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力-电环境促进骨形成的机制──骨局部因子 被引量:3
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作者 郑磊 《生物医学工程学杂志》 CAS CSCD 北大核心 2000年第2期218-222,共5页
应力应变环境及电、磁场刺激骨形成的机理尚不十分清楚,最近研究发现力-电环境可通过诱导骨生成细胞产生各种骨局部因子,如前列腺素E2(PGE2)、胰岛素样生长因子Ⅱ(IGF-Ⅱ)、骨形态发生蛋白(BMP)和β转化生长因子(TGF-β)等参... 应力应变环境及电、磁场刺激骨形成的机理尚不十分清楚,最近研究发现力-电环境可通过诱导骨生成细胞产生各种骨局部因子,如前列腺素E2(PGE2)、胰岛素样生长因子Ⅱ(IGF-Ⅱ)、骨形态发生蛋白(BMP)和β转化生长因子(TGF-β)等参与骨形成及改建。本文介绍了几种重要的骨局部因子以及力-电环境诱导骨生成细胞产生骨局部因子的研究进展。 展开更多
关键词 力-电环境 骨局部因子 骨形成
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地球环境电、磁力与成矿系统相关关系浅析 被引量:1
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作者 孙忠实 邓军 张世红 《地学前缘》 EI CAS CSCD 2004年第1期195-199,共5页
文中根据电、磁力与多种元素分异和富集之间的内在联系 ,探求成矿系统的形成作用。初步认识如下 :(1 )地球环境电力可控制金属元素正、负离子朝向正、负电极各自作相向漂移运动 ,使核、幔金属元素呈不均匀分布 ,为成矿系统金属元素预富... 文中根据电、磁力与多种元素分异和富集之间的内在联系 ,探求成矿系统的形成作用。初步认识如下 :(1 )地球环境电力可控制金属元素正、负离子朝向正、负电极各自作相向漂移运动 ,使核、幔金属元素呈不均匀分布 ,为成矿系统金属元素预富集—富集提供了运移的动力和空间 ;(2 )地球环境磁斥力和磁引力与成矿系统中金、有色多金属和黑色金属具明显的对应关系 ,即各自集中分布或相互垂直分布 ;(3)地球环境电、磁力交替变化有利于成矿系统矿质巨量富集 ;(4 )通过流动电位可求出流体推动压力与电力间的量化关系 ,加大流体脉动贯入与成矿系统中多种元素本身性质间的联系 ;(5 )根据电、磁力与流体参数间高灵敏度的对应关系 ,能深入研究成矿系统形成时各个温度段、压力段、多期多元素多源流体随机变化的过程及形成机理 ;(6 )地球环境电、磁力与板块构造和岩石可构成地质背景组合 ,这些将有助于大陆成矿作用动力学更深入性的研究。 展开更多
关键词 环境 环境 环境-磁交替 成矿系统
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Research on Electro-Magnetic Environment of UHV Transmission Lines
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作者 Wu Guifang Lu Jiayu +1 位作者 Shao Fangyin Ye Qing 《Electricity》 2005年第3期42-46,共5页
Employing even higher voltage level to promote power transmission economy is an important subject in the program of power transmission from west to east. The influence of electro-magnetic environment of transmission p... Employing even higher voltage level to promote power transmission economy is an important subject in the program of power transmission from west to east. The influence of electro-magnetic environment of transmission project being closely related with human health and construction cost has to be seriously considered before advancing transmission voltage. This paper analyzes and discusses overseas and domestic research achievements on radio interference, audible noise, power frequency electric field, power frequency magnetic fields, DC resultant field intensity and ion stream involved in power transmission at ultra-high-voltage (UHV)AC and ± 800 kV DC or even higher voltage levels. Suggestions on limiting electro-magnetic effects and their ceiling value as well as measures to improve electro-magnetic environment are put forward. 展开更多
关键词 electro-magnetic environment power transmission DC UHV
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Construction of Three-dimensional power security Defense System Based on T-S Model Fuzzy Neural Network
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作者 Zeyu SUN 《International Journal of Technology Management》 2015年第5期105-108,共4页
With the development of information networks, the problem of power security has increasingly caused many attention of people, but the simple power security defense system has been difficult to meet the current complex... With the development of information networks, the problem of power security has increasingly caused many attention of people, but the simple power security defense system has been difficult to meet the current complex network environment. Aiming at this situation, by using the method of T-S fuzzy neural network model to analyze the characteristics of the data transmission in network, it has obtained corresponding threat information. By processing these threat information, it completes the construction of three-dimensional power security defense system. The paper carries on the corresponding data training methods by using T-shirt model fuzzy neural network, which has certain reference significance for the data analysis of other similar fields. At the same time, the study of building on the three-dimensional power security defense system aims to provide a theoretical reference for solving the security defense of the current complex network environment. 展开更多
关键词 Information network power security Neural network Network environment Data FEATURE Threat information
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Empirical study on evaluation of regional agri-food logistics capability in e-commerce environment based on factor analysis A case study of Hebei province
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作者 YANG Lei ZHANG Yi-zhen 《Chinese Business Review》 2010年第12期38-43,共6页
With SPSS16.0 software, this paper chooses the statistical data of 11 cities in Hebei province to empirically study the agri-food logistics capability based on the method of factor analysis, and finally obtains the ra... With SPSS16.0 software, this paper chooses the statistical data of 11 cities in Hebei province to empirically study the agri-food logistics capability based on the method of factor analysis, and finally obtains the ranking of the 11 cities. It shows that, factor-cluster analysis is an effective method to analyze the logistics capability of agri-food. It can simplify the original complicated problem and lead to an objective, reliable and convincing conclusion. 展开更多
