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11.
12.
A. S. Ivanova M. V. Mikhan' G. M. Alikina G. S. Litvak E. M. Moroz E. B. Burgina 《Kinetics and Catalysis》2000,41(6):816-825
The possibility for the formation of garnet structures in the Mn–Fe–Zr–O and Ca–Sm–Zr–O systems obtained by the precipitation of the corresponding salts is studied. It is shown that, in the Mn–Fe–Zr–O system, garnet is crystallized at 860–920°C, for which probable cation distribution is estimated to be {Zr2.5
4+Mn0.5
2+}[Mn2
2+](Fe2.5
3+Mn0.5
3+)O12. In the Ca–Sm–Zr–O system, the perovskite CaZrO3, pyrochlore Sm2Zr2O7, and CaO are formed at 900–1200°C, but compounds with garnet structures are not found. The reported systems are characterized by surface areas of 300–450 m2/g at 450°C, and they have the polydisperse distribution of pores over sizes. The introduction of surfactants at the stage of component mixing enables an increase in the overall pore volume and mechanical strength of these systems. The Mn–Fe–Zr and Ca–Sm–Zr compositions are active catalysts for the complete oxidation of hydrocarbons. 相似文献
13.
G. I. Panov G. K. Boreskov A. S. Kharitonov E. M. Moroz 《Reaction Kinetics and Catalysis Letters》1981,16(2-3):247-251
The activity of barium nitride in the isotope exchange of nitrogen is 2–3 orders of magnitude higher than that of Fe and Ru. In the temperature range from 373 to 673 K the activation energy of exchange is 40 kJ/mol.
2–3 Fe Ru. 373–673 40 /.相似文献
14.
15.
Okunev A. G. Sharonov V. E. Gubar" A. V. Danilova I. G. Paukshtis E. A. Moroz E. M. Kriger T. A. Malakhov V. V. Aristov Yu. I. 《Russian Chemical Bulletin》2003,52(2):359-363
Sorption of CO2 in the presence of water vapor by the K2CO3—-Al2O3 composite sorbent was studied by IR spectroscopy in situ, X-ray diffraction analysis, and the differentiating dissolution method and reasons for a decrease in its dynamic capacity are given. The samples containing K2CO3·1.5H2O in pores are characterized by the maximal dynamic capacity. A mechanism for CO2 sorption was proposed, which qualitatively explains the obtained dependence of the capacity on the water content in the composite sorbent. A high dynamic capacity can be maintained by regeneration of the sorbents by water vapor at 170 °N. The capacity of the sorbents decreases during the first 10 sorption—regeneration cycles due to the formation of an inactive phase of potassium aluminum carbonate. 相似文献
16.
Tatiana Kuznetsova Vladislav Sadykov Lubsan Batuev Ella Moroz Elena Burgina Vladimir Rogov Vladimir Kriventsov Dmitrii Kochubey 《天然气化学杂志》2006,15(3):149-163
For dispersed ceria-zirconia-based solid solutions prepared via the polymerized complex method and annealed at 700℃, effects of bulk doping by Ca, Mn, Co, Bi or Nb cations and surface modification by Mn and Pt on their structural features, surface/bulk oxygen reactivity and catalytic activity in methane combustion are considered. With up to 20 mol% doping, a structural type of homogeneous solid solutions of anion-deficient fluorite with disordered anion vacancies is formed. Doping by transition metal cations or Pt increases the mobility and reactivity of the surface/bulk oxygen. A broad variation in specific rates of methane combustion for the studied systems was observed, suggesting structural sensitivity of this reaction. In general, there is no universal relationship between the oxygen mobility, the reactivity and the catalytic activity in methane combustion, which is explained by the factor of specific methane activation on surface active sites. For the Pt-promoted samples, Pt efficiency in methane activation depends on the Pt-support interaction, and the most favorable ones being mixed Pt/MnOx and Pt/NbOx clusters on the surface of the supports that exhibit high lattice oxygen mobilities. 相似文献
17.
E. M. Moroz W. A. Drozdov V. A. Ushakov A. K. Dzhunusov P. G. Tsyrulnikov 《Reaction Kinetics and Catalysis Letters》1990,41(1):109-114
X-ray diffraction studies of supported Ce/Al2O3 and Pt–Ce/Al2O3 catalysts have shown that besides a bulk phase CeO2 a product of the interaction with the support cerium aluminate having a perovskite structure, is usually formed. Platinum in unreduced modified samples forms an oxide and is statistically distributed in the perovskite phase of cerium aluminate. After reduction, only half of the metal is in the metallic state with a particle size of 10 Å.
, CeO2, - . . 10 Å.相似文献
18.
S. V. Gurevich P. A. Simonov A. S. Lisitsyn V. A. Likholobov E. M. Moroz A. L. Chuvilin V. N. Kolomiichuk 《Reaction Kinetics and Catalysis Letters》1990,41(1):211-216
Preoxidation of the surface of carbon support was found to increase the dispersity of palladium and activity of Pd/C catalysts obtained by reduction of supported Pd(OAc)2, in hydrogenation of olefins. Probable reasons for this effect are discussed.
, Pd/C , Pd(OAc), . .相似文献
19.
S. B. Halligudi M. M. Taqui Khan B. L. Moroz A. L. Chuvilin I. P. Prosvirin V. A. Likholobov 《Reaction Kinetics and Catalysis Letters》1991,44(1):139-146
Ru/SiO2 catalysts prepared by reduction of supported RuCl3·xH2O are active in gas-phase hydroformylation of propylene at low pressure (ca. 0.3 MPa) of H2+CO+C3H6 mixtured and show unexpectedly high selectivity towards unbranched oxo-products. Data concerning the effect of electronic state and dispersity of Ru on their catalytic behavior have been obtained.
Ru/SiO2, RuCl3·xH2O, (0,3 ) - . .相似文献
20.
The spatial arrangement of active component (Pt) particles on the surface of a support (Sibunit globule) has been studied by bright-field electron tomography. A tomographic attachment for a standard specimen holder and tomographic grids have been designed. The tomographic procedure has been refined, and adequate tilt series alignment and tomographic reconstruction algorithms have been chosen. The 3D distribution of the active component in the catalyst grain has been studied: particles hidden in micropores have been directly observed, and the size of the pores connecting internal cavities with the exterior has been estimated. 相似文献