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Dynamical Process of Dissociation of Excitons in Polymer Chains with Impurities

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Chinese Physics Letters 2011年第9期28卷 221-224页

作者： zhao hong-xia zhao Hui CHEN Yu-Guang Department of Physics Tongji UniversityShanghai 200092

Within an extended Su–Schrieffer–Heeger model including impurity interactions,the dynamical process of exciton dissociation in the presence of an external electric field is investigated by using a non-adiabatic evolution *** the action of impurities,the stability as well as the effective mass of the exciton is *** results show that the field required to dissociate the excitons depends sensitively on the strength of the impurity *** the impurity potential strength increases,the dissociation field decreases *** theoretical results are expected to provide useful predictions concerning which polymers with properly impurity-assisted interactions are likely to be more suitable for use in organic solar cells.

关键词： potential method dissociation

Higher-Order Lagrangian Equations of Higher-Order Motive Mechanical System

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Communications in Theoretical Physics 2008年第2期49卷 479-481页

作者： zhao hong-xia MA Shan-Jun SHI Yong College of Physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China

In this paper, if the condition of variation δt = 0 is satisfied, the higher-order Lagrangian equations and higher-order Hamilton＇s equations, which show the consistency with the results of traditional analytical mechanics, are obtained from the higher-order Lagrangian equations and higher-order Hamilton＇s equations. The results can enrich the theory of analytical mechanics.

关键词： higher-order Lagrange function Hamilton function higher-order Lagrangian equation

Causes for the Unimodal Pattern of Leaf Carbon Isotope Composition in Abies faxoniana Trees Growing in a Natural Forest along an Altitudinal Gradient

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Journal of Mountain Science 2015年第1期12卷 39-48页

作者： zhao hong-xia DUAN Bao-li LEI Yan-bao Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences

Leaf morphological and physiological traits of Abies faxoniana growing in a natural forest along an altitudinal gradient were measured with the aim to identify the central mechanism for the marked variation in foliar δ13C determined by an isotope ratio mass spectrometer. There is a unimodal pattern of plant functional traits in these temperate and semi- humid areas. Stomatal parameters, specific leaf area, and C/N ratio increased, whereas C, N and δ13C values decreased with increasing altitude below 3000 m a.s.1. In contrast, they exhibited opposite trends above 3000 m a.s.l.. Our results demonstrated that high-altitude plants achieve higher water use efficiency （WUE） at the expense of decreasing nitrogen use efficiency （NUE）, whereas plants at 3000 m can maintain a relatively higher NUE but a lower WUE. Such intra-specific differences in the trade-off between NUE and WUE may partially explain the altitudinal distribution of the plants in relation to moisture and nutrient availability. Our results clearly indicate that the functional relations between nutritional status and the structure of leaves are responsible for the altitudinal variations associated with δ13C. The pivotal role of specific leaf area in regulating plant adaptive responses provides a potential physiological mechanism for the observed growth advantage of populations occupying the medium altitude. These adaptive responses altitudinal gradients showed that an altitude to of approximately 3000 m a.s.1, is the optimum distribution zone for A. faxoniana, allowing the most vigorous growth and metabolism. These results improve our understanding of the various roles of environmental and biotic variables upon δ13C dynamics and provide useful information for subalpine coniferous forest management.

关键词： Abiesfaxoniana Age Altitude Carbonisotope ratio Nitrogen content

Nuclear apoptosis induced by isolated mitochondria

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Cell Research 2000年第3期10卷 221-232页

作者： JIANG ZHENG FAN, YUN zhao, xia hong, Zhong HE ZHAI (College of Life Sciences, Peking University, Beijing, 100871 China) College of Life Sciences Peking University Beijing China

We isolated and purified mitochondria from mouse livers and spinach leaves. When added into egg extracts of Xenopus laevis, they caused nuclei of mouse liver to undergo apoptotic changes. Chromatin condensation, margination and DNA ladder were observed. After incubating isolated mitochondria in some hypotonic solutions, and centrifuging these mixtures at high speed, we got mitochondrial supernatants. It was found that in the absence of cytosolic factor, the supernatant alone was able to induce apoptotic changes in nuclei. The effective components were partly of protein. DNA fragmentation was partly inhibited by caspase inhibitors AC-DEVD-CHO and AC- YVADCHO. Meanwhile, caspase inhibitors fully blocked chromatin condensation. Primary characterization of the nuclear endonuclease(s) induced by mitochondrial supernatants was also conducted. It was found that this endonuclease is different from endonuclease G, cytochrome c-induced nuclease, or Ca2+-activated endonuclease.

关键词： Mitochondria supernatant apoptosis egg ex- tract nuclei DNA cleavage.

