期刊文献+
共找到286,212篇文章
< 1 2 250 >
每页显示 20 50 100
Dual‑Donor‑Induced Crystallinity Modulation Enables 19.23% Efficiency Organic Solar Cells
1
作者 Anhai Liang Yuqing Sun +9 位作者 Sein Chung Jiyeong Shin Kangbo Sun Chaofeng Zhu Jingjing Zhao Zhenmin Zhao Yufei Zhong Guangye Zhang Kilwon Cho Zhipeng Kan 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期376-388,共13页
Trap-assisted charge recombination is one of the primary limitationsof restricting the performance of organic solar cells. However, effectivelyreducing the presence of traps in the photoactive layer remains challengin... Trap-assisted charge recombination is one of the primary limitationsof restricting the performance of organic solar cells. However, effectivelyreducing the presence of traps in the photoactive layer remains challenging.Herein, wide bandgap polymer donor PTzBI-dF is demonstrated as an effectivemodulator for enhancing the crystallinity of the bulk heterojunction active layerscomposed of D18 derivatives blended with Y6, leading to dense and orderedmolecular packings, and thus, improves photoluminescence quenching properties.As a result, the photovoltaic devices exhibit reduced trap-assisted charge recombinationlosses, achieving an optimized power conversion efficiency of over 19%.Besides the efficiency enhancement, the devices comprised of PTzBI-dF as athird component simultaneously attain decreased current leakage, improved chargecarrier mobilities, and suppressed bimolecular charge recombination, leading toreduced energy losses. The advanced crystalline structures induced by PTzBI-dFand its characteristics, such as well-aligned energy level, and complementaryabsorption spectra, are ascribed to the promising performance improvements.Our findings suggest that donor phase engineering is a feasible approach to tuning the molecular packings in the active layer, providingguidelines for designing effective morphology modulators for high-performance organic solar cells. 展开更多
关键词 Trap-assisted charge recombination PHOTOLUMINESCENCE MISCIBILITY current leakage Power conversion efficiency
下载PDF
Current efficiency of recycling aluminum from aluminum scraps by electrolysis 被引量:3
2
作者 徐君莉 张净 +3 位作者 石忠宁 高炳亮 王兆文 胡宪伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期250-256,共7页
Extracting aluminum from aluminum alloys in AlCl3-NaCl molten salts was investigated. Al coating was deposited on the copper cathode by the method of direct current deposition using aluminum alloys as anode. The purit... Extracting aluminum from aluminum alloys in AlCl3-NaCl molten salts was investigated. Al coating was deposited on the copper cathode by the method of direct current deposition using aluminum alloys as anode. The purity of the deposited aluminum is about 99.7% with the energy consumption of 3-9 kW&#183;h per kg Al, and the current efficiency is 44%-64% when the deposition process is carried out under 100 mA/cm2 for 4 h at 170 &#176;C. The effects of experimental parameters, such as molar ratio of AlCl3 to NaCl, cathodic current density and electrolysis time, on the current efficiency were studied. The molar ratio of AlCl3 to NaCl has little effect on the current efficiency, and the increase of deposition temperature is beneficial to the increase of current efficiency. However, the increase of current density or electrolysis time results in the decrease of current efficiency. The decrease of current efficiency is mainly related to the formation of dendritic or powder deposit of aluminum which is easy to fall into the electrolyte. 展开更多
关键词 aluminum recycling aluminum alloy current efficiency ELECTROLYSIS chlorides molten salts
下载PDF
Preparation of electrolytic copper powders with high current efficiency enhanced by super gravity field and its mechanism 被引量:8
3
作者 王明涌 王志 郭占成 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1154-1160,共7页
