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ASSESSMENT OF MILITARY AIRFIELD OBSTACLE FREE SPACE BASED ON GIS 被引量:5
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作者 罗成立 蔡良才 +3 位作者 黄命辉 鲁洋 刘莉莉 李鹏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第3期294-299,共6页
A mathematical model of obstacle limit surfaces for military airfield obstacle free space is established through airfield obstacle free space analysis.Based on the model,triangle mesh elevation model of military airfi... A mathematical model of obstacle limit surfaces for military airfield obstacle free space is established through airfield obstacle free space analysis.Based on the model,triangle mesh elevation model of military airfield obstacle free space is built by using the software-ArcGIS,and the 3-D display result is obtained.It is convenient to evaluate military airfield obstacle for superimposing digital elevation model(DEM)with military airfield topographic map.Thus it improves the efficiency greatly.It lays the foundation for the application of geographic information systems(GIS)in the management of military airfield obstacle free space. 展开更多
关键词 airfield obstacle free space mathematical model 3-D visualization geographic information system(GIS)
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中国近代商业史统计资料——煤的贸易与价格(二)
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作者 唐传泗 欧阳侃 《上海经济研究》 1984年第2期60-62,共3页
关键词 英吨 净数 口岸 海关 铁路 铁道 国产煤 中华人民共和国
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NUMERICAL SIMULATION AND EXPERIMENTS OF THE VECTOR-FLOW CLEANROOM
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作者 涂光备 陈文浩 王莱 《Transactions of Tianjin University》 EI CAS 2000年第1期50-54,共5页
Based on K ε two equation turbulence model,the air distribution and contamination field under different conditions was numerically simulated in a vector flow cleanroom.Special mesh system was introduced to deal wit... Based on K ε two equation turbulence model,the air distribution and contamination field under different conditions was numerically simulated in a vector flow cleanroom.Special mesh system was introduced to deal with the quarter circle shaped inlets.Model experiments were also made.By analysis of numerical as well as experimental results,we made some predictions about flow characteristics,contaminant control effect and ventilation performance of this energy saving cleanroom.It has been proved that the vector flow can meet class 100 of Fed. St.with 13 to 12 conventional air change per hour,and reduce layer height and simplify air clean system. 展开更多
关键词 vector flow CLEANROOM numerical simulation
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Simulating leaf net CO_2 assimilation rate of C_3 & C_4 plants and its response to environmental factors 被引量:1
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作者 张佳华 姚凤梅 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期9-12,共5页
Basic structure and algorithm of leaf mechanism photosynthesis model were described in first part of this study based on former researcher results. Then, considering some environmental factors influencing on leaf ph... Basic structure and algorithm of leaf mechanism photosynthesis model were described in first part of this study based on former researcher results. Then, considering some environmental factors influencing on leaf photosynthesis, three numerical sensitivity experiments were carried out. We simulated the sing le leaf net CO2 assimilation, which acts as a function of different light, carbo n dioxide and temperature conditions. The relationships between leaf net photosy nthetic rate of C3 and C4 plant with CO2 concentration intercellular, leaf tempe rature, and photosynthetic active radiation (PAR) were presented, respectively. The results show the numerical experiment may indicate the main characteristic o f plant photosynthesis in C3 and C4 plant, and further can be used to integrate with the regional climate model and act as land surface process scheme, and bett er understand the interaction between vegetation and atmosphere. 展开更多
关键词 Photosynthesis model Net CO2 assimilation rate C3 and C4 plants Num erical simulation
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Growth and yield of rice as affected by transplanting dates and seedlings per hill under high temperature of Dera Ismail Khan, Pakistan 被引量:3
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作者 BALOCH Mohammad Safdar AWAN Inayat Ullah HASSAN Gul 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第7期572-579,共8页
