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701.
17β-Estradiol (E2) is an endocrine disrupting chemical of harm to both animals and human beings at a low concentration level (ng/L). It cannot be completely removed by wastewater treatments, and is often detected in both environment and drinking waters. The purpose of this feasibility study, towards environmental engineering in the field of water analysis and treatment, was to remove E2 by extraction using non-imprinted polymer (NIP) submicron particles. Experimental results showed that 0.5 mg/L of E2 could be completely extracted by adding 10 mg of NIP particles directly into 10 mL of water. However, the extraction efficiency decreased to 64% for 100 mL of water. prefilling the NIP particles inside a membrane filter showed a potential for water treatment of a large volume, requiring no effort to distribute the particles uniformly in the water. High extraction efficiency (80 ± 10)% for E2 was achieved for 100 mL of water. A total mass of 0.29 mg E2 was extracted from 1000 mL of water containing 0.8 mg/L E2 (by using only 10 mg of NIP particles). Both efficiency and mass capacity can be increased, by scaling up the amount of NIP particles, towards environmental engineering applications.  相似文献   
702.
17β-Estradiol (E2) is an endocrine disrupting chemical of harm to both animals and human beings at a low concentration level (ng/L).It cannot be completely removed by wastewater treatments,and is often detected in both environment and drinking waters.The purpose of this feasibility study,towards environmental engineering in the field of water analysis and treatment,was to remove E2 by extraction using non-imprinted polymer (NIP) submicron particles.Experimental results showed that 0.5 mg/L of E2 could be completely extracted by adding 10 mg of NIP particles directly into 10 mL of water.However,the extraction efficiency decreased to 64% for 100 mL of water.prefilling the NIP particles inside a membrane filter showed a potential for water treatment of a large volume,requiring no effort to distribute the particles uniformly in the water.High extraction efficiency (80±10)% for E2 was achieved for 100 mL of water.A total mass of 0.29 mg E2 was extracted from 1000 mL of water containing 0.8 mg/L E2 (by using only 10 mg of NIP particles).Both efficiency and mass capacity can be increased,by scaling up the amount of NIP particles,towards environmental engineering applications.  相似文献   
703.
Leidner, Andrew J., M. Edward Rister, Ronald D. Lacewell, and Allen W. Sturdivant, 2011. The Water Market for the Middle and Lower Portions of the Texas Rio Grande Basin. Journal of the American Water Resources Association (JAWRA) 47(3):597‐610. DOI: 10.1111/j.1752‐1688.2011.00527.x Abstract: Regional water management on the United States’ side of the middle and lower portions of the Rio Grande basin of Texas has been aided by a functioning water market since the early 1970s. The water market operates over a region that stretches from the Amistad Reservoir to the Rio Grande’s terminus into the Gulf of Mexico. This article provides an overview of the organizations, institutions, policies, and geographic particulars of the region’s water‐management system and its water market. In recent years, this region has experienced high population growth, periodic droughts, and a reallocation of water resources from the area’s agricultural sector to the municipal sector. Demand growth for potable water and a relatively fixed supply of raw water are reflected in increasing prices for domestic, municipal, and industrial water rights. Rising prices in the presence of scarcity and the transfer of water from lower‐value to higher‐value uses indicate that the market is operating as suggested by economic theory. Reasons for the market’s functionality are presented and discussed. Finally, suggestions are presented which might mitigate potential complications to market operations from aquifer depletion and aid the management of instream river flows.  相似文献   
704.
Determining the viability of protists and small microzooplankton has long been a focus of studies in marine biology and ecology. It is especially relevant in the issue of shipborne invasive species, and impending international guidelines and various national regulations on the allowable concentrations of organisms in discharged ballast water have spurred the growth of an industry that develops and manufactures ballast water management systems. The success of management systems and ability of ships to meet ballast water discharge standards is determined by the number of viable organisms in treated water. Here, we propose combining two vital, fluorescent stains (fluorescein diacetate [FDA] and 5-chloromethylfluorescein diacetate [CMFDA]) with direct microscopic observation to enumerate viable organisms ≥10 and <50 μm in minimum dimension (nominally protists). This approach was validated in four locations in the United States to determine the efficacy of the stains. Although the accuracy of the stains varied by geographic location and the taxonomic composition of the planktonic assemblage, combining fluorescent stains is a robust, powerful tool that can be optimized for the species present at each location. While this method was developed for analyzing viable organisms in treated ballast water, it may also be used or adapted for any field of research that examines a broad taxonomic range of autotrophic and heterotrophic plankton.  相似文献   
705.
706.
