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Characteristics and fate behavior of environmentally persistent free radicals in atmospheric particulate matter
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作者 WANG Xueying CUI Long +2 位作者 XUE Yonggang HO Kinfai HUANG Yu 《地球环境学报》 CSCD 2024年第4期596-611,共16页
Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ... Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ability of particulate matter allows EPFRs to migrate over long-distance transport,thereby impacting the quality of the local atmospheric environment.Additionally,EPFRs can also adhere to atmospheric particles and interact with typical gaseous pollutants to affect atmospheric chemical reactions.EPFRs can produce some reactive organic species,promoting oxidative stress in the human body,damaging biological macromolecules and ultimately affecting the organism health.EPFRs are considered as a novel type of pollutant that affects human health.Despite their significance,there are few literatures available on the characteristics and fate behaviors of EPFRs up to date.Therefore,supplemental reviews are crucial for providing comprehensive understanding of EPFRs.Materials and methods This review summarizes the characteristics of EPFRs in particulate matter,outlines the generation mechanism and influencing factors of EPFRs,and the impacts of EPFRs on environmental quality and organism health.Results The content of EPFRs in particulate matter ranges from 1017 to 1020 spins∙g−1.Due to the strong mobility of atmospheric particulate matter,the long-term exposure to high levels of EPFRs may aggravate the impact of particulate matter on human health.The interaction between EPFRs and typical gaseous pollutants can alter their fate and influence atmospheric chemical reactions.EPFRs are mainly produced by transition metal elements and substituted aromatic hydrocarbons through electron transfer.Additionally,the chemical bond rupture of organic substances through heat treatment or ultraviolet radiation can also produce EPFRs,and heterogeneous reactions are capable producing them as well.The production of EPFRs is not only influenced by transition metal elements and precursors,but also by various environmental factors such as oxygen,temperature,light radiation,and relative humidity.Discussion EPFRs in atmospheric particulates matters are usually rich in fine particulates with obvious seasonal and regional variations.They can easily enter the human respiratory tract and lungs with inhalable particulates,thereby increasing the risk of exposure.Additionally,EPFRs in atmospheric particulates can interact with some typical gaseous pollutants,impacting the life and fate of EPFRs in the atmosphere,and alter atmospheric chemical reactions.Traditionally,EPFRs are generated by transition metal elements and substituted aromatic hydrocarbons undergoing electron transfer in the post-flame and cool-zone regions of combustion systems and other thermal processes to remove HCl,H_(2)O or CO groups,ultimately produce semiquinones,phenoxyls,and cyclopentadienyls.Recent studies have indicated that EPFRs can also be generated under the conditions of without transition metal elemental.Organics can also produce EPFRs through chemical bond rupture during heat treatment or light radiation conditions,as well as through some heterogeneous reactions and photochemical secondary generation of EPFRs.The presence or absence of oxygen has different effects on the type and yield of EPFRs.The concentration,type,and crystal type of transition metal elements will affect the type,content,and atmospheric lifetime of EPFRs.It is generally believed that the impact of transition metal element types on EPFRs is related to the oxidation-reduction potential.The combustion temperature or heat treatment process significantly affects the type and amount of EPFRs.Factors such as precursor loading content,pH conditions,light radiation and relative humidity also influence the generation of EPFRs.EPFRs can interact with pollutants in the environment during their migration and transformation process in environmental medium.This process accelerates the degradation of pollutants and plays a crucial role in the migration and transformation of organic pollutants in environmental media.The reaction process of EPFRs may lead to the production of reactive oxygen species(ROS)such as∙OH,which can induce oxidative stress,inflammation and immune response to biological lung cells and tissues,leading to chronic respiratory and cardiopulmonary dysfunction,cardiovascular damage and neurotoxic effects,ultimately impacting the health of organisms.Conclusions The interaction mechanism between EPFRs in particulate matter and gaseous pollutants remains unclear.Furthermore,research on the generation mechanism of EPFRs without the participation of transition metals is not comprehensive,and the detection of EPFRs is limited to simple qualitative categories and lack accurate qualitative analysis.Recommendations and perspectives Further research should be conducted on the generation mechanism,measurement techniques,migration pathways,and transformation process of EPFRs.It is also important to explore the interaction between EPFRs in atmospheric particulate matter and typical gaseous pollutants. 展开更多
关键词 particulate matter(PM) environmentally persistent free radicals(EPFRs) formation mechanism influencing factors
