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解读单元考点,牵手高频考题——Unit 13 The Water Planet(英文)
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作者 彭定华 《中学生英语(高中版)》 2008年第8期14-15,共2页
人教版高二( 下) 册第十三单元的中心话题是 "水的星球", 不仅涉及水的化学结构、水的物理性质、水的用途、入海口、海洋等, 还涉及很多语法点、单词、短语、句型结构等, 下面就人教版高二 ( 下)Unit 13 TheWater Planet 的... 人教版高二( 下) 册第十三单元的中心话题是 "水的星球", 不仅涉及水的化学结构、水的物理性质、水的用途、入海口、海洋等, 还涉及很多语法点、单词、短语、句型结构等, 下面就人教版高二 ( 下)Unit 13 TheWater Planet 的重点语法、句型结构结合近几年高考试题做如下透视。 展开更多
关键词 宾语补足语 unit 13 The water Planet
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Three-dimensional physical simulation and optimization of water injection of a multi-well fractured-vuggy unit 被引量:6
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作者 Ji-Rui HOU Ze-Yu Zheng +4 位作者 Zhao-Jie Song Min LUO Hai-Bo Li Li Zhang Deng-Yu Yuan 《Petroleum Science》 SCIE CAS CSCD 2016年第2期259-271,共13页
With complex fractured-vuggy heterogeneous structures, water has to be injected to facilitate oil pro- duction. However, the effect of different water injection modes on oil recovery varies. The limitation of existing... With complex fractured-vuggy heterogeneous structures, water has to be injected to facilitate oil pro- duction. However, the effect of different water injection modes on oil recovery varies. The limitation of existing numerical simulation methods in representing fractured- vuggy carbonate reservoirs makes numerical simulation difficult to characterize the fluid flow in these reservoirs. In this paper, based on a geological example unit in the Tahe Oilfield, a three-dimensional physical model was designed and constructed to simulate fluid flow in a fractured-vuggy reservoir according to similarity criteria. The model was validated by simulating a bottom water drive reservoir, and then subsequent water injection modes were optimized. These were continuous (constant rate), intermittent, and pulsed injection of water. Experimental results reveal that due to the unbalanced formation pressure caused by pulsed water injection, the swept volume was expanded and consequently the highest oil recovery increment was achieved. Similar to continuous water injection, intermit- tent injection was influenced by factors including the connectivity of the fractured-vuggy reservoir, well depth, and the injection-production relationship, which led to a relative low oil recovery. This study may provide a constructive guide to field production and for the devel- opment of the commercial numerical models specialized for fractured-vuggy carbonate reservoirs. 展开更多
关键词 Multi-well fractured-vuggy unit Three-dimensional physical model Similarity criteria Bottom water drive. Optimization of water injection mode
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Comparison of water resources management between China and the United States 被引量:7
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作者 Chansheng He Carol P.Harden Yanxu Liu 《Geography and Sustainability》 2020年第2期98-108,共11页
As the world’s top two economies,the United States(U.S.)and China face a number of similar water resources problems.Yet,few studies have been done to systematically compare policies and approaches on water resources ... As the world’s top two economies,the United States(U.S.)and China face a number of similar water resources problems.Yet,few studies have been done to systematically compare policies and approaches on water resources management between China and the U.S.This study compares water resources policies of China and the U.S.in the areas of national authority,water supply,water quality,and ecosystem use of the water to draw lessons learned and shed light on water resources management in China,the U.S.,and the rest of the world.The lessons learned from the comparison include six aspects.1)New paradigms of people-water harmony and a water-saving society are urgently needed to address the pressing water crisis and achieve the United Nations Sustainable Development Goals(UN SDGs).2)A comprehensive,consistent,forward-looking national policy is necessary to achieve sustainable use of water resources.3)Empowerment of river basin commissions with comprehensive authority over the integrative management of air,land,water,and biological resources in the river basin could significantly enhance the benefits and effectiveness of economic development and environmental protection.4)Expansion of water exchange through market mechanisms among water users promotes efficient and beneficial water uses.5)Use of water for ecosystem services should be an integral part of water resources management.China has set up a national blueprint for achieving ecological civilization;maintaining appropriate amounts of flow in rivers and lakes for maintenance of wildlife and fisheries and ecosystems should be institutionalized as part of this national strategy as well.6)By sharing their rich experiences and lessons in water resources management,economic development,and ecological protection with other countries,China and the U.S.can help the world to achieve global human-water harmony and the UN SDGs. 展开更多
