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COMPARISON OF HEAVY METAL DISTRIBUTION AND BIOAVAILABILITY IN SURFACE SEDIMENTS (SSs) AND NATURAL SURFACE COATINGS (NSCs) SAMPLED FROM THE SONGHUA RIVER,northEAST OF china

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COMPARISON OF HEAVY METAL DISTRIBUTION AND BIOAVAILABILITY I...

第三世界生态高峰会

作者： Li Y~(1,2) Li N~2 energy and Environmental Research Centre,north china electric power university,beijing 102206,china 2.College of Environment and Resources Jilin university,Changchun 130012.china

Some heavy metals in aquatic environments have produced toxic and bio-accumulative effects on people's health and *** is, therefore,of great significance to reveal the transport,biogeochemistry, bioavailability,toxicity and ultimate fate of heavy metals in natural *** surface sediments(SSs)and natural surface coatings (NSCs),including biofilms and minerals associated,are thought to be the dominant determinants for the behaviours of the associated composite solid phases and play important roles in transportation and bioavailability of trace heavy metals in aquatic ***, up to now,less research was reported on the distribution and transport of trace metals in different phases and components,and in particular no investigation was focused on the distribution characteristics of heavy metals in different SSs and NSCs *** view of the current concern over metal distribution characteristics,it is of considerable interest to understand the relative contents of heavy metals in different solid phases and main chemical *** elements(iron, manganese,copper,zinc and lead)in 3 SSs/NSCs sampling locations were investigated with the modified sequential extraction procedure (MSEP)to compare the metal distribution and bioavailability in the two solid *** results indicated that Cu was present mainly in the organic matter fraction:Zn and Pb were dominantly associated with Fe oxides;the dominant proportion of Fe was in the residual fraction. while Mn was existed significantly as non-residual fractions(Fig.1). Fe oxides and Mn oxides were relatively dominating fractions compared with organic matter fractions for the metals of Cu,Zn and Pb There were much more levels of metals in the non-residual fractions, *** bioavailable speciation,in NSCs compared with *** distributions of Cu,Zn and Pb in the residual fraction,Zn and Pb in the organic matter fraction were found significant correlation with total organic carbon(TOC),and

关键词： Surface sediments Natural surface coatings Heavy metal bioavailability

Discussion　on　the　Network　Method　for　Calculating　Radiant　Interchange　Within　an　Enclosure

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Journal of Thermal Science 1994年第2期3卷 130-135页

作者： H.J. Kang W.Q. Tao(school of energy and power engineering, Xi’an Jiaotong university, Xi’an, Shaanxi 710049, china) 1. school of energy and power engineering Xi’an Jiaotong University 710049 Xi’an Shaanxi China

In this paper the △- Y transformation of a linear electric circuit is introduced to simplify the computation of net radiant heat exchange on a surface of an enclosure with three surfaces. The illustration of the transformation is given by solving six problems taken from the textbooks. Some discussion concerning the possibility of extending the transformation method to enclosures with more than three surfaces, and the condition for applying the network method are also presented.

关键词： radiative heat transfer network method enclosure.

Performance of electric Double Layer Capacitors using Active Carbons Prepared from Petroleum Coke by KOH and Vapor Re-Etching

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Journal of Materials Science & Technology 2003年第3期19卷 265-269页

作者： Xiaofeng WANG, Dazhi WANG Ji LIANGDepartment of Mechanical engineering, Tsinghua university, beijing 100084, china Tsinghua Univ Dept Mech Engn Beijing 100084 Peoples R China

The electrochemical storage of energy in a special kind of active carbon materials used as capacitor electrodes is considered. Petroleum coke was used for preparation of carbons with different porosities by KOH and vapor etching with catalysis of FeCI3 in turn. Carbon electrodes were fabricated and used as electrodes of double layer capacitors. Nitrogen adsorption was used to characterize the porous structure of the carbons. The electrochemical performance of the capacitors in 6 mol/L KOH was investigated with constant current charge and discharge experiments. A specific capacitance larger than 160 F/g was achieved with an electrode composed of 75% active carbon with a specific surface area of 1180 m2/g and 20% graphite as conductive agent. Evaluation of capacitor performance was conducted by different techniques, e.g. voltammetry and impedance spectroscopy. Characteristics of the capacitor were also discussed. A hybrid power source consisting of nickel- hydrogen and double layer capacitor was demonstrated by powering successfully a simulated power load encountered in communication equipment.

