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Differences between young architects'and non-architects'aesthetic evaluation of buildings
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作者 Katarína Safárová Martin Pírko +2 位作者 Vojtěch Jurík Tomás Pavlica Ondrej Németh 《建筑学研究前沿(英文版)》 CSCD 2019年第2期229-237,共9页
Previous studies showed significant differences between expert architects and laypeople in aesthetic evaluations of buildings.However,studies exploring the aesthetic preferences of architecture students are lacking.Th... Previous studies showed significant differences between expert architects and laypeople in aesthetic evaluations of buildings.However,studies exploring the aesthetic preferences of architecture students are lacking.The present study focused on a population of students and young architects to explore the aesthetic opinion shift within architectural careers.This study was intended to be a conceptual replication of the study of Brown and Gifford(2001)in a Central European context.A total of 109 participants(21-28 years old)evaluated 40 randomized pictures of houses to detect whether non-architecture undergraduates and fresh graduates of architecture would express different aesthetic preferences compared with their peers from the general population.The study also examined whether laypersons can predict the preferences of architects,and vice versa.Results show a trend that is contrary to the original research,that is,young architects and laypeople did not significantly differ in their aesthetic evaluations of the given stimuli.Analyses revealed high prediction ability in young architects and their non-architect peers.Moreover,the existing professional experience of young architects had no influence on the accuracy of their estimations.Findings suggest that the professional shift in architects'expertise is obscured at an early career stage,as revealed in their aesthetic preferences. 展开更多
关键词 ENVIRONMENTAL AESTHETICS AESTHETIC PREFERENCES Building AESTHETICS ENVIRONMENTAL APPERCEPTION Professional opinion shift
Do Political Connections Promote Innovation in Environmentally Polluting Enterprises?
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作者 Jianhua Zhang Xiaoqing Li +1 位作者 Hung-Gay Fung Penghua Qiao 《中国与世界经济:英文版》 2019年第3期76-101,共26页
We use an unbalanced panel data analysis to examine the effect of political connections(PCs)in state-owned enterprises(SOE)and non-SOEs on the innovation of Chinese environmentally polluting enterprises listed on the ... We use an unbalanced panel data analysis to examine the effect of political connections(PCs)in state-owned enterprises(SOE)and non-SOEs on the innovation of Chinese environmentally polluting enterprises listed on the Shanghai and Shenzhen Stock Exchanges from 2007 to 2016.Our sample consists of 792 firms and 4587 firm-year observations.There are several interesting findings.First,SOEs that are politically linked to the central government promote more innovation in general and more environmental innovation than SOEs without these links.Second,privately-owned enterprises(non-SOEs)with PCs promote less environmental innovation than non-SOEs without PCs.Third,environmental regulation does not affect the environmental innovation of SOEs but it drives non-SOEs with PCs to become more environmentally innovative.Our results enable us to better understand how PCs and regulations affect environmental innovation. 展开更多
关键词 ENVIRONMENTAL INNOVATION ENVIRONMENTAL regulation HIGHLY polluting ENTERPRISES POLITICAL connections
News: JES Symposium on Recent Advances in Environmental Sciences, to be held at the 10th National Conference on Environmental Chemistry
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《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第6期327-328,共2页
A special Journal of Environmental Sciences (JES) Symposium,Recent Advances in Environmental Sciences, will be held at the 10th National Conference on Environmental Chemistry(NCEC), in Tianjin, China, on August 15-19,... A special Journal of Environmental Sciences (JES) Symposium,Recent Advances in Environmental Sciences, will be held at the 10th National Conference on Environmental Chemistry(NCEC), in Tianjin, China, on August 15-19, 2019. Submissions of abstracts on all topics of environmental sciences are welcome. 展开更多
关键词 NATIONAL CONFERENCE on ENVIRONMENTAL Chemistry JES SYMPOSIUM on Recent Advances in ENVIRONMENTAL SCIENCES
A model for the evaluation of environmental impact indicators for a sustainable maritime transportation systems
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作者 Lizzette PEREZ LESPIER Suzanna LONG +1 位作者 Tom SHOBERG Steven CORNS 《工程管理前沿:英文版》 2019年第3期368-383,共16页
