全文获取类型
收费全文 | 543篇 |
免费 | 18篇 |
国内免费 | 20篇 |
专业分类
化学 | 193篇 |
晶体学 | 45篇 |
力学 | 6篇 |
数学 | 48篇 |
物理学 | 289篇 |
出版年
2023年 | 1篇 |
2022年 | 9篇 |
2021年 | 14篇 |
2020年 | 19篇 |
2019年 | 17篇 |
2018年 | 29篇 |
2017年 | 19篇 |
2016年 | 25篇 |
2015年 | 12篇 |
2014年 | 22篇 |
2013年 | 26篇 |
2012年 | 25篇 |
2011年 | 34篇 |
2010年 | 22篇 |
2009年 | 25篇 |
2008年 | 24篇 |
2007年 | 28篇 |
2006年 | 14篇 |
2005年 | 21篇 |
2004年 | 31篇 |
2003年 | 20篇 |
2002年 | 20篇 |
2001年 | 20篇 |
2000年 | 24篇 |
1999年 | 15篇 |
1998年 | 2篇 |
1997年 | 9篇 |
1996年 | 8篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 5篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1982年 | 4篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
排序方式: 共有581条查询结果,搜索用时 15 毫秒
81.
We used Monte Carlo method to generate the configurations of disassembly of hot nucleus Au* based on the Atomic Mass Table and the conservation of mass and charge number.The resulted charge distribution of fragments was then used to calculate the conditional moments.The logarithm correlation between second and third moments of experimental charge distribution is very well reproduced by theory.It seems that no connection to the critical phenomenon of concerned system exists. 相似文献
82.
In this paper a simplified method for the calculation of average Coulomb energy in statistical model of the disassembly processes of hot nuclei is proposed.The effect of freeze-out volume is studied based on the assumption of Gaussion-like distribution.It is indecated that the centre and dispersion of Gaussion-like distribution somewhat reflect the location and the renge of liquid-gas coexistence phase. 相似文献
83.
THE EVIDENCE OF DECONFINEMENT PHASE TRANSITION OF SU(2) LATTICE GAUGE MODEL BY MONTE CARLO METHOD
下载免费PDF全文
![点击此处可从《中国物理C(英文版)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
In this paper,we have calculated the SU(2) lattice gauge by the Monte Carlo method.For the finite temperature problem 83×4 lattice is used and for the zero temperature problem 84 lattice.From the calculations of the energy density,heat capacity and entropy density,the results indicate that there is a deconfinement phase transition when T/ΛL=40—50. 相似文献
84.
M. V. Patrakeev I. A. Leonidov E. B. Mitberg A. A. Lakhtin V. G. Vasiliev V. L. Kozhevnikov K. R. Poeppelmeier 《Ionics》1999,5(5-6):444-449
The equilibrium oxygen content was measured in the model system and important oxygen permeable material La1−xSrxCoO3−δ, where x=0.6, in the temperature range 650–900 °C and oxygen partial pressure range between 10−5 and 1 atm. The data were utilized to obtain changes in the partial entropy and enthalpy of oxygen in the solid as a function
of the oxygen content. It is shown that the initially cubic perovskite undergoes to a phase transition to a tetragonal structure
at δ >0.3. The oxygen permeation of L0.4Sr0.6CoO3−δ at 700–900 °C is found to be controlled by bulk solid state processes. The activation energy equals about 0.8 eV at high
oxygen pressure and small oxygen nonstoichiometry. Increasing oxygen deficiency results in a rapid increase in the activation
energy. In combination with thermodynamic data, these changes can be explained as resulting from the intrinsic spatial inhomogeneouty
in oxygen vacancy distribution which varies both with temperature and oxygen nonstoichiometry. It is shown that, when the
oxygen deficiency increases at constant temperature, the oxygen vacancies form locally ordered microdomains (clusters), which
eventually results in a transition of the cubic perovskite structure to the tetragonal structure. The oxygen ion conductivity
depends strongly on the development of the ordering.
Paper presented at the 6th Euroconference on Solid state Ionics, Cetraro, Calabria, Italy, Sept. 12–19, 1999. 相似文献
85.
The distributions of dynamic variables in the deep inelastic scattering (DIS) of heavy-ions are studied by a direct simulation technique based on the single-nucleon-transfer-mechanism. The relative motion of the two collision partners is described by a Lagrange equation, and the transition probability of a single nucleon during the interaction time is calculated by the statisti-cal spectroscopy method.The occurrence of the transition event and the corresponding change of the dynamic variables are both treated randomly according to the transition probability. The calculated results for the reaction of 40Ar+58Ni(EL=280MeV) are compared with experimental data. 相似文献
86.
Exploration for Degradation of Λ Polarization Produced in Relativistic Nucleus Nucleus Collisions
下载免费PDF全文
![点击此处可从《中国物理C(英文版)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
YE YunXiu CHEN Zhi RUAN TuNan SHEN Ji LV HaiJiang DONG WeiJiang SA BenHao TAI An 《中国物理C(英文版)》2000,24(2):125-130
The degradation of Λ transverse polarization produced in S+Pb central collisions at energy 200 GeV per nucleon has been studied in detail. The S+Pb central collision events have been generated using Monte-Carlo generator——LUCIAE at 200 GeV per nucleon. The various factors degrading Λ transverse polarization have been analysed quantitatively. The ratios of Λ′s produced from rescattering, secondary production and decays of Σ, Ξ hyperons to the total measurable Λ′s in experiment have been investigeted and the degradation effect of these Λ on the total polarization has been determined. The simulation and calculation show that above three factors decrease the Λ transverse polarization strongly, however, can not eliminate the polarization completely when the Λ′s are assumed to be produced from hadronic gas in the final state. To explan the experimental data of vanished Λ polarization, it probably needs to consider new mechanisms of Λ production, including a weak effect of QGP formation. 相似文献
87.
88.
Evgeny A. Lisin Evgeny A. Kononov Eduard A. Sametov Mikhail M. Vasiliev Oleg F. Petrov 《Molecules (Basel, Switzerland)》2021,26(24)
Stability of a vertically aligned microparticle pair in a stratified glow DC discharge is experimentally investigated. Using laser perturbations, it is shown that, for the same discharge parameters, a pair of microparticles can be suspended in two stable configurations: vertical and horizontal. The interparticle interaction and the electric field of the stratum in the region of particle levitation are quantitatively investigated for the first time. The decharging effect of the lower (downstream) particle by the ion flow wake is also observed for the first time in a glow discharge. The obtained experimental data made it possible to check the analytical criteria for the configurational stability of the system. 相似文献
89.
Alexander D. Vasiliev Alexander M. Astachov Maxim S. Molokeev Ludmila A. Kruglyakova Rudolf S. Stepanov 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(9):o499-o501
The molecule of the title compound, C3H5N5O4, has a planar geometry. Due to the presence of a second nitro group, the lengths of the two conjugated C—N bonds are different. Nevertheless, the conjugation of the nitrimine group spreads to the nitramine group. Intermolecular N—H...O bonds connect molecules into dimers in the crystal structure. 相似文献
90.
Alexander D. Vasiliev Alexander M. Astachov Maxim S. Molokeev Ludmila A. Kruglyakova Rudolf S. Stepanov 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):o550-o552
The title compound, CH3N5O4, is almost planar, and the conformation is fixed by two intramolecular N—H⋯O hydrogen bonds. Owing to the delocalization of π‐electron density over the whole molecule, there is through‐conjugation, with the C—N, N—N and N—O bond lengths having values intermediate between those typical for the corresponding single and double bonds. 相似文献