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21.
Sergei D. Kirik Julia N. Zaitseva Igor S. Yakimov Nikolay N. Golovnev 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):i159-i160
Lithium sodium aluminium fluoride was obtained as a white powder by melting a stoichiometric mixture of AlF3, NaF and LiF at 1223 K, and then cooling to 923 K and sintering at this temperature for 4 h. The ab initio crystal structure determination was carried out using X‐ray powder diffraction techniques. The monoclinic structure of LiNa2AlF6 can be related to cubic elpasolite. The Li and Al atoms lie on inversion centres. The main octahedral AlF6 structural elements are not deformed, but are rotated slightly with respect to the unit‐cell axes. The Li atoms have octahedral coordinations, whereas the Na atoms have cubo‐octahedral coordinations. The Na coordination polyhedron is distorted in comparison with that of elpasolite. 相似文献
22.
V. A. Sergeev L. P. Yur'eva N. N. Zaitseva A. Yu. Vasil'kov A. S. Kogan D. N. Kravtsov 《Russian Chemical Bulletin》1986,35(10):2111-2113
Conclusion A mixture of isomeric 1,2,4- and 1,3,5-triphenylbenzenes and their complexes with chromium and also organic and organochromium polymers were formed in the reaction of phenylacetylene with chromium vapors under high vacuum.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2307–2309, October, 1986.The authors thank S. P. Solodovnikow for recording the EPR spectrum and N. I. Vasyukova for recording the mass spectrum. 相似文献
23.
K. V. Zaitsev S. S. Karlov M. V. Zabalov A. V. Churakov G. S. Zaitseva D. A. Lemenovskii 《Russian Chemical Bulletin》2005,54(12):2831-2840
Titanatrane CpTi(OCH(CH3)CH2)3N (3) was prepared by the reaction of CpTiCl3 with N(CH2CH(CH3)OH)3 in the presence of triethylamine. The reaction of CpTi(OMe)3 (8) with N(CH2CH2OH)2(CH2CHPhOH), erythro-N(CH2CH2OH)2(CHPhCHPhOH), and N(CH2CH2OH)2(CH2CPh2OH) gave cyclopentadienyltitanatranes 12–14. Compound 8 reacts with threo-N(CH2CH2OH)2(CHPhCHPhOH) to give a mixture of threo-CpTi(OCH2CH2)2(OCHPhCHPh)N and threo-MeOTi(OCH2CH2)2(OCHPhCHPh)N. Slow hydrolysis of the latter product gave threo-[Ti3O(OMe){(OCH2CH2)2− (OCHPhCHPh)N} 3]2, which was studied by X-ray diffraction analysis. The crystal structures of 3 and 12 were also determined by X-ray diffraction analysis. The titanium coordination polyhedron in these complexes is a distorted
trigonal bipyramid in which the equatorial positions are occupied by three oxygen atoms and the axial positions contain the
N atom and the Cp group. The titanium—nitrogen distances (2.313(2), 2.291(2) Å in two independent molecules of 3 and 2.271(2) Å in compound 12) confirm the presence of Ti←N transannular interaction.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2736–2744, December, 2005. 相似文献
24.
M. A. Varfolomeev K. V. Zaitseva I. T. Rakipov B. N. Solomonov 《Russian Journal of General Chemistry》2010,80(3):402-407
The measurements of enthalpies of triethylamine and tri-n-butylamine dissolution in aliphatic alcohols and, vice versa, of aliphatic alcohols in amines were carried out. Enthalpies
of specific interactions in the studied systems were calculated. The enthalpy of specific interaction determined in the alcohol
medium, are significantly less than those obtained at dissolving alcohols in amines. The mechanism of specific interaction
of amines with alcohols is discussed. Enthalpies of cooperative hydrogen bonds of tertiary amines with alcohol clusters are
calculated. The dependences between the enthalpies of hydrogen bond and the spatial structure of interacting molecules are
revealed. 相似文献
25.
Yu. K. Tovbin V. N. Komarov E. S. Zaitseva 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(10):2096-2100
Times of metastable droplet relaxation to their equilibrium state are calculated at saturated vapor pressures, depending on the droplet size. It is shown that for small droplets with radius R = 6 molecular diameters (or ~2 nm) the relaxation times are ~1 ns (which is comparable to the characteristic flight times of rarefied gas molecules). For large droplets with radius R ~ 800 molecular diameters, the relaxation times are as long as 10 μs. At a fixed droplet radius (6 ≤ R ≤ 800), the range of variation in relaxation time from the melting point to the critical temperature does not exceed one order of magnitude: the lower the temperature, the slower the relaxation process. 相似文献
26.
