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91.
Nd-YAG激光器三倍频泵浦的染料激光激发Srl原子,热二极管探共振离化信号,获得Srl高Rydberg5sndD2系列双光子激光共振电离谱。实验发现激光汉长调440nm附近时,存在一Sr2准分子吸收光谱带,同时还观测到了5s5p^1P1-5s11d^1D2,5s5p^1P1-4d^23P1混合共振跃迁现象。并对这种瞬态准分子的连续吸收光电离背景的形成和混合共振跃迁的机制作了初步探讨,同时对缓冲气 相似文献
92.
冷却水中异味污染物的LC-GC/FTIR联用分析 总被引:2,自引:0,他引:2
利用在线式高效液相色谱-毛细管气相色谱/傅里叶变换红光谱联用方法分析了某冷却水中的异味污染物。结果表明,污染系苯酚类化合物所致。 相似文献
93.
94.
In an early study the BCS wave function was generalized to include the motion of the center-of-mass of Cooper pairs. An alternative order parameter can be defined on the basis of this motion. In later work, when in copper oxides Bloch orbitals replaced free electrons, nodes were found in the vector space of the Fourier representation of the order parameter. Here that Fourier representation has suggested that the parameter consists of two components, a long wave lengths part which does not contain nodes, a short wave length part which does. The former component is real, and applies deep inside the superconductor, the latter, which is imaginary, in the boundary region. Further, the imaginary component has odd symmetry about the nodal axis. There results an addition of about 0.93π to the relative phase of two adjacent sides of a square superconductor cut along appropriate crystal axis, and embedded in a normal metal. 相似文献
95.
超短激光脉冲操控双量子比特的量子态 总被引:1,自引:1,他引:0
用光与物质相互作用的半经典理论研究了超短激光脉冲与构成双量子比特的二体二能级体系的相互作用,对由不同的激发方式引起的独立双路(Independent Double Path-Ways,IDPW)和相干双路径(Coherent Double Path-Ways,CDPW)进行对比.研究结果表明,与单量子比特相比,双量子比特在超短激光脉冲的作用下,表现出更加丰富的相干性.这种相干特性与体系初态、失谐量和激发的路径都有关.同时,可以利用超短激光脉冲对双量子比特的相干激发,通过调节光脉冲面积来实现量子态的操控. 相似文献
96.
Many studies on hardware framework and routing policy are devoted to reducing the transmission time for a flow network. A time version of the shortest path problem thus arises to find a quickest path, which sends a given amount of data from the unique source to the unique sink with minimum transmission time. More specifically, the capacity of each arc in the flow network is assumed to be deterministic. However, in many real-life networks, such as computer systems, telecommunication systems, etc., the capacity of each arc should be stochastic due to failure, maintenance, etc. Such a network is named a stochastic-flow network. Hence, the minimum transmission time is not a fixed number. We extend the quickest path problem to evaluating the probability that d units of data can be sent under the time constraint T. Such a probability is named the system reliability. In particular, the data are transmitted through two minimal paths simultaneously in order to reduce the transmission time. A simple algorithm is proposed to generate all (d,T)-MPs and the system reliability can then be computed in terms of (d,T)-MPs. Moreover, the optimal pair of minimal paths with highest system reliability could be obtained. 相似文献
97.
This paper considers a two-facility supply chain for a single product in which facility 1 orders the product from facility 2 and facility 2 orders the product from a supplier in each period. The orders placed by each facility are delivered in two possible nonnegative integer numbers of periods. The difference between them is one period. Random demands in each period arise only at facility 1. There are physical storage constraints at both facilities in each period. The objective of the supply chain is to find an ordering policy that minimizes the expected cost over a finite horizon and the discounted stationary expected cost over an infinite horizon. We characterize the structure of the minimum expected cost and the optimal ordering policy for both the finite and the discounted stationary infinite horizon problems. 相似文献
98.
Recent interest in the role of quantum mechanics in the primary events of photosynthetic energy transfer has led to a convergence of nonlinear optical spectroscopy, condensed matter and quantum physics on the topic of energy‐transfer dynamics in pigment‐protein complexes. The convergence of these communities has unveiled a mismatch between the background and terminology of the respective fields. To make connections, a pedagogical guide to understanding the basics of two‐dimensional spectra is provided aimed at researchers with a background in quantum mechanics and condensed matter. 相似文献
99.
In the present paper, the commercial CFD code “Fluent” was employed to perform 2-D simulations of an entire process that included the flow around a fixed circular cylinder, the oscillating cylinder (vortex-induced vibration, VIV) and the oscillating cylinder subjected to shape control by a traveling wave wall (TWW) method. The study mainly focused on using the TWW control method to suppress the VIV of an elastically supported circular cylinder with two degrees of freedom at a low Reynolds number of 200. The cross flow (CF) and the inline flow (IL) displacements, the centroid motion trajectories and the lift and drag forces of the cylinder that changed with the frequency ratios were analyzed in detail. The results indicate that a series of small-scale vortices will be formed in the troughs of the traveling wave located on the rear part of the circular cylinder; these vortices can effectively control the flow separation from the cylinder surface, eliminate the oscillating wake and suppress the VIV of the cylinder. A TWW starting at the initial time or at some time halfway through the time interval can significantly suppress the CF and IL vibrations of the cylinder and can remarkably decrease the fluctuations of the lift coefficients and the average values of the drag coefficients; however, it will simultaneously dramatically increase the fluctuations of the drag coefficients. 相似文献
100.
A model of cavitation bubbles is derived in liquid confined in an elastic sealed vessel driven by ultrasound. In this model, an assumption that the pressure acting on the sealed vessel due to bubble pulsations is proportional to total volume change of bubbles is made. Numerical simulations are carried out for a single bubble and for bubbles. The results show that the pulsation of a single bubble can be suppressed to a large extent in sealed vessel, and that of two matched bubbles with same ambient radius can be further suppressed. However, when two mismatched bubbles have the same ambient radii, an interesting breathing phenomenon takes place, where one bubble pulsates inversely with the other one. Due to this breathing phenomenon the suppression effect becomes weak, so the maximum radii of two mismatched bubbles can be larger than that of a single bubble or that of two matched bubbles in sealed vessel. Besides that, for two mismatched bubbles with different ambient radii, the small one in sealed vessel under some certain parameters can pulsate as strong as or even stronger than that of a single bubble in an open vessel. 相似文献