Super gravity field was employed to enhance electrolytic reaction for the preparation of copper powders.The morphology, microstructure and size of copper powders were characterized by scanning electron microscopy,X-ra... Super gravity field was employed to enhance electrolytic reaction for the preparation of copper powders.The morphology, microstructure and size of copper powders were characterized by scanning electron microscopy,X-ray diffractometry and laser particle analysis.The results indicated that current efficiencies of electrolytic copper powders under super gravity field increased by more than 20% compared with that under normal gravity condition.Cell voltage under super gravity field was also much lower.The size of copper powders decreased with the increase of gravity coefficient(G).The increase of current efficiency can be contributed to the disturbance of electrode/electrolyte interface and enhanced mass transfer of Cu2+ in super gravity field.Meanwhile,the huge gravity acceleration would promote the detachment of copper powders from electrode surface during electrolytic process,which can prevent the growth of copper powders. 展开更多
关键词 super gravity field current efficiency copper powders ELECTROLYSIS
下载PDF
Current Efficiency, Corrosion and Structural Changes in SnO2-Sb2O3-CuO Inert Anodes for Aluminium Electrolysis 被引量:2
4
作者 Ana-Maria Popescu Virgil Constantin 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第3期368-372,共5页
A systematic study was conducted on current efficiency (CE), corrosion and structural changes in SnO2-based inert anodes (made of 96wt%SnO2+2wt%Sb2O3+2wt%CuO) on a laboratory Hall-Heroult aluminium cell. The inf... A systematic study was conducted on current efficiency (CE), corrosion and structural changes in SnO2-based inert anodes (made of 96wt%SnO2+2wt%Sb2O3+2wt%CuO) on a laboratory Hall-Heroult aluminium cell. The influence of operating parameters and electrolyte composition on the CE and corrosion process were evaluated. The CE was found to be more than 90% and catastrophic corrosion took place at low percent of Al2O3, high percent of LiF, low cryolite ratio and high current densities. From all the structural changes that took place in the SnO2-based inert anodes, we assumed that the most important contribution was due to the migration of CuO towards the outer limits of the constituent grains of SnO2 based ceramic. The complex process occurred during the formation of various phases and their sintering ability both directly depended on Cu/Sb molar ratio. 展开更多
关键词 Inert anode Aluminium electrowinning current efficiency
下载PDF
MATHEMATICAL MODEL FOR CONTINUOUS DETECTION OF CURRENT EFFICIENCY IN ALUMINUM PRODUCTION 被引量:5
5
作者 Zeng Shuiping Institute of Fuzzy Control, North China University of Technology, Beijing 100041, P. R. China Liu Yexiang and Mei Chi Department of Nonferrous Metallurgy, Central South University of Technology, Changsha 410083, P. R. China 《中国有色金属学会会刊:英文版》 CSCD 1998年第4期152-156,共5页
INTRODUCTIONThemathematicalmodelsforcalculationofcurenteficiencyinaluminareductionhavebenreportedbymanyinves... INTRODUCTIONThemathematicalmodelsforcalculationofcurenteficiencyinaluminareductionhavebenreportedbymanyinvestigators,mostofwh... 展开更多
关键词 current efficiency MATHEMATICAL MODEL aluminium ELECTROLYSIS
下载PDF
Current efficiency in electro-winning of lanthanum and cerium metals from molten chloride electrolytes 被引量:1
6
作者 Deepak Kumar Sahoo Harvinderpal Singh Nagaiyar Krishnamurthy 《Rare Metals》 SCIE EI CAS CSCD 2013年第3期305-311,共7页
The objective of this study is to prepare lan- thanum and cerium metals by fused salt electrolysis of their anhydrous chloride in molten media such as LiCl-KCl, NaCl-KCl, KCl, NaCl, and LiCl and to characterize the me... The objective of this study is to prepare lan- thanum and cerium metals by fused salt electrolysis of their anhydrous chloride in molten media such as LiCl-KCl, NaCl-KCl, KCl, NaCl, and LiCl and to characterize the metal deposit by X-ray diffraction, energy dispersive X-ray fluorescence, and inductive coupled plasma-atomic emis- sion spectroscopy. Deposit metal of purity more than 99 % was obtained in each of the experiments. The entire process starting from preparation of anhydrous lanthanum/cerium chloride to electrolysis yielding of metal deposits has been described. The effect of process parameters such as tem- perature, electrolyte composition, and current density on the current efficiency was studied. All these parameters were varied to get the highest current efficiency and metal yield. The major non-rare earth impurities with the deposit are found to be Fe, Cr, and Ni along with - 1× 10^-3 of total gaseous impurities. 展开更多
关键词 Fused salt electrolysis current density current efficiency Rare earths
下载PDF
Current efficiency improvement of Zn-Fe alloy electrodeposition by hydrogen inhibitor 被引量:1
7
作者 王云燕 肖海娟 柴立元 《Journal of Central South University of Technology》 EI 2008年第6期814-818,共5页
