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Crude oil (from oil terminal) and raw phosphate (from phosphate port) pollution are responsible for the lowered health conditions of coral reefs at their vicinity in the Jordanian coast of the Gulf of Aqaba. Both in situ incubations and ex situ laboratory exposure experiments were used to study the effects of those pollutants on corals, by using molecular and biochemical biomarkers in the coral Stylophora pistillata. For ex situ part of the experiment, crude oil and raw phosphate were added to a final concentration of 500?ppm for both pollutants. The DNA damage was assessed by Comet assay, while biochemical stress markers were reassessed by lipid peroxidation (LPO) test. Although the corals looked healthy from outside, the use of stress biomarkers indicated that they are under high pressure at the cellular level. The corals incubated with oil and phosphate had more DNA damage and LPO in comparison with the control samples. The results obtained suggest that the use of stress biomarkers can be used as important prognostic tools for examining the sub-lethal stress on corals before their death.  相似文献   
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Environmental Science and Pollution Research - This study was concerned with the temporal analysis of benzene, toluene, ethylbenzene, xylenes (BTEXs), and ozone in Rochester, New York, between 2012...  相似文献   
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Environmental Science and Pollution Research - Antioxidant enzymes such as glutathione S-transferases (GSTs) and cytochromes P450 (CYPs) are involved in the metabolism and detoxification of...  相似文献   
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Valuable chemicals can be separated from agricultural residues by chemical or thermochemical processes. The application of pyrolysis has already been demonstrated as an efficient means to produce a liquid with a high concentration of desired product. The objective of this study was to apply an insect and microorganism bioassay-guided approach to separate and isolate pesticidal compounds from bio-oil produced through biomass pyrolysis. Tobacco leaf (Nicotianata bacum), tomato plant (Solanum lycopersicum), and spent coffee (Coffea arabica) grounds were pyrolyzed at 10°C/min from ambient to 565°C using the mechanically fluidized reactor (MFR). With one-dimensional (1D) MFR pyrolysis, the composition of the product vapors varied as the reactor temperature was raised allowing for the selection of the temperature range that corresponds to vapors with a high concentration of pesticidal properties. Further product separation was performed in a fractional condensation train, or 2D MFR pyrolysis, thus allowing for the separation of vapor components according to their condensation temperature. The 300–400°C tobacco and tomato bio-oil cuts from the 1D MFR showed the highest insecticidal and anti-microbial activity compared to the other bio-oil cuts. The 300–350 and 350–400°C bio-oil cuts produced by 2D MFR had the highest insecticidal activity when the bio-oil was collected from the 210°C condenser. The tobacco and tomato bio-oil had similar insecticidal activity (LC50 of 2.1 and 2.2 mg/mL) when the bio-oil was collected in the 210°C condenser from the 300–350°C reactor temperature gases. The 2D MFR does concentrate the pesticidal products compared to the 1D MFR and thus can reduce the need for further separation steps such as solvent extraction.  相似文献   
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Increasing environmental issues, economic and cultural differences, the regulatory framework and the great attention to social responsibility, have forced companies to face the challenge of sustainability. Thus, the adaption of a proper marketing strategy in order to achieve a sustainable competitive advantage in the market (specially export markets) has become an important principle in accepting companies. In this regard, this study is a systematic literature review, which investigated 102 published articles in international journals between 1964 and 2015. In the literature review, the main focus was on key issues such as sustainability, marketing strategies, financial and market export performance. In this article, at first, the concept of sustainability from different aspects was collected and described. Then, external factors, such as competitive intensity, public concern, regulations, technology, cultural/social, and economic, as well as internal factors, such as managers, employees, stakeholders, affecting sustainability, were studied. Finally, adaption of export marketing strategies in order to achieve sustainability export performance is discussed.  相似文献   
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In this research, probable arsenic contamination in drinking water in the city of Ardabil was studied in 163 samples during four seasons. In each season, sampling was carried out randomly in the study area. Results were analyzed statistically applying SPSS 19 software, and the data was also modeled by Arc GIS 10.1 software. The maximum permissible arsenic concentration in drinking water defined by the World Health Organization and Iranian national standard is 10 μg/L. Statistical analysis showed 75, 88, 47, and 69% of samples in autumn, winter, spring, and summer, respectively, had concentrations higher than the national standard. The mean concentrations of arsenic in autumn, winter, spring, and summer were 19.89, 15.9, 10.87, and 14.6 μg/L, respectively, and the overall average in all samples through the year was 15.32 μg/L. Although GIS outputs indicated that the concentration distribution profiles changed in four consecutive seasons, variance analysis of the results showed that statistically there is no significant difference in arsenic levels in four seasons.  相似文献   
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Iran is the second largest stockholder of construction stones with 10 % of world production ;and there are more than 4000 stone cutting and fabrication industries (SCFIs). In the processing of raw stones, a considerable part of stone is turned into waste. Generated wastes include excess parts of different stones and sludge. The present paper reviews the state of SCFIs waste management using multiple data sources including site, analysis of effluent and sludge samples, and conducting interviews with people who are involved in 286 SCFIs in Qom and Tabriz. The results revealed that currently almost 35 to 52.5 % of raw stones were converted to solid wastes depending on stone cutting and processing methods, type of stones and their quality, which seemed a high percentage. Also, the effluents between 0.8 and 2.8 m3 were generated per ton of processed stone. Based on the analysis of heavy metals with atomic absorption spectroscopy, sludge samples contained a considerable amount of Pb, Cu, Cr, and Cd. It was also found that the lack of specific recycling, reuse and disposal programs and suitable supervision has led to uncontrolled disposal of stone wastes and sludge in different areas. However, there are good opportunities for reuse and recycling of the SCFIs wastes.  相似文献   
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