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1.
A. I. Grachev 《Physics of the Solid State》2004,46(3):442-444
The phenomenology of the photogalvanic effect permits prediction of a number of physical phenomena, the most interesting of which is the galvano-dipolar effect. This effect consists in the appearance of an electric dipole moment in a sample through which an electric current is passed. A possible microscopic mechanism of this phenomenon, which can be realized in centrosymmetric media as well, is considered. 相似文献
2.
V. L. Bychkov L. P. Grachev I. I. Esakov A. A. Ravaev K. V. Khodataev 《Technical Physics》2004,49(7):833-838
A longitudinal dc electric discharge in a submerged high-pressure supersonic air jet is described. Photographs of the discharge
are provided. The experimental voltage across the discharge gap and the discharge current are given for two resistances of
the resistor that limits the discharge current over a certain range of the discharge channel length along the air flow. The
current-voltage discharge characteristic is provided at a constant discharge length. The main discharge characteristics are
obtained from a comparison of the experimental and theoretical results calculated on the basis of the simplest model. 相似文献
3.
Synthesis of Phosphocapped Derivatives of β-Cyclodextrin 总被引:1,自引:0,他引:1
Kurochkina G. I. Grachev M. K. Sutyagin A. A. Nifant'ev E. E. 《Russian Journal of General Chemistry》2003,73(12):1945-1946
Russian Journal of General Chemistry - 相似文献
4.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 3, pp. 418–432, March, 1991. 相似文献
5.
The kinetics of the free-radical polymerization of styrene at 120°C in the presence of alkoxyamine as a living polymerization agent has been studied. The alkoxyamine forms in situ with a 100-fold variation in the initial concentration of 2,2,6,6-tetramethyl-1-piperidinyloxy. The rate of the process at the stationary stage decreases with an increase in the initial concentration of 2,2,6,6-tetramethyl-1-piperidinyloxy. The computer simulation of the kinetic features of the process under study demonstrates that this tendency is related to the possible secondary inhibition of the process by alkoxyamine and/or hydroxylamine arising in the system in the course of polymerization. 相似文献
6.
Hsueh SY Muller D Tang J Winston R Zapalac G Swallow EC Berge JP Brenner AE Grafstrom P Jastrzembski E Lach J Marriner J Raja R Smith VJ McCliment E Newsom C Anderson EW Denisov AS Grachev VT Kulikov AV Schegelsky VA Seliverstov DM Smirnov NN Terentyev NK Tkatch II Vorobyov AA Cooper PS Razis P Teig LJ 《Physical review letters》1985,54(22):2399-2402
7.
Backinowsky LV Abronina PI Shashkov AS Grachev AA Kochetkov NK Nepogodiev SA Stoddart JF 《Chemistry (Weinheim an der Bergstrasse, Germany)》2002,8(19):4412-4423
Glycosylation of sugar trityl ethers with sugar 1,2-O-(1-cyano)ethylidene derivatives (the trityl-cyanoethylidene condensation) has been applied to the synthesis of highly branched (dendritic) mannooligosaccharides incorporating a Manalpha1-->3(Manalpha1-->6)Man structural motif. The convergent synthetic strategy used to assemble these oligosaccharides was based on the use of glycosyl acceptors and/or a glycosyl donor already bearing this structural motif. The former were represented by mono- and ditrityl ethers of ManalphaOMe, Manalpha1-->3ManalphaOMe, and Manalpha1-->3(Manalpha1-->6)ManalphaX, where X=OMe or SEt. The pivotal glycosyl donor was the peracetylated 1,2-O-(1-cyano)ethylidene-3,6-di-O-(alpha-D-mannopyranosyl)-beta-D-mannopyranose (1), prepared by orthogonal Helferich glycosylation of the known 1,2-O-(1-cyano)ethylidene-beta-D-mannopyranose with tetra-O-acetyl-alpha-D-mannopyranosyl bromide followed by O-acetylation. Glycosylation of acetates of methyl 