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A comparative study of the land-atmosphere energy and water exchanges over the Tibetan Plateau and the Yangtze River Region
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作者 Nan Yao Yaoming Ma +3 位作者 Binbin Wang Jun Zou Jianning Sun Zhipeng Xie 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第2期52-59,共8页
正确认识不同区域能量和水分循环特征是研究局地地气相互作用及准确预测区域天气,气候变化的关键.为了研究属于干旱/半干旱气候的青藏高原(TP)和湿润/半湿润气候的长江流域(YRR)之间地表能量和水分交换的异同,本文对比分析了两个区域8... 正确认识不同区域能量和水分循环特征是研究局地地气相互作用及准确预测区域天气,气候变化的关键.为了研究属于干旱/半干旱气候的青藏高原(TP)和湿润/半湿润气候的长江流域(YRR)之间地表能量和水分交换的异同,本文对比分析了两个区域8个不同地表类型(包括高山荒漠,高山草地,(平原)城市和(平原)草地等)观测站点的地表辐射和能量通量数据.结果显示:(1)TP由于高原大气层稀薄且空气洁净,年平均入射短波辐射为251.3W m^(-2),是YRR的1.7倍.加之高原地表反照率高导致反射辐射(59.6 W m^(-2))是YRR的2.87倍.入射及出射的长波辐射为231.5和338.0 W m^(-2),分别为YRR的0.64和0.83.而两个区域的净辐射差异不大;(2)草地站更多的潜热释放使得地表总加热效率高于城市和高山荒漠,TP和YRR的草地站的年平均潜热分别为35.0和38.8 W m^(-2),而植被稀疏且土壤干燥的高山荒漠地区感热最大,年平均感热为42.1 W m^(-2);其次是城市下垫面,其年平均感热为37.7 W m^(-2).研究结果揭示了不同气候背景下典型下垫面地气相互作用特征,为地气相互作用过程深入分析奠定了基础. 展开更多
关键词 能量和水分交换 辐射分量 地表能量通量 青藏高原 长江流域 不同地表类型
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Advances in the Mechanisms of Hemorrhagic Transformation and Therapeutic Agents after Intravenous Thrombolysis in Ischemic Stroke
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作者 Yue Dai Yongyi Zhan +2 位作者 Mingtian Lu Zehua He Yu Liu 《Yangtze Medicine》 2024年第1期29-40,共12页
Ischemic stroke is an important disease leading to death and disability for all human beings, and the key to its treatment lies in the early opening of obstructed vessels and restoration of perfusion to the local infa... Ischemic stroke is an important disease leading to death and disability for all human beings, and the key to its treatment lies in the early opening of obstructed vessels and restoration of perfusion to the local infarcted area. Intravenous thrombolysis with tissue plasminogen activator (tPA) is one of the effective therapies to achieve revascularization, but it faces strict indications with a narrow therapeutic time window, and significantly increases the incidence of hemorrhagic transformation, HT, after reperfusion of the infarcted foci, which greatly reduces the incidence of patients with ischemic stroke. which significantly increases the incidence of hemorrhagic transformation (HT) after reperfusion of the infarcted focus, greatly reducing patient utilization and clinical benefit. Since the mechanism of HT has not been fully elucidated, and the related molecular mechanisms are complex and interactive, there is no specific and effective therapy to avoid the occurrence of HT. In this article, we focus on the research progress on the mechanism of HT after tPA intravenous thrombolysis in ischemic stroke patients from the aspects of vascular integrity disruption, oxidative stress, and neuroinflammatory response and the corresponding therapeutic strategies, in order to improve the safety and prognosis of tPA intravenous thrombolysis in the clinic. 展开更多
关键词 Hemorrhagic transformation Tissue-Type Fibrinogen Activator Acute Ischemic Stroke Blood-Brain Barrier
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Research Status of Water Quality Criteria and Standards and Analysis on the Transformation Methods
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作者 Cheng LI Yihong WU +1 位作者 Yang ZHAO Ruyu YUAN 《Meteorological and Environmental Research》 CAS 2023年第3期69-72,共4页
Under the vision of development for the new era,China has entered a stage of high-quality economic development and an important window period in which we have the conditions and ability to address the prominent issue ... Under the vision of development for the new era,China has entered a stage of high-quality economic development and an important window period in which we have the conditions and ability to address the prominent issue of economic development and ecological protection in a coordinated way.However,all kinds of environmental benchmark values in China are lacking and need to be constantly supplemented and improved.Therefore,exploring and putting forward a simple and efficient method for the transformation of environmental criteria into environmental standards is an important basis for the rapid establishment of relevant environmental criteria system and the effective promotion of the development of environmental standards system towards a scientific and reasonable direction.In this paper,the water environment