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Effects of pH on the peripheral light-harvesting antenna complex for Rhodopseudomonas palustris

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science china(life sciences) 2008年第8期51卷 760-766页

作者： FENG Juan, li XueFeng & liU Yan school of life science and technology, {6., Chengdu 610054, china school of life science and technology University of Electronic Science and Technology of China Chengdu China

In this work steady-state absorption spectroscopy, circular dichroism spectroscopy and sub-micro-second time-resolved absorption spectroscopy were used to investigate the effect of pH on the struc-tures and functions of LH2 complex for Rhodopseudomonas palustris. The results revealed that: (1) B800 Bchla was gradually transformed to free pigments absorbing around 76. nm on the minutes timescale upon the induction of strong acidic pH, and subsequently there disappeared the CD signal for Qy band of B800 in the absence of B800. In addition, Carotenoids changed with the similar tendency to B850 BChl. (2) The introduction of strong basic pH gave rise to no significant changes for B800 Bchla, while B850 BChla experienced remarkable spectral blue-shift from 852 to 837 nm. Similar phe-nomenon was seen for the CD signal for Qy band of B850. Carotenoids displayed strong and pH-independent CD signals in the visible range. (3) In the case of both physiological and basic pH, broad and asymmetrical positive Tn←T1 transient absorption appeared following the pulsed photo-excitation of Car at 532 nm. By contrast, the featureless and weak positive signal was observed on the sub-microsecond timescale in the acidic pH environment. The aforementioned experimental results indicated that acidic pH-induced removal of B800 Bchla prevented the generation of the caro-tenoid triplet state (3Car*), which is known to be essential for the photo-protection function. Neverthe-less, carotenoids can still perform this important physiological role under the basic pH condition, where the spectral blue shift of B850 exerts little effect on the overall structure of the cyclic aggregate, therefore favoring the formation of carotenoid triplet state.

关键词： pH-induced B800-removal triplet state photo-protection function

Hybrid of comprehensive learning particle swarm optimization and SQP algorithm for large scale economic load dispatch optimization of power system

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science china(Information sciences) 2010年第8期53卷 1566-1573页

作者： WANG Yu , li Bin & YUAN Bo Department of electronic science and technology, school of Information science and technology, university of science and technology of china, Hefei 230027, china Department of electronic science and technology School of Information Science and Technology University of Science and Technology of China

Economic load dispatch (ELD) is an important optimization task in power systems. In the previous works, various researchers attempted to address this problem by both mathmatical and heuristic optimization algorithms. However, there are still two practically important issues that have not attracted sufficient attention: 1) the stability of these algorithms cannot be effectively ensured; 2) the performance of these algorithms on large scale ELD optimization tasks remains to be unsatisfactory. CLPSO is an effective global optimization algorithm. To strengthen the convergence ability of CLPSO, the sequential quadratic programming (SQP) is introduced into it. This results in a new algorithm hybrid of comprehensive learning particle swarm optimization and sequential quadratic programming (SQP-CLPSO). To assess the performance of SQP-CLPSO, it is compared with several state-of-the-art evolutionary algorithms (EAs) on the classical ELD optimization problems. Experimental results show that SQP-CLPSO has very good abilities of convergence, diversity maintainence and scalability, which make it suitable for complex ELD problems.

关键词： particle swarm optimization comprehensive learning particle swarm optimization sequential quadratic programming local search power systems economic load dispatch

Construction of a multidimensional plane network-on-chip architecture based on the hypercube structure

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Progress in Natural science:Materials International 2009年第5期19卷 635-641页

作者： Chang Wu, Yubai li, Qicong Peng, Song Chai, Zhongming Yang DSP Lab, school of Communication and Information Engineering, university of electronic science and technology of china, Chengdu 610054, china DSP Lab School of Communication and Information Engineering University of Electronic Science and Technology of China Chengdu 610054 China

In current network-on-chip (NOC) studies and in practical applications, the mesh structure is the most widely used and deeply researched structure. However, the hypercube structure is more symmetrical and regular than the mesh or torus structures. This paper compares the network characteristics of these three direct topologies and proposes a method to compress the hypercube into a plane structure. This structure, which has the multidimensional property based on the hypercube, is called the multidimensional plane (MDP) NOC. The compression process is divided into two steps: the transformation of router denotations and the connection of channels. Then, SystemC is used to implement the MDP NOC and it is compared with the mesh and torus NOCs in terms of four aspects of performance, including average latency time, normalization throughput, energy consumption and area cost.

