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The far-infrared and infrared reflection spectra of Tl2Ba2Ca2Cu3O10 superconducting film are reported in this paper. It is found there are three sharp reflection edges in both the superconducting and normal states, their positions being near ≈ 150, ≈ 350 and ≈600 cm-1. We attribute these reflection spectra to the Drude free carriers and a wide mid-infrared absorption band. When the incident angle increases from 7° to 30°, some additional stractures appear in the refiection spectra, which are the A2u phonon modes vibrating along c-axis. 相似文献
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CHEN Zhi-hong XU Li BA Xue-qing ZENG Xian-lu 《高等学校化学研究》2006,22(3):302-307
Introduction Migrationandrecruitmentofleukocytesfromblood toinflammatorylesionsitesaresequentiallyregulated byadhesionmoleculesandtheirreceptors[1].These lectinfamilyplaysamajorroleininitiatingattachement ofneutrophilstotheactivatedendothelium.P selectin,… 相似文献
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高压电场作用下乙醇-水溶液体系变化红外光谱分析 总被引:1,自引:0,他引:1
本文报道了用红外光谱分析电磁场作用下乙醇 水溶液体系变化情况。分析结果表明 :当乙醇溶液受到 2 0kV·cm- 1 的交变电磁场处理 (5 0Hz)时 ,分子之间的氢键缔合先增大后减少 ;高乙醇含量溶液受到同样强度电场较长时间处理时 ,有乙醇发生氧化反应 ,从红外谱中可看到νCO 峰及ν(OH) (H2 O) 峰的出现 ;经处理后的溶液自然放置 7天再测定 ,其红外谱图基本保持不变。文中对各出现变化的峰进行了分析 ,并对其机理进行了推导 相似文献
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We present integral-type Darboux transformation for the mKdV hierarchy and for the mKdV hierarchy withself-consistent sources. In contrast with the normal Darboux transformation, the integral-type Darboux transformationscan offer non-auto-Backlund transformation between two (2n 1)-th mKdV equations with self-consistent sources withdifferent degrees. This kind of Darboux transformation enables us to construct the N-soliton solution for the mKdVhierarchy with self-consistent sources. We also propose the formulas for the m times repeated integral-type Darbouxtransformations for both mKdV hierarchy and mKdV hierarchy with self-consistent sources. 相似文献
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By numerical simulations on frequency dependence of the spiking threshold, i.e. on the critical amplitude of periodic stimulus, for a neuron to fire, we find that bushy cells in the cochlear nuclear exhibit frequency selec- tivity behaviour. However, the selective frequency band of a bushy cell is far away from that of the preferred spectral range in human and mammal auditory perception. The mechanism underlying this neural activity is also discussed. Further studies show that the ion channel densities have little impact on the selective frequency band of bushy cells. These findings suggest that the neuronal behaviour of frequency selectivity in bushy cells at both the single cell and population levels may be not functionally relevant to frequency discrimination. Our results may reveal a neural hint to the reconsideration on the busily cell functional role in auditory information processing of sound frequency. 相似文献
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We propose a method to realize the teleportation of an unknown entangled state that consists of many qudits through a partially entangled-qudit quantum channel with the help of 2 log2 d-bit classical communication. The operations used in the teleportation process include a generalized Bell-state measurement and a series of singlequdit π-measurements performed by Alice, a series of generalized qudit-Pauli gates and two-level unitary gates, as well as a qubit measurement performed by Bob. For a maximally entangled quantum channel, the successful probability of the teleportation becomes unit. 相似文献