关键词 factor analysis E-COMMERCE agri-food logistics regional logistics capability
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Application of Fuzzy-AHP method in the evaluation of logistics capability in e-commerce environment
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作者 YANG Lei ZHANG Yi-zhen 《Chinese Business Review》 2010年第10期51-56,共6页
In order to solve the complex problem of evaluation of logistics capability in e-commerce environment, an index system model of logistics capability is established based on the method of Fuzzy-AHP in this paper. The r... In order to solve the complex problem of evaluation of logistics capability in e-commerce environment, an index system model of logistics capability is established based on the method of Fuzzy-AHP in this paper. The results show that the method of Fuzzy-AHP is a powerful and flexible multi-criteria decision-making tool for dealing with complex problems where both qualitative and quantitative aspects need to be considered, and the human preference model is uncertain and decision-makers are reluctant or unable to assign exact numerical values to the comparison judgments. The evaluation model of logistics capability based on method of Fuzzy-AHP can help to make an effective decision in the evaluation of logistics capability. By this way we can effectively deal with the uncertainty and vagueness in the evaluation process of logistics capability. Logistics companies can diagnose their own weaknesses in the area of logistics and enhance their competitiveness. 展开更多
关键词 FUZZY-AHP E-COMMERCE logistics capability
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Research Reports on the 12^(th) Five-Year Plan for Electric Power Industry Power Grids
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作者 China Electricity Council Zhang Weidong Su Hangtian Liu Jing 《Electricity》 2011年第3期1-6,共6页
China Electricity Council organized competent authorities across the industry of electric power to work out the "Research Reports on the 12^th Five-Year Plan for Electric" Power lndustry "" in nearly one year, whi... China Electricity Council organized competent authorities across the industry of electric power to work out the "Research Reports on the 12^th Five-Year Plan for Electric" Power lndustry "" in nearly one year, which provides a reference/or governmental departments to formulate the 12^th Five-Year Plan on energy and electric power industry. The magazine should publish the serial reports inchliding power sources, power grids, equipment manufacture, energy and environment, and power economics. This paper presents the part of " power grids, " in which the strategies of developing power grids are put forward. 展开更多
关键词 power grids PLANNING electric power industry
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Discussion on the Construction of low-carbon electricity technology innovation system
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作者 Ge Pan 《International Journal of Technology Management》 2014年第1期29-31,共3页
With the issue of climate change increasingly restricting the sustainable development of society, people must realize that we must control atmospheric concentrations of greenhouse gases at a certain level. However, th... With the issue of climate change increasingly restricting the sustainable development of society, people must realize that we must control atmospheric concentrations of greenhouse gases at a certain level. However, the traditional model of economic development will lead to human demand for energy continuing to grow, followed by a growth in emissions of carbon dioxide. Obviously we must ensure that there is rapid economic development, but also to protect the human living environment, which is a very sharp contradiction. A good solution to this conflict is to take a new model of development --- a low-carbon economy. The so-called low-carbon economy refers to the reduction of greenhouse gas emissions, the application of new technologies, new materials and new practices, etc., through improvements, optimization or innovative production and business activities, to achieve the maximum degree of reduction of greenhouse gas emissions, and the formation of a new economic development model, the goal is to mitigate climate change and promote sustainable human development. On how to develop a low-carbon economy, domestic and foreign scholars have been studied from many angles, one of which is a consensus to reduce greenhouse gas emissions through the development and use of low-carbon technologies. 展开更多
关键词 CARBON ELECTRICITY technological innovation
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Metals Recovery from Fine Printed Circuit Boards Using Falcon SB Concentrator 被引量:2
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作者 WEN Xue-feng ZHAO Yue-min +3 位作者 PAN Yan-jun HE Ya-qun SONG Shu-lei WANG Zhuo-ya 《Journal of China University of Mining and Technology》 EI 2005年第4期322-328,共7页
