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Plasma Science and Technology 2007年第3期9卷 284-287页

作者：喻志农薛唯郑德修孙鉴 Department of Optical Engineering School of Information EngineeringBeijing Institute of TechnologyBeijing 100081China Institute of Electronic Physics and Device Xi'an Jiaotong UniversityXi'an 710049China

This study investigated the effects of annealing and discharging on the characteristics of MgO thin films prepared by ion beam-assisted deposition as a protective layer of AC-PDP. By an annealing process at a temperature of 450 ℃ for more than three hours, the crystallinity of the deposited MgO films was improved, but the surface of the （200）-oriented MgO thin films in the vicinity of the discharge electrodes, especially on the inner sides of the electrodes, was subjected to crack formation to the compressive stress of The failure mechanism of the MgO films plus the additional （200）-oriented MgO films was due compressive stress induced by the differences in the coefficient of thermal expansion between the electrode and the dielectric layer. In the discharging process, all MgO films were eroded unevenly, and the serious erosion occurred near the edges of the discharge electrodes. ATM（atomic force microscopy） images show that the eroded surface of the （200）-oriented MgO thin film is smoother than that of the （111）-oriented fihn. Also, the （200）-oriented MgO thin film shows an improved ability to resist ion erosion compared to the （111）-oriented film.

关键词： MgO thin film ion beam-assisted deposition annealing discharging

Response of flood discharging capacity to the deterioration of the lower Yellow River

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Science China(Technological Sciences) 2004年第z1期47卷 152-160页

作者： LI Wenxue1, LI Yong2, YAO Wenyi2, SU Yunqi2 & ZHANG Xiaohua2 1. Yellow River Engineering Consulting Co. Ltd., Zhengzhou 450003, China 2. Yellow River Institute of Hydraulic Research, Zhengzhou 450003, China Yellow River Engn Consulting Co Ltd Zhengzhou 450003 Peoples R China Yellow River Inst Hydraul Res Zhengzhou 450003 Peoples R China

Based on the clarifications of the deterioration characteristics of the lower Yellow River (LYR), the influence of river deterioration on flood discharging capacity is studied through theoretical derivation and analysis of field data. This study indicates that response of flood discharging capacity to river deterioration is nonlinear. Sediment depositions in the main channel cause the reductions of dominant discharge and thus the increase of initial flood stage. Reductions in the channel width result in the increases of the rising rate of flood stage and the decrease of flood discharging capacity.

关键词： flood discharging capacity, boundary condition, deterioration, sediment, the lower Yellow River.

A fast and efficient coordinated vehicle-to-grid discharging control scheme for peak shaving in power distribution system

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Journal of Modern Power Systems and Clean Energy 2018年第3期6卷 555-566页

作者： Nuh ERDOGAN Fatih ERDEN Mithat KISACIKOGLU Department of Electrical Engineering University of Texas at Arlington Department of Electrical and Electronics Engineering Bilkent University Department of Electrical and Computer Engineering University of Alabama

This study focuses on the potential role of plugin electric vehicles(PEVs) as a distributed energy storage unit to provide peak demand minimization in power distribution systems. Vehicle-to-grid(V2 G) power and currently available information transfer technology enables utility companies to use this stored energy. The V2 G process is first formulated as an optimal control ***, a two-stage V2 G discharging control scheme is proposed. In the first stage, a desired level for peak shaving and duration for V2 G service are determined off-line based on forecasted loading profile and PEV mobility model. In the second stage, the discharging rates of PEVs are dynamically adjusted in real time by considering the actual grid load and the characteristics of PEVs connected to the grid. The optimal and proposed V2 G algorithms are tested using a real residential distribution transformer and PEV mobility data collected from field with different battery and charger ratings for heuristic user case scenarios. The peak shaving performance is assessed in terms of peak shaving index and peak load reduction. Proposed solution is shown to be competitive with the optimal solution while avoiding high computational loads. The impact of the V2 G management strategy on the system loading at night is also analyzed by implementing an off-line charging scheduling algorithm.

