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11.
S. L. Khursan V. V. Shereshovets A. F. Khalizov A. I. Voloshin V. D. Komissarov V. P. Kazakov 《Reaction Kinetics and Catalysis Letters》1993,51(2):389-392
Thermolysis of di-(tert-butyl)-trioxide produces IR and visible chemiluminescence (CL) which may be ascribed to emission by singlet oxygen (IR-CL) and triplet acetone (vis. CL). 相似文献
12.
D. V. Kazakov A. I. Voloshin N. N. Kabal'nova V. V. Shereshovets V. P. Kazakov 《Russian Chemical Bulletin》1997,46(6):1089-1093
The reaction of dimethyldioxirane (1) with the RuII trisbipyridyl complex accompanied by chemiluminescence (CL) was studied. It is established that the intensity of CL and the
rate of its decay increase proportionally with the concentration of RuII. The bimolecular rate constant (k
2) of the reaction of1 with RuII was determined. The activation parameters (E
a and logA) for this reaction were calculated from the temperature dependence ofk
2. The excitation yield of RuII* (η
Ru
*
) was estimated. The quenching of RuII* by dioxirane was studied, and the bimolecular quenching constant and the coefficient of excitation regeneration were determined.
It was suggested that the catalysis of the decomposition of1 and the excitation of RuII occurvia a mechanism of chemically initiated electron exchange.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1138–1142, June, 1997. 相似文献
13.
D. V. Kazakov D. R. Khusnullina N. N. Kabal'nova S. L. Khursan V. V. Shereshovets 《Russian Chemical Bulletin》1997,46(10):1690-1693
The kinetics of the reaction between dimethyldioxirane and 2-methylbutane in acetone solutions were studied spectrophotometrically
at 25 °C. The radical-chain induced decomposition of dioxirane proceeding with the participation of the carbon-centered radicals
follows the first-order kinetic law. The reaction is inhibited by dioxygen. In the presence of O2, the dimethyldioxirane consumption is due to the homolysis of the O−O bond (at a rate constant of 6.3·10−4 s−1) followed by attack of the C−H bond of 2-methylbutane by the biradical formed. The rate constant of the reaction between
the alkyl radical and dimethyldioxirane was estimated.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1785–1788, October, 1997. 相似文献
14.
V. P. Kazakov A. I. Voloshin S. S. Ostakhov N. Sh. Ableeva 《Russian Chemical Bulletin》1995,44(3):432-436
The thermal decomposition of dispiro(1,2-dioxetane-diadamantane) (1) sorbed on silipore containing EuCl3 ando-phenanthroline was investigated. The observed chemiluminescence is caused by radiative deactivation of EU*(iii) formed according to an energy transfer mechanism. Chemiluminescence decay in the course of the decomposition of1 is exponential with the rate constantk. The activation parameters of the decomposition of1 sorbed on silipore were determined from the temperature dependence ofk. These parameters are independent of the Eu(iii) content. A kinetic compensating effect was found: the dependence of logA onE
a as a function of the content of1. The mechanism of the compensating effect is discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 447–451, March, 1995. 相似文献
15.
Usachev N. Ya. Belanova E. P. Krukovsky I. M. Kanaev S. A. Atal"yan O. K. Kazakov A. V. 《Russian Chemical Bulletin》2003,52(9):1940-1949
Thermal transformations in systems formed by interaction of Zn and Na nitrates with Y, X, and A zeolites were studied by TG—DTA technique. Temperature regions of existence of adsorbed water, water of crystallization, and decomposition of NO3
– anion were determined. These intervals depend on the composition, structure, method of preparation, and pre-treatment conditions of zeolite systems. The extent of NO3
– decomposition depends not only on the zinc and sodium content but also on the presence of ammonia involved in NO3
– reduction. The zeolite matrix strongly stabilizes the occluded NO3
– anions. A portion of zinc oxide formed by zinc nitrate decomposition is probably localized inside the zeolite cavities as the [Zn—O—(ZnO)
n
—Zn]2+ particles. The latter compensate charges of the isolated [AlO4]– tetrahedra. 相似文献
16.
17.
V. P. Kazakov S. V. Lotnik V. N. Korobeinikova V. M. Kalinina L. A. Khamidullina R. G. Bulgakov A. N. Petrov 《Russian Chemical Bulletin》1991,40(8):1720-1720
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, p. 1934, August, 1991. 相似文献
18.
E. M. Belova N. G. Vais V. F. Sopin A. I. Kazakov Yu. I. Rubtsov G. B. Manelis G. N. Marchenko 《Russian Chemical Bulletin》1989,38(11):2244-2249
Complexing in the HNO3-CH2Cl2 system was confirmed tensimetrically. The kinetics of nitration of wood cellulose by the HNO3-CH2Cl2 mixture were investigated. A large part of the cellulose is nitrated in a first fast reaction in comparison to the HNO3-H2SO4 mixture with the same concentration of HNO3. The rate of the process is determined by the rate of diffusion of the HNO3, the rate of the process decreases more rapidly in the case of HNO3-CH2Cl2 than in the HNO3-H2SO4 mixture, which is probably due to the effect of CH2Cl2 on the diffusion coefficient of HNO3.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2445–2450, November, 1989. 相似文献
19.
The complex formation of alicyclic ketones, viz., camphor, cyclohexanone, menthone, and cytisine, with the Eu(fod)3 chelate (fod is 7,7-dimethyl-1,1,1,2,2,3,3-heptafluorooctane-4,5-dione) in the ground and excited states was studied by chemiluminescence and kinetic luminescence spectroscopy, respectively. The stability constants and thermodynamic parameters of complex formation were determined. An increase in the stability of the electron-excited complexes [Eu(fod)3*·Ketone] is explained by the enhancement of the acceptor ability of the Eu3+ chelate due to an increase in the fraction of the covalent component caused by the involvement of 4f-orbitals. The results obtained give direct evidence for the effect of the 4f-shell excitation of Eu(fod)3 on complex formation due to the involvement of f-electrons in the chemical bonds. 相似文献
20.
The processes of complexation and solvation in the Tb(ClO4)3 · nH2O –adamantylideneadamantane-1,2-dioxetane (I)–benzophenone (II) system in acetonitrile solutions were studied at 280–320 K. The complexation of Tb(ClO4)3 · nH2O in ground and electronically excited states with I and II was found out. An anomalous increase in the lifetime of Tb(ClO4)*
3 · nH2O with temperature was observed; this anomalous increase is indicative of a structural change in the environment of the terbium ion in solution. It was found that of Tb(III)* increased because of rearrangement of the inner sphere of solvation aqua complexes toward the replacement of H2O molecules by solvent molecules that exhibit a lower quenching ability. 相似文献