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61.
Andrey N. Komogortsev Boris V. Lichitsky Alexander D. Tretyakov Artem N. Fakhrutdinov Arkady A. Dudinov Michail M. Krayushkin 《Journal of heterocyclic chemistry》2019,56(11):3081-3087
A convenient approach to the synthesis of the previously unknown 7H‐furo[3,2‐b]pyran‐7‐ones based on the intramolecular cyclization of carbonyl derivatives of 5‐hydroxy‐2‐methyl‐4H‐pyran‐4‐one has been elaborated. Key intermediates in the synthesis of the target 7H‐furo[3,2‐b]pyran‐7‐ones are 3‐hydroxy‐6‐methyl‐2‐(2‐oxo‐2‐arylethyl)‐4H‐pyran‐4‐ones. They are formed as a result of multicomponent condensation of 5‐hydroxy‐2‐methyl‐4H‐pyran‐4‐one with arylglyoxals and 4‐methoxyaniline. 相似文献
62.
rac-Bis[{(diphenylphosphino)ethyl}-phenylphosphino]methane (DPPEPM) reacts with iron(II) and ruthenium(II) halides to generate complexes with folded DPPEPM coordination. The paramagnetic, five-coordinate Fe(DPPEPM)Cl(2) (1) in CD(2)Cl(2) features a tridentate binding mode as established by (31)P{(1)H} NMR spectroscopy. Crystal structure analysis of the analogous bromo complex, Fe(DPPEPM)Br(2) (2) revealed a pseudo-octahedral, cis-α geometry at iron with DPPEPM coordinated in a tetradentate fashion. However, in CD(2)Cl(2) solution, the coordination of DPPEPM in 2 is similar to that of 1 in that one of the external phosphorus atoms is dissociated resulting in a mixture of three tridentate complexes. The chloro ruthenium complex cis-Ru(κ(4)-DPPEPM)Cl(2) (3) is obtained from rac-DPPEPM and either [RuCl(2)(COD)](2) [COD = 1,5-cyclooctadiene] or RuCl(2)(PPh(3))(4). The structure of 3 in both the solid state and in CD(2)Cl(2) solution features a folded κ(4)-DPPEPM. This binding mode was also observed in cis-[Fe(κ(4)-DPPEPM)(CH(3)CN)(2)](CF(3)SO(3))(2) (4). Addition of an excess of CO to a methanolic solution of 1 results in the replacement of one of the chloride ions by CO to yield cis-[Fe(κ(4)-DPPEPM)Cl(CO)](Cl) (5). The same reaction in CH(2)Cl(2) produces a mixture of 5 and [Fe(κ(3)-DPPEPM)Cl(2)(CO)] (6) in which one of the internal phosphines has been substituted by CO. Complexes 2, 3, 4, and 5 appear to be the first structurally characterized monometallic complexes of κ(4)-DPPEPM. 相似文献
63.
Il'yas S. Nizamov Elvira S. Batyeva Vladimir A. Al'fonsov Rashid Z. Musin Arkady N. Pudovik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):229-237
Abstract The reactions of tetraphosphorus trisulfide with thioacetals, aminals, sulfenamides and disulfides were studied. The reactions were found to give organothiophosphorus compounds and to be facilitated by organic amines and benzoyl peroxide. 相似文献
64.
N. V. Makarova M. N. Zemtsova I. K. Moiseev 《Chemistry of Heterocyclic Compounds》2001,37(10):1266-1269
1-Adamantyl bromomethyl ketone and 1-adamantylmethyl chloromethyl ketone react with potassium thiocyanate in dimethylformamide to give the corresponding thiocyanatoketones which cyclize under the influence of HCl into 4-(1-adamantyl) and 4(-adamantylmethyl)chlorothiazole respectively. 4-(1-Adamantyl)-2-amino-5-bromothiazole and its N-derivative were synthesized by the reaction of 1-adamantyl dibromomethyl ketone with thioureas and N-substituted thiourea in acetonitrile. 相似文献
65.
Sidorov A. A. Talismanova M. O. Fomina I. G. Aleksandrov G. G. Novotortsev V. M. Demonceau A. Nefedov S. E. Eremenko I. L. Moiseev I. I. 《Russian Chemical Bulletin》2001,50(11):2206-2211
The reaction of propargylamine with the hexanuclear complex CoII
6(3-OH)2(OOCCMe3)10(HOOCCMe3)4 or the polymer [Co(OH)n(OOCCMe3)2–n]x under an argon atmosphere afforded the unstable paramagnetic tetramine complex CoII(OOCCMe3)2(H2NCH2CCH)4 (1). In air, if an excess of propargylamine is present, the latter complex is transformed into the complex CoIII(OOCCMe3)2(NH2CH2CCH)2[2-N,N"-(HCCCH2N=CHCHCH=N—CH2CCH)] (2) containing a new ligand, viz., the 1,3-di(propargylimino)propane anion, which is a formal analog of the acetylacetonate anion. In contrast to propargylamine, 1,3-diaminopropane reacted with the CoII trimethylacetate clusters in air to produce the cationic complex [CoIII{1,3-(NH2)2(CH2)3}2(OOCCMe3)2]+OOCCMe3
– (3) without entering into condensation reactions. The structures of the resulting complexes were determined by X-ray diffraction analysis. 相似文献
66.
Gerardo Algara‐Siller Dr. Nikolai Severin Samantha Y. Chong Dr. Torbjörn Björkman Dr. Robert G. Palgrave Andrea Laybourn Prof. Dr. Markus Antonietti Prof. Yaroslav Z. Khimyak Dr. Arkady V. Krasheninnikov Prof. Dr. Jürgen P. Rabe Prof. Dr. Ute Kaiser Prof. Andrew I. Cooper Prof. Dr. Arne Thomas Dr. Michael J. Bojdys 《Angewandte Chemie (International ed. in English)》2014,53(29)
67.
68.
69.
Furoxans monosubstituted with a series of adamantanes have been obtained by oxidation of anti-[1-(3-R-adamantyl)]-amphi-glyoximes. Depending on the conditions 4-(1-adamantyl)furoxan is partially isomerized to 3-(1-adamantyl)furoxan or by increasing the time of boiling and concentration of furoxan in p-xylene is isomerized to the thermodynamically stable 3-(1-adamantyl)-1,2,4-oxadiazol-5-one.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 258–261, February, 1988. 相似文献
70.
This paper deals with the problem of optimum control for the case where the constraints are linear differential equations and the functional is of quadratic type. It is assumed that the matrix of these simultaneous equations dependsslowly on the time. The paper describes a method which permits to construct effectively asymptotic solutions of such a problem when the matrix of the characteristic equation which corresponds to Pontryagin's set of equations does not have any simple elementary divisors.Portions of this research were presented at the Colloquium on Advanced Problems and Methods for Space Flight Optimization, Liège, Belgium, 1967. 相似文献