关键词 water resources management Comparative analysis China The united States
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An Overview of Conventional and Non-Conventional Water Resources in Arid Region: Assessment and Constrains of the United Arab Emirates (UAE) 被引量:1
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作者 Ahmed A. Murad 《Journal of Water Resource and Protection》 2010年第2期181-190,共10页
The aridity, population growth, agriculture and industrial activities threaten the water resources in the United Arab Emirates (UAE). In UAE, groundwater quantity is reduced and its quality is also deteriorated due to... The aridity, population growth, agriculture and industrial activities threaten the water resources in the United Arab Emirates (UAE). In UAE, groundwater quantity is reduced and its quality is also deteriorated due to the scanty of rainfall and over pumping for different uses. The deficit of groundwater is met by desalinated water and reused of treated wastewater. Agricultural activities have negative impacts on water resources and this causes reduction of groundwater quality as the agriculture the main land use in the UAE and it accounts for more than 70% of groundwater use. The treated wastewater is an alternative source for agricultural activities. To improve the current water situation, a national water resources strategy has been prepared and imple-mented to assist in achieve this target and maintain the country’s water security. This paper intends to give an overview of water resources in the UAE with emphasis on challenges facing the management of these resources. 展开更多
关键词 unitED Arab Emirates water Resources SUSTAINABILITY GROUNDwater Desalinated water
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Succession of aquatic microbial communities as a result of the water quality variations in continuous water 被引量:1
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作者 WANGRong-chang WENXiang-hua QIANYi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第5期772-778,共7页
The changes of structural and functional parameters of aquatic microbial communities in continuous water on campus of Tsinghua University, China are investigated by polyurethane foam unit(PFU) method. The measured com... The changes of structural and functional parameters of aquatic microbial communities in continuous water on campus of Tsinghua University, China are investigated by polyurethane foam unit(PFU) method. The measured compositions of the communities include alga, protozoa, and some metazoa(such as rotifers). The measured indicators of water quality include water temperature, pH value, dissolved oxygen(DO), potassium permanganate index(COD Mn ), total nitrogen(TN), total phosphorus(TP) and chlorophyll-a(Chla). The trophic level, expressed by the trophic level indices(TLIc), is assessed with analytic hierarchy process and principal component analysis(AHP-PCA) method. The changing trends of the structural and functional parameters of aquatic microbial communities, such as Margalef index of diversity(D), Shannon-weaver index of diversity (H), Heterotropy index(HI), number of species when the colonization gets equilibrium(S eq ), colonizing speed constant(G) and time spent when 90 percent of S eq colonized in PFU(T 90% ), are also analyzed. The experimental results showed the succession of aquatic microbial communities along the water flow is consistent with the water quality changes, so the parameters of microbial community can reflect the changes of water quality from the ecological view. 展开更多
关键词 SUCCESSION aquatic microbial community polyurethane foam unit(PFU) method water quality biodiversity BIOMONITORING
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Mixing and Vaporization Process of Injecting Water in Hydrogenation Unit 被引量:2
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作者 Liu Xiaofei Yu Chenyang +3 位作者 Zhu Haiyan Xu Henghui Jin Haozhe Wang Chao 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2021年第4期141-150,共10页
