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31.
Complex industrial discharges pose certain risks to the ecosystem. This study was aimed at identifying acute and sub-chronic toxicological effects of the textile industry wastewater. The textile wastewater was evaluated for the metals and organic pollutants by atomic absorption spectrophotometer and GC-MS respectively. In vitro genotoxicity and mutagenicity were assessed by Comet assay in peripheral lymphocytes isolated from Ovis aries and Ames test in Salmonella typhimurium strains TA-100 and 102 respectively. Physiological and behavioral changes along with systemic toxicity were determined in Rattus norvegicus albinus following acute and sub-chronic exposure. High amount of heavy metals such as Cr, Pb, Hg, As, and Cd were detected in textile wastewater. Organic pollutants such as 25-deacetoxy cucurbitacin-b, E-14-Hexadecenal, 11-Tricosene, and phthalates were also found. In vitro genotoxicity assessment in lymphocytes showed statistically significant DNA damaging potential of textile wastewater. Textile wastewater also showed significantly higher (p? 0.05) mutagenic potential in Salmonella TA-100 and TA-102 strains than sodium azide and 2-amino anthracycline. Acute exposure of textile wastewater to Rattus norvegicus was associated with several physiological changes and behavioral symptoms. Sub-chronic exposure of textile wastewater in Rattus norvegicus instigated the degeneration and necrosis of epithelial cells in renal tubules, hydropic degeneration and necrosis of hepatocytes, peri-bronchiolar infiltration and emphysema of the alveoli, and the degradation of myocardial cells. This study concludes that the textile wastewater may cause genotoxicity and mutagenicity, result in physiological and behavioral changes upon acute exposure, and inflict various pathological lesions upon sub-chronic exposure.  相似文献   
32.
In this study water soluble sodium carboxymethyl cellulose (CMC) was blended with high density polyethylene (HDPE) by peroxide-initiated melt compounding technique. The compatibility of the blended polymers were carried out by silane crosslinking agent. A series of blends were prepared by varying the CMC contents up to a maximum of 50 phr. The physical properties of non-crosslinked and crosslinked blends were investigated in detail. FTIR analysis of crosslinked blend confirmed the presence of Si–O–Si and Si–O–C absorption peaks at 1050 and 1159 cm?1. Thermal stability of crosslinked blends improved as compared to its non-crosslinked congener. Rheological study of crosslinked blends illustrated high complex viscosity and dynamic shear storage modulus. The tensile strength of virgin polyethylene was 8.1 MPa whereas the maximum tensile strength of 19.6 MPa was observed in crosslinked blend. Similarly lower deformation was observed in crosslinked blends under static load. Scanning electron microscopy of crosslinked formulations also showed strong adhesion between the polymers interface. The compatibility of HDPE and CMC is attributed to both free radical and condensation reactions.  相似文献   
33.
Several factors influence air pollution, but effect of land uses is pivotal and has direct consequences on growth and development of a city. In order to assess consequent effects of land uses on air pollution, it is important to transform a set of variables into significant components by using principal component analysis. These components help to develop an effective model between air pollution and land uses by application of regression analysis. Lahore, titled as “Paris of the East,” has some featured commonalities with Paris and was jointly selected for research to adopt common policies and measures to combat air pollution. A two-step cluster analysis has been applied to testify resemblance of Paris to towns of Lahore as a cluster. This paper is trying to develop a calibrated model which helps to estimate about air pollution at a significant level with only one independent variable. Furthermore, it helps to control air pollution through sensitization of land uses in Lahore.  相似文献   
34.
The objective of the study is to examine the relationship between air pollution, fossil fuel energy consumption, water resources, and natural resource rents in the panel of selected Asia-Pacific countries, over a period of 1975–2012. The study includes number of variables in the model for robust analysis. The results of cross-sectional analysis show that there is a significant relationship between air pollution, energy consumption, and water productivity in the individual countries of Asia-Pacific. However, the results of each country vary according to the time invariant shocks. For this purpose, the study employed the panel least square technique which includes the panel least square regression, panel fixed effect regression, and panel two-stage least square regression. In general, all the panel tests indicate that there is a significant and positive relationship between air pollution, energy consumption, and water resources in the region. The fossil fuel energy consumption has a major dominating impact on the changes in the air pollution in the region.  相似文献   
35.
The present study was conducted to determine the effects of microwave oven frying on production of four, light polycyclic aromatic hydrocarbons (PAH) anthracene, fluorene, phenathrene, and pyrene in four tissues heart, liver, neck, and wings of Aseel chickens. The microwave oven-fried samples of tissues along with respective control after appropriate preparation were analyzed using high-performance liquid chromatography. These PAH were identified by comparing retention time of the unknown with known ones and concentration was calculated. Data showed that among the four chicken tissues, the neck contained the maximum level (0.079 mg/kg) of anthracene while wings contained the minimum (0.006 mg/kg). Similarly, in case of flourene, the fried heart showed greater percentage increase (225.04%) while wings showed 16.18% fluorene compared with other two organs, while phenanthrene and pyrene were maximal in wings at 0.249 mg/kg and 0.094 mg/kg, respectively. Results demonstrate that high-temperature treatment such as microwave oven frying of chicken meat might be responsible to generate these toxicants. Further study is to determine the production of other PAH under the different barbecuing conditions using various meat varieties.  相似文献   
36.
Environmental Science and Pollution Research - In the last few decades, wind energy has become a significant source of the renewable energy system, and it is essential to use wind energy for...  相似文献   
37.
The pyrolysis and chlorination of petroleum coke in a NaCl‐KCl melt results in the production of CCl4 and C6Cl6. Polychlorinated dibenzo‐p‐dioxins (PCDDs) are produced from the air oxidation and chlorination of coal using HCl or Cl2. Smoking of tobacco containing 36Cle provides CH3 36Cl.