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铁矿烧结烟气中SO_2的排放规律 被引量:25
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作者 潘建 朱德庆 +2 位作者 崔瑜 陈栋 周仙霖 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第6期1495-1500,共6页
从烧结过程燃料用量、混合料水分、烧结矿碱度及混合料含硫量研究烧结工艺参数对烧结烟气中SO2排放的影响,发现烧结过程SO2的排放不受烧结工艺参数及原料含硫变化的影响,在烧结终点前始终存在一个排放浓度峰值区间,揭示烧结烟气SO2排放... 从烧结过程燃料用量、混合料水分、烧结矿碱度及混合料含硫量研究烧结工艺参数对烧结烟气中SO2排放的影响,发现烧结过程SO2的排放不受烧结工艺参数及原料含硫变化的影响,在烧结终点前始终存在一个排放浓度峰值区间,揭示烧结烟气SO2排放的自持性规律是由于烧结料层有选择性吸附SO2作用所导致,SO2的排放遵循硫化物、硫酸盐热分解生成—料层吸附—再分解—解吸的迁移及循环富集排放机理。 展开更多
关键词 铁矿烧结 减量排放 烟气脱硫 自持性
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远程教育如何培养学习兴趣 被引量:1
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作者 范明天 《中国成人教育》 北大核心 2004年第11期71-72,共2页
一、人本主义心理学和自持性链式反应。人本主义心理学创始人马斯洛通过研究那些优秀的人物.认为他们都是自我实现的人。在他们得到自我实现的过程当中,都要经历一个特殊的一种体验,称之为高峰体验。在某一时候,一个人突然得到了他... 一、人本主义心理学和自持性链式反应。人本主义心理学创始人马斯洛通过研究那些优秀的人物.认为他们都是自我实现的人。在他们得到自我实现的过程当中,都要经历一个特殊的一种体验,称之为高峰体验。在某一时候,一个人突然得到了他从来没有想到过的一种感受,这种感受让他自己认识到自己的潜能,觉得他有能力去做任何他想做的事情,凡是成就一番事业的人必然要经历这样一个过程。很多人都给他描述这样的经历,这样的过程有时是非常短暂的,但在他的一生当中却起很大的作用。这样一种高峰体验,对于他能不能实现真正的自我,是起决定性作用的。 展开更多
关键词 远程教育 学习兴趣 人本主义心理学 自持性链式反应 自主学习 创造思维 教学资源
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Study on Disturbances and Its Effects on Nature Reserves
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作者 Zhang Linying Zhou Yongzhang Xu Songjun 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第3期11-20,共10页
As a widespread natural phenomenon, disturbances are considered a discrete event occurring in a natural ecosystem within various spatial and temporal scales. The present paper discusses the types of disturbances and t... As a widespread natural phenomenon, disturbances are considered a discrete event occurring in a natural ecosystem within various spatial and temporal scales. The present paper discusses the types of disturbances and their influence on the ecologic system in nature reserves. It is shown that nature reserves are facing a great challenge dealing with these disturbances. A rational control for disturbances should be improved in order to promote the healthy development of nature reserves this could be done by enhancing the publicity and training of environment protection, coupling management with communities around and other nature reserves, effective management methods, rational planning, and supporting nature servers. 展开更多
关键词 DISTURBANCE nature reserve ecologic system sustainable development
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Celebration’s Urban Environment, Sustainable by the Joy of Living
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作者 Adilson Costa Macedo 《Journal of Civil Engineering and Architecture》 2018年第6期416-427,共12页
Besides arguments like fighting against dispersed urbanization, improving economies of infrastructure and preserving natural resources, another measure to sustainability is the delight of people in staying together wi... Besides arguments like fighting against dispersed urbanization, improving economies of infrastructure and preserving natural resources, another measure to sustainability is the delight of people in staying together with others sharing a well-designed urban landscape. Analyzing the Celebration’s urban setting is highlighted how some design firms are turning to reclaim the types of urbanism and traditional American architecture, representing the wish for reinforcing the daily vicinity relationships. As a matter of sustainability, it mentioned aspects of vehicular accessibility and the population density which is higher in Celebration than that in other suburban towns in USA. Attention is given both to the management of natural landscape and the role of the entrepreneur to construct a town in a so fragile soil. The relationship between community and sustainability is highlighted, leading to the idea of building spaces to become places, capable to convey the feeling of joy of living. 展开更多
关键词 Smart growth new urbanism sustainable design city architecture urban design
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Ecology, Environment, Sustainability: The Development of the Environmental Movement in Israel
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作者 Benny Furst 《Cultural and Religious Studies》 2016年第4期238-253,共16页
The article surveys the development of the environmental movement in Israel from the establishment of the state through the present day. Based on trends and transformations in the institutional planning system, it app... The article surveys the development of the environmental movement in Israel from the establishment of the state through the present day. Based on trends and transformations in the institutional planning system, it appears that activism by environmental movement organizations in Israel can be divided into three sub-periods: the establishment period, marked by the Sharon Plan, the founding of the Society for the Protection of Nature in Israel and MALRAZ--Council for the Prevention of Noise and Air Pollution in Israel, and the enactment of the Kanovitch Law and the National Parks and Nature Reserves Law (1963). The next phase of institutionalization is characterized by the establishment of designated institutional bodies--the Nature Reserves Authority, the National Parks Authority and the Environmental Protection Service, and their integration into the national planning system. The institutionalization period concludes with the