Physical methods show great potential and advantages on comprehensive reutilization of waste printed circuit boards (PCBs) because of lower investment and operation cost, higher efficiency and environment friendliness... Physical methods show great potential and advantages on comprehensive reutilization of waste printed circuit boards (PCBs) because of lower investment and operation cost, higher efficiency and environment friendliness. However, metals contained in fine fraction of PCBs cannot be recovered effectively by conventional equipments such as high tension electrostatic separator or shaking table. In the paper, this conundrum was resolved successfully with the enhanced Falcon SB concentrator. The separation mechanism of Falcon SB concentrator was analyzed and main factors affecting separation efficiency such as magnitude of rotation frequency of bowl, water counter pressure and slurry concentration of feed were studied and interaction of factors above also were investigated using Design-Expert software. Experiment results show that complete liberation degree and great difference of density between metals and nonmetals are suitable to recover metals from -74 μm PCBs using enhanced Falcon SB concentrator and 80.77 % integration efficiency can be achieved when slurry concentration of feed is 40 g/L with the water counter pressure of 0.01 MPa and rotation frequency of 50 Hz. 展开更多
关键词 Falcon concentrator centrifugal separation waste printed circuit boards integration efficiency
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OVERVIEW OF ENVIRONMENTAL ASSESSMENT FOR CHINANUCLEAR POWER INDUSTRY AND COAL-FIRED POWER INDUSTRY
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作者 张少东 潘自强 张永兴 《Nuclear Science and Techniques》 SCIE CAS CSCD 1994年第4期225-229,共5页
A quantitative environmental assessment method and the corresponding computer code are introduced in this paper. By the consideration of all fuel cycle steps,it gives that the public health risk of China nuclear power... A quantitative environmental assessment method and the corresponding computer code are introduced in this paper. By the consideration of all fuel cycle steps,it gives that the public health risk of China nuclear power industry is 5.2 × 10-1 man /(GW.a), the occupational health risk is 2.5 man /(GW.a), and the total health risk is 3.0 man /(GW.a). After the health risk calculation for coal mining, transport, burning up and ash disposal, it gives that the public health risk of China coal-fired power industry is 3.6mall/(GW-a), the occupational health risk is 50man /(GW.a), and the total is 54man /(GW.d). Accordingly, the conclusion that China nuclear power industry is an industry with high safety and cleanness is derived at the end. 展开更多
关键词 Environment assessment Energy and environment Nuclear power plant Coal-fired power plant Health risk
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Microscopic analysis of saturated soft clay in Pearl River Delta 被引量:3
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作者 周晖 房营光 +1 位作者 谷任国 曾铖 《Journal of Central South University》 SCIE EI CAS 2011年第2期504-510,共7页
A series of researches were carried out for the soil samples in the Pearl River Delta under the action of consolidation loads,such as the quantitative analyses of the pore scale,shape and size distributions of micro-s... A series of researches were carried out for the soil samples in the Pearl River Delta under the action of consolidation loads,such as the quantitative analyses of the pore scale,shape and size distributions of micro-structure units,with an environmental scanning electron microscope (ESEM),a mercury intrusion analyzer and a mineral diffractometer. The experimental results show that the consolidation pressures remarkably change the pore sizes and distribution characteristics of the silt,thus changing its compressibility and permeability. This can be proved by the fact that,in the earlier stage with a consolidation pressure of p<200 kPa,the pore sizes are greater and the compressibility and permeability coefficients are larger. However,they rapidly decrease with the increase in consolidation pressure. And in the later stage with a consolidation pressure of p>200 kPa,the pore sizes are smaller and the compressibility and permeability coefficients are less. Therefore,the empirical formulas of compression coefficient and permeability coefficient vs consolidation load and average pore diameter are deduced. 展开更多
关键词 saturated soft soil Pearl River Delta (PRD) MICRO-STRUCTURE microscopic analysis pore distribution engineeringproperties
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Dynamics of Environmental Ionizing Radiation between May to September 2016 in the Region of S^o Jos~ dos Campos, SP, Brazil
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作者 Inacio M. Martin Marcelo P. Gomes +5 位作者 Mauro A. Alves Alessandro de Abreu Franklin A. Silva Rodrigo R. F.Carvalho Joao P. Correa Bogos N. Sismanoglu 《Journal of Environmental Science and Engineering(B)》 2016年第9期451-456,共6页
