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71.
72.
An attempt was made to estimate the net charges of a number of cyclopentadienyl metal compounds on the basis of 19F NMR data for p-fluorophenylcyclopentadienyl metal compounds. The investigated compounds can be clearly divided into four groups according to the polarity of metal-cyclopentadienyl bond: covalent compounds (derivatives of Fe, Ru, Os, Rh and Pd) with a net charge on the η-C5H5 ring in the range from ?0.19 to ?0.29, the so-called ionic compounds (derivatives of Li, Na and K) with a net charge on the ring ?0.64 ÷ ?0.72, and compounds with an intermediate character of the bond (derivatives of Cu, Mg and T1) with a net charge of ?0.44 ÷ ?0.46; the net charge on the rings of cyclopentadienyl manganese tricarbonyl and -rhenium tricarbonyl is near to zero. When the effective charge on the ring is near ?0.44 the cyclopentadienyl metal compounds are able to dissociate into ions in solution. 相似文献
73.
The transition process from steady convection to chaos is experimentally studied in thermocapillary convections of floating half zone. The onset of temperature oscillations in the liquid bridge of floating half zone and further transitions of the temporal convective behaviour are detected by measuring the temperature in the liquid bridge. The fast Fourier transform reveals the frequency and amplitude characteristics of the flow transition. The experimental results indicate the existence of a sequence of period-doubling bifurcations that culminate in chaos. The measured Feigenbaum numbers are δ2 =4.69 and δ4 = 4.6, which are comparable with the theoretical asymptotic value δ=4.669. 相似文献
74.
Conclusions Employing the -resonance spectroscopy method, it was shown that in biferrocenyl in the solid phase the exchange of an electron proceeds at a rate that is less than 107 sec–1.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimi-cheskaya, No. 1, pp. 132–134, January, 1973. 相似文献
75.
76.
Conclusions The19F NMR chemical shifts of the ferrocenyl(p-fluorophenyl) and ruthenocenyl(p-fluorophenyl) carbocations testify to the greater effectiveness of the ruthenocenyl group over the ferrocenyl group in delocalizing the positive charge.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 711–712, March, 1984.The authors are grateful to M. V. Galakhov for assistance in obtaining the1H and19F NMR spectra. 相似文献
77.
V. I. Zdanovich V. Yu. Lagunova F. M. Dolgushin A. I. Yanovsky M. G. Ezernitskaya P. V. Petrovskii A. A. Koridze 《Russian Chemical Bulletin》1998,47(9):1789-1796
Ruthenium carbonyl triphenylphosphine complexes Ru2(CO)6−n
(PPh3)
n
{μ-C(CH=CHPh)C(Ph)C(CH=CHPh)C(Ph)} (n=1, 2) were obtained by the reaction of complex Ru2(CO)6{μ-C(CH=CHPh)C(Ph)C(CH=CHPh)C(Ph)} containing the ruthenacyclopentadiene moiety with PPh3 in refluxing toluene. The complexes were characterized by IR and by1H,13C, and31P NMR spectroscopy, and by X-ray analysis. The monophosphine derivative is identical to the complex formed by fragmentation
of the Ru3(CO)8(PPh3){μ-C(CH=CHPh)C(Ph)C(CH=CHPh)C(Ph)} cluster and contains the PPh3 ligand at the ruthenium atom of the ruthenacyclopentadiene moiety.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1836–1843, September, 1998 相似文献
78.
A.A. Koridze O.A. Kizas P.V. Petrovskii N.E. Kolobova Yu.T. Struchkov A.I. Yanovsky 《Journal of organometallic chemistry》1980,338(1):81-87
Clusters Os3H(Cl)(CO)9(L) (L= CO, PMe2Ph) react with lithium phenyl-acetylide to yield Os3H(CO)9(L)(μ-η2-CCPh),which has a bridging acetylide ligand. The Os3H(CO)10(μ-η2-CCPh) complex (II) is fluxional owing to rapid π → σ, σ → π interchange of acetylide ligand between the bridged osmium atoms, whereas the phosphine-substituted derivative, Os3H(CO)9(PM2Ph)(μ-η2-CCPh) (III), is stereochemically rigid and exists at room temperature in two isomeric forms. These isomers have been isolated as solids and have been characterized by 1H and 31P{1H} NMR spectroscopy. According to the spectroscopic data, in the major (IIIa) and minor (IIIb) isomers the phosphine ligand is coordinated to the metal atom which is σ- or π-bonded to the bridging acetylide group, respectively. The isomerization of IIIb into IIIa occurs only at 80°C. The structure of IIIa has been confirmed by an X-ray diffraction study. 相似文献
79.
S. V. Safronov A. M. Sheloumov A. Z. Kreindlin A. A. Kamyshova F. M. Dolgushin A. F. Smolyakov P. V. Petrovskii M. G. Ezernitskaya A. A. Koridze 《Russian Chemical Bulletin》2010,59(9):1740-1744
The first ruthenocene- and pentamethylruthenocene-based ruthenium pincer complexes, RuCl(CO)[{2,5-(But
2PCH2)2C5H2}Ru(C5H5)] and RuCl(CO)[{2,5-(But
2PCH2)2C5H2}Ru-(C5Me5)], were synthesized by cyclometallation of {1,3-(But
2PCH2)2C5H2}Ru(C5H5) and {1,3-(But
2PCH2)2C5H2}Ru(C5Me5), respectively, with RuCl2(DMSO)4 in 2-methoxyethanol and characterized by 1H and 31P{1H} NMR spectroscopy, and X-ray diffraction. 相似文献
80.
A. A. Kamyshova A. Z. Kreindlin P. V. Petrovskii A. S. Peregudov Yu. A. Borisov A. A. Koridze 《Russian Chemical Bulletin》2005,54(12):2805-2812
The reaction of [Cp*2RuBr]+Br− with bromine in CH2Cl2 (CD2Cl2) in an inert atmosphere at room temperature produces the complexes [Cp*Ru(Br)C5Me4CH2Br]+Br3
− (syn conformer), [Cp*Ru(Br)C5Me3(CH2Br)2]+ (syn and anti conformers), and [Ru(Br)(C5Me4CH2Br)2]+ (syn conformer). All complexes were characterized by 1H and 13C NMR spectroscopy; the former complex, by elemental analysis. These complexes were also prepared by the reaction of [Cp*RuC5Me4CH2]+BF4
− with bromine in CH2Cl2.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2712–2718, December, 2005. 相似文献