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61.
This study was conducted to evaluate the treatability of OMW (olive mill wastewater) with sewage and sewage sludge, which could supplement nutrients and microbes required for OMW treatment and reduce its possible toxicity. The amount of OMW added to an aeration tank was based on the loading difference between the designed and actual COD loads, while the amount added to anaerobic digestion for energy recovery was determined by CH4 production. The COD removal efficiencies were 70-85% for both systems. Compost of OMW with dried sewage sludge also showed a similar temperature profile without OMW addition. This strongly suggested that OMW can be treated at a sewage plant without pretreatment and the treated effluent can be reused in irrigation for an arid region.  相似文献   
62.
Domestic wastewater is a significant source of nitrogen and phosphorus, which cause lake eutrophication. Among the wastewater treatment technologies, constructed wetlands are a promising low-cost means of treating point and diffuse sources of domestic wastewater in rural areas. However, the sustainable operation of constructed wetland treatment systems depends upon a high rate conversion of organic and nitrogenous loading into their metabolic gaseous end products, such as N2O and CH4. In this study, we examined and compared the performance of three typical types of constructed wetlands: Free Water Surface (FWS), Subsurface Flow (SF) and Vertical Flow (VF) wetlands. Pollutant removal efficiency and N2O and CH4 emissions were assessed as measures of performance. We found that the pollutant removal rates and gas emissions measured in the wetlands exhibited clear seasonal changes, and these changes were closely associated with plant growth. VF wetlands exhibited stable removal of organic pollutants and NH3-N throughout the experiment regardless of season and showed great potential for CH4 adsorption. SF wetlands showed preferable T-N removal performance and a lower risk of greenhouse gas emissions than FWS wetlands. Soil oxidation reduction potential (ORP) analysis revealed that water flow structure and plant growth influenced constructed wetland oxygen transfer, and these variations resulted in seasonal changes of ORP distribution inside wetlands that were accompanied by fluctuations in pollutant removal and greenhouse gas emissions.  相似文献   
63.
Estrogenic personal care products in a greywater reuse system.   总被引:1,自引:0,他引:1  
The occurrence and fate of parabens in a greywater system was assessed. The potential for removal of residual paraben concentrations in effluent greywater with chlorine dioxide was also investigated. The influent to the greywater plant was characterised by considerable variation, with concentrations from below the detection limit to 40 microg/L and the five commonly used parabens in consumer products were frequently detected. After the biological treatment only two paraben were detected with concentration from 65-120 ng/L. Chlorine dioxide treatment of the biologically treated effluent with dosages down to 0.75 mg/L resulted in more than 97% reduction of all parabens. Formation of the by-product chloroform was insignificant from the chlorine dioxide treatment.  相似文献   
64.
Water and sediment samples from 29 locations in the Detroit and St. Clair rivers were analyzed for the highly toxic tri-n-butyltin (Bu3Sn+) species and for the less toxic di-n-butyltin (Bu2Sn2+) and n-butyltin (BuSn3+) species and inorganic tin. In general, locations sampled in the St. Clair River were less contaminated with butyltin species than those in the Detroit River. Inorganic tin and BuSn3+ were detected in over 90% of all subsurface water samples, while Bu2Sn2+ and Bu3Sn+ were detected in 45 and 28% of the same samples, respectively. The highest concentration ofBu3Sn+ in subsurface water, 5.9 × 10?10 mol Sn/L, was at the mouth of the Ecorse River, a tributary of the Detroit River. The three butyltin species and inorganic tin were also detected in 23–46% of all sediment samples. The highest concentrations of Bu3Sn+ in sediment were found close to the mouths of the River Rouge, another tributary of the Detroit River, and the Ecorse River, and were 6.2 × I0–7 and 1.7 × I0–7 mol Sn/kg dry weight, respectively, for the top 2 cm of sediment.  相似文献   
65.
BOOK REVIEW     
Emerging Financial Markets, by David O. Beim and Charles W. Calomiris. McGraw‐Hill/Irwin, 2001, 364 pages, price $75.00.  相似文献   
66.
67.
在巴西伊加拉帕瓦水电站,通过监测电气气隙,避免了一台新水轮发电机发生重大破坏和昂贵的停机事故.  相似文献   
68.
This paper presents the development andvalidation of new measurement tools to exploreself-efficacy toward service and toward civicparticipation. We developed and administereda survey to 851 students in an AACSB-accreditedcollege of business at a comprehensive publicuniversity located in the Midwest. Traditionalscale development methodologies plusconfirmatory factor analysis and simultaneousfactor analysis in several populations wereused to analyze both a primary sample and aholdback sample. Results strongly support thevalidity and reliability of the surveyinstrument. Future use for the instrumentincludes verification of the effectiveness ofpedagogies designed to increase self-efficacytoward service and motivation for civicparticipation in business students.  相似文献   
69.
More ethics research needs to explore the global differences in ethical evaluations. This study explored the relationships among nationality, teleological evaluations, ethical judgments, and ethical intentions using a sample of 222 American and Spanish business professionals. The path analysis indicated that teleological evaluations were related to ethical judgments and that both ethical judgments and teleological evaluations were related to ethical intentions. Executive nationality was related to teleological evaluations and ethical intentions with American individuals having higher teleological assessments and intentions to act ethically than the Spanish individuals. These findings have implications for global companies, which are presented along with the study's limitations and future research suggestions.  相似文献   
70.
This study examines how two dimensions of strategic orientation (customer and competitor orientation) influence logistics and market performance. Two capabilities, operational flexibility and collaboration, are studied. Data were collected from manufacturers working with third party logistics providers. The findings suggest that customer and competitor orientations have different influences upon performance when leveraged through the capabilities. Competitor orientation, while having a detrimental direct effect on logistics performance, appears to be the better strategic approach, when supported with operational flexibility since it results in enhanced logistics (efficiency) and market (effectiveness) performance. Customer orientation, on the other hand, greatly improves logistics performance, i.e., internal efficiency.  相似文献   
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