Injecting water into the main pipeline is a common method to prevent the ammonium salt corrosion in hydrogenation units.The use of spray nozzle can enhance the effects of washing ammonium salt and reduce the risk of a... Injecting water into the main pipeline is a common method to prevent the ammonium salt corrosion in hydrogenation units.The use of spray nozzle can enhance the effects of washing ammonium salt and reduce the risk of ammonium salt corrosion.The droplet atomization and evaporation model were used to investigate the mixing process of injecting water and gas-oil mixture in a high-pressure environment.The effects of some key parameters including fluid velocity,temperature,and droplet volume fraction on the mixing and vaporization process were analyzed.Numerical simulation results show that with the increase of injecting water flow rate,the fluid velocity increases and the temperature decreases continuously.When the mass flow rate of injecting water is 1.5 t/h,the droplet has the maximum evaporation efficiency and the volume fraction reaches a minimum value.Besides,with the increase of atomization angle and droplet size,the mean velocity and the temperature of fluid decrease continuously.The increase of atomization angle or the decrease of droplet size will accelerate the evaporation process of droplets and reduce the droplet volume fraction,which indicates that the droplet slip velocity and the contact area are the key factors affecting the droplet evaporation rate. 展开更多
关键词 water injection EVAPORATION numerical simulation hydrogenation unit
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Flow Calculation of Water Environmental Capacity Controlling Units in a Small Watershed Based on GIS Technology 被引量:1
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作者 LIU Chun-xiao WANG Li ZHANG Pei 《Meteorological and Environmental Research》 CAS 2012年第3期42-45,共4页
[Objeetive] We aimed to calculate the flow of controlling units in a small watershed based on GIS technology. [Method] Hydrologic analysis on Qingyi River was conducted by using ArcGIS9.0, and the controlling units wi... [Objeetive] We aimed to calculate the flow of controlling units in a small watershed based on GIS technology. [Method] Hydrologic analysis on Qingyi River was conducted by using ArcGIS9.0, and the controlling units with response of water-land were divided according to the riv- er monitoring sections of Xuchang City; considering the wastewater entering the river and the water from its upper reach, the runoff of controlling sections in the driest month ( with guarantee rate of 90% ) was calculated by means of isoline, runoff coefficient and hydrologic analogy method, and the calculated value of Gaocun Bridge section in Linying was contrasted with the measured value in 2010. [Result] The results showed that the cal- culated value and measured value of Gaecun Bridge section in Linying in the driest month of 2010 were 6.03 and 5.93 m^3/s respectively, with relative error of 1.69%, which revealed that the result of calculated runoff was reasonable. [ Conclusion] The way to divide controlling units was reason- able, and the calculation result of runoff was accurate and can meet the precision of water environment capacity calculation. 展开更多
关键词 water environmental capacity Controlling unit Runoff calculation China
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Hydrogeochemical Variations of Groundwater of the Northern Jabal Hafit in Eastern Part of Abu Dhabi Emirate, United Arab Emirates (UAE) 被引量:1
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作者 Ahmed Murad Faris Mahgoub Saber Hussein 《International Journal of Geosciences》 2012年第2期410-429,共20页
This study is aimed to assess and evaluate the suitability of groundwater of the area located to the south-east of Al-Ain area in the UAE using hydrogeochemcical approach. The chemical analyses of groundwater samples ... This study is aimed to assess and evaluate the suitability of groundwater of the area located to the south-east of Al-Ain area in the UAE using hydrogeochemcical approach. The chemical analyses of groundwater samples collected from the study area showed that the groundwater salinity is high which resulted from heavy groundwater pumping. High chloride concentrations in groundwater of Mubazarah and Neima might be attributed to the entrapped saline water within the limestone sequence of Jabal Hafit, or it can be the agricultural activities as it clear from the positive relationship between Cl- and Br-. High sulphate concentrations in groundwater might be related to the presence of gypsum and anhydrite within the limestone sequence of Jabal Hafit. The anionic and cationic compositions of groundwater indicate that the chloride and sodium ions are the dominant and presence of bicarbonate and sulphate may reflect the mixing of such water by the recent freshwater through the existing structural lineaments within the study area. The hydrochemical parameters indicate a relative increase in the concentration of calcium, magnesium and sulphate ions and this could reflect the influence of carbonates and evaporite sediments. 展开更多
