全文获取类型
收费全文 | 88篇 |
免费 | 2篇 |
国内免费 | 1篇 |
专业分类
化学 | 55篇 |
晶体学 | 1篇 |
力学 | 3篇 |
数学 | 12篇 |
物理学 | 20篇 |
出版年
2023年 | 1篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 2篇 |
2012年 | 2篇 |
2011年 | 5篇 |
2010年 | 2篇 |
2009年 | 2篇 |
2008年 | 2篇 |
2007年 | 2篇 |
2006年 | 4篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1998年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1982年 | 3篇 |
1979年 | 2篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1970年 | 2篇 |
1967年 | 2篇 |
1966年 | 1篇 |
1965年 | 2篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1943年 | 1篇 |
排序方式: 共有91条查询结果,搜索用时 140 毫秒
1.
CV Tomy D Pal SS Banerjee S Ramakrishnan AK Grover S Bhattacharya MJ Higgins G Balakrishnan McK Paul 《Pramana》2002,58(5-6):925-935
The weakly pinned single crystals of the hexagonal 2H-NbSe2 compound have emerged as prototypes for determining and characterizing the phase boundaries of the possible order-disorder
transformations in the vortex matter. We present here a status report based on the ac and dc magnetization measurements of
the peak effect phenomenon in three crystals of 2H-NbSe2, in which the critical current densities vary over two orders of magnitude. We sketch the generic vortex phase diagram of
a weakly pinned superconductor, which also utilizes theoretical proposals. We also establish the connection between the metastability
effects and pinning. 相似文献
2.
Ion-selective electrodes based on the neutral carrier, 12-crown-4, in a poly(vinyl chloride) matrix were found to respond ideally, or almost ideally, to potassium, sodium, barium, strontium, magnesium, cobalt(II), nickel(II) and aluminum ions. The electrode showed good selectivity for Al3+ over Co2+ and Mg2+, and for Co2+ over Mg2+. Little selectivity was found for the other ions tested. 相似文献
3.
4.
Neutralization probabilities are presented for hyperthermal energy Na+ ions scattered from a Cu(001) crystal as a function of surface temperature and scattered velocity. A large enhancement in neutralization is observed as the temperature is increased. Velocity-dependent charge transfer regimes are probed by varying the incident energy, with the most prominent surface temperature effects occurring at the lowest energies. The data agree well with results obtained from a model based on the Newns-Anderson Hamiltonian, where the effects of both temperature and velocity are incorporated. 相似文献
5.
In subnormal glow discharge under d.c. excitation at different pressure in a varying transverse magnetic field (0 to 30 G)
some measurements have been carried out for various initial average tube currents. The voltage across the discharge increases
and average tube current and residual current decreases in the magnetic field. With the help of Beckman’s expression [4] for
the axial field and the electron density distribution in a transverse magnetic field the observed variation of current and
voltage can be satisfactorily explained. The variation of axial electric field with transverse magnetic field can be represented
to a fair degree of accuracy by the derived equation. The behaviour of residual current with magnetic field has been observed
in these oscillations. 相似文献
6.
An integral equation formulation for buoyancy-driven convection problems is developed and illustrated. Buoyancy-driven convection in a bounded cylindrical geometry with a free surface is studied for a range of aspect ratios and Nusselt numbers. The critical Rayleigh number, the nature of the cellular motion, and the heat transfer enhancement are computed using linear theory. Green's functions are used to convert the linear problem into linear Fredholm integral equations. Theorems are proved which establish the properties of the eigenvalues and eigenfunctions of the linear integral operator which appears in these equations. 相似文献
7.
Hampton MA Plackowski C Nguyen AV 《Langmuir : the ACS journal of surfaces and colloids》2011,27(7):4190-4201
The surface oxidation of sulfide minerals, such as galena (PbS), in aqueous solutions is of critical importance in a number of applications. A comprehensive understanding of the formation of oxidation species at the galena surface is still lacking. Much controversy over the nature of these oxidation products exists. A number of oxidation pathways have been proposed, and experimental evidence for the formation of elemental sulfur, metal polysulfides, and metal-deficient lead sulfides in acidic conditions has been shown and argued. This paper provides further insight into the electrochemical behavior of galena at pH 4.5. Utilizing a novel experimental system that combines in situ electrochemical control and AC mode atomic force microscopy (AFM) surface imaging, the formation and growth of nanoscopic domains on the galena surface are detected and examined at anodic potentials. AFM phase images indicate that these domains have different material properties to the underlying galena. Continued oxidation results in nanoscopic pitting and the formation of microscopic surface domains, which are confirmed to be elemental sulfur by Raman spectroscopy. Further clarification of the presence of elemental sulfur is provided by Cryo-XPS. Polysulfide and metal-deficient sulfide could not be detected within this system. 相似文献
8.
Richard R. Hampton 《Communications in Mathematical Physics》1979,67(3):187-197
A generalization of graph theory is introduced and used to obtain Feynman parametric formulas relevant to renormalized amplitudes. The generalization of graph theory is based upon circuit coefficients instead of the usual incidence matrix. The parametric formulas presented are valid for amplitudes which have been renormalized, as in the Zimmermann formulation, by subtracting Taylor terms in momentum space.The research reported in this paper was supported in part by the Max-Planck-Institut für Physik, München, by the German and American Fulbright Commission in Bonn, and by the Department of Mathematics of the University of Virginia, Charlottesville. 相似文献
9.
10.