关键词： NOC Hypercube Dimension SystemC Simulation

Electrochemical Characteristic of Decarburization Reaction

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 27-30页

作者： Xionggang Lu Fushen li lifen li Kouchih Chou (Applied science school, {6. of science and technology Beijing, Beijing 100083, china)(Material science and Engineering school, Shanghai {6., Shanghai 200072, china) Applied science school University of Science and Technology Beijing Beijing 100083 China Material science and Engineering school Shanghai University Shanghai 200072 China

The electrochemical mechanism of the reaction between Fe-C melts and CaO-SiO2-Al2O3-FeOx slag systems has been carried out. The experimental results suggest that the final content of carbon in melt increases as the partial oxygen pressure of gas decreases no matter whether there is electronic conductor or not. However, the final content of carbon in the system with electronic conductor is much lower than that without electronic conductor. It can be deduced that the transfer ability of oxygen in slag is dominated by electrons. When an electronic conductor exists, an easy pathway for the electrons is provided and the oxygen transfer rate is accelerated.

关键词： melt-slag reaction decarburization electrochemistry electronic conductor

Research and Development of Enterprise Information Visual Management System Based on GIS

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武汉理工大学学报 2006年第S1期28卷 339-343页

作者： YANG liqing,li Xunbo (school of Mechatronics Engineering,university of electronic science and technology of china,Chengdu 610054, china) school of Mechatronics Engineering University of Electronic Science and Technology of ChinaChengdu 610054China

Aiming at managing enterprise information,we have done research and development on enterprise information visual management system based on geographic information system (GIS). In this paper,basis function,design scheme and implement are introduced. Space data and attribute data are supervised with a database. And the functions of GIS,such as display,edit and print,are utilized. The map information and the enterprise information are visually managed and integrally supervised.

关键词： GIS enterprise information management visualization

A new satellite to satellite tracking algorithm from Doppler-shifted frequency measurements

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Progress in Natural science:Materials International 2007年第10期17卷 1226-1234页

作者： li Qiang, Guo Fucheng and Zhou Yiyu(school of electronic science & Engineering, National university of Defense technology, Changsha 410073, {6.) school of electronic science & Engineering National University of Defense Technology Changsha 410073 China

A new satellite to satellite tracking (SST) algorithm from Doppler-shifted frequency measurements is proposed. The estimation principle is demonstrated and the mathematic model of SST is established. The state estimation methods for a user (the cooperative case) and target satellites (the non-cooperative case) are presented based on particle swarm optimization (PSO). The Cramer-Rao lower bounds (CRLB) are deduced as well. Performance of the new algorithm is validated through computer simulations, which proved that the proposed method is effective in terms of the estimation quality compared with CRLB and superior in accuracy to the Bearings-Only (BO) method in almost all simulation cases except for the case that an enough long tracking arc-length is obtained for a user satellite.

关键词： satellite to satellite tracking (SST) Doppler-shifted frequency (DSF) Space Surveillance Network (SSN) particle swarm optimization (PSO).