Maritime shipping is considered the most efficient,low-cost means for transporting large quantities of freight over significant distances.However,this process also causes negative environmental and societal impacts.Th... Maritime shipping is considered the most efficient,low-cost means for transporting large quantities of freight over significant distances.However,this process also causes negative environmental and societal impacts.Therefore,environmental sustainability is a pressing issue for maritime shipping management,given the interest in addressing important issues that affect the safety,security,and air and water quality as part of the efficient movement of freight throughout the coasts and waterways and associated port facilities worldwide.In丒depth studies of maritime transportation systems(MTS)can be used to identify key environmental impact indicators within the transportation system.This paper develops a tool for decision making in complex environments;this tool will quantify and rank preferred environmental impact indicators within a MTS.Such a model will help decision-makers to achieve the goals of improved environmental sustainability.The model will also provide environmental policy丒 makers in the shipping industry with an analytical tool that can evaluate tradeoffs within the system and identify possible alternatives to mitigate detrimental effects on the environment. 展开更多
关键词 ENVIRONMENTAL SUSTAINABILITY MARITIME TRANSPORTATION system ENVIRONMENTAL impact INDICATORS fuzzy
On Environmental Quality Standards and Finding of Liability for Environmental Pollution Torts 预览
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作者 You Mingqing Yi Xin(Translator) 《当代社会科学(英文)》 2019年第5期29-47,共19页
Though bearing technical and legal attributes,environmental quality standards are neither rules nor regulatory documents.With the binding force coming from the legal norms where they are cited,environmental quality st... Though bearing technical and legal attributes,environmental quality standards are neither rules nor regulatory documents.With the binding force coming from the legal norms where they are cited,environmental quality standards are designed and implemented as a yardstick for measuring environmental quality.They also play a role in the functions of goal setting,merit appraisals,inspiration,supervision and accountability in conjunction with the legal norms and administrative plans where they are cited.Characteristically,environmental quality standards adopt sort management in concept,take holistic values and methodologies,establish phased goals and accept the resulting policy choices.These standards are not applicable to determine tort liability caused by environmental pollution from the perspective of legal norms but provide limited evidence for finding the same in the view of factual analysis by delivering scientific support to prove negative effects on the environment.Hence,environmental quality standards do contribute to finding torts,thus making the production of evidence less difficult.Also,they can be used to prove the relevance between torts and damage. 展开更多
关键词 ENVIRONMENTAL quality standards ENVIRONMENTAL POLLUTION LIABILITY FACTS norms
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An integrated method of selecting environmental covariates for predictive soil depth mapping 预览
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作者 LU Yuan-yuan LIU Feng +2 位作者 ZHAO Yu-guo SONG Xiao-dong ZHANG Gan-lin 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第2期301-315,共15页
Environmental covariates are the basis of predictive soil mapping.Their selection determines the performance of soil mapping to a great extent,especially in cases where the number of soil samples is limited but soil s... Environmental covariates are the basis of predictive soil mapping.Their selection determines the performance of soil mapping to a great extent,especially in cases where the number of soil samples is limited but soil spatial heterogeneity is high.In this study,we proposed an integrated method to select environmental covariates for predictive soil depth mapping.First,candidate variables that may influence the development of soil depth were selected based on pedogenetic knowledge.Second,three conventional methods(Pearson correlation analysis(PsCA),generalized additive models(GAMs),and Random Forest(RF))were used to generate optimal combinations of environmental covariates.Finally,three optimal combinations were integrated to produce a final combination based on the importance and occurrence frequency of each environmental covariate.We tested this method for soil depth mapping in the upper reaches of the Heihe River Basin in Northwest China.A total of 129 soil sampling sites were collected using a representative sampling strategy,and RF and support vector machine(SVM)models were used to map soil depth.The results showed that compared to the set of environmental covariates selected by the three conventional selection methods,the set of environmental covariates selected by the proposed method achieved higher mapping accuracy.The combination from the proposed method obtained a root mean square error(RMSE)of 11.88 cm,which was 2.25–7.64 cm lower than the other methods,and an R~2 value of 0.76,which was 0.08–0.26 higher than the other methods.The results suggest that our method can be used as an alternative to the conventional methods for soil depth mapping and may also be effective for mapping other soil properties. 展开更多
关键词 ENVIRONMENTAL COVARIATE selection integrated method PREDICTIVE SOIL MAPPING SOIL depth
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贝加尔地区萨彦山东部Jom-Bolok火山谷湖泊古环境研究
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作者 Alexander SHCHETNIKOV Elena V. BEZRUKOVA 《地理学报:英文版》 SCIE CSCD 2019年第11期1823-1840,共18页
