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991.
为了实现对薄膜和镀层材料厚度的微区无损分析,利用多毛细管X光会聚透镜和多毛细管X光平行束透镜设计并搭建了普通实验室X射线光源的共聚焦微束X射线荧光测厚仪,对该共聚焦测厚仪的性能进行了系统表征。利用该测厚仪测定了厚度约为25μm的Ni独立薄膜样品和压于硅基表面厚度约为15μm的Ni薄膜样品厚度,对应它们的相对测量误差分别为3.7%和6.7%。另外,还对厚度约为10μm Ni薄膜样品的厚度均匀性进行了测量。该共聚焦测厚仪可以对样品进行微区深度分析,并且具有元素分辨能力,从而使得该谱仪可以测量多层膜样品不同层的膜厚,在薄膜和镀层厚度表征领域具有潜在的应用。 相似文献
992.
993.
Yulong Ji Hongbin Ma Fengmin SuGuoyou Wang 《Experimental Thermal and Fluid Science》2011,35(4):724-727
The effect of Al2O3 particles on the heat transfer performance of an oscillating heat pipe (OHP) was investigated experimentally. Water was used as the base fluid for the OHP. Four size particles with average diameters of 50 nm, 80 nm, 2.2 μm, and 20 μm were studied, respectively. Experimental results show that the Al2O3 particles added in the OHP significantly affect the heat transfer performance and it depends on the particle size. When the OHP was charged with water and 80 nm Al2O3 particles, the OHP can achieve the best heat transfer performance among four particles investigated herein. In addition, it is found that all particles added in the OHP can improve the startup performance of the OHP even with 20 μm Al2O3 particles. 相似文献
994.
Jianhua Huang a Lianzhong Zhang a b Suyuan Yu c a School of Physics Nankai University Tianjin China b State Key Laboratory of Loess Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China c Institute of Nuclear Energy New Energy Technology Tsinghua University Beijing China 《中国颗粒学报》2011,9(1)
A representative human upper respiratory tract (URT) with idealized oral region and asymmetric tracheo-bronchial (TB) airway has been modeled, and laminar-to-turbulent airflow for typical inhalation modes as well as micro-particle transport and deposition has been simulated using CFX10.0 software from Ansys Inc. on a personal computer. The asymmetric TB airway could not be replaced by an extended straight tube as outlet of the oral region while investigating the tracheal airflow field and particle depositio... 相似文献
995.
Wei Zhang Richard S. Blackburn Abbas A. Dehghani-Sanij 《中国颗粒学报》2008,6(1):24-29
In the preparation of surface coatings made of conductive composites consisting of conductive particulate fillers in a soft matrix, cracks will develop with increase of the particulate loading, which is believed to be related to the nucleophilic addition reaction between glycidyl end-capped poly (bisphenol A-co-epichlorohydrin) and isophorone diisocyanate molecules. This curing reaction is responsible for the generation of crosslinking network throughout the coatings. The influence of solid particle loading on the chemical reaction may be described as a volume-excluded effect, that is, the high solid particle loading will occupy the space between the functional groups thus preventing the chemical reaction to take place. As a direct consequence, the cross-linking network cannot develop properly due to the insufficiency of curing reaction. This will lead to the generation of cracks, as was supported by FT-IR analysis in this work. 相似文献
996.
997.
Adrian Constantin Mats Ehrnstrm Gabriele Villari 《Nonlinear Analysis: Real World Applications》2008,9(4):1336-1344
Using phase plane analysis we show that within the framework of linear water wave theory the particle paths in a deep-water wave are not closed: there is a forward drift over a period, which decreases with greater depth. 相似文献
998.
A. Jafari S.M. Mousavi P. Kolari 《Communications in Nonlinear Science & Numerical Simulation》2008,13(8):1615-1626
In some diseases there is a focal pattern of velocity in regions of bifurcation, and thus the dynamics of bifurcation has been investigated in this work. A computational model of blood flow through branching geometries has been used to investigate the influence of bifurcation on blood flow distribution. The flow analysis applies the time-dependent, three-dimensional, incompressible Navier–Stokes equations for Newtonian fluids. The governing equations of mass and momentum conservation were solved to calculate the pressure and velocity fields. Movement of blood flow from an arteriole to a venule via a capillary has been simulated using the volume of fluid (VOF) method. The proposed simulation method would be a useful tool in understanding the hydrodynamics of blood flow where the interaction between the RBC deformation and blood flow movement is important. Discrete particle simulation has been used to simulate the blood flow in a bifurcation with solid and fluid particles. The fluid particle method allows for modeling the plasma as a particle ensemble, where each particle represents a collective unit of fluid, which is defined by its mass, moment of inertia, and translational and angular momenta. These kinds of simulations open a new way for modeling the dynamics of complex, viscoelastic fluids at the micro-scale, where both liquid and solid phases are treated with discrete particles. 相似文献
999.
Sebastian M.F. Raupach 《Optik》2010,121(13):1194-1197
Holography is a powerful tool as it codes information, e.g. on 3D positions in a particle field in a single 2D hologram. In digital holography, the holograms are recorded on a digital image sensor. It is a particular challenge to visualize a digital hologram's depth information, such that it can be understood intuitively while retaining the advantages of a numerical reconstruction. In this contribution it is suggested and demonstrated how a numerically constructed volume can be used to calculate stereoscopic views, which even in the case of non-diffuse illumination allow for an intuitive visualization of particles’ positions in 3D space. 相似文献
1000.
Self-adaptive velocity particle swarm optimization for solving constrained optimization problems 总被引:4,自引:0,他引:4
Particle swarm optimization (PSO) is originally developed as an unconstrained optimization technique, therefore lacks an explicit
mechanism for handling constraints. When solving constrained optimization problems (COPs) with PSO, the existing research
mainly focuses on how to handle constraints, and the impact of constraints on the inherent search mechanism of PSO has been
scarcely explored. Motivated by this fact, in this paper we mainly investigate how to utilize the impact of constraints (or
the knowledge about the feasible region) to improve the optimization ability of the particles. Based on these investigations,
we present a modified PSO, called self-adaptive velocity particle swarm optimization (SAVPSO), for solving COPs. To handle
constraints, in SAVPSO we adopt our recently proposed dynamic-objective constraint-handling method (DOCHM), which is essentially
a constituent part of the inherent search mechanism of the integrated SAVPSO, i.e., DOCHM + SAVPSO. The performance of the
integrated SAVPSO is tested on a well-known benchmark suite and the experimental results show that appropriately utilizing
the knowledge about the feasible region can substantially improve the performance of the underlying algorithm in solving COPs. 相似文献