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761.
庞常词 《数学物理学报(A辑)》2001,21(Z1):603-609
该文利用锥压缩和锥拉伸不动点定理给出了非共振奇异Dirichlet边值问题两个正解的存在性. 相似文献
762.
763.
双棒串接Nd3+:YAG激光器 总被引:4,自引:2,他引:2
根据测量的单根Nd3+:YAG棒的热焦距,利用ABCD传输矩阵计算了双棒串接的几种腔型的稳定参量,给出了能够满足高功率、高稳定性激光输出的稳定腔型,实验结果与理论分析基本相符. 相似文献
764.
二粒子部分缠结态的量子隐形传态 总被引:2,自引:1,他引:1
利用三粒子的最大缠结态(即GHZ态)作为量子通道,实现二粒子部分缠结态的隐形传态,其成功几率为1.该方案只需借助一个量子比特作为辅助比特和两次贝尔基测量,其操作均为局域操作且在目前技术条件下可以很容易实现. 相似文献
765.
Sunčica Čanić Barbara Lee Keyfitz Eun Heui Kim 《Bulletin of the Brazilian Mathematical Society》2001,32(3):377-399
From the observation that self-similar solutions of conservation laws in two space dimensions change type, it follows that for systems of more than two equations, such as the equations of gas dynamics, the reduced systems will be of mixed hyperbolic-elliptic type, in some regions of space. In this paper, we derive mixed systems for the isentropic and adiabatic equations of compressible gas dynamics. We show that the mixed systems which arise exhibit complicated nonlinear dependence. In a prototype system, the nonlinear wave system, this behavior is much simplified, and we outline the solution to some typical Riemann problems.Dedicated to Constantine Dafermos on his 60th birthdayResearch supported by the National Science Foundation, grant DMS-9970310.Research supported by the Department of Energy, grant DE-FG-03-94-ER25222 and by the National Science Foundation, grant DMS-9973475 (POWRE).Research supported by the Department of Energy, grant DE-FG-03-94-ER25222 and by the National Science Foundation, grant DMS-0103823. 相似文献
766.
Weitong Cui Huaru Xue Hongda Cheng Haibin Zhang Jinghua Jin Qinglu Wang 《Electrophoresis》2019,40(7):1107-1112
The Bradford assay is one of the most commonly used methods for protein quantification. However, in proteomic research, the lysis buffer generally used for dissolving proteins can cause some interference to the assay. The dye reagent of classical Bradford assay contains 8.50% (w/v) phosphoric acid, which is an important factor relating to the color yield of the assay. In this study, the phosphoric acid content in dye reagent was increased to 9.35% (w/v), 10.20% (w/v), and 11.05% (w/v) to evaluate the changes of interference and the effects of lysis buffer on the interaction between proteins and dye reagent. Results show that lysis buffer not only causes background interference but also affects the protein–dye chromogenic process. Analysis of different components in the lysis buffer showed that carrier ampholyte is the main factor that introduces interference to the Bradford assay. Detergents are well‐known interfering compounds in the Bradford assay, but CHAPS and octyl b‐D‐glucopyranoside only cause slight interference. When the amount of phosphoric acid was increased from 8.50%(w/v) to 10.20% (w/v), the sensitivity of the Bradford assay to proteins in lysis buffer was increased, and the interference delivered by lysis buffer was considerably reduced. 相似文献
767.
Jian Zhang Ziyi Li Kan Zhan Runqing Sun Zhizhi Sheng Miao Wang Shuli Wang Xu Hou 《Electrophoresis》2019,40(16-17):2029-2040
Two dimensional nanomaterials including graphene, hexagonal boron‐nitride, molybdenum disulfide, etc., provide immense potentials for separation applications. However, the tradeoff between selectivity and permeability in choosing 2D nanomaterial‐based membrane is inevitable, limiting the progress on separation efficiency for mass industrial applications. To target these issues, versatile strategies such as the rational design of predefined interlayer channels, membrane nanopores, and reasonable functionalization, as well as new mechanisms have been emerged. In this review, we introduce the recent progress on separation mechanisms of 2D nanomaterial‐based membranes with different structures (including the interlayer channels type and the membrane nanopores type) and their inner surface functionalization. Moreover, the interface designs are discussed, in terms of employing dynamic liquid–liquid/liquid–gas interfaces, to advance the selectivity and permeability of the membranes. We further discuss the variety of separation applications based on 2D nanomaterial‐based membranes. The authors hope this review will inspire the active interest of many scientists in the area of the development and application of membrane science. 相似文献
768.
Quench dynamics of two one-dimensional harmonically trapped bosons bridging attraction and repulsion
ABSTRACTWe unravel the nonequilibrium quantum dynamics of two harmonically confined bosons in one spatial dimension when performing an interaction quench from finite repulsive to attractive interaction strengths and vice versa. A closed analytical form of the expansion coefficients of the time-evolved two-body wavefunction is derived, while its dynamics is determined in terms of an expansion over the postquench eigenstates. For both quench scenarios the temporal evolution is analysed by inspecting the one- and two-body reduced density matrices and densities, the momentum distribution and the fidelity. Resorting to the fidelity spectrum and the eigenspectrum we identify the dominant eigenstates of the system that govern the dynamics. Monitoring the dynamics of the above-mentioned observables we provide signatures of the energetically higher-lying states triggered by the quench. 相似文献
769.
770.
The strain energy density theory and the near crack line analysis method are applied to investigate an eccentric crack loaded by two pairs of tensile point forces in a finite plate. The minimum values of SED in the vicinity of the crack tip are determined, the initial growth orientation of crack are determined. Obtained is the elastic-plastic solution near the crack line of an eccentric crack loaded by two pairs of point tensile forces under large scale yielding condition. More specifically, the near field solution contains the unit normal vector of the elastic-plastic boundary and the elastic-plastic stress field. The length of the plastic zone along the crack line is found to vary with the external load and the bearing capacity of a finite plate with an eccentric crack loaded by two pairs of tensile point forces. Compared with small scale yielding condition, the normalized load obtained is higher than those under small scale yielding condition when the length of the plastic zone is the same. 相似文献