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101.
为了验证对称双漏斗肥皂膜实验在肥皂膜腰部半径自动变细之前的整个过程中肥皂膜的形状始终满足最小表面能原理,采用了四对半径不同的漏斗分别进行验证,利用FastStone Capture[1]软件对每种情况下的腰部半径随漏斗间距变化关系进行测量。通过拟合理论曲线与构建四种情况下分别对应的离散点,从而验证了这样一个结论:肥皂膜的形状在稳定区以内均满足最小表面能原理。此外,为了验证大小肥皂泡连通前后的半径关系,使用简易三通管,并使用FastStone Capture软件,测量了五次独立重复实验的数据。最后得到与理论计算相比较低误差的实验结果,从而验证了大小肥皂泡连通前后满足体积相加性。 相似文献
102.
Total cross sections for electron scattering from fluoromethanes: A revised additivity rule method
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The additivity rule for electron-molecule scattering is revised by considering the difference between the free atom and the bound atom in the molecule.The total cross sections for electron scattering from fluoromethanes(CF4,CF3H,CF2H2,and CFH3) are calculated in an energy range from 100 eV to 1500 eV by the revised additivity rule.The present calculations are compared with the original additivity rule results and the available experimental data.Better agreement with each other is obtained. 相似文献
103.
Let A be a standard operator algebra on a Banach space of dimension 〉 1 and B be an arbitrary algebra over Q the field of rational numbers. Suppose that M : A → B and M^* : B → A are surjective maps such that {M(r(aM^*(x)+M^*(x)a))=r(M(a)x+xM(a)), M^*(r(M(a)x+xM(a)))=r(aM^*(x)+M^*(x)a) for all a ∈ A, x ∈ B, where r is a fixed nonzero rational number. Then both M and M^* are additive. 相似文献
104.
The nucleus-independent chemical shift (NICS)-XY-Scan is a simple and easy tool for the quantitative measurement of the aromaticity of polycyclic aromatic hydrocarbons and identification of the existence of local and global ring currents. We recently introduced an additivity scheme that uses the NICS-XY-Scans of smaller building blocks to predict the aromatic profiles of larger polycyclic aromatic hydrocarbon systems. We now report on an expansion of the methodology to include systems of varying aromatic natures containing the heteroatoms B, N, O, and S. The additivity approach allows for rapid and resource-efficient generation of NICS-XY-Scans of large, complex systems. Moreover, it reveals that the magnetic criterion of aromaticity behaves in an additive manner, and that the ring currents of multi-ring systems appear to be mostly localized within subunits of up to three rings. 相似文献
105.
106.
Yongge Tian 《Linear and Multilinear Algebra》2005,53(1):45-65
Some results on the Moore-Penrose inverse for sums of matrices under rank additivity conditions are revisited and some new consequences are presented. Their extensions to the weighted Moore-Penrose inverse of sums of matrices under rank additivity conditions are also considered. 相似文献
107.
Fumio Hiai 《Journal of multivariate analysis》1978,8(1):96-118
Set-valued measures whose values are subsets of a Banach space are studied. Some basic properties of these set-valued measures are given. Radon-Nikodym theorems for set-valued measures are established, which assert that under suitable assumptions a set-valued measure is equal (in closures) to the indefinite integral of a set-valued function with respect to a positive measure. Set-valued measures with compact convex values are particularly considered. 相似文献
108.
Let
be a probability space and a partition of . A necessary and sufficient condition is given for the existence of a -additive and measurable disintegration of P on . It is also shown that P admits a -additive (but not measurable) disintegration on whenever
is a standard space and the set (1, 2):1 and 2 are in the same element of } is coanalytic in ×. Finally, sufficient statistics (in the classical Fisherian sense) are investigated by using -additive disintegrations as conditional probabilities. 相似文献
109.
Densities and electrolytic conductances of hydrochloric acid and ternary aqueous solutions of HCl with manganese(II), copper(II), and cadmium(II) chlorides, respectively, have been measured from about 0.2 m to ternary saturation points at several constant molalities of the salt, MnCl2, or that of HCl for the system MnCl2–HCl–H2O as well as at constant total molal ionic strength of I=10.0 for all the three ternary systems (Mn, Cu, Cd)Cl2–HCl–H2O at 25°C. The molality dependence of the calculated volume of mixing changes V
m
and of the specific conductances are discussed on the basis of the different degrees of complex formation of the bivalent transition metal chlorides in the presence of excess amounts of chloride anions in the form of HCl. It was to be seen from the present results that even the manganese(II) chloride, which behaves as a fairly strong electrolyte in dilute aqueous solutions, is considerably complexed at high concentrations of HCl, with the degree of complexation of the cations increasing in the sequence Mn2–2–2–.Part of this publication was presented at the XIX International Conference on Solution Chemistry (XIX ICSC), Lund, Sweden, August 15–18, 1988. 相似文献
110.
A flow heat capcity calorimeter and a flow vibrating tube densimeter have been used to measure the apparent molal heat capacities and volumes of benzene and 25 polar compounds in methanol at 25°C. These quantities have been extrapolated to infinite dilution to obtain the standard partial molal heat capacities and volumes. The
and
data have been used in conjunction with an additivity scheme previously determined for alkanes. Group contributions were evaluatd for –OH, –NH2, –COOH, –C6H5, C=O, –COO–, –CONH–, –O–, –S–, and –S2–. The concentration dependences of cp and v of nonelectrolytes in methanol are qualitatively similar but much smaller than in water. 相似文献