排序方式: 共有61条查询结果,搜索用时 15 毫秒
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Wen-Ching Winnie Li 《Journal of Number Theory》2008,128(7):1941-1965
In this paper, we study the Drinfeld cusp forms for Γ1(T) and Γ(T) using Teitelbaum's interpretation as harmonic cocycles. We obtain explicit eigenvalues of Hecke operators associated to degree one prime ideals acting on the cusp forms for Γ1(T) of small weights and conclude that these Hecke operators are simultaneously diagonalizable. We also show that the Hecke operators are not diagonalizable in general for Γ1(T) of large weights, and not for Γ(T) even of small weights. The Hecke eigenvalues on cusp forms for Γ(T) with small weights are determined and the eigenspaces characterized. 相似文献
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Ming-Hsuan Kang Wen-Ching Winnie Li Chian-Jen Wang 《Israel Journal of Mathematics》2010,177(1):335-348
The zeta function attached to a finite complex X
Γ arising from the Bruhat-Tits building for PGL3(F) was studied in [KL], where a closed form expression was obtained by a combinatorial argument. This identity can be rephrased
using operators on vertices, edges, and directed chambers of X
Γ. In this paper we re-establish the zeta identity from a different aspect by analyzing the eigenvalues of these operators
using representation theory. As a byproduct, we obtain equivalent criteria for a Ramanujan complex in terms of the eigenvalues
of the operators on vertices, edges, and directed chambers, respectively. 相似文献
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Alejandro P. Bussandri Cecilia W. Kiarie Hans Van Willigen 《Research on Chemical Intermediates》2002,28(7-9):697-710
A Fourier Transform Electron Paramagnetic Resonance (FT-EPR) study was made of free radicals produced by photoinduced homolytic cleavage of the Co—C bond in methyl- and 5′-adenosylcobalamine (B12 coenzymes) and R(4-t-butyl-pyridyl)cobaloximes, R = methyl or ethyl. Spectra of methyl and adenosyl free radicals generated by the cobalamines show Chemically Induced Dynamic Electron Polarization (CIDEP) produced in precursor radical pairs. The polarization pattern can be accounted for in terms of bond cleavage via a singlet excited state of the cobalamines. In the case of methylcobalamine the polarization pattern is wavelength dependent confirming earlier findings that bond cleavage occurs via two reaction channels. Spectra of the methyl and ethyl radicals given by the cobaloximes show a remarkably strong dependence on solvent and the identity of the axial ligand trans to the leaving alkyl group. This illustrates that the character of the excited state involved in the bond cleavage reaction is strongly dependent on axial ligation of the cobalt ion. 相似文献
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FAN Caiyun JIA Hongmei Deuther-Conrad Winnie Brust Peter Steinbach Jrg LIU Boli 《中国科学B辑(英文版)》2006,49(2)
A novel 99mTc labeled complex, [N-[2-((2-oxo-2-(4-(3-phenylpropyl)piperazin-1-yl)ethyl) (2-mercaptoethyl)amino)acetyl]-2-aminoethanethiolato]Technetium(V) oxide (PPPE-MAMA′-99mTcO) ([99mTc]-2) has been designed and prepared based on the integrated approach. The corresponding rhenium complex (PPPE-MAMA′-ReO)(Re-2) has been prepared and characterized. In vitro competition binding assays show moderate affinity of Re-2 towards σ1 and σ2 receptors with Ki values of 8.67 ± 0.07 and 5.71 ± 1.88 μmol, respectively. Planar images obtained at 0.5 h, 4 h, 20 h after I.v. Injection indicate the accumulation of [99mTc]-2 in MCF-7 human breast tumor bearing mice at 20 h. Furthermore, the accumulation of [99mTc]-2 has been inhibited at 20 h after co-injection of [99mTc]-2 plus haloperidol (1 mg/kg). Biodistribution studies of [99mTc]-2 display an in vivo tumor uptake of 0.14% ± 0.01% ID/g at 24 h post I.v. Injection with a tumor/muscle ratio of 6.02 ± 0.87. The above results suggest that [99mTc]-2, derived from a previously published lead compound, retains certain tumor uptake and affinity for σ receptors. [99mTc]-2 may be used as a basis for further structural modifications to develop tumor imaging agents with high affinity for σ receptors. 相似文献
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Anbalagan V Chien W Gresham GL Groenewold GS Van Stipdonk MJ 《Rapid communications in mass spectrometry : RCM》2004,18(24):3028-3034
Electrospray ionization was used to generate mono-positive gas-phase complexes of the general formula [UO2A(S)n]+ where A = OH, Cl, Br, I or ClO4, S = H2O, CH3OH or CH3CH2OH, and n = 1-3. The multiple-stage dissociation pathways of the complexes were then studied using ion-trap mass spectrometry. For H2O-coordinated cations, the dissociation reactions observed included the elimination of H2O ligands and the loss of HA (where A = Cl, Br or I). Only for the Br and ClO4 versions did collision-induced dissociation (CID) of the hydrated species generate the bare, uranyl-anion complexes. CID of the chloride and iodide versions led instead to the production of uranyl hydroxide and hydrated UO2+. Replacement of H2O ligands by alcohol increased the tendency to eliminate HA, consistent with the higher intrinsic acidity of the alcohols compared to water and potentially stronger UO2-O interactions within the alkoxide complexes compared to the hydroxide version. 相似文献
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Bryantsev VS de Jong WA Cossel KC Diallo MS Goddard WA Groenewold GS Chien W Van Stipdonk MJ 《The journal of physical chemistry. A》2008,112(26):5777-5780
Theoretical calculations suggest a novel two-electron three-atom bonding scheme for complexation of O 2 with U(V) compounds, leading to the stabilization of superoxo complexes in the side-on (eta (2)) configuration. This binding motif is likely to play an important role in the oxidative processes involving trans-uranium compounds having valence 5f phi electrons. 相似文献
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Beekman M Kaduk JA Huang Q Wong-Ng W Yang Z Wang D Nolas GS 《Chemical communications (Cambridge, England)》2007,(8):837-839
A novel crystalline binary phase is reported in the Na-Ge system, with an entirely new, zeolite-like crystal structure solved and refined by the combination of synchrotron X-ray and neutron powder diffraction techniques. 相似文献
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