全文获取类型
收费全文 | 62篇 |
免费 | 3篇 |
国内免费 | 9篇 |
专业分类
化学 | 45篇 |
力学 | 3篇 |
数学 | 15篇 |
物理学 | 11篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2017年 | 1篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 3篇 |
2012年 | 2篇 |
2011年 | 3篇 |
2010年 | 5篇 |
2009年 | 2篇 |
2008年 | 2篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 4篇 |
2001年 | 3篇 |
2000年 | 6篇 |
1999年 | 3篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1982年 | 1篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1976年 | 4篇 |
1975年 | 4篇 |
1970年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有74条查询结果,搜索用时 31 毫秒
1.
Spectrophotometric investigation of the reaction of eriochrome cyanin RC and magnesium and aluminium
The reaction of magnesium or aluminium ions with Eriochrome Cyanin RC in alkaline medium leads to formation of a complex of type ML. The molar absorptivities of the complexes are 1.90 +/- 0.14 x 10(3)1. mole(-1).cm(-1) at 570 nm for the magnesium complex and 3.87 +/- 0.04 x 10(4) at 555 nm for the aluminium complex. The conditional stability constants of the complexes were determined at various pH values, and hence the overall formation constants, which were found to be log beta(111) = 8.65 +/- 0.06 for MgOHL, log beta(121) = 22.29 +/- 0.05 for AlH(2)L, log beta(111) = 18.25 +/- 0.14 for AlHL, and log beta(101) = 13.66 +/- 0.01 for AlL. 相似文献
2.
A simple and sensitive polarographic method for determining arsenic in steel is presented. The steel is dissolved in HNO(3), and arsenic reduced with Na(2)S(2)O(5)-K.I. The polarographic wave is recorded for an electrolyte at pH 3.0 and containing Fe(II), Mn(II). citric and ascorbic acids. Levels of 0.2% and 0.003% As can be determined with a coefficient of variation of +/- 6%. 相似文献
3.
The article describes a general treatment of voltammetry of equilibrium complexation reactions at an electrode expanding in accord with any power law, the stationary electrode and the dropping mercury electrode being special cases. Reversible, irreversible and quasireversible electrode reactions are embraced by the treatment. A general expression for the current—voltage characteristic was derived, which was applied to the case of the polarographic reduction of complex ion, where either the simple or complex ion is electrochemically active. An equation accounting for the surface concentration of all reacting species is derived, the solution of which under appropriate conditions gives the equations of Lingane, Matsuda and Ayabe, etc. Correlations of potential, current and wave shape with complexing agent concentration are presented and discussed. A criterion for the splitting of the polarographic wave in the absence of excess of the complexing agent is proposed. Experimental results of several papers are discussed in the light of these criteria and a satisfactory agreement between the results and the predictions is established. 相似文献
4.
The boron atom in C22H15BO5 is O,O’-chelated by the anions in a tetrahedral geometry, with the planar five-and six-membered chelate rings being orthogonal to each other. The molecule lies on a two-fold rotation axis. The molecule is disordered with respect to another molecule in a 93:7 ratio; the treatment of the ‘whole-molecule disorder’ by employing a large number of restraints is described. Crystal data: C22H15BO5, monoclinic C2/c, a = 17.1804(5), b = 12.9409(4), c = 9.8842(3) , β = 124.832(2)o, V = 1803.82(9) 3 at –173 K. 相似文献
5.
6.
A general formulation of the nonlinear filtering problem inRiemanman manifolds is given by use of the strong solutionsof the stochastic differential equations for the state and observationprocesses in the orthonormal frame bundles of the state andobservation process manifolds, respectively. A general Bayesformula for the conditional expectation of smooth functionsof the state process is given. This is used to give a directderivation of the Zakai equation for the general problem underconsideration. An example is presented. 相似文献
7.
8.
The article describes a general treatment of the catalytic reaction mechanism at an electrode expanding in accord with any power law, the stationary electrode and the dropping mercury electrode being special cases. Reversible, irreversible and quasi-reversible electrode reactions are embraced by the treatment. A general expression for the current-voltage characteristic was derived, which was applied to different electrolysis regimes. The cases when the regeneration reaction will influence the catalytic wave characteristics are also discussed. 相似文献
9.
We obtain rigidity results on arbitrary proper holomorphic maps F from an irreducible bounded symmetric domain Ω of rank ≥2 into any complex space Z. After lifting to the normalization of the subvariety F (Ω) Z, we prove that F must be the canonical projection map to the quotient space of Ω by a finite group of automorphisms. The approach is along the line of the works of Mok and Tsai by considering radial limits of bounded holomorphic functions derived from F and proving that proper holomorphic maps between bounded symmetric domains preserve certain totally geodesic subdomains. In contrast to the previous works, in general we have to deal with multivalent holomorphic maps for which Fatou’s theorem cannot be applied directly. We bypass the difficulty by devising a limiting process for taking radial limits of correspondences arising from proper holomorphic maps and by elementary estimates allowing us to define distinct univalent branches of the underlying multivalent map on certain subsets. As a consequence of our rigidity result, with the exception of Type-IV domains, any proper holomorphic map f : Ω→ D of Ω onto a bounded convex domain D is necessarily a biholomorphism. In the exceptional case where Ω is a Type-IV domain, either f is a biholomorphism or it is a double cover branched over a totally geodesic submanifold which can be explicitly described. 相似文献
10.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献