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A study of phosphate adsorption by different temperature treated hydrous cerium oxides

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Rare Metals 2011年第1期30卷 58-62页

作者： GUO Huichao LI Wenjun WANG Huanying ZHANG Jinghua LIU Yang ZHOU Yue School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China School of Applied science University of Science and Technology Beijing Beijing 100083 China beijing center for Physical and Chemical Analysis Beijing 100089 China

An alkaline precipitation method was introduced to produce hydrous cerium *** prepared powder was characterized by Brunauer-Emmett-Teller（BET） nitrogen adsorption-desorption,X-ray diffraction（XRD）,Fourier transform infrared（FTIR） spectrometry,and thermal gravimetry（TG） *** adsorbent has a chemical formula of CeO2·nH2O（n 2） and a cubic fluorite-type structure after high temperature *** capacity of different temperature treated hydrous cerium oxides does not directly correlate with BET specific surface *** adsorption isotherms follow the Langmuir equation below the treatment temperature of 800°*** adsorption causes no change on the structure of a hydrous cerium oxides,and no signs of CePO4 precipitates are *** ion-exchanging structure of hydrous cerium oxide plays a fundamental role in phosphate *** structure is highly temperature resistant and forms adsorption sites which adsorb both water and some *** loss of adsorption ability cannot be achieved unless the treatment temperature is higher than 1200°*** study shows that the adsorption of phosphates is mainly an anion-exchange process.

关键词： phosphates adsorption cerium compounds hydroxyl group ion exchange

RRM:An incentive reputation model for promoting good behaviors in distributed systems

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science in china(Series F) 2008年第11期51卷 1871-1882页

作者： ZHANG Hong1,2,DUAN HaiXin1,3 & LIU Wu1,3 1 Tsinghua national Laboratory for Information science and technology,Tsinghua university,beijing 100084,china 2 Department of Computer science and technology,Tsinghua university,beijing 100084,china 3 Network Research center,Tsinghua university,beijing 100084,china Tsinghua national Laboratory for Information science and technology Tsinghua University Department of Computer science and technology Tsinghua University Network Research center Tsinghua University

Reputation systems represent soft security mechanisms that complement traditional information security mechanisms. They are now widely used in online e-commerce markets and communities in order to stimulate good behaviors as well as to restrain adverse behaviors. This paper analyzes the limitations of the conversational reputation models and proposes an incentive reputation model called the resilient reputation model （RRM） for the distributed reputation systems. The objective of this reputation model is not only to encourage the users to provide good services and, therefore, to maximize the probability of good transaction outcomes, but also to punish those adverse users who are trying to manipulate the application systems. The simulation results indicate that the proposed reputation model （RRM） could effectively resist against the common adverse behaviors, while protecting the profits of sincere users from being blemished by those adversaries.

关键词： reputation model distributed system trust soft security

Subchronic toxicological effects of aquatic nitrobenzene on Medaka and Chinese rare minnow

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science china Chemistry 2007年第5期50卷 707-717页

作者： ZHOU QunFang1, FU JianJie1,2, MENG HaiZhen1,2, ZHU XueYan1,2, JIANG GuiBin1, ZHANG JianBin1, LIU JieMin2 & SHI GuoQing2 1 State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research center for Eco-environmental sciences, Chinese Academy of sciences, beijing 100085, china 2 Department of Chemistry, School of Applied science, university of science and technology beijing, beijing 100083, china State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing China Department of Chemistry School of Applied Science University of Science and Technology Beijing Beijing China

Based on the simulative exposure experiments of nitrobenzene to two small experimental fishes, Medaka (Oryzias latipes) and Chinese Rare Minnow (Gobiocypris rarus), it was found that nitrobenzene could decrease in a linear way in the static aquatic system. Both fishes could accumulate dose-related levels of nitrobenzene quickly and eliminate the compound rapidly when they were transferred to clean water. The Chinese rare minnow showed more sensitivity to the acute toxicity exposure of nitrobenzene than Medaka. Typical molecular biomarkers in oxidative defense system including superoxide dismu- tase (SOD), catalase (CAT) showed the chemical induced alterations. The changes of acetylcholi- nesterase (AChE) activities indicated that nitrobenzene might affect the normal neural function. Nitro- benzene exposure could also lead to obvious damaging effects on the target organs, such as gill and liver by hitopathological studies.

