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A method of analysis of macro water environmental systems
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作者 Bao Jingling (Tianjin institute of Environment Protection Science, Tianjin 300191 China) Yang Baochen Zhang Shiying(Department of Engineering Economics & Systems Engineering,Tianjin University, Tianjin 300072, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第4期496-503,共8页
The phases of water environmental system (WES) and their emphatic intersections areanalysed in this paper. and from the view point of system analysis , an analytical process of WES is provided. Based on the balance ne... The phases of water environmental system (WES) and their emphatic intersections areanalysed in this paper. and from the view point of system analysis , an analytical process of WES is provided. Based on the balance network of WES, a goal programming model for regional water environmentalplanning and the main computational result for a coastal city are provided , thus proving its usefulness andeffectiveness. 展开更多
关键词 water environmental system balance network of water environmental system goal program-ming.
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A Scheme for a Sustainable Urban Water Environmental System During the Urbanization Process in China 被引量:6
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作者 Huibin Yu Yonghui Song +2 位作者 Xin Chang Hongjie Gao Jianfeng Peng 《Engineering》 2018年第2期26-29,共4页
Urbanization is a potential factor in economic development, which is a main route to social development. As the scale of urbanization expands, the quality of the urban water environment may deteriorate, which can have... Urbanization is a potential factor in economic development, which is a main route to social development. As the scale of urbanization expands, the quality of the urban water environment may deteriorate, which can have a negative impact on sustainable urbanization. Therefore, a comprehensive understanding of the functions of the urban water environment is landscape, culture, and economy. Furthermore, a the urban water environment, which is associated necessary, including its security, resources, ecology, deep analysis is required of the theoretical basis of with geographical location, landscape ecology, and a low-carbon economy. In this paper, we expound the main principles for constructing a system for the urban water environment (including sustainable development, ecological priority, and regional differ- ences), and suggest the content of an urban water environmental system. Such a system contains a nat- ural water environment, an economic water environment, and a social water environment. The natural water environment is the base, an effective economic water environment is the focus, and a healthy social water environment is the essence of such a system. The construction of an urban water environment should rely on a comprehensive security system, complete scientific theory, and advanced technology. 展开更多
关键词 URBANIZATION Urban water environment Water function Security system
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On division management for environmental system of China: lessons from European local sustainable development 被引量:1
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作者 Bai Yongqing Hao Jingxia Zhu Xiancheng 《Ecological Economy》 2006年第2期190-195,共6页
The concept of sustainable development, after being brousht forward, has become a shibboleth in the world, at national and local levels. In Europe, this concept is implemented from the local to tha nation, even to the... The concept of sustainable development, after being brousht forward, has become a shibboleth in the world, at national and local levels. In Europe, this concept is implemented from the local to tha nation, even to the Continent. The local sustainable development mainly consists in two factors: one is the renovating method continually invented by European Secretariot of ICLEI, and the other is that the local authorities towards sustainability are co-operated by the European Sustainable Cities and Towns Campaign. The coo-budget method is the outcome of tbese factors, For our country is a big country, on rapid progression of indastrialization and urbanization, with a large population and scarce resoarces per capita, it is practically significance to study us soon as possible the methodology. Experience from European local sustainable development may help us to resolve the handicap of departraent division in local a, tbority. 展开更多
关键词 Local sustainable development Europe China environmental management Department division
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Kalium Lakes:与Jaylon Environmental Systems达成合作
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作者 贾岩 《中国农资》 2019年第29期8-8,共1页
Kalium Lakes与Jaylon Environmental Systems达成合同,其中包括Kalium Lakes的Beyondie硫酸钾项目提供和安装蒸发池衬垫。2019年5月初,先支付100万澳元,作为早期工程的一部分,余额将在Kalium Lakes最终投资决定(FID)后开始支付。
关键词 硫酸钾 KALIUM LAKES Jaylon environmental systemS
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Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins
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作者 Daiyu Hu Yuanqing Cao +6 位作者 Chenglin Cai Guangming Wang Min Zhou Luying Peng Yantao Fan Qiong Lai Zhengliang Gao 《Neural Regeneration Research》 SCIE CAS 2025年第1期242-252,共11页
Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-li... Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies. 展开更多
关键词 cadmium cell death cell proliferation cortical development environmental toxins neural progenitor cells NEUROGENESIS NEUROTOXICOLOGY ORGANOIDS stem cells
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Research on the Relationship Between Environmental and Economic Coupling Systems in Bohai Bay Area Based on a Vector Autoregression(VAR)Model 被引量:1
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作者 CAO Huimin WANG Ping +2 位作者 ZHANG Surong XU Dongpo TIAN Weijun 《Journal of Ocean University of China》 CAS CSCD 2024年第2期557-566,共10页
This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,China.Based on panel data spanning 2011-2020,a vector autoregressive(V... This study analyzed the impact of land-based contaminants and tertiary industrial structure on economic development in the selected Bohai Bay area,China.Based on panel data spanning 2011-2020,a vector autoregressive(VAR)model is used to analyze and forecast the short-run and long-run relationships between three industrial structures,pollutant discharge,and economic development.The results showed that the environmental index had a long-term cointegration relationship with the industrial structure economic index.Per capital chemical oxygen demand(PCOD)and per capita ammonia nitrogen(PNH_(3)N)had a positive impact on delta per capita GDP(dPGDP),while per capita solid waste(PSW),the secondary industry rate(SIR)and delta tertiary industry(dTIR)had a negative impact on dPGDP.The VAR model under this coupling system had stability and credibility.The impulse response results showed that the short-term effect of the coupling system on dPGDP was basically consistent with the Granger causality test results.In addition,variance decomposition was used in this study to predict the long-term impact of the coupling system in the next ten periods(i.e.,ten years).It was found that dTIR had a great impact on dPGDP,with a contribution rate as high as 74.35%in the tenth period,followed by the contribution rate of PCOD up to 3.94%,while the long-term contribution rates of PSW,SIR and PNH3N were all less than 1%.The results show that the government should support the development of the tertiary industry to maintain the vitality of economic development and prevent environmental deterioration. 展开更多
关键词 Bohai Bay area environmental pollution industrial structure cointegration theory VAR model impulse response
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Optimizing Sustainability:Exergoenvironmental Analysis of a Multi-Effect Distillation with Thermal Vapor Compression System for Seawater Desalination
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作者 Zineb Fergani Zakaria Triki +5 位作者 Rabah Menasri Hichem Tahraoui Meriem Zamouche Mohammed Kebir Jie Zhang Abdeltif Amrane 《Frontiers in Heat and Mass Transfer》 EI 2024年第2期455-473,共19页
Seawater desalination stands as an increasingly indispensable solution to address global water scarcity issues.This study conducts a thorough exergoenvironmental analysis of a multi-effect distillation with thermal va... Seawater desalination stands as an increasingly indispensable solution to address global water scarcity issues.This study conducts a thorough exergoenvironmental analysis of a multi-effect distillation with thermal vapor compression(MED-TVC)system,a highly promising desalination technology.The MED-TVC system presents an energy-efficient approach to desalination by harnessing waste heat sources and incorporating thermal vapor compression.The primary objective of this research is to assess the system’s thermodynamic efficiency and environmental impact,considering both energy and exergy aspects.The investigation delves into the intricacies of energy and exergy losses within the MED-TVC process,providing a holistic understanding of its performance.By scrutinizing the distribution and sources of exergy destruction,the study identifies specific areas for enhancement in the system’s design and operation,thereby elevating its overall sustainability.Moreover,the exergoenvironmental analysis quantifies the environmental impact,offering vital insights into the sustainability of seawater desalination technologies.The results underscore the significance of every component in the MED-TVC system for its exergoenvironmental performance.Notably,the thermal vapor compressor emerges as pivotal due to its direct impact on energy efficiency,exergy losses,and the environmental footprint of the process.Consequently,optimizing this particular component becomes imperative for achieving a more sustainable and efficient desalination system. 展开更多
关键词 Exergoenvironmental analysis MED-TVC DESALINATION environmental impact of freshwater multi-objective optimization
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Opportunities to Improve the Quality of Environmental Reports and the Effectiveness of Environmental Impact Assessment: A Case of Electric Power Transmission Systems in Brazil
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作者 Vinícius Arthico Demori Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期124-140,共17页
