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111.
I. B. Krynetskii A. Krapf V. P. Martovitskii N. P. Shabanova S. Yu. Gavrilkin V. I. Kovalenko A. P. Rusakov A. I. Golovashkin 《Bulletin of the Lebedev Physics Institute》2011,38(12):349-353
The thermal expansion of single crystals of the Bi2Sr2−x
La
x
CuO6+δ
high-temperature superconducting (HTSC) system in the insulating phase with compositions having no superconducting transition
to a temperature of 1.8 K (x ≥ 0.8) is measured in an arbitrary direction in the (ab) plane in the temperature range of 7–50 K. Temperature regions of material compression upon heating are found. The study
of anomalies in magnetic fields of 3 and 6 T, parallel and perpendicular to the c-axis revealed an anisotropic and nonmonotonic effect of the field on thermal expansion. Such anomalies for the n-type Nd2−x
Ce
x
CuO4−δ
HTSC sample also having no superconducting transition are detected for the first time. The results show that the anomaly
nature is caused by anisotropic electronic ordering, probably, by the charge density wave in the CuO2 plane and superconductivity fluctuations in the insulating phase. 相似文献
112.
O. I. Solov’ev D. A. Rusakov A. A. Filaretov L. N. Komissarova 《Russian Journal of Inorganic Chemistry》2013,58(2):209-212
Subsolidus phase formation in the Ag3VO4-ScVO4 quasi-binary system was studied using X-ray powder diffraction and DTA in air under atmospheric pressure over the entire range of component concentrations in 5 mol % steps between 20 and 800°C. Two compounds were found to form: Ag3Sc(VO4)2 and Ag3Sc2(VO4)3, both melting incongruently at 750 ± 5 and 960 ± 5°C, respectively. A T-x diagram of the Ag3VO4-ScVO4 quasi-binary system was constructed. A eutectic (T m = 450 ± 5°C) is between the compounds Ag3VO4 and Ag3Sc(VO4)2; Ag3VO4 concentration is ~5 mol %. 相似文献
113.
Chistyakova N. I. Rusakov V. S. Zavarzina D. G. Slobodkin A. I. Gorohova T. V. 《Hyperfine Interactions》2004,156(1-4):411-415
Hyperfine Interactions - Mössbauer investigations of the influence of physicochemical factors and the inert organic substances on the magnetite formation by thermophilic dissimilatory... 相似文献
114.
V. M. Paskonov T. P. Petukhova S. V. Rusakov 《Computational Mathematics and Modeling》1990,1(1):107-117
An implicit iterative difference scheme of second-order accuracy in space and in time is proposed for numerical solution of nonstationary Navier—Stokes equations. The scheme has been applied to model a nonstationary axisymmetric flow in the near wake produced by injection through an annular nozzle from the tail of a supersonic body.Translated from Vychislitel'naya Matematika i Matematicheskoe Obespechenie EVM, pp. 216–231, 1985. 相似文献
115.
First example of the correlated calculation of the one‐bond tellurium–carbon spin–spin coupling constants: Relativistic effects,vibrational corrections,and solvent effects
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Irina L. Rusakova Yury Yu. Rusakov Leonid B. Krivdin 《Journal of computational chemistry》2016,37(15):1367-1372
This work reports on the comprehensive calculation of the NMR one‐bond spin–spin coupling constants (SSCCs) involving carbon and tellurium, 1J(125Te,13C), in four representative compounds: Te(CH3)2, Te(CF3)2, Te(C?CH)2, and tellurophene. A high‐level computational treatment of 1J(125Te,13C) included calculations at the SOPPA level taking into account relativistic effects evaluated at the 4‐component RPA and DFT levels of theory, vibrational corrections, and solvent effects. The consistency of different computational approaches including the level of theory of the geometry optimization of tellurium‐containing compounds, basis sets, and methods used for obtainig spin–spin coupling values have also been discussed in view of reproducing the experimental values of the tellurium–carbon SSCCs. Relativistic corrections were found to play a major role in the calculation of 1J(125Te,13C) reaching as much as almost 50% of the total value of 1J(125Te,13C) while relativistic geometrical effects are of minor importance. The vibrational and solvent corrections account for accordingly about 3–6% and 0–4% of the total value. It is shown that taking into account relativistic corrections, vibrational corrections and solvent effects at the DFT level essentially improves the agreement of the non‐relativistic theoretical SOPPA results with experiment. © 2016 Wiley Periodicals, Inc. 相似文献
116.
