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111.
An aerobic fixed film biological treatment system has been successfully treating recovered groundwater/landfill leachate containing 1,4‐dioxane, tetrahydrofuran (THF), and other constituents since 2003. The most likely mode of 1,4‐dioxane biotransformation is via a cometabolic pathway in the presence of THF. Pilot studies conducted during the process development phase established a design basis process loading factor of 0.6 g 1,4‐dioxane and THF (as chemical oxygen demand [COD])/g total solids per day and proved the efficacy of the process. Full‐scale design includes the use of three parallel moving bed bioreactors with effluent recycle capability. Removal efficiencies in excess of 98 percent have been documented for 1,4‐dioxane. Evolving operational challenges are associated with recent trends in 1,4‐dioxane pretreatment discharge limitations in combination with ongoing process optimization and increased influent flow rate conditions associated with seasonal precipitation patterns. ©2016 Wiley Periodicals, Inc.  相似文献   
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Career success is a main focus of career scholars as well as organizational stakeholders. Historically, career success has been conceptualized and measured in an objective manner, mainly as salary, rank, or number of promotions. However, the changing nature of work has also necessitated a change in the way many employees view success, adding a more subjective component. Although there has been theoretical discussion and calls to develop a comprehensive measure of subjective career success, no contemporary comprehensive quantitative measure exists. The goal of this study was to create and validate a measure of subjective career success, titled the Subjective Career Success Inventory (SCSI). The SCSI includes 24 items that address subjective career success via eight dimensions. The scale was developed and validated through four phases of data collection, beginning with interviews and focus groups, followed by item sorting tasks, then item refinement through confirmatory factor analysis, and finally convergent and discriminant validity quantitative analysis. Theoretical and practical implications are discussed. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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ABSTRACT: Statutory and case law at the state level provide critical legal frameworks for water management. As many state governments struggle to improve efficiency in water management and resolve conflicts over water usage, they must continually assess the efficacy of their state water law. Most states have water laws that are disconnected and overlapping. This article presents a methodology to assess state water law and take first steps toward a comprehensive state water resources act. The methodology is driven by issues and conflicts in water management. It synthesizes management and legal analyses into a process that incorporates the diverse perspectives of state water stakeholders. The results of the analysis are identification of management issues, profiles of state water law, and explorations of legal options that are available to the state government. Illinois is provided as a case study for this methodology.  相似文献   
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As part of a large exposure assessment and health-effects panel study, 33 trace elements and light-absorbing carbon were measured on 24-hr fixed-site filter samples for particulate matter with an aerodynamic diameter <2.5 microm (PM2.5) collected between September 26, 2000, and May 25, 2001, at a central outdoor site, immediately outside each subject's residence, inside each residence, and on each subject (personal sample). Both two-way (PMF2) and three-way (PMF3) positive matrix factorization were used to deduce the sources contributing to PM2.5. Five sources contributing to the indoor and outdoor samples were identified: vegetative burning, mobile emissions, secondary sulfate, a source rich in chlorine, and a source of crustal-derived material. Vegetative burning contributed more PM2.5 mass on average than any other source in all microenvironments, with average values estimated by PMF2 and PMF3, respectively, of 7.6 and 8.7 microg/m3 for the outdoor samples, 4 and 5.3 microg/m3 for the indoor samples, and 3.8 and 3.4 microg/m3 for the personal samples. Personal exposure to the combustion-related particles was correlated with outdoor sources, whereas exposure to the crustal and chlorine-rich particles was not. Personal exposures to crustal sources were strongly associated with personal activities, especially time spent at school among the child subjects.  相似文献   
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Environmental Science and Pollution Research - The co-occurrence of mixtures of glyphosate (GLP) and aminomethylphosphonic acid (AMPA) in contaminated water, soil, sediment, and plants is a cause...  相似文献   
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Passive acoustic and synchronous video recordings were made at two spawning aggregation sites to study the sounds associated with reproductive behaviors of Mycteroperca bonaci. A characteristic sound was produced during courtship displays involving behaviors commonly observed for groupers of this genus at aggregations. The sound has a short pulsing section followed by a longer tonal portion with a mean peak frequency below 100 Hz. Courtship-associated sounds were quantified over one spawning season at Mona Island, Puerto Rico. Most of the daily sound production occurred during a period of 2 h prior to sunset. The highest rates of sound production lasted for a period of 10 days with lunar periodicity over three consecutive months coincident with the reported season of reproduction. Passive acoustics provide a tool to measure the variability of the reproductive activity of M. bonaci over time and may provide a method to evaluate current strategies designed to protect multi-species spawning aggregations that are critical for the recovery of threatened groupers.  相似文献   
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Humpback whales (Megaptera novaeangliae) in the Southeastern Atlantic Ocean (International Whaling Commission ‘Breeding Stock B’—BSB) are distributed from the Gulf of Guinea to Western South Africa. Genetic data suggest that this stock may be sub-structured, but it remains unknown if this is due to reproductive segregation. This paper evaluates the spatial and temporal population structure of BSB humpback whales using a combination of maternally and bi-parentally inherited markers. The genetic differentiation that we identify in this study could be due to a combination of (1) spatial and/or temporal segregation on breeding grounds in the greater Gulf of Guinea, (2) the possibility of maternally inherited site fidelity to specific feeding grounds and (3) the use of two generalized but exclusive migratory routes (coastal and offshore) between feeding and breeding areas. Further, photo-identification and genetic sampling efforts in other areas of the Sub-Saharan Western Africa winter range and targeted deployment of satellite tags would help to clarify some of the apparent complexity in the population structure of animals biopsied in this region.  相似文献   
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