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1.
Simultaneous thermogravimetry–differential thermal analysis (TG–DTA) and gas and liquid chromatography with mass spectrometry detection have been used to study the kinetics and decomposition of 2-hydroxybenzoic acid, 2-carboxyphenyl ester, commercially known as salsalate. Samples of salsalate were heated in the TG–DTA apparatus in an inert atmosphere (100 ml min−1 nitrogen) in the temperature range 30–500 °C. The data indicated that the decomposition of salsalate is a two-stage process. The first decomposition stage (150–250 °C) had a best fit with second-order kinetics with Ea=191–198 kJ/mol. The second decomposition stage (300–400 °C) is described as a zero-order process with Ea=72–80 kJ/mol. The products of the decomposition were investigated in two ways:
- (a)Salsalate was heated in a gas chromatograph at various isothermal temperatures in the range 150–280 °C, and the exit gas stream analyzed by mass spectrometry (GC–MS). This approach suggested that salsalate decomposes with the formation of salicylic acid, phenol, phenyl salicylate, and cyclic oligomers of salicylic acid di- and tri-salicylides.
- (b)One gram samples of salsalate were heated in a vessel under nitrogen to 150 °C, and the residues were analyzed by liquid chromatography–mass spectrometry (LC–MS). The major compound detected was a linear tetrameric salicylate ester.
2.
Y. M. Shulga A. A. Startsev Y. I. Yermakov B. N. Kuznetsov Y. G. Borod'ko 《Reaction Kinetics and Catalysis Letters》1977,6(3):377-383
By the XPS method it has been shown that in the catalysts obtained by interacting W(-C4H7)4 with SiO2 several oxidation states of the supported tungsten are realized together with a higher coverage of the silica surface with tungsten compounds, as compared with the catalysts prepared by impregnation of SiO2 with an aqueous solution of (NH4)2 WO4.
, , W(-C4H7)4 SiO2, , , SiO2 (NH4)2 WO4.相似文献
3.
V. I. Shulga 《辐射效应与固体损伤》2013,168(1-4):65-83
Sputtering of Cu single-crystal and polycrystal targets by 27 keV Ar ions has been simulated using the new binary collision cascade computer program OKSANA. The sputtering yield, the sputtering and reflection efficiencies, and the absolute and relative contributions to sputtering from various components have been calculated in a broad range of incidence angles. The obtained angular dependences of the sputtering yield have proved to agree with experimental data. Some features of sputtering due to semichannel focusing of incident particles have been found. The contributions to sputtering from several types of linear collision chains and from the primary knock-on atoms are considered in most detail. It has been shown, in particular, that the pure focused, pure defocused, and mixed focused-defocused collision chains contribute noticeably to sputtering. The contribution from the primary knock-on atoms is angle-dependent and reaches its maximum in the range of glancing angles for both single-crystal and polycrystal targets. 相似文献
4.
X-ray powder diffraction, scanning electron microscopy, infrared spectroscopy, and elemental analysis were used to study the interaction of titanium powder with finely powdered boron of particle size 10?C20 ??m in Na2B4O7 ionic melt, in the temperature range 973?C1088 K, at the 5?C10 h contact duration. The TiB2 formation was shown to occur at the temperatures 1018 K or above, that is, at the borax melting temperature. According to the scanning electron microscopy, theTiB2 powder consists of the 70?C75 nm particles, and its coherent scattering region calculated from the XRD data amounts to 55 nm. 相似文献
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8.
Kiryukhin D. P. Kichigina G. A. Kushch P. P. Vasilets V. N. Kabachkov E. N. Shulga Yu. M. 《High Energy Chemistry》2022,56(3):184-189
High Energy Chemistry - The influence of monomer concentration on the properties of radiation-synthesized tetrafluoroethylene telomers in perfluoro-1,3-dimethylcyclohexane has been studied by... 相似文献
9.
Pisarev Sergey A. Shulga Dmitry A. Palyulin Vladimir A. Zefirov Nikolay S. 《Structural chemistry》2019,30(2):509-522
Structural Chemistry - Investigations on the relative energy of two least-strain conformers for bicyclo[3.3.1]nonane 1, bicyclo[3.3.1]nonan-9-one 2, and their heteroanalogues:... 相似文献
10.
K. Dzilinski G. N. Synyakov A. M. Shulga I. V. Filatov G. P. Gurinovich 《Radiation Physics and Chemistry》1995,45(6):923-928
Radical anions of Zn-chlorin, Zn-octaethylchlorin complexes and their 15N and deuterium substituted analogues have been studied by EPR spectroscopy and the INDO molecular orbital method in the unrestricted Hartree-Fock procedure. Parameters of experimental spectra, determined by using the iterative least-squares fitting method, have been compared with those calculated on the basis of spin density distribution. A satisfactory agreement between the experimental hyperfine coupling constants and theoretical ones for the systems studied has been obtained. 相似文献