In order to inhibit hydrogen evolution and enhance current efficiency of Zn-Fe alloy electrodeposition from alkaline zincate solution, hydrogen inhibitors composed of the sulfur group elements were optimized on the ba... In order to inhibit hydrogen evolution and enhance current efficiency of Zn-Fe alloy electrodeposition from alkaline zincate solution, hydrogen inhibitors composed of the sulfur group elements were optimized on the basis of atom structures analysis. The effects of hydrogen inhibitor on the current efficiency of Zn-Fe alloy electroplating and their electrochemical behaviors were studied. The results indicate that hydrogen inhibitor can increase the current efficiency of Zn-Fe alloy electroplating evidently, from 63.28% without hydrogen inhibitor up to 83.54% with a hydrogen inhibitor at a volume fraction of 2.0%, while it has a minor influence on that of pure Zn plating, which maintains at 80%. The optimum volume fraction of hydrogen inhibitor is 2.0%. 展开更多
关键词 Zn-Fe alloy hydrogen inhibitor current efficiency electrochemical behavior ELECTRODEPOSITION
下载PDF
Optimization of Lower Hybrid Current Drive Efficiency for EAST Plasma with Non-Circular Cross Section and Finite Aspect-Ratio 被引量:1
8
作者 侍行剑 胡业民 高喆 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第3期215-221,共7页
The two-dimensional equilibrium with flexible boundaries is solved via using a MAT- LAB Equilibrium Code (MEC), which has applied the finite element method to handle the change- able plasma shape and employed the tr... The two-dimensional equilibrium with flexible boundaries is solved via using a MAT- LAB Equilibrium Code (MEC), which has applied the finite element method to handle the change- able plasma shape and employed the trust-region dogleg method to solve the nonlinear partial dif- ferential equation. The corresponding driven current profile is also calculated by coupling with the lower-hybrid simulation code (LSC). The results are applied to optimize the lower hybrid current drive (LHCD) efficiency for the Experimental Advanced Superconductor Tokamak (EAST) and suggested that both elongation and triangularity have a notable effect on the efficiency because of the competition between the increase in the resonant area and in the Shafranov shift. Moreover, large aspect-ratio has a negative effect on the efficiency. These effects are studied numerically, which might be considered carefully for both good plasma confinement and high LHCD efficiency. 展开更多
关键词 efficiency LHCD ELONGATION triangularity ASPECT-RATIO
下载PDF
The current status of nitrogen fertiliser use efficiency and future research directions for the Australian cotton industry 被引量:7
9
作者 MACDONALD Ben C.T. LATIMER James O. +2 位作者 SCHWENKE Graeme D. NACHIMUTHU Gunasekhar BAIRD Jonathan C. 《Journal of Cotton Research》 2018年第3期41-50,共10页
Fifty years of sustained investment in research and development has left the Australian cotton industry well placed to manage nitrogen(N) fertiliser. The average production in the Australian cotton industry today is... Fifty years of sustained investment in research and development has left the Australian cotton industry well placed to manage nitrogen(N) fertiliser. The average production in the Australian cotton industry today is greater than two tonnes of lint per hectare due to improved plant genetics and crop management. However, this average yield is well below the yield that would be expected from the amount of N fertiliser used. It is clear from the recent studies that across all growing regions, conversion of fertiliser N into lint is not uniformly occurring at application rates greater than 200-240 kg·hm;of N. This indicates that factors other than N availability are limiting yield, and that the observed nitrogen fertiliser use efficiency(NFUE) values may be caused by subsoil constraints such as sodicity and compaction. There is a need to investigate the impact of subsoil constraints on yield and NFUE.Gains in NFUE will be made through improved N fertiliser application timing, better targeting the amount of fertiliser applied for the expected yield, and improved soil N management. There is also a need to improve the ability and confidence of growers to estimate the contribution of soil N mineralisation to the crop N budget. Many Australian studies including data that could theoretically be collated in a meta-analysis suggest relative NFUE values as a function of irrigation technique; however, with the extensive list of uncontrolled variables and few studies using non-furrow irrigation, this would be a poor substitute for a single field-based study directly measuring their efficacies. In irrigated cotton, a re-examination of optimal NFUE is due because of the availability of new varieties and the potential management and long-term soil resilience implications of the continued removal of mineralised soil N suggested by high NFUE values. NFUE critical limits still need to be derived for dryland systems. 展开更多
