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排序方式: 共有625条查询结果,搜索用时 15 毫秒
611.
Bayirta V. Egorova Lyubov S. Zamurueva Anastasia D. Zubenko Anna V. Pashanova Artem A. Mitrofanov Anna B. Priselkova Yuri V. Fedorov Alexander L. Trigub Olga A. Fedorova Stepan N. Kalmykov 《Molecules (Basel, Switzerland)》2022,27(10)
A synthetic procedure for the synthesis of azacrown ethers with a combination of pendant arms has been developed and the synthesized ligand, characterized by various techniques, was studied. The prepared benzoazacrown ether with hybrid pendant arms and its complexes with copper and lead cations were studied in terms of biomedical applications. Similarly to a fully acetate analog, the new one binds both cations with close stability constants, despite the decrease in both constants. The calculated geometry of the complexes correlate with the data from X-ray absorption and NMR spectroscopy. Coordination of both cations differs due to the difference between the ionic radii. However, these chelation modes provide effective shielding of cations in both cases, that was shown by the stability of their complexes in the biologically relevant media towards transchelation and transmetallation. 相似文献
612.
Iryna G. Davydenko Aleksei D. Kachkovsky Marina L. Dekhtyar Yurii L. Slominskii Aleksei I. Tolmachev 《Journal of Physical Organic Chemistry》2010,23(2):96-104
On the basis of the 7,8‐dihydrobenzo[c,d]furo[2,3‐f]indole nucleus, a number of unsymmetrical carbocyanines as well as styryl dyes have been synthesized and their absorption spectra have been measured. Starting from the deviations of long‐wavelength maxima, the value of electron‐donor ability D has been estimated for the heterocycle under study and a number of dye end groups have been ranked by their electron‐donor properties. Experimental inferences are supported by the quantum chemically calculated bond length alternations and energy levels for the dyes concerned. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
613.
Khlebnikova Yu. V. Rodionov D. P. Egorova L. Yu. Suaridze T. R. 《Technical Physics》2018,63(12):1771-1783
Technical Physics - The structure of a hafnium crystal undergoing β → α (bcc → hcp) polymorphic transformation upon gradual cooling and the structure of Hf55Ti45 and Hf30Ti70... 相似文献
614.
Sharutin V. V. Egorova I. V. Sharutina O. K. Ivanenko T. K. Adonin N. Yu. Starichenko V. F. Pushilin M. A. Gerasimenko A. V. 《Russian Journal of Coordination Chemistry》2003,29(12):838-844
Tetranuclear organobismuth complex Bi4(O)2(O2CC6H2F3-3,4,5)8 · 26-65Me with four bismuth atoms joined via the bridging carboxylate ligands and oxygen atoms was studied using X-ray diffraction analysis. The coordination sphere of either of the two terminal bismuth atoms contains the chelate carboxylate ligand and the toluene molecule. For the bridging tricoordinated oxygen atoms, the Bi–O distances are 2.083(2), 2.119(2), and 2.276(2) Å. The average distance between the bismuth atom and the center of toluene molecule is equal to 3.131 Å. 相似文献
615.
Nikolay A. Bumagin Alexey V. Kletskov Sergey K. Petkevich Iryna A. Kolesnik Alexander S. Lyakhov Ludmila S. Ivashkevich Alexander V. Baranovsky Peter V. Kurman Vladimir I. Potkin 《Tetrahedron》2018,74(27):3578-3588
New substituted 3-((1H-1,2,3-triazol-1-yl)methyl)-5-arylisoxazoles (aryl?=?Ph, p-Tol) and 2-(5-phenylisoxazol-3-yl)-5-(2-(1-((5-(p-tolyl)isoxazol-3-yl)methyl)-1H-1,2,3-triazol-4-yl)ethyl)-1,3,4-oxadiazole were synthesized by means of click-chemistry procedures. The obtained compounds were used as ligands in preparation of palladium(II) complexes, and the latter proved to be high-turnover-number catalysts for CC cross-coupling reactions under Green Chemistry conditions. One of the ligands was structurally characterized by single crystal X-ray diffraction, and the structure of complexes was determined by 1H, 13C, 15N NMR spectroscopy and quantum-chemical modeling. 相似文献
616.
