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971.
972.
采用胶体化学法制备了稳定的SnO2纳米粒子(nanoparticleNP)水溶胶,用膜天平和原位布儒斯特角显微镜(BAM)考察了经典成膜材料花生酸(AA)在此水溶胶气-液界面的成膜性,并用LB膜技术在不同基底上制得了单层和多层AA-Sno2NP复合LB膜,通过TEM、小角X-ray、IR和UV-VIS光谱,进一步考察了该有序组装体的结构和周期性,以及组装作中Sno2纳米粒子的形貌、粒度分布和表面聚集状态.结果表明,用这种方法能够制得粒度分布均匀、农致密的Sno2纳米粒子复合LB膜,并且多层复合膜具有良好的周期性. 相似文献
973.
在以正己烷-异丙醇为移动相的体系中,用ChiralpakAD和ChiralcelOD作为手性固定相对15种乙炔基氮杂环丙烷类化合物对映体进行了HPLC手性拆分。这些化合物至少在一支柱上能基线级分离。 相似文献
974.
We examine the variation and similarity of the native structures predicted from various accessible-surface-area solvent models for peptide Met-enkephalin. Both ECEPP/2 and ECEPP/3 force fields have been used in conjunction with ten different sets of accessible-surface-area parameterization. The native structures were determined by an implementation of the basin hopping Monte Carlo technique. The results suggest that the implicit solvent models examined in this study should be employed in computer simulations with extreme caution. In addition, the effect of fixing or not fixing the peptide angles omega has been examined. We conclude that fixing omega generally gives rise to a poor prediction. 相似文献
975.
Jian-Feng Cai Raymond H. Chan Lixin Shen Zuowei Shen 《Advances in Computational Mathematics》2009,31(1-3):87-113
How to recover missing data from an incomplete samples is a fundamental problem in mathematics and it has wide range of applications in image analysis and processing. Although many existing methods, e.g. various data smoothing methods and PDE approaches, are available in the literature, there is always a need to find new methods leading to the best solution according to various cost functionals. In this paper, we propose an iterative algorithm based on tight framelets for image recovery from incomplete observed data. The algorithm is motivated from our framelet algorithm used in high-resolution image reconstruction and it exploits the redundance in tight framelet systems. We prove the convergence of the algorithm and also give its convergence factor. Furthermore, we derive the minimization properties of the algorithm and explore the roles of the redundancy of tight framelet systems. As an illustration of the effectiveness of the algorithm, we give an application of it in impulse noise removal. 相似文献
976.
This paper studies the problem of optimal control of the viscous Camassa–Holm equation. The existence and uniqueness of weak solution to the viscous Camassa–Holm equation are proved in a short interval. According to variational method, optimal control theories and distributed parameter system control theories, we can deduce that the norm of solution is related to the control item and initial value in the special Hilbert space. The optimal control of the viscous Camassa–Holm equation under boundary condition is given and the existence of optimal solution to the viscous Camassa–Holm equation is proved. 相似文献
977.
978.
979.
In this paper, by using the corrector method we give another proof of the quenched invariance principle for the random walk on the infinite random graph generated by a one-dimensional long-range percolation under the conditions that the connection probability p(1)=1 and the percolation exponent s>2. The key step of the proof is the construction of the corrector. We show that the corrector can be constructed under either s∈(2,3] or s>3, though the corresponding underlying measures may be different. As an application of the main result we get a new lower bound of the quenched diagonal transition probability for the random walk. 相似文献
980.
The luminescence spectra of Eu(3+) at a T(h) point-group site in the hexanitritolanthanate systems Cs(2)NaEu((14)NO(2))(6), Cs(2)NaEu((15)NO(2))(6), Rb(2)NaEu((14)NO(2))(6), Cs(2)LiEu((14)NO(2))(6), and Cs(2)NaY((14)NO(2))(6):Eu(3+) have been recorded between 19,500 and 10,500 cm(-1) at temperatures down to 3 K. The spectra comprise magnetic-dipole-allowed zero phonon lines, odd-parity metal-ligand vibrations, internal anion vibrations, and lattice modes, with some weak vibrational progressions based upon vibronic origins. With the aid of density functional theory calculations, the vibrational modes in the vibronic sidebands of transitions have been assigned. The two-center transitions involving NO(2)(-) stretching and scissoring modes are most prominent for the (5)D(0) → (7)F(2) hypersensitive transition. The onset of NO(2)(-) triplet absorption above 20,000 cm(-1) restricts the derived Eu(3+) energy-level data set to the (7)F(J) (J = 0-6) and (5)D(0,1) multiplets. A total of 21 levels have been included in crystal-field energy-level calculations of Eu(3+) in Cs(2)NaEu(NO(2))(6), using seven adjustable parameters, resulting in a mean deviation of ~20 cm(-1). The comparison of our results is made with Eu(3+) in the double nitrate salt. In both cases, the fourth-rank crystal field is comparatively weaker than that in europium hexahaloelpasolites. 相似文献