关键词 Nitrogen fertiliser Nitrogen use efficiency DRYLAND IRRIGATED
下载PDF
Analysis on Attenuation Efficiency of Lightning Current by Lightning Interceptor 被引量:1
10
作者 Hui YANG Zhongqiu SHI +4 位作者 Renhong GUO Yixian QIU Qiaobin WEI Ruping ZHOU Yu HUANG 《Meteorological and Environmental Research》 CAS 2023年第1期56-59,共4页
Lightning interception technology is one of the three core technical systems of regional lightning protection theory.Among them,the omni-directional multi-pulse lightning interceptor(hereinafter referred to as lightni... Lightning interception technology is one of the three core technical systems of regional lightning protection theory.Among them,the omni-directional multi-pulse lightning interceptor(hereinafter referred to as lightning interceptor,the same below)has the ability to attenuate lightning current≥40%and significantly reduce the intensity of the spatial electromagnetic field around the lightning point.In order to explore the attenuation mechanism and effect of lightning interceptor to lightning current,this paper analyzed a lightning stroke process at 16:00 on August 19,2022,and tried to explain the attenuation effect of lightning interceptor to lightning current with the physical parameters of lightning stroke. 展开更多
关键词 LIGHTNING INTERCEPTOR LIGHTNING current ATTENUATION efficiency Case ANALYSIS
下载PDF
Irrigation Methods and Scheduling in the Delta Region of Mississippi: Current Status and Strategies to Improve Irrigation Efficiency 被引量:2
11
作者 Hirut Kebede Daniel K. Fisher +1 位作者 Ruixiu Sui Krishna N. Reddy 《American Journal of Plant Sciences》 2014年第20期2917-2928,共12页
Even though annual rainfall is high in the Delta region of Mississippi, only 30% occurs during the months in which the major crops are produced, making irrigation often necessary to meet crop water needs and to avoid ... Even though annual rainfall is high in the Delta region of Mississippi, only 30% occurs during the months in which the major crops are produced, making irrigation often necessary to meet crop water needs and to avoid risk of yield and profitability loss. Approximately, 65% of the farmland in this region is irrigated. The shallow Mississippi River Valley Alluvial Aquifer is the major source of water for irrigation and for aquaculture in the predominant catfish industry. This groundwater is being heavily used as row-crop irrigation has increased tremendously. Water level in this aquifer has declined significantly over the past twenty five years, with overdraft of approximately 370 million cubic meters of water per year. Moreover, the common irrigation practices in the Delta re-gion of Mississippi do not use water efficiently, further depleting the ground water and making ir-rigation more expensive to producers due to increasing energy prices. Irrigation experts in the re-gion have tested and verified various methods and tools that increase irrigation efficiency. This article presents a review of the current status of the irrigation practices in the Delta region of Mis-sissippi, and the improved methods and tools that are available to increase irrigation efficiency and to reduce energy costs for producers in the region as well as to stop the overdraft of the declining aquifer, ensuring its sustainable use. 展开更多
关键词 The DELTA REGION of MISSISSIPPI IRRIGATION efficiency IRRIGATION SCHEDULING FURROW IRRIGATION Crop Water Use
下载PDF
Applied bias photon-to-current conversion efficiency of ZnO enhanced by hybridization with reduced graphene oxide 被引量:1
12
作者 Sharifah Bee Abdul Hamid Swe Jyan Teh +2 位作者 Chin Wei Lai Siglinda Perathoner Gabriele Centi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第2期302-308,共7页