is taken as the research object.By analyzing the research progress of environmental criteria and standards at home and abroad,and the foreign method of transforming environmental criteria into environmental standards,combined with the problems faced in the process of transforming environmental criteria into environmental standards in China,an effective method to transform China's environmental criteria into environmental standards is analyzed.After analysis and comparison,it is found that the pollution reduction accounting method could achieve their simple and efficient conversion.Under the premise of obtaining environmental criteria for certain pollutants,environmental criteria for certain pollutants could be obtained by distributing pollutants reduction costs,and accounting economic benefits after reaching standard,thus obtaining the environmental standard of this type of pollutant,which provides reference to determine the environmental standard limits of such pollutants. 展开更多
关键词 water quality criteria water quality standards Research status transformation mechanism
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Characteristics of Surface Water Quality Affected by Agricultural Non-point Sources in Guigang City 被引量:1
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作者 Yixin XU Peng ZHOU +1 位作者 Lei FENG Lifeng CHEN 《Asian Agricultural Research》 2023年第3期21-25,共5页
[Objectives]To analyze the influence characteristics of surface water quality by agricultural non-point sources in Guigang City of Guangxi.[Methods]The daily concentration series of water quality indicators at three s... [Objectives]To analyze the influence characteristics of surface water quality by agricultural non-point sources in Guigang City of Guangxi.[Methods]The daily concentration series of water quality indicators at three state-controlled monitoring stations in Guigang City from^(2)019 to 2021 was analyzed by using Daubechies(db)wavelet,and Morlet wavelet was used to analyze the daily average concentration of water quality indicators.Continuous wavelet transform(CWT)was used to analyze the monthly concentration series of water quality indicators at three state-controlled monitoring stations in Guigang City from^(2)014 to 2021.[Results]The Daubechies(db)wavelet analysis showed that the concentrations of COD_(Mn),TP,and TN had the maximum values during June-July and October-November,and there were spatial differences among monitoring stations(COD_(Mn) concentration exceeding the standard was the most serious in Shizui,and DO concentration not up to standard was the most in Thermal Power Plant,and NH_(3)-N,TP and TN exceeding the standard was the most in Wulin Ferry).Morlet results showed that principal period of wavelet variance graphs of COD_(Mn),NH_(3)-N,and TP was 340 d,and there was the same sub-period of 140 d,and principal period of wavelet variance graph of DO was 260 d.CWT results showed that COD_(Cr) had similar resonance periods of about 1-2 and 5-7 months;BOD 5 and COD_(Mn) was dominant by the resonance period of 1-4 months(2014-2017);DO had a similar resonance period of about 1-3 months;NH_(3)-N was dominant by the resonance period of 1-5 months.[Conclusions]The surface water quality of Guigang City was mainly affected by the residual nitrogen and phosphorus nutrients and pesticide residues from agricultural production activities. 展开更多
关键词 water quality Daubechies(db)wavelet Morlet wavelet Continuous wavelet transform(CWT)
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Numerical Simulation Analysis of the Transformer Fire Extinguishing Process with a High-Pressure Water Mist System under Different Conditions
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作者 Haowei Yao Youxin Li +7 位作者 Kefeng Lv Dong Wang Jinguang Zhang Zhenyu Zhan Zhenyu Wang Huaitao Song Xiaoge Wei Hengjie Qin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期733-747,共15页
