《Russian Journal of General Chemistry》2013,83(3):542-544
Oximes of β-isatin, isoxazole- and ferrocene-containing ketones, o- and m-carborane alcohols react with isoxazol- and isothiazolecarboxylic acid chlorides in the presence of triethylamine to afford the corresponding esters. 相似文献
7.
The results of environmental assessment of ash ponds of thermal power plants in Vladivostok and Khabarovsk are given. High radioactivity of coal in the Russian Far East is responsible for the accumulation of radionuclides in the fly and bottom ashes, which leads to pollution of atmosphere, lithosphere, biosphere, and hydrosphere with toxic and radioactive elements. Runoff carries these elements to the Ussuri Bay of the Sea of Japan. Harmful effect of these wastes on human health is noted, and possible ways of their utilization have been recommended. 相似文献
8.
E. A. Dikusar V. I. Potkin T. D. Zvereva N. A. Zhukovskaya S. K. Petkevich A. S. Pavlyuchenkova M. Yu. Murashova A. P. Polikarpov A. A. Shunkevich A. P. Yuvchenko R. M. Zolotar’ 《Russian Journal of Organic Chemistry》2013,49(2):221-227
By the condensation of substituted aldehydes of vanillin series with 1,3-propanediol in boiling benzene in the presence of sulfo cation exchanger FIBAN K-1 as catalyst functionally 2-R-substituted 1,3-dioxanes were synthesized. 相似文献
9.
G. N. Zvereva 《Optics and Spectroscopy》2003,94(2):191-198
The intensities of vacuum-ultraviolet emission of excimers in a krypton-xenon mixture are calculated in terms of the homogeneous model of a barrier discharge. The mechanisms of the formation of excimer molecules are investigated at different xenon concentrations. The obtained dependences of the efficiency of vacuum-ultraviolet emission on the reduced electric field E/N (where E is the electric field strength and N is the particle concentration of the gas) and the xenon content exhibit a plateau and a subsequent steep decline. The efficiency of vacuum-ultraviolet emission reaches a maximum at the plateau when the xenon content δ is approximately equal to 40%. The concentrations of xenon excimers can be as high as 1014–1015 cm?3. This is comparable to the concentrations in a barrier discharge in pure xenon. 相似文献
10.