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41.
Reinvestigation of the acid-catalyzed cyclization of 1-(3-hydroxypropynyl)cyclododecan-1-ol under the conditions of the Nazarov
reaction demonstrated that this conversion yields two isomeric bicyclic ketones, namely, bicyclo[10.3.0]pentadec-1(12)-en-13-one
and bicyclo[10.3.0]pentadec-1-en-3-one. The latter compound is thermodynamically less stable.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1325–1327, July, 1997. 相似文献
42.
A.A. Koridze P.V. Petrovskii A.I. Mokhov A.I. Lutsenko 《Journal of organometallic chemistry》1977,136(1):57-63
The chemical shifts of C(2,5) and C(3,4) carbons in the 13C NMR spectra of monosubstituted ferrocenes have been assigned using deuterium labelling. An analogy is observed between the shielding of C(2,5) and C(3,4) carbons of ferrocene derivatives and ortho- and para-carbons of benzene derivatives withthe same substituents. Electron-density distribution in the cyclopentadienyl ring is discussed on the basis of 13C NMR data. 相似文献
43.
L. N. Novikova N. A. Ustynyuk B. L. Tumanskii P. V. Petrovskii A. A. Borisenko S. V. Kukharenko V. V. Strelets 《Russian Chemical Bulletin》1995,44(7):1306-1310
The oxidation of the carbon-centered [(6-C13H9)Cr(CO)3]– anion (1
–) results in formation of (-6:6-9,9-bifluorenyl)bis-chromiumtricarbonyl (3) due to coupling of the intermediate carbon-centered radical (1.). The oxidation of the metal-centered anion [(5-C13H9)Cr(CO)3]– (2
–), which is isomeric to the 1– anion, gives an equilibrium mixture of the chromium-centered radical {(5-C13H9)Cr(CO)3}. (2
.) and its dimer [(5-C13H9)Cr(CO)3]2 (6). Radical2
. readily reacts with MeI and the solvent (THF); the resulting derivatives, (5-C13H9)Cr(CO)3R (R=Me (10); R=H (7)), undergo fast ricochet inter-ring 56 rearrangements into (6-9R-C13H9)Cr(CO)3 (R=CH3 (9); R=H (4)).Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1354–1358, July, 1995.The authors are grateful to D. V. Zagorevskii who recorded the mass spectra. This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-05209) and the International Science Foundation (Grant Nos. MQ 4000 and REV 000). 相似文献
44.
Gololobov Yu. G. Galkin V. I. Petrovskii P. V. Linchenko O. A. Zueva E. M. Mubarakova L. G. Cherkasov R. A. Schmutzler R. Ernst L. Jones P. G. Freytag M. 《Russian Chemical Bulletin》2003,52(9):1920-1927
Studies by 1H NMR spectroscopy and X-ray diffraction analysis revealed hindered rotation of the aromatic substituent about the CAr—N bond in ortho-substituted (except for o-fluorine-substituted) phosphorus-containing carbamates. The energy barriers to rotation (G
c
) and coalescence temperatures (T
c) determined by the coalescence method increase with increasing volume of the ortho substituent. Conformations resulting from rotation of the ortho-substituted aryl group about the CAr—N bond were analyzed by quantum-chemical methods, potential curves were constructed, and differences between the conformational energies and the heights of rotation barriers were estimated. The theoretical rotation barriers change in parallel with the experimental values of G
c
; however, the theoretical values are much smaller in magnitude. 相似文献
45.
