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41.
The results of an experimental investigation of the effect on heat transfer of the shape of the blunt leading edges of a delta wing are presented for a Mach number M=5 and angles of attack =10 and 15. The shape of the bluntness is observed to have a strong influence on the heat transfer to the edges and upper surface of the wing.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 180–183, September–October, 1990.  相似文献   
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The large statistical sum of a noninteracting nonrelativistic electron gas in constant parallel electric and magnetic fields is calculated.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 64–67, September, 1979.  相似文献   
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Growing market demand for portable energy storage has triggered significant research on high‐capacity lithium‐ion (Li‐ion) battery anodes. Various elements have been utilized in innovative structures to enable these anodes, which can potentially increase the energy density and decrease the cost of Li‐ion batteries. In this review, electrode and material parameters are considered in anode fabrication. The periodic table is then used to explore how the choice of anode material affects rate performance, cycle stability, Li‐ion insertion/extraction potentials, voltage hysteresis, volumetric and specific capacities, and other critical parameters. Silicon (Si), germanium (Ge), and tin (Sn) anodes receive more attention in literature and in this review, but other elements, such as antimony (Sb), lead (Pb), magnesium (Mg), aluminum (Al), gallium (Ga), phosphorus (P), arsenic (As), bismuth (Bi), and zinc (Zn) are also discussed. Among conversion anodes focus is placed on oxides, nitrides, phosphides, and hydrides. Nanostructured carbon (C) receives separate consideration. Issues in high‐ capacity research, such as volume change, insufficient coulombic efficiency, and solid electrolyte interphase (SEI) layer stability are elucidated. Finally, advanced carbon composites utilizing carbon nanotubes (CNT), graphene, and size preserving external shells are discussed, including high mass loading (thick) electrodes and electrodes capable of providing load‐bearing properties.  相似文献   
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The reaction of carbon monoxide with the surface of Ni, Pd, and Ni-Pd catalysts, deposited on -Al2O3, was investigated at 25°C by IR spectroscopy in conjunction with an adsorption volumetric technique. The IR spectra contained the following absorption bands (v, cm–1): 2020–2100 (AB1) (linear and subcarbonyl forms of adsorbed CO); 1945–1985 (AB2) (bridging); 1920–1940 (AB3) with a shoulder at 1870–1885 (AB4) (bridging and many-center). In the spectrum of Ni the absorption band AB5 appears at 1770–1780 (CO-Ni+). It appears with surface coverage a 1.3 mole CO/mole M. The optical density (A) of AB1 for Ni97Pd3 is appreciably higher than for the other investigated samples. In the Ni-Pd catalysts the intensity of AB2 in relation to AB1 is higher than in nickel. The introduction of K+ ions into the support of the bimetallic sample reduces the optical density of AB1. In modified Ni-Pd-K the AB3 and AB4 bands disappear.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1276–1282, June, 1992.  相似文献   
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Conclusions It can be concluded from this review that ferroelectric physics is one of the actively expanding branches of solid-state physics. The concepts of states related to the ferroelectric one, e.g., the ferroelastic state, have broadened significantly. Within this field successful studies are being performed of such general questions as phase transitions, subsystem interactions, i.e., the interaction of different quasiparticles, and other nonlinear processes. In ferroelectric semiconductors the interaction of charge carriers with spontaneous polarization is being studied, while in Seignette ferromagnetics the interaction of magnetic and electric subsystems is under investigation. Nonlinear phenomena are given special study in the phase transition region.A number of new interesting phenomena have been discovered in ferroelectric studies recently: phonon echo, photovoltaic effect, autolocalization of charge carriers in the phase transition region, etc. Many new classes of ferroelectrics have been discovered, thus demonstrating the broad extent of the ferroelectric state in nature. Apparently, certain organic compounds and liquid crystals may be classified as ferroelectrics. Results of ferroelectric studies are widely used in the national economy.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 5–39, January, 1979.  相似文献   
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Electrochemically controlled molecular recognition of a synthetic heparin mimetic, Arixtra, at nitrobenzene/water microinterfaces was investigated to obtain a greater understanding of interfacial recognition and sensing of heparin and its analogues with biomedical importance. In contrast to unfractionated heparin, this synthetic pentasaccharide that mimics the unique Antithrombin III binding domain of heparin possesses well-defined structure and ionic charge to enable quantitative interpretation of cyclic voltammetric/chronoamperometric responses based on the interfacial recognition at micropipet electrodes. Arixtra is electrochemically extracted from the water phase into the bulk nitrobenzene phase containing highly lipophilic ionophores, methyltridodecylammonium or dimethyldioctadecylammonium. Numerical analysis of the kinetically controlled cyclic voltammograms demonstrates for the first time that formal potentials and standard rate constants of polyion transfer at liquid/liquid interfaces are ionophore dependent. Moreover, octadecylammonium and octadecylguanidinium are introduced as new, simple ionophores to model recognition sites of heparin-binding proteins at liquid/liquid interfaces. In comparison to octadecyltrimethylammonium, the best ionophore for heparin recognition at liquid/liquid interfaces reported so far, these new ionophores dramatically facilitate Arixtra adsorption at the interfaces. With a saline solution at physiological pH, an Arixtra molecule is selectively and cooperatively bound to 5 molecules of the guanidinium ionophore, suggesting hydrogen-bond-directed interactions of each guanidinium with a few of 10 negatively charged sulfo or carboxyl groups of Arixtra at the interfaces.  相似文献   
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