A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international l... A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international literature has contributed to the understanding of the essential aspects to be verified regarding the quality of EIS, offering a wide spectrum of good practice examples related to the content of the studies. Even so, there is a need for empirical studies that allow the identification of specific aspects related to the context of application of the EIS, which could lead to the identification of opportunities to improve both the quality of the reports and also the effectiveness of EIA. Therefore, the present paper is focused on the quality review of a number of EIS submitted to the Brazilian Federal Environmental Agency (Ibama) to instruct the assessment of electric power transmission systems. Based on the application of the EIS quality review package as proposed by Lee and Colley (1992), the outcomes reveal opportunities for improving the scope of EIA, analysis of alternatives, prediction of magnitude and the assessment of impact significance. Finally, the development and/or adaptation of a similar tool for the systematic review of the quality of EIA reports is recommended. 展开更多
关键词 environmental Impact Assessment EFFECTIVENESS Electric Energy Transmission systems
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Carbon fluxes and their response to environmental variables in a Dahurian larch forest ecosystem in northeast China 被引量:6
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作者 王辉民 三枝信子 +3 位作者 祖元刚 王文杰 山本晋 近藤裕昭 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第1期1-10,共10页
The Dahurian larch forest in northeast China is important due to its vastness and location within a transitional zone from boreal to temperate and at the southern distribution edge of the vast Siberian larch forest. T... The Dahurian larch forest in northeast China is important due to its vastness and location within a transitional zone from boreal to temperate and at the southern distribution edge of the vast Siberian larch forest. The continuous carbon fluxes were measured from May 2004 to April 2005 in the Dahurian larch forest in Northeast China using an eddy covariance method. The results showed that the ecosystem released carbon in the dormant season from mid-October 2004 to April 2005, while it assimilated CO2 from the atmosphere in the growing season from May to September 2004. The net carbon sequestration reached its peak of 112 g.m^-2.month ^-1 in June 2004 (simplified expression of g (carbon).m^-2.month^-1) and then gradually decreased. Annually, the larch forest was a carbon sink that sequestered carbon of 146 g-m^-2.a^-1 (simplified expression of g (carbon).m^-2.a^-1) during the measurements. The photosynthetic process of the larch forest ecosystem was largely affected by the vapor pressure deficit (VPD) and temperature. Under humid conditions (VPD 〈 1.0 kPa), the gross ecosystem production (GEP) increased with increasing temperature. But the net ecosystem production (NEP) showed almost no change with increasing temperature because the increment of GEP was counterbalanced by that of the ecosystem respiration. Under a dry environment (VPD 〉 1.0 kPa), the GEP decreased with the increasing VPD at a rate of 3.0 μmol.m^-2.s^-1kPa -1 and the ecosystem respiration was also enhanced simultaneously due to the increase of air temperature, which was linearly correlated with the VPD. As a result, the net ecosystem carbon sequestration rapidly decreased with the increasing VPD at a rate of 5.2 μmol.m^-2.s-1.kPa^-1. Under humid conditions (VPD 〈 1.0 kPa), both the GEP and NEP were obviously restricted by the low air temperature but were insensitive to the high temperature because the observed high temperature value comes within the category of the optimum range. 展开更多
关键词 carbon balance eddy covariance method environmental effect larch forest Larix gmelinii
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Study on Environmental Protection during Agricultural Eco-tourism Development in Guangzhou City——From the Perspective of Perfecting Environmental Responsibility System of Tourism Company
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作者 周帮扬 梅章慧 李健全 《Journal of Landscape Research》 2011年第1期60-63,69,共5页
By taking Guangzhou City for example,a series of environmental problems brought by agricultural ecological tourism were analyzed from the perspective of environmental degradation caused by that tourism company failed ... By taking Guangzhou City for example,a series of environmental problems brought by agricultural ecological tourism were analyzed from the perspective of environmental degradation caused by that tourism company failed to take environmental responsibility.Based on economic development and environmental protection,some suggestions on environmental protection were proposed from the perspective of perfecting environmental responsibility of tourism company in order to realize win-win of economic development and environmental protection. 展开更多
关键词 Agricultural ECO-TOURISM environmental pollution environmental RESPONSIBILITY of COMPANY
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Key Environmental Factors Monitoring System of Low-power Greenhouse Based on WSN Technology