Measurements of gamma radiation (200 keV to 10 MeV) were performed between May 25 to September 30 2016 at ITA (Technological Institute of Aeronautics) in Sao Jose dos Campos, SP, Brazil. Detector and associated el... Measurements of gamma radiation (200 keV to 10 MeV) were performed between May 25 to September 30 2016 at ITA (Technological Institute of Aeronautics) in Sao Jose dos Campos, SP, Brazil. Detector and associated electronics were previously calibrated in the laboratory of ITA using radioactive sources Cs-137, Po-210 and Sr-90. These sources provide gamma-ray energies in 0.662 keV alpha particles of 5.4 MeV and 0.90 keV electrons, respectively. Detector is a scintillator Sodium Iodide activated with Thallium [NaI(Tl)] associated to a photomultiplier and electronic devices which gather, store, distribute and structure data so users can analyze them. During the period of May-September, the experimental set was installed in an open room on a tower 25 meters above the ground. Measurements indicated variations of ionizing radiation in function of dry weather, rain, cold fronts passes and presence of fog in the area; the sample time interval was minute by minute. This study discusses the analysis and the dynamics of how to measure meteorological parameters using an ionizing radiation system. 展开更多
关键词 Ionizing radiation environmental study gamma radiation measurements.
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Environmental Issues and Management for Hydropower Peaking Operations
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作者 Helen Locher 《Small Hydro Power News》 2005年第81期15-19,共5页
Many hydropower plants are operated as peak generators or frequency controllers, because they can change their output quickly to follow the fluctuating power demand. When meeting peak load requirements, a power statio... Many hydropower plants are operated as peak generators or frequency controllers, because they can change their output quickly to follow the fluctuating power demand. When meeting peak load requirements, a power station is turned on at a particular time during the day, generates power at a constant load for a certain number of hours, and is then turned off or set to a different load for another time period, resulting in a high variability inflow discharges. Where reservoir hydro schemes are operated primarily to provide peak load services, there are particular environmental risks that should be considered in any environmental impact assessment. At a minimum these should focus on water quality, fluvial geomorphology, riparian vegetation, macro-invertebrate and fish communities underpinned by a sound hydrological analysis. Frequent temperature changes may occur downstream of a peaking power station; increased seepage-induced erosion of riverbanks due to frequent water level drawdowns; and impacts to macro-invertebrate and fish communities due to rapid and frequent in channel habitat conditions. With a sound understanding of the potential environmental issues, there are strategies that can be employed at the siting and design stage to minimize or mitigate these risks, including but not limited to minimum environmental flows, ramping rules, utilization of a re-regulation storage and localized treatment works. 展开更多
关键词 HYDROPOWER ENVIRONMENTAL peaking HYDROPEAKING MITIGATION
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Environmental Challenges to Thermal Power Construction
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作者 Zhu Fahua Chu Xue(Translated) 《Electricity》 2006年第1期47-51,共5页
Environmental protection challenges thermal power construction from respects of the reform of investment system, main industrial policies and plant site selection in China. Pollution control of thermal power plants is... Environmental protection challenges thermal power construction from respects of the reform of investment system, main industrial policies and plant site selection in China. Pollution control of thermal power plants is analyzed from the angles of increasingly stringent laws, regulations and standards as well as approval procedures of thermal power projects. The paper points out emphatically that the plant site selection of a thermal power project must satisfy various requirements of rules and regulations, development programme and environmental ftmctions, etc. Different criteria of dust, SO2, NOx and other pollutants control are enumerated speeially. 展开更多
关键词 thermal power environmental protection industrial policy overall control
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Pushing Forward Industrialization of Thermal Power Desulfuration
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作者 Pan Li Wang Zhixuan Jin Wen 《Electricity》 2005年第3期52-54,共3页
This paper introduces present state of industrialization development in flue gas desulfuration, including technological selection, state of design and contracting capability, localization of equipment, etc. in China. ... This paper introduces present state of industrialization development in flue gas desulfuration, including technological selection, state of design and contracting capability, localization of equipment, etc. in China. It points out main problems currently existed and presents proposals on promotion of desulfuration technology with selfowned intellectual property right, perfection of demonstrative projects and pushing forward localization of desulfuration equipment. 展开更多
关键词 flue gas desulfuration INDUSTRIALIZATION thermal power plant