establishment of the Ministry of the Environment (1989) and the transition to the third period, sustainability. Prominent during this period is a trend toward multidimensional proactive environmental planning and policymaking, reaching across many areas and including extensive regulation As far as environmental organizations are concerned, these three periods comprised a framework of cultural action in which they developed, acted and shaped environmental discourse and practice in Israel. Based on other studies, the article offers a model that illustrates the development of the environmental movement while emphasizing the interaction between individual actors, local organizing and national organizations. Finally, some characteristics and insights regarding activism by environmental organizations in Israel are suggested. 展开更多
关键词 ENVIRONMENTALISM environmental campaigns environmental movement organizations (EMO's) SUSTAINABILITY
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Action Recognition from a Different View 被引量:1
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作者 陈昌红 干宗良 《China Communications》 SCIE CSCD 2013年第12期139-148,共10页
In this paper,we propose a novel approach to recognise human activities from a different view.Although appearance-based recognition methods have been shown to be unsuitable for action recognition for varying views,the... In this paper,we propose a novel approach to recognise human activities from a different view.Although appearance-based recognition methods have been shown to be unsuitable for action recognition for varying views,there must be some regularity among the same action sequences of different views.Selfsimilarity matrices appear to be relative stable across views.However,the ability to effectively realise this stability is a problem.In this paper,we extract the shape-flow descriptor as the low-level feature and then choose the same number of key frames from the action sequences.Self-similarity matrices are obtained by computing the similarity between any pair of the key frames.The diagonal features of the similarity matrices are extracted as the highlevel feature representation of the action sequence and Support Vector Machines(SVM) is employed for classification.We test our approach on the IXMAS multi-view data set.The proposed approach is simple but effective when compared with other algorithms. 展开更多
关键词 action recognition different view shape-flow descriptor self-similarity matrix diagonal feature
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Classification of wintertime large-scale tilted ridges over the Eurasian continent and their influences on surface air temperature 被引量:1
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作者 Da-Wei LIN Cholaw BUEH Zuo-Wei XIE 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第5期404-411,共8页
This study investigates the major patterns of large-scale tilted ridges(LSTRS)over the Eurasian continent and their connections with large-scale surface air temperature during boreal winter.A total number of 134 LSTR ... This study investigates the major patterns of large-scale tilted ridges(LSTRS)over the Eurasian continent and their connections with large-scale surface air temperature during boreal winter.A total number of 134 LSTR events with zonal extent exceeding 90°of longitude on the peak day are identified.Using self-organizing map(SOM),the LSTRs are classified into five clusters that are characterized by different spatial distributions and orientations.The leading two clusters are closely associated with extensive and persistent cold events over different places.Considering the first cluster,LSTRs extend from the Ural Mountains to Northeast Asia and are favorable for the amplification and southeastward extension of the Siberian high.Therefore,this cluster is closely associated with the occurrence of extensive and persistent cold events in china.In comparison with the first cluster,the LSTRs of second group are situated to the west,with starting points from the Kola Peninsula,and cause extensive and persistent cold events over Eastern Europe,central Asia,and central Siberia.The results suggest that the vertical coupling between LSTRs and the corresponding anomalous sea level pressure is crucial for the persistent cold temperature events associated with the leading two SOM clusters. 展开更多
关键词 Large-scale tilted ridges self-organizing map extensive and persistent cold event Siberian high
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Adaptive associative classification with emerging frequent patterns
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作者 Wang Xiaofeng Zhang Dapeng Shi Zhongzhi 《High Technology Letters》 EI CAS 2012年第1期38-44,共7页
In this paper, we propose an enhanced associative classification method by integrating the dynamic property in the process of associative classification. In the proposed method, we employ a support vector machine(SVM... In this paper, we propose an enhanced associative classification method by integrating the dynamic property in the process of associative classification. In the proposed method, we employ a support vector machine(SVM) based method to refine the discovered emerging ~equent patterns for classification rule extension for class label prediction. The empirical study shows that our method can be used to classify increasing resources efficiently and effectively. 展开更多
