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971.
Inspired by previous works on approximations of optimization problems and recent papers on the approximation of Walrasian and Nash equilibria and on stochastic variational inequalities, the present paper investigates the approximation of Nash equilibria and clarifies the conditions required for the convergence of the approximate equilibria via a direct approach, a variational approach, and an optimization approach. Besides directly addressing the issue of convergence of Nash equilibria via approximation, our investigation leads to a deeper understanding of various notions of functional convergence and their interconnections; more importantly, the investigation yields improved conditions for convergence of the approximate Nash equilibria via the variational approach. An illustrative application of our results to the approximation of a Nash equilibrium in a competitive capacity expansion model under uncertainty is presented. 相似文献
972.
Dichlorodiphenyltrichloroethane,1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its main metabolites have been paid much more attention, and present paper describes a new process for the rapid determination of such pollutants in environmental water samples based on dispersive liquid–liquid microextraction (DLLME) and high performance liquid chromatography with ultraviolet detector, which has merits such as high enrichment factor and sensitivity, low cost and easy to operate. Significant parameters such as extraction solvent and dispersive solvent type and volume, pH, extraction time and centrifuging time, which would have important impact on the enrichment of target pollutants, have been investigated in detail. The results exhibited that excellent performance could be achieved with carbon tetrachloride and acetonitrile as the extraction solvent and dispersive solvent, respectively. Under the optimal conditions, excellent linear relationship was gained in the range of 1.0–50 μg L−1, and detection limits were in the range of 0.32–0.51 μg L−1. The precisions of the proposed method were in the range of 2.80–7.50% (RSD). The proposed method was validated with real water samples, and the results indicated the spiked recoveries were in the range of 85.58–119.6% and the established method was very good and competitive in the determination of DDT and its metabolites. 相似文献
973.
974.
Qing Pang Jian‐Min Zhang Ke‐Wei Xu Vincent Ji 《Surface and interface analysis : SIA》2009,41(10):785-793
The monolayer (ML) and submonolayer Pt on both terminations of PbTiO3(110) polar surface have been studied by using density functional theory (DFT) with projector‐augmented wave(PAW) potential and a supercell approach. The most favored ML Pt arrangements on PbTiO and O2 terminations are the hollow site and the short‐bridge site, respectively. By examining the geometries of different ML arrangements, we know that the dominant impetus for stability of the favored adsorption site for PbTiO termination is the Pt–Ti interaction (mainly from covalent bonding), while that for O2 termination is the Pt–O interaction (mainly from ionic bonding). In addition, the appearance of the gap electronic states in the outermost layers of each termination indicates that a channel for charge transfer between adsorbed layer and substrate is formed. Moreover, the interface hybridization between Pt 5d and O 2p orbitals is also observed, especially for ML Pt on O2 termination. The stability sequences for various arrangements of 1/2 ML Pt adsorption conform well with those of ML Pt adsorption, and the most stable arrangement is energetically more favorable than the corresponding ML coverage in the view of adsorption energy maximization. The behavior, i.e. the increase in adsorption energy with decrease in coverage, indicates that Pt? Pt interactions weaken those between Pt and the substrate. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
975.
Xiao-Meng Chong Chang-Qin Hu Yan-Chun Feng Huan-Huan Pang 《Vibrational Spectroscopy》2009,49(2):196-203
A universal classification model has been developed for identification of 26 different products of cephalosporins for injection using near-infrared (NIR) spectroscopy. A total of 324 batches of the 26 products, from 166 manufacturers in China, were used in the study. The classification model was a principle component analysis (PCA)-based method consisting of a primary identification library with four sub-libraries. The accuracy and specificity of the model were tested and were both found to be approximately 95%. The transfer of the classification model between different instruments of the same brand and the same instrument model has been investigated in this study. This study has shown that it is feasible to build a universal classification model to quickly screen for counterfeit drugs in the open market and distribution channels. 相似文献
976.
Wintersweet Branch‐Like C/C@SnO2/MoS2 Nanofibers as High‐Performance Li and Na‐Ion Battery Anodes
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Huimin Zhou Xin Xia Pengfei Lv Jin Zhang Zengyuan Pang Dawei Li Yibing Cai Qufu Wei 《Particle & Particle Systems Characterization》2017,34(12)
Structure and morphology of molybdenum disulfide (MoS2) play an important role in improving its reversible lithium storage and sodium storage as anodes. In this study, a facile method is developed to prepare C/C@SnO2/MoS2 nanofibers with MoS2 nanoflakes anchoring on the core–shell C/C@SnO2 nanofibers through hydrothermal reaction. By adjusting the concentration of MoS2 precursors, the synthesized MoS2 with different slabs dimensions, size, and morphologies are obtained, constituting budding and blooming wintersweet branch‐like composite structure, respectively. Owing to scattered MoS2 nanoparticles and sporadic MoS2 nanoflakes, the budding wintersweet branch‐like composite nanofibers processes less slabs of staking in number and large specific surface area. Benefiting from the exposed C@SnO2 shell layer, the synergistic effect among SnO2, carbon, and MoS2 is strengthened, which maximizes the advantage of each material to exhibit stable specific capacities of 650 and 230 mAh g?1 for Li‐ion batteries and Na‐ion batteries after 200 cycles. 相似文献
977.
使用有限元方法分析了在激光辐照条件下,KDP晶体已加工表面存在的残余内应力、微裂纹及微孔等多种微纳米加工表层缺陷对晶体激光损伤阈值的影响。通过分析发现:KDP晶体微纳米加工表层缺陷的存在,会影响晶体表面的温度场及热应力场的分布,使入射激光的能量积聚在缺陷附近的很小范围内,造成晶体缺陷处产生局部熔融现象,从而使KDP晶体产生损伤,降低KDP晶体的激光损伤阈值。针对微纳米表层的微裂纹进行了损伤阈值测试实验,结果表明微裂纹的存在会降低KDP晶体的激光损伤阈值(约降低3J/cm2),实验结果与仿真结果符合得很好。 相似文献
978.
979.
提出用CCD漫透射成像法测量激光强度时空分布和激光功率,给出了测量原理, 简要叙述了装置总体结构,介绍了测量装置各部分,给出了散射屏的散射特性,重点分析了光路布局、镜头焦距、光圈、景深、滤光片的参数选择,介绍了数据处理软件,给出了激光强度分布测量实验结果。结果表明:漫透射成像法测量激光强度时空分布是可行的,该装置测量强度分布分辨力高达5 mm;测量功率准确、可靠,测量不确定度小于6%,使用方便,实现了在小空间内对大光斑进行功率和强度分布的同时准确测量。 相似文献
980.
C. M. Wang M. Q. Pang 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,74(1):19-25
Out-of-plane spin and charge responses to the terahertz
field for a clean two-dimensional electron gas with a Rashba
spin-orbit interaction in the presence of an in-plane magnetic field
are studied. We show that the characteristic optical spectral
behavior is remarkably different from that of the system in the
absence of in-plane magnetic fields. It is found that the optical
spin polarization normal to the plane is nonzero even for this clean
system, in sharp contrast to the static case. Due to the combined
effect of spin-orbit coupling and in-plane magnetic field, both
diagonal and off-diagonal components of optical charge conductivity
tensor are nonvanishing. It is indicated that one can control the
spin polarization and the optical current by adjusting the optical
frequency. In addition, the out-of-plane spin polarization and
conductivities strongly rely on the direction of the external
magnetic field. Nevertheless, they meet different angle-dependent
relations. This dynamical out-of-plane spin polarization could be
measured by the time-resolved Kerr rotation technique. 相似文献