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91.
Yu. N. Belokon D. A. Chusov T. V. Skrupskaya D. A. Bor’kin L. V. Yashkina K. A. Lyssenko M. M. Il’in T. V. Strelkova G. I. Timofeeva A. S. Peregudov M. North 《Russian Chemical Bulletin》2008,57(9):1981-1988
A number of polydentate ligands based on enantiomerically pure binaphthol have been synthesized. The ligand complexes with
titanium isopropoxide were used as catalysts for the asymmetric addition of trimethylsilyl cyanide to benzaldehyde. A fragment
with axial chirality is responsible for the configuration of O-trimethylsilyl cyanohydrin product. In the case of the optimum ligand based on (R)-binaphthol and (S)-leucinol, an enantiomeric excess of 86% and quantitative yield were achieved in 4 h.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1946–1953, September, 2008. 相似文献
92.
N. V. Abramova A. G. Ginzburg A. S. Peregudov S. M. Peregudova V. I. Sokolov 《Russian Chemical Bulletin》2008,57(9):1967-1969
In new N-methyl[60]fullereno[c]pyrrolidine derivatives, the organometallic substituents in position 2 of the pyrrolidine ring are tricarbonyl(cyclopentadienyl)rhenium,
α-bicymantrenyl, and β-bicymantrenyl (also the optically active (+)-enantiomer of the latter). The electrochemical and spectroscopic
(NMR) properties of the compounds obtained were studied.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1932–1934, September, 2008. 相似文献
93.
M. L. Keshtov S. A. Kuklin I. O. Konstantinov A. S. Peregudov A. V. Muranov A. R. Khokhlov 《Doklady Chemistry》2017,472(2):25-29
A new monomer, 2,3-bis[6-fluoro-9-(2-octyldodecyl)-9H-carbazol-3-yl]-3,3'-[5,7-di(5-bromothienyl-2)thieno[3,4-b]pyrazine, M1, based on thienopyrazine containing fluorocarbazole substituents in the pyrazine ring has been synthesized. The structure of the compound has been proved by 1H and 13C NMR and elemental analysis. The HOMO and LUMO energies for monomer M1 and its precursor 3 determined by the electrochemical method are–5.03 and–3.31 eV, as well as–5.28 and–3.36 eV, respectively. Band gap widths E g ec are 1.72 and 1.92 eV for compounds M1 and 3, respectively. The new structural fragment has rather deep energy levels of frontier molecular orbitals and a small band gap width; therefore, it is a promising building block for the synthesis of polymers for organic electronics. 相似文献
94.
P. V. Zhemchugov A. S. Peregudov Yu. N. Malakhova A. I. Buzin M. I. Buzin O. I. Shchegolikhina A. M. Muzafarov 《Russian Chemical Bulletin》2015,64(6):1394-1399
First siloxane analogs of calixarenes were synthesized based on the stereoregular cis-tetraphenylcyclotetrasiloxanetetrol. Different methods were used to study properties of new compounds in bulk, as well as their behavior at the water–air interface. 相似文献
95.
I. A. Khotina A. V. Shapovalov N. S. Kushakova A. M. Sergeev A. S. Peregudov A. L. Rusanov S. A. Babich N. A. Bystrova A. I. Kovalev 《Polymer Science Series B》2011,53(11-12):578-585
The fluorenyl dendrimers 1,3,5-tris(2-fluorenyl)benzene and 1,3,5-tris[2-(9,9-dioctylfluorenyl)]benzene, which are model compounds for branched oligophenylenefluorenes, are prepared via the cyclocondensation of unsubstituted and dioctyl-substituted acetylfluorenes, respectively. Branched oligophenylenefluorenes are synthesized via the copolycondensation of phenyl-bis(pinacol diborate) with tribromoarylenes in the presence of the ferrocenyl complex of Pd via the Suzuki reaction A3 + B2. For solutions of model compounds and oligophenylenefluorenes, absorption and fluorescence spectra are measured and interpreted. In the case of the branched oligomers, no aggregation of luminophore fragments occurs, an advantageous feature that distinguishes the branched oligomers from well-known linear luminescent polymers. 相似文献
96.
