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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.
5.
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
6.
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
7.
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
8.
Marcin Śnieżek Sebastian Stecko Irma Panfil Bartłomiej Furman Zofia Urbańczyk-Lipkowska Marek Chmielewski 《Tetrahedron: Asymmetry》2013,24(2-3):89-103
The stereoselectivity of 1,3-dipolar cycloaddition reactions of C-phenyl open-chain nitrones and α,β-unsaturated γ- and δ-lactones was investigated under thermal and catalytic conditions. It was found that under thermal conditions, the endo approach of the reactants was preferred leading to the thermodynamic product. In the presence of Sc(OTf)3 the exo adduct was obtained in high yield and selectivity. The energies of the cycloaddition reactions were investigated by means of molecular orbital calculations at the B3LYP/6-31+G(d,p) and MP3/6-31+G(d,p) theory level. Different reaction channels and reactant approaches, fitting the individual regio- and stereochemical preferences, are discussed. The computational results were compared with the corresponding experimental data and found to be in good agreement. 相似文献
9.
A simple method for the synthesis of sugar-derived imines by a Schwartz's reagent reduction of easily available sugar lactams has been described. A direct addition of nucleophiles to the generated in situ cyclic imines and subsequent deprotection of hydroxyl function allows to convert sugar lactams in polyhydroxylated pyrrolidines and piperidines. 相似文献
10.
D. B. Furman A. V. Kudryashev A. O. Ivanov L. S. Isaeva L. N. Morozova T. A. Peganova D. N. Kravtsov O. V. Bragin 《Russian Chemical Bulletin》1988,37(7):1408-1411
1. | It has been shown that in the presence of (2-methylenecyclopropane)bis(triphenyl-phosphine) nickel (Kt-1) and of a series of triphenylphosphine Ni(O) complexes the catalytic conversion of methylenecyclopropane (MCP) proceeds with the formation of identical di- and trimerization products. It is postulated that the mechanism of di- and trimerization of MCP on all Ni(O) phosphine complexes is similar, with the formation of Kt-1 as a general intermediate. |
2. | Complexes of Ni(I) and Ni(II) which have been studied were found to be inactive in MCP conversion. |