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31.
32.
Shun-Chen Niu 《Queueing Systems》1988,3(2):157-178
We give in this paper a detailed sample-average analysis of GI/G/1 queues with the preemptive-resume LIFO (last-in-first-out) queue discipline: we study the long-run state behavior of the system by averaging over arrival epochs, departure epochs, as well as time, and obtain relations that express the resulting averages in terms of basic characteristics within busy cycles. These relations, together with the fact that the preemptive-resume LIFO queue discipline is work-conserving, imply new representations for both actual and virtual delays in standard GI/G/1 queues with the FIFO (first-in-first-out) queue discipline. The arguments by which our results are obtained unveil the underlying structural explanations for many classical and somewhat mysterious results relating to queue lengths and/or delays in standard GI/G/1 queues, including the well-known Bene's formula for the delay distribution in M/G/l. We also discuss how to extend our results to settings more general than GI/G/1. 相似文献
33.
34.
I. M. Krukovskii M. S. Molchanova A. V. Evtushenko V. A. Shlyapochnikov 《Russian Chemical Bulletin》1998,47(7):1266-1273
The ratio between the numbers of structural formulas of C,H,N,O-containing energetic compounds belonging to the classes of
fuels (low values of the oxygen coefficientA), explosives (mediumA), and oxidants (highA values) was studied by a computer generation procedure. The number of the theoretically possible structural formulas was
found to decrease rapidly on going from fuels to explosives and then to oxidants; this observation agrees with the data on
the numbers of various energetic compounds currently used and proposed. The strategy of the search for new compounds with
the specified properties is described in brief, and its applicability to the search for explosives and oxidants with a small
(up to 12) number of atoms in a molecule is evaluated.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1304–1310, July, 1998. 相似文献
35.
双质谱测定地卟啉取代基组成的解析方法及其应用 总被引:2,自引:0,他引:2
根据卟啉标样的双质谱特征,建立一种计算卟啉环上取代基组成的方法。卟啉的平均分子结构简式衡量其取代基的组成,尤其对地质体中相同碳数的卟啉“混合物”大环外取代基的构成十分有效。 相似文献
36.
本文研究分数扩散过程和其分部积分公式的关系.首先利用Bismut方法给出拉回公式,进而得到分数扩散过程的分部积分公式。反过来,证明了分数扩散过程可由其分部积分公式唯一刻画. 相似文献
37.
Ben Salem Nejib 《Journal of Theoretical Probability》1994,7(2):417-436
We consider hypergroups associated with Jacobi functions
()
(x), (–1/2). We prove the existence of a dual convolution structure on [0,+[i(]0,s
0]{{) =++1,s
0=min(,–+1). Next we establish a Lévy-Khintchine type formula which permits to characterize the semigroup and the infinitely divisible probabilities associated with this dual convolution, finally we prove a central limit theorem. 相似文献
38.
Masakiyo Miyazawa 《Queueing Systems》1994,15(1-4):1-58
We survey the rate conservation law, RCL for short, arising in queues and related stochastic models. RCL was recognized as one of the fundamental principles to get relationships between time and embedded averages such as the extended Little's formulaH=G, but we show that it has other applications. For example, RCL is one of the important techniques for deriving equilibrium equations for stochastic processes. It is shown that the various techniques, including Mecke's formula for a stationary random measure, can be formulated as RCL. For this purpose, we start with a new definition of the rate with respect to a random measure, and generalize RCL by using it. We further introduce the notion of quasi-expectation, which is a certain extension of the ordinary expectation, and derive RCL applicable to the sample average results. It means that the sample average formulas such asH=G can be obtained as the stationary RCL in the quasi-expectation framework. We also survey several extensions of RCL and discuss examples. Throughout the paper, we would like to emphasize how results can be easily obtained by using a simple principle, RCL. 相似文献
39.
Jian-binSong Min-qiaoRen Qing-yongChen Shu-yunWang Qing-xiangZhao Hong-fangZhang 莫志深 《高分子科学》2004,(5):491-496
Based on the X-ray scattering intensity theory and using the approximate expression for the atomic scattering factor, the correction factors for three crystalline peaks and an amorphous peak of Nylon 1212 were calculated and the formula of degree of crystallinity of Nylon 1212 was derived by a graphic multipeak resolution method. The degree of crystallinity calculated from the WAXD method is compatible with those obtained by density and calorimetry methods. 相似文献
40.
T. Wanjun L. Yuwen Z. Hen W. Zhiyong W. Cunxin 《Journal of Thermal Analysis and Calorimetry》2003,74(1):309-315
A new approximate formula for temperature integral is proposed. The linear dependence of the new fomula on x has been established. Combining this linear dependence and integration-by-parts, new equation for the evaluation of kinetic
parameters has been obtained from the above dependence. The validity of this equation has been tested with data from numerical
calculating. And its deviation from the values calculated by Simpson's numerical integrating was discussed. Compared with
several published approximate formulae, this new one is much superior to all other approximations and is the most suitable
solution for the evaluation of kinetic parameters from TG experiments.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献