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作者 柳军 陶建平 吕晓兰 《Agricultural Science & Technology》 CAS 2016年第2期449-452,共4页
A low-power environmental monitoring system based on WSN technology is proposed to effectively monitor the environmental status and ensure the healthy growth of greenhouse crops in the greenhouse. The system performs ... A low-power environmental monitoring system based on WSN technology is proposed to effectively monitor the environmental status and ensure the healthy growth of greenhouse crops in the greenhouse. The system performs dynamic mon- itoring on the environmental data of temperature, humidity, illumination, soil tempera- ture and humidity of the greenhouse, and it reduces the energy consumption by us- ing solar energy and lithium battery as the power supply mode and dynamic power management algorithm combined with improved routing protocol. Stable and reliable, the system could effectively monitor the key environmental factors in the green- house, making it of certain promotion value. 展开更多
关键词 environmental monitoring GREENHOUSE Wireless sensor network WSN technology Key factor
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Generalized Goal Programming and Its Application in Water Environmental System
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作者 ZHANG Shiying, YANG Baochen, FAN YichangDepartment of Engineering Economics and Systems Engineering,Tianjin University, Tianjin 300072, China 《Systems Science and Systems Engineering》 CSCD 1993年第1期37-45,共9页
This paper presents the concept of generalized goal programming (GGP), the characteristics of the programming model is "designing optimum system". Firstly, based on the synthesis of goal programming and Deno... This paper presents the concept of generalized goal programming (GGP), the characteristics of the programming model is "designing optimum system". Firstly, based on the synthesis of goal programming and Denovo programming, one type of generalized goal programming model is established. In the paper the properties of feasible region is studied. Secondly, GGP is enlarged to the case that fuzzy parameters and fuzzy goal sets exist in the GGP model, the solution methods using fuzzy set theory for GGP with fuzzy parameters are provided. Finally, this approach has been used to analyse a water environmental system in coastal city, thus proving its usefulness. 展开更多
关键词 generalized goal programming (GGP) fuzzy set water environmental system coastal city.
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Design and Application of Environmental Monitoring System for Hypsizygus marmoreus in the Cultivation Room 被引量:1
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作者 张康 田小青 +1 位作者 白楠 朱学军 《Agricultural Science & Technology》 CAS 2016年第12期2889-2892,2895,共5页
Hypsizygus marmoreus has a significant dependence on environment at the mycelium growth stage. ln order to col ect, process and display real-time data of temperature, humidity, CO2 concentration in cultivation room, a... Hypsizygus marmoreus has a significant dependence on environment at the mycelium growth stage. ln order to col ect, process and display real-time data of temperature, humidity, CO2 concentration in cultivation room, along-distance environ-ment monitoring system with multi-technology is designed. The curves of tempera-ture, humidity and CO2 concentration, fitted by the MATLAB data fitting toolbox with the experimental data, reflected the changing trend of environmental factors. The mathematical model of CO2 concentration was established by regression analysis, and the regulation strategy that the ventilation period of half an hour and the venti-lation duration of 5 minutes was put forward. 展开更多
关键词 Hypsizygus marmoreus environmental factors Regulation strategy
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Poverty Reduction,Environmental Protection and Ecosystem Services:A Prospective Theory for Sustainable Development 被引量:9
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作者 ZHEN Nahui FU Bojie +1 位作者 LU Yihe WANG Shuai 《Chinese Geographical Science》 SCIE CSCD 2014年第1期83-92,共10页
Poverty reduction and environmental protection are two global tasks for sustainable development.The study perspective has changed over time,from narrowly focusing on poverty reduction to comprehensively strengthening ... Poverty reduction and environmental protection are two global tasks for sustainable development.The study perspective has changed over time,from narrowly focusing on poverty reduction to comprehensively strengthening human-welfare.We reviewed key references targeting the theoretical content and practical approach relying on poverty,environment protection and ecosystem services.We discussed the contradicting views on the relationship of poverty and environmental degradation,and then illustrated the study progress of a cutting-age topic-ecosystem services which pave a way to address poverty reduction and environmental protection together.At last,we investigated essential factors that affect the development and environmental protection.Considering the evolution of the concept of poverty,we found that the environment has occupied an increasing proportion in the cognizance of poverty.The relationship between poverty and environmental degradation is regional uniqueness.In practical aspect,projects based on the management and valuation assessment of ecosystem services draw researchers′attention all over the world.The appropriate scale,essential economic incentives,morality,law and social equality are key factors affecting individuals′decisions which directly relate to the sustainable development. 展开更多