关键词： Distribution transformer Optimal discharging control Peak shaving Plug-in electric vehicles Vehicle-togrid

Hydrochemical and isotope characteristics of spring water discharging from Qiushe Loess Section in Lingtai, northwestern China and their implication to groundwater recharge

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Journal of Groundwater Science and Engineering 2017年第4期5卷 364-373页

作者： SONG Chao HAN Gui-lin WANG Pan SHI Ying-chun HE Ze The Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences School of Water Resources and Environment China University of Geosciences (Beijing)

The loess plateau in northwestern China with an area of 640 000km^2, which has developed the loess deposits with a thickness up to 200m in typical areas, is regarded as a huge carbon stock like the karst area in southwestern China, and plays an important role in regional(even global) carbon cycle. But the spring discharging from loess is poorly known compared with karst spring so far. The objective of this study is to ascertain the characteristics and origin of spring at Qiushe Village, Lingtai County, Gansu Province by hydro-chemical and isotopic methods. The results show that the springs including LGQ, HMQ, YYQ and CZQ are the depression spring and belong to the same shallow aquifer with the well water JZJ. There are not distinct seasonal/diurnal-scale variations on the hydro-chemical characteristics of the spring water(LGQ, HMQ, YYQ, CZQ) and groundwater(JZJ). The hydro-chemical type of groundwater is Ca·Mg-HCO_3. The D and O isotope ratios indicate that the precipitation is the main recharge source of groundwater in study area. And the results of tritium(TU) and Cl concentration suggest that the recharge cycle of groundwater may be more than 60 yrs. Our study shows that the water cycle in loess plateau including rainfall, infiltration, recharge and discharge exerts a continuous impact on carbon stock in loess, which should be paid more attention to in future research on the quantitative reconstruction of paleoclimate.

关键词： Spring discharging from loess Origin Precipitation Hydrochemistry Shallow groundwater

discharging FUNCTION AND THE THREE COLOUR PROBLEM

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青岛大学学报（自然科学版） 1999年第1期12卷 6-8页

作者：王春杰青岛大学数学系

由于Ｇｒｏｔｚｓｃｈ，下面的构形是三色可约的：一个五边形连接４个３度的顶点．在Ｇｒｏｔｚｓｃｈ三色定理和Ｇｒｕｎｂａｕｍ三色定理的证明过程中，证明上述构形的存在性是关键的一步．本文运用ｄｉｓｃｈａｒｇｉｎｇ函数加以证明．

关键词：三色定理三色问题图论 discharging 函数

Ecological Design of Flood discharging Canals in Shijiazhuang City

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Journal of Landscape Research 2009年第5期1卷 1-6,17页

作者：伊红珊刘辉芳河北政法职业学院园林系河北石家庄050061

From the perspective of ecological conservation and satisfaction of people's visual and psychological demands,existing problems in the urban revetment were analyzed,and the connotation of ecological revetment as well ... 详细信息

关键词： Garden Flood discharging canal Revetment Landscape

Study on performance of a packed bed latent heat thermal energy storage unit integrated with solar water heating system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第8期7卷 1422-1430页

作者： NALLUSAMY N SAMPATH S. VELRAJ R. Department of Mechanical Engineering Sri Venkateswara College of Engineering Chennai 602 105 India Department of Automobile Engineering Sri Venkateswara College of Engineering Chennai 602 105 India Institute for Energy Studies College of Engineering Guindy Anna University Chennai 600 025 India

In thermal systems such as solar thermal and waste heat recovery systems, the available energy supply does not usually coincide in time with the process demand. Hence some form of thermal energy storage (TES) is necessary for the most effective utilization of the energy source. This study deals with the experimental evaluation of thermal performance of a packed bed latent heat TES unit integrated with solar flat plate collector. The TES unit contains paraffin as phase change material (PCM) filled in spherical capsules, which are packed in an insulated cylindrical storage tank. The water used as heat transfer fluid (HTF) to transfer heat from the solar collector to the storage tank also acts as sensible heat storage material. Charging experiments were carried out at varying inlet fluid temperatures to examine the effects of porosity and HTF flow rate on the storage unit performance. The performance parameters such as instantaneous heat stored, cumulative heat stored, charging rate and system efficiency are studied. discharging experiments were carried out by both continuous and batchwise processes to recover the stored heat, and the results are presented.

