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991.
Background, Aim and Scope Agricultural industrial wastes can frequently be used as raw materials in the production of bio-fuels. Olive-oil milling wastewater is considered as one of the most polluting agro-industrial residues, but fortunately due to its high content of organic matter, it has the potential to be a valuable starting material to obtain bio-ethanol via fermentation with Saccharomyces cerevisiae. The fermentation of olive-oil milling wastewater has been demonstrated with good yield of ethanol (8-12%v/v) once the level of reducing sugars is appropriate and the phenolic fraction, which inhibits the yeast, is removed. Materials and Methods: - Results: - Discussion: - Conclusions: - Recommendations and Perspectives: -  相似文献   
992.
A carefully designed survey of medical waste management was undertaken in Dhaka, the capital city of Bangladesh. A range of sampling strategies and data gathering techniques were used. The data gathering techniques included observation, formal structured interview and informal dialogue. Sampling strategies included formal representative sampling for fixed populations and adaptive sampling for roaming populations was developed. Data were collected from healthcare establishments (HCEs) and other waste disposal operatives.Operatives dealing with waste were frequently found to be untrained, and without even a basic understanding of the hazards involved. Personal protective equipment was inadequate in most cases which led to frequent accidental injuries. No HCE was found to have adequate storage facilities for hazardous waste. Thus scavengers were able to gain access to items such as syringes and expired medicines, which they repackaged and resold. The lack of correctly controlled internal storage may be linked to the observation that employees at many HCEs offered contaminated items for sale to scavengers and recycling operatives. In many cases there was no attempt at segregation, but in some cases there was segregation at the point of use, but subsequent remixing with general waste, indicating a lack of management and education rather than a lack of will. In either case, hazardous waste was dumped in city corporation bins, and disposed of on general landfill sites. As well as exposing the waste to scavengers, this could potentially contaminate ground water, especially as the dumps were located in areas subject to frequent flooding.  相似文献   
993.
The present study reports concentrations of polybrominated diphenyl ethers (PBDEs) and organochlorines (OCs) in human breast milk from Indonesia covering urban, suburban and rural areas. PBDEs were detected in all the samples of the present study with total concentrations ranging from 0.49 to 13 ng/g lipid wt. Geographical distribution showed that concentrations of PBDEs were relatively uniform (p>0.05) and the levels were in the same order as those in Japan and some European countries, but were one or two order lower than North America. When compared to OCs, the level of total PBDEs was lower. The congener pattern was in accordance with other studies on human matrices, in which BDE-47 was the most abundant congener. Variations of PBDE congeners in human breast milk were further discussed to elucidate the potential exposure source(s) and pathways.  相似文献   
994.
This study sought to determine the lowest number of storm events required for adequate estimation of annual nutrient loads from a forested watershed using the regression equation between cumulative load (∑L) and cumulative stream discharge (∑Q). Hydrological surveys were conducted for 4 years, and stream water was sampled sequentially at 15-60-min intervals during 24 h in 20 events, as well as weekly in a small forested watershed. The bootstrap sampling technique was used to determine the regression (∑L-∑Q) equations of dissolved nitrogen (DN) and phosphorus (DP), particulate nitrogen (PN) and phosphorus (PP), dissolved inorganic nitrogen (DIN), and suspended solid (SS) for each dataset of ∑L and ∑Q. For dissolved nutrients (DN, DP, DIN), the coefficient of variance (CV) in 100 replicates of 4-year average annual load estimates was below 20% with datasets composed of five storm events. For particulate nutrients (PN, PP, SS), the CV exceeded 20%, even with datasets composed of more than ten storm events. The differences in the number of storm events required for precise load estimates between dissolved and particulate nutrients were attributed to the goodness of fit of the ∑L-∑Q equations. Bootstrap simulation based on flow-stratified sampling resulted in fewer storm events than the simulation based on random sampling and showed that only three storm events were required to give a CV below 20% for dissolved nutrients. These results indicate that a sampling design considering discharge levels reduces the frequency of laborious chemical analyses of water samples required throughout the year.  相似文献   
995.
东平湖是南水北调东线的重要调蓄湖,其水环境状况对输水安全具有重要意义.为分析与评价东平湖底泥重金属污染状况及其与摇蚊分布关系,采集30个东平湖底泥样品,分别测试和鉴定其中的元素含量和摇蚊亚化石种属.运用地积累指数和生态危害指数法对东平湖底泥重金属污染进行分析评价,发现Cu、Pb、Zn、Ni是主要污染物,但污染程度相对较低,整体为轻度—中度污染水平,潜在生态危害性为轻微水平,且其污染及危害性均呈现出由湖区东南向西北逐渐降低的空间分布特征.其中,Cu污染最为严重,部分地区达到强污染水平.东平湖底泥共鉴定出41个摇蚊属种,主要优势种由Stempellinella-Zavrelia(30.88%)、Propsilocerus akamusi-type(26.79%)、Paratanytarsus(10.34%)、Cricotopus sylvestris-type(7.52%)和Hydrobaenus conformis-type(5.19%)组成.Stempellinella-Zavrelia和Propsilocerus akamusi-type是东平湖的绝对优势种,合占全湖的57.67%,且几乎呈全湖性分布.摇蚊RDA分析显示第一轴特征值为0.073,摇蚊种属与环境的相关关系达到了58.4%.RDA结果表明影响摇蚊组成分布的显著因子是Mn,并解释了7.3%的摇蚊变率.摇蚊属种Stempellinella-Zavrelia、Propsilocerus akamusi-type、Paratanytarsus、Hydrobaenus conformis-type等分布在Mn污染较小的区域.Pearson相关分析进一步表明东平湖底泥不同摇蚊种属对重金属Mn污染的响应存在显著差异.总体来看,底泥重金属对东平湖摇蚊组成和分布有显著影响,但不同金属对其影响存在差异.  相似文献   
996.
