全文获取类型
收费全文 | 199篇 |
免费 | 11篇 |
国内免费 | 1篇 |
专业分类
化学 | 135篇 |
晶体学 | 10篇 |
力学 | 10篇 |
数学 | 3篇 |
物理学 | 53篇 |
出版年
2022年 | 5篇 |
2021年 | 5篇 |
2020年 | 8篇 |
2019年 | 5篇 |
2018年 | 7篇 |
2017年 | 7篇 |
2016年 | 9篇 |
2015年 | 9篇 |
2014年 | 8篇 |
2013年 | 10篇 |
2012年 | 10篇 |
2011年 | 10篇 |
2010年 | 4篇 |
2009年 | 6篇 |
2008年 | 6篇 |
2007年 | 11篇 |
2006年 | 11篇 |
2005年 | 7篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1993年 | 2篇 |
1991年 | 2篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 6篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1969年 | 3篇 |
1966年 | 1篇 |
排序方式: 共有211条查询结果,搜索用时 93 毫秒
101.
A. S. Rogachev K. V. Kuskov D. O. Moskovskikh A. A. Usenko A. O. Orlov N. F. Shkodich M. I. Alymov A. S. Mukasyan 《Doklady Physics》2016,61(6):257-260
The results of measurement of electric resistivity and thermal conductivity of materials obtained by spark plasma sintering from powders of Cu, Cr, and their mixtures in the range of 300–600 K are presented. It is shown that the grinding of powders in planetary mills results in a reasonably substantial change in the electric and thermal properties of materials: to increasing electric resistivity and decreasing thermal conductivity and temperature coefficients of electric resistivity. The possible causes of these effects are considered. 相似文献
102.
103.
Site‐Directed Dimerization of Bowl‐Shaped Radical Anions to Form a σ‐Bonded Dibenzocorannulene Dimer
下载免费PDF全文
![点击此处可从《Angewandte Chemie (International ed. in English)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dr. Sarah N. Spisak Dr. Alexander V. Zabula Melisa Alkan Dr. Alexander S. Filatov Prof. Dr. Andrey Yu. Rogachev Prof. Dr. Marina A. Petrukhina 《Angewandte Chemie (International ed. in English)》2018,57(21):6171-6175
Designed site‐directed dimerization of the monoanion radicals of a π‐bowl in the solid state is reported. Dibenzo[a,g]corannulene (C28H14) was selected based on the asymmetry of the charge/spin localization in the C28H14.? anion. Controlled one‐electron reduction of C28H14 with Cs metal in diglyme resulted in crystallization of a new dimer, [{Cs+(diglyme)}2(C28H14?C28H14)2?] ( 1 ), as revealed by single crystal X‐ray diffraction study performed in a broad range of temperatures. The C?C bond length between two C28H14.? bowls (1.560(8) Å) measured at ?143 °C does not significantly change upon heating of the crystal to +67 °C. The single σ‐bond character of the C?C linker is confirmed by calculations. The trans‐disposition of two bowls in 1 is observed with the torsion angles around the central C?C bond of 172.3(5)° and 173.5(5)°. A systematic theoretical evaluation of dimerization pathways of C28H14.? radicals confirmed that the trans‐isomer found in 1 is energetically favored. 相似文献
104.
M. N. Sokolov A. V. Rogachev A. V. Virovets A. S. Bogomyakov 《Journal of Structural Chemistry》2018,59(1):126-130
Single crystals of Tl2[NbCl6] (1) and Tl2 [NbBr6] (2) are obtained as black needles on heating TlCl, Nb, S2Cl2 (1) and Tl, Nb, and Br2 at 400°C (2). Tl2NbBr6 also forms in the reaction of TlBr, Nb, Br2, and S at 500°C. Both compounds crystallize in the K2[PtCl6] structure type to form non-distorted octahedral [NbХ6]2– anions (Nb–Cl 2.397(4) Å and Nb–Br 2.516(2) Å). The magnetic properties of Tl2[NbBr6] in a range 5-300 K indicate an antiferromagnetic interaction between Nb4+ ion spins (d1, S = 1/2). On cooling, the compound becomes a noncollinear ferromagnet with Tc = 23 K. 相似文献
105.
106.
Andrey Yu. Rogachev Paul Jerabek Susanne Klein Gernot Frenking Roald Hoffmann 《Theoretical chemistry accounts》2012,131(3):1149
HBCBH and HAlCAlH are related electron-deficient molecules, predicted as local minima on their respective potential energy
surfaces. Different views of their electronic structure—as allenes, carbenes, or carbones—prompted two research groups to
a friendly competition exploring the predilection of these small molecules to dimerize. Many such dimers emerged from the
calculations, some with large enthalpies favoring dimerization. Most interesting among these is an octahedral didehydrocarborane
(or alane). The menagerie of (HECEH)2, E = B, Al structures obtained shows great variety in its bonding patterns. That variety is instructive, for it points to
the necessity of examining dimerization for any theoretically postulated metastable molecule. We also learn of the continuing
utility of simple Lewis structures, the acid–base reactivity of carbones and carbenes, and the dominant role of electron deficiency
in borane and alane chemistry. 相似文献
107.
O. V. Kotova S. V. Eliseeva A. S. Averjushkin L. S. Lepnev A. A. Vaschenko A. Yu. Rogachev A. G. Vitukhnovskii N. P. Kuzmina 《Russian Chemical Bulletin》2008,57(9):1880-1889
The effect of the nature of organic ligands and complex formation on the photoluminescent characteristics (relative quantum
yield, excited-state lifetime) and thermal stability of tetradentate Schiff bases (H2L), derivatives of salicylaldehyde (H2(SAL)1, H2(SAL)2), o-vanillin (H2(MO)1, H2(MO)2) with ethylenediamine and o-phenylenediamine, and their zinc(II) complexes was studied. Zinc(II) complexes were synthesized by the reaction of H2L with Zn(AcO)2·2H2O in MeOH at room temperature or under reflux. In the case of H2L = H2(SAL)2, H2(MO)1, H2(MO)2, complexes of the composition ZnL·H2O were isolated irrespective of the temperature. For H2L = H2(SAL)1, the reaction results in Zn(SAL)1·H2O at room temperature and in anhydrous dimeric complex [Zn(SAL)1]2 under reflux. Density functional calculations of H2L and ZnL confirmed that (1) luminescence of these compounds is due to the π-π* transition between orbitals of the organic
ligand and (2) enhancement of conjugation of the chain and introduction of electron-donating substituents lead to a decrease
of the energy gap and, there-fore, to a bathochromic shift of the emission maximum.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1846–1855, September, 2008. 相似文献
108.
M. A. Yarmolenko A. A. Rogachev V. E. Agabekov A. V. Rogachev V. A. Dobysh V. A. Tarasevich D. V. Tapal’skii 《Russian Journal of Applied Chemistry》2012,85(4):678-683
Morphological features and structure of thin-film composite coatings containing polyhexamethylene-guanidines and polyurethanes and prepared from volatile products of electron-beam dispersion of these polymers were studied. 相似文献
109.
110.
Rogachev A. V. Yarmolenko M. A. Rogachev A. A. Gorbachev D. L. 《Russian Journal of Applied Chemistry》2009,82(9):1655-1661
Regular trends in formation of composite polymeric coatings based on polyaniline (emeraldine base) and thermoplastic polymers
(polytetrafluoroethylene, polyurethane) from the gas phase generated by electron-beam dispersion were determined. The dependence
of the molecular structure and adsorption activity of the deposited coating on its composition at various modes of support
treatment was examined. 相似文献