关键词： nitrobenzene, Medaka, Chinese rare minnow, bioaccumulation, elimination, molecular biomarkers, histopathological effects

Study on Transformation of CaO-Al_2O_3-SiO_2-MgO System Inclusions in ZG06Cr13Ni4Mo Stainless Steel

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Journal of Iron and Steel Research International 2011年第S2期18卷 341-346页

作者： LIU Jian-hui1,3, DONG Han1,3, ZHU Rong2, LI Shi-qi2 (1. Institute for Structural materials,Central Iron and Steel Research Institute, beijing 100081,china 2. School of Metallurgical and Ecological Engineering,university of science and technology beijing, beijing 100083,china 3. national Engineering Research center of Advanced Steel technology, beijing 100081,china) Cent Iron & Steel Res Inst Inst Struct Mat Beijing 100081 Peoples R China Natl Engn Res Ctr Adv Steel Technol Beijing 100081 Peoples R China Univ Sci & Technol beijing Sch Met & Ecol Engn Beijing 100083 Peoples R China

This paper aims at generally studying on the inclusions of ZGG06Cr13Ni4Mo ultra-low carbon stainless steel used for large scale hydraulic turbine sets. On the basis of analysis the industrial test samples, thermodynamic software FactSage is used to study inclusions transformation process in CaO-SiO2-Al2O3-MgO system while stainless steel is been smelting. The results illustrate the inclusions melting points and plasticity variation law. The reasonable inclusions plasticity controlling area is found out in low melting point. The melting point is up to 1280℃ While MgO weight concentration is 10% in CaO-SiO2-Al2O3-MgO system, SiO2, Al2O3 and CaO in inclusions are in weight concentration range of 50-70%, 10-20% and 10-40%, respectively. For purpose of gaining low melting point inclusions, silicon alumina radio in deoxidant should be controlled between 2-5 for ultra-low carbon stainless steel refining in industry.

关键词： ZG06Cr13Ni4Mo stainless steel low melting point inclusion thermodynamic calculation

Preparation of CuInSe_2 films by ultrasonic electrodeposition-selenization and the improvement of their surface morphology

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Rare Metals 2010年第5期29卷 519-523页

作者： WANG Yanlai NIE Hongbo GUO Shiju Key Laboratory of Semiconductor Photovoltaic technology at Universities of Inner Mongofia Autonomous Region School of Physical Science and Technology lnnerMongolia University Hohhot 010021 China china national R＆D center for Tungsten technology .Yiamen 361006 China School of materials science andEngineering University of Science and Technology Belting Beifing 100083 China

The CulnSe2 compound was prepared by selenization of Cu-In precursor, which was ultrasonic electrodeposited at constant current. CulnSe2 films were compacted to improve surface morphology. The films were characterized by X-ray diffractometry （XRD）, scanning electron microscopy （SEM）, and energy dispersive spectroscopy （EDS）. It is indicated that ideal stoichiometrie CulnSe2 films can be obtained by the selenization of Cu-In precursor deposited at a current density of 20 mA/cm^2. Single-phase CulnSe2 is formed in the selenization proeess, and it exhibits preferred orientation along the （112） plane. The CulnSe2 films with smooth surface can be obtained under the pressure of 500 MPa at 60℃.