Poul Erik Hansen Alexsander S. Peregudov Dimitrii N. Kravtsov Antonina I. Krylova Galina M. Babakhina Ludmila S. Golovchenko Valentina M. Pachevskaya 《Central European Journal of Chemistry》2011,9(2):253-264
Tautomerism of benzaurins and hydration are studied. 1H and 19F chemical shifts have been determined for a number of substituted 4-hydroxyphenyl-diphenyl carbinols containing fluorine
in a 3-, 3*- or 4*-position, and for similar compounds containing additional methyl groups in a position of 3, 3** or 4**.
The same data have been obtained for the fuchsones prepared by dehydration of the above carbinols. On this basis chemical
shifts of fluorine in different positions have been evaluated as a monitor of the transformation of 4-hydroxyphenyl group
to the semiquinone moiety. The 19F NMR can be used to monitor the transformation of 4**-fluorobenzaurin and the related 3,3*-disubstituted and 3,3*,5,5*-tetramethylsubstituted
compounds to the corresponding carbinols due to the addition of a water molecule and to study the tautomerism of the two latter
benzaurins as well as that of 3,3*,4**trifluorobenzaurin. Furthermore, fluorine and methyl group chemical shifts are sensitive
to syn-anti-isomerism in substituted fuchsones. 相似文献
97.
Yu. N. Belokon V. A. Larionov A. F. Mkrtchyan V. N. Khrustalev A. Nijland A. S. Saghyan I. A. Godovikov A. S. Peregudov K. K. Babievsky N. S. Ikonnikov V. I. Maleev 《Russian Chemical Bulletin》2012,61(12):2252-2260
Schiff bases derived from (1R,2R)-1,2-diaminocyclohexane and 1 eq. of salycylic (or substituted salycylic) aldehyde form stereochemically inert positively charged chiral octahedral Co iii complexes of Δ-configuration with the stereoselectivity approaching 100%. To evaluate the calatylic activity and stereoinduction of the resulting complexes with various counteranions in the outer sphere, a model reaction of trimethylsilyl cyanide addition to benzaldehyde was used. O-trimethylsilylmandelonitrile formed in the process had an enantiomeric purity up to 27%. Complexes with F? counterion showed high catalytic activity. 相似文献
98.
Yu. G. Gololobov S. V. Barabanov A. S. Peregudov P. V. Petrovskii V. N. Khrustalev 《Russian Chemical Bulletin》2012,61(6):1250-1254
The reaction of diphenylphosphorylacetonitrile with bis(dimethylamino)methane gave 2,4-bis(diphenylphosphoryl)glutaronitrile. Its rac form was obtained by the synthesis followed by crystallization. However, the reaction of the latter with bases or acids in solution yielded the meso diastereomer. 相似文献
99.
S. K. Moiseev M. A. Cherevatskaya T. A. Verbitskaya I. V. Glukhov A. S. Peregudov V. N. Kalinin 《Russian Chemical Bulletin》2012,61(10):1933-1942
The synthesis of 1-[(2-R-o-carboran-1-yl)methyl]benzotriazoles (R = Me, Ph) is described. α-Deprotonation of these compounds followed by reactions of the generated carbanions with MeI give the corresponding α-methylated products. Even at room temperature, they exist in solution as an equilibrium mixture of two conformers due to steric crowding around the Cα atom. In contrast, the anions generated by deprotonation of α-ferrocenyl derivatives of 1-methyl- and 1-ethylbenzotriazoles are ambident and are attacked by electrophiles at both the Cα and N(3) atoms. 相似文献
100.
Khakina EA Yurkova AA Peregudov AS Troyanov SI Trush VV Vovk AI Mumyatov AV Martynenko VM Balzarini J Troshin PA 《Chemical communications (Cambridge, England)》2012,48(57):7158-7160
Chlorofullerene C(60)Cl(6) undergoes highly selective reactions with thiols forming compounds C(60)[SR](5)H with high yields. These reactions open up straightforward synthetic routes to many functionalized fullerene derivatives, e.g. water-soluble compounds showing interesting biological activities. 相似文献