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51.
Christian Maes 《Journal of statistical physics》1990,61(3-4):667-681
An anisotropic lattice gas dynamics is investigated for which particles on
d
jump to empty nearest neighbor sites with (fast) rate –2 in a specified direction and some particular configuration-dependent rates in the other directions. The model is translation and reflection invariant and is particle conserving. The space coordinate in the fast-rate direction is rescaled by –1. It follows that the density field converges in probability, as 0, to the corresponding solution of a nonlinear diffusion-type equation. The microscopic fluctuations about the deterministic macroscopic evolution are determined explicitly and it is found that the stationary fluctuations decay via a power law (1/r
d
) with the direction dependence of a quadrupole field. 相似文献
52.
J. A. M. Janssen 《Journal of statistical physics》1989,57(1-2):187-198
The master equation for a complex chemical reaction cannot always be reduced to a simpler master equation, even if there are fast and slow individual reaction steps. Nevertheless the elimination of intermediates can be carried out with the help of the-expansion. This is illustrated with a well-known complex reaction: the dissociation of N2O5. It is shown that the intrinsic fluctuations in the N2O5 decay are larger than those implied by the master equation suggested by the macroscopic rate law. 相似文献
53.
本文研究了18种α-氨基酸的快原子轰击质谱,发现添加三氟乙酸溶液能显著提高灵敏度,改善谱图。特征碎片主要有中性丢失CO2H2,H2O,NH3的离子以及R^+离子。侧链的性质决定了碎片的产生和离子的强弱。 相似文献
54.
本文拟定了一个催化荧光法测定痕量铜的新方法,确定了该催化反应的速度方程式和反应级数。方法检测限达0.1ng Cu/ml,相对标准偏差为3.7%,具有较好的选择性,可不经分离直接用于头发样品中铜的测定,回收及对照实验结果令人满意。 相似文献
55.
Sadahito Aoshima Tomohide Yoshida Arihiro Kanazawa Shokyoku Kanaoka 《Journal of polymer science. Part A, Polymer chemistry》2007,45(10):1801-1813
Our recent extensive research on Lewis acid catalysts with a weak base for the cationic polymerization of vinyl ethers led to unprecedented living reaction systems: fast living polymerization within 1–3 s; a wide choice of metal halides containing Al, Sn, Fe, Ti, Zr, Hf, Zn, Ga, In, Si, Ge, and Bi; and heterogeneously catalyzed living polymerization with Fe2O3. The use of added bases for the stabilization of the propagating carbocation and the appropriate selection of Lewis acid catalysts were crucial to the success of such new types of living polymerizations. In addition, the base‐stabilized living polymerization allowed the quantitative synthesis of star‐shaped polymers with a narrow molecular weight distribution via polymer‐linking reactions and the precision synthesis and self‐assembly of stimuli‐responsive block copolymers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1801–1813, 2007. 相似文献
56.
57.
Jia-you Shu Mo Zhu Yi Shu Qi-jun Liu Tong Li 《高分子科学》2006,(4):395-401
The new chelate resins, abbreviated as PNBMZs and PBBMZs based on epoxide polymer, were synthesized by polycondensation of N,N-diglycidyl-4-glycidyloxyaniline or 1,4-bis(2,3-epoxypropyl)benzene with the primary amine group of 1,3-bis(benzimidazol-2yl)propylamine (BBPAH). The ion exchangers contain 2.71-3.23 mmol of the ligand contents per gram of the resin. Batch extraction capacities were determined for the metal chloride salts in buffer solutions in the pH range from -1 to 6.0. The chelate resins were very selective for Cu^2+, Zn^2+, Cd^2+ in the presence of other divalent transition metal ions. The maximum uptake capacities of PNBMZ (synthetic molar ratio = 1:1.5) under non-competitive condition were found to be 0.94 mmol/g for Cu^2+ at pH = 2, 1.3 mmol/g for Cd^2+ at pH = 1 and 1.75 mmol/g for Zn^2+ at pH = -1 respectively. While in the case of PBBMZ, it was 1.39 mmol/g for Cd〉 at pH = 1. The metal-uptake behaviors for both of them showed strong pH dependence, and their extraction capacities increase with decreasing pH. The uptake of Cu^2+ by the resin PNBMZs at pH = 1 was found to be rather fast with t1/2 = 18 min. Metal-uptake experiments under competitive conditions also confirm that the chelate resins have a high selectivity for Cu^2+, Zn^2+, Cd^2+ and the contrary pH dependence. 相似文献
58.
59.
Novel Fast Ion Conductors of the Type M MIIICl6 (MI = Li, Na, Ag; MIII = In, Y) The ternary chlorides Li3InCl6, Na3InCl6, Ag3InCl6, and Li3YCl6 have been studied by difference scanning calorimetry, high-temperature X-ray, infrared, and high-temperature Raman methods. Impedance spectroscopic measurements exhibit fast ionic conductivity increasing in the sequence Na3InCl6 < Li3YCl6 < Ag3InCl6 < Li3InCl6. In the range of 300°C, Li3InCl6 is the best lithium ion conductor known so far (σ = 0,2 Ω?1 cm?1 at 300°C). With the exception of Na3InCl6, the chlorides exhibit complicated order-disorder phase transitions. 相似文献
60.
In solid-state NMR, deuteron (2H) spectroscopy can be performed in full analogy to1H spectroscopy, including2H chemical-shift resolution and2H-X dipolar correlation schemes, when the NMR experiments are conducted in a “rotor-synchronized” fashion under fast magic-angle
spinning. Here, 2H-X NMR experiments of this type, including2H-15N and2H-1H chemical-shift correlations and distance measurements, are introduced and demonstrated on cytosine monohydrate, whose acidic
protons can readily be replaced by deuterons by recrystallization from D2O. In this way,2H NMR spectroscopy provides information complementary to1H NMR data, which is particularly useful for studying hydrogen bonds in supra- or biomolecular systems.
Electronic supplementary material Supplementary material is available in the online versionof this article atand is accessible for authorized users. 相似文献