全文获取类型
收费全文 | 230587篇 |
免费 | 2775篇 |
国内免费 | 1498篇 |
专业分类
化学 | 122727篇 |
晶体学 | 3228篇 |
力学 | 8888篇 |
综合类 | 61篇 |
数学 | 24365篇 |
物理学 | 65676篇 |
综合类 | 9915篇 |
出版年
2019年 | 1916篇 |
2018年 | 2524篇 |
2017年 | 2572篇 |
2016年 | 3690篇 |
2015年 | 2496篇 |
2014年 | 3642篇 |
2013年 | 9059篇 |
2012年 | 8084篇 |
2011年 | 9834篇 |
2010年 | 6951篇 |
2009年 | 6698篇 |
2008年 | 9184篇 |
2007年 | 9397篇 |
2006年 | 8877篇 |
2005年 | 8109篇 |
2004年 | 7138篇 |
2003年 | 6254篇 |
2002年 | 6215篇 |
2001年 | 7077篇 |
2000年 | 5463篇 |
1999年 | 3914篇 |
1998年 | 3082篇 |
1997年 | 3030篇 |
1996年 | 3029篇 |
1995年 | 2631篇 |
1994年 | 2725篇 |
1993年 | 2589篇 |
1992年 | 2979篇 |
1991年 | 3054篇 |
1990年 | 2868篇 |
1989年 | 2762篇 |
1988年 | 2675篇 |
1987年 | 2664篇 |
1986年 | 2634篇 |
1985年 | 3427篇 |
1984年 | 3466篇 |
1983年 | 2894篇 |
1982年 | 3110篇 |
1981年 | 2861篇 |
1980年 | 2677篇 |
1979年 | 2922篇 |
1978年 | 3143篇 |
1977年 | 3143篇 |
1976年 | 3167篇 |
1975年 | 2900篇 |
1974年 | 3096篇 |
1973年 | 3042篇 |
1972年 | 2389篇 |
1971年 | 1978篇 |
1970年 | 1903篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
L. B. Beinenson 《Journal of Mathematical Sciences》2005,129(2):3730-3756
For an arbitrary poset H and measure ρ on H × R (where R is the real axis), we construct a monotone decreasing stochastic field ηρ and compute its finite-dimensional distributions. In the case where H is a Λ-semilattice and the measure ρ satisfies additional conditions, we compute various characteristics of the field ηρ such as the expectation of the field value at a point, variance of the field value at a point, and correlation function of the field. The described construction of random fields gives a new method for constructing positive definite functions on posets. Bibliography: 6 titles.__________Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 301, 2003, pp. 92–143. 相似文献
103.
I. A. Uspenskaya Z. S. Vakhovskaya M. M. Efremova M. L. Kovba A. L. Emelina Zh. V. Dobrokhotova Yu. V. Goryushkina L. A. Tiflova A. A. Popova A. S. Monaenkova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(4):529-534
The thermodynamic properties of the Ln2BaO4 phases (Ln = Dy, Ho, Sm) were studied by the electromotive force method with a fluoride electrolyte (890–1180 K), solution calorimetry in 1.07 N hydrochloric acid at 298.15 K, and differential scanning calorimetry (298–860 K). The experimental data were jointly processed, and the thermodynamic functions of the compounds over the temperature range 298–1200 K were calculated. 相似文献
104.
NAFTALIN L 《Nature》1948,161(4098):763
105.
Yu. A. Kumzerov L. S. Parfen’eva I. A. Smirnov H. Misiorek J. Mucha A. Jezowski 《Physics of the Solid State》2003,45(1):57-60
The thermal conductivity of crystalline chrysotile asbestos made up of hollow tubular Mg3Si2O5(OH)4 filaments is measured in the range 5–300 K. The paper discusses the possibility of using this material in studies of the thermal conductivity of thin filaments of metals and semiconductors incorporated into the channels of crystalline chrysotile asbestos tubes. 相似文献
106.
V. Bradnova M. M. Chernyavsky L. Just S. P. Kharlamov A. D. Kovalenko M. Haiduc K. A. Kotel’nikov V. A. Krasnov V. G. Larionova F. G. Lepekhin A. I. Malakhov G. I. Orlova N. G. Peresadko N. G. Polukhina P. A. Rukoyatkin V. V. Rusakova N. A. Salmanova B. B. Simonov S. Vokal P. I. Zarubin 《Physics of Atomic Nuclei》2003,66(9):1646-1650
A physical program of irradiation of emulsions in beams of relativistic nuclei named the BECQUEREL Project is reviewed. It is destined to study in detail the processes of relativistic fragmentation of light radioactive and stable nuclei. The expected results would make it possible to answer some topical questions concerning the cluster structure of light nuclei. Owing to the best spatial resolution, the nuclear emulsions would enable one to obtain unique and evident results. The most important irradiations will be performed in the secondary beams of He, Be, B, C, and N radioactive nuclei formed on the basis of JINR Nuclotron beams of stable nuclei. We present results on the charged state topology of relativistic fragmentation of the 10B nucleus at low energy-momentum transfers as the first step of the research. 相似文献
107.
A group representation of radiation propagation in an anisotropic medium is developed. The system of wave equations for electromagnetic potentials, obtained from the Maxwell equations with account for the constitutive equations, has been factorized. It is shown that the linear differential operator of the factorized system is orthogonal in transparent crystals and unitary in gyrotropic ones and is represented through the momentum operator. On the basis of the commutation relations for the components of this operator, the eigenvalue problem has been solved and the expression for the change in the radiant energy in the crystal in the form of spherical waves has been obtained. The dependences of the ray and phase velocities and the polarization vectors of waves on the birefringence anisotropy and gyrotropy as well as on the angular momentum, displacement current, and bound charge determining them have been analyzed. It has been established that in the general case of gyrotropic crystals where the nonreciprocity phenomenon takes place and in magnetoelectrics Maxwell equations are represented in a form similar to the Dirac equations and the electromagnetic radiation is correctly described by means of bispinors and is quantized as fermions. 相似文献
108.
109.
110.