关键词 associative classification RULE frequent pattern mining emerging frequent pattern supportvector machine (SVM)
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Sustainability of Local Food Supply Chain in the New Theory Agriculture
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作者 Chutchai Suksa-ard Morrakot Raweewan 《Journal of Modern Accounting and Auditing》 2011年第7期749-757,共9页
World food production and its economic have rapidly grown over a decade; and number of supply chain management research has also increased in this field. However, this development relates to natural resources depletio... World food production and its economic have rapidly grown over a decade; and number of supply chain management research has also increased in this field. However, this development relates to natural resources depletion and deterioration of quality of life in rural population, especially in smallholder farmers. Thailand has practiced the New Theory Agriculture (NTA), one application aligned with sufficient economy. This theory not only remedies damaged natural resources but also helps smallholder farmers to improve quality of life; and it is analogous to local food supply chain theory, that is well-known in western countries. However, NTA has not been measured its sustainability. Following sustainable food criteria and sustainable agriculture criteria, this paper uses an Indicator of Sustainable Agricultural Practice (ISAP) to measure sustainability at farm level of small rural community's network called Inpaeng, a case study that has practiced NTA. The result of assessment in this case implies that NTA yields sustainability to local food supply chain more than monocrop system. 展开更多
关键词 SUSTAINABILITY NTA food supply chains supply chain management
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Measuring Contribution of BIM (Building Information Modeling) to the Construction Sustainability Goals
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作者 Arjun R. Pandey Farzad Shahbodaghlou 《Journal of Civil Engineering and Architecture》 2016年第3期379-384,共6页
"BIM (building information modeling)" and "sustainability" are two frequently used words in construction and academia today. BIM is a design-oriented tool, which generates a virtual three-dimensional model of a ... "BIM (building information modeling)" and "sustainability" are two frequently used words in construction and academia today. BIM is a design-oriented tool, which generates a virtual three-dimensional model of a project. Sustainability refers to prudent use of earth's natural resources, and construction sustainability is the application of this principle to building activities. Societies in general and the construction industry in particular--one of the largest in terms of natural resources consumed and waste produced--place high hopes on BIM and the principles of sustainability to reduce consumption and waste and to increase industry productivity. BIM's capabilities and limitations, currently more focused on model creation and energy simulations, are not well understood as they relate to construction sustainability and its goals. No method yet exists to evaluate BIM's contribution comprehensively to construction sustainability goals. This study presents a construction sustainability goals contribution matrix for BIM. The matrix indicates that this contribution may be more limited than it is commonly thought. 展开更多
关键词 BIM sustainability principles construction sustainability goals building ecology
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Adoption of Participatory Forest Management System for Sustainability in Nigeria
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作者 Samuel Iwah Udofia Opeyemi Olajide Egor Bassey Etigale 《Journal of Life Sciences》 2013年第8期901-906,共6页
Forest is a composite renewable natural resource of multiple values to mankind. Over the years in Nigeria, government has been the sole player in the management of forest resources at the exclusion of the neighbouring... Forest is a composite renewable natural resource of multiple values to mankind. Over the years in Nigeria, government has been the sole player in the management of forest resources at the exclusion of the neighbouring forest-dependent communities to forest estates. The consequences of the monopolistic management are widespread illegal and destructive lumbering, degradation, deforestation and varying ecological disasters. This paper, therefore, discusses strategies that could facilitate and foster participatory sustainable forest management which include formulation of people-orientated forest policies and laws, creation of public awareness, stakeholders' consultation, training and capacity building, provision of incentives and creation of market channels for forest products. The aim is to underscore the potency of people-based forest management system, which considers the peoples' interest and welfare while ensuring effective conservation of forest resources. The method adopted is a review and appraisal of the prevailing situations. It is recommended that mass mobilization for participation in sustainable forest resources management and creation of enabling environment for organized private-sector involvement in forest resources activities could engender rapid development in forestry sub-sector of Nigerian economy. 展开更多
关键词 Forest resources sustainable management PARTICIPATORY Nigeria.