关键词： Charging discharging Heat transfer fluid (HTF) Latent heat Phase change material (PCM) Packed bed Thermalenergy storage (TES)

Factors influencing the pumpability of unclassified tailings slurry and its interval division

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International Journal of Minerals,Metallurgy and Materials 2019年第4期26卷 417-429页

作者： Peng Li Yun-bing Hou Mei-feng Cai School of Civil and Resource Engineering University of Science and Technology Beijing Key Laboratory of High-Efficient Mining and Safety of Metal Mines (Ministry of Education of China) University of Science and Technology Beijing Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology Beijing School of Resource and Safety Engineering China University of Mining and Technology (Beijing)

Tailings consolidation and discharging technology is currently a popular means for disposing tailings in China. In this study, we describe a laboratory investigation of the unclassified tailings slurry from an iron mine and analyze the influence of the concentration,amount of consolidation agent, and types of consolidation agent on the pumpability in terms of the slump, slump flow, and bleeding rate of the slurry. The results indicate that an increase in concentration leads to a pronounced decrease in the magnitude of the slump, slump flow,and the bleeding rate. Compared with the consolidation agents P.O42.5 and P.S.A32.5, the new consolidation agent offers substantial advantages in promoting the pumping performance of the slurry. The concentration more strongly affects the slump, slump flow, and the bleeding rate of the slurry than does the amount of the consolidation agent. We also constructed the pumpability interval of the slurry on the basis of the slump and bleeding rate and accordingly determined the proportioning parameters of the slurry with a concentration of 75 wt% to79 wt% and with a consolidation agent concentration of 2 wt%. In addition, we discussed the pumpability mechanism of the slurry.

关键词： tailings consolidation and discharging technology unclassified tailings new consolidation agent pumpability interval pumpability mechanism

1-planar Graphs without 4-cycles or 5-cycles are 5-colorable

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 169-177页

作者： Li-li SONG Lei SUN Department of Mathematics and Statistics Shandong Normal UniversityJinan 250358China

A graph is 1-planar if it can be drawn on the Euclidean plane so that each edge is crossed by at most one other edge.A proper vertex k-coloring of a graph G is defined as a vertex coloring from a set of k colors such that no two adjacent vertices have the same color.A graph that can be assigned a proper k-coloring is k-colorable.A cycle is a path of edges and vertices wherein a vertex is reachable from itself.A cycle contains k vertices and k edges is a *** this paper,it is proved that 1-planar graphs without 4-cycles or 5-cycles are 5-colorable.

关键词： 1-planar colorable discharging vertices faces

Prediction of gas pulsation of an industrial compressor

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Journal of Central South University 2013年第10期20卷 2735-2740页

作者： Heuicheol Kim Mi-Gyung Cho Jaehong Park Cheolho Bai Jaesool Shim School of Mechanical Engineering Yeungnam University Department of Media Engineering Tongmyong University MEMS-Bio Team Korea National NanoFab Center 305 806 Korea

The measurement and prediction of gas pulsations are performed along the discharge pipeline of a reciprocating compressor for a refrigerator. A regression based experimental model of the one-dimensional acoustic field is developed. First, the conventional method for gas pulsation measurement and prediction, which separates the incident and reflected wave of acoustic waves traveling in the frequency domain, is discussed. Then, regression based on our proposed simple model, which is able to predict gas pulsation compared to the conventional method, is introduced for the analysis of a reciprocating compressor(The conventional method requires the value of sound speed in the piping line for the reciprocating compressor). A numerical prediction is made for the regression method. Three power spectrum values along the discharge pipeline are used for analysis, and two values are used for verification. Our results are in a good agreement with the conventional method.

关键词： gas pulsation reciprocating compressor discharging piping line regression model