The role of reduced graphene oxide(rGO) in the enhancement of photo-conversion efficiency of ZnO films for photoelectrochemical(PEC) water-splitting applications was analyzed. ZnO and rGO-hybridized ZnO(rGO/ZnO)... The role of reduced graphene oxide(rGO) in the enhancement of photo-conversion efficiency of ZnO films for photoelectrochemical(PEC) water-splitting applications was analyzed. ZnO and rGO-hybridized ZnO(rGO/ZnO) films were prepared via a two-step electrochemical deposition method followed by annealing at 300 °C under argon gas flow. The physical, optical and electrochemical properties of the films were characterized to identify the effect of rGO-hybridization on the applied bias photon-to-current efficiency(ABPE) of ZnO. Scanning electron microscopy and X-ray diffraction indicated the formation of verticallyaligned, wurtzite-phase ZnO nanorods. Diffuse-reflectance UV–visible spectroscopy indicated that rGO-hybridization was able to increase the light absorption range of the rGO/ZnO film. UPS analysis showed that hybridization with rGO increased the band gap of ZnO(3.56 eV) to 3.63 eV for rGO/ZnO sample,which may be attributed to the Burstein–Moss effect. Photoluminescence(PL) spectra disclosed that rGOhybridization suppressed electron-hole recombination due to crystal defects. Linear sweep voltammetry of the prepared thin films showed photocurrent density of 1.0 and 1.8 m A/cm;for ZnO and rGO/ZnO at+0.7 V, which corresponded to an ABPE of 0.55% and 0.95%, respectively. Thus, this report highlighted the multi-faceted role of rGO-hybridization in the enhancement of ZnO photo-conversion efficiency. 展开更多
关键词 Zinc oxide Photoelectrochemical water-splitting Reduced graphene oxide Photo-conversion efficiency
下载PDF
Efficiency droop suppression in GaN-based light-emitting diodes by chirped multiple quantum well structure at high current injection 被引量:1
13
作者 赵宇坤 李虞锋 +4 位作者 黄亚平 王宏 苏喜林 丁文 云峰 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期484-488,共5页
Gallium nitride (GaN) based light-emitting diodes (LEDs) with chirped multiple quantum well (MQW) structures have been investigated experimentally and numerically in this paper. Compared to conventional LEDs wit... Gallium nitride (GaN) based light-emitting diodes (LEDs) with chirped multiple quantum well (MQW) structures have been investigated experimentally and numerically in this paper. Compared to conventional LEDs with uniform quantum wells (QWs), LEDs with chirped MQW structures have better internal quantum efficiency (IQE) and carrier injection efficiency. The droop ratios of LEDs with chirped MQW structures show a remarkable improvement at 600 mA/mm2, reduced down from 28.6% (conventional uniform LEDs) to 23.7% (chirped MQWs-a) and 18.6% (chirped MQWs-b), respectively. Meanwhile, the peak IQE increases from 76.9% (uniform LEDs) to 83.7% (chirped MQWs-a) and 88.6% (chirped MQWs-b). The reservoir effect of chirped MQW structures is the significant reason as it could increase hole injection efficiency and radiative recombination. The leakage current and Auger recombination of chirped MQW structures can also be suppressed. Furthermore, the chirped MQWs-b structure with lower potential barriers can enhance the reservoir effect and obtain further improvement of the carrier injection efficiency and radiative recombination, as well as further suppressing efficiency droop. 展开更多
关键词 efficiency droop chirped multiple quantum well structure hole injection light-emitting diode
下载PDF
Current Efficiency of Low Temperature Aluminum Electrolysis Studied by Neural Network
14
作者 Huimin Lu Zuxian Qiu +2 位作者 Keming Fang Fuming Wang Yanruo Hong( Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China)( Department of Nonferrous Metallurgy, Northeastern University, Shenyang 110006, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第2期107-110,共4页
A prediction model for Current Efficiency (CE) of low temperature aluminum electrolysis (LTAE) with the low molar ratioelectfolyte of Na3AIF6-AIF3 - CaF2-MgF2-LiF -Al2O3 system was investigated based on artificial neu... A prediction model for Current Efficiency (CE) of low temperature aluminum electrolysis (LTAE) with the low molar ratioelectfolyte of Na3AIF6-AIF3 - CaF2-MgF2-LiF -Al2O3 system was investigated based on artificial neural network principles. The nonlinearmapping between CE of LATE and various electrolytic conditions was obtained from a number of experimental data and used to predictCE of LATE. The trsined neural networks possessed high precision and resulted in a good predicting effect. As a result, attificial neuralnetworks as a new cooperating and predicting technology provide a new approach to the further studies on low temperature aluminumelectrolysis. 展开更多
