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291.
Journal of Material Cycles and Waste Management - The extraction of unsustainable natural resources like sand and topsoil for construction is disturbing ecological balance, affecting local...  相似文献   
292.
293.
Environmental Science and Pollution Research - Azolla is a group of aquatic floating plants that can achieve very high growth rates compared to other aquatic macrophytes, with a doubling time of...  相似文献   
294.
Environmental Science and Pollution Research - The ongoing COVID-19 outbreak, initially identified in Wuhan, China, has impacted people all over the globe and new variants of concern continue to...  相似文献   
295.
Environmental Science and Pollution Research - The idea of sustainable development and green supply chain management is considered at the underlying stage in the research and academic fields,...  相似文献   
296.
A large variety of ornamental and decorative items are manufactured from bone waste by various unorganized sectors in India. An initial survey indicated that workers were exposed at various phases of final product. The subjects (12 industrial units) were tested for total suspended particulate matter (TSPM), particulate matter <10  $\upmu $ m (PM10), and particulate matter <2.5  $\upmu $ m (PM2.5). Prevalent levels of TSPM ranged between 2.90 and 5.89 mg m???3. Respirable fractions of occupational dust as PM10 and PM2.5 were found in the range of 0.30?C2.08 and 0.26?C0.50 mg m???3, respectively. Cytotoxicity study was conducted using hemolysis as a sensitive marker. In an in vitro study, rat RBCs were exposed to the concentration of 25?C1,000  $\upmu $ g/ml for 15?C120 min. A considerable variation was observed in the hemolytic activity of samples collected from different areas. At 500  $\upmu $ g/ml concentration, the hemolytic activity (12 h) was found to be in the range of 18?C25%. Due to limitation in sample mass of respirable fractions, only one concentration (100  $\upmu $ g/ml/2 h) was used for comparative study on hemolysis of RBCs caused by PM10 and PM2.5. Interestingly, the hemolytic activity was more at PM2.5 than PM10 and TSPM. These results suggest that the respirable particles are capable of reaching deep into the respiratory system. The finding is significant notably when there are no standards available in occupationally exposed populations. This is the first such study. Data could be of importance to policy makers and regulators.  相似文献   
297.
Ahmad I  Pacheco M  Santos MA 《Chemosphere》2006,65(6):952-962
Pateira de Fermentelos (PF) is a natural freshwater wetland in the central region of Portugal. In the last decade, the introduction of agricultural chemicals, heavy metals, domestic wastes, as well as eutrophication and incorrect utility of resources resulted in an increased water pollution. The present research work was carried out to check the various oxidative stress biomarker responses in European eel (Anguilla anguilla L.) gill, kidney and liver due to this complex water pollution. Eels were caged and plunged at five different PF sites (A-E) for 48h. A reference site (R) was also selected at the river spring where no industrial contamination should be detected. Lipid peroxidation (LPO), catalase (CAT), glutathione peroxidase (GPX), glutathione S-transferase (GST) and reduced glutathione (GSH) were the oxidative stress biomarkers studied. In gill, site A exposure induced a significant GST activity increase and site B exposure induced CAT activity increase when compared to R. Site C exposure showed a significant CAT and GPX activity increase. Data concerning site D exposure were not determined due to cage disappearance. Site E exposure displayed a significant CAT and GST activity increase. In kidney, site A exposure induced a significant CAT and GPX decrease as well as a GST increase. Site B exposure showed a significant decrease in GPX activity and GSH content. However, site C exposure demonstrated a significant increase in CAT and a decrease in GPX. Site E exposure showed a significant decrease in GPX and increase in GST. In liver, site A exposure showed a significant GST activity decrease as well as GSH content increase. Site B exposure showed a significant CAT, GST and LPO decrease. Site C exposure showed only GST activity decrease, while site E exposure induced a significant increase in GPX. These investigation findings provide a rational use of oxidative stress biomarkers in freshwater ecosystem pollution biomonitoring using caged fish, and the first attempt reported in Portugal as a study of this particular watercourse under the previous conditions. The presence of pollutants in the PF water was denunciated even without a clear relation to the main pollution source distance. The organ specificity was evident for each parameter but without a clear pattern.  相似文献   
298.