This article describes the lake basins of the Jom-Bolok volcanic region in the East Sayan (the largest manifestation of the Holocene eruptions in Central Asia).The geomorphological position,origins,aspects of the stru... This article describes the lake basins of the Jom-Bolok volcanic region in the East Sayan (the largest manifestation of the Holocene eruptions in Central Asia).The geomorphological position,origins,aspects of the structure and development are reviewed considering its sedimentary filling.The limnic morphogenesis here develops under the conditions of contrasting relief,high energy of neotectonic and exogenous processes.We established that Lake Khara-Nur,formed as a result of lava-damming of the Jom-Bolok river valley,emerged in its present form approximately 6500 years ago.A complex record on the environment and climatic changes,acquired from its sediments,made it possible to determine for the first time in this region the long-term trends in the development of the Middle and Late Holocene mountain geosystems and also the distinction of several paleogeographic stages of the formation of the natural environment.An average geochemical record resolution for the bottom sediments of the lake was made uniquely for the East Siberian lake records and is equal to 35 years,while the palynological record approximates 110 years. 展开更多
关键词 lake MORPHOGENESIS Holocene VOLCANISM lava-dammed LAKES environmental change
Spatial variation and soil nitrogen potential hotspots in a mixed land cover catchment on the Chinese Loess Plateau
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作者 YU Yun-long JIN Zhao +6 位作者 LIN Henry WANG Yun-qiang ZHAO Ya-li CHU Guang-chen ZHANG Jing SONG Yi ZHENG Han 《山地科学学报:英文版》 SCIE CSCD 2019年第6期1353-1366,共14页
Soil nitrogen(N) is critical to ecosystem services and environmental quality. Hotspots of soil N in areas with high soil moisture have been widely studied, however, their spatial distribution and their linkage with so... Soil nitrogen(N) is critical to ecosystem services and environmental quality. Hotspots of soil N in areas with high soil moisture have been widely studied, however, their spatial distribution and their linkage with soil N variation have seldom been examined at a catchment scale in areas with low soil water content. We investigated the spatial variation of soil N and its hotspots in a mixed land cover catchment on the Chinese Loess Plateau and used multiple statistical methods to evaluate the effects of the critical environmental factors on soil N variation and potential hotspots. The results demonstrated that land cover, soil moisture, elevation, plan curvature and flow accumulation were the dominant factors affecting the spatial variation of soil nitrate(NN), while land cover and slope aspect were the most important factors impacting the spatial distribution of soil ammonium(AN) and total nitrogen(TN). In the studied catchment, the forestland, gully land and grassland were found to be the potential hotspots of soil NN, AN and TN accumulation, respectively. We concluded that land cover and slope aspect could be proxies to determine the potential hotspots of soil N at the catchment scale. Overall, land cover was the most important factor that resulted in the spatial variations of soil N. The findings may help us to better understand the environmental factors affecting soil N hotspots and their spatial variation at the catchment scale in terrestrial ecosystems. 展开更多
关键词 Soil BIOGEOCHEMISTRY Spatial heterogeneity MULTIVARIATE statistical analysis Environmental factors LOESS Plateau
News: Environmental scientists receive National Science and Technology Awards
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《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第5期367-368,共2页
China’s major achievements in science and technology were publically recognized and celebrated at a recent National Science and Technology Award Conference, held in Beijing on January 8,2019. The National Preeminent ... China’s major achievements in science and technology were publically recognized and celebrated at a recent National Science and Technology Award Conference, held in Beijing on January 8,2019. The National Preeminent Science and Technology Award,the top award, was presented by President Xi Jinping to two outstanding scientists. 展开更多
关键词 ENVIRONMENTAL scientists RECEIVE NATIONAL SCIENCE and Technology AWARDS
River Chief System (RCS):An experiment on cross-sectoral coordination of watershed governance
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作者 Longfei Wang Jiaxin Tong Yi Li 《环境科学与工程前沿(英文)》 SCIE EI CAS CSCD 2019年第4期1-3,共3页
The trans-regional characteristics of watershed governance produce more problems beyond the capacity of each individual water-related department, leading to the fragmentation of watershed management. The River Chief S... The trans-regional characteristics of watershed governance produce more problems beyond the capacity of each individual water-related department, leading to the fragmentation of watershed management. The River Chief System (RCS) has experienced swift developments over the past decade in China by appointing the local government heads as river chiefs. RCS works efficiently in the short-term due to its superiority in the inclusion of clear responsibility, authority, and multi-sectoral collaboration. However, the characteristics of the authority-based vertical coordination of the hierarchical system remain unchanged, and therefore the problems of organizational logic and the responsibility dilemma still exist. Tasks including perfecting of laws, integrated watershed management, and public participation still need to be completed. RCS reflects the routine and characteristics of the migration of national governance, and as such provides new insights for other developing countries in the design of river management systems. 展开更多