关键词 low temperatre aluminum electrolysis current efficiency neural network prediction model low molar ratio electrolyte
下载PDF
Mechanism of current efficiency improvement of Zn-Fe alloy electroplating by hydrogen inhibitor
15
作者 王云燕 柴立元 《Journal of Central South University of Technology》 EI 2007年第3期336-339,共4页
The effect of hydrogen inhibitor on partial current densities ofZn, Fe and differential capacitance of electrode/electrolyte interface, and adsorbing type of hydrogen inhibitor were studied by the methods of electroch... The effect of hydrogen inhibitor on partial current densities ofZn, Fe and differential capacitance of electrode/electrolyte interface, and adsorbing type of hydrogen inhibitor were studied by the methods of electrochemistry. The mechanism of current efficiency improvement were explained from the point of valence electron theory. The results indicate that the partial current density of Fe increases in addition of hydrogen inhibitor, which reaches the maximum of 0.14 A/dm^2 when current density is 0.2 A/din〈 Differential capacitance of electrode/electrolyte interface decreases obviously from 20.3μF/cm^2 to 7 μF/cm^2 rapidly with the concentration varying from 0 to 20 mL/L, because hydrogen inhibitor chemically adsorbs on active points of Fe electrode surface selectively. Element S in hydrogen inhibitor with negative electricity and strong capacity of offering electron shares isolated electrons with Fe. The adsorption of H atom is inhibited when adsorbing on active points of Fe electrode surface firstly, and then current efficiency of Zn-Fe alloy electroplating is improved accordingly. 展开更多
关键词 Zn-Fe alloy electroplating current efficiency hydrogen inhibitor MECHANISM
下载PDF
Investigation of electron cyclotron current drive efficiency on the J-TEXT tokamak
16
作者 Jiangang FANG Wei YAN +22 位作者 Zhongyong CHEN Xiaobo ZHANG Xixuan CHEN Junli ZHANG Feiyue MAO You LI Lingke MOU Yu ZHONG Feng Li Weikang ZHANG Fanxi LIU Guinan ZOU Song ZHOU Da LI Li GAO Donghui XIA Zhoujun YANG Zhipeng CHEN Nengchao WANG Yonghua DING Yunfeng LIANG Yuan PAN the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第12期183-189,共7页
Electron cyclotron current drive(ECCD) efficiency research is of great importance for the neoclassical tearing mode(NTM) stabilization.Improving ECCD efficiency is beneficial for the NTM stabilization and the ECCD pow... Electron cyclotron current drive(ECCD) efficiency research is of great importance for the neoclassical tearing mode(NTM) stabilization.Improving ECCD efficiency is beneficial for the NTM stabilization and the ECCD power threshold reduction.ECCD efficiency has been investigated on the J-TEXT tokamak.The electron cyclotron wave(ECW) power scan was performed to obtain the current drive efficiency.The current drive efficiency is derived to be approximately η_(0)=(0.06-0.16)×10^(19)A m^(-2)W^(-1)on the J-TEXT tokamak.The effect of the residual toroidal electric field has been included in the determination of the current drive efficiency,which will enhance the ECCD efficiency.At the plasma current of I_(p)=100 kA and electron density of n_(e)=1.5×10^(19)m^(-3),the ratio of Spitzer conductivity between omhic(OH)and ECCD phases is considered and the experimental data have been corrected.The correction results show that the current drive efficiency η_(1)caused by the fast electron hot conductivity decreases by approximately 79%.It can be estimated that the driven current is approximately 24 kA at 300 kW ECW power. 展开更多
关键词 electron cyclotron current drive current drive efficiency residual toroidal electric field
下载PDF
Guide Vane with Current Plate to Improve Efficiency of Cross Flow Turbine 被引量:1
17
作者 Kiyoshi Kokubu Toshiaki Kanemoto Keisuke Yamasaki 《Open Journal of Fluid Dynamics》 2013年第2期28-35,共8页
