全文获取类型
收费全文 | 61篇 |
免费 | 2篇 |
国内免费 | 1篇 |
专业分类
化学 | 32篇 |
力学 | 2篇 |
数学 | 3篇 |
物理学 | 27篇 |
出版年
2022年 | 2篇 |
2020年 | 1篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2012年 | 1篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2009年 | 2篇 |
2008年 | 2篇 |
2007年 | 3篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 3篇 |
2002年 | 8篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1968年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有64条查询结果,搜索用时 218 毫秒
31.
We have studied the peak effect (PE) phenomenon in single crystals of weakly pinned superconductors CeRu2 and 2H-NbS2. 2H-NbS2 is iso-structural and iso-electronic to 2H-NbSe2, whose similarity with CeRu2 as regards the PE representing the order-to-disorder transformation of the flux line lattice was claimed some time ago. We
report on the step change in equilibrium magnetization across the peak effect in CeRu2. We also present the vortex phase diagram of 2H-NbS2 obtained from the magnetization data, and compare the PE phenomenon in 2H-NbS2 and 2H-NbSe2. 相似文献
32.
For ions and polar molecules located near a surface, we derived and analyzed the general formulas to calculate their solvation
energies.
St. Petersburg State University. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 6, pp. 3–12, November-December, 1994.
Translated by A. Arbuznikov 相似文献
33.
Olav Vahtras Hans rgren Hans Jrgen AA. Jensen 《Journal of computational chemistry》1994,15(6):573-579
The evaluation of gradient vectors of a general operator with one-index, double-one-index, or higher-order one-index transformed integrals is a key operation in multiconfiguration response theory calculations. We describe an integral-driven direct algorithm that carries out this operation efficiently without pretransforming the integrals. The use of this algorithm leads to a considerable reduction in disk space and timing. © 1994 by John Wiley & Sons, Inc. 相似文献
34.
35.
A new series of 6,8-dibromo-2-(4-chlorophenyl)quinazolin-4(3H)-one derivatives VI–XIII were synthesized. Their chemical structures were confirmed by spectral and elemental analysis. The cytotoxic effect of the newly synthesized compounds was tested in vitro against human breast cancer cell line (MCF-7). Most of the tested compounds have shown promising cytotoxic activity. Compounds X and XIIIb exerted a powerful cytotoxic effect against MCF-7 with a very low IC50 (0.0015 and 0.0047 µmol/ml), while compounds VI, VII, VIII, XIIb, XI, XIIIc and IX exerted a moderate cytotoxic effect (IC50 0.01523, 0.0213, 0.031, 0.0478, 0.049, 0.068 and 0.079 µmol/ml respectively), compared to doxorubicin (0.0025 µmol/ml). Exploring their apoptotic effect; interestingly,all compounds activated apoptotic cascade in MCF-7. Compounds VI, XIIIb, XIIb, XI, XIIa, VII, V and VIII showed potent effect even much more than doxorubicin by 12.87–5.91 folds, while compounds XIIIc, IX, XIIIa, XIIc and X showed moderate increase in CASP3 activity by 4.96–3.22 folds relative to untreated cells more or less similar to doxorubicin (5.57 folds). 相似文献
36.
Obliquely propagating altra-low-frequency dust-electromagnetic waves in a self-gravitating, warm, magnetized, two fluid dusty
plasma system have been investigated. Two special cases, namely, dust-Alfvén mode propagating parallel to the external magnetic
field and dustmagnetosonic mode propagating perpendicular to the external magnetic field have also been considered. It has
been shown that effects of self-gravitational field, dust fluid temperature, and obliqueness significantly modify the dispersion
properties of these ultra-low-frequency dust-electromagnetic modes. It is also found that in parallel propagating dust-Alfvén
mode these effects play no role, but in obliquely propagating dust-Alfvén mode or perpendicular propagating dust-magnetosonic
mode the effect of self-gravitational field plays destabilizing role whereas the effect of dust/ion fluid temperature plays
stabilizing role. 相似文献
37.
It is shown how one can transform scalar first-order ordinarydifferential equations which admit non-local symmetries of theexponential type to integrable equations admitting canonicalexponential non-local symmetries. As examples we invoke theAbel equation of the second kind, the Riccati equation and naturalgeneralizations of these. Moreover, our method describes howa double reduction of order for a second-order ordinary differentialequation which admits a two-dimensional Lie algebra of generatorsof point symmetries can be affected if the second-order equationis first reduced in order once by a symmetry which does notspan an ideal of the two-dimensional Lie algebra. 相似文献
38.
39.
A method for solving the vibrational problem by using an effective energy operator containing Morse potentials and new model
atom approximations is developed. The approach is explained by reference to the trifluoromethylacetylene molecule where the
model atom is a CCC or CC atomic group. Using certain assumptions for parameters in the spectrum, we managed to confirm the
known experimental result of bond strengthening of the terminal hydrogen atom when the CC bond order increases and to predict
the CH bond energy (462.5±4.6 kJ/mole). This procedure seems to be also effective for more complex adsorption problems where
the model atom is a crystal. Given that the surface effect is predicted by the parameters of the method, the corresponding
model energy operator is constructed. With appropriate spectral data, the approach guarantees very accurate estimations of
adsorption bond energies.
Translated from Zhumal Struktumoi Khimii, Vol. 38, No. 2, pp. 263–269, March–April, 1997. 相似文献
40.
Optics and Spectroscopy - The change in the vibration spectrum of an iron [Fe(OH)2(H2O)2]+ hydroxo cation during its interaction with peroxynitrite [NO–O2]? in an aqueous medium... 相似文献