At 350°C, the rateof aromatization of 1,3‐cyclohexadiene is negligible as compared to that of 1,4‐cyclohexadiene. The aromatization of the latter diene proceeds through the molecular elimination of hydrogen; while that of 1,3‐cyclohexadiene expecially at higher pressure (10–90 Torr) and at 362–421 °C involves free radical chain mechanism.  相似文献   
38.
The Middle Mississippi River (MMR) and lower Missouri River (MOR) provide critical navigation waterways, ecological habitat, and flood conveyance. They are also directly linked to processes affecting geomorphic and ecological conditions in the lower MR and Delta. For this study, a method was developed to measure suspended‐sediment concentration (SSC) and turbidity along the MMR and the lower MOR using Landsat imagery. Data from nine United States Geological Survey water‐quality monitoring stations were used to create a model‐development dataset and a model‐validation dataset. Concurrent gaging data were identified for available Landsat images to generate the datasets. Surface‐reflectance filters were developed to eliminate images with cirrus cloud coverage or vessel traffic. Using the filtered model‐development dataset, unique reflectance‐SSC and reflectance‐turbidity models were developed for three Landsat sensors: Landsat 8 Operational Land Imager, Landsat 7 Enhanced Thematic Mapper Plus, and Landsat 4–5 Thematic Mapper. Coefficient of determination values for the models ranged from 0.72 to 0.88 for the model‐development dataset. The model‐validation dataset was used to evaluate the performance of the models and had coefficient of determination values ranging from 0.62 to 0.79.  相似文献   
39.
Both laboratory and commercial preparations of humic substances (HSs) such as fulvic acids and humic acids along with HC1‐HF preparation of Manitoba peat soil organic matter were characterized using Fourier Transformation (FT) proton (1H) and carbon‐13 (13C) nuclear magnetic resonance (NMR) spectroscopy. All the samples were dissolved in a solution of 0.4 N NaOD in D2O. In the case of ‘H‐NMR spectroscopy, all the investigated humic samples displayed resonance absorption peaks in the region of 1–4 ppm indicating the likely presence of aliphatic protons in the preparations. However, with the exception of one fulvic acid preparation (extracted from Manitoba Carrol clay‐loam soil with 0.5 N NaOH), 1H‐NMR spectra of all other samples provided evidence for strong aromatic character. The aliphatic and aromatic characteristics of such samples of HSs were further confirmed with the aid of 13C‐NMR spectra.  相似文献   
40.

This study is based on self-reported information collected from selected farmers of Vehari District, Punjab, Pakistan, to determine their technical knowledge and awareness about pesticide use and associated environmental and health risks. Moreover, soil contamination by routinely used persistent organochlorine pesticide, endosulfan, was also evaluated. Survey data revealed very low literacy rate (on an average 9th grade education) and technical knowledge (almost missing) of the farmers in Vehari District. The farmers are unable to fully read and understand the instructions about the use of pesticide marked on the containers. They are not fully aware of pesticide persistence and toxicity (73%), unable to identify cotton pests and diseases (86%), and do not know which crop to grow in cotton adjacent fields (100%). Data also revealed that the farmers (100%) do not follow safety measure during pesticide application and are unaware of pesticide toxicity symptoms in human as well as the basic first-aid practices (89%).

Poor literacy rate and lack of technical knowledge of farmers in Vehari regarding pesticide use and handling are posing serious environmental and health risks among the local inhabitants, particularly among farmers. Soil analysis results showed that concentration of α- and β-endosulfan ranged from 0–14 to 0–14.64 μg/mg, respectively. Principal component analysis showed that soil organic matter is the key soil parameter controlling the occurrence and fate of endosulfan under sandy loam soil conditions of Vehari District. There is a serious need of improving technical and environmental knowledge of farmer about pesticide risks on human health in the studied area, in particular, and the entire country in general. Findings are of great use for policymaking in Pakistan to minimize pesticide risks in Pakistan.

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