Studies were initiated for two consecutive years to find out the effect of time of transplanting and seedlings hill^-l on the productivity of rice in Dera Ismail Khan district of North West Frontier Province (NWFP),... Studies were initiated for two consecutive years to find out the effect of time of transplanting and seedlings hill^-l on the productivity of rice in Dera Ismail Khan district of North West Frontier Province (NWFP), Pakistan. The experiment was laid out in a randomized complete block design with split plot arrangements. Main plots consisted of four transplanting dates viz. 20th and 27th of June and 4th and 1 lth of July while sub-plots contained 1, 2, 3 or 4 seedlings hill^-1. Among transplanting dates, June 20th planted crop gave highest paddy yield and net return with I seedling hill^-1. It explains that the use of more seedlings hill^-1 not only adds to cost but is also a mere wastage of natural resources. Based on research findings, we conclude that the use of I seedling hill^-1 is most appropriate for timely sowing otherwise 4 seedlings hill^-1 should be used to compensate for the yield gap in late transplanted rice. 展开更多
关键词 RICE Transplanting time SEEDLINGS Yield Leaf area index Net assimilation rate
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The Impacts of Permafrost Change on NPP and Implications:A Case of the Source Regions of Yangtze and Yellow Rivers 被引量:9
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作者 FANG Yiping QIN Dahe +2 位作者 DING Yongjian YANG Jianping XU Keyan 《Journal of Mountain Science》 SCIE CSCD 2011年第3期437-447,共11页
This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolatin... This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolating functions,and non-linear regression methods.The source regions of the Yangtze and Yellow Rivers were selected as the research areas.Results illustrate that:(1) There is significant non-linear relationship between NPP and GT in various typical years;(2) The maximum value of NPP is 6.17,5.87,7.73,and 5.41 DM·t·hm-2 ·a-1 respectively,and the corresponding GT is 7.1,10.0,21.2,and 8.9 o C respectively in 1980,1990,2000 and 2007;(3) In 1980,the sensitivity of NPP to GT is higher than in 1990,2000 and 2007.This tendency shows that the NPP presents change from fluctuation to an adaptation process over time;(4) During 1980~2007,the accumulated NPP was reduced to 8.05,and the corresponding carrying capacity of theoretical livestock reduced by 11%;(5) The shape of the demonstration region of ecological compensation system,livelihood support system,and science appraisal system in the source regions of Yangtze and Yellow Rivers are an important research for increasing the adaptation capacity and balancing protection and development. 展开更多
关键词 The source regions of Yangtze and Yellow Rivers PERMAFROST Ground temperature (GT) Net primary productivity (NPP) Policy adaptation
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A novel purification process for dodecanedioic acid by molecular distillation 被引量:6
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作者 余江 袁希钢 曾爱武 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第3期499-504,共6页
A novel purification process is involved to obtain the high purity[>99%(by mass)]dodecanedioic acid(DC_(12)).It involves a re-crystallization followed by molecular distillation from the crude product.The objective ... A novel purification process is involved to obtain the high purity[>99%(by mass)]dodecanedioic acid(DC_(12)).It involves a re-crystallization followed by molecular distillation from the crude product.The objective of this study is to investigate general conditions,feed rate,distilling temperature and vacuum,necessary for centrifugal distillation of DC_(12).Under the optimum conditions,distilling temperature 180℃,pressure 30 Pa and feed flow rate700 ml·h^(-1),the purity of DC_(12) in the residence reached 97.55%with a yield of 53.18%by the analysis of gas chromatography.Multiple-pass distillation made a considerable contribution by improving the purity to99.22%.Additionally,the effect of pretreatment(re-crystallization) on distillation process was revealed through a series of comparative experiments. 展开更多
关键词 Dodecanedioic acid Fermentation Purification Separation Molecular distillation
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Simulating leaf net CO2 assimilation rate of C3 & C4 plants and its response to environmental factors 被引量:1
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作者 张佳华 姚凤梅 《Journal of Forestry Research》 CAS CSCD 2001年第1期9-12,75,共页
