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1.
We study property (T) and the fixed-point property for actions on L
p
and other Banach spaces. We show that property (T) holds when L
2 is replaced by L
p
(and even a subspace/quotient of L
p
), and that in fact it is independent of 1≤p<∞. We show that the fixed-point property for L
p
follows from property (T) when 1<p< 2+ε. For simple Lie groups and their lattices, we prove that the fixed-point property for L
p
holds for any 1< p<∞ if and only if the rank is at least two. Finally, we obtain a superrigidity result for actions of irreducible lattices
in products of general groups on superreflexive spaces.
Bader partially supported by ISF grant 100146; Furman partially supported by NSF grants DMS-0094245 and DMS-0604611; Gelander
partially supported by NSF grant DMS-0404557 and BSF grant 2004010; Monod partially supported by FNS (CH) and NSF (US). 相似文献
2.
3.
The effect of addition of Re, Zr, Sc, and Sn on an aluminoplatinum catalyst in the reaction of dehydrogenation of propane was investigated. It was shown that addition of 0.2–0.5% Zr, Sc, or Re virtually does not alter the catalytic properties of the aluminoplatinum catalyst (APC); addition of 0.2% Sn increases the activity, selectivity, and stability of Pt/Al2O3. The amount of coke deposited on the APC after the first 5 min of work decreases by three times in the presence of Sn. The coke is more enriched with hydrogen than the other systems formed on the surface of Pt-Sn/Al2O3.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 765–771, April, 1991. 相似文献
4.
Garcia Ruano JL Alcudia A del Prado M Barros D Maestro MC Fernandez I 《The Journal of organic chemistry》2000,65(10):2856-2862
The addition of the lithium anions derived from (R)- and (S)-methyl and -ethyl p-tolyl sulfoxides to (S)-N-benzylidene-p-toluenesulfinamide provides an easy access route to enantiomerically pure beta-(N-sulfinyl)amino sulfoxides. Stereoselectivity can be achieved when the configurations at the sulfur atoms of the two reagents are opposite (matched pair), thus resulting in only one diastereoisomer, even for the case in which two new chiral centers are created. The N-sulfinyl group primarily controls the configuration of the carbon bonded to the nitrogen, whereas the configuration of the alpha-sulfinyl carbanion seems to be responsible for the level of asymmetric induction, as well as for the configuration of the new stereogenic C-SO carbon in the reactions with ethyl p-tolyl sulfoxides. An efficient method for transforming the obtained beta-(N-sulfinyl)amino sulfoxides into optically pure beta-amino alcohols, based on the stereoselective non-oxidative Pummerer reaction, is also reported. 相似文献
5.
6.
7.
D. B. Furman N. V. Volchkov L. S. Isaeva L. N. Morozova D. N. Kravtsov O. V. Bragin 《Russian Chemical Bulletin》1988,37(11):2220-2222
Conclusions By studying the liquid-phase dimerization of ethylene in the presence of Cat-Et3Al2-Cl3 catalytic systems based on a nickel complex heterogenized on Al2O3 and a number of model nickel complexes, a similar activity and selectivity of the process has been established (Cat=NiPPh3(CO)2L, where L=PPh3, CO, Al2O3; Ni(PPh3)2(CO)2; Ni(PPh3)2(2-C2H4); Ni[P(C6H11)3]2(H)Cl and Ni(PPh3)(Et)Cl).The results of the investigation agree with the hypothesis that mono- and diolefinic nickel complexes are formed as the active intermediates in the reaction.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2466–2469, November, 1988. 相似文献
8.
J. N. Spencer S. K. Berger C. R. Powell B. D. Henning G. S. Furman W. M. Loffredo E. M. Rydberg R. A. Neubert C. E. Shoop D. N. Blauch 《Journal of solution chemistry》1981,10(7):501-509
Enthalpies of solution and of transfer of amides for the solvents chloroform (CHCl3), methylenechloride (CH2Cl2), carbontetrachloride (CCl4), cyclohexane (C6H12), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), and ethylacetate (EtOAc) have been used to isolate and quantify the solvation interactions of amides in chlorinated solvents. Specific interactions at the aminde carbonyl and N–H groups have been identified. An analysis of the transfer enthalpies of pyrrole and methylpyrrole from cyclohexane to the chlorinated solvents shows that specific interactions between the pyrroles and these solvents are similar in nature. A means of calculating differences in the transfers of different solutes between the same solvent pair is given.Work done at Lebanon Valley College. 相似文献
9.
D. B. Furman L. N. Russiyan V. N. Noskova O. V. Bragin P. E. Matkovskii 《Russian Chemical Bulletin》1992,41(7):1168-1174
Reaction of Ti(O-n-Bu)4 (TBT) with AlR3 (R = Me, Et,i-Bu) in solvents such as R2O, Py, and Et3N, reduces Ti(IV) to Ti(III), Ti(II), or Ti(I). The organotitanium compounds formed by the reaction of TBT with organoaluminum compounds (OAC) undergo homolytic decomposition at the bond in Ti-C. Isotopic exchange analysis using C2D4 suggested the formation of particles containing Ti-CH2CH2-Ti, Al-CH2CH2-Al, Al-CH2CH2-Ti, M=CHCH3, and MMCHCH3 (M, M = Al or Ti) fragments. An ESR spectral analysis established that reaction of TBT with TEA in R2O, Py, and Et3N environments produced two types of paramagnetic complexes, precursors of active centers of ethylene dimerization. The influence of various factors on the kinetics of accumulation and consumption of these complexes was investigated and their structures are suggested.Deceased.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1516–1525, July, 1992. 相似文献
10.
Garcia Ruano JL Alemparte C Martin Castro AM Adams H Rodriguez Ramos JH 《The Journal of organic chemistry》2000,65(23):7938-7943
The behavior of (Z)-3-p-tolylsulfinylacrylonitrile (1) as a chiral dienophile has been evaluated from its reactions with furan and acyclic dienes. Electrostatic interactions of the cyano group with the sulfinyl one restrict the conformational mobility around the C-S bond, thus controlling the pi-facial selectivity, which is almost complete in all cases, the approach of the diene from the less-hindered face of the dienophile (that bearing the lone electron pair) in the predominant rotamer being the favored one. The regioselectivity is also completely controlled by the cyano group. Additionally, the reactivity of compound 1 as well as its endo-selectivity are both higher than those observed for the corresponding (Z)-3-sulfinylacrylates, thus proving the potential of sulfinylnitriles as chiral dienophiles. 相似文献