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Evaluation of Greenhouse Gas Emissions from and the Economic Efficiency of the "Hita City Biomass Recycle Center" 被引量:1
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作者 Takanobu Hamasaka 《Journal of Environmental Science and Engineering(B)》 2015年第8期426-433,共8页
Many biomass recycling facilities have been established in Japan, but its environmental efficiencies have been studied little. MIC has stated that these facilities do not work as well as expected. The environmental an... Many biomass recycling facilities have been established in Japan, but its environmental efficiencies have been studied little. MIC has stated that these facilities do not work as well as expected. The environmental and economic efficiencies ofa biomass recycling center (representative of other recycling facilities) in Hita city are assessed here. The center was built to decrease the amount of waste needing to be disposed of, and is unusual in that it generates electricity using the methane produced. Electricity produced from biomass sells at a higher price than electricity sold by electricity companies in Japan, and this strongly affects the recycling center operation. The environmental efficiency of the recycling center was assessed using a lifecycle assessment method, and the economic efficiency was assessed from the amounts of greenhouse gases emitted and the running costs. As the result, it was clear that the recycling center emits about 20% of the greenhouse gases that were previously emitted. Treating biomass at the recycling center costs 1,356 yen per ton of biomass throughout the year. In conclusion, the recycling center decreases the environmental footprint of Hita city. The cost of decreasing greenhouse gas emissions is about 1,400 yen per ton of biomass. 展开更多
关键词 Life cycle assessment greenhouse gas methane fermentation apparatus.
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Green Demonstrated Analysis on Structure of Our Electric Power Resource
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作者 杨俊保 余静 陈金晶 《Journal of Donghua University(English Edition)》 EI CAS 2004年第5期150-154,共5页
According to green view and history data, the demonstrated method is applied to analyze the green rationality on the present structure of thermal, hydraulic and nuclear electric power resource; the green trend of larg... According to green view and history data, the demonstrated method is applied to analyze the green rationality on the present structure of thermal, hydraulic and nuclear electric power resource; the green trend of large-scale on thermal power generating unit in our history; the distribution of between water and coal resource with the space structure of electric power installed capacity, and recommending the premise, dominance and direction of building our green electric power structure in the future. 展开更多
关键词 STRUCTURE Electric Power Resource Green Demonstrated Analysis
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Voluntary Carbon Market in Turkey
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作者 Fehiman Ciner Aydemir Akyurek 《Journal of Energy and Power Engineering》 2014年第11期1908-1912,共5页
Nowadays, global warming is a major environmental concern. Climate change is dominating the environmental agendas, especially in developed countries at first, but by now, around the world. Several initiatives have bee... Nowadays, global warming is a major environmental concern. Climate change is dominating the environmental agendas, especially in developed countries at first, but by now, around the world. Several initiatives have been undertaken to reduce the effect of increasing atmospheric GHGs (greenhouse gasses) concentrations. Emerging carbon emissions trade under the Kyoto Protocol serves to market the carbon quotas among the countries, thus, it helps to increase their level of GNP (gross national product). Emissions trade is being performed in the voluntary and compliant markets. Increasing interest in emission trade emerged carbon and energy exchanges markets in the world. Turkey is located in the voluntary markets, and organizations buying carbon offset credits in order to achieve their voluntary emission reduction goals. GS (gold standard) and VCS (verified carbon standard) are mainly being used to finance renewable energy projects in Turkey. In the GS, there are 209 projects which are currently in the approval process or in the application, such as wind energy, hydroelectric power plant and biogas energy production. In addition to these, in the VCS, there are 61 projects which are mainly energy industries, in the approval process or in the application. Most environmental issues require long-term plans which include international cooperation, especially climate change. The Kyoto Protocol marks the beginning of a new era to combat global climate change. Voluntary markets are very popular and forty percent of the total global GS projects and around nine percent of VCS projects are implemented in Turkey. These projects are initial steps for future implementations of compliant markets in Turkey. 展开更多
关键词 Kyoto protocol carbon markets voluntary carbon trade greenhouse gas Turkey.