Basic structure and algorithm of leaf mechanism photosynthesis model were described in first part of this study based on former researcher results. Then, considering some environmental factors influencing on leaf ph... Basic structure and algorithm of leaf mechanism photosynthesis model were described in first part of this study based on former researcher results. Then, considering some environmental factors influencing on leaf photosynthesis, three numerical sensitivity experiments were carried out. We simulated the sing le leaf net CO2 assimilation, which acts as a function of different light, carbo n dioxide and temperature conditions. The relationships between leaf net photosy nthetic rate of C3 and C4 plant with CO2 concentration intercellular, leaf tempe rature, and photosynthetic active radiation (PAR) were presented, respectively. The results show the numerical experiment may indicate the main characteristic o f plant photosynthesis in C3 and C4 plant, and further can be used to integrate with the regional climate model and act as land surface process scheme, and bett er understand the interaction between vegetation and atmosphere. 展开更多
关键词 Photosynthesis model Net CO2 assimilation rate C3 and C4 plants Num erical simulation
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Vegetation NPP Distribution Based on MODIS Data and CASA Model——A Case Study of Northern Hebei Province 被引量:19
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作者 YUAN Jinguo NIU Zheng WANG Chenli 《Chinese Geographical Science》 SCIE CSCD 2006年第4期334-341,共8页
Net Primary Productivity (NPP) is one of the important biophysical variables of vegetation activity, and it plays an important role in studying global carbon cycle, carbon source and sink of ecosystem, and spatial a... Net Primary Productivity (NPP) is one of the important biophysical variables of vegetation activity, and it plays an important role in studying global carbon cycle, carbon source and sink of ecosystem, and spatial and temporal distribution of CO2. Remote sensing can provide broad view quickly, timely and multi-temporally, which makes it an attractive and powerful tool for studying ecosystem primary productivity, at scales ranging from local to global. This paper aims to use Moderate Resolution Imaging Spectroradiometer (MODIS) data to estimate and analyze spatial and temporal distribution of NPP of the northern Hebei Province in 2001 based on Carnegie-Ames-Stanford Approach (CASA) model. The spatial distribution of Absorbed Photosynthetically Active Radiation (APAR) of vegetation and light use efficiency in three geographical subregions, that is, Bashang Plateau Region, Basin Region in the northwestern Hebei Province and Yanshan Mountainous Region in the Northern Hebei Province were analyzed, and total NPP spatial distribution of the study area in 2001 was discussed. Based on 16-day MODIS Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) product, 16-day composite NPP dynamics were calculated using CASA model; the seasonal dynamics of vegetation NPP in three subreglons were also analyzed. Result reveals that the total NPP of the study area in 2001 was 25.1877 × 10^6gC/(m^2.a), and NPP in 2001 ranged from 2 to 608gC/(m^2-a), with an average of 337.516gC/(m^2.a). NPP of the study area in 2001 accumulated mainly from May to September (DOY 129-272), high NIP values appeared from June to August (DOY 177-204), and the maximum NPP appeared from late July to mid-August (DOY 209-224). 展开更多
关键词 NPP distribution MODIS data CASA model Northvrn Hebei Province
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A Study on Photosynthetic Physiological Characteristics of Six Rare and Endangered Species 被引量:1
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作者 Tailin ZHONG Guangwu ZHAO +2 位作者 Jiamiao CHU Xiaomin GUO Genyou LI 《Agricultural Science & Technology》 CAS 2014年第8期1265-1270,共6页
The parameters of gas exchange and chlorophyl fluorescence in leaves of six rare and endangered species Neolitsea sericea, Cinnamomum japonicum var. cheni , Sinojackia microcarpa, Discocleidion glabrum var. trichocarp... The parameters of gas exchange and chlorophyl fluorescence in leaves of six rare and endangered species Neolitsea sericea, Cinnamomum japonicum var. cheni , Sinojackia microcarpa, Discocleidion glabrum var. trichocarpum, Parrotia sub-aequalis, Cercidiphyl um japonicum were measured in fields. The results showed that there were significant differences in photosynthetic capacity, intrinsic water use effi-ciency (WUEi ), the efficiency of primary conversion of light energy of PSⅡ and its potential activity, the quantum yield of PSⅡ electron transport, and the potential ca-pacity of heat dissipation among the six species. However, there was no significant difference in WUE. The highest values of net photosynthetic rate (Pn), transpiration rate (Tr) and stomatal conductance (gs) occurred