全文获取类型
收费全文 | 438223篇 |
免费 | 3863篇 |
国内免费 | 1578篇 |
专业分类
化学 | 218801篇 |
晶体学 | 6047篇 |
力学 | 21946篇 |
综合类 | 9篇 |
数学 | 70984篇 |
物理学 | 125877篇 |
出版年
2020年 | 2699篇 |
2019年 | 3034篇 |
2018年 | 13579篇 |
2017年 | 13325篇 |
2016年 | 11604篇 |
2015年 | 4667篇 |
2014年 | 6130篇 |
2013年 | 16577篇 |
2012年 | 15506篇 |
2011年 | 24740篇 |
2010年 | 15313篇 |
2009年 | 15635篇 |
2008年 | 19658篇 |
2007年 | 21842篇 |
2006年 | 12783篇 |
2005年 | 12925篇 |
2004年 | 11895篇 |
2003年 | 11107篇 |
2002年 | 10171篇 |
2001年 | 10679篇 |
2000年 | 8172篇 |
1999年 | 6355篇 |
1998年 | 5447篇 |
1997年 | 5406篇 |
1996年 | 5018篇 |
1995年 | 4746篇 |
1994年 | 4517篇 |
1993年 | 4466篇 |
1992年 | 4907篇 |
1991年 | 5040篇 |
1990年 | 4687篇 |
1989年 | 4637篇 |
1988年 | 4676篇 |
1987年 | 4486篇 |
1986年 | 4310篇 |
1985年 | 5786篇 |
1984年 | 5981篇 |
1983年 | 4956篇 |
1982年 | 5450篇 |
1981年 | 5232篇 |
1980年 | 5090篇 |
1979年 | 5250篇 |
1978年 | 5567篇 |
1977年 | 5332篇 |
1976年 | 5504篇 |
1975年 | 5049篇 |
1974年 | 5219篇 |
1973年 | 5514篇 |
1972年 | 3484篇 |
1971年 | 2845篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
V. V. Dvorkin N. N. Dzbanovskii A. F. Pal’ N. V. Suetin A. Yu. Yur’ev P. Ya. Detkov 《Physics of the Solid State》2004,46(4):729-732
A suspension of ultrafine-dispersed nanodiamond was used for introducing (in particular, selectively) high-density centers of diamond nucleation on various substrates. High-quality doped diamond films to be used as electrochemistry electrodes were deposited from the gas phase in a microwave discharge on certain substrates treated using ultrafine-dispersed nanodiamond. A uniform distribution of nucleation centers with concentrations greater than 1010 cm-2 on silicon substrates was obtained. Electrochemical current-potential curves were measured for continuous films. Diamond meshes of different transparency were grown using selective nucleation. Successful production of high-quality doped diamond meshes gives grounds to consider them the most promising electrodes for use in electrochemistry. 相似文献
182.
G. Busiello R. V. Saburova V. G. Sushkova G. P. Chugunova 《Physics of the Solid State》2004,46(2):316-325
The ageing effect is studied analytically in a disordered quantum system interacting with its surroundings and subjected to an external ac magnetic field. Energy dissipation is due to the interaction of the system with a set of independent harmonic oscillators, imitating a quantum thermal bath. Dynamic equations for the autocorrelation function and linear-response function are derived using the method of closed-path integrals. The effect of an external field is studied on the correlation function and response in the spin-glass and paramagnetic phases. Both functions are found to depend on the spin interaction strength. 相似文献
183.
O. Yu. Borkovskaya N. L. Dmitruk I. B. Ermolovich R. V. Konakova V. V. Milenin 《Technical Physics》2004,49(3):325-329
The properties of nonrectifying AuGe/GaAs (Al0.4Ga0.6As) contacts exposed to heat treatment, 60Co γ radiation, and γ radiation combined with the application of an electrical bias are studied. A correlation between the
type of interfacial interaction in the contacts and their resistance is found. Results obtained are explained in terms of
a diffusion model with a movable boundary of the metal layer. 相似文献
184.
Russian Physics Journal - 相似文献
185.
186.
Results of a numerical analysis of mass transfer in systems of macroscopic particles with various isotropic interaction potentials are presented. Parameters that determine transport properties of nonideal dissipative systems are obtained for a broad class of model potentials. An approximate expression for the diffusivity of interacting particles is proposed. The relationship between diffusivity and viscosity is analyzed for strongly nonideal systems. 相似文献
187.
The method that we previously developed for going over from double volume integrals to double surface integrals in calculating the Coulomb energy of nuclei that have a sharp surface is generalized to the case of nuclei where the range of nuclear forces is finite and where the nuclear surface is diffuse. New formulas for calculating the Coulomb and the nuclear energy of deformed nuclei are obtained within this approach. For a spherically symmetric nucleus, in which case there is an analytic solution to the problem in question, the results are compared with those that are quoted in the literature, and it is shown that the respective results coincide identically. A differential formulation of the method developed previously by Krappe, Nix, and Sierk for going over from double volume integrals to double surface integrals is proposed here on the basis of the present approach. 相似文献
188.
E. A. Ekimov E. L. Gromnitskaya D. A. Mazalov A. F. Pal’ V. V. Pichugin S. Gierlotka B. Palosz J. A. Kozubowski 《Physics of the Solid State》2004,46(4):755-757
Superhard nanodiamond-SiC ceramics are prepared by infiltrating liquid Si into porous nanodiamond compacts under pressure.
Synthesized samples are 2.2 mm thick and 3–4 mm in diameter. The effect of particle size of dynamically synthesized nanodiamond
powders on silicon infiltration and SiC phase formation is studied. It is established that silicon does not penetrate into
the pores of nanodiamond powders if the original particle size is smaller than 0.5–1.0 μm. The critical pore size for infiltration
is 100–200 nm. A study of the microstructure of the samples showed the presence of the nanometer-and submicron-scale SiC phase.
The ultrasound velocities are measured in the prepared compacts, and the elastic moduli are calculated.
__________
Translated from Fizika Tverdogo Tela, Vol. 46, No. 4, 2004, pp. 734–736.
Original Russian Text Copyright ? 2004 by Ekimov, Gromnitskaya, Mazalov, Pal’, Pichugin, Gierlotka, Palosz, Kozubowski. 相似文献
189.
190.
R. G. Zakinyan 《Technical Physics》2004,49(9):1110-1115
The motion of the front of crystallization and the growth of a film at the surface of a plate are analyzed in the case of
a laminar and in the case of a turbulent flow mode. Conditions are determined under which there occurs a transition from a
matt inhomogeneous structure to a transparent homogeneous structure of ice. It is shown that, for a film to be steadily preserved
at the plate surface, the film thickness must be larger than a critical equilibrium-thickness value h
b.c, in which case a transparent homogeneous structure of ice is formed. Otherwise, the film at the plate surface is unstable
and disappears in the course of time. The icing of aircrafts is the most important application of the results obtained in
this study. 相似文献