E. D. Politova S. A. Ivanov G. M. Kaleva A. V. Mosunov V. S. Rusakov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(10):1640-1649
The paper presents a review of works on the synthesis, structural composition effects, phase transitions, and electrical conductivity properties of multicomponent solid solutions based on heterosubstituted lanthanum gallate (La,A)(Ga,M)O3 ? y . High-temperature phase transitions and structural and charge ordering effects were studied. The presence of iron cations in different valence states was proved; the relative contents of these cations depended on the x parameter and nonstoichiometry parameter y of the base composition. For M = Fe, antiferromagnetic ordering was observed; its temperature interval was determined by the concentration of iron cations in the high-spin state. The total conductivity was found to increase as the concentration of transition metal cations grew because of an increase in the electronic conductivity component. The data on structural parameters and dc and ac conductivity substantiated the conclusion that the highest ionic conductivity and permeability to oxygen were characteristic of iron-containing oxides. The results obtained are evidence that crystal chemical factors play a determining role in the formation of the ion-conducting properties of anion-deficient perovskite-like oxides. 相似文献
117.
Yu. Yu. Rusakov L. B. Krivdin N. V. Istomina V. A. Potapov S. V. Amosova 《Russian Journal of Organic Chemistry》2008,44(10):1418-1421
Theoretical conformational analysis of divinyl selenide was performed in terms of the Møller-Plesset second-order perturbation theory (MP2/6-311G**). Angular distribution of the probability density of populations of its rotational conformers was determined by analysis of the rotational potential energy surface. Divinyl sulfide was found to exist as an equilibrium mixture of three conformers having essentially nonplanar structure; the major conformer is syn-s-cis-s-trans, and the two others are syn- and anti-s-trans-s-trans with higher energy. 相似文献
118.
V. S. Pokatilov V. S. Rusakov A. O. Makarova V. V. Pokatilov M. E. Matsnev 《Physics of the Solid State》2016,58(2):315-318
Single-phase polycrystalline La0.75Sr0.25Co0.9857Fe0.02O3 samples have been prepared by solidstate ceramic technology. The samples have the rhombohedral structure (space group \(R\bar 3c\)). The studies of perovskite La0.75Sr0.25Co0.9857Fe0.02O3 by Mössbauer spectroscopy on impurity 57Fe nuclei in the temperature range of 5–293 K have revealed the existence of a superparamagnetic relaxation in the temperature range of 100–210 K. The parameters of hyperfine interactions (hyperfine magnetic fields, line shifts, and quadrupole shifts) and the anisotropy energy have been measured, and the frequencies of magnetic moment relaxation of iron ions have been estimated. 相似文献
119.
D. A. Rusakov A. A. Filaretov A. P. Bobylev V. P. Danilov L. N. Komissarova 《Russian Journal of Inorganic Chemistry》2007,52(12):1844-1854
Indium strontium hydrogen nitrate SrIn2[PO3(OH)]4 was synthesized under mild hydrothermal conditions (T = 180 or 200°C) and characterized using IR spectroscopy, chemical analysis, and thermal analysis. A structure model obtained ab initio was refined by the Rietveld method: a= 9.6412(1) Å, b = 13.763(1) Å, c = 9.3579(1) Å, R obs = 0.0183, R p = 0.0493 (space group B2212, Z = 4). The acentricity of the structure was confirmed by SHG tests (I 2ω/I 2ω(SiO2) ≈ 2.0). In the SrIn2[PO3(OH)]4 structure, indium atoms reside in distorted InO6 octahedra and form, together with PO3(OH) tetrahedra, a mixed 3D structure {In2[PO3(OH)]4} 3∞ 2? whose voids are occupied by Sr2+ cations (CN = 8). The block-dimer In2(HPO4)10 is the most informative unit of the framework. Blocks are condensed into infinite columns running in the [101] direction. The compound is thermally stable up to 400°C. 相似文献
120.
Dzhilavyan L. Z. Lapik A. M. Latysheva L. N. Nedorezov V. G. Ponomarev V. N. Rusakov A. V. Sobolevsky N. M. Solodukhov G. V. 《Physics of Atomic Nuclei》2021,84(9):1610-1619
Physics of Atomic Nuclei - In this article, we describe an experimental verification of the correctness of registration of delayed neutrons from 238U photofission at a maximum energy of 10 MeV of... 相似文献