Analysis of forest backscattering characteristics based on polarization coherence tomography

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science china(Technological sciences) 2010年第S1期53卷 166-175页

作者： LUO HuanMin 1,li XiaoWen 1,2,CHEN ErXue 3,CHENG Jian 4 & CAO ChunXiang 21 Institute of Geo-Spatial Information science and technology,university of electronic science and technology of china,Chengdu 610054,china 2 State Key Laboratory of Remote Sensing science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of sciences and Beijing Normal university,Beijing 100101,china 3Institute of Forest Resources Information Technique of Chinese Academy of Forestry,Beijing 100091,china 4 school of electronic Engineering,university of electronic science and technology of china,Chengdu 610054,china Institute of Geo-Spatial Information science and technology University of Electronic Science and Technology of China Chengdu China State Key Laboratory of Remote Sensing science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Institute of Forest Resources Information Technique of Chinese Academy of Forestry Beijing China school of electronic Engineering University of Electronic Science and Technology of China Chengdu China

It is difficult to make an inventory of vertical profiles of forest structure parameters in field ***,analysis and understanding of forest backscattering characteristics contribute to estimation and detection of forest vertical structure because of the close relationships between backscattering characteristics and structure *** vertical structure function in the complex interferometric coherence definition,which represents the vertical variation of microwave scattering with the penetration depth at a point in the 2-D radar image and can be used to analyze the forest backscattering characteristics,can be reconstructed from polarization coherence tomography(PCT).Based on PCT,the paper analyzes the forest backscattering characteristics and explores the inherent relationship between the result of PCT and the forest structure parameters from numerical simulation of Random Volume over Ground model(RVoG),Polarimetric SAR interferometry(PolinSAR)simulation of forest scene and PolinSAR data at L-band of the test site ***,the effects of the extinction coefficient and surface-to-volume scattering ratio in RVoG model on vertical backscattering characteristics are analyzed by means of numerical ***,by applying PCT to L-band POlinSAR simulations of forest scene,different variations of vertical backscattering due to different extinction coefficients and the ratios of surface-to-volume scattering resulting from different polarizations,forest types and densities are displayed and *** a concept of relative average backscattering intensity is presented,and the factors which affect its vertical distribution are also *** results show that there is high sensitivity of the vertical distribution of forest relative average backscattering intensity to the polarization,forest type and ***,based on repeat pass DLR E-SAR L-band airborne POlinSAR data,the capability of PCT technology for detection

关键词： backscattering characteristic POlinSAR PCT vertical structure function

Kinetics analysis of volume phase transition of intelligent neutral thermo-sensitive hydrogels

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science china(Physics,Mechanics & Astronomy) 2008年第5期51卷 532-540页

作者： WANG XiaoGui1 & li YiQuan2 1 College of Mechanical Engineering,Zhejiang university of technology,Hangzhou 310032,china 2 school of Mechanical & electronic Engineering,Changchun university of science and technology,Changchun 130022,china College of Mechanical Engineering Zhejiang University of Technology Hangzhou China school of Mechanical & electronic Engineering Changchun University of Science and Technology Changchun China

In this work,utilizing the first law of thermodynamics and the Flory mean-field theory,the kinetic deformation studies concerning the volume phase transition of the neutral thermo-sensitive hydrogels were performed *** hydrogel was assumed as a biphasic mixture medium in the framework of the continuum mixture *** the energy conservation of the thermodynamics system of the hydrogel,the governing equations for the kinetics of the nonlinear large deforma-tion were *** explicit analytical expressions of the effective stress tensor and the chemical potential of the fluid of the thermo-sensitive hydrogel PNIPA were also obtained from the Helmholtz free energy,which can model the steady-static volume phase transition quantitatively.

关键词： thermo-sensitive hydrogel volume phase transition effective stress energy conservation

PLGA nanoparticle encapsulated paclitaxol for sustained release and its anticancer effect for HeLa cells in vitro

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生物物理学报 2009年第S1期25卷 298-299页

作者： Hong Yang, Kai li, Zhonghua liu, Zhenglong Ren, Yiyao liu , Department of Biophysics, school of life science and {6., university of electronic science and technology of china, Chengdu, Sichuan 610054, P.R.china

Poly (D,L-lactide-co-glycolide) (PLGA) is a biodegradable and biocompatible polymer material for drug deliver system. The aim of this study is to synthesize drug-loaded

关键词： PLGA nanoparticle encapsulated paclitaxol for sustained release and its anticancer effect for HeLa cells in vitro