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1.
Journal of Material Cycles and Waste Management - Effective municipal solid waste collection and disposal system is not possible without reliable solid waste generation and classification data...  相似文献   
2.
Journal of Polymers and the Environment - Plastics are widely used by the community, especially as food packaging. In general, plastic raw materials are polymers which have advantages including...  相似文献   
3.
Water quality indices (WQIs) have been developed to assess the suitability of water for a variety of uses. These indices reflect the status of water quality in lakes, streams, rivers, and reservoirs. The concept of WQIs is based on a comparison of the concentration of contaminants with the respective environmental standards. The number, frequency, and magnitude by which the environmental standards for specific variables are not met in a given time period are reflected in WQIs. Further, the water quality trend analysis predicts the behavior of the water quality parameters and overall water quality in the time domain. In this paper, the concept of WQI was applied to three selected watersheds of Atlantic region: the Mersey River, the Point Wolfe River, and the Dunk River sites. To have robust study, two different water quality indices are used: Canadian Water Quality Index (CWQI), and British Columbia Water Quality Index (BWQI). The complete study was conducted in two steps. The first step was to organize and process the data into a format compatible with WQI analysis. After processing the input data, the WQI was calculated. The second step outlined in the paper discusses detailed trend analysis using linear and quadratic models for all the three sites. As per the 25 years trend analysis, overall water quality for agriculture use observed an improving trend at all the three sites studied. Water quality for raw water used for drinking (prior to treatment) and aquatic uses has shown improving trend at Point Wolfe River. It is further observed that pH, SO4, and NO3 concentrations are improving at Dunk River, Mersey River, and Point Wolfe River sites. To ascertain the reliability and significance of the trend analysis, a detailed error analysis and parametric significance tests were also conducted It was observed that for most of the sites and water uses quadratic trend models were a better fit than the linear models.  相似文献   
4.
The Linggi river drainage basin in Negeri Sembilan, Malaysia supplies water to the whole of Port Dickson district and meets 50% of the Seremban district needs. The Linggi River, the main tributary, passes through the highly urbanised and densely populated Seremban district while the water treatment plant is located 16 km downstream. In 1979 the USEPA declared the river unsuitable as a source of raw water whereas the WHO classified it as being heavily polluted requiring more extensive and effective treatment. In order to meet the WHO drinking water standards, an ozonation system was installed in the conventional water treatment plant. The objective of ozonation is for the control and removal of organic micropollutants and other deleterious matters. This study investigated the concentrations and distribution of organic micropollutants, heavy metals, and bacteriological counts in water samples collected from within the catchment and the treated water. The effectiveness of the ozonation system was also studied. The total level of phenolic water pollutants in the catchment was generally found to be very much higher than the maximum recommended level of 2.0 µgl-1. The extensive treatment process carried out at the plant was very effective in reducing the levels of total phenols in the treated water to less than 1.0 µgl-1. However the process was not efficient enough to reduce the levels of some heavy metals as required by the standards, for examples Cd and Pb were still three times higher than the standards of 5µgl-1 and 0.05 mgl-1 respectively. For bacteriological study, coliform group of bacteria, Salmonella, faecal streptococci and injured coliform were monitored in the raw and treated water. The raw water contained coliforms about 1000 times higher than the required standard for raw ater, but after the secondary treatment by ozonation coliform bacteria were absent, however a small number of Salmonella was still present occasionally. The study also showed that restructuring of the district and relocating of some commercial activities along the river banks to other areas carried out over the last five years has improved the general quality of the river water.  相似文献   
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This study aimed to fabricate new and effective material for the efficiency of phosphate adsorption. Two types of adsorbent materials, the zirconium hydroxides embedded in pomegranate peel (Zr/Peel) and zirconium-lanthanum hydroxides embedded in pomegranate peel (Zr–La/Peel) were developed. Scanning electronic microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and x-ray diffraction (XRD) were evaluated to give insight into the physicochemical properties of these adsorbents. Zr–La/Peel exceeded the adsorption efficiency of Zr/Peel adsorbents in batch adsorption experiments at the same pH level. The peel as a host can strive to have a strong “shielding effect” to increase the steadiness of the entrenched Zr and La elements. La and Zr are hydroxide metals that emit many hydrogen ions during the hydrolysis reaction, which contribute to protonation and electrostatic attraction. The highest adsorption capacity of La–Zr/Peel for phosphate was calculated to be 40.21 mg/g, and pseudo second-order equation is very well fitted for kinetic adsorption. Phosphate adsorption efficiency was reduced by an increase of pH. With the background of coexisting Cl?, little effect on adsorption efficiency was observed, while adsorption capacities were reduced by almost 20–30% with the coexistence of SO42?, NO3? and humic acid (HA).  相似文献   
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8.
This paper shows that spent lubricating oils from automobile engines generate carboxylic acids on environmental exposure. Samples of exposed oils, isolated from polluted river water and shore muds obtained from various locations, showed a direct proportionality between carboxylic acid content and time of exposure. Carboxylic acids were isolated by solvent extraction and studied by infrared spectroscopy.  相似文献   
9.
In this study, a survey instrument was developed to measure safety climate. A review of the scientific literature as well as consultation with an expert panel was used to determine the survey's dimensions. Next, the survey was administered, first as a pilot study (n = 15) and then as a full scale study (n = 229), to employees of the City of Cincinnati Department of Public Works. The psychometric integrity of the survey was assessed according to validity, reliability and utility criteria. Results are presented and discussed.  相似文献   
10.
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