in D. glabrum var. trichocarpum and the lowest in S. microcarpa. On the contrary, D. glabrum var. trichocarpum had the lowest WUE, intrinsic water use efficiency (WUEi ) and S. microcarpa had the highest. The results indicated that D. glabrum var. trichocarpum had higher photo-synthetic capacity and poorer WUE, while S. microcarpa had lower photosynthetic capacity and greater WUE. Furthermore, the mean values of maximal fluorescence (Fm), potential efficiency of primary conversion of light energy of PSⅡ (Fv/Fm),ΦPSⅡ, actual efficiency of primary conversion of light energy of PSⅡ (F′v/F′m) and non-photochemical quenching coefficient (NPQ) were the highest in S. micro-carpa, indicating that its PSⅡ had higher capacity of heat dissipation and could prevent photosynthetic apparatus from damage by excessive light energy. Correlation analysis showed that there were significant correlations among photosynthetic physi-ological parameters. However, the initial fluorescence (Fo) was not significantly cor-related with any other parameters. This study also revealed the extremely significant positive correlations between Pn and Tr, gs, apparent quantum yield (AQY), be-tween Tr and gs, between light saturation point (LSP) and AQY, between Fv/Fm and Fm, between ΦPSⅡ and photochemical quenching coefficient (qp), between Tr, gs and LSP, AQY. However, WUEi was significantly negatively correlated with Tr, gs, Pn, LSP and AQY. 展开更多
关键词 Gas exchange Chlorophyll fluorescence Water use efficiency Rare andendangered species
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A preliminary study on air microorganism in a wood mill
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作者 ZOULi XUJi-fei +1 位作者 WANGXiang-li ZHENGHong 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第2期161-162,共2页
The air microbial species and quantities in a wood mill in Harbin, China weremeasured using sedimentation plate method. Results showed that the microbial quantity in the air atthe workshop without depurator (54939 cfu... The air microbial species and quantities in a wood mill in Harbin, China weremeasured using sedimentation plate method. Results showed that the microbial quantity in the air atthe workshop without depurator (54939 cfu·m^(-3)) was 2.1 times that of the workshop withdepu-rator (25768 cfu·m^(-3)). The depurator could purify air microorganisms at the workshop, witha purifying rate of 53.1%, but it did not reach the standards of clean air. Comparatively thedepurator is effective in reducing the quantity of air actinomyces, and some kinds of airactinomyces, such as Scabies, Cinereas and Hygroscopicas, can be clean out, but it is not veryeffective to bacteria and fungi. It is suggested that more effective and feasible methods should bedeveloped for purifying air microorganisms at the workshop in the future. 展开更多
关键词 air microorganism method of sedimentation plate purifying rate depurator
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IT Project Evaluation and Investment Decision 被引量:2
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作者 黄东兵 张世英 《Transactions of Tianjin University》 EI CAS 2004年第3期236-240,共5页
There are many kinds of real options,which are valuable,in each phase of the lifetime of an information technology(IT)project.However,in the current IT investment decision theory,real options that embedded in IT proje... There are many kinds of real options,which are valuable,in each phase of the lifetime of an information technology(IT)project.However,in the current IT investment decision theory,real options that embedded in IT projects are not considered. In this paper, the process of IT project decision and implementation is fully analyzed, the real options that may be embedded in an IT project are identified, and a real option analysis (ROA) method is proposed for evaluation of an IT project under uncertain business environment. ROA employs Black-Scholes expansion model and cancels the assumption that the cost of project is certain. The numerical example manifests that the ROA can better evaluate IT project and select the IT investment alternative. Finally, a road map is provided to help selecting the suitable evaluation method to make IT investment decision. 展开更多
关键词 information technology (IT) project total ownership cost (TOC) net present value (NPV) real option investment decision
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Numerical Simulation of Cold-Start Emission for the Three-Way Catalytic Converter: Mathematical Model and Result Analysis
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作者 吴国江 黄震 陈晓玲 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第3期363-371,共9页