关键词： photovoltaic cells CulnSe2 thin films electrodeposition selenization compaction

Spray and forward:Efficient routing based on the Markov location prediction model for DTNs

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science china(Information sciences) 2012年第2期55卷 433-440页

作者： DANG Fei1,YANG XiaoLong1,2 & LONG KePing2 1 Research center for Optical Internet and Mobile Information Networks(COIMIN),university of Electronic science and technology of china,Chengdu 611731,china 2 School of Computer and Communications Engineering,university of science and technology beijing,beijing 100083,china Research center for Optical Internet and Mobile Information Networks (COIMIN) University of Electronic Science and Technology of China School of Computer and Communications Engineering University of Science and Technology Beijing

Typical delay tolerant networks(DTNs)often suffer from long and variable delays,frequent connectivity disruptions,and high bit error *** DTNs,the design of an efficient routing algorithm is one of the key *** existing methods improve the accessibility probability of the data transmission by transmitting many copies of the packet to the network,but they may cause a high network *** address the tradeoff between a successful delivery ratio and the network overhead,we propose a DTN routing algorithm based on the Markov location prediction model,called the spray and forward routing algorithm(SFR).Based on historical information of the nodes,the algorithm uses the second-order Markov forecasting mechanism to predict the location of the destination node,and then forwards the data by greedy routing,which reduces the copies of packets by spraying the packets in a particular *** contrast to a fixed mode where a successful-delivery ratio and routing overhead are contradictory,a hybrid strategy with multi-copy forwarding is able to reduce the copies of the packets efficiently and at the same time maintain an acceptable successful-delivery *** simulation results show that the proposed SFR is efficient enough to provide better network performance than the spray and wait routing algorithm,in scenarios with sparse node density and fast mobility of the nodes.

关键词： delay tolerant networks spray and forward Markov position prediction routing algorithm

Research on Control of Electric Power Steering System with Intelligent Feedforward

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Research on Control of Electric Power Steering System with I...

A measurement error model for microarray data analysis

2010 Chinese Control and Decision Conference

作者： Weidong Zhang~1,Yibo Ai~2 1.national center for materials service safety,university of science & technology beijing,100083 2.national center for materials service safety,university of science & technology beijing,100083

＜正＞Electric power steering system（EPS） develops with the automobile entering the people’s *** can alleviate people’s burden from operation,make people have more energy to make decision and tackle various operation conditions,and improve reliability and security of the operation *** this paper,based on a type of EPS whose motor axis is same as steering column,the authors proposed a new type EPS with intelligent feedforward（EPS-IFF）. This new system can improve efficiency and intelligence of the system,and make the output of torsion fast,accurate and *** the physical force is alleviated the intelligence expend is alleviated *** can accomplish the power assistant steering fast and accurately,and then the system capability will be improved overall.

关键词： Electric Power Steering System Feedforward Control Expert System

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Progress in Natural science:materials International 2005年第7期15卷 614-620页

作者： ZHOU Yiming and CHENG Jing ( Department of Biological sciences and Biotechnology, Tsinghua university, beijing 100084, china State Key Laboratory of Biomembrane and Membrane Biotechnology, Tsinghua university, beijing 100084, china national Engineering Research center for beijing Biochip technology, 18 Life science Parkway, beijing 102206, china) Department of Biological sciences and Biotechnology Tsinghua University Beijing 100084 China. State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing 100084 China. national Engineering Research center for beijing Biochip technology 18 Life Science Parkway Beijing 102206 China

Microarray technology has been widely used to analyze the gene expression levels by detecting fluorescence intensity in a high throughput fashion. However, since the measurement error produced from various sources in microarray experiments is heterogeneous and too large to be ignored, we propose here a measurement error model for microarray data processing, by which the standard deviation of the measurement error is demonstrated to be linearly increased with fluorescence intensity. A robust algorithm, which estimates the parameters of the measurement error model from a single microarray without replicated spots, is provided. The model and algorithm for estimating of the parameters from a given data set are tested on both the real data set and the simulated data set, and the result has been proven satisfactory. And, combining the measurement error model with traditional Z-test method, a full statistical model has been developed It can significantly improve the statistical inference for identifying differentially expressed genes.

关键词： microarray measurement error model parameter estimation differentially expressed genes.

A Control Method of Electric Power Steering System Based on Information Fusion Expert System

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A Control Method of Electric Power Steering System Based on ...