6-O-trityl-alpha-D-mannopyranoside and methyl 3,6-di-O-trityl-alpha-D-mannopyranoside with one equivalent of the donor 1 gave rise to the isomeric tetrasaccharide derivatives, Manalpha1-->3(Manalpha1-->6)Manalpha1-->6ManalphaOMe and Manalpha1-->3(Manalpha1-->6)Manalpha1-->3ManalphaOMe, respectively. The latter derivative was further mannosylated at the remaining 6-O-trityl acceptor site to give the protected pentasaccharide Manalpha1-->3(Manalpha1-->6)Manalpha1-->3(Manalpha1-->6)ManalphaOMe. The isomeric pentasaccharide, Manalpha1-->3(Manalpha1-->6)Manalpha1-->6(Manalpha1-->3)ManalphaOMe, was prepared by reaction of 1 with the 6-O-trityl derivative of (Manalpha1-->3)ManalphaOMe. In a similar fashion, 6'- and 6"-O-trityl derivatives of the branched trisaccharide Manalpha1-->3(Manalpha1-->6)ManalphaOMe served as precursors for two isomeric mannohexaosides. The 3,6-di-O-trityl ether of ManalphaOMe and the 6',6"-di-O-trityl ether of Manalpha1-->3(Manalpha1-->6)ManalphaX (X=OMe or SEt) were efficiently bis-glycosylated with the donor 1 to give the corresponding protected mannoheptaoside and mannononaoside. The yields of these glycosylations with the donor 1 ranged from 50 to 66 %. Final deprotection of all the oligosaccharides was straightforward and afforded the target products in high yields. Both the acylated and deprotected products were characterized, and the intersaccharide connectivities were elucidated by extensive one- and two-dimensional NMR spectroscopy. The described blockwise convergent approach allows assembly of a variety of 3,6-branched mannooligosaccharides. 相似文献
8.
A. I. Pavlyuchenko V. V. Titov N. I. Smirnova V. T. Grachev 《Chemistry of Heterocyclic Compounds》1980,16(7):681-684
Liquid-crystal 2-cyano-5-[p-alkyl(alkoxy)phenyl]pyridines were synthesized by the reaction of 1-dimethylamino-3-dimethylimmonia-2-[p-alkyl (alkoxy)phenyl]propene perchlorates with 2-acetylfuran and subsequently through 2-furyl-5-[p-alkyl(alkoxy)phenyl]pyrylium perchlorates and 2- (2-furyl)-5-[p-alkyl (alkoxy)phenyl]pyridines by conversion of the latter to 5-alkyl(alkoxy)phenylpyridine-2-carboxylic acids, from which the cyano derivatives were obtained by the usual scheme through the amides. The intermediate arylfurylpyridines and arylpyridine-2-carboxylic acid imides also display liquid-crystal properties.Translated from Khimiya Geterotskilicheskikh Soedinenii, No. 7, pp. 888–891, July, 1980. 相似文献
9.
V. T. Grachev A. V. Ivashchenko S. P. Ivashchenko B. G. Gerasimov V. N. Lisyutenko B. E. Zaitsev 《Chemistry of Heterocyclic Compounds》1982,18(9):974-978
The tautomerism, electronic spectra, and electronic structures of the ground and excited states of indolo [2,3-b]quinoxaline and its 2,3- and 1,4-dibutoxy derivatives were investigated by the Pariser-Parr-Pople (PPP) method. It is shown that these compounds exist primarily in the 6H form; the long-wave s* transition is due to transfer of charge from the indole fragment to the quinoxaline fragment, and in the first excited state many of the bonds in the quinoxaline fragment are loosened significantly. The effect of butoxy substituents on the first s* transition of indolo [2,3-b] quinoxaline was analyzed by means of perturbation theory within the framework of the Hückel MO method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1259–1263, September, 1982. 相似文献
10.
P. A. Storozhenko A. A. Grachev A. O. Klochkov V. I. Shiryaev 《Russian Journal of Applied Chemistry》2013,86(3):387-393
Continuous organomagnesium synthesis of a number of organic derivatives of 14th group elements of the periodic table was examined in a column apparatus with an agitator. An effect of a molar ratio of reactants, temperature in a reaction zone, and other factors was studied on the yield and composition of the products. 相似文献