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101.
Production of biodiesel is currently limited due to lack of economically beneficial feedstocks. Suitability of municipal wastewater sludge and olive mill waste as feedstocks for biodiesel production was evaluated. The various bio-waste sources were analyzed for their oil content and fatty acid composition using conventional analyses complemented with time domain (TD)-NMR analysis. TD-NMR, a rapid non-destructive method newly applied in this field, yielded good correlations with conventional methods. Overall biodiesel yields obtained by TD-NMR analysis were 7.05% and 9.18% (dry wt) for olive mill pomace and liquid wastes, and 11.92%, 7.07%, and 4.65% (dry wt) for primary, secondary, and anaerobically stabilized sludge, respectively. Fatty acid analysis indicated fundamental suitability of these agro-industrial waste resources for biodiesel production. Evaluation of bio-waste materials by TD-NMR revealed the potential of this tool to identify waste-oil sources cost effectively and quickly, supporting expansion of a sustainable biodiesel industry in Israel and other regions.  相似文献   
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/ We identified and ranked 108 resident and migratory wildlife taxa on John F. Kennedy Space Center (KSC) that were vulnerable to local, regional, or global extinction. We ranked taxa based on their vulnerability to extinction, their potential role for maintaining faunal integrity, and the relevance of KSC for maintaining their populations in the United States and Florida. Several taxa, not listed by agencies, were vulnerable to regional or global extinction. Many taxa not vulnerable to global extinction were vulnerable to local and regional extinction. Top predators were vulnerable to extinction because of small population size, isolation from other populations, and road mortality. Many taxa were dependent on habitat conditions at different geographic locations so that conservation required greater collaboration among land owners, managers, and researchers at local, regional, and global scales.KEY WORDS: Biological diversity; Endangered species; Conservation  相似文献   
103.
When evaluated at the scale of individual processes, next-generation technologies may be more energy and emissions intensive than current technology. However, many advanced technologies have the potential to reduce material and energy consumption in upstream or downstream processing stages. In order to fully understand the benefits and consequences of technology deployment, next-generation technologies should be evaluated in context, as part of a supply chain. This work presents the Materials Flow through Industry (MFI) supply chain modeling tool. The MFI tool is a cradle-to-gate linear network model of the US industrial sector that can model a wide range of manufacturing scenarios, including changes in production technology and increases in industrial energy efficiency. The MFI tool was developed to perform supply chain scale analyses in order to quantify the impacts and benefits of next-generation technologies and materials at that scale. For the analysis presented in this paper, the MFI tool is utilized to explore a case study comparing three lightweight vehicle supply chains to the supply chain of a conventional, standard weight vehicle. Several of the lightweight vehicle supply chains are evaluated under manufacturing scenarios that include next-generation production technologies and next-generation materials. Results indicate that producing lightweight vehicles is more energy and emission intensive than producing the non-lightweight vehicle, but the fuel saved during vehicle use offsets this increase. In this case study, greater reductions in supply chain energy and emissions were achieved through the application of the next-generation technologies than from application of energy efficiency increases.  相似文献   
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Communication of knowledge between the scientific and management communities is a difficult process complicated by the distinctive nature of professional career goals of scientists and decision-makers. This article provides a case history highlighting a collaboration between the science and management communities that resulted from a response to a 2004 hypoxia, or low dissolved oxygen, event in Long Bay, off Myrtle Beach, South Carolina. A working group of scientists and decision-makers was established at the time of the event and has continued to interact to develop a firm understanding of the drivers responsible for hypoxia formation in Long Bay. Several factors were found to be important to ensure that these collaborative efforts were productive: (1) genuine interest in collaboratively working across disciplines to examine a problem; (2) commitment by agency leadership, decision-makers, and researchers to create successful communication mechanisms; (3) respect for each others’ perspectives and an understanding how science and management are performed and that they are not mutually exclusive; (4) networking among researchers and decision-makers to ensure appropriate team members are involved in the process; (5) use of decision-maker input in the formulation of research and monitoring projects; and (6) commitment of resources for facilitation to ensure that researchers and decision-makers are communicating effectively.  相似文献   
105.