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Extinction and persistence of a nonautonomous stochastic food-chain system with impulsive perturbations 被引量:1
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作者 Baodan Tian Shouming Zhong Zhijun Liu 《International Journal of Biomathematics》 2016年第5期217-242,共26页
In this paper, a nonautonomous stochastic food-chain system with functional response and impulsive perturbations is studied. By using Ito's formula, exponential martingale inequality, differential inequality and othe... In this paper, a nonautonomous stochastic food-chain system with functional response and impulsive perturbations is studied. By using Ito's formula, exponential martingale inequality, differential inequality and other mathematical skills, some sufficient conditions for the extinction, nonpersistence in the mean, persistence in the mean, and stochastic permanence of the system are established. Furthermore, some asymptotic properties of the solutions are also investigated. Finally, a series of numerical examples are presented to support the theoretical results, and effects of different intensities of white noises perturbations and impulsive effects are discussed by the simu|ations. 展开更多
关键词 Food-chain system functional response stochastic perturbations impulsive effects EXTINCTION stochastic permanence.
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UNIFORM PERSISTENCE AND GLOBAL ATTRACTIVITY FOR NONAUTONOMOUS COMPETITIVE SYSTEMS WITH DISPERSION 被引量:7
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作者 SONGXinyu CHENLansun 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2002年第3期307-314,共8页
In this paper, we consider a nonautonomous competitive model with dispersion and a finite number of discrete delays. The system, which consists of two Lotka-Volterra patches, has two competitors: one can disperse betw... In this paper, we consider a nonautonomous competitive model with dispersion and a finite number of discrete delays. The system, which consists of two Lotka-Volterra patches, has two competitors: one can disperse between the two patches, but the other is confined to one patch and cannot disperse. Our purpose is to demonstrate that the dispersion rates have no effect on the uniform persistence of the solutions of the system. Furthermore, we establish the conditions under which the system admits a positive periodic solution which attracts all solutions. 展开更多
关键词 Uniform persistence global attractivity dispersion.
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Permanence and extinction for a nonautonomous schistosomiasis model with saturation incidence rate
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作者 Dehui Xie Xiangyu Zhang +1 位作者 Shuixian Yan Shujing Gao 《International Journal of Biomathematics》 2015年第2期117-133,共17页
In the real world, quite a few infectious diseases like schistosomiasis spread seasonally. In this paper, a nonautonomous schistosomiasis system is established, in which the saturation incidence rate and the coefficie... In the real world, quite a few infectious diseases like schistosomiasis spread seasonally. In this paper, a nonautonomous schistosomiasis system is established, in which the saturation incidence rate and the coefficients varying with time are taken into account. The long-time behavior of the model is studied. Under quite weak assumptions, sufficient conditions for the permanence and extinction of infectious population of disease are obtained. Finally, numerical simulations illustrate the validity of our results. 展开更多
关键词 Schistosomiasis model seasonal variability EXTINCTION permanence.
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