载药壳聚糖/羟基磷灰石复合材料在骨组织工程中的研究进展

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功能材料 2014年第13期45卷 13006-13012,13020页

作者：赵宏霞广东工业大学轻工化工学院广州510006

载药壳聚糖/羟基磷灰石(chitosan/hydroxyapatite,CS/HA)复合材料是一种兼有药物缓释和骨缺损修复双重功能的新型骨组织工程材料,近年来引起了广泛的研究兴趣。从载药CS/HA复合材料的制备方法、缓释能力、载药类型、药物对材料的性能影... 详细信息

载药壳聚糖/羟基磷灰石(chitosan/hydroxyapatite,CS/HA)复合材料是一种兼有药物缓释和骨缺损修复双重功能的新型骨组织工程材料,近年来引起了广泛的研究兴趣。从载药CS/HA复合材料的制备方法、缓释能力、载药类型、药物对材料的性能影响以及研究动向等方面做一综述。

关键词：壳聚糖羟基磷灰石载药系统骨组织工程

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一种红外波段多波长吸收器优化设计

光电子．激光 2021年第2期32卷 116-121页

作者：赵洪霞宁波工程学院电子与信息工程学院浙江宁波315016

本文设计了一种石墨烯/交替光栅/铝(Al)底板结构红外波段电磁超材料多波长吸收器。利用时域有限差分法(FDTD)数值模拟了石墨烯层厚度和光栅结构参数对吸收光谱的影响规律。研究结果证明,基于FP腔共振和相消干涉形成的吸收光谱对石墨烯... 详细信息

本文设计了一种石墨烯/交替光栅/铝(Al)底板结构红外波段电磁超材料多波长吸收器。利用时域有限差分法(FDTD)数值模拟了石墨烯层厚度和光栅结构参数对吸收光谱的影响规律。研究结果证明,基于FP腔共振和相消干涉形成的吸收光谱对石墨烯层厚度和光栅高度较敏感,即随着石墨烯层厚度增大或光栅高度降低,左边频迅速蓝移,伴随各干涉峰峰位波长小幅右飘,吸收率大幅提升;而随着光栅周期缩小,左边频吸收峰呈现右移趋势,但各干涉峰峰位几乎无变化。与此同时各干涉峰峰位波长具有随环境折射率增大线性红移的特性,故而可用于折射率或液体、气体浓度的高灵敏度感测。

关键词：吸收器多波长共振波长吸收率

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一维扩展离子Hubbard模型的相图研究

物理学报 2015年第10期64卷 213-218页

作者：赵红霞赵晖陈宇光鄢永红同济大学物理科学与工程学院上海200092 绍兴文理学院绍兴312000

应用密度矩阵重整化群方法,研究了存在交错离子势△时一维半满扩展Hubbard模型的相图.通过计算关联函数、结构因子、位置算符等方法,描绘了从Mott绝缘体-键有序绝缘体-Band绝缘体的特性并给出了精确的相边界.研究发现:中间的键有序绝缘... 详细信息

应用密度矩阵重整化群方法,研究了存在交错离子势△时一维半满扩展Hubbard模型的相图.通过计算关联函数、结构因子、位置算符等方法,描绘了从Mott绝缘体-键有序绝缘体-Band绝缘体的特性并给出了精确的相边界.研究发现:中间的键有序绝缘体相在相图中占据了很小的一部分区域,当存在离子势△的情况下,这个区域将会有所增大;而当相互作用足够强时,这个中间相消失.给出了离子Hubbard模型(最近邻电子-电子相互作用=0)的相图.

关键词：密度矩阵重整化群 Hubbard模型量子相变相图

Stress-transfer characteristics of embedded fiber Bragg grating sensors

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Optoelectronics Letters 2005年第3期1卷 168-171页

作者： BAO Ji-long CHEN Ying zhao hong-xia College of Electronic and Information Engineering Ningbo University of Technology Ningbo 315016 China

The shear lag theory is used to analyze the stress transfer from concrete matrix to FBG sensors based on that the FBG sensor and the concrete matrix are composite. The stress transfer formula and the coefficient are obtained. The experiments prove that the theoretical results of the stress transfer by the stress transfer formula are in well agreement with the experimental data.

关键词：光学传感器光栅压力转移 FBG传感器

小波分析与蚁群神经网络5′-硝基水杨基荧光酮分光光度法同时测定钨钼锑

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冶金分析 2010年第5期30卷 19-23页

作者：赵红霞攀钢集团设计研究院有限公司

提出了钨、钼、锑—5′-硝基水杨基荧光酮—CTMAB的新显色体系,并用于钨、钼、锑三组分光度分析。为解析钨、钼和锑的重叠光谱,提高多组分同时测定的准确度,将蚁群神经网络(ACAN)与小波分析相结合,建立一种利用小波变换提取重叠光谱信息... 详细信息

提出了钨、钼、锑—5′-硝基水杨基荧光酮—CTMAB的新显色体系,并用于钨、钼、锑三组分光度分析。为解析钨、钼和锑的重叠光谱,提高多组分同时测定的准确度,将蚁群神经网络(ACAN)与小波分析相结合,建立一种利用小波变换提取重叠光谱信息,再用蚁群神经网络解析的方法,此方法应用于合金钢标准样品中钨、钼、锑多组分同时测定,测定值与认定值相符,相对误差分别为0.14%、0.13%、0.013%。

关键词：分光光度法多组分蚁群神经网络小波变换