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991.
AV Anyushin DA Mainichev NK Moroz PA Abramov DY Naumov MN Sokolov VP Fedin 《Inorganic chemistry》2012,51(18):9995-10003
The coordination of Cd(2+) with P(CH(2)OH)(3) (THP) in methanol was followed by (31)P and (111)Cd NMR techniques. A cadmium-to-phosphine coordination ratio of 1:3 has been established, and effective kinetic parameters have been calculated. Air oxidation of THP in the presence of CdCl(2) at room temperature produces coordination polymer (3)(∞)[Cd(3)Cl(6)(OP(CH(2)OH)(3))(2)] (1). The same oxidation reaction at 70 °C gives another coordination polymer, (∞)[CdCl(2)(OP(CH(2)OH)(3))] (2). Complexes 1 and 2 are the first structurally characterized complexes featuring OP(CH(2)OH)(3) as a ligand that acts as a linker between Cd atoms. The addition of NaBPh(4) to the reaction mixture gives coordination polymer (∞)[Na(2)CdCl(2)(O(2)P(CH(2)OH)(2))(2)(H(2)O)(3)] (3) with (HOCH(2))(2)PO(2)(-) as the ligand. Coordination polymers 1-3 have been characterized by X-ray analysis, elemental analysis, and IR spectroscopy. 相似文献
992.
993.
V. N. Sokolov O. V. Razgulina V. V. Privesentsev D. V. Petrov 《Bulletin of the Russian Academy of Sciences: Physics》2014,78(9):859-863
A computer study of morphological characteristics using AFM images of a self-organized surface nanopore system in the structure of SiO2/Si(100) is performed. The nanopore system is obtained via Zn ion doping with subsequent thermal annealing. AFM images of the nanopore system are studied using the STIMAN 3D software. A correct quantitative estimate is made of the morphology of this nanopore system using a number of parameters (equivalent diameter, area, total area, and shape coefficient). Estimating the morphology of the self-organized surface nanopore system in the structure of SiO2/Si(100) allows us to narrow the possible practical applications of the resulting system in opto- and nanoelectronics. 相似文献
994.
Levanova S. V. Sul’man E. M. Sokolov A. B. Krasnykh E. L. Glazko I. L. Kenzin A. V. Pozdeev V. A. 《Russian Journal of Applied Chemistry》2009,82(5):884-888
Russian Journal of Applied Chemistry - Process of single-stage hydrogenation of phenol to cyclohexanone with industrial (domestic and imported) palladium catalysts, and also with nanocatalysts... 相似文献
995.
N. V. Kovganko S. N. Sokolov Yu. G. Chernov Zh. N. Kashkan V. L. Survilo 《Chemistry of Natural Compounds》2010,46(5):750-755
New derivatives of steroidal 6-ketoximes containing α-chloropyridine neonicotinoid groups characteristic of bioactive compounds were synthesized by formation of oximes of cholestane
and stigmastane 3β,5-dihydroxy-6-ketosteroids with O-(2-chloropyridin-5-ylmethyl)hydroxylamine in the presence of zinc or tin(IV) chloride. 相似文献
996.
Reactions of methyl 3,3,3-trifluoro-2-(pyridin-2-ylimino)propanoates with such nucleophiles and 1,3-binucleophiles as methanol,
p-toluidine, phenylhydrazine, diethyl phosphonate, 2-aminobut-2-enenitrile, benzamidine, and 4,5-dihydro-1,3-thiazol-2-amine
led to the formation of various acyclic 2-substituted methyl 3,3,3-trifluoro-2-(pyridin-2-ylamino)propanoates and trifluoromethyl-containing
heterocyclic N-substituted 2-aminopyridine derivatives: 4,5-dihydro-1H-pyrroles, 4,5-dihydro-1H-imidazol-5-ones, and 2,3-dihydro-6Himidazo[2,1-b][1,3]thiazol-5-ones. 相似文献
997.
Anton Mishkinis Christian Gentil Sandrine Lanquetin Dmitry Sokolov 《Chaos, solitons, and fractals》2012,45(11):1444-1451
In this paper, we present an algorithm to construct an approximate convex hull of the attractors of an affine iterated function system (IFS). We construct a sequence of convex hull approximations for any required precision using the self-similarity property of the attractor in order to optimize calculations. Due to the affine properties of IFS transformations, the number of points considered in the construction is reduced. The time complexity of our algorithm is a linear function of the number of iterations and the number of points in the output approximate convex hull. The number of iterations and the execution time increases logarithmically with increasing accuracy. In addition, we introduce a method to simplify the approximate convex hull without loss of accuracy. 相似文献
998.
V. I. Denisov I. P. Denisova V. A. Sokolov 《Theoretical and Mathematical Physics》2012,172(3):1321-1327
We discuss the concept of natural geometry for a physical field. We show that using this concept to solve problems of nonlinear electrodynamics allows simply studying basic effects of nonlinear electrodynamics arising when weak electromagnetic waves propagate in external electromagnetic fields. 相似文献
999.
Sokolov MN Adonin SA Sinkevich PL Vicent C Mainichev DA Fedin VP 《Dalton transactions (Cambridge, England : 2003)》2012,41(33):9889-9892
ESI-MS based methodology for the rapid reactivity screening of [PW(11)O(39)RhCl](5-) and [PW(11)O(39)Ir(H(2)O)](4-) toward various metalation-intended substrates (reagents with an activated C-H bond, boronic acids and organotin compounds) is presented. Formation of a series of new organometallic POM derivatives with Rh-R (R = malonate, phenylacetate, CH(3), Ph, ferrocenyl) and Ir-R (R = CH(3)) bonds is reported. 相似文献
1000.
Ramešová S Sokolová R Degano I Bulíčková J Zabka J Gál M 《Analytical and bioanalytical chemistry》2012,402(2):975-982
The natural flavonoid compounds quercetin (3,3′,4′,5,7-pentahydroxyflavone) and luteolin (3′,4′,5,7-tetrahydroxyflavone) are
important bioactive compounds with antioxidative, anti-allergic, and anti-inflammatory properties. However, both are unstable
when exposed to atmospheric oxygen, which causes degradation and complicates their analytical determinations. The oxidative
change of these flavonoids was observed and followed by UV–visible spectrophotometry, both in aqueous and ethanolic solutions.
The distribution of the degradation products in aqueous media was monitored by LC–MS and LC–DAD analysis. The amounts of oxidative
reaction products increase with the exposure time. The oxidative degradation reduces the pharmacological efficiency of these
antioxidants and renders analytical determination inaccurate. The oxidative changes in flavonoid test solutions can explain
the inconsistent dissociation constants reported in the literature. Dissociation constants of quercetin and luteolin were
determined both by alkalimetric titration and by UV–visible spectrophotometry under deaerated conditions. The values pK
1 = 5.87 ± 0.14 and pK
2 = 8.48 ± 0.09 for quercetin, and pK
1 = 5.99 ± 0.32 and pK
2 = 8.40 ± 0.42 for luteolin were found. 相似文献