关键词 RIVER CHIEF System WATERSHED GOVERNANCE Cross-sectoral COORDINATION Environmental protection
Coastal Environmental Changes and Management in China in the Context of Global Changes and Human Activities 预览
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作者 Yunfeng ZHANG Yingying CHEN +2 位作者 Xiaobin HUA Shiqing YAN Lili ZOU 《亚洲农业研究:英文版》 2019年第7期24-30,33共8页
Coastal zone is the complex area with intense sea-land interaction. There are various types, complex environments and developed economy in coastal area of China. Under the influence of global change and human activiti... Coastal zone is the complex area with intense sea-land interaction. There are various types, complex environments and developed economy in coastal area of China. Under the influence of global change and human activities, the ecosystem of coastal zone is vulnerable and has sensitive response to environment changes. The environmental problems of sea-level rising have attached close attention by countries all over the world. As far as regions concerned, relative sea-level rising is more important than theoretical sea-level rising. The relative sea-level rising has resulted in series of environment disasters in coastal area of China, such as coastal erosion, seawater invasion, and floods in coastal lowlands, etc. The flux of sediments transported by rivers into sea is the main material source of marine pollution. The human activities are controlling factors of variations in river sediment loads. Under the influence of high strength development in the upstream region, the results are that the reduction of seagoing sediments in main rivers of China, and damage of coastal material balance. Land-based pollution is the main source of marine pollution. With rapid economic development in China s eastern coastal, pollutants flux into sea increase gradually. The results are that the environmental quality and seawater quality of marine have being deteriorated and pollution is serious increasingly. To meet the land demand of industrialization and urbanization, the sea reclamation has become an effective means to alleviate the contradiction between human and land in coastal area of China. This leads to large-scale reduction of coastal wetland area, and the heavy losses of ecological service value of coastal wetland. To face the environmental changes in coastal area of China and solve the contradiction among population, resources, environment, development, it is required to set up the system concept of man-land-sea relationship, so as to achieve sustainable development. The feasible measures include improving coastal management s 展开更多
关键词 Costal areas ENVIRONMENTAL changes Human ACTIVITIES Integrated management
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Progress on the development of DNA-mediated metal nanomaterials for environmental and biological analysis
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作者 Jingtai Fu Zhuomin Zhang Gongke Li 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期285-291,共7页
Nowadays, DNA-mediated metal nanomaterials have received more and more attention due to their distinctive properties of easy synthesis, high stability and good biocompatibility. As a kind of efficient template to medi... Nowadays, DNA-mediated metal nanomaterials have received more and more attention due to their distinctive properties of easy synthesis, high stability and good biocompatibility. As a kind of efficient template to mediate the precise synthesis of metal nanomaterials, DNA can not only increase their recognition and biocompatibility, but also precisely control their morphology, structure and further analytical performance. DNA-mediated metal nanomaterials as ultrasensitive and selective probes have unique advantages for in situ rapid analysis of targets in complex samples. Herein, we reviewed the recent progress on synthesis strategies, morphologies, specific properties of DNA-mediated metal nanomaterials including nanoparticles and nanoclusters. Moreover, the applications of DNA-mediated metal nanomaterials to environmental and biological analysis were also summarized. Finally, the developing prospect of DNA-mediated metal nanomaterials in analytical chemistry was discussed and proposed. 展开更多
关键词 DNA-mediated METAL NANOMATERIALS METAL nanoparticles METAL nanoclusters ENVIRONMENTAL ANALYSIS Biological ANALYSIS
Soil Microbiomes-a Promising Strategy for Contaminated Soil Remediation: A Review
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作者 TENG Ying CHEN Wei 《土壤圈:英文版》 SCIE CAS CSCD 2019年第3期283-297,共15页
