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241.
The purpose of this study was to assess metal concentrations (Al, Cd, Pb, Hg and Ni) in Sabal drainage canal (Al-Menoufiya Province, River Nile Delta, Egypt) water as well as their accumulation in some selected organs (skin, muscles and kidneys) of Oreochromis niloticus fish to evaluate their hazard levels in relation to the maximum residual limits for human consumption. Drainage canal water was found to be heavily polluted with metals which far exceeded the permissible limits. It was found that metals accumulated in organs of O. niloticus in concentrations higher than those of canal water. Kidneys of O. niloticus contained the highest concentrations of the detected metals, while skin appeared to be the least preferred site for the bioaccumulation of metals as the lowest metals concentrations were detected in this tissue. The present study shows that fish organs contained high levels of metals exceeding the permissible limits values. Metals in muscle of fish were higher than the maximum permissible concentrations for human consumption. Thus, consuming fish caught from drainage canals is harmful to the consumers.  相似文献   
242.
Because of the recent frequent observations of major dust storms in southwestern cities in Iran such as Ahvaz, and the importance of the ionic composition of particulate matters regarding their health effects, source apportionment, etc., the present work was conducted aiming at characterizing the ionic composition of total suspended particles (TSP) and particles on the order of ~10?μm or less (PM(10)) during dust storms in Ahvaz in April-September 2010. TSP and PM(10) samples were collected and their ionic compositions were determined using an ion chromatography. Mean concentrations of TSP and PM(10) were 1,481.5 and 1,072.9?μg/m(3), respectively. Particle concentrations during the Middle Eastern Dust (MED) days were up to four times higher than those in normal days. Ionic components contributed to only 9.5% and 11.3% of the total mass of TSP and PM(10), respectively. Crustal ions were most abundant during dust days, while secondary ions were dominant during non-dust days. Ca(2+)/Na(+) and Cl(-)/Na(+) ratios can be considered as the indicators for identification of the MED occurrence. It was found that possible chemical forms of NaCl, (NH(4))(2)SO(4), KCl, K(2)SO(4), CaCl(2), Ca(NO(3))(2), and CaSO(4) may exist in TSP. Correlation between the anionic and cationic components suggests slight anion and cation deficiencies in TSP and PM(10) samples, though the deficiencies were negligible.  相似文献   
243.
Manchar Lake is the largest natural freshwater lake in Pakistan. The Lake has received less fresh water in past few years. In addition, drainage water is being discharged in the Lake through Main Nara Valley Drain (MNVD) since many years. Consequently, concern has grown regarding the water quality of the Lake. The aim of this study was to assess the water quality of Manchar Lake and MNVD and the objectives were to determine physiochemical properties and the concentrations of common cations and anions as well as seven trace metals i.e. Cu, Ni, Zn, Co, Fe, Pb and Cd. The concentration of the trace metals were determined by simultaneous preconcentration and solvent extraction using flame atomic absorption spectrometer. Results of physicochemical parameters of Manchar Lake water samples showed mean pH 8.4 (±0.2), conductivity 2,310.3 (±581.3) μS cm−1 and hardness (as CaCO3) 213.1 (±62.3) mg l−1. Mean concentrations of cations and anions were Na 521.5 (±49.7), Cl 413.6 (±225.7), Ca 70.7 (±12.9), Mg 56.2 (±28.9), K 17.6 (±6.5), 0.34 (±0.2) and 0.02 (±0.01) mg l−1. Mean concentrations of trace metals were Zn 15.7 (±1), Fe 12 (±3.5), Pb 9 (±2.7), Cu 8.9 (±7.7), Ni 4.3 (±3.4), Co 4 (±3.4) and Cd 1.1 (±1) μg l−1. MNVD water samples showed mean pH 8.9 (±0.8), conductivity 1,735.7 (±567.8) μS cm−1 and hardness (as CaCO3) 184.8 (±32.4) mg l−1. In MNWD, the mean concentrations of cations and anions were Na 482.7 (±11.7), Cl 395.7 (±271.5), Ca 79.1 (±23.5), Mg 54.2 (±28.1), K 26.2 (±21.3), NO−3 0.5 (±0.3) and 0.1 (±0.1) mg l−1. Mean concentrations of trace metals observed in MNWD water were Fe 14.9(±3.5), Cd 8.3 (±9.4), Pb 6.9 (±2.4), Cu 6.6 (±3.1), Zn 6.2 (±1.8), Co 4.5 (±2.7), and Ni 3.5 (±2.9) μg l−1. The pH of both Manchar Lake and MNVD waters and concentration of Pb in Manchar Lake and concentration of Cd in MNVD water were higher than the World Health Organisation’s guideline values for the drinking water quality. The water quality of Manchar Lake was found degraded.  相似文献   
244.