To get the sustainable society, the hydropower with not only the large but also the small/mini/micro capacities has been paid attention to in the power generation. The cross flow turbine can work effectively at the co... To get the sustainable society, the hydropower with not only the large but also the small/mini/micro capacities has been paid attention to in the power generation. The cross flow turbine can work effectively at the comparatively low head and/or low discharge, then the runner and the turbine profile has been optimizing. In this paper, the model turbine was prepared in accordance with the traditional design, and the performance and the flow condition were investigated experimentally at the various operating conditions. The hydraulic efficiency is doubtlessly maximal while the guide vane is at the normal/design position, and deteriorates in the lower discharges adjusted by the guide vane. Such deteriorations are brought from the unacceptable flow conditions in the inlet nozzle. To improve the efficiency dramatically in the lower discharge, the guide vane installed in the inlet nozzle was equipped with the current plate, and the fruitful effects of the plate on the efficiency were confirmed experimentally. 展开更多
关键词 HYDRAULIC TURBINE Cross Flow TURBINE Guide VANE INLET NOZZLE HYDRAULIC efficiency Discharge
下载PDF
Current diffusion and efficiency droop in vertical light emitting diodes
18
作者 R Q Wan T Li +6 位作者 Z Q Liu X Y Yi J X Wang J H Li W H Zhu J M Li L C Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第1期561-569,共9页
Current diffusion is an old issue, nevertheless, the relationship between the current diffusion and the efficiency of light emitting diodes(LEDs) needs to be further quantitatively clarified. By incorporating current ... Current diffusion is an old issue, nevertheless, the relationship between the current diffusion and the efficiency of light emitting diodes(LEDs) needs to be further quantitatively clarified. By incorporating current crowding effect(CCE) into the conventional ABC model, we have theoretically and directly correlated the current diffusion and the internal quantum efficiency(IQE), light extraction efficiency(LEE), and external quantum efficiency(EQE) droop of the lateral LEDs.However, questions still exist for the vertical LEDs(V-LEDs). Here firstly the current diffusion length L_s(I) and L_s(II) have been clarified. Based on this, the influence of CCE on the EQE, IQE, and LEE of V-LEDs were investigated. Specifically to our V-LEDs with moderate series resistivity, L_s(III) was developed by combining L_s(I) and L_s(II), and the CCE effect on the performance of V-LEDs was investigated. The wall-plug efficiency(WPE) of V-LEDs ware investigated finally. Our works provide a deep understanding of the current diffusion status and the correlated efficiency droop in V-LEDs, thus would benefit the V-LEDs' chip design and further efficiency improvement. 展开更多
关键词 efficiency droop VERTICAL light EMITTING diodes current CROWDING effect current BLOCKING layer
下载PDF
A Study of Energy Conversion Efficiency Versus Plasma Density by Lower Hybrid Current Drive in HT-7 Tokamak
19
作者 丁伯江 匡光力 +14 位作者 刘岳修 刘登成 单家方 刘甫坤 沈慰慈 石跃江 吴振伟 林建安 俞家文 徐汉东 商连全 张晓东 刘小宁 赵燕平 李建刚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2002年第3期1269-1274,共6页
Ramp-up experiments by means of lower hybrid wave on HT-7 superconducting tokamak have been performed and analyzed. A ramp-up rate of over 300 kA/s is obtained and a conversion efficiency of over 1.0% has been achieve... Ramp-up experiments by means of lower hybrid wave on HT-7 superconducting tokamak have been performed and analyzed. A ramp-up rate of over 300 kA/s is obtained and a conversion efficiency of over 1.0% has been achieved during the ramp-up phase. The study of the dependence of conversion efficiency on plasma density shows that the conversion efficiency is affected by the driven current, which is mainly dominated by the competition of impurity concentration with wave accessibility condition. In addition, the effect of current profile may play an important role in determining the conversion efficiency. 展开更多
关键词 LHCD In A Study of Energy Conversion efficiency Versus Plasma Density by Lower Hybrid current Drive in HT-7 Tokamak HT
下载PDF
ELECTROCHEMICAL DETERMINATION OF CURRENT EFFICIENCY IN ALUMINIUM ELECTROLYSIS
20
作者 Tie Jun(Metallurgical Engineering Institute, North China University of Technology, Beijing 100041) Qiu Zhuxian(Department of Nonferrous Metallurgy, Northeastern University, Shenyang 110006) 《中国有色金属学会会刊:英文版》 CSCD 1995年第1期25-28,共4页
ELECTROCHEMICALDETERMINATIONOFCURRENTEFFICIENCYINALUMINIUMELECTROLYSISTie;Jun(MetallurgicalEngineeringInstit... ELECTROCHEMICALDETERMINATIONOFCURRENTEFFICIENCYINALUMINIUMELECTROLYSISTie;Jun(MetallurgicalEngineeringInstitute,NorthChinaUni... 展开更多
关键词 aluminium ELECTROLYSIS current efficiency current CHRONOPOTENTIOMETRY
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部