关键词 unitED Arab Emirates SALINITY Major CATIONS and ANIONS GROUNDwater water Genesis
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Integrating Lithostratigraphic Units and GIS-Analysis Techniques to Modified Surface Water Quality Index 被引量:1
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作者 Majed Ibrahim Habes Al-Mashakbeh 《Journal of Environmental Protection》 2016年第8期1104-1112,共10页
The purpose of this study is to investigate the effect of using Bicarbonate and Calcium parameters as alternatives to the lithostratigraphic units covered the catchment area, on water quality index (WQI) values that h... The purpose of this study is to investigate the effect of using Bicarbonate and Calcium parameters as alternatives to the lithostratigraphic units covered the catchment area, on water quality index (WQI) values that have been implemented with GIS technique at Wadi Al-Arab Dam. The analyzed results (by WQI method) have been used to depict water quality for the two approaches. Based on physico-chemical parameters, the calculated values for WQI over the 3-year for study period were 169, 168, and 157, respectively. While the WQI values were 184, 183 and 172, respectively, as a result of incorporated Bicarbonate and Calcium parameters in WQI calculations that significantly contributed to increasing the WQI. The elevated values may be attributed to the influence of carbonate stone dissolution and mechanical erosion under weathering conditions that are prevalent during winter season in the catchment area. As a consequence of lithostratigraphic unites product and GIS technique integration and normalization processes, most of water quality ranks are good and only autumn season has poor water quality in the 2012 and 2013, while in 2014 it has good water quality in the same season. The WQI values increase in general trend from winter to autumn seasons during the study period that may be referred to outflow by daily consumption, evaporation rising, and seepage water. The analysis shows that the modified water quality values of the Wadi Al-Arab Dam Reservoir (WADR) vary after using Bicarbonate and Calcium parameters by constant value. Generally, the results signify that the WADR is not polluted based on the physical and chemical characteristics of water. 展开更多
关键词 GIS Lithostratigraphic units water Quality Index Surface water RESERVOIR SEASONALITY Irbid Wadi Al-Arab Dam JORDAN
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A Study on Water Demand Load Estimation by Using Unit of Living Water - Focused on Micro Water Supply Area in Daegu City
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作者 Ji-Soo Lee Won-Hwa Hong 《Journal of Environmental Protection》 2013年第1期23-30,共8页
Water supply capability has been significantly reduced as water demand has been increased due to changes of the world's weather, causing the increase of drought frequency, and urbanization. In terms of water produ... Water supply capability has been significantly reduced as water demand has been increased due to changes of the world's weather, causing the increase of drought frequency, and urbanization. In terms of water production, water can be secured by construction a dam or procuring substitute water. However, the study approaches in terms of management of water supply area to control the existing water efficiently. Therefore, water demand was estimated by buildings, by which water load of micro water supply area was calculated. As a result, the deviation of water demand for 1,357 micro water supply areas could be calculated while the alternatives to dissolve the spatial demand unbalance were suggested by two types. From the study, firstly, we could anticipate the total water supply demand from the total sum by filtration plants but it was not possible to anticipate the characteristics of distribution within urban areas. For this, the study attempted to anticipate the demand of each 250 thousands of buildings, comprehending the demand of micro areas. Secondly, based on the built results, we suggest the directions to dissolve the water demand unbalance between and among regions, which could be the foundation to suggest the concrete methodology in the future. 展开更多
关键词 water Supply Area water DEMAND Estimation Basic unit water for LIVING Smart water GRID
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Performance Simulation of H-TDS Unit of Fajr Industrial Wastewater Treatment Plant Using a Combination of Neural Network and Principal Component Analysis