This paper integrated a two-dimensional axisymmetrical transient model applicable to cold-start emission applications. The model can be used to simulate and explain effects of the flow and temperature distribution on ... This paper integrated a two-dimensional axisymmetrical transient model applicable to cold-start emission applications. The model can be used to simulate and explain effects of the flow and temperature distribution on performance of a converter. The evolutions of distribution of the temperature and concentration in the monolith during the cold-start period and the effects of flow distribution in the monolith on the cold-start performance are simulated in terms of the integrated model. The investigation indicates that the axial and radial gradients of temperature of the solid become steeper as the inlet gas temperature ramp increases; this furthermore results in the movement of reaction region in the monolith, and the flow distribution in the monolith affects the radial distribution of temperature of the solid;the radial gradients of temperature of the solid become greater as the flow uniformity index decreases, whereas the light-off time doesn't always increase as the flow uniformity index decreases. The analyses on the distribution of temperature and concentration in the monolith show that the catalytic reaction zone concentrates in central area near the front face. The predicted curves of the velocity distribution have a good agreement with the experimental data. 展开更多
关键词 cold start numerical simulation MODEL catalytic converter EMISSION flow distribution
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Prediction Model for Net Cutting Specific Energy in CNC Turning 被引量:3
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作者 ZHAO Guoyong LI Chunxiao +2 位作者 TIAN Yingzhou ZHANG Junfeng ZHAO Guangxi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第3期385-392,共8页
A prediction model for net cutting specific energy in computer numerical control(CNC)turning based on turning parameters and tool wear is developed.The model can predict the net cutting energy consumption before turni... A prediction model for net cutting specific energy in computer numerical control(CNC)turning based on turning parameters and tool wear is developed.The model can predict the net cutting energy consumption before turning.The prediction accuracy of the model is verified in AISI 1045 steel turning.The comparative experimental results show that the prediction accuracy of the model is significantly improved because the influence of tool wear is taken into account.Finally,the influences of turning parameters and tool wear on net cutting specific energy are studied.With the increase of cutting depth,the net cutting specific energy decreases.With the increase of spindle speed,the additional load loss power of spindle drive system increases,so the net cutting specific energy increases.The net cutting specific energy increases approximately linearly with tool wear.The results are helpful to formulate efficient and energy-saving CNC turning schemes and realize low‑carbon manufacturing. 展开更多
关键词 net cutting specific energy turning parameters tool wear processing scheme low‑carbon manufacturing
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Mathematical Simulation of Blood Purification for Leukemia by Immobilized L-asparaginase
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作者 金浩 方波 +2 位作者 江体乾 王铎林 周仕江 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第1期105-109,共5页
Plasma was purified in an immobilized L-asparaginase column. The predicted results are in good agreement with experimental data. It is indicated that the mathematical model is suitable for the mass transfer and react... Plasma was purified in an immobilized L-asparaginase column. The predicted results are in good agreement with experimental data. It is indicated that the mathematical model is suitable for the mass transfer and reaction of blood purification. 展开更多
关键词 BIOSEPARATION blood purification immobilized enzyme L-ASPARAGINASE
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Heavy Metal Analysis in Groundwater in the Vicinity of Distillery Spent Wash Evaporation Ponds
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作者 Muhammad Tariq Mahar Muhammad Yar Khuhawar +1 位作者 Taj Muhammad Jahangir Mushtaq Ahmad Baloch 《Journal of Chemistry and Chemical Engineering》 2013年第8期779-790,共12页
