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111.
针对大规模分布式系统中对象迁移、网络和系统动态重构的要求,本文提出了一种层次式的命名和编址方案,它将对位置透明的标识(OID)和表示位置的地址(OAD)二者结合起来标识对象. 相似文献
112.
IntroductionTheincreasingnecessity0fpharmacologicalresearchforchiraldrugshasrenderedchiralseparationanactiveareaincaPillaryelectroph0resis(CE)today.Variousmodes0fCE,includingcaPillaryzoneelectroph0resis(CZE),micellarelectrokineticchromatography(MEKC),caPillarygelelectrophoresis(CGE)andcapillaryisotachophoresis(CITP),havebeenappliedforthispurp0se',amongwhichCZEisthemostpopularoneforitshighefficiency,lowexpenseandeaseofoperation.Forsuccessfulchiralseparati0ninCZE,theselectortypeisofcr… 相似文献
113.
114.
We show that the dynamics of transmission control protocol (TCP) may often be chaotic via a quasiperiodic route consisting of more than two independent frequencies, by employing a commonly used ns-2 network simulator. To capture the essence of the additive increase and multiplicative decrease mechanism of TCP congestion control, and to qualitatively describe why and when chaos may occur in TCP dynamics, we develop a 1D discrete map. The relevance of these chaotic transport dynamics to real Internet connections is discussed. 相似文献
115.
116.
We present a detailed study of the transport and the efficiency of a ratchet system in a periodic potential in the presence of correlated noises. The current and the efficiency of the system are investigated. It is found that, when the potential is spatially symmetric, the correlation between the two noises can induce a net transport. The efficiency shows many interesting features as a function of the applied force, the noise intensity, the external load, etc. The efficiency can be maximized as a function of noise intensity (or temperature), which shows that the thermal fluctuation can facilitate the efficiency of energy transformation. 相似文献
117.
De-hua?Wen Wei?Chen Xian-ju?Wang Bao-quan?Ai Guo-tao?Liu Dong-qiao?Dong Liang-gang?LiuEmail author 《The European Physical Journal A - Hadrons and Nuclei》2004,21(2):349-354
The influence of rotation on the total masses and radii of neutron stars is calculated by Hartles slow-rotation formalism, while the equation of state is considered in a relativistic
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model. As the changes of the mass and radius of a real neutron star caused by rotation are very small in comparison with the total mass and radius, one can see that Hartles approximate method is rational to deal with the rotating neutron stars. If three property values, mass, radius and period, are observed for the same neutron star, then the EOS of this neutron star could be decided entirely.Received: 7 November 2003, Revised: 17 February 2004, Published online: 31 August 2004PACS:
04.40.Dg Relativistic stars: structure, stability, and oscillations - 95.30.Sf Relativity and gravitation - 97.10.Kc Stellar rotation - 97.60.Jd Neutron stars 相似文献
118.
Bao-Quan?Ai Xian-Ju?Wang Guo-Tao?Liu Hui-Zhang?Xie De-Hua?Wen Wei?Chen Liang-Gang?LiuEmail author 《The European Physical Journal B - Condensed Matter and Complex Systems》2004,37(4):523-526
We present a study of the transport of a Brownian particle moving in a periodic symmetric potential in the presence of asymmetric unbiased fluctuations. The particle is considered to move in a medium with periodic space dependent friction. By tuning the parameters of the system, the direction of the current exhibits reversals, both as a function of temperature as well as the amplitude of rocking force. We found that the mutual interplay between the opposite driving factors is the necessary term for current reversals.Received: 11 October 2003, Published online: 9 April 2004PACS:
05.40.-a Fluctuation phenomena, random processes, noise, and Brownian motion - 02.50.Ey Stochastic processes - 87.10. + e General theory and mathematical aspects 相似文献
119.
Yoshiaki Tanaka Tatsuo Fujii Yoshihiro Kusano Yasunori Ikeda 《Solid State Communications》2007,141(3):122-126
Single-phases of Pb-substituted Bi-Ca-Co-O misfit-layer cobaltites with various Pb concentrations have been synthesized and the Pb-substitution effects on the structural, electrical and magnetic properties have been systematically investigated. Powder X-ray diffraction analysis showed that the single-phases of Bi1.8−x/2PbxCa2Co2Oz were obtained up to x=0.6-0.7 under the optimized synthesis conditions. The lattice parameters of Bi1.8−x/2PbxCa2Co2Oz continuously changed with increasing Pb concentration. The electron diffraction analysis suggested that the structure consisted of two different sublattices with a rock salt structure (RS) and a hexagonal CdI2 structure (H), respectively, without modulation. In combined with the chemical composition analysis, the chemical formulas of the x=0 and x=0.6 samples were determined approximately as [Bi1.74Co0.31Ca2.01O4]RS[CoO2]1.69 and [Bi1.47Pb0.38Co0.29Ca1.98O4]RS[CoO2]1.71, respectively. The electrical resistivity became more metallic with increasing the Pb concentration up to x=0.6. Moreover, the Pb-substitution simultaneously increased the antiferromagnetic Weiss temperatures and decreased the effective magnetic moments of the Co ions. 相似文献
120.
Xiao‐Hua Ma Li‐Min Fu Yunfeng Zhao Xi‐Cheng Ai Jian‐Ping Zhang Yu Han Zhi‐Xin Guo 《Journal of Polymer Science.Polymer Physics》2011,49(9):649-656
Achiral nonlinear optical (NLO) chromophores 1,3‐diazaazulene derivatives, 2‐(4′‐aminophenyl)‐6‐nitro‐1,3‐diazaazulene (APNA) and 2‐(4′‐N,N‐diphenylaminophenyl)‐6‐nitro‐1,3‐diazaazulene (DPAPNA), were synthesized with high yield. Despite the moderate static first hyperpolarizabilities (β0) for both APNA [(136 ± 5) × 10?30 esu] and DPAPNA [(263 ± 20) × 10?30 esu], only APNA crystal shows a powder efficiency of second harmonic generation (SHG) of 23 times that of urea. It is shown that the APNA crystallization driven cooperatively by the strong H‐bonding network and the dipolar electrostatic interactions falls into the noncentrosymmetric P212121 space group, and that the helical supramolecular assembly is solely responsible for the efficient SHG response. To the contrary, the DPAPNA crystal with centrosymmetric P‐1 space group is packed with antiparalleling dimmers, and is therefore completely SHG‐inactive. 1,3‐Diazaazulene derivatives are suggested to be potent building blocks for SHG‐active chiral crystals, which are advantageous in high thermal stability, excellent near‐infrared transparency and high degree of designing flexibility. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献