全文获取类型
收费全文 | 99081篇 |
免费 | 5417篇 |
国内免费 | 4629篇 |
专业分类
化学 | 56257篇 |
晶体学 | 1333篇 |
力学 | 5582篇 |
综合类 | 322篇 |
数学 | 11833篇 |
物理学 | 33800篇 |
出版年
2023年 | 749篇 |
2022年 | 1709篇 |
2021年 | 2117篇 |
2020年 | 2310篇 |
2019年 | 2507篇 |
2018年 | 2892篇 |
2017年 | 2823篇 |
2016年 | 3486篇 |
2015年 | 2409篇 |
2014年 | 3477篇 |
2013年 | 4919篇 |
2012年 | 5056篇 |
2011年 | 5354篇 |
2010年 | 4251篇 |
2009年 | 4255篇 |
2008年 | 4453篇 |
2007年 | 4173篇 |
2006年 | 3804篇 |
2005年 | 3375篇 |
2004年 | 3036篇 |
2003年 | 2711篇 |
2002年 | 2827篇 |
2001年 | 2547篇 |
2000年 | 1987篇 |
1999年 | 1601篇 |
1998年 | 1534篇 |
1997年 | 1329篇 |
1996年 | 1293篇 |
1995年 | 1077篇 |
1994年 | 1156篇 |
1993年 | 1095篇 |
1992年 | 1062篇 |
1991年 | 1124篇 |
1990年 | 1118篇 |
1989年 | 1039篇 |
1988年 | 917篇 |
1987年 | 914篇 |
1986年 | 881篇 |
1985年 | 921篇 |
1984年 | 915篇 |
1983年 | 822篇 |
1982年 | 800篇 |
1979年 | 801篇 |
1978年 | 812篇 |
1977年 | 806篇 |
1976年 | 919篇 |
1975年 | 812篇 |
1974年 | 844篇 |
1973年 | 847篇 |
1972年 | 752篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
132.
The electrochemical behavior of gatifloxacin (GTFX) and its interaction with natural calf thymus DNA (ctDNA) is investigated by differential pulse voltammetry (DPV) on a carbon paraffined electrode. According to the suggested electrochemical equation, a binding constant of 1.7058 x 10(5) (mol L(-1))(-1) and binding sizes s = 3.09 (base pairs) of GTFX with ctDNA are obtained by nonlinear fit analysis of electrochemical data. The results demonstrate that GTFX has the properties of an intercalative binder. 相似文献
133.
L. V. Miroshnik N. I. Korovnikova Yu. V. Shabadash 《Russian Journal of Inorganic Chemistry》2006,51(4):649-655
The complexing properties of cellulose complexite with respect to copper(II) ions in water-1,4-dioxane (DO) mixtures are determined. The stoichiometry and stability constants of copper(II) complexes with the hydroxamic groups of the polymer are determined. The equilibrium speciation diagrams for the complexes at pH 2.0–6.0 are plotted; stereochemical configurations are suggested. The effect of the solvation parameters of the complexite on complex formation is analyzed. 相似文献
134.
P. A. Neobyavlyayushchy A. A. Dekterev A. A. Gavrilov Yu. I. Storozhev 《Thermophysics and Aeromechanics》2007,14(1):143-151
A complex numerical and experimental investigation of burner devices for a reburning of the anode gas of aluminum production
was carried out. The chosen mathematical model of the processes of aerodynamics, heat exchange, and gas burning was identified
and adapted on the basis of data of real-scale measurements. Basing on computational experiments the optimization of the design
of elements of the system for anode gas detoxication and transport was carried out. A new system was proposed and tested for
reburning the anode gases of electrolysis production, which consists of an improved burner device and a dust-sedimenting chamber
with a possibility of regulating the amount of gas suction. 相似文献
135.
We propose a general idea of obtaining different chains of coupled oscillators with chaotic buffering. As examples, we consider chains of diffusively coupled generalized cubic Schrödinger equations and nonlinear telegraph equations. We also give examples of systems that have an infinite-dimensional chaotic attractor. 相似文献
136.
E. N. Chebotok V. Yu. Novikov I. N. Konovalova 《Russian Journal of Applied Chemistry》2006,79(7):1162-1166
Depolymerization of chitin and chitosan in the course of deacetylation in an alkaline medium was studied, and the influence exerted on the process by the nature and concentration of the alkali (NaOH, KOH) and salts (NaCl, NaI, KI) was examined. 相似文献
137.
It is suggested to take as pH of the precipitation onset of metal hydroxides the pH at which 10% of the initial amount of metal ions has precipitated. An equation for calculating this quantity is presented. 相似文献
138.
Yu. S. Denishchik 《Journal of Applied Spectroscopy》1989,51(5):1167-1170
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 51, No. 5, pp. 777–781, November, 1989. 相似文献
139.
A nonrelativistic deuteron wave function involving the D-wave state and having a correct asymptotic behavior is constructed on the basis of the experimentally measured deuteron charge form factor G C(q) and deuteron structure function A(q). The differential cross section for elastic deuteron-nucleus scattering is calculated by using this wave function and is found to agree with experimental data at an energy of 110 MeV. Integrated cross sections for various processes involving deuteron-nucleus interactions are also calculated. The distribution in the emission angle of the center of mass of the neutron-proton system produced in the diffractive dissociation of 110-MeV deuterons in the field of 208Pb nuclei is obtained. 相似文献
140.
N. V. Khitrich I. I. Seifullina Yu. K. Epimakhov P. A. Ivanchenko 《Russian Journal of Applied Chemistry》2006,79(9):1514-1517
Kinetic features of radical polymerization of styrene initiated by tert-butyl perbenzoate in the presence of tris(N,N-dimethyldithiocarbamato)cobalt(III) (CoL3) and its adduct with iodine (CoL3 · 2I2) were studied. The optimal concentration ratios of the activators and tert-butyl perbenzoate, providing fast styrene polymerization at 338–368 K, were determined. 相似文献