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91.
92.
Serdar Karademir 《Linear and Multilinear Algebra》2013,61(6):707-710
In this note we formulate necessary and sufficient conditions for strong solvability and feasibility of systems of linear interval equations in terms of absolute value inequalities. 相似文献
93.
磁约束等离子体中杂质(特别是高Z杂质)的存在将大大增强等离子体辐射功率损失,破坏等离子体的约束性能。杂质行为的定量研究首先要求对杂质测量的光谱诊断系统进行绝对强度标定,获得灵敏度响应曲线。介绍了EAST托卡马克上的快速极紫外光谱仪系统绝对强度的原位标定方法。在波长范围20~150Å内,通过对比极紫外(EUV)波段连续轫致辐射强度的计算值和测量值得到光谱仪的绝对强度标定。在此过程中,首先由(523±1) nm范围内可见连续轫致辐射强度的绝对测量值计算出有效电荷数Zeff,进而结合电子温度和密度分布计算EUV波段连续轫致辐射强度;EUV波段连续轫致辐射强度的测量值即为不同波长处探测器的连续本底计数扣除背景噪声计数值。对于较长波段范围130~280Å,通过对比等离子体中类锂杂质离子(Fe23+,Cr21+,Ar15+)和类钠杂质离子(Mo31+,Fe15+)发出的共振谱线对(跃迁分别为1s22s 2S1/2-1s22p 2P1/2, 3/2及2p63s 2S1/2-2p63p 2P1/2, 3/2)强度比的理论和实验值进行相对强度标定。其中共振谱线对强度比的理论值由辐射碰撞模型计算得到,模型中处在各个能级的离子数主要由电子碰撞激发,去激发以及辐射衰变三个过程决定。两种方法相结合,实现了光谱仪20~280Å范围的绝对强度标定。考虑轫致辐射、电子温度及电子密度的测量误差,绝对标定误差约为30%。在绝对标定的基础上,我们对杂质特征谱线强度进行绝对测量,并将测量结果与杂质输运程序结合ADAS(Atomic Data and Analysis Structure)原子数据库计算得到的模拟值进行比较,进而估算等离子体中的杂质浓度。 相似文献
94.
Alberto Paradela Miguel Marcilla Laura Ferreira Marisol Fernández Francisco García-del Portillo 《Talanta》2010,80(4):1496-3398
An evaluation of the ICPL (isotope-coded protein labeling) non-isobaric labeling technique was performed using two different biological models. Two samples containing phage T4 capsids were mixed in a 1:1 ratio after being labeled with the light or heavy versions of the ICPL reagent. The analysis of this proteome demonstrated the feasibility of this approach for differential quantitative proteomics and was employed to optimize the experimental parameters of the ICPL workflow. ICPL-mediated analysis of two more complex proteomes, those of a Salmonella enterica serovar Typhimurium virulent strain and an isogenic attenuated mutant, and its comparison with the results obtained in a 2D-PAGE “classical” approach confirmed that ICPL is a valuable alternative to other labeling techniques currently in use. In addition, our results suggest that labeling at the peptide level instead of following the standard ICPL workflow should increase both the number of proteins quantified and the reliability of the quantification. 相似文献
95.
1 INTRODUCTIONOrganophosphorus compounds are ubiquitous in nature and they have broad applications in the fields of agriculture and medicine. During the past two decades, (-ketophosphonates and their derivatives have attracted considerable attention because these compounds are endowed with special physical, chemical and pharmacological properties due to the proximity of the carbonyl and the phosphoryl groups[1~6]. For example, it is well known that phosphonoformic acid (PFA) is effectiv… 相似文献
96.
97.
J. P. Wesley 《Foundations of Physics Letters》1990,3(4):395-397
Because terrestrial sources radiate in all directions, collimation cannot produce a beam fixed in direction relative to absolute space. Therefore, terrestrial aberration, even though present, cannot be observed; and terrestrial aberration cannot be used to measure the absolute velocity of the closed laboratory (contradicting a prior claim in this journal). In other words, the large parallax of terrestrial sources frustrates the observation of aberration. 相似文献
98.
The problem of finding the dynamically equilibrium shape of a rotating mass of liquid with homogeneous density (lens) submerged in a stratified ocean at rest on the rotating Earth is formulated. An equation for the shape of the interface between water masses is derived. An exact solution of the problem for an anticyclonically rotating lens in a linearly stratified ocean in the neighborhood of the lens depth shows that the dynamically equilibrium shape of the interface is a triaxial ellipsoid inclined with respect to the horizon and similar to an ellipsoid of revolution for real parameters of the phenomenon. The limiting values of the latitudes at which these formations can exist are determined. Degeneration of the shape with decrease in the intrinsic lens angular rate is investigated. 相似文献
99.
100.
Nguyen To Nhu Jose M. R. Sanjurjo Tran Van An 《Proceedings of the American Mathematical Society》1997,125(10):3089-3098
In this second part of our paper, we apply the result of Part 1 to show that the compact convex set with no extreme points, constructed by Roberts (1977), is an AR.