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排序方式: 共有192条查询结果,搜索用时 31 毫秒
181.
In recent study adaptive decomposition of functions into basic functions of analytic instantaneous frequencies has been sought. Fourier series is a particular case of such decomposition. Adaptivity addresses certain optimal property of the decomposition. The present paper presents a fast decomposition of functions in the $\mathcal {L}^{2}(\partial {\mathbb{D}})$ spaces into a series of inner and weighted inner functions of increasing frequencies. 相似文献
182.
Through first-principles calculations and thermodynamic analysis, we investigate the stable chemical potential range for BiAlO3 with R3c and Pm3m symmetry. The possible vacancies of BiAlO3 are mostly at their charged state rather than neutral state. And vacancies are more easily formed in R3c system than Pm3m system under same condition. 相似文献
183.
184.
以企业为价值感受主体、客户为价值感受客体的客户价值,衡量了客户对企业的相对重要性.首先基于传导变换理论,给出传导知识的定义,然后建立传导度以度量主动变换导致客户价值发生传导变换的效果,探讨了客户价值传导信息元集和传导知识的获取.研究可以为企业提供制定客户关系管理策略的依据,为客户价值研究提供新的思路. 相似文献
185.
We present a first-principles calculation for the structural, magnetic, and electronic properties of LiMBO3 (M = Mn, Fe, Co). Along the [0 0 1] direction, transition metals shows antiferromagnetic coupling in LiMBO3 of both hexagonal and monoclinic lattices. The calculated magnetic moment of 5μB per formula unit is close to the experimental value. These compounds are semiconductors with band gap of 0.4-2 eV, and with average intercalation voltages of 2-4.8 V. 相似文献
186.
蛋白质与酸性染料相互作用的分光光度研究 总被引:6,自引:0,他引:6
分别在酸性和碱性介质研究了铬天青S(CAS),溴甲酚绿(BCG),溴邻苯三酚红(BPR)和甲基百里酚蓝(MTB)与蛋白质结合的光度性质.在pH3.8~4.0,蛋白质使CAS和BCG的吸光度降低,在pH3.8和10.8,蛋白质分别使BPR和MTB最大吸收波长红移10和20nm,并使染料吸光度增大.无论染料吸光度降低或增大,均与蛋白质浓度在一定浓度范围内成正比.初步讨论了蛋白质与染料作用的机理. 相似文献
187.
铂电极上醋酸-醋酐溶液中Mn(III)/Mn(II)电对研究 总被引:2,自引:0,他引:2
平衡电极电势实验确定了25 ℃, 1.5 mol•L-1醋酸钾+醋酸-醋酐(3:1体积比)溶液中Mn(III)/Mn(II)的条件电极电势为0.719 V(vs SCE);采用电势扫描和旋转圆盘电极技术研究了醋酸-醋酐溶液中铂电极上Mn(III)/Mn(II)电对的阳极氧化动力学. 结果表明:Mn(II)阳极氧化成Mn(III)的电极反应控制步骤属电荷传递过程, 阳极传递系数β=0.347,交换电流密度i0=5.84×10-6 A•cm-2,阳极标准反应速率常数ka=1.35×10-8 m•s-1, Mn(II)和OAc-的反应级数均为一级. 相似文献
188.
189.
Xiangbo Yang Youyan Liu 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,15(4):625-631
After establishing the method of constructing a class of one-dimensional (1D) Fibonacci-class quasiperiodic (FC(n)) ferroelectric domains system, we have studied the properties of the electric field of the second harmonic generation (SHG)
by means of the small-signal approximation in the case of the vertically transmission. It was found that only the second harmonic
light (SHL) peaks which were indexed by two special integers q and p would be the brightest and the spectra whose positions were decided by successive FC(n) integers and were perfect self-similar without considering the dispersive effect of the refractive index on SHL. The effect of the vacancies
for some special spectral lines was also studied generally. The analytic results were confirmed by the numerical simulations.
Received 26 October 1999 and Received in final form 6 January 2000 相似文献
190.
THE RAMAN SCATTERING OF CARBON NANOTUBES PRODUCED IN DIFFERENT INERT GASES AND THEIR PRESSURES BY ARC DISCHARGE 下载免费PDF全文
First- and second-order Raman spectra of carbon nanotubes produced in helium and argon atmospheres at a pressure ranging from 11 to 92 kPa by arc discharge have been measured and compared with each other. The position and bandwidth of the spectral lines depend on the kind of inert gases and their pressure. The Raman spectra of the nanotubes produced in argon gas atmosphere are much more similar to that of polycrystalline graphite than those of the nanotubes produced in helium gas atmosphere. The position and bandwidth of nanotube Raman peaks change with gas pressure in arc discharge because different diameter distribution of nanotubes is produced at different inert gas pressure. The Raman spectra of nanotubes produced at high pressure is much more like that of graphite than those produced in lower pressure 相似文献