关键词： Activated carbon Re-etching Double layer capacitor Supercapacitor

Introduction to school of Environmental Science and engineering of north china electric power university

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electricity 2010年第2期21卷 50-51页

作者： Zhao Yi, Ma Shuangchen school of Environmental Science and engineering, north china electric power university school of Environmental Science and engineering North China Electric Power University

Along with the fast development of national economy, environmental issues have become more and more prominent. china has promulgated a series of policies of energy-saving and emission-reduction to

关键词： school Introduction to school of Environmental Science and engineering of north china electric power university

Effect of the Sputtering Parameters on the Structure and Properties of Cu_3N Thin Film Materials

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Journal of Wuhan university of Technology(Materials Science) 2010年第6期25卷 935-937页

作者：钱显毅黄致新 school of Electronic Information & electric engineering Changzhou Institute of Technology College of Physical Science and Technology Cental China Normal University

Copper nitride （Cu3N） thin films were successfully deposited on glass substrates by reactive radio frequency magnetron *** effects of sputtering parameters on the structure and properties of the films were *** experimental results show that with increasing of RF power and nitrogen partial pressure,the preferential crystalline orientation of Cu3N film is changed from （111） to （100）.With increasing of substrate temperature from 70 ℃ to 200 ℃,the film phase is changed from Cu3N phase to *** increasing sputtering power from 80 W to 120 W,the optical energy decreases from 1.85 eV to 1.41 eV while the electrical resistivity increases from 1.45 ×102 Ω·cm to 2.99×103 Ω·cm,respectively.

关键词： copper nitride sputtering parameters structure electrical and optical properties

Predictive Control for DFIG-Based Wind power Generation

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Predictive Control for DFIG-Based Wind Power Generation

第24届中国控制与决策会议

作者： Xiao-Bing Kong, Lin Wang, Xiang-Jie Liu The State Key Laboratory of Alternate electrical power System with renewable energy Sources, north china electric power university, beijing 102206

Reliable control of the doubly fed induction generator （DFIG） is necessary to ensure high efficiency and high load-following capability in the operation of modern wind power plant. This is often difficult to achieve using conventional linear controllers, as wind power plants contain many uncertainties. This paper proposes a predictive controller for a power control of DFIG. The control is derived by optimization of an objective function that considers the tracking factors under realistic constraints. The prediction was calculated based on the DFIG model. Simulation results are presented to validate the proposed controller, the effectiveness of the proposed method.

关键词： Doubly fed induction generator predictive control power control Wind energy

Wind and Solar energy Combining with Reverse Osmosis System for Brackish Water Desalination

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Wind and Solar Energy Combining with Reverse Osmosis System ...

2012年环境污染与大众健康学术会议

作者： Qi Houbo 1 , Zhang Pan 2 , Hu Jingtao 2 , Zhou Ting 2 ,Li Wei 2 1 school of Nuclear Science and engineering, north china electric power university, beijing, china 2 Sino-Canada Resources and Environmental Research Academy, north china electric power university, beijing, china

Solar and wind energy could be used as a means for reverse osmosis desalination as the drive. In this paper some attempts have been made to present some work of the highlights that are important efforts around the world in the field of renewable energy for RO system. In addition, the weakness of solar and wind power is intermittently, therefore batteries are necessary. Both of the energy can be transferred into electricity and then could be the power of the pump, so the pump is the bridge between the renewable energy and the reverse osmosis module. Moreover, response surface methodology （RSM） has been used to develop the predictive model especially for the feed pressure condition.

关键词： Wind and solar energy Reverse osmosis Desalination Response surface methodology

基于两级模糊综合评判的输变电工程项目决策研究

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水电能源科学 2010年第9期28卷 145-147页

作者：曹芳华北电力大学能源与电力研究咨询中心北京102206

为提高输变电工程项目决策效率,根据输变电工程项目决策需求建立了输变电工程项目的综合评判因素体系,并根据其层级特点,采用两级模糊综合评判模型对输变电工程项目进行评估。通过实例验证了该模型的合理性和可操作性,对实际输变电工程... 详细信息

为提高输变电工程项目决策效率,根据输变电工程项目决策需求建立了输变电工程项目的综合评判因素体系,并根据其层级特点,采用两级模糊综合评判模型对输变电工程项目进行评估。通过实例验证了该模型的合理性和可操作性,对实际输变电工程项目决策具有一定参考价值。

关键词：两级模糊综合评判输变电工程项目决策研究 Fuzzy Comprehensive Evaluation Based Decision Making 项目决策模糊综合评判模型因素体系实例验证可操作性决策效率参考价值合理性需求特点评估

Load Frequency Control:Problems and Solutions

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Load Frequency Control:Problems and Solutions

第三十届中国控制会议

作者： TAN Wen school of Control & Computer engineering,north china electric power university,beijing 100206,P.R.china

＜正＞Frequency control is one of the most profitable auxiliary services for the power systems through maintaining short-term balance of energy and frequency of the power *** control is usually accomplished through generator governor response（primary frequency regulation） and Load Frequency Control（LFC）.The goal of LFC is to reestablish primary frequency regulation capacity,return the frequency to its nominal value and minimize unscheduled tie-line power flows between neighboring control *** paper first formulates the LFC problem for single-area power systems as a disturbance rejection problem and discuss the effect of system parameters and the generation rate constraints（GRC） on the control *** decentralized LFC for multi-area power systems is formulated and a result on checking the stability of the closed-loop system considering the inherent structure of the multi-area power systems is ***,LFCs with communication delays and in deregulated market are formulated and a unified LFC-PID tuning method is *** is shown that the load frequency control problem is a typical disturbance rejection problem with rate limit,parameter variations,structural uncertainties and communication *** control techniques are expected to be applied to improve the control performance.

关键词： Load Frequency Control power Systems Robustness Disturbance Rejection Generation Rate Constraints