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作者 Hamed Hasanlou Naser Mehrdadi +1 位作者 Mohammad Taghi Jafarzadeh Hamidreza Hasanlou 《Journal of Water Resource and Protection》 2012年第5期311-317,共7页
Nowadays, with regard to environmental issues, proper operation of wastewater treatment plants is of particular importance that in the case of inappropriate utilization, they will cause serious problems. Processes tha... Nowadays, with regard to environmental issues, proper operation of wastewater treatment plants is of particular importance that in the case of inappropriate utilization, they will cause serious problems. Processes that exist in environmental systems and environmental engineers are dealing with them mostly have two major characteristics: they are dependent on many variables;and there are complex relationships between its components which make them very difficult to analyze. Being familiar with characteristics of industrial town effluents from various wastewater treatment units, which have high qualitative and quantitative variations and more uncertainties compared to urban wastewaters, plays very effective role in governing them. In order to achieve a better and efficient control over the operation of an industrial wastewater treatment plant, powerful mathematical tool can be used that is based on recorded data from some basic parameters of wastewater during a period of treatment plant operation. In this study, the multilayer perceptron (MLP) feed forward neural network with a hidden layer and stop training method was used to predict quality parameters of the industrial effluent. Data of this study are related to the Fajr Industrial Wastewater Treatment Plant located in Mahshahr—Iran that qualitative and quantitative characteristics of its units were used for training, calibration and evaluation of the neural model. Also, Principal Component Analysis technique was applied to modify and improve performance of generated models of neural networks. The results of this model showed good accuracy of the model in estimating qualitative pro- file of wastewater. This model facilitates evaluating the performance of each treatment plant units through comparing the results of prediction model with the standard amount of output. 展开更多
关键词 Simulation Artificial NEURAL Network PCA Fajr Industrial WASTE water Treatment PLANT High TDS unit
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Unit13 The water planet 课本要点精练(英文)
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作者 罗毅 《中学生英语(高中版)》 2006年第8期13-15,48,共3页
关键词 unit13 The water planet
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Unit 2 Water sports
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作者 史晓春 《中学文科(初中语政外)》 2004年第7期34-35,共2页
关键词 unit2 water sports” 初中 英语 词汇 用法
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Unit 2 Water sports
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《中学课程辅导(初三版)》 2004年第7期15-15,共1页
关键词 unit2 water sports》 初三 英语 现在完成时 一般过去时 语法
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Unit 13 The water planet要点解读
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作者 李鹏 《中学生英语(高中版)》 2008年第8期4-6,共3页
一、词语例解1.benefitvt."有益于;有利于;对……有好处",后面接名词或代词Exercise benefits our health.锻炼对我们的健康有利。They are working together to benefit thewhole community.
关键词 定语从句 unit 13 The water planet 非谓语动词
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Unit13 The water planet 学习指导
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作者 甘占祖 《中学生英语(高中版)》 2006年第8期4-7,共3页
关键词 定语从句 unit13 The water planet
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Artificial Intelligence in Internet of Things System for Predicting Water Quality in Aquaculture Fishponds
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作者 Po-Yuan Yang Yu-Cheng Liao Fu-I Chou 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期2861-2880,共20页
Aquaculture has long been a critical economic sector in Taiwan.Since a key factor in aquaculture production efficiency is water quality,an effective means of monitoring the dissolved oxygen content(DOC)of aquaculture ... Aquaculture has long been a critical economic sector in Taiwan.Since a key factor in aquaculture production efficiency is water quality,an effective means of monitoring the dissolved oxygen content(DOC)of aquaculture water is essential.This study developed an internet of things system for monitoring DOC by collecting essential data related to water quality.Artificial intelligence technology was used to construct a water quality prediction model for use in a complete system for managing water quality.Since