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1.
2.
The aim of this work is to provide a combinatorial resolution of the local components of some automorphic forms of a general
linear group in a suitable way to realize them as transfer of packets of local components of square integrable automorphic
forms for classical groups. We obtain explicit transfer for Arthur’s packets. 相似文献
3.
Densities of water+acetonitrile mixture have been measured from 308.15 to 278.15 K over the entire composition range. Partial molal volumes of both components of the mixed system have been calculated and deviations from ideal volumes of mixing have been evaluated. Literature data on viscosity have also been treated by a least square method and activation thermodynamic functions of viscous flow computed. Structural correlations have been made with previous results on acid-base properties; they allow to distinguish several interaction regions between components of binary systems. 相似文献
4.
Colette Deschamps-Vallet Jean-Baptiste Ilots Michle Meyer-Dayan Darius Molho 《Journal of heterocyclic chemistry》1982,19(1):97-101
3-Phenyl-1-benzopyrylium percholorates 1a, 1i react exculusively at C-2 with ethanol and isopropyl alcohol, affording mixed acetals 2a, 3a, 3i . Aqueous ammonia gives symmetrical secondary amines 4a, 4b or bis(3-phenyl-2H-1-benzopyran-2-yl)amines, while with aqueous aliphatic amines (40%) bis-acetals 5a, 5b or 2,2′-oxy-bis(3-phenyl-2H-1-benzopyrans) are characterized. In some other acidic conditions, 5a and 5b are also obtained. 相似文献
5.
Paul Servin Régis Laurent Anne-Marie Caminade Jean-Pierre Majoral 《Tetrahedron letters》2007,48(4):579-583
A series of densely functionalized dendrimers is synthesized using two branched monomers of type AB2 and CD2, in which the A function (NH2) reacts with D (CHO) and the B function (Cl) reacts with C (OH). The reaction has been carried out up to the fourth generation possessing 96 end groups and has been obtained in only four steps. 相似文献
6.
Marchand P Griffe L Caminade AM Majoral JP Destarac M Leising F 《Organic letters》2004,6(8):1309-1312
The functionalization of phosphorus-containing dendrimers was easily achieved through thioacylation reactions involving new dendrimers capped with dithioester end groups and various functionalized amines. These reactions were successfully applied to the first generation (12 end groups) and the third generation of the dendrimer (48 end groups) and allowed their functionalization by various primary or secondary amines, alcohols, glycols, and azides. [reaction: see text] 相似文献
7.
Photosystem I (PSI) is one of two photosynthetic reaction centers present in plants, algae, and cyanobacteria and catalyzes the reduction of ferredoxin and the oxidation of cytochrome c or plastocyanin. The PSI primary chlorophyll donor, which is oxidized in the primary electron-transfer events, is a heterodimer of chl a and a' called P700. It has been suggested that protein relaxation accompanies light-induced electron transfer in this reaction center (Dashdorj, N.; Xu, W.; Martinsson, P.; Chitnis, P. R.; Savikhin, S. Biophys. J. 2004, 86, 3121. Kim, S.; Sacksteder, C. A.; Bixby, K. A.; Barry, B. A. Biochemistry 2001, 40, 15384). To investigate the details of electron transfer and relaxation events in PSI, we have employed several experimental approaches. First, we report a pH-dependent viscosity effect on P700+ reduction; this result suggests a role for proton transfer in the PSI electron-transfer reactions. Second, we find that changes in hydration alter the rate of P700+ reduction and the interactions of P700 with the protein environment. This result suggests a role for bound water in electron transfer to P700+. Third, we present evidence that deuteration of the tyrosine aromatic side chain perturbs the vibrational spectrum, associated with P700+ reduction. We attribute this result to a linkage between CH-pi interactions and electron transfer to P700+. 相似文献
8.
Claude G. Andrieu Colette Chatain-Cathaud Marie Claude Fournié-Zaluski 《Journal of Molecular Structure》1974,22(3):433-444
The carbonyl bands of 2-formyl and 3-formyl-furans [18O] are determined and explained. The magnitude of the inductive and mesomeric effects in 2-acyl and 3-acyl-thiophenes and furans is discussed on the basis of a comparison of the frequencies and the intensities of the v(CO) and v(CC) bands. The conformational preference of some aroyl-furans and aroyl-formyl-furans and the rotation around the C(Ar)-C(O) bonds are related to these parameters. 相似文献
9.
Arindam Mukherjee Robert W. Gable Colette Boskovic 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(2):m71-m73
The molecule of the title compound, tetra‐μ2‐acetato‐diaquadi‐μ2‐chloro‐tetrachlorotetrakis[μ4‐3‐hydroxy‐2,2‐bis(oxidomethyl)propanolato]tetramethanoldi‐μ3‐methanolato‐di‐μ5‐oxo‐octamanganese(II)tetramanganese(III), [Mn4IIIMn8II(CH3O)2(C2H3O2)4(C5H9O4)4Cl6O2(CH4O)4(H2O)2], displays a centre of symmetry. The structure of the {Mn4IIIMn8IIO18Cl2}10− core is composed of three layers and features two oxo ligands binding in a rare μ5‐mode. 相似文献
10.