Bioremediation is a process mediated by microorganisms and represents a sustainable and eco-friendly way to degrade and detoxify environmental contaminants. Soil microbiomes clearly become a key component of bioremedi... Bioremediation is a process mediated by microorganisms and represents a sustainable and eco-friendly way to degrade and detoxify environmental contaminants. Soil microbiomes clearly become a key component of bioremediation as they are more stable and effcient than pure cultures, being recognized as one of the scientific frontiers of the soil environmental science and technology fields. Recently,many advancements have been made regarding the investigation of remediation mechanisms by soil microbiomes and the interactions inside them. This has greatly expanded our ability to characterize the remediating function of soil microbiomes and identify the factors that influence their effciency for remediation. Here, we suggest that soil microbiomes are a promising strategy for soil remediation.Research is now needed to identify how we can manipulate and manage soil microbiomes to improve remediation effciency and increase soil fertility at the same time. Therefore, this review aims to emphasize the importance of soil microbiomes in bioremediation and promote further development of this strategy into a widely accepted technique. 展开更多
关键词 BIOREMEDIATION CONTAMINANT degradative mechanism environmental pollution MICROBIAL consortia MICROORGANISMS REMEDIATION effciency
Reporting on Land as Natural Capital by Gold Mining Houses in South Africa 预览
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作者 Anet Smit TK Bungane 《管理研究:英文版》 2019年第4期300-314,共15页
Motivated by the increasing popularity and advocating for integrated reporting by companies on their operations,the aim of this paper is to determine the disclosure levels on land by mining houses in South Africa in t... Motivated by the increasing popularity and advocating for integrated reporting by companies on their operations,the aim of this paper is to determine the disclosure levels on land by mining houses in South Africa in their integrated reports.Developing countries,such as South Africa should ensure sustainability of their natural resources in their endeavour of growing their economies.The mining sector in South Africa is a huge contributor to the economy,but also has a significant impact on land conservation.The complexity of mining activities and impacts thereof make it challenging for organisations to disclose information on land.This paper is descriptive by design;it contains a literature review,followed by a content analysis of the mining houses integrated reports by using a checklist.The checklist was based on recommendations by the Global Reporting Initiative(GRI)guidelines as to what the content of the integrated report on land should be.Fourteen mining houses operating in South Africa and registered on the Johannesburg Stock Exchange(JSE)were identified and analysed for this study.The findings of the paper display low levels of overall disclosure on land by the South African mining companies.However,there were high levels of disclosure for EN11,EN12,and MM1 sector-specific supplement in the integrated reports.Low levels of disclosure by the mining companies were evident in MM2 the sector-specific recommendations as well as the physical and monetary information related to MM2. 展开更多
关键词 NATURAL CAPITAL environmental impact LAND MINING Global REPORTING INITIATIVE 4 integrated REPORTING
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Application Progress of Headspace Gas Chromatography in Analytical Chemistry 预览
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作者 Fengfeng ZHANG Yu ZHANG Xiaoxiang QIU 《亚洲农业研究:英文版》 2019年第5期58-60,66共4页
This paper briefly expounds the basic principle and classification of headspace gas chromatography,summarizes its application in food analysis,environmental analysis and medical analysis,and forecasts the application ... This paper briefly expounds the basic principle and classification of headspace gas chromatography,summarizes its application in food analysis,environmental analysis and medical analysis,and forecasts the application prospect of headspace gas chromatography in analytical chemistry in the future. 展开更多
关键词 HEADSPACE gas CHROMATOGRAPHY FOOD ANALYSIS Environmental ANALYSIS Medical ANALYSIS APPLICATION PROGRESS
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Science and Technology Associations and Social Governance of Britain in the Middle and Late 19^th Century 预览
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作者 ZHAO Wenyuan 《景观研究:英文版》 2019年第1期108-110,113共4页
Civil science and technology associations have been widely springing up everywhere in Britain,especially the new industrial towns in the eighteenth and nineteenth centuries.Associations held various academic activitie... Civil science and technology associations have been widely springing up everywhere in Britain,especially the new industrial towns in the eighteenth and nineteenth centuries.Associations held various academic activities,organized and funded scientific research,which played an important role in promoting the progress of science and technology and the development of industrial society.Based on case study on British Association for the Advancement of Science and Manchester Literary and Philosophical Society by academic circles at home and abroad,development situation of British science and technology associations in the middle and late 19^th century is summarized,and a series of activities of associations participating in industrial and agricultural development and environmental health reform are systematically sorted out,while the promoting role of science and technology associations in the social development of Britain in the 19th century is explored. 展开更多
关键词 BRITAIN Science and technology societies Environmental GOVERNANCE Public health
