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141.
ZHANG Duan-Ming ZHONG Zhi-Cheng HAN Xiang-Yun YAN Wen-Sheng SUN Hong-Zhang YANG Feng-Xia ZHENG Ke-Yu WEI Nian LI Zhi-Hua 《理论物理通讯》2005,43(5):855-857
In this paper, the relation between the dielectric properties and the
lattice distortion in the phase coexistence region is discussed using a phase statistical distribution model, and in the rhombohedral phase region the two connection equations on the dielectric properties and the lattice distortion are established. Particularly, the relation between the dielectric properties and the lattice distortion is investigated in the phase coexistence region of PZT ceramics, and the fitting value of the volume fraction of the tetragonal phase
VT to composition x in the equation is determined. Further, the fitting results are well consistent with the related experimental data. It involves more profound physical process than relation between the dielectric properties and composition x. 相似文献
142.
We present a stochastic critical slope sandpile model, where the amount of grains that fall in an overturning event is stochastic variable. The model is local, conservative, and Abelian. We apply the moment analysis to evaluate critical exponents and finite size scaling method to consistently test the obtained results. Numerical results show that this model, Oslo model, and one-dimensional Abelian Manna model have the same critical behavior although the three models have different stochastic toppling rules, which provides evidences suggesting that Abelian sandpile models with different stochastic toppling rules are in the same universality class. 相似文献
143.
用电容平面图研究金/十八硫醇单分子膜的自组装过程和缺陷情况 总被引:1,自引:0,他引:1
推导了电化学体系中理想极化电极、电化学极化电极的复数电容表达式。根据这些表达式分析了上述体系的电容平面图 (Capacitance Plane Plot,CPP) ,利用 CPP可以方便地监测体系的电容值。用电子元件组成了上述体系的等效电路 ,测定了交流阻抗谱 ,得到了 CPP与理论推导一致。研究了金 /十八硫醇自组装膜的 CPP,根据 CPP讨论了金 /硫醇膜的组装过程及缺陷和组装时间的关系。 相似文献
144.
145.
146.
The stability of hydrogen-bonded complexes, DMF–H
n
CCl4−n
(n = 1–3), has been investigated by several theoretical methods including the MP2 level of ab initio theory at various basis
sets from 6-31+G* to 6-311++G**. Two stable configurations (respectively a and b) were obtained for each complex with no imaginary frequencies. The minimum energy structure of these complexes has also been
analyzed by means of the atoms in molecule theory at MP2/6-311++G** level. It is found that C–H···O hydrogen bonding exists
in these systems and that the intensity of HB interaction gradually increases with successive chlorination. Computed results
indicate that these complexes automatically assemble into different stable configurations. For the complexes under consideration,
their stabilities can be mainly ascribed to the intermolecular HB interaction. The present work is helpful to clearly understand
the interaction mechanism of these complexes in theory. 相似文献
147.
Average life of oxygen vacancies of quartz in sediments is estimated by using the ESR (electron spin resonance) signals of E’ centers from the thermal activation technique. The experimental results show that the second-order kinetics equation is more applicable to the life estimation compared with the first order equation. The average life of oxygen vacancies of quartz from 4895 to 4908 deep sediments in the Tarim Basin is about 1018 a at 27°C. 相似文献
148.
采用等离子增强化学气相沉积方法(PECVD)制备了微量掺碳的p型纳米非晶硅碳薄膜(p-nc-SiC:H),反应气体为硅烷和甲烷,掺杂气体采用硼烷,沉积温度分别采用333K,353K和373K.测量结果表明随着沉积温度增加和碳含量的增加,薄膜的光学带隙增加;薄膜具有较宽的带隙和较高的电导率,同时有较低的激活能(0.06eV).Raman和XRD测量结果表明薄膜存在纳米晶.优化的p型纳米非晶硅碳薄膜作为非晶硅p-i-n太阳电池的窗口层,使得太阳电池的开路电压达到0.94V.
关键词:
光学带隙
纳米硅
薄膜
太阳能电池 相似文献
149.
C. -S. Jia P. Guo Y. -F. Diao L. -Z. Yi X. -J. Xie 《The European Physical Journal A - Hadrons and Nuclei》2007,34(1):41-48
By using the basic concepts of the supersymmetric quantum mechanics formalism and the function analysis method, we solve the
Dirac equation with vector and scalar potentials and obtain the bound-state solutions for the nuclei in the relativistic P?schl-Teller
potential. All of the analyses are prepared under the conditions of the exact spin symmetry and pseudospin symmetry. The exact
energy equation and corresponding two-component spinor wave functions for s -wave bound states are obtained analytically. 相似文献
150.
X. Dai Y. Diao Q. Gu D. Han 《Proceedings of the American Mathematical Society》2002,130(11):3259-3267
Let be a real expansive matrix. We characterize the reducing subspaces of for -dilation and the regular translation operators acting on We also characterize the Lebesgue measurable subsets of such that the function defined by inverse Fourier transform of generates through the same -dilation and the regular translation operators a normalized tight frame for a given reducing subspace. We prove that in each reducing subspace, the set of all such functions is nonempty and is also path connected in the regular -norm.