Egorova I. V. Zhidkov V. V. Zubakina I. N. Rodionova N. A. 《Russian Chemical Bulletin》2020,69(7):1279-1283
Russian Chemical Bulletin - Bis(tetraphenylantimony) malonate was synthesized by the reaction of tetraphenylantimony bromide with silver malonate (the molar ratio was 2:1) in toluene. According to... 相似文献
617.
For a two-class two-node bandwidth sharing network called parking lot network we investigate the tail behavior of the queue
length and sojourn time under light-tailed assumptions. These results extend previous results in the literature obtained for
a single-node network. Explicit conditions are given that indicate whether congestion at the second node influences the large
deviations behavior or not. To overcome the complexities that arise when moving away from the single node case, we rely on
recent results on overloaded bandwidth sharing networks obtained by Borst et al. (2009), and a comparison with the modified
proportional fairness discipline, as introduced by Massoulié (Ann Appl Probab 17: 809–839, 2007). Specifically, our results include upper bounds for the distribution of the number of flows in the network, finiteness of
the moment generating function of the workload, and large-deviations asymptotics for the sojourn time assuming flow size distributions
having a bounded hazard rate. 相似文献
618.
619.
E. A. Egorova V. P. Zubov I. V. Bakeeva E. V. Chernikova E. A. Litmanovich 《Polymer Science Series A》2013,55(9):519-525
The controlled synthesis of oligomeric poly(acrylic acid) via the pseudoliving radical reversible addition-fragmentation chain-transfer polymerization of acrylic acid in bulk is developed. It is shown that, at high concentrations of reversible addition-fragmentation chain-transfer agents, the polymerization of acrylic acid in bulk occurs via the pseudoliving mechanism, as evidenced by a linear increase in the numberaverage molecular mass of oligomers with conversion and a narrow molecular-mass distribution of the reaction products. The surfactant properties and behavior of the oligomers in aqueous solutions are studied. 相似文献
620.
V. V. Sharutin I. V. Egorova N. N. Klepikov E. A. Boyarkina O. K. Sharutina 《Russian Journal of Coordination Chemistry》2009,35(3):186-190
The complexes [Ph3BuP]2+[Bi2I8 · 2Me2C=O]2− (II) and [Ph3BuP]2+[Bi2I8 · 2Me2S=O]2− (III) are synthesized by the reactions of triphenyl(n-butyl)phosphonium iodide (I) with bismuth iodide in acetone and dimethyl sulfoxide. In the cations of complexes I–III, the P atoms have a distorted tetrahedral coordination (CPC angles 106.3(2)°–112.0(3)°). The butyl group in cation I is disordered over two positions. In the binuclear centrosymmetric anions of structures II and III, the octahedrally coordinated bismuth atoms are linked in pairs by two bridging (br) iodine atoms (Bi-Ibr 3.1508(7) and 3.2824(8) ? in compound II, 3.1961(3) and 3.3108(3) ? in complex III), which are coplanar to four terminal (t) iodine atoms (Bi-It 2.9260(7) and 2.9953(6) ? in complex II, 2.9206(3) and 2.9786(3) ? in complex III). The two remaining positions at the bismuth atom are occupied by the iodine atom (Bi-It 2.8531(7) ? in complex II, 2.8984(3) ? in complex III) and O atom of the organic molecule (Bi-O 2.747(6) ? in complex II, 2.507(3) ? in complex III).
Original Russian Text ? V.V. Sharutin, I.V. Egorova, N.N. Klepikov, E.A. Boyarkina, O.K. Sharutina, 2009, published in Koordinatsionnaya
Khimiya, 2009, Vol. 35, No. 3, pp. 188–192. 相似文献