To thoroughly study the extinguishing effect of a high-pressure water mist fire extinguishing system when a transformer fire occurs,a 3D experimental model of a transformer is established in this work by employing Fir... To thoroughly study the extinguishing effect of a high-pressure water mist fire extinguishing system when a transformer fire occurs,a 3D experimental model of a transformer is established in this work by employing Fire Dynamics Simulator(FDS)software.More specifically,by setting different parameters,the process of the highpressure water mist fire extinguishing system with the presence of both diverse ambient temperatures and water mist sprinkler laying conditions is simulated.In addition,the fire extinguishing effect of the employed high-pressure water mist system with the implementation of different strategies is systematically analyzed.The extracted results show that a fire source farther away fromthe centerline leads to a lower local temperature distribution.In addition,as the ambient temperature increases,the temperature above the fire source decreases,while the temperature and the concentrationof theupperflue gas layer bothdecrease.Interestingly,after thehigh-pressurewatermist sprinkler begins to operate,both the temperature distribution above the fire source and the concentration of the flue gas decrease,which indicates that the high-pressure water mist system plays the role of cooling and dust removal.By comparing various sprinkler laying methods,it is found that the lower sprinkler height has a better effect on the temperature above the fire source,the temperature of the upper flue gas layer,and the concentration of the flue gas.Moreover,when the sprinkler is spread over thewhole transformer,the cooling effect on both the temperature above the fire source and the temperature of the upper flue gas layer is good,whereas the change in the concentration of the flue gas above the fire source is not obvious compared to the case where the sprinkler is not fully spread. 展开更多
关键词 Transformer fire high-pressure water mist TEMPERATURE flue gas concentration
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A Water Level Forecast of Pattani River in the Southern of Thailand by Deep Learning
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作者 Prattana Deeprasertkul Kanoksri Sarinnapakorn 《Journal of Computer and Communications》 2023年第8期14-28,共15页
Nowadays, the deep learning methods are widely applied to analyze and predict the trend of various disaster events and offer the alternatives to make the appropriate decisions. These support the water resource managem... Nowadays, the deep learning methods are widely applied to analyze and predict the trend of various disaster events and offer the alternatives to make the appropriate decisions. These support the water resource management and the short-term planning. In this paper, the water levels of the Pattani River in the Southern of Thailand have been predicted every hour of 7 days forecast. Time Series Transformer and Linear Regression were applied in this work. The results of both were the water levels forecast that had the high accuracy. Moreover, the water levels forecasting dashboard was developed for using to monitor the water levels at the Pattani River as well. 展开更多
关键词 Time Series Transformer Linear Regression water Level Prediction Data Cleansing
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Research and Application of Ecological Outdoor Ground Structure with Composite Water Storage and Drainage Function
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作者 Peng ZHONG Yuqi FAN Zhenggen FAN 《Asian Agricultural Research》 2023年第10期6-9,共4页
In order to solve the problems of surface runoff increase,water accumulation in rainy days and urban heat island effect,an ecological outdoor ground structure with composite water storage and drainage functions was st... In order to solve the problems of surface runoff increase,water accumulation in rainy days and urban heat island effect,an ecological outdoor ground structure with composite water storage and drainage functions was studied and applied in this paper:Through the comprehensive design of road ground,road inspection well,garden inspection well and drainage pipe network,it can quickly store and drain ground water,alleviate the urban heat island effect,realize plant infiltration irrigation,and achieve the purpose of saving water and energy. 展开更多
关键词 Composite water storage and drainage waterlogging prevention Ecological type Outdoor ground
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Organic matter transformation ratio, hydrocarbon expulsion efficiency and shale oil enrichment type in Chang 7_(3) shale of Upper Triassic Yanchang Formation in Ordos Basin, NW China
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作者 ZHAO Wenzhi BIAN Congsheng +4 位作者 LI Yongxin LIU Wei DONG Jin WANG Kun ZENG Xu 《Petroleum Exploration and Development》 2023年第1期14-26,共13页