The aim of the current research was to recognize consumer attitude gap toward green brand by studying role of green consumer value and green brand equity toward the switching intention and purchase intention of consumers toward green brands. The current research employed quantitative research design and collected data through questionnaire from 331 respondents. The PLS-structural equation modeling was employed to analyze the structured relationships. The findings suggest green customer value is product of the three important factors namely green brand experiential risk, green brand experiential quality and green brand experience. Hence, these act as the main drivers of switching consumer behavioral intention toward the green products through consumer green brand equity. The research attempts to study the attitude–behavior gap in the green marketing literature by investigating the role which includes, green brand experiential risk, green brand experiential quality and green brand experience on customer value leading to green brand equity. The research provide an in-depth understating of attitude–behavior gaps and role of green customer value and brand equity that plays vital role in marketing campaigns and policy making to increase purchase intention of green eco-conscious products.

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245.
Hospital site selection using fuzzy AHP and its derivatives   总被引:2,自引:0,他引:2  
Environmental managers are commonly faced with sophisticated decisions, such as choosing the location of a new facility subject to multiple conflicting criteria. This paper considers the specific problem of creating a well-distributed network of hospitals that delivers its services to the target population with minimal time, pollution and cost. We develop a Multi-Criteria Decision Analysis process that combines Geographical Information System (GIS) analysis with the Fuzzy Analytical Hierarchy Process (FAHP), and use this process to determine the optimum site for a new hospital in the Tehran urban area. The GIS was used to calculate and classify governing criteria, while FAHP was used to evaluate the decision factors and their impacts on alternative sites. Three methods were used to estimate the total weights and priorities of the candidate sites: fuzzy extent analysis, center-of-area defuzzification, and the α-cut method. The three methods yield identical priorities for the five alternatives considered. Fuzzy extent analysis provides less discriminating power, but is simpler to implement and compute than the other two methods. The α-cut method is more complicated, but integrates the uncertainty and overall attitude of the decision-maker. The usefulness of the new hospital site is evaluated by computing an accessibility index for each pixel in the GIS, defined as the ratio of population density to travel time. With the addition of a new hospital at the optimum site, this index improved over about 6.5 percent of the geographical area.  相似文献   
246.
Persistent organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), alpha, beta and gamma-hexachlorocyclohexane (HCH) isomers, together with polychlorinated biphenyl (PCB) congeners (IUPAC Nos. 28, 52, 101, 138, 153 and 180), were determined in tail feathers from 37 birds belonging to 18 species, all originating from the South-West of Iran (Khuzestan, coast of the Persian Gulf). This is the first report on organochlorine contaminants in feathers from museum collections and it is an indication of the concentrations of OCPs and PCBs in the past (1991-1996). Median concentrations of HCHs, DDTs, PCBs and HCB were 22, 14, 11 and 10 ng/g feather, respectively. Significant correlations (p<0.05) were calculated between OCPs (except HCB) and PCBs in the bird feathers. p,p'-DDE and gamma-HCH were the most abundant OCPs, while CB 180, CB 138 and CB 101 were the predominant PCB congeners in almost all species. Significant differences (p<0.05) in the mean concentrations of DDTs and PCBs were detected among species grouped according to their feeding habits. Levels of DDTs and PCBs were highest in the carnivorous species and lowest in the herbivorous species. Levels of OCPs and PCBs in feathers of bids in the 1990s were generally below the thresholds reported to affect reproduction.  相似文献   
247.

Groundwater resources are the only source of water in many arid and semi-arid regions. It is important to manage these resources to have a sustainable development. However, there are many factors influencing the accuracy of the results in groundwater modeling. In this research, the uncertainty of two important groundwater model parameters (hydraulic conductivity and specific yield) were considered as the main sources of uncertainty in estimating water level in an unconfined aquifer, in Iran. For this purpose, a simple method called Rosenblueth Point Estimate Method (RPEM) was used to assess groundwater modeling parametric uncertainty, and its performance was compared with Monte Carlo method as a very complicated and time-consuming method. According to calibrated values of hydraulic conductivity and specific yield, several uncertainty intervals were considered to analyze uncertainty. The results showed that the optimum interval for hydraulic conductivity was 40% increase–30% decrease of the calibrated values in both Monte Carlo and RPEM methods. This interval for specific yield was 200% increase–90% decrease of the calibrated values. RPEM showed better performance using the evaluating indices in comparison with Monte Carlo method for both hydraulic conductivity and specific yield with 43% and 17% higher index values, respectively. These results can be used in groundwater management and future prediction of groundwater level.

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248.
Environmental Science and Pollution Research - Chromium (Cr), being a persistent toxic heavy metal, triggered the retardation of plant’s metabolic processes by initiating changes in...  相似文献   
249.
Environmental Science and Pollution Research - This study aims to determine the moderating role of IT capability between green intellectual capital (GIC) and business sustainability in...  相似文献   
250.
Environmental Science and Pollution Research - Greenhouse hydroponic experiments were carried out using three different heavy metal accumulation tobacco genotypes to evaluate how different...  相似文献   
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