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971.
972.
Jing Zhang Ling Ye Li‐Xin Wu 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(1):o38-o40
In the 1:1 supramolecular adduct of azopyridine (AZP) and succinic acid (SA) [systematic name: di‐4‐pyridyldiazene–succinic acid (1/1)], C10H8N4·C4H6O4 or AZP·SA, both components lie on inversion centers. Alternating AZP and SA molecules are linked by O—H·N hydrogen bonds to form a linear chain extending in the [31] direction. Between chains there is a strong pyridyl–azo π–π interaction, with a 3.340 Å separation between the inversion center at the mid‐point of the azo bond and the centroid of the pyridine ring; this interaction results in the formation of sheets. 相似文献
973.
We study competitive economy equilibrium computation. We show that, for the first time, the equilibrium sets of the following two markets: 1. A mixed Fisher and Arrow- Debreu market with homogeneous and log-concave utility functions; 2. The Fisher and Arrow-Debreu markets with several classes of concave non-homogeneous utility functions; are convex or log-convex. Furthermore, an equilibrium can be computed as convex opti- mization by an interior-point algorithm in polynomial time. 相似文献
974.
Weiwei Gao Shiyong Ye Mingwang Shao 《Journal of Physics and Chemistry of Solids》2011,72(9):1027-1031
Manganese oxide (Mn3O4) nanoparticles with average diameter of 15 nm were prepared using alcohol solution of manganese chloride as starting material via a facile solution-combusting method. The flame core zone was chosen to prepare mono-dispersed and high crystalline products, which were employed to modify glassy carbon electrode and detect dopamine via cyclic voltammetry. The results exhibited excellent electrochemical sensitivity. A linear relationship between the concentration of dopamine and its oxidation peak current was obtained by differential pulse voltammetry, which will find wide application in the biological detection. 相似文献
975.
976.
Chunye Gong Jie Liu Lihua Chi Haowei Huang Jingyue Fang Zhenghu Gong 《Journal of computational physics》2011,230(15):6010-6022
Graphics Processing Unit (GPU), originally developed for real-time, high-definition 3D graphics in computer games, now provides great faculty in solving scientific applications. The basis of particle transport simulation is the time-dependent, multi-group, inhomogeneous Boltzmann transport equation. The numerical solution to the Boltzmann equation involves the discrete ordinates (Sn) method and the procedure of source iteration. In this paper, we present a GPU accelerated simulation of one energy group time-independent deterministic discrete ordinates particle transport in 3D Cartesian geometry (Sweep3D). The performance of the GPU simulations are reported with the simulations of vacuum boundary condition. The discussion of the relative advantages and disadvantages of the GPU implementation, the simulation on multi GPUs, the programming effort and code portability are also reported. The results show that the overall performance speedup of one NVIDIA Tesla M2050 GPU ranges from 2.56 compared with one Intel Xeon X5670 chip to 8.14 compared with one Intel Core Q6600 chip for no flux fixup. The simulation with flux fixup on one M2050 is 1.23 times faster than on one X5670. 相似文献
977.
Shupeng Liu Ye Sun Heng Chen Suxian Song Yuhong Xu 《Applied biochemistry and biotechnology》2010,162(4):1206-1213
Salvianolic acid B is one of the effective components from the Chinese traditional drug Salvia miltiorrhiza (Danshen), which is widely used as a usual clinic drug for atherosclerosis-related disorder patients in China. But the targeting protein of salvianolic acid B is still not known. The possible targeting proteins of salvianolic acid B were explored by high throughput screening in this paper. Attached to the magnetic nanoparticles, salvianolic acid B was used for screening the high-affinity protein from the displaying cDNA peptide library phage. After biopanning, the selected protein or peptide sequences were used to explore the whole proteins containing the selected sequences in the National Center for Biotechnology Information website using blast. One of the selected phages was carried out by affinity analysis with salvianolic acid B using capillary electrophoresis (CE). The CE results indicated that the protein or peptide on the surface of the selected phages could bind the drug salvianolic acid B. The results are helpful to preliminarily explain the pharmacology of salvianolic acid B. 相似文献
978.
979.
Gong Gu Luxmi P.J. Fisher N. Srivastava R.M. Feenstra 《Solid State Communications》2009,149(47-48):2194-2198
We fabricated high-mobility field-effect transistors based on epitaxial graphene synthesized by vacuum graphitization of both the Si- and C-faces of SiC. Room-temperature field-effect mobilities >4000 cm2/V s for both electrons and holes were achieved, although with wide distributions. By using a high-k gate dielectric, we were able to measure the transistor characteristics in a wide carrier density range, where the mobility is seen to decrease as the carrier density increases. We formulate a simple semiclassical model of electrical transport in graphene, and explain the sublinear dependence of conductivity on carrier density from the view point of the few-layer graphene energy band structure. Our analysis reveals important differences between the few-layer graphene energy dispersions on the SiC Si- and C-faces, providing the first evidence based on electrical device characteristics for the theoretically proposed energy dispersion difference between graphene synthesized on these two faces of SiC. 相似文献
980.
We investigate electronic structure and optical properties of LaMnO3 through density-functional-theory calculations with a recent improved exchange potential. Calculated gaps are consistent with recent experimental values, and calculated optical conductivities and dielectric constants as functions of photon energy are in excellent agreement with low-temperature experimental results. These lead to a satisfactory theoretical understanding of the electronic gaps and optical properties of LaMnO3 without tuning atomic parameters and can help elucidate electronic structures and magnetic properties of other manganite materials. 相似文献