Of all natural disasters, flooding causes the greatest amount of economic and social damage. The United States' Federal Emergency Management Agency (FEMA) uses a number of hazard mitigation grant programmes for flood victims, including mitigation offers to relocate permanently repetitive flood loss victims. This study examines factors that help to explain the degree of difficulty repetitive flood loss victims experience when they make decisions about relocating permanently after multiple flood losses. Data are drawn from interviews with FEMA officials and a survey of flood victims from eight repetitive flooding sites. The qualitative and quantitative results show the importance of rational choices by flood victims in their mitigation decisions, as they relate to financial variables, perceptions of future risk, attachments to home and community, and the relationships between repetitive flood loss victims and the local flood management officials who help them. The results offer evidence to suggest the value of a more community-system approach to FEMA relocation practices.  相似文献   
707.
Arctic and subarctic ecosystems are experiencing substantial changes in hydrology, vegetation, permafrost conditions, and carbon cycling, in response to climatic change and other anthropogenic drivers, and these changes are likely to continue over this century. The total magnitude of these changes results from multiple interactions among these drivers. Field measurements can address the overall responses to different changing drivers, but are less capable of quantifying the interactions among them. Currently, a comprehensive assessment of the drivers of ecosystem changes, and the magnitude of their direct and indirect impacts on subarctic ecosystems, is missing. The Torneträsk area, in the Swedish subarctic, has an unrivalled history of environmental observation over 100 years, and is one of the most studied sites in the Arctic. In this study, we summarize and rank the drivers of ecosystem change in the Torneträsk area, and propose research priorities identified, by expert assessment, to improve predictions of ecosystem changes. The research priorities identified include understanding impacts on ecosystems brought on by altered frequency and intensity of winter warming events, evapotranspiration rates, rainfall, duration of snow cover and lake-ice, changed soil moisture, and droughts. This case study can help us understand the ongoing ecosystem changes occurring in the Torneträsk area, and contribute to improve predictions of future ecosystem changes at a larger scale. This understanding will provide the basis for the future mitigation and adaptation plans needed in a changing climate.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01381-1) contains supplementary material, which is available to authorized users.  相似文献   
708.
Adaptation to climate change has been recognized as very important in developing countries that face the greatest threats from global warming. In proposing various adaptation approaches, the United Nations Intergovernmental Panel on Climate Change required nations to prepare adaptation plans of action. However, the areas of priority in climate change adaptation have not been considered. This study has developed a new prioritization methodology for climate change adaptation in developing countries. Five categories and 25 approaches in climate change adaptation were adopted through a thorough and detailed analysis of pertinent literature related to the National Adaptation Program of Action (NAPA) in the Gambia. A fuzzy analytic hierarchy process-based questionnaire survey was designed and presented to 12 experts chosen from the committee members of the Gambia’s NAPA. The survey was made to determine the relative importance of the strategies for climate change adaptation. The results indicate that the five most important adaptation categories are health (0.223), forestry (0.213), water (0.210), food (0.181), and energy (0.174), with health as the number one priority in climate change adaptation. Further findings show that the prioritization order of the adaptation approaches to climate change in the Gambia is as follows: “Health education,” “public sensitization,” “water supply infrastructure development,” “microfinance,” and “infrastructure and technology enhancement.”  相似文献   
709.
Hand cranks are used in a variety of industries to actuate valves and in other gear-operated applications. In order to evaluate these types of operations and their compatibility with operator strength capabilities, a rotational dynamometer was used to measure torque production capability of operators using a hand crank at different heights and angles (with respect to the coronal plane). The tests were conducted for both clockwise and counterclockwise rotations using the dominant arm of each test participant. A total of 18 tests were completed by each of five male right-handed test participants. A 0° declination angle, counterclockwise operation, and both 40.65 cm and 60.96 cm heights were found to be associated with the greatest torque production capabilities.  相似文献   
710.
Opening and closing valves in industrial facilities often requires operators to use bars and wrenches as levers (cheaters) in order to overcome initial actuation forces. In order to determine more appropriate operational specifications, the maximum torque production capability was measured when 12 male participants used 4 different valve handwheels at 3 different heights and 2 different angles (in relationship to the coronal plane). The results indicate that the participants produced significantly greater torque when the largest of the 4 wheels (40.6 cm diameter) was used than when the medium (22.9 cm), small (20.3 cm), and handled (17.8 cm) handwheels were used. Although the main effect of heights was found to be statistically significant, post-hoc analyses between the heights found them to be, essentially, equal. In addition, the vertical and horizontal wheel orientations were not found to be different. The results are applicable to all industries where handwheels are used and applicable to valve manufacturers for designing operational torque specifications below the values found in this study.  相似文献   
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