关键词 POVERTY environmental degradation ecosystem services sustainable development
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Internet based environmental monitoring information system and its application in Yili Prefecture 被引量:7
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作者 Deng Xiang-zheng Liu Ji-yuan +1 位作者 Zhuang Da-fang Zhan Jin-yan 《Journal of Geographical Sciences》 SCIE CSCD 2002年第2期40-47,共8页
With the development of Internet technologies, Internet Based Information System (IBIS) arises with more advantages: Firstly, it is convenient for users to use owing to the introduction of Internet technologies. Secon... With the development of Internet technologies, Internet Based Information System (IBIS) arises with more advantages: Firstly, it is convenient for users to use owing to the introduction of Internet technologies. Secondly, it benefits greatly the data dissemination and data sharing based on Internet. The most important but not the last is that we can establish the information service network supported by its technologies and the facilities of information highway. So, it would be significant to design IBIS to realize the data collection, sharing and dissemination on Internet. There are many factors affecting regional environment. So it is not easy to realize the integrated environmental monitoring. Given this, we designed the Internet based environmental monitoring information system. By the virtue of the Internet based environmental monitoring information system, the management and storage of environmental monitoring data would be easier, which lays the foundation to actualize the environmental monitoring efficiently. 展开更多
关键词 environmental monitoring GIS information system INTERNET Web GIS Yili Prefecture
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Environmental and ecological water requirement of river system: a case study of Haihe-Luanhe river system 被引量:9
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作者 LI Li-juan, ZHENG Hong-xing (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第2期224-230,共7页
In order to reduce the environmental and ecological problems induced by water resources development and utilization, this paper proposes a concept of environmental and ecological water requirement. It is defined as th... In order to reduce the environmental and ecological problems induced by water resources development and utilization, this paper proposes a concept of environmental and ecological water requirement. It is defined as the minimum water amount to be consumed by the natural water bodies to conserve its environmental and ecological functions. Based on the definition, the methods on calculating the amount of environmental and ecological water requirement are determined. In the case study on Haihe-Luanhe river system, the water requirement is divided into three parts, i.e., the basic in-stream flow, water requirement for sediment transfer and water consumption by evaporation of the lakes or everglades. The results of the calculation show that the environmental and ecological water requirement in the river system is about 124×108 m3, including 57×108 m3 for basic in-stream flow, 63×108 m3 for sediment transfer and 4×108 m3 for net evaporation loss of lakes. The total amount of environmental and ecological water requirement accounts for 54% of the amount of runoff (228×108 m3). However, it should be realized that the amount of environmental and ecological water requirement must be more than that we have calculated. According to this result, we consider that the rational utilization rate of the runoff in the river systems must not be more than 40%. Since the current utilization rate of the river system, which is over 80%, has been far beyond the limitation, the problems of environment and ecology are quite serious. It is imperative to control and adjust water development and utilization to eliminate the existing problems and to avoid the potential ecological or environmental crisis. 展开更多
关键词 environmental and ecological water requirement river systems Haihe-Luanhe basins
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Study on Environmental Risk and Economic Benefits of Rotation Systems in Farmland of Erhai Lake Basin 被引量:5
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作者 TANG Qiu-xiang REN Tian-zhi +4 位作者 Wilko Schweers LIU Hong-bin LEI Bao-kun LIN Tao ZHANGGui-long 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第6期1038-1047,共10页
This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. Th... This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. The results showed that incomes, residual nitrogen in soil, and the loss of nitrogen in surface water in rice-garlic system were higher than those in rice-fava bean system. There were positive correlations between the nitrogen loss of farmland, nitrogen inputs, residual nitrogen in soil, and incomes of farmland. Economic benefits and environment benefits are both appropriate, if the area of rice-garlic system would be reduced to 53% and the area of rice-fava bean system increased to 36% of total cropping area in the investigated watershed. Adjustment of planting structure and introduction of reasonable rotation systems is considered an effective measure of controlling agricultural non-point pollution in watersheds of Erhai Lake. 展开更多