The major enrichment type of shale oil in the Chang 7_(3) shale of Upper Triassic Yanchang Formation in the Ordos Basin is unknown.This paper analyzes the organic matter transformation ratio,hydrocarbon expulsion effi... The major enrichment type of shale oil in the Chang 7_(3) shale of Upper Triassic Yanchang Formation in the Ordos Basin is unknown.This paper analyzes the organic matter transformation ratio,hydrocarbon expulsion efficiency and roof/floor sealing conditions of the Chang 7_(3) shale,and evaluates the major enrichment type of shale oil in this interval.The average organic matter transformation ratio of the Chang 7_(3) shale is about 45%;in other words,more than 50%of the organic matters have not transformed to hydrocarbons,and the lower the maturity,the greater the proportion of untransformed organic matters.The cumulative hydrocarbon expulsion efficiency of the transformed hydrocarbon is 27.5% on average,and the total proportion of untransformed organic matters plus retained hydrocarbons is greater than 70%.The relative hydrocarbon expulsion efficiency of the Chang 7_(3) shale is 60%on average,that is,about 40% of hydrocarbons retain in the shale.The Chang 7_(3) shale corresponds to Chang 7_(1+2) and Chang 8 sandstones as the roof and floor,respectively,and is further overlaid by Chang 6 shale,where extensive low porosity and low permeability–tight oil reservoirs have formed in the parts with relatively good porosity and permeability.Moreover,the Chang 7_(3) shale is tested to be in a negative pressure system(the pressure coefficient of 0.80–0.85).Therefore,the roof/floor sealing conditions of the Chang 7_(3) shale are poor.The retained hydrocarbons appear mostly in absorbed status,with low mobility.It is concluded that the medium–high mature shale oil is not the major enrichment type of shale oil in the Chang 7_(3) shale,but there may be enrichment opportunity for shale oil with good mobility in the areas where the sealing conditions are good without faults and fractures and oil reservoirs are formed off Chang 7_(1+2),Chang 6 and Chang 8.Furthermore,low–medium mature shale oil is believed to have great potential and is the major enrichment type of shale oil in the Chang 7_(3) shale.It is recommended to prepare relevant in-situ conversion technologies by pilot test and figure out the resource availability and distribution. 展开更多
关键词 organic matter transformation ratio hydrocarbon expulsion efficiency sealing condition continental shale oil major enrichment type Chang 7_(3)shale Triassic Ordos Basin
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Response of soil water dynamics to precipitation years under different vegetation types on the northern Loess Plateau, China 被引量:13
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作者 LIU Bingxia SHAO Ming'an 《Journal of Arid Land》 SCIE CSCD 2016年第1期47-59,共13页
Implementation of the Grain-for-Green project has led to rapid land cover changes and resulted in a significantly increased vegetation cover on the Loess Plateau of China during the past few decades. The main objectiv... Implementation of the Grain-for-Green project has led to rapid land cover changes and resulted in a significantly increased vegetation cover on the Loess Plateau of China during the past few decades. The main objective of this study was to examine the responses of soil water dynamics under four typical vegetation types against precipitation years. Soil water contents (SWCs) were measured in 0–4.0 m profiles on a hillslope under the four vegetation types of shrub, pasture, natural fallow and crop in a re-vegetated catchment area from April to October in normal (2010), dry (2011), wet (2014) and extremely wet (2013) years. The results indicated that precipitation and vegetation types jointly controlled the soil water temporal dynamics and profile characteristics in the study region. SWCs in 0–4.0 m profiles of the four vegetation types were ranked from high to low as crop>fallow>pasture>shrub and this pattern displayed a temporal stability over the four years. In the extremely wet year, SWC changes occurred in the 0–2.0 m layer under shrub and pasture while the changes further extended to the depth of 4.0-m deep layers under fallow and crop. In the other three years, SWCs changes mainly occurred in the 0–1.0 m layer and kept relatively stable in the layers deeper than 1.0 m for all the four vegetation types. The