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101.
Dr. Manjeet Kumar Dr. Thomas Simonson Dr. Gilles Ohanessian Dr. Carine Clavaguéra 《Chemphyschem》2015,16(3):658-665
The association of Mg2+ and H2PO4? in water can give insights into Mg:phosphate interactions in general, which are very widespread, but for which experimental data is surprisingly sparse. It is studied through molecular dynamics simulations (>100 ns) by using the polarizable AMOEBA force field, and the association free energy is computed for the first time. Explicit consideration of outer‐sphere and two types of inner‐sphere association provides considerable insight into the dynamics and thermodynamics of ion pairing. After careful assessment of the computational approximations, the agreement with experimental values indicates that the methodology can be extended to other inorganic and biological Mg:phosphate interactions in solution. 相似文献
102.
Insights into the Complexity of Weak Intermolecular Interactions Interfering in Host–Guest Systems 下载免费PDF全文
Dawei Zhang Dr. Bastien Chatelet Eloisa Serrano Dr. Olivier Perraud Dr. Jean‐Pierre Dutasta Prof. Dr. Vincent Robert Prof. Dr. Alexandre Martinez 《Chemphyschem》2015,16(14):2931-2935
The recognition properties of heteroditopic hemicryptophane hosts towards anions, cations, and neutral pairs, combining both cation–π and anion–π interaction sites, were investigated to probe the complexity of interfering weak intermolecular interactions. It is suggested from NMR experiments, and supported by CASSCF/CASPT2 calculations, that the binding constants of anions can be modulated by a factor of up to 100 by varying the fluorination sites on the electron‐poor aromatic rings. Interestingly, this subtle chemical modification can also reverse the sign of cooperativity in ion‐pair recognition. Wavefunction calculations highlight how short‐ and long‐range interactions interfere in this recognition process, suggesting that a disruption of anion–π interactions can occur in the presence of a co‐bound cation. Such molecules can be viewed as prototypes for examining complex processes controlled by the competition of weak interactions. 相似文献
103.
《Comptes Rendus Chimie》2015,18(8):883-890
The one-step synthesis of silylated 1,2,4,5-tetraaryl imidazoles by use of a series of M/SAPO-34 (M: Fe, Co, Mn, and Cu) nanocatalysts and subsequent silylation reactions is described. Cu/SAPO-34 catalyst has the highest activity in improving the efficiency of the heterogeneous cyclo-condensation of an aldehyde, benzil, ammonium acetate and a primary aromatic amine in water under ultrasonic irradiation. Some of imidazole derivatives are studied with a view to the synthesis of a series of new, multi-substituted imidazoles containing organosilyl groups including carbosilanes (Si–C) and silyl ethers (Si–O). 相似文献
104.
Jun Hu Dr. Zilong Zhao Prof. Qiaoling Liu Prof. Mao Ye Bingqiang Hu Jing Wang Prof. Weihong Tan 《化学:亚洲杂志》2015,10(7):1519-1525
Guanine (G)‐rich oligonucleotides have attracted considerable interest as therapeutic agents. Two G‐rich aptamers were selected against epidermal growth factor receptor (EGFR)‐transfected A549 cells, and their G‐rich domains (S13 and S50) were identified to account for the binding of parental aptamers. Circular dichroism (CD) spectra showed that S13 and S50 bound to their targets by forming parallel quadruplexes. Their binding, internalization, and antiproliferation activity in cancer and noncancer cells were investigated by flow cytometry and 3‐(4,5‐dimethylthiazol‐2‐yl)‐5‐(3‐carboxymethoxyphenyl)‐2‐(4‐sulfophenyl)‐2H‐tetrazolium (MTS) assay, and compared with those of nucleolin‐binding AS1411 and thrombin‐binding aptamer. The two truncated aptamers (S13 and S50) have good binding and internalization in cancer cells and noncancer cells; however, only S50, similar to AS1411, shows potent antiproliferation against cancer cells. Our data suggest that tumor‐selective antiproliferation of G‐rich oligonucleotides does not directly depend on the binding of the G‐rich aptamer to cells. 相似文献
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108.
《Indagationes Mathematicae》2017,28(1):145-169
A matchbox manifold with one-dimensional leaves which has equicontinuous holonomy dynamics must be a homogeneous space, and so must be homeomorphic to a classical Vietoris solenoid. In this work, we consider the problem, what can be said about a matchbox manifold with equicontinuous holonomy dynamics, and all of whose leaves have at most polynomial growth type? We show that such a space must have a finite covering for which the global holonomy group of its foliation is nilpotent. As a consequence, we show that if the growth type of the leaves is polynomial of degree at most 3, then there exists a finite covering which is homogeneous. If the growth type of the leaves is polynomial of degree at least 4, then there are additional obstructions to homogeneity, which arise from the structure of nilpotent groups. 相似文献
109.
Dean Crnković B.G. Rodrigues Sanja Rukavina Vladimir D. Tonchev 《Discrete Mathematics》2017,340(10):2472-2478
This paper completes the enumeration of quasi-symmetric 2- designs supported by the dual code of the binary linear code spanned by the lines of , initiated in Rodrigues and Tonchev (2015). It is shown that supports exactly 30,264 nonisomorphic quasi-symmetric 2- designs. The automorphism groups of the related strongly regular graphs are computed. 相似文献
110.
《Mathematische Nachrichten》2017,290(14-15):2341-2355
In this paper, we use the powerful tool Milnor bases to determine all the locally symmetric left invariant Riemannian metrics up to automorphism, on 3‐dimensional connected and simply connected Lie groups, by solving system of polynomial equations of constants structure of each Lie algebra . Moreover, we show that E 0(2) is the only 3‐dimensional Lie group with locally symmetric left invariant Riemannian metrics which are not symmetric. 相似文献