aquaculture water quality depends on a continuous interaction among multiple factors,and the current state is correlated with the previous state,a model with time series is required.Therefore,this study used recurrent neural networks(RNNs)with sequential characteristics.Commonly used RNNs such as long short-term memory model and gated recurrent unit(GRU)model have a memory function that appropriately retains previous results for use in processing current results.To construct a suitable RNN model,this study used Taguchi method to optimize hyperparameters(including hidden layer neuron count,iteration count,batch size,learning rate,and dropout ratio).Additionally,optimization performance was also compared between 5-layer and 7-layer network architectures.The experimental results revealed that the 7-layer GRU was more suitable for the application considered in this study.The values obtained in tests of prediction performance were mean absolute percentage error of 3.7134%,root mean square error of 0.0638,and R-value of 0.9984.Therefore,thewater qualitymanagement system developed in this study can quickly provide practitioners with highly accurate data,which is essential for a timely response to water quality issues.This study was performed in collaboration with the Taiwan Industrial Technology Research Institute and a local fishery company.Practical application of the system by the fishery company confirmed that the monitoring system is effective in improving the survival rate of farmed fish by providing data needed to maintain DOC higher than the standard value. 展开更多
关键词 FISHERY gated recurrent unit hyperparameter optimization long short-term memory Taguchi method water quality prediction
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Unit 13 The water planet课本要点精练(英文)
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作者 李灵恩 《中学生英语(高中版)》 2008年第8期12-13,48,共3页
Ⅰ.单词拼写根据句意、汉语或首字母的提示,写出所缺单词的完全形式。1.She dropped a(块)of sugar into hertea and stirred(搅拌)it with a spoon.2.People in the small island didn't
关键词 完成句子 unit 13 The water planet
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Study on Flow Unit of Heavy Oil Bottom Water Reservoir with Over-Limited Thickness in Offshore Oilfield
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作者 Wei Wang Jie Tan +2 位作者 Songru Mu Bo Li Wentong Zhang 《Open Journal of Geology》 2019年第9期507-515,共9页
The upper Ming section of L oilfield is a typical offshore heavy oil bottom-water reservoir with thick fluvial layers. All horizontal wells are developed by natural energy. Due to the few drilling holes and influence ... The upper Ming section of L oilfield is a typical offshore heavy oil bottom-water reservoir with thick fluvial layers. All horizontal wells are developed by natural energy. Due to the few drilling holes and influence by the resolution of seismic data, it is difficult to describe reservoirs with thickness over 20 meters. In this paper, seismic resonance amplitude inversion technology is introduced to restore the real response of thick reservoirs and interbeds by drilling and drilling verification, and the geological bodies with different thickness are displayed by frequency division RGB three primary colors. Flow units of heavy oil reservoirs with bottom water are divided according to the three major factors of interlayer, lithologic internal boundary and water-oil thickness ratio which have the greatest influence on horizontal well development, thick sand bodies are divided into 10 different flow units in three levels, each unit is separated from each other, and the reservoir structure, water-cut characteristics and water-flooding characteristics are different. The reliability of the research is improved by using the dynamic data of horizontal wells and newly drilled passing wells, which provides a basis for tapping the potential of heavy oil reservoirs with bottom water. 展开更多
关键词 Over-Limited THICK Layer INVERSION of Tuned Amplitude Frequency DIVISION RGB Fusion water-Oil Thickness Ratio Flow unit
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电化学水处理技术降低循环水硬度的实验研究 被引量:1
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作者 李火银 员佳琦 +3 位作者 李攀 程应伟 朱学智 于新功 《水处理技术》 CAS CSCD 北大核心 2024年第3期37-41,47,共6页
使用电化学法处理某焦化企业实际循环水的实验,探究了循环水的硬度和碱度去除率随处理时间的变化情况。分析了电流密度、水力停留时间、极板间距等实验操作参数以及商用阻垢剂对电解效果和能耗的影响。结果表明:硬度和碱度去除率随处理... 使用电化学法处理某焦化企业实际循环水的实验,探究了循环水的硬度和碱度去除率随处理时间的变化情况。分析了电流密度、水力停留时间、极板间距等实验操作参数以及商用阻垢剂对电解效果和能耗的影响。结果表明:硬度和碱度去除率随处理时间呈现先上升后平稳的趋势,且碱度去除率总是高于硬度去除率;电流密度为70 A/m^(2)、水力停留时间为6 min、极板间距为3 cm时电解效果最佳,硬度和碱度去除率可达27%以上,单位能耗低至13 kWh/kg;商用阻垢剂对电解效果具有阻碍作用。 展开更多
关键词 循环冷却水 电化学 电解效果 单位能耗 阻垢剂
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