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81.
82.
83.
Alan R. Katritzky Zuoquan Wang Hengyuan Lang Peter J. Steel 《Chemistry of Heterocyclic Compounds》1996,32(6):666-671
Successive treatment of N-[(1-ethoxy)alken-2-yl]benzotriazoles VII with butyllithium and trimethylsilyl chloride in TH-Fat — 78°C followed by refluxing in acidic acetone generated ring-opened 1-(2-aminophenyl)-5-ethoxy-4-methyl-3 phenylpyrazole VIII and 4-methyl-3 phenylpyrazolo[5, 1-b]benzimidazole IX.Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 775–780, June, 1996. Original article submitted May 14, 1996. 相似文献
84.
N-Acylbenzotriazoles react with aryl isocyanates to form, depending on the type of acyl group, compounds based on five different classes of polycyclic heteroaromatics. Higher alkanoyl-, acetyl-, acetoacetyl-, aroyl-, and cinnamoylbenzotriazoles yield, respectively, derivatives of quinoline, pyrimidino[5,4-c]quinoline, benzo[b]-1,8-naphthyridine, phenanthridine, and indolo[2, 3-b]quinoline by incorporating 3, 3, 4, 2, and 2 molecules, respectively, of the isocyanate per acylbenzotriazole molecule. 相似文献
85.
A. Travers Maquenne Mathevet J. Vernay L. Bertiaux J. M. Kolthoff F. P. Treadwell Binay Chundra Mukerjee H. A. Bright C. P. Larrabee Carnegie Steel Co. Bureau of Stundards H. Beckurts L. E. Stout G. C. Whitaker J. Kassler und R. Lang 《Fresenius' Journal of Analytical Chemistry》1931,84(3-4):119-135
Ohne Zusammenfassung 相似文献
86.
D. C. Oniciu I. Ghiviriga A. R. Katritzky P. J. Steel P. Tomasik 《Chemistry of Heterocyclic Compounds》2001,37(6):723-726
The title compound is shown by X-ray crystallography and NMR spectroscopy to exist both in the solid state and in solution as such. Deuterium-induced shifts confirm the phenylamino structure for 2-phenylaminopyridine. 相似文献
87.
A critique of some recent publications (concerning the so-called inverted region in exchange-induced electronic energy transfer) is presented. It is first pointed out that the phenomena reported therein have in fact been known for nearly two decades; next, a derivation of the expression (used in the aforementioned communications) for k EnT, the transfer rate constant, is presented; finally, it is stressed that this formula cannot provide reliable quantitative predictions. 相似文献
88.
A microwave-assisted, one-pot, iridium-catalyzed aromatic C-H borylation/rhodium-catalyzed 1,4-conjugate addition sequence provides a highly robust protocol suitable for high-throughput array synthesis. Selective formation of either β-aryl-substituted ketones or the corresponding alcohols can be achieved in good overall yields by simple variation of the reaction conditions. 相似文献
89.
Antonioli B Bray DJ Clegg JK Gloe K Gloe K Kataeva O Lindoy LF McMurtrie JC Steel PJ Sumby CJ Wenzel M 《Dalton transactions (Cambridge, England : 2003)》2006,(40):4783-4794
Synthesis of the 2,2'-dipyridylamine derivatives di-2-pyridylaminomethylbenzene 1, 1,2-bis(di-2-pyridylaminomethyl)benzene 2, 1,3-bis(di-2-pyridylaminomethyl)benzene 3, 2,6-bis(di-2-pyridylaminomethyl)pyridine 4, 1,4-bis(di-2-pyridylaminomethyl)benzene 5, and 1,3,5-tris(di-2-pyridylaminomethyl)benzene 6 are reported together with the single-crystal X-ray structures of 2, 3, and 5. Reaction of individual salts of the type AgX (where X = NO(3)(-), PF(6)(-), ClO(4)(-), or BF(4)(-)) with the above ligands has led to the isolation of thirteen Ag(I) complexes, nine of which have also been characterised by X-ray diffraction. In part, the inherent flexibility of the respective ligands has resulted in the adoption of a range of coordination arrangements. A series of liquid-liquid (H(2)O/CHCl(3)) extraction experiments of Ag(I) with varying concentrations of 1-6 in the organic phase have been undertaken, with the counter ion in the aqueous phase being respectively picrate, perchlorate and nitrate. In general, extraction efficiencies for a given ionophore followed the Hofmeister order of picrate > perchlorate > nitrate; in each case the tris-dpa derivative 6 acting as the most efficient extractant of the six systems investigated. Competitive seven-metal bulk membrane transport experiments (H(2)O/CHCl(3)/H(2)O) employing the above ligands as the ionophore in the organic phase and equimolar concentrations of Co(II), Ni(II), Zn(II), Cu(II), Cd(II), Pb(II) and Ag(I) in the aqueous source phase were also undertaken, with transport occurring against a pH gradient. Under the conditions employed 1 and 5 yielded negligible transport of any of the metals present in the source phase while sole transport selectivity for Ag(I) was observed for 2-4 and 6. 相似文献
90.
J. Houben Julius Meyer F. P. Treadwell F. Heeren H. G. Martin Cl. E. Williams Arvid E. Anderson C. E. Sims B. M. Larsen E. Terres A. Pongracz H. C. M. Ingeberg F. Foerster V. Herold E. S. Peck G. Frerichs V. Coblentz O. B. May Edgar Thompson Steel Works A. D. Horlück A. Eberhard E. Schmidt Fr. Wüst N. Kirpach L. Schneider J. Parry J. J. Morgan und E. Diepschlag 《Fresenius' Journal of Analytical Chemistry》1927,71(8):297-311
Ohne Zusammenfassung 相似文献