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Aurore Gandubert Konstantin A. Brylev Thi Thuong Nguyen Nikolai G. Naumov Noboru Kitamura Yann Molard Régis Gautier Stéphane Cordier 《无机化学与普通化学杂志》2013,639(10):1756-1762
The reaction of K4[Re6Sei8(OH)a6] · 8H2O with NaN3 in water results in the formation of [Re6Sei8(N3)a]4– units that crystallize with K+ and H2O to form K4[Re6Sei8(N3)a6] · 4H2O [P21/c (N°14), a = 9.0595(3) Å, b = 13.2457(4) Å, c = 13.2040(5) Å, β = 94.472(1)°]. In the solid state, the unit is characterized by N3 linear groups forming bond angles of roughly 120° with the Re6 cluster. The positions of the νas and νsy bands as well as N–N–N deformation modes of the N3 groups are discussed. Luminescence properties of the [Re6Sei8(N3)a]4– unit were measured in the solid state and in an acetonitrile solution. The redox potential of the [Re6Sei8(N3)a]4–/[Re6Sei8(N3)a]3– system was measured in acetonitrile. Experimental results were analyzed in the light of density functional theory calculations. 相似文献
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Four systems 1a - d were prepared to investigate the optical properties of copolymers comprised of polyfluorene doped with BODIPY-based fluors. The underlying hypothesis was energy harvested via the strong absorptivity of the major component, fluorine, would be primarily emitted from the BODIPY parts at much higher wavelengths. Optimization of the polymerization process as a function of the mol % of BODIPY, indicated that the brightest polymers were formed when approximately 4 fluorene units were co-polymerized with every BODIPY precursor. These polymers were cast into nanoparticles of ca 40 nm diameter. Treatment of clone 9 rat liver cells with suspensions of these particles resulted in uptake without encapsulation in lysosomes, or organelle targeting. 相似文献
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Solid-state NMR spectroscopy of a membrane protein in biphenyl phospholipid bicelles with the bilayer normal parallel to the magnetic field 总被引:1,自引:1,他引:0
Park SH Loudet C Marassi FM Dufourc EJ Opella SJ 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,193(1):133-138
Bicelles composed of the long-chain biphenyl phospholipid TBBPC (1-tetradecanoyl-2-(4-(4-biphenyl)butanoyl)-sn-glycero-3-PC) and the short-chain phospholipid DHPC align with their bilayer normals parallel to the direction of the magnetic field. In contrast, in typical bicelles the long-chain phospholipid is DMPC or DPPC, and the bilayers align with their normals perpendicular to the field. Samples of the membrane-bound form of the major coat protein of Pf1 bacteriophage in TBBPC bicelles are stable for several months, align magnetically over a wide range of temperatures, and yield well-resolved solid-state NMR spectra similar to those obtained from samples aligned mechanically on glass plates or in DMPC bicelle samples "flipped" with lanthanide ions so that their bilayer normals are parallel to the field. The order parameter of the TBBPC bicelle sample decreases from approximately 0.9 to 0.8 upon increasing the temperature from 20 degrees C to 60 degrees C. Since the frequency spans of the chemical shift and dipolar coupling interactions are twice as large as those obtained from proteins in DMPC bicelles without lanthanide ions, TBBPC bicelles provide an opportunity for structural studies with higher spectral resolution of the metal-binding membrane proteins without the risk of chemical or spectroscopic interference from the added lanthanide ions. In addition, the large temperature range of these samples is advantageous for the studies of membrane proteins that are unstable at elevated temperatures and for experiments requiring measurements as a function of temperature. 相似文献