关键词 watershed management Erhai Lake FARMLAND crop rotation environmental risk economic benefits
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Catalytic degradation of methylene blue by Fenton like system: model to the environmental reaction 被引量:4
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作者 Sanjay R Thakare 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第2期285-287,共3页
To develop more efficient chemical methods for the demineralization of organic pollutants from water bodies, which one was also mimic to the nature, a degradation of methylene blue by Fe(Ⅲ) and H 2O 2 in the absenc... To develop more efficient chemical methods for the demineralization of organic pollutants from water bodies, which one was also mimic to the nature, a degradation of methylene blue by Fe(Ⅲ) and H 2O 2 in the absence of light instead of Fe(Ⅱ) and H 2O 2 was studied. Results showed that use of Fe (Ⅲ) is more promising than Fe(Ⅱ). The present study reflects that Fenton reaction is more efficient, in the presence of a small amount of salicylic acid is added which is a one of the priority pollutant. 展开更多
关键词 advanced oxidation technology Fenton reaction iron(Ⅲ) catalytic degradation environmental application
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Implementation Framework and Validation of Cluster-Nuclei Based Channel Model Using Environmental Mapping for 6G Communication Systems 被引量:4
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作者 Li Yu Yuxiang Zhang +1 位作者 Jianhua Zhang Zhiqiang Yuan 《China Communications》 SCIE CSCD 2022年第4期1-13,共13页
With the research of the upcoming sixth generation(6 G) systems, new technologies will require wider bandwidth, larger scale antenna arrays and more diverse wireless communication scenarios on the future channel model... With the research of the upcoming sixth generation(6 G) systems, new technologies will require wider bandwidth, larger scale antenna arrays and more diverse wireless communication scenarios on the future channel modeling. Considering channel model is prerequisite for system design and performance evaluation of 6 G technologies, we face a challenging task: how to accurately and efficiently model 6 G channel for various scenarios? This paper tries to answer it. Firstly, the features of cluster-nuclei(CN) and principle of cluster-nuclei based channel model(CNCM) are introduced. Then, a novel modeling framework is proposed to implement CNCM,which consists four steps: propagation environment reconstruction, cluster-nuclei identification, multipath parameters generation, and channel coefficients generation. Three-dimensional environment with material information is utilized to map CN with scatterers in the propagation pathway. CN are identified by geometrical and electric field calculation based on environmental mapping, and multipath components within CN are calculated by statistical characteristics of angle, power and delay domains. Finally, we present a three-level verification structure to investigate the accuracy and complexity of channel modeling comprehensively. Simulation results reveal that CNCM can perform higher accuracy than geometrybased stochastic model while lower complexity compared with ray-tracing model for practical propagation environment. 展开更多
关键词 channel model 6G cluster-nuclei environmental mapping SCATTERER RAY-TRACING geometrybased stochastic model
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A case for systemic environmental analysis of cultured meat 被引量:5
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作者 Carolyn S Mattick Amy E Landis Braden R Allenby 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第2期249-254,共6页
The environmental implications of cultured meat are profound. An anticipatory life cycle assessment of cultured meat published in 2011 suggested it could have a smaller impact than agricultural meat in all categories ... The environmental implications of cultured meat are profound. An anticipatory life cycle assessment of cultured meat published in 2011 suggested it could have a smaller impact than agricultural meat in all categories except energy consumption. As with most technologies, cultured meat will almost certainly be accompanied by unintended consequences as well as unforeseen costs and benefits that accrue disproportionately to different stakeholders. Uncertainty associated with new engineered products cannot be completely eliminated prior to introduction, but ongoing environmental assessments of the technologies as they advance can serve to reduce unforeseen risks. Given the pace at which tissue engineering is advancing, systemic assessments of the technology will be pivotal in mitigating unintended environmental consequences. 展开更多
关键词 cultured meat in vitro meat factory-grown food anticipatory life cycle assessment systemic environmental implications of emerging technologies
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