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171.
The purpose of this article is to examine the effects of five univariate scoring techniques for rank order categorical data and the results of analyses using each of the techniques for five‐ and ten‐point bi‐polar adjective scales. The effect of scoring method and scale length is assessed for the resultant distance to multivariate normality, inter‐item reliability, discriminant analysis, least squares regression and logistic regression. For these data, the strongest effect of scoring was on distance to multivariate normality and determination of significant variables. 相似文献
172.
Dr. Ana M. Ortuño Dr. Pablo Reiné Prof. Luis Álvarez de Cienfuegos Dr. Irene R. Márquez Dr. Wynand Dednam Prof. Enrico B. Lombardi Prof. Juan J. Palacios Dr. Edmund Leary Prof. Giovanna Longhi Prof. Vladimiro Mujica Dra. Alba Millán Dra. M. Teresa González Linda A. Zotti Dra. Delia Miguel Prof. Juan M. Cuerva 《Angewandte Chemie (International ed. in English)》2023,62(16):e202218640
We report on the chemical design of chiral molecular junctions with stress-dependent conductance, whose helicity is maintained during the stretching of a single molecule junction due to the stapling of both ends of the inner helix. In the reported compounds, different conductive pathways are observed, with clearly different conductance values and plateau-length distributions, attributed to different conformations of the helical structures. The large chiro-optical responses and the potential use of these molecules as unimolecular spin filters have been theoretically proved using state-of-the-art Density Functional Theory (DFT) calculations, including a fully ab-initio estimation of the CISS-originating spin polarization which is done, for the first time, for a realistic molecular system. 相似文献
173.
Linda Lesmak 《Discrete Mathematics》1976,14(2):165-169
A graph G of order p ? 3 is called n-hamiltonian, 0 ? n ? p ? 3, if the removal of any m vertices, 0 ? m ? n, results in a hamiltonian graph. A graph G of order p ? 3 is defined to be n-hamiltonian, ?p ? n ? 1, if there exists ?n or fewer pairwise disjoint paths in G which collectively span G. Various conditions in terms of n and the degrees of the vertices of a graph are shown to be sufficient for the graph to be n-hamiltonian for all possible values of n. It is also shown that if G is a graph of order p ? 3 and , then G is n-hamiltonian. 相似文献
174.
Görbitz CH Nilsen M Szeto K Tangen LW 《Chemical communications (Cambridge, England)》2005,(34):4288-4290
Cocrystallized acetonitrile solvent molecules located inside 5.2 A channels in the crystal structure of L-leucyl-L-serine have been replaced by I2 molecules with full retention of the peptide scaffold. 相似文献
175.
Transport in Porous Media - Membrane filtration of feed containing multiple species of particles is a common process in the industrial setting. In this work, we propose a model for filtration of a... 相似文献
176.
177.
The theory outlined in Part I is applied to the problem of a cantilever beam struck transversely at any point by a mass which subsequently adheres to the beam. In the subsequent motion, slope and velocity discontinuities propagate outwards from the point of impact. Solutions for the velocity and deflection of the various segments of the beam are obtained for the case of linear strain-hardening, and simpler approximate solutions are derived for the case of low impact velocity and/or slight strain-hardening. The discontinuity propagating towards the free end of the beam always comes to rest before it reaches this end, but for sufficiently high values of impact mass and velocity, and a strain-hardening parameter, one or more reflections of the discontinuity may occur at the fixed end of the beam and at the point of impact. 相似文献
178.
Li Chen Milor L.S. Ouyang C.H. Maly W. Yeng-Kaung Peng 《Semiconductor Manufacturing, IEEE Transactions on》1999,12(3):313-322
Variation in channel length degrades circuit reliability and yield. A common way to compensate for this problem is to increase the mean channel length, which, unfortunately, degrades circuit performance for digital circuits. One source of channel length variation is lithography, during which the line width is influenced by local layout patterns. It is possible to compensate for this effect by resizing transistor gates appropriately on the mask. However, the effectiveness of the correction is limited by constraints such as the mask correction resolution. To determine how to design a good correction scheme with limited resources, we have developed a method to compare different correction algorithms in terms of their impact on the performance of one of the main functional blocks in a state-of-the-art microprocessor. In particular, to evaluate correction algorithms while avoiding the high cost associated with generating multiple mask sets and fabricating product wafers with each of these mask sets, we present a method for predicting the correction results using simulation. Our methodology involves a DRC-based approach for gate resizing, along with critical path simulation for evaluating circuit performance. In-line CD measurement data were used to measure the impact of the proximity effect on transistor channel length. Electrical test results were used to calibrate the device models for circuit simulation 相似文献
179.
180.
A discrete-time model for an age-structured population in a patch-type environment is presented and analyzed. Comparison techniques for difference equations are used to find sufficient conditions for population persistence or extinction. The persistence and extinction theorem is used to define the critical patch number, the threshold for population persistence. Several examples are presented which illustrate the results of the theorems. The model is applied to a watersnake population. 相似文献