The study was conducted to assess the effect of evaporation ponds of an ethanol distillery spent wash on groundwater, with a reference to heavy metal contamination. The distillery discharging 11,880 m3 spent wash per ... The study was conducted to assess the effect of evaporation ponds of an ethanol distillery spent wash on groundwater, with a reference to heavy metal contamination. The distillery discharging 11,880 m3 spent wash per day is extremely loaded with minerals and chemical oxygen demanding organic substances. The groundwater around the evaporation ponds is used for drinking and irrigation purposes. Thirty-five representative samples (three spent wash, two drainage water and 30 groundwater) were examined for 13 different parameters: pH, TDS (total dissolved solids), COD (chemical oxygen demand), the heavy metal Cd, Co, Cr, Cu, Fe, Mn, Ni, Zn, Pb and As concentrations. The physico-chemical parameters were found in following range pH 7.2-7.7 & 6.8-7.7, TDS 24,448-28,608 mg/L & 302-4,406 mg/L, COD 20,080-24,320 mg/L & 0.0-53 mg/L, Cd 190-140 μg/L & 1.5-8.7 μg/L, Co 1,240-1,987 μg/L & 20.5-87.2 μg/L, Cr 1,020-1,330 μg/L & 14.4-38.1 μg/L, Cu 5,200-6,300 μg/L & 15.0-109.3 μg/L, Fe 2,910-3,242 μg/L & 0-860 μg/L, Mn 49,900-59,500 μg/L & 16.3-138.7 μg/L, Ni 1,430-1,760 μg/L & 8.0-107.7 μg/L, Zn 3,359-5,250 μg/L & 0.0-850 μg/L, Pb 8.9-9.8 μg/L & BD (below detection)-8.7 μg/L, As 5.0 μg/L & BD-10.0 μg/L for spent wash and groundwater samples, respectively. The drainage water samples had parameters within limits for industrial effluents. The spent wash samples contained metal ions higher than the permissible limits for industrial effluents and the samples of groundwater collected around the evaporation ponds contained higher concentrations of metal ions as compared to samples collected away from the evaporation ponds. Coefficient of correμtion among 11 parameters was calcuμted and contamination index was also determined, 33.3% of groundwater samples mostly collected around evaporation ponds had a contamination index above 3 and are considered extremely polluted. 展开更多
关键词 GROUNDWATER DISTILLERY spent wash heavy metal pollution.
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Numerical simulation of standing waves for ultrasonic purification of magnesium alloy melt 被引量:3
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作者 邵志文 乐启炽 +1 位作者 崔建忠 张志强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期382-387,共6页
It was attempted to enhance and accelerate the separation of oxidation inclusions from magnesium alloy melt by virtue of ultrasonic agglomeration technology.In order to investigate the feasibility and effectiveness of... It was attempted to enhance and accelerate the separation of oxidation inclusions from magnesium alloy melt by virtue of ultrasonic agglomeration technology.In order to investigate the feasibility and effectiveness of standing waves for ultrasonic purification of magnesium alloy melt,numerical simulation and relevant experiment were carried out.The numerical simulation was broken into two main aspects.On one hand,the ultrasonic field propagations within the cells with various shapes were characterized by numerical solutions of the wave equation and with a careful choice of geometry a nearly idealized standing wave field was finally obtained.On the other hand,within such a standing wave field the agglomeration behavior of oxidation inclusions in magnesium alloy melt was analyzed and discussed.The agglomeration time and agglomeration position of oxidation inclusions were predicted with numerical simulation method.The results show that the oxidation inclusions whose apparent densities are close to the density of the melt can agglomerate at wave nodes in a short time which to a great extent enhances and accelerates the separation of oxidation inclusions from magnesium alloy melt. 展开更多
关键词 magnesium alloy melt PURIFICATION standing waves numerical simulation
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Effect of climate change on seasonal water use efficiency in subalpine Abies fabri 被引量:4
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作者 SUN Xiang-yang WANG Gen-xu +2 位作者 HUANG Mei HU Zhao-yong SONG Chun-lin 《Journal of Mountain Science》 SCIE CSCD 2017年第1期142-157,共16页