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Pressure Tolerant Power Electronics: IGBT Gate Driver for Operation in High Pressure Hydrostatic Environment
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作者 Riccardo Pittini Magnar Hernes Kjell Ljokelsoy 《Journal of Energy and Power Engineering》 2012年第9期1500-1508,共9页
Abstract: This paper presents results from an on-going research project on pressure tolerant power electronics at SINTEF Energy Research, Norway. The driving force for this research is to enable power electronic comp... Abstract: This paper presents results from an on-going research project on pressure tolerant power electronics at SINTEF Energy Research, Norway. The driving force for this research is to enable power electronic components to operate in pressurized dielectric environment. The intended application is the converters for operation down to 3,000 meters ocean depth, primarily for subsea oil and gas processing. The paper focuses on the needed modifications to a general purpose gate driver for IGBT (insulated gate bipolar transistors) that will give pressure tolerance. Adaptations and modifications of the individual driver components are presented.The results from preliminary testing are promising, which shows that the considered adaptations give feasible solutions. 展开更多
关键词 Pressure tolerant power electronics IGBT gate driver voltage source converter capacitors power semiconductors.
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Preparation and Characterization of a Novel Polyamide Charged Mosaic Membrane 被引量:2
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作者 张景亚 张延武 +2 位作者 张浩勤 党敬川 刘金盾 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第4期569-576,共8页
A novel composite charged mosaic membrane(CCMM) was prepared via interfacial polymerization(IP) of polyamine[poly(epichlorohydrin amine) ]and trimesoyl chloride(TMC) on the polyethersulfone(PES) support. Fourier trans... A novel composite charged mosaic membrane(CCMM) was prepared via interfacial polymerization(IP) of polyamine[poly(epichlorohydrin amine) ]and trimesoyl chloride(TMC) on the polyethersulfone(PES) support. Fourier transform infrared spectroscopy(FT-IR) ,environmental scanning electron microscopy(ESEM) ,atomic force microscopy(AFM) and water contact angle analysis were applied to characterize the resulted CCMM.The FT-IR spectrum indicates that TMC reacts sufficiently with polyamine.ESEM and AFM pictures show that the IP process produces a dense selective layer on the support membrane.The water contact angle of the CCMM is smaller than that of the substrate membrane because of the cross-linked hydrophilic polyamine network.Several factors affecting the IP reaction and the performance of the CCMM,such as monomer concentration,reaction time,pH value of aqueous phase solution and post-treatment,were studied.The pure water flux of the optimized CCMM is 14.73 L·m -2 ·h -1 ·MPa -1 at the operating pressure of 0.4 MPa.The values of separation factorαfor NaCl/PEG1000/water and MgCl2/PEG1000/water are 11.89 and 9.96,respectively.These results demonstrate that CCMM is promising for the separation of low-molecular-weight organics from their salt aqueous solutions. 展开更多
关键词 charged mosaic membranes interfacial polymerization POLYAMINE FLUX RETENTION
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