Hydrogen management is a problem of increasing importance: hydrogen consumption of refineries is rising sharply with additional capacities of hydrocracking and hydrotreating units in order to comply with cleaner fuel specifications. Product Specifications for transportation fuels are becoming increasingly stringent to ensure production of environmentally more benign fuels. Hydrogen management techniques currently do not account for varying operating conditions of hydrogen consuming processes and assume constant operating conditions. A novel approach is developed for the design of flexible hydrogen networks that can remain optimally operable under multiple periods of operation. The proposed methodology for multi-period design of hydrogen networks can take into account pressure differences, maximum capacity of existing equipment, and optimal placement of new equipment such as compressors.  相似文献   
299.
This study was carried out to assess the radiological impact of Syrian phosphogypsum (PG) piles in the compartments of the surrounding ecosystem. Estimating the distribution of naturally occurring radionuclides (i.e. (226)Ra, (238)U, (232)Th, (210)Po and (210)Pb) in the raw materials, product and by-product of the Syrian phosphate fertilizer industry was essential. The data revealed that the concentrations of the radionuclides were enhanced in the treated phosphate ore. In PG, (226)Ra content had a mean activity of 318 Bq kg(-1). The uranium content in PG was low, ca. 33 Bq kg(-1), because uranium remained in the phosphoric acid produced. Over 80% of (232)Th, (210)Po and (210)Pb present partitioned in PG. The presence of PG piles did not increase significantly the concentration of (222)Rn or gamma rays exposure dose in the area studied. The annual effective dose was only 0.082 mSv y(-1). The geometric mean of total suspended air particulates (TSP) ca. 85 μg m(-3). The activity concentration of the radionuclides in filtrates and runoff waters were below the detection limits (ca. 0.15 mBq L(-1) for (238)U, 0.1 mBq L(-1) for (232)Th and 0.18 mBq L(-1) for both of (210)Po and (210)Pb); the concentration of the radionuclides in ground water samples and Qattina Lake were less than the permissible limits set for drinking water by the World Health Organisation, WHO, (10, 1 and 0.1 Bq L(-1) for (238)U, (232)Th and both of (210)Po and (210)Pb, respectively). Eastern sites soil samples of PG piles recorded the highest activity concentrations, i.e. 26, 33, 28, 61 and 40 Bq kg(-1) for (226)Ra, (238)U, (232)Th, (210)Po and (210)Pb, respectively, due to the prevailing western and north-western wind in the area, but remained within the natural levels reported in Syrian soil (13-32 Bq kg(-1) for (226)Ra, 24.9-62.2 Bq kg(-1) for (238)U and 10-32 Bq kg(-1) for (232)Th). The impact of PG piles on plants varied upon the plant species. Higher concentrations of the radionuclides were recorded for grass in comparison to broad-leaved plants. Among the species that grow naturally on PG piles, Inula, Ecballium and Polygonium may be radionuclides accumulators. A determined effort is needed at a national level to achieve a common and coherent approach to regulate PG piles or to consider it a resource material rather than waste or residue.  相似文献   
300.
The present work deals with the assessment of bacteriological contamination along with some physico-chemical parameters of water samples from Lahore canal. ANOVA showed that the observed p values of log-transformed viable plate counts, total suspended solids, turbidity, and biological oxygen demand are 0.000, 0.000, 0.000, and 0.000, respectively, which are <0.05, while the p value of total coliforms, total fecal coliforms, and Escherichia coli are 0.728, 0.827, and 0.081, respectively which are >0.05. Significant correlation was observed between log-transformed viable plate counts (CFU), biological oxygen demand, total suspended solids, and turbidity. Further regression analysis revealed that simple line regression model is fit for log-transformed viable plate counts and total suspended solids, log-transformed viable plate counts and turbidity, turbidity and total suspended solids, biological oxygen demand and total suspended solids, biological oxygen demand and log-transformed viable plate counts, and biological oxygen demand and turbidity.  相似文献   
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