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El-Antably A. Edwards J. Williams G. Lindon P. Luke P. 《IEEE transactions on magnetics》1979,15(6):1440-1442
Theoretical and experimental results are presented for the performance of a linear reluctance motor with a ratio of airgap to pole pitch appropriate for urban transport applications. Results are given for conditions of constant current, voltage, flux or normal force; it is shown that the machine could be used for combined propulsion and magnetic suspension of a vehicle. 相似文献
96.
Au nanoparticles have distinctive absorption spectra whose peak position or particle plasmon resonance wavelength is highly sensitive to molecule adsorption on their surfaces. Spherical Au nanoparticles are surface-modified by amino-functionalized self-assembly-monolayer and used as optical probes in the fluorescence-label-free spectroscopic detection of sub-nanomole oligonucleotides. Time-resolved studies of the immobilization and hybridization of oligonucleotides on the surface of Au nanoparticles were carried out. By measuring peak shift of absorption spectra of the Au colloidal nanoparticles over time, the samples of 15 nM 20 mer target and mismatched oligonucleotides are distinguished by their different influences on the particle plasmon resonance wavelength. The approach presented in this paper extends the application of Au nanoparticles as the optical probe in oligonucleotide recognitions without prior sample labeling. 相似文献
97.
Johnson SM Wiseman RL Sekijima Y Green NS Adamski-Werner SL Kelly JW 《Accounts of chemical research》2005,38(12):911-921
Small molecule-mediated protein stabilization inside or outside of the cell is a promising strategy to treat protein misfolding/misassembly diseases. Herein we focus on the transthyretin (TTR) amyloidoses and demonstrate that preferential ligand binding to and stabilization of the native state over the dissociative transition state raises the kinetic barrier of dissociation (rate-limiting for amyloidogenesis), slowing and in many cases preventing TTR amyloid fibril formation. Since T119M-TTR subunit incorporation into tetramers otherwise composed of disease-associated subunits also imparts kinetic stability on the tetramer and ameliorates amyloidosis in humans, it is likely that small molecule-mediated native state kinetic stabilization will also alleviate TTR amyloidoses. 相似文献
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When an electron beam of a scanning electron microscope (SEM) impinges on an N-P junction, the generation of electron-hole pairs by impact ionization causes a characteristic short circuit current ISC to flow. The ISC, i.e. EBIC (electron beam induced current) depends strongly on the configuration used to investigate the cell's response. In this paper we consider the case where the plane of the junction is perpendicular to the surface. An EBIC equation amenable to numerical computations is derived as a function of cell thickness, source depth, surface recombination velocity, diffusion length, and distance of the junction to the beam-cell interaction point for a cell with an ohmic contact at its back surface. It is shown that the EBIC equation presented here is more general and easier to use than those previously reported. The effects of source depth, ohmic contact, and diffusion length on the normalized EBIC characteristic are discussed. 相似文献
100.
The catalytic mechanisms of binuclear metallohydrolases 总被引:1,自引:0,他引:1