Abies fabri is a typical subalpine dark coniferous forest in southwestern China. Air temperature increases more at high elevation areas than that at low elevation areas in mountainous regions,and climate change ratio ... Abies fabri is a typical subalpine dark coniferous forest in southwestern China. Air temperature increases more at high elevation areas than that at low elevation areas in mountainous regions,and climate change ratio is also uneven in different seasons. Carbon gain and the response of water use efficiency(WUE) to annual and seasonal increases in temperature with or without CO_2 fertilization were simulated in Abies fabri using the atmospheric-vegetation interaction model(AVIM2). Four future climate scenarios(RCP2.6,RCP4.5,RCP6.0 and RCP8.5) from the Coupled Model Intercomparison Project Phase 5(CMIP5) were selectively investigated. The results showed that warmer temperatures have negative effects on gross primary production(GPP) and net primary production(NPP) in growing seasons and positive effects in dormant seasons due to the variation in the leaf area index. Warmer temperatures tend to generate lower canopy WUE and higher ecosystem WUE in Abies fabri. However,warmer temperature together with rising CO_2 concentrations significantlyincrease the GPP and NPP in both growing and dormant seasons and enhance WUE in annual and dormant seasons because of the higher leaf area index(LAI) and soil temperature. The comparison of the simulated results with and without CO_2 fertilization shows that CO_2 has the potential to partially alleviate the adverse effects of climate warming on carbon gain and WUE in subalpine coniferous forests. 展开更多
关键词 Climate change Carbon gain Water use efficiency Atmospheric-vegetation interaction model
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Heat Transfer Performance of a Multi-heat Pipe Using Graphene Oxide/Water Nanofluid
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作者 Mohamed Salem Tarek A. Meakhail +1 位作者 Magdy A. Bassily Shuichi Torii 《Journal of Energy and Power Engineering》 2017年第2期95-102,共8页
A multi-heat pipe is a device for heat transmission. It is composed of a heating section, a cooling section and an adiabatic section. The heating and cooling sections are the same and both are connected by four circul... A multi-heat pipe is a device for heat transmission. It is composed of a heating section, a cooling section and an adiabatic section. The heating and cooling sections are the same and both are connected by four circular parallel tubes. This experimental study is performed to investigate heat transfer performance of a multi-heat pipe in the vertical orientation using pure water and GO (graphene oxide)/water nanofluid. GO/water nanofluids were synthesized by the modified Hummers method with 0.05%, 0.1%, 0.15%, and 0.2% volume concentrations. The thermal performance has been investigated with varying heat flux in the range of 10-30 W and 100% fill charge ratio. Wall temperature, thermal resistance, and heat transfer coefficient of the heat pipe are measured and compared with those for the heat pipe using pure water. The experimental results show that the evaporator wall temperature with GO nanofluid is lower than that of the base fluid. Also, the heat pipe that charged with nanofluids showed lower thermal resistance compared with pure water. Heat transfer enhancement is caused by suspended nanoparticles and is pronounced with the increase in particle volume fraction. 展开更多
关键词 NANOFLUID graphene oxide multi-heat pipe thermal performance.
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Study on the treatment of eutrophic water with a new integrative apparatus for water purification
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作者 WANG Li-ping XUE Chun-yang +2 位作者 GUO Ying-qing CHEN Yi-zhong GAO Nai-yun 《Journal of Environmental Science and Engineering》 2009年第7期6-10,共5页
This paper studied the treatment of the landscape river in ChangZhou Scientific and Educational Town by a new integrative apparatus for water purification, which used ozone pre-oxidation-moDified clay-ozone biological... This paper studied the treatment of the landscape river in ChangZhou Scientific and Educational Town by a new integrative apparatus for water purification, which used ozone pre-oxidation-moDified clay-ozone biological activated carbon integrated process. The results indicate that the effectiveness of the algal removal with mentioned integrated process is much higher and the apparatus can operate stably. When the turbidity, chemical oxygen demand (CODMn), total nitrogen (TN), total phosphorus (TP) and algae densities of the raw water are 29-38 NTU, 7.45-7.79 mg/L, 2.496-2.981 mag/L, 0.237-0.255 mg/L and 5.78-7.94×10^8 cells/L respectively, it can be reduced to 0.8-1.7 NTU, 1.69-2.84 rag/L, 0.579-0.692mg/L, 0.013-0.038 mg/L, 0.06-0.38×10^8 cells/L. The average removal rates of turbidity, CODMn, TN, TP and algae density can reach 96.4%, 71.5%, 76.8%, 92.0% and 96.9% respectively. The treated water can meet the requirements of class Ⅰ- Ⅱ in Environmental Quality Standard, for Surface Water. 展开更多
关键词 integrative apparatus for water purification ozone preoxidation modified clay ozone biological activated carbon
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