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991.
J. B. Cruz Jr. S. V. Drakunov M. A. Sikora 《Journal of Optimization Theory and Applications》1996,88(2):267-295
In this paper, the decision making problem in continuoustime dynamic systems is considered for the situation with two decision makers and a hierarchical decision structure. The leader-follower strategy is studied. To implement the leader's strategy, we propose to use a sliding mode approach, which allows the leader to constrain the state of the system within some manifold of the state space and forces the follower to choose the strategy preferable for the leader. The corresponding sliding manifolds are derived from the classical variational problem formulation for a class of systems whose right-hand side is affine with respect to the two control inputs. Numerical examples are considered with simulations to illustrate the technique.The authors wish to express their thanks to Dr. Vadim Utkin for his helpful discussions. 相似文献
992.
993.
994.
Harold P. Benson 《Journal of Global Optimization》1995,6(3):231-251
This article performs a geometrical analysis of the efficient outcome setY
E
of a multiple objective convex program (MLC) with linear criterion functions. The analysis elucidates the facial structure ofY
E
and of its pre-image, the efficient decision setX
E
. The results show thatY
E
often has a significantly-simpler structure thanX
E
. For instance, although both sets are generally nonconvex and their maximal efficient faces are always in one-to-one correspondence, large numbers of extreme points and faces inX
E
can map into non-facial subsets of faces inY
E
, but not vice versa. Simple tests for the efficiency of faces in the decision and outcome sets are derived, and certain types of faces in the decision set are studied that are immune to a common phenomenon called collapsing. The results seem to indicate that significant computational benefits may potentially be derived if algorithms for problem (MLC) were to work directly with the outcome set of the problem to find points and faces ofY
E
, rather than with the decision set. 相似文献
995.
Frequency domain photon migration (FDPM) technique was employed to investigate the structure factors of dense, polydisperse colloidal suspensions. The angle-integrated structure factors, [S(q)], extracted from FDPM measurements of scattering properties at volume fractions ranging from 0.05 to 0.4, were compared with the values predicted from the polydisperse hard sphere Percus-Yevick (HSPY) model, as well as decoupling approximation (DA) and local monodisperse approximation (LMA) models that incorporated independently measured particle size information. Results show that the polydisperse HSPY model is the most suitable for accounting for particle interactions which predominantly arise from volume exclusion effects. Furthermore, the influence of size polydispersity upon [S(q)] is most significant at high volume fractions. The static structure factors at small wave vector q, S(0), were also assessed from dual wavelength FDPM measurements by using the small wave number approximation as well as the local monodisperse approximation. The measured S(0) agrees well with the values predicted by the polydisperse HSPY model. 相似文献
996.
Otto J. Scherer 《Angewandte Chemie (International ed. in English)》1985,24(11):924-943
Multiply bonded systems with low coordination number (one to three) involving phosphorus and its homologues, whether isolable or generated in situ at a metal complex, are versatile ligands that can function as two-, four-, six- or eight-electron donors to transition metal fragments and that may be coordinated in η1 (terminal), η2 (side-on), edge- or face-bridging modes. The (p-p)π bonding system of the ligand is thereby rendered capable of addition and intra- or intermolecular cycloaddition reactions. Some of the polycyclic species thus generated represent novel, polydentate ligands. 相似文献
997.
多元线性回归—同时单点沉淀滴定同时测定卤素及硫氰酸盐混合物中各组分 总被引:3,自引:2,他引:3
本文将多元线性回归分析用于单点沉淀滴定法,同时测定了卤素及硫氰酸盐混合物各组分深度,讨论了方法原理、回归方程、对15个二元、三元及四元混合样品进行了测定,均得到满意结果。 相似文献
998.
Jian-bin Song Qing-yong Chen Min-qiao Ren Xiao-hong Sun Hui-liang Zhang Hong-fang Zhang Shu-yun Wang Zhi-shen Mo 《高分子科学》2006,(2):187-193
The wide-angle X-ray diffraction (WAXD) patterns of isothermally crystallized Nylon 1212 show that γ-form crystals form below 90℃ and the α-form crystals can exist above 140℃. In the temperature range of 90-140℃, the α-form and γ-form crystals coexist. Variable-temperature WAXD exhibits that the nylon 1212 γ-form does not show crystal transition on heating, while α-form isothermally crystallized at 160℃ exhibits Brill transition at a little higher than 180℃ on heating. The multiple melting behaviors of Nylon 1212 isothermally crystallized from melt come from a complex mechanism of different crystal structures, dual lamellar population and melting-recrystallization. In polarized optical microscope (POM) observations, Nylon 1212 isothermally crystallized at 175℃ shows the ringed banded spherulites. However, at temperatures below 160℃ the ringed banded image disappears, and cross-extinct spherulites are formed. 相似文献
999.
Understanding the factors influencing the stability of protein mutants is an important task in molecular and computational biology. In this work, we have approached this problem by examining the relative importance of secondary structure and solvent accessibility of the mutant residue for understanding/predicting the stability of protein mutants. We have used hydrophobic, electrostatic and hydrogen bond free energy terms and nine unique physicochemical, energetic and conformational properties of amino acids in the present study and these parameters have been related with changes in thermal stability (DeltaTm) of all the single mutants of lysozymes based on single and multiple correlation coefficients. As expected the properties reflecting hydrophobicity and hydrophobic free energy play a major role to distinguish stabilizing and destabilizing mutants. The hydrophobic free energy due to carbon and nitrogen atoms distinguish the stability of coil and strand mutations to the accuracy of 100 and 90%, respectively. In agreement with previous results, the subgroup classification based on secondary structure and the information about its location in the structure yielded good relationship with the experimental DeltaTm. We revealed that the secondary structure information is equally or more important than solvent accessibility for understanding the stability of protein mutants. The comparison of amino acid properties with free-energy terms indicate that the energetic contribution explains the mutant stability better in coil region whereas the amino acid properties do better in strand region. Further, the combination of free energies with amino acid properties increased the correlation significantly. The present study demonstrates the importance of classifying the mutants based on secondary structure to the stability of proteins upon mutations. 相似文献
1000.
本文将多元线性回归分析用于单点PH滴定中,同时测定极弱酸或碱混合物含量。对 十个五元 极弱碱混合样进行了测定,获得满意结果。 相似文献