interannual variation in soil depth of SWCs was about 0–2.0 m for shrub and pasture, about 0–3.4 m for fallow and about 0–4.0 m for crop, respectively. The dried soil layers formed at the depths of 1.0, 0.6, 1.6 and 0.7 m under shrub, and 1.0, 1.0, 2.0 and 0.9 m under pasture, respectively in 2010, 2011, 2013 and 2014. The infiltrated rainwater mostly stayed in the 0–1.0 m layer and hardly supplied to soil depth >1.0 m in normal, dry and wet years. Even in the extremely wet year of 2013, rainwater recharge depth did not exceed 2.0 m under shrub and pasture. This implied that soil desiccation was difficult to remove in normal, dry and wet years, and soil desiccation could be removed in 1.0–2.0 m soil layers even in the extremely wet year under shrub and pasture. The results indicated that the natural fallow was the best vegetation type for achieving sustainable utilization of soil water and preventing soil desiccation. 展开更多
关键词 precipitation pattern RESTORATION soil water dynamics soil desiccation vegetation type
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CHARACTERISTICS OF WATER TRANSFORMATION AND ITS EFFECTS ON ENVIRONMENT IN THE ARID REGION —A case study in Alar irrigation region of Xinjiang, China 被引量:2
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作者 Xin Li Yu-dong Song Fu-hua Nian 《Chinese Geographical Science》 SCIE CSCD 2000年第1期53-61,共9页
The characteristics of water balance in arid regions is that the streams are formed in mountain area and continuously evaporates and infiltrates in the process of flowing to plain area, streams finally disappear in th... The characteristics of water balance in arid regions is that the streams are formed in mountain area and continuously evaporates and infiltrates in the process of flowing to plain area, streams finally disappear in the desert or flow into the lakes, which are the low reaches of the rivers. But the distribution and transformation of water in Xinjiang, China have changed under the influences of human activities. The influences of human activities take place in a short time and regionally, especially in arid land where water is the key factor of environment. Water inside of oasis has increased, and water out of oasis or at the lower reaches of the river has decreased. Human activities have caused the environment changes in both positive and negative aspects by changing the circulation and distribution of water. Under the influence of human activities, oases in Xinjiang have expanded, meanwhile some lakes have contracted desertification is serious, natural vegetation has declined and natural environment out of oasis has degenrated. 展开更多
关键词 ARID REGION water transformation human activity ENVIRONMENT
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Tuning electrochemical transformation process of zeolitic imidazolate framework for efficient water oxidation activity 被引量:1
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作者 Zhanwu Lei Xu Jin +4 位作者 Jianming Li Yang Liu Jian Liu Shuhong Jiao Ruiguo Cao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第2期505-513,共9页
Metal-organic frameworks(MOFs)have been widely studied as efficient electrocatalysts for water oxidation due to their tunable structure and easy preparation.However,the rational design of MOFs-based electrocatalysts a... Metal-organic frameworks(MOFs)have been widely studied as efficient electrocatalysts for water oxidation due to their tunable structure and easy preparation.However,the rational design of MOFs-based electrocatalysts and fundamental understanding of their structural evolution during oxygen evolution reaction(OER)remain critical challenges.Here,we report a facile approach to tune the structural transformation process of the Co-based zeolitic imidazolate framework(ZIF)during the OER process by using water molecules as a vacancy promoter.The modified ZIF catalyst accelerates the structural transformation from MOF precursor to electrochemical active species and simultaneously enhances the vacancy density during the electrochemical activation process.The optimized electrocatalyst exhibits an extremely low overpotential 175 mV to deliver 10 mA cm^(-2) and superior durability(100 h)at 100 mA cm^(-2).The comprehensive characterization results reveal the structural transformation from the initial tetrahedral Co sites to cobalt oxyhydroxide(CoOOH)and the formation process of oxygen vacancies(CoOOH-Vo)at a high anodic potential.These findings represent a promising way to achieve highly active MOF-based electrocatalysts for water oxidation. 展开更多
