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1.
L. I. Guseva G. S. Tikhomirova N. N. Dogadkin 《Journal of Radioanalytical and Nuclear Chemistry》2004,260(1):167-172
A simple and effective method has been developed for the continuous production of the short-lived isotope Pb as a homolog
of element 114 on the principle of a radionuclide generator. The method is based on the initial sorption of 227Ac or 223Ra on a small cation-exchange column, with subsequent “milking” of 211Pb (36.1 m) by a mixture of HCl/CH3OH. The optimum conditions for the repeated separation of 211Pb from radionuclides strongly sorbed by the cation-exchanger (Ac, Th, Ra, Pu, TPE) have been determined. Possibilities of
using the 211Pb generator for test experiments on the solution chemistry of element 114 have been shown. Advantages of aqueous alcohol
HCl solutions for the isolation of 211Pb (element 114) are discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
2.
S. A. Shiryaev M. V. Atamanov M. I. Guseva Yu. V. Martynenko A. V. Mitin V. S. Mitin P. G. Moskovkin 《Technical Physics》2002,47(2):238-243
It is suggested to produce metal-carbon composite coatings by magnetron sputtering of mosaic cathodes, which are Group IV,
V, and VI metals. The mosaic structure of the cathode elements are computer-optimized for each of the metals. Reflection electron
diffraction studies show that the coatings have the amorphous or nanocrystalline structures, which are thermally stable. The
coatings offer specific physical properties, in particular, low friction factor and high hardness. 相似文献
3.
The reaction of O-methyl tetramethyldiamidophosphite with 3-bromopropanol or 3-bromo-2-butanol occurs with the liberation of dimethylamine and results in mixed phosphites. The reaction of O-methyl tetramethyldiamidophosphite with 3-thiocyano-2-butanol proceeds with the participation of the sulfur atom of the thiocyano group and formation ofS-(3-hydroxybutyl) tetramethyldiamidothiophosphate.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 167–169, January, 1994. 相似文献
4.
Yu. P. Kudryavtsev S. E. Evsyukov M. B. Guseva V. G. Babaev V. V. Khvostov 《Russian Chemical Bulletin》1993,42(3):399-413
The history of the discovery of carbyne, the chemical and physical methods used to obtain it, the analysis of its structure, and some of its properties are briefly considered. The prospects for its practical applications are discussedThis publication is based on a number of works on carbyne submitted for the Russian State Prize in the field of science and technology in 1993; performed at the A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences and the M. V. Lomonosov Moscow State University.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 450–463, March, 1993. 相似文献
5.
I. A. Litvinov O. N. Kataeva V. A. Naumov F. F. Guseva O. N. Nuretdinova 《Journal of Structural Chemistry》1994,34(5):823-826
A. E. Arbuzov Institute of Organic and Physical Chemistry, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 34, No. 5, pp. 185–188, September–October, 1993. 相似文献
6.
A. V. Tvardovskii A. A. Fomkin Yu. I. Tarasevich I. G. Polyakova V. V. Serpinskii I. M. Guseva 《Russian Chemical Bulletin》1992,41(1):23-28
Deformations of Na, Ca, and Ba vermiculites upon sorption of water vapor have been determined by a dilatometric method. Sequential stages in the hydration of interlayer exchange cations have been identified. The experimental results have been compared with data obtained in studies using adsorptive, calorimetric, and x-ray methods.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Institute of Colloid Chemistry and the Chemistry of Water, Academy of Sciences of the Ukraine, Kiev. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 34–39, January, 1992. 相似文献
7.
L. I. Guseva G. S. Tikhomirova 《Journal of Radioanalytical and Nuclear Chemistry》1988,121(2):345-353
The behaviour of transplutonium and rare-earth elements on anion and cation exchangers in solutions of H3PO4 and H2SO4 in the presence of oxidants (KBrO3, PbO2, (NH4)2S2O8) and in HCl solutions in the presence of reducing agents [Zn(Hg), Eu2+] depending on acid concentration as well as on oxidant content and nature in solution or in resin and other factors has been studied. Effective methods of Bk(IV), Ce(IV), Am(VI), Eu(II) and Md(II) separation from trivalent TPE and REE, as well as continuous methods of isolation of isotopically pure radionuclides250Bk,144Pr by using ion exchangers and inorganic acid solutions have been developed. 相似文献
8.
Acylation of 6-(1-fluorovinyl)-6-methyl- and 6-(2,2,3,3-tetrafluorocyclobutyl)-4,5-diazaspiro[2.4]hept-4-enes with acetyl chloride proceeds as electrophilic addition to the N(5) atom and is accompanied by opening of the cyclopropane ring to give 1-acetyl-3-(2-chloroethyl)-5-(1-fluorovinyl)-5-methyl- and 1-acetyl-3-(2-chloroethyl)-5-(2,2,3,3-tetrafluorocyclobutyl)-4,5-dihydropyrazoles, respectively. Under the same conditions, acylation of 6-(2,3,3-trifluorocyclobut-1-enyl)-4,5-diazaspiro[2.4]hept-4-ene is not regioselective. The (2-chloroethyl) pyrazolines obtained undergo dehydrochlorination into vinylpyrazolines in the presence of an excess of MeONa in MeOH. The reaction of 4-acetyl-6-(2,3,3-trifluorocyclobut-1-enyl)-4,5-diazaspiro[2.4]hept-5-ene with MeONa results in selective replacement of the F atom at the double bond by a methoxy group.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 419–422, February, 2005. 相似文献
9.
Pukhovskaya S. G. Guseva L. Zh. Semeikin A. S. Kumeev R. S. Golubchikov O. A. 《Russian Journal of Coordination Chemistry》2003,29(11):805-809
Cobalt(II) and zinc(II) complexes with 5,15-di(o-methoxyphenyl)-3,7,13,17-tetramethyl-2,8,12,18-tetra-n-buthylporphyrin and its capped analogues, where the MN4 reaction site is shielded by bridging groups containing m-phenylene and dimethoxy-substitutedp-phenylene fragments, were synthesized. Equilibrium constants of additional coordination of pyridine and N-methylimidazole by these metalloporphyrins were determined at 298 K. It was found that steric distortion of the porphyrin core destabilizes extra complexes. 相似文献
10.
Reactivity of 3,3′,5,5′-tetramethyl-4,4′dibutyldipyrrolylmethene (HL) in reactions Co(II) and Cu(II) acetates, acetylacetonates, and valinates in DMF (298.15 K) was estimated by spectrophotometric and calorimetric titration methods. The product of the exchange reaction between HL and Co acetate or acetylacetonate was found to be CoL2 complex. With an excess of Cu(II) acetate or acetylacetonate, the reaction resulted in mixed-ligand complexes CuL(AcO) and CuL(Acac), while with an excess of HL, the CuL2 complex was formed. Irrespective of the reagent concentration ratios, the exchange reactions with Cu(II) and Co(II) valinates gave ML(Val) complexes. Thermodynamic parameters of HL reactions with Cu(II) and Co(II) acetates, acetylacetonates, and valinates were determined. 相似文献