Phytoplankton and benthic vegetation biomass undergoes spatial-temporal changes in relation to their life cycle, but also to meteorological conditions, physical-chemical variables, organic input and internal dynamism. The main aim of this work was to observe the effect of all environmental variables on the vegetative dynamic process in a protected zone of a Mediterranean costal lagoon (Lesina lagoon, SE Italy). Seven samplings were performed from 2010 to 2012 at 30 sites for nutrient and chlorophyll analyses, while TOC measurements and wet biomass evaluation were performed at 10 sites. Temperature, salinity and oxygen saturation were also measured by multiparametric probe and a visual census for vegetation was performed. Sites close to freshwater inflow were characterized by lower temperature and salinity, and high nitrate, with maxima of 191.05 μM in May 2010 and more than 250 μM in October 2010. Silicates drastically decreased from May 2010 (87.57 μM) to July 2010 (6.15 μM) and increased again in October (74.99 μM). Chl a concentrations were not on average higher than 6 mg m?3, but peaks of 20 mg m?3 were observed during May 2011 and May 2012. Benthic vegetation wet biomass collected in 2010 was approximately twice that collected in 2012, with a maximum of 27,554 g m?2 and a dominance of macroalgae (70 % in May 2010 and 40 % in August 2010). During period 2010, a simultaneous and drastic decreasing of both mean values of wet biomass and chl a was observed from May to October 2010. During period 2012 a shift of vegetation biomass was shown from May (phytoplankton prevalence) to August 2012, with angiosperm prevalence (more than 30 %).  相似文献   
997.
Thirty samples of Chinese medicines and herbs were analyzed using instrumental neutron activation analysis (INAA) and X-ray diffraction (XRD) methods, mainly noting on the hazardous elements arsenic (As), mercury (Hg), chromium, antimony and cobalt. The three Niuhuang Jiedu Pian samples contained 8.6%, 8.3% and 2.2% As. Two out of four Liushen Wan samples contained approximately7% of both As and Hg. Despite being identically named, the other two Liushen Wan samples did not contain such high concentrations. Japanese Liushen Wan for children contained 1.2 ± 0.03% As and 31 ± 12 mg/kg Hg, whereas Liushen Wan for adults manufactured by another Japanese company contained 550 ± 22 mg/kg As and 1.2 ± 0.05 mg/kg Hg. All the chemical structural formulas of As and Hg in the high-concentration Niuhuang Jiedu Pian and Liushen Wan were realgar (As4S4), uzonite (As4S5) and cinnabar (HgS). Although the human body is generally not believed to absorb sulphides, continuous intake of these Chinese medicines is potentially no good because it is possible that some arsenic-sulfides will dissolve in gastric acid and then alter their chemical structures. Additionally, many herbs contained low concentrations of Hg, and their chemical structures were unknown.  相似文献   
998.
The aim of this field study was to determine the concentrations and emissions of ammonia and hydrogen sulfide in different types of pig buildings in Korea to allow objective comparison between pig housing types in Korea and other countries. Concentrations of ammonia and hydrogen sulfide in the pig buildings averaged 7.5ppm and 286.5ppb and ranged from 0.8 to 21.4ppm and from 45.8 to 1235ppb, respectively. The mean emissions of ammonia and hydrogen sulfide per pig (normalized to 75kg liveweight) and area (m2) from pig buildings were 250.2 and 37.8mg/h/pig and 336.3 and 50.9mg/h/m2, respectively. Ammonia and hydrogen sulfide concentrations and emissions were higher in the pig buildings managed with deep-pit manure systems with slats and mechanical ventilation than in other housing types.  相似文献   
999.
In Japan, the Renewable Portfolio Standard (RPS) and the Feed-in-Tariff (FIT) have been used for the exploitation of renewable energy sources (RES). Although these are significant to enhance the use of RES, the RES penetration is not reaching the expected percentage. The identification of their strengths/weaknesses will allow their improvement for achieving the target. This paper concerned the evaluation of RPS and FIT using a multi-criteria evaluation method. First, official data/information were used to assess their performance using the method. Second, national experts were asked about their performance to verify the outcomes. We found FIT was more effective than RPS.  相似文献   
1000.
Bacteriophages MS-2 and PRD-1 were used as indicators of human viral behaviour in a series of turf-grass irrigation and washing machine experiments to provide information about the level of human exposure to potential residual enteric viruses in recycled water that can affect health. Results provided evidence to support a potential inadvertent exposure volume of 0.01 ml for recycled water used for machine clothes washing. Results for irrigation experiments showed that a one log reduction in bacteriophage numbers on turf-grass was not achieved under exposure to high solar conditions after 4 h. Experimentation showed that bacteriophages may be usefully employed in exposure assessment studies based on the ease of their enumeration and logistical and cost considerations. In terms of future studies, observed differences in individual bacteriophage characteristics provide a rationale for using multiple viral indicators. However, limitations on the utility of bacteriophage also need to be considered.  相似文献   
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