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Special topic on organic and perovskite photovoltaics
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作者 Hongzheng Chen Yongfang Li Alex K.-Y. Jen 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第7期797-799,共3页
Photovoltaics, as a green technology for converting solar energy into electricity, have shown great promise to address the energy and environmental challenges for the sustainability of human society. In recent years, ... Photovoltaics, as a green technology for converting solar energy into electricity, have shown great promise to address the energy and environmental challenges for the sustainability of human society. In recent years, two types of photovoltaics, consisting of organic semiconductors or perovskites as light absorbers, have experienced a rapid development. The development of organic solar cells (OSC) can be dated back to 1986, since the discovery of a bi layer OSC by Di. C. W. Tang. Nowadays, OSCs made with polymer donors and small molecule acceptors have surpassed power conversion efficiencies (PCEs) of 16% for single-junction and 17% for tandem devices, through integrated innovative efforts on materials, interfaces, and device architectures. 展开更多
关键词 PEROVSKITE photovoltaics ELECTRICITY ENVIRONMENTAL CHALLENGES
Study on Multi-variables Decoupled Fuzzy Controller for Confined Pig House in Northern China 预览
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作者 Shen Wei-zheng Zhang Si-yuan +4 位作者 Yin Yan-ling Zhang Yu Wang Run-tao Yu Hai-jiao Nagi Eltieb 《东北农业大学学报:英文版》 CAS 2019年第1期73-85,共13页
In winter, the confined pig house of northern China is severe. The environment variables are nonlinear, time-varying and coupled, which seriously affect the health of pigs and the qualities of the meat. In order to so... In winter, the confined pig house of northern China is severe. The environment variables are nonlinear, time-varying and coupled, which seriously affect the health of pigs and the qualities of the meat. In order to solve the problem multi-variables coupling, a multi-variables decoupled fuzzy logic control method was proposed. Two fuzzy logic controllers were designed based on fuzzy logic theory. The fans, heaters and humidifiers were used to control temperature, humidity and ammonia. The reductions of temperature and humidity caused by ventilating were compensated by heaters and humidifiers respectively which realized the multivariables decoupling. The proposed methods were validated through theoretical, experimental and simulation analysis. The results suggested that the methods were able to regulate the confined pig house environment effectively. In addition, comparing to the manual regulation, the proposed methods could reduce 19% power consumption as well. 展开更多
关键词 PIG house environment fuzzy CONTROL variable DECOUPLING environmental CONTROL
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Leaching ion adsorption rare earth by aluminum sulfate for increasing efficiency and lowering the environmental impact
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作者 Lifen Yang Cuicui Li +6 位作者 Dashan Wang Fengyang Li Yanzhu Liu Xuezhen Zhou Mingbiao Liu Xiufeng Wang Yongxiu Li 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第4期429-436,共8页
The leaching efficiency(LE) of ion adsorption rare earth(IARE) by the sulfate and chloride of ammonium,magnesium and aluminum were comparatively determined using column leaching method. It is found that at equal equiv... The leaching efficiency(LE) of ion adsorption rare earth(IARE) by the sulfate and chloride of ammonium,magnesium and aluminum were comparatively determined using column leaching method. It is found that at equal equivalent concentration of cation, the LE of IARE by aluminum sulfate is the highest, and the zeta potential of clay mineral particles in the tailing is near to zero, which means a lower risk of landslide and pollutant emission. Furthermore, the optimum concentration of aluminum sulfate is determined to be0.02 mol/L, which is much lower than that of ammonium sulfate and magnesium sulfate. To reduce the production cost and environmental impact, we proposed a multi-stage leaching process, which was firstly leaching with ammonium sulfate and then with aluminum sulfate, following by water washing and lime neutralizing. With the ratio of ammonium sulfate to aluminum sulfate varying from 1:0 to 0.5:0.5, the residual ammonium in tailing decreases from 11.2% to 0.6%, however, the LE of RE shows an optimum value at 0.8:0.2. By neutralizing the pH of tailing with lime water to over 6, the ion concentration in water rinsing solution can meet the requirement for water discharge. At the same time, the zeta potential of clay particles is found to be around-5 mV, means a relatively lower risk of landslide. These facts indicate that the LE of IARE can be increased and the danger caused by tailings landslides and pollutant emissions can be reduced by replacing ammonium sulfate with aluminum sulfate as leaching reagent. 展开更多
关键词 Ion adsorption rare earth Aluminium SULFATE LEACHING EFFICIENCY Environmental protection
“土坯”墙之营造 预览
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作者 王宝珍 《建筑技艺》 2019年第2期108-113,共6页
通过归纳总结不同"土坯"墙的建造方式以及"土坯"墙的维护方法,以期对低技、低造价环保建造、乡村建设等提供参考与助益,并对建构等设计思想的理解提供启发。
关键词 土墙 低技 低造价 环保 建构 乡建
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