Phytoremediation which is a plant based remediation process is an emerging technology for treating inorganic (heavy metals) as well as organic pollutants. It may also be suitable for remediation of sites co-contaminated with heavy metals and organics which have become more prevalent. A glasshouse experiment was carried out to investigate the effect of 50 and 100 mg kg?1 of copper or 250 and 500 mg kg?1 of pyrene and the combined effect of copper and pyrene on the growth of Brassica juncea together with the uptake and accumulation of copper as well as dissipation of pyrene. Results showed a negative effect of copper–pyrene co-contamination on shoot and root dry matter and an inhibition of copper phytoextraction. Pyrene was significantly decreased in planted and non-planted soils accounting for 90–94% of initial extractable concentration in soil planted with B. juncea and 79–84% in non-planted soil which shows that the dissipation of pyrene was enhanced with planting. The occurrence of copper tended to increase the residual pyrene in planted soil, however in the presence of high concentration of Cu (100 mg kg?1), the residual pyrene concentration in soil were similar to those in unplanted soil. This may suggest that changes in the root physiology or rhizospheric microbial activity resulting from Cu stress could be an impediment to pyrene dissipation. The inhibition of Cu phytoextraction and degradation of pyrene by B. juncea under co-contamination may reduce the viability of phytoremediation in sites containing multiple pollutants.  相似文献   
106.
The monitoring of pharmaceuticals and personal care products (PPCPs) has focused on the distribution in rivers and small lakes, but data regarding their occurrence and effects in large lake systems, such as the Great Lakes, are sparse. Wastewater treatment processes have not been optimized to remove influent PPCPs and are a major source of PPCPs in the environment. Furthermore, PPCPs are not currently regulated in wastewater effluent. In this experiment we evaluated the concentration, and corresponding risk, of PPCPs from a wastewater effluent source at varying distances in Lake Michigan. Fifty-four PPCPs and hormones were assessed on six different dates over a two-year period from surface water and sediment samples up to 3.2 km from a wastewater treatment plant and at two sites within a harbor. Thirty-two PPCPs were detected in Lake Michigan and 30 were detected in the sediment, with numerous PPCPs being detected up to 3.2 km away from the shoreline. The most frequently detected PPCPs in Lake Michigan were metformin, caffeine, sulfamethoxazole, and triclosan. To determine the ecological risk, the maximum measured environmental concentrations were compared to the predicted no-effect concentration and 14 PPCPs were found to be of medium or high ecological risk. The environmental risk of PPCPs in large lake systems, such as the Great Lakes, has been questioned due to high dilution; however, the concentrations found in this study, and their corresponding risk quotient, indicate a significant threat by PPCPs to the health of the Great Lakes, particularly near shore organisms.  相似文献   
107.
The impact of diverse composition in teams is neither straightforward nor direct, and evidence suggests that diversity can be either conducive or detrimental to team innovation. Professionally diverse healthcare teams are increasingly used to develop innovative clinical approaches and solve complex healthcare problems; however, there is evidence that collaboration across professional boundaries creates conflict and is frequently unsuccessful. Healthcare organizations consequently face a dilemma. If they embrace professional diversity in teams, they risk interprofessional hostility, but if they choose homogeneous teams, they diminish their teams' capacity to innovate. We respond to this quandary by utilizing social identity theory to better understand the mechanisms through which professional diversity can enhance team innovation. In particular, we argue that professional identity salience operates as a mediator capable of explaining both positive and negative outcomes of professional diversity, contingent on the moderating effect of openmindedness norms. Analysis of survey data from 70 healthcare teams supports our model and indicates that professional salience can both enhance and undermine team innovation, depending on the extent of team openmindedness. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Rice: Reducing arsenic content by controlling water irrigation   总被引:2,自引:0,他引:2  
<正>Arsenic has long been recognized as a poison.Arsenic in water supplies that are used for both drinking and crop irrigation can expose many people chronically to elevated levels of arsenic.The main health concern for chronic exposure to arsenic is the development of cancer.Although the World Health Organization(WHO)recommends that total arsenic in drinking water should be under 10μg/L(or 10 ppb),(WHO,2011),some regions  相似文献   
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