Tikhonova I. A. Shubina E. S. Dolgushin F. M. Tugashov K. I. Teplitskaya L. N. Filin A. M. Sivaev I. B. Petrovskii P. V. Furin G. G. Bregadze V. I. Epstein L. M. Shur V. B. 《Russian Chemical Bulletin》2003,52(3):594-600
The reaction of cyclic trimeric perfluoro-o-phenylenemercury (o-C6F4Hg)3 (1) with the polyhedral [B12H11SCN]2– anion in THF at 20 °C affords the {[(o-C6F4Hg)3](B12H11SCN)}2– (4) and {[(o-C6F4Hg)3]2(B12H11SCN)}2– (5) complexes. Complex 5 was isolated as the tetrabutylammonium salt. X-ray diffraction analysis showed that this complex has a bent-sandwich structure in which the [B12H11SCN]2– anion is located between the planes of two molecules 1 and is coordinated to both these molecules through B—H—Hg bridges and S—Hg bonds. The stability constants of complexes 4 and 5 in THF (20 °C), which were determined from the IR spectroscopic data, are 16 L mol–1 and 992 L2 mol–2, respectively. 相似文献
46.
A. R. Kudinov D. A. Loginov P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1998,47(8):1583-1584
Thirty-electron triple-decker complexes with a central pentaphospholyl ligand [(η-C5Me5)Fe(μ-η:η-P5)M(η-C5R5)]BF4 (M=Fe, R=Me or M=Ru, R=H, Me) were synthesized by a stacking reaction of cationic 12-electron fragments [(η-C5R5)M]+ with (η-C5Me5)Fe(η-P5).
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1625–1626, August, 1998. 相似文献
47.
V. N. Lebedev E. V. Balagurova S. M. Peregudova L. I. Denisovich M. G. Peterleitner L. E. Knogradova P. V. Petrovskii L. I. Zakharkin 《Russian Chemical Bulletin》1996,45(12):2835-2839
B-Flourosubstituted cyclopentadienyldicarbollylcobalt and -iron were synthesized. Electrochemical studies of iron 5-C5H5-3,1,2-FeC2B9H11–n
F
n
(n = 2–4) complexes were carried out.19F NMR, UV, and IR spectra of the cobalt and iron complexes were obtained.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2984–2989, December, 1996, 相似文献
48.
Conclusions The reaction of perfluoroketones with alkylvinyl ethers leads to 2-alkoxy-4,4-bis(perfluoroalkyl) oxethanes, subsequent isomerization of which yielded-alkoxyvinyl-bis(perfluoroalkyl)carbinols.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 918–921, April, 1967. 相似文献
49.
Koridze A. A. Kuklin S. A. Petrovskii P. V. Dolgushin F. M. Ezernitskaya M. G. 《Russian Chemical Bulletin》2002,51(2):350-353
The Os3(-H)2(CO)7(-C6H4){3-Ph2PCH2P(C6H4)Ph} complex, which was isolated from the products of thermolysis of Os3(CO)10(-dppm) (dppm is Ph2PCH2PPh2) in toluene, was characterized by X-ray diffraction analysis. Protonation of the resulting complex with trifluoroacetic acid afforded the cationic complex [Os3(-H)3(CO)7(-C6H4){3-Ph2PCH2P(C6H4)Ph}]+. 相似文献
50.
A. R. Kudinov L. S. Shul'pina P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1992,41(3):549-554
Interaction of [Ru(-C
6
H
6
)Cl
2
]
2
with indenyl- or fluorenyllithium in THF gives, together with cationic benzene complexes [Ru(
5
-C
9
H
7
)(-C
6
H
6
)]+ and [Ru(
5
-C
13
H
9
)(-C
6
H
6
)]+, the neutral cyclohexadienyl derivatives Ru(
5
-C
9
H
6
-C
9
H
7
) and Ru(
5
-C
13
H
9
)(
5
-C
6
H
6
-C
13
H
9
), respectively. Interaction of the cyclohexadienyl complexes with Al
2
O
3
, Ph
3
C+, and CF
3
CO
2
H has been studied. Reaction of Ru(
5
-C
13
H
9
)(
5
-C
6
H
7
) with CF
3
CO
2
H in the presence of an arene yields cationic cyclohexadienylarene complexes: [Ru(
5
-C
13
H
9
)(
6
-arene)]+ (arene=C
6
H
6
or 1,3,5-Me
3
C
6
H
3
).A. N. Nesmeyanov Institute of Organoelemental Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 699–706, March, 1992. 相似文献