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991.
992.
This paper presents a spatiotemporal super-resolution method to enhance both the spatial resolution and the frame rate in a hybrid stereo video system. In this system, a scene is captured by two cameras to form two videos, including a low spatial resolution with high-frame-rate video and a high spatial resolution with low-frame-rate video. For the low-spatial-resolution video, the low-resolution frames are spatially super-resolved by the high-resolution video via the stereo matching, the bilateral overlapped block motion estimation, and the adaptive overlapped block motion compensation algorithms, while for the low-frame-rate video, those missed frames are interpolated using the high-resolution frames obtained by fusing the disparity compensation and the motion compensation frame rate up-conversion. Experimental results demonstrate that the proposed mixed spatiotemporal super-resolution method has a more significant contribution to both the subjective and objective qualities than the pure spatial super-resolution or the frame rate up-conversion.  相似文献   
993.
994.
995.
The carboranylpyrrole polymers are functional materials with superior thermal resistance and conducting performances. The carboranylpyrrole structures and Laplacian bond order (LBO) of carborane moiety, as well as the thermal resistance and conducting properties of carboranylpyrrole dimers or polymers, were investigated theoretically. The 11B NMR chemical shifts of 3-(2-methyl-o-carboranyl)alkyl-1H-pyrrole monomers (CP-1 to CP-5) were calculated and analyzed. The average LBO values of some characteristic chemical bonds in the carborane cages of CP-1 to CP-5 molecules were calculated. It is found that the average LBO values of carborane moieties change slightly with the increase in alkyl chain length. The temperature resulting in about 15–20 % weight loss for CP-1, CP-3, CP-4 and CP-5 polymers is predicted to be more than 700 °C. Apart from the C–C bonds in carborane moieties of 3-(2-R-o-carboranyl)propyl-1H-pyrrole (R = CH2OH, CH2OCH3, CN, COCl, Ph) substituents, the LBO values of other bonds in these cages change slightly relative to that in the molecule of 3-(2-methyl-o-carboranyl)propyl-1H-pyrrole (CP-3). The C–C bond LBO values in the carborane cages of these substituents with electron-donating groups (R = CH2OH, CH2OCH3) are bigger than that in CP-3, while those values in those substituents with electron-withdrawing groups (R = CN, COCl, Ph) are smaller than that in CP-3. The polymerization activity calculated for CP-1 to CP-5 monomers increases with the increase in alkyl chain length. The calculated orbital energy gap (?E LUMO?HOMO) of CP-1 to CP-5 dimers decreases with the increase in alkyl chain length, and accordingly, the electronic conductivity has the potential to increase. In addition, the calculated band gaps of CP-1 to CP-5 dimers cell models also decrease with the increase in alkyl chain length.  相似文献   
996.
Two new 1,3-bi(4-pyridyl)propane-based cadmium(II) complexes, [Cd(Bpp)2(Nas)2] n (I) and [Cd(Bpp)2(Na)2(H2O)2] (II) (Bpp = 1,3-bi(4-pyridyl)propane, Nas = 2-aminonaphthalene-1-sulfonate, and Na = 1-naphthoate) (CIF files CCDC nos. 1429589 (I), 1429590 (II)) have been hydrothermally synthesized by varying carboxylate- or sulfonate-containing coligands. Structural analyses reveal that, complex I with monodentate Nas ligands exhibits a two-dimensional (2D) layered motif extended by equatorial Bpp connectors. By contrast, complex II modified by monodentate Na ligands exhibit discrete mononuclear structure. Althouth the Nas/Na coligands showed the same monodentate binding modes, the Bpp ligand exhibits bridging or terminal binding modes in I and II, respectively. So it is obvious that the competitive coordination in the present mixed-ligands system is responsible for the aggregation or dissociation of mononuclear structural units. Furthermore, both of the two compounds are linked to 3D supramolecular architecture by intermolecular C–H···O hydrogen bonding or C–H···π stacking interactions, exhibiting strong fluorescent emissions resulting from the ligand-to-metal or Na?-based intraligand charge transfer at room temperature, which can be hopefully used as fluorescent materials.  相似文献   
997.
Lithium–sulfur (Li–S) batteries have been recognized as promising substitutes for current energy‐storage technologies owing to their exceptional advantage in energy density. The main challenge in developing highly efficient and long‐life Li–S batteries is simultaneously suppressing the shuttle effect and improving the redox kinetics. Polar host materials have desirable chemisorptive properties to localize the mobile polysulfide intermediates; however, the role of their electrical conductivity in the redox kinetics of subsequent electrochemical reactions is not fully understood. Conductive polar titanium carbides (TiC) are shown to increase the intrinsic activity towards liquid–liquid polysulfide interconversion and liquid–solid precipitation of lithium sulfides more than non‐polar carbon and semiconducting titanium dioxides. The enhanced electrochemical kinetics on a polar conductor guided the design of novel hybrid host materials of TiC nanoparticles grown within a porous graphene framework (TiC@G). With a high sulfur loading of 3.5 mg cm?2, the TiC@G/sulfur composite cathode exhibited a substantially enhanced electrochemical performance.  相似文献   
998.
We study the existence of at least one weak solution for a class of elliptic Navier boundary value problems involving the p(x)-biharmonic operator. Our technical approach is based on variational methods. In addition, an example to illustrate our results is given.  相似文献   
999.
通过二维红外光谱研究了GdmSCN/KSCN=1/1,GdmSCN/KS13CN=1/1和GdmSCN/KS13C15N=1/1三种混合晶体在熔融和溶液状态下的共振和非共振的分子间振动能量传递的性质. 在这些样品中,给体/受体的能量差越大,能量传递越慢. 而能量传递的快慢与拉曼光谱无关. 非共振能量传递与给体/受体的能量差的关系不能用声子补偿的机理来描述. 相反,它们的关系却可以用退相位机理来定量描述. 在熔融状态下,共振和非共振能量速率与温度的依赖关系也与退相位机理的预测相符合. 这一系列的结果表明只要分子的运动(平动和转动)远远快于非共振能量传递速率,那么退相位机理不仅在溶液中占主导,而且在熔融状态下(纯液体,不含溶剂)也占主导.  相似文献   
1000.
It is well known that a rigid in-plane motion can be decomposed into a translation and a rotation around an origin. Based on our previous work, we first extend the Helgason-Ludwig consistency condition (HLCC) to cover a general rigid motion in fan-beam geometry. Then, we model the general motion by several parameters, and develop an iterative scheme for estimation of the in-plane motion parameters. This scheme determines the motion parameters by numerically minimizing an objective function constructed based on the HLCC. After the motion parameters are estimated, image reconstruction can be performed to compensate for the motion effects. Finally, we implement the algorithm and evaluate its performance in numerical simulations.  相似文献   
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