关键词 Metal-organic framework Structural transformation ELECTROCATALYST water splitting
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Water adsorption performance of UiO-66 modified by MgCl_(2) for heat transformation applications 被引量:1
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作者 刘佳丽 付国栋 +6 位作者 吴平 刘尚 杨金光 张师平 王立 许闽 淮秀兰 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期585-592,共8页
UiO-66 is a potential material for adsorption heat transformation(AHT)with high specific surface area,and excellent thermal and chemical stability.However,the low water adsorption capacity of UiO-66 in the low relativ... UiO-66 is a potential material for adsorption heat transformation(AHT)with high specific surface area,and excellent thermal and chemical stability.However,the low water adsorption capacity of UiO-66 in the low relative pressure range(0<P/P_(0)<0.3)limits its application in AHT.We prepare the UiO-66 modified by MgCl_(2)through using the solvothermal method and impregnation method,and study their water vapor adsorption performances and heat storage capacities.Attributed to the extremely high saturated water uptake and excellent hydrophilicity of MgCl_(2),the water adsorption performance of UiO-66 is improved,although the introduction of MgCl_(2)reduces its specific surface area and pore volume.The water adsorption capacity at P/P_(0)=0.3 and the saturated water adsorption capacity of the UiO-66(with MgCl_(2)content of 0.57 wt%)modified by the solvothermal method are 0.27 g/g and 0.57 g/g at 298 K,respectively,which are 68.8%and 32.6%higher than the counterparts of pure UiO-66,respectively.Comparing with pure UiO-66,the water adsorption capacity of the UiO-66(with MgCl_(2)content of 1.02 wt%)modified by the impregnation method is increased by 56.3%and 14.0%at the same pressure,respectively.During 20 water adsorption/desorption cycles,the above two materials show high heat storage densities(~1293 J/g and 1378 J/g).Therein,the UiO-66 modified by the solvothermal method exhibits the excellent cyclic stability.These results suggest that the introduction of an appropriate amount of MgCl_(2)makes UiO-66more suitable for AHT applications. 展开更多
关键词 adsorption heat transformation UiO-66 water vapor adsorption MgCl_(2)
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A Program Study of the Union of Semilattices on the Set of Subsets of Grids of Waterloo Language
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作者 Mikhail E. Abramyan Boris F. Melnikov 《Journal of Applied Mathematics and Physics》 2023年第5期1459-1470,共12页
The aim is to study the set of subsets of grids of the Waterloo language from the point of view of abstract algebra and graph theory. The study was conducted using the library for working with transition graphs of non... The aim is to study the set of subsets of grids of the Waterloo language from the point of view of abstract algebra and graph theory. The study was conducted using the library for working with transition graphs of nondeterministic finite automata NFALib implemented by one of the authors in C#, as well as statistical methods for analyzing algorithms. The results are regularities obtained when considering semilattices on a set of subsets of grids of the Waterloo language. It follows from the results obtained that the minimum covering automaton equivalent to the Waterloo automaton can be obtained by adding one additional to the minimum covering set of grids. . 展开更多
关键词 Nondeterministic Finite Automata Universal Automaton Basic Automaton Grid Covering Automaton Equivalent transformation Algorithms water-loo Automaton
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Impact of Urban Land Transformation on Water Bodies in Srinagar City, India
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作者 Shahab Fazal Arshad Amin 《Journal of Environmental Protection》 2011年第2期142-153,共12页
