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51.
The feasibility of applying the up-flow anaerobicsludge blanket (UASB) treatment for poultry waste (faeces)water was examined. A continuous-flow UASB pilot scalereactor of 3.50 L capacity using mixed culture was operatedfor 95 days to assess the treatability of poultry waste-water and its methane production. The maximum chemicaloxygen demand (COD) removed was found to be 78% whenorganic loading rate (OLR) was 2.9 kg COD m-3 day-1 athydraulic retention times (HRT) of 13.2 hr. The averagebiogas recovery was 0.26 m3 CH4 kg COD with an averagemethane content of 57% at mean temperature of 30 °C.Data indicate more rapid methanogenesis with higher loadingrates and shorter hydraulic retention times. At feedconcentration of 4.8 kg COD m-3 day-1, anaerobic digestionwas severely retarded at all hydraulic retention timetested. This complication in the reactor operations may belinked to build-up of colloidal solids often associated withpoultry waste water and ammonia toxicity. Isolates fromgranular sludge and effluent were found to be facultativeanaerobes most of which were Pseudomonas genera.  相似文献   
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In 1992, Eaton Corporation, a major manufacturer of vehicle components and electrical and electronic controls, implemented a fast-track remediation method to expedite the installation of a groundwater recovery and treatment system to contain and mitigate a chlorinated solvent plume at an industrial site. This dual-track method included fast-track and turnkey project management techniques. Our goal was to expedite the containment and removal of identified contamination, which would protect the environment, minimize future liability, and significantly reduce remediation time and costs. This goal was in the best interests of all concerned—Eaton, the community, and the state regulatory agency. This strategy took the project from dual-track concept approval by the regulatory agency to remediation system installation and start-up in less than eight months, cutting over two years from the standard Remediation Investigation/Feasibility Study (RI/FS) approach, with consequent earlier contaminant containment. Total remediation costs were half of what they would have been under the standard RI/FS procedure for this site.  相似文献   
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Coastal areas are threatened under climate change because of factors related to vulnerability of society and sensitivity of the environment. Protection and adaptation may mitigate the adverse consequences. This research reviews and assesses the options of protection by homeowners in the coastal zone in the southwest region of Cameroon. The coastal zone of Cameroon is studied because of the observed deleterious effect of recent extreme climatic events. From a research sample of 400 households, the house types and protection strategies - which are of two main types: reactive measures and preventive measures taken to offset adverse effects on property, are studied. A multinomial logit function reveals that income, education, age and gender are significant factors determining household’s probability on the selection of protection measures. The study concludes that there are strong implications for adaptation to future climate change, and the ability of homeowners to extensively respond will have to be reinforced not only by communal and public works projects but also through an active government policy to promote climate change adaptation.  相似文献   
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This study contends that climatic events such as storms and floods may significantly impact on cost of protection through climate proofing of housing structures along the Atlantic coastal zone in the Southwest region of Cameroon. Household level protection is purposely examined on the rationale that current protective efforts constitute the building blocks for long-term adaptation. Examining the determinants of the cost of current protection stands good stead to better inform policy to promote future adaptation to climatic stress. Hence, from a research sample of 400 households, the study estimates a function that relates household-level protection costs to their characteristics. Sixty-four percent of the homes studied have been hit at least once by strong winds, and an average of 2 times in the last 5 years, and 36% of houses have once been hit by storm surge from the sea nearby. With an average monthly income of 120.000 FCFA (US285), the coastal residents spend on average 145,500 FCFA (US 285), the coastal residents spend on average 145,500 FCFA (US 346) in preparation against floods. The statistical estimates of the cost function reveal significant positive signs, implying that the experiences and location of homes within floodplain increases the cost of protection no matter the structural characteristics of the house. The study observes that the proximity to the coast and in flood plains significantly increases the cost of protection, and the ability to invest in preventive measures and climate proofing housing structures increase as individual income grows. The findings indicate the need for improvement of monitoring and forecasting systems for floods, intensification of awareness and proper urban planning. The policy implications are reinforced by the low incomes of most residents, as this calls for external assistance through transfer of planning skills, capital and public options to reinforce the resilience and choices made at the household level.  相似文献   
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Volatile organic chloramines are reported as the disinfection byproducts during chlorination or chloramination.However,ClO_2,as an important alternative disinfectant for chlorine,was not considered to produce halogenated amines.In the present work,volatile organic chloramines including(CH_3)_2 NCl and CH_3 NCl_2 were found to be generated during the reaction of ClO_2 and the dye pollutants.(CH_3)_2 NCl was the dominant volatile DBP to result from ClO_2 treated all four dye pollutants including Methyl Orange,Methyl Red,Methylene Blue and Malachite Green,with molar yields ranging from 2.6% to 38.5% at a ClO_2 to precursor(ClO_2/P) molar ratio of 10.HOCl was identified and proved to be the reactive species for the formation of (CH_3)_2 NCl,which implied(CH_3)_2 NCl was transformed by a combined oxidation of ClO_2 and hypochlorous acid.(CH_3)_2 NCl concentrations in the ppb range were observed when real water samples were treated by ClO_2 in the presence of the dye pollutants.The results suggest that these azo dyes are one of the significant precursors for the formation of HOCl during ClO_2 treatment and that organic chloramines should be considered in ClO_2 disinfection chemistry and water treatment.  相似文献   
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National Flood Interoperability Experiment (NFIE) derived technologies and workflows will offer the ability to rapidly forecast flood damages. Address Points used by emergency management personnel approximate the locations of buildings, and they are a common operating picture for emergency responders. Most United States (U.S.) county tax assessment offices throughout the contiguous U.S. (CONUS) produce georeferenced cadastral data. To varying degrees, these parcel data describe building characteristics of structures within the parcel. Address Point data with cadastral data offers the ability to rapidly develop building inventories for flood damage estimation. Flood damage forecasts can expedite recovery and improve short‐term flood resilience. In this work the authors evaluate Flood Damage Wizard, a proposed open source platform independent methodology. Flood Damage Wizard uses point shapefile building information to estimate flood damage to buildings by finding the appropriate depth‐damage function using fuzzy‐text matching. The authors apply Flood Damage Wizard using Address Point and parcel datasets to demonstrate a method of estimating flood damage to buildings nearly anywhere within the CONUS. Results indicate using Address Point and cadastral datasets can generate total flood damage estimates approximate to those estimated using existing software solutions Hazus‐MH and HEC‐FIA with minimal manual processing of input data.  相似文献   
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