V. V. Vysotskii V. I. Roldughin O. Ya. Uryupina I. N. Senchikhin A. V. Zaitseva 《Colloid Journal》2016,78(3):315-321
The formation processes, structure, geometric parameters, and conductivity are studied for thin composite films prepared from nanodispersions of silver particles with diameters smaller than 10 nm by the moving meniscus method. The thickness and conductivity of the films are determined as functions of the mass concentration of a precursor (AgNO3) and the concentration (size) of silver nanoparticles. Some of these functions are nonmonotonic. The dependences of the conductivity on these parameters are found to have the character of a percolation transition. Heterogeneous crystallization of soluble components of the colloidal solutions on silver nanoparticles plays an essential role in the formation of the films. 相似文献
27.
Michael I. Bruce Martin Jevric Mark E. Smith Natasha N. Zaitseva 《Journal of organometallic chemistry》2006,691(3):361-370
The syntheses of several diynylgold(I) phosphine complexes, including Au(CCCCH){P(tol)3} (1), Au(CCCCSiMe3)(PR3) (R = Ph 2-Ph, tol 2-tol), Au(CCCCFc)(PPh3) (3), {(tol)3P}Au(CC)nAu{P(tol)3} [n = 2 (4), 3 (6), 4 (7)], {(Ph3P)Au}CCCC{Au[P(tol)3]} (5), [ppn][Au{CCCCAu[P(tol)3]}2] (8), [Au2(μ-I)(μ-dppm)2][Au(CCCCSiMe3)2] (9), Hg{CCCCAu(PR3)}2 (R = Ph 10-Ph, tol 10-tol) and {(triphos)Cu}CCCC{Au[P(tol)3]} (11) are described. Of these, the X-ray molecular structures of 1, 2-tol, 3, 4 and 9 have been determined. 相似文献
28.
Reactions of platinum(II) chloro-phosphine complexes with Co3(μ3-CCCCCSiMe3)(μ-dppm)(CO)7 in the presence of NaOMe have given the compounds Pt{CCCC-μ3-C[Co3(μ-dppm)(CO)7]}2(dppe) (1), trans-Pt{CCCC-μ3-C[Co3(μ-dppm)(CO)7]}2(PEt3)2 (2) and trans-Pt{CCCC-μ3-C[Co3(μ-dppm) (CO)6(PPh3)]}2(PPh3)2 (3), each of which contains two Co3 clusters linked by C5 chains to the Pt centre. Electrochemical studies (CVs) show the presence of both oxidation and reduction processes, the latter probably occurring on the CCo3 cores. Ready reductive elimination of {Co3(μ-dppm)(CO)7}2(μ3:μ3-C10) occurs from 1 upon heating. The X-ray study of 3 was carried out using synchrotron radiation (Advanced Photon Source, Argonne, IL) to confirm its structure. 相似文献
29.
Kirill V. Zaitsev Yulia A. Piskun Yuri F. Oprunenko Sergey S. Karlov Galina S. Zaitseva Irina V. Vasilenko Andrei V. Churakov Sergei V. Kostjuk 《Journal of polymer science. Part A, Polymer chemistry》2014,52(9):1237-1250
The aluminum complexes containing two iminophenolate ligands of the type (p‐XC6H4NCHC6H4O‐o)2AlR' (R′=Me ( 3, 4 ) or R′=O(CH2)4OCH=CH2 ( 5, 6 ), X=H ( 3, 5 ), F( 4, 6 )) were synthesized and characterized by 1H, 13C NMR spectroscopy, and X‐ray crystallography. The reaction of AlMe3 with two equivalents of substituted iminophenols gave five‐coordinated {ONR}2AlMe ( 3, 4 ) complexes. Subsequent reaction of these methyl complexes with unsaturated alcohol, HO(CH2)4OCH=CH2, resulted in target compounds 5 and 6 in a good yield. It was shown that the complexes ( 3 ‐ 6 ) are monomeric in solution (NMR) and in solid state (X‐ray analysis). The catalytic activity of the complexes 5 and 6 towards ring‐opening polymerization (ROP) of ?‐caprolactone and d,l ‐lactide was assessed. Complex 5 showed higher activity as compared with 6 , while both of these catalysts induced controlled homo‐ and copolymerization to afford the macromonomers with high content of vinyl ether end groups (Fn > 80%) in a broad range of molecular weights (Mn = 4000–30,000 g mol?1) with relatively narrow MWD (Mw/Mn = 1.1–1.5). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1237–1250 相似文献
30.
V. V. Lemanov V. K. Yarmarkin V. M. Egorov G. A. Pankova N. V. Zaitseva L. A. Markova 《Physics of the Solid State》2012,54(2):346-349
It has been shown that the phase transitions observed at temperatures of about 250 K in crystals of protein amino acids and
of their compounds grown from water solutions are related to drops of these solutions trapped by crystals in their growth. 相似文献