Human actions rather than natural forces are the source of most contemporary changes in the state and flows of the biosphere. Understanding these actions and the social forces that drive them is crucial to understandi... Human actions rather than natural forces are the source of most contemporary changes in the state and flows of the biosphere. Understanding these actions and the social forces that drive them is crucial to understanding, modelling and predicting local, regional as well as global environmental change and also for managing and responding to such change. The present study investigates the patterns of urban land transformation in Srinagar City, which lies in fragile hill eco-system of Kashmir valley. The results points towards unplanned and haphazard urban expansion and transformation. These transformations have severely destroyed the water bodies both in terms of area as well as its quality. 展开更多
关键词 Urban LAND transformation water BODIES AGRICULTURE Marshy
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Effects of muddy water irrigation with different sediment gradations on nitrogen transformation in agricultural soil of Yellow River Basin
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作者 Li-na Chen Zi-long Zhao +4 位作者 Guo-mian Guo Jiang Li Wen-bo Wu Fang-xiu Zhang Xiang Zhang 《Water Science and Engineering》 EI CAS CSCD 2022年第3期228-236,共9页
Muddy water irrigation has been widely practiced in the Yellow River Basin for agricultural production and is an important method of economical and intensive utilization of water resources.In this study,the effects of... Muddy water irrigation has been widely practiced in the Yellow River Basin for agricultural production and is an important method of economical and intensive utilization of water resources.In this study,the effects of sediment gradation,sand content,and soil moisture content on nitrogen(N)transformation were studied through a series of experimental tests.The results indicated that muddy water irrigation significantly affected agricultural soil physical and biological properties as well as N transformation.Soil bulk density,total porosity,pH,and microbial enzyme activities significantly correlated with N transformation as affected by the interaction between sediment and soil moisture.Sediment addition generally increased the soil bulk density and reduced the soil porosity and pH significantly,and the optimum moisture for promotion of the N transformation rate was 80%of the water-filled pore space.Therefore,muddy water irrigation has a potentially long-term influence on agricultural N cycles in semi-arid regions of northwestern China.This could provide a theoretical basis for scientific and rational use of muddy water for irrigation. 展开更多
关键词 Yellow River Basin Muddy water irrigation Soil properties Nitrogen transformation SEDIMENT
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Pore-Throat Combination Types and Gas-Water Relative Permeability Responses of Tight Gas Sandstone Reservoirs in the Zizhou Area of East Ordos Basin, China 被引量:5
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作者 LI Mi GUO Yinghai +2 位作者 LI Zhuangfu WANG Huaichang ZHANG Jingxia 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第3期622-636,共15页
With the aim of better understanding the tight gas reservoirs in the Zizhou area of east Ordos Basin,a total of 222 samples were collected from 50 wells for a series of experiments.In this study,three pore-throat comb... With the aim of better understanding the tight gas reservoirs in the Zizhou area of east Ordos Basin,a total of 222 samples were collected from 50 wells for a series of experiments.In this study,three pore-throat combination types in sandstones were revealed and confirmed to play a controlling role in the distribution of throat size and the characteristics of gas-water relative permeability.The type-I sandstones are dominated by intercrystalline micropores connected by cluster throats,of which the distribution curves of throat size are narrow and have a strong single peak(peak ratio>30%).The pores in the type-II sandstones dominantly consist of secondary dissolution pores and intercrystalline micropores,and throats mainly occur as slice-shaped throats along cleavages between rigid grain margins and cluster throats in clay cement.The distribution curves of throat size for the type-II sandstones show a bimodal distribution with a substantial low-value region between the peaks(peak ratio<15%).Primary intergranular pores and secondary intergranular pores are mainly found in type-III samples,which are connected by various throats.The throat size distribution curves of type-III sandstones show a nearly normal distribution with low kurtosis(peak ratio<10%),and the micro-scale throat radii(>0.5μm)constitute a large proportion.From type-I to type-III sandstones,the irreducible water saturation(Swo)decreased;furthermore,the slope of the curves of Krw/Krg in two-phase saturation zone decreased and the two-phase saturation zone increased,indicating that the gas relative flow ability increased.Variations of the permeability exist in sandstones with different porethroat combination types,which indicate the type-III sandstones are better reservoirs,followed by type-II sandstones and type-I sandstones.As an important factor affecting the reservoir quality,the pore-throat combination type in sandstones is the cumulative expression of lithology and diagenetic modifications with strong heterogeneity. 展开更多
