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81.
3-Nitro-4-chlorocoumarin forms 3-nitro-4-substituted coumarins when it reacts with an equimolar quantity of benzyl mercaptan or thiosalicylic acid; with excess benzyl mercaptan, it forms 3,4-di-S-benzyl coumarin. 3-Nitro-4-methoxycoumarin under the same conditions, with an equimolar ratio of reagents, forms a mixture of monosubstituted and disubstituted products. A mechanism is proposed for these reactions.For Communication 1, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1476–1479, November, 1991. 相似文献
82.
Gol'dfarb Ya. L. Ostapenko É. G. Ivanov V. B. Efremkin A. F. Litvinov V. P. 《Chemistry of Heterocyclic Compounds》1982,18(11):1148-1153
A number of new dithiocarbamates of transition metals that contain thiophene, furan, benzo[b]thiophene, and benzo[b]selenophene rings were synthesized. The compounds obtained were investigated as light stabilizers for polymers. It is shown that the effectiveness of the light-stabilizing effect of the dithiocarbamate depends on the structure of the heterocyclic fragment included in its composition.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1482–1488, November, 1982. 相似文献
83.
The reaction of indoles () with superoxide ion resulted in ring cleavage to give -formyl and -acylaminoketones () or N-acylanthranilic acid () and ring expansion yielding 2-quinolones (). All reactions are chemiluminescent except that of 2-methylindole (), which gave a coupled product (). 相似文献
84.
G. I. Chipens V. A. Slavinskaya D. É. Sile É. Kh. Korchagova M. Yu. Katkevich V. D. Grigor'eva 《Chemistry of Heterocyclic Compounds》1992,28(5):576-578
Hydrogenolysis of 3-benzyloxycarbonyloxazolidine-5-one and 3-benzyloxycarbonyl-4-benzyloxazolidine-5-one by Et3SiH in the presence of F3.CCO2H is demonstrated to be a convenient method for preparing substituted N-methylaminoacids. In contrast with catalytic hydrogenation on Pd/C catalyst, the benzyloxycarbonyl is not removed and the methyl is not lost using this method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 681–683, May, 1992. 相似文献
85.
M. K. Kilevitsa Yu. A. Maurin'sh R. A. Paégle É. É. Liepin'sh A. A. Zidermane M. Yu. Lidak 《Chemistry of Heterocyclic Compounds》1981,17(11):1120-1125
1-(5-Halo-1-uracilyl)-2, 5-di-O-acetyl--D-glucofuranurono-6,3-lactones were obtained by condensation of 2,4-bis(trimethylsilyl)-5-halouracils with 1,2,5-tri-O-acetyl--D-glucofuranurono;-6, 3-lactone. The chemical transformations of these compounds were studied. The structure of the glucuronides was proved by the IR, UV, circular dichroism, and NMR spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1532–1537, November, 1981. 相似文献
86.
87.
A nonlinear correlation has been found between the 29Si-15N spin-spin coupling constants and the 15N-NMR chemical shifts in silatranes. The dependence has been used to calculate corrections to the spin-spin coupling constant for the electronegativity of a substituent on the silicon atom. This has allowed the previously obtained data on the length and order of the N Si coordinate bond for silatranes in solutions to be refined.Translated from Khimiya Geterotisiklicheskikh Soedinenii, No. 5, pp. 701–703, May, 1989. 相似文献
88.
E. L. Gaidarova K. Rosher A. É. Aliev G. V. Grishina 《Chemistry of Heterocyclic Compounds》1992,28(10):1175-1178
Enantiomericalfy pure (–)-(10S)-6,10-dimethyl-6-am-1,9-octahydroquinoline, which has been obtained from optically pure (3S)-1,3-dimethyl-3-(2-cyanoethyl)piperid-4-one, is a chiral intermediate for the preparation of novel biologically active compounds and an analog of piperidine and decahydroquinoline alkaloids. The chiroptical properties of the synthesized 6-azaoctahydroquinoline are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1379–1383, October, 1992. 相似文献
89.
P. P. Zarin' É. É. Liepin' É. S. Lavrinovich A. K. Aren 《Chemistry of Heterocyclic Compounds》1974,10(1):92-95
New 4- (benzazol-2-yl)pyridinium salts have been synthesized. Their reduction in a neutral medium with sodium tetrahydroborate has given 2-(1,2,5,6-tetrahydropyridin-4-yl)benzazoles. The catalytic hydrogenation of the latter leads to piperidine derivatives which have also been synthesized by an independent route.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 104–107, January, 1974. 相似文献
90.
A novel synthesis of polysubstituted 5-aza-indoles and polycyclic derivatives uses 2,4-dihydroxy 6-methyl pyridine, which is converted into 2-hydroxy 4-hydrazino 6-methyl pyridine from which derived hydrazones are transformed by a thermal Fischer reaction in boiling diphenylether. 相似文献