全文获取类型
收费全文 | 858篇 |
免费 | 16篇 |
国内免费 | 4篇 |
专业分类
化学 | 481篇 |
晶体学 | 9篇 |
力学 | 26篇 |
数学 | 88篇 |
物理学 | 274篇 |
出版年
2021年 | 20篇 |
2020年 | 16篇 |
2019年 | 12篇 |
2018年 | 24篇 |
2017年 | 15篇 |
2016年 | 33篇 |
2015年 | 7篇 |
2014年 | 25篇 |
2013年 | 60篇 |
2012年 | 40篇 |
2011年 | 40篇 |
2010年 | 32篇 |
2009年 | 26篇 |
2008年 | 43篇 |
2007年 | 33篇 |
2006年 | 38篇 |
2005年 | 26篇 |
2004年 | 17篇 |
2003年 | 28篇 |
2002年 | 14篇 |
2001年 | 17篇 |
2000年 | 14篇 |
1998年 | 13篇 |
1997年 | 6篇 |
1996年 | 6篇 |
1993年 | 6篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 7篇 |
1985年 | 9篇 |
1983年 | 9篇 |
1982年 | 8篇 |
1981年 | 10篇 |
1979年 | 10篇 |
1978年 | 14篇 |
1977年 | 8篇 |
1976年 | 13篇 |
1975年 | 15篇 |
1974年 | 6篇 |
1973年 | 10篇 |
1972年 | 9篇 |
1971年 | 9篇 |
1970年 | 7篇 |
1969年 | 10篇 |
1968年 | 14篇 |
1967年 | 8篇 |
1966年 | 6篇 |
1964年 | 7篇 |
1962年 | 5篇 |
排序方式: 共有878条查询结果,搜索用时 234 毫秒
1.
A dual Ginzburg-Landau model corresponding to SU(3) gluodynamics in the Abelian projection is studied. A string theory describing QCD string dynamics is obtained in this
model. The interaction of static quarks in mesons and baryons is investigated in an approximation to leading order.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 2, 109–114 (25 July 1998) 相似文献
2.
Komarov A. V. Yakovlev I. P. Novikov D. V. Semakova T. L. Zakhs V. E. 《Russian Journal of General Chemistry》2003,73(11):1806-1809
Methylmalonyl dichloride reacts with (2E)-3-phenylacrylamides and (2E)-3-(2-furyl)acrylamide to give the corresponding E-isomeric 2-substituted 4-hydroxy-5-methyl-6H-1,3-oxazin-6-ones. The reaction of methylmalonyl dichloride with acrylamide afforded N-(3-chloropropionyl)-2-methylmalonamic acid. The structure of the products was confirmed by the 1H and 13C NMR, IR, and UV spectra. 相似文献
3.
D. Chiladze J. Carbonell S. Dymov V. Glagolev M. Hartmann V. Hejny A. Kacharava I. Keshelashvili A. Khoukaz H.R. Koch V. Komarov P. Kulessa A. Kulikov G. Macharashvili Y. Maeda T. Mersmann S. Merzliakov S. Mikirtytchiants A. Mussgiller M. Nioradze H. Ohm F. Rathmann R. Schleichert H.J. Stein H. Ströher Yu. Uzikov S. Yaschenko C. Wilkin 《Physics letters. [Part B]》2006
4.
We study the problem of existence and uniqueness of generalized solutions of nonlinear vector boundary-value problems arising in the physically nonlinear theory of thermoelasticity. We prove the convergence of iteration processes in the space W 1 2. 相似文献
5.
Komarov A. V. Yakovlev I. P. Novikov D. V. Zakhs V. E. 《Russian Journal of General Chemistry》2003,73(12):1936-1941
4-Hydroxy-5-methyl(phenyl)-2-styryl-6H-1,3-oxazin-6-ones react with hydrazine and phenylhydrazine to give the corresponding 3,5-substituted triazoles. Treatment of the title compounds with ethanol and methanol leads to formation of N-cinnamoylmalonamates. The structure of the products was confirmed by the IR and 1H and 13C NMR spectra. 相似文献
6.
7.
Smirnov Yu. N. Komarov B. A. Kushch P. P. Ponomareva T. I. Lantsov V. M. 《Russian Journal of Applied Chemistry》2002,75(2):265-275
To control the structural contributions of the polycondensation and polymerization curing of epoxy resins, the curing kinetics of the composites diepoxide-tertiary amine and diepoxide-(primary + tertiary) amines is studied by the isothermal calorimetry. 相似文献
8.
I. V. Komarov A. V. Turov S. V. Popov Yu. L. Slominskii M. Yu. Kornilov 《Theoretical and Experimental Chemistry》1991,27(2):179-182
It was established by PMR with lanthanide shift reagents that the charge in anionic cyanine dyes with a linear chromophore is concentrated at the ends of the polymethine chain, while in compounds containing a vinylene group in the chromophore it is concentrated in the region of the five-membered ring. The results are compared with the data from13C NMR spectroscopy and relaxation measurements in the presence of Gd(fod)3. The validity of the conclusions is also considered.Kiev University. Institute of Organic Chemistry, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Teoreticheskaya i Éksperimental'naya, Vol. 27, No. 2, pp. 197–201, March–April, 1991. Original article submitted December 20, 1989. 相似文献
9.
Yu K Singh S Patrito N Chu V 《Langmuir : the ACS journal of surfaces and colloids》2004,20(25):11161-11168
Using cadium oxide (CdO) as the Cd precursor and tri-n-octylphosphine selenide (TOPSe) as the Se source, TOP-capped and TOP/tri-n-octylphosphine oxide (TOPO)-capped CdSe nanocrystals were synthesized without the use of an acid. The synthetic approach involved the addition of a TOPSe/TOP solution into a CdO/TOP solution with or without TOPO at one temperature and subsequent growth at a lower temperature. The temporal evolution of the optical properties, namely, absorption and luminescence, of the growing nanocrystals was monitored in detail. A comprehensive examination on the control of the photoluminescence (PL) properties was performed by systematically varying the TOP/TOPO weight ratio of the reaction media. Surprisingly, a rational choice of 100% TOP or 80% TOP was found to produce "quality" nanocrystals when monitored under the present experimental conditions and growth-time scale. The term "quality" is mainly based on the sharp features and rich substructure exhibited in the absorption spectra of the growing nanocrystals, as well as the sharp features in the emission spectra with narrow full width at half-maximum (fwhm). There are two distinguishable stages of growth: an early stage (<5 min) and a later stage. TOP plays a major role in the control of a slow growth rate in the early stage, while TOPO controls slow growth in the later stage. The optical sensitivity of the growing nanocrystals when dispersed in nonpolar or polar solvents was studied, including two size-dependent parameters, namely, the solvent sensitivity (PL intensity) and nonresonant Stokes shift (NRSS). The insights gained from the present study enable a synthetic approach in which high-quality CdSe nanocrystals are achieved with high synthetic reproducibility. 相似文献
10.
Conclusions The vinylation of -silicon-containing carboxylic acids by acetylene under the influence of zinc and cadmium salts was investigated. A method was found for producing organosilicon complex vinyl esters. 相似文献