关键词 tight gas sandstone pore-throat COMBINATION type THROAT characteristic GAS-water relative permeability Zizhou area ORDOS Basin
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Transformation of Nonlinear Surface Gravity Waves under Shallow-Water Conditions
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作者 Iftikhar B. Abbasov 《Applied Mathematics》 2010年第4期260-264,共5页
This article describes transformation of nonlinear surface gravity waves under shallow-water conditions with the aid of the suggested semigraphical method. There are given profiles of surface gravity waves on the cres... This article describes transformation of nonlinear surface gravity waves under shallow-water conditions with the aid of the suggested semigraphical method. There are given profiles of surface gravity waves on the crests steepening stages, their leading edges steepening. There are discussed the spectral component influence on the transformation of surface wave profile. 展开更多
关键词 NONLINEAR SURFACE GRAVITY WAVES SHALLOW-water Semigraphical Method transformation of SURFACE Wave Profile
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Numerical Simulation of Nonlinear Surface Gravity Waves Transformation under Shallow-Water Conditions
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作者 Iftikhar B. Abbasov 《Applied Mathematics》 2012年第2期135-141,共7页
This work considers the problems of numerical simulation of non-linear surface gravity waves transformation under shallow bay conditions. The discrete model is built from non-linear shallow-water equations. Are result... This work considers the problems of numerical simulation of non-linear surface gravity waves transformation under shallow bay conditions. The discrete model is built from non-linear shallow-water equations. Are resulted boundary and initial conditions. The method of splitting into physical processes receives system from three equations. Then we define the approximation order and investigate stability conditions of the discrete model. The sweep method was used to calculate the system of equations. This work presents surface gravity wave profiles for different propagation phases. 展开更多
关键词 Equations of SHALLOW-water Numerical Modelling NONLINEAR SURFACE GRAVITY WAVES transformation of SURFACE Wave Profile
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The construction types of inner river wharf with huge water fluctuation and their development
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作者 ZHU Yunfei 《International English Education Research》 2016年第4期1-1,共1页
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Photocatalytic Degradation of Water-Soluble Dyes by LaCoO_3 被引量:9
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作者 傅希贤 杨秋华 +2 位作者 王俊珍 白树林 桑丽霞 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第4期424-426,共3页
Perovskite type oxides LaCoO 3 was prepared by citrate method in granula of 20~30 nm. Using a fluorescent Hg lamp or sunlight as irradiator, the degradation experiments of various water soluble dyes were carried o... Perovskite type oxides LaCoO 3 was prepared by citrate method in granula of 20~30 nm. Using a fluorescent Hg lamp or sunlight as irradiator, the degradation experiments of various water soluble dyes were carried out in the suspension system of LaCoO 3. The results show that the perovskite type oxide LaCoO 3 has good photocatalytic activity. With the study of X ray photoelectron spectroscopy and photoacoustic spectra, its photocatalytic activity is mainly related with the factors such as the d electron structure of ion Co 3+ , Co O binding energy and adsorbed oxygen on the surface etc. 展开更多
关键词 catalytic chemistry water soluble dye perovskite type LaCoO 3 photocatalytic degradation rare earths
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