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11.
Ahmed Amani Shawki Ibrahim Dalia Anas Hassan Tarek Hamdy Abd-El-Azem Wael Galal 《Environmental science and pollution research international》2022,29(23):33901-33908
Environmental Science and Pollution Research - Cleaning products are mixtures of many chemical ingredients that are known to contain sensitizers, disinfectants, and fragrances, as well as strong... 相似文献
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Environmental Modeling & Assessment - Widening income inequality and environmental degradation are two of the most important problems that threat the sustainable development. For that, this... 相似文献
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Methane emissions, concentrations, and oxidation were measured on eleven MSW landfills in eleven states spanning from California to Pennsylvania during the three year study. The flux measurements were performed using a static chamber technique. Initial concentration samples were collected immediately after placement of the flux chamber. Oxidation of the emitted methane was evaluated using stable isotope techniques. When reporting overall surface emissions and percent oxidation for a landfill cover, central tendencies are typically used to report “averages” of the collected data. The objective of this study was to determine the best way to determine and report central tendencies. Results showed that 89% of the data sets of collected surface flux have lognormal distributions, 83% of the surface concentration data sets are also lognormal. Sixty seven percent (67%) of the isotope measured percent oxidation data sets are normally distributed. The distribution of data for all eleven landfills provides insight of the central tendencies of emissions, concentrations, and percent oxidation. When reporting the “average” measurement for both flux and concentration data collected at the surface of a landfill, statistical analyses provided insight supporting the use of the geometric mean. But the arithmetic mean can accurately represent the percent oxidation, as measured with the stable isotope technique. We examined correlations between surface CH4 emissions and surface air CH4 concentrations. Correlation of the concentration and flux values using the geometric mean proved to be a good fit (R2 = 0.86), indicating that surface scans are a good way of identifying locations of high emissions. 相似文献
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Minimization of the formation of disinfection by-products 总被引:1,自引:0,他引:1
The drinking water industry is required to minimize DBPs levels while ensuring adequate disinfection. In this study, efficient and appropriate treatment scheme for the reduction of disinfection by-product (DBPs) formation in drinking water containing natural organic matter has been established. This was carried out by the investigation of different treatment schemes consisting of enhanced coagulation, sedimentation, disinfection by using chlorine dioxide/ozone, filtration by sand filter, or granular activated carbon (GAC). Bench scale treatment schemes were applied on actual samples from different selected sites to identify the best conditions for the treatment of water. Samples were collected from effluent of each step in the treatment train in order to analyze pH, UV absorbance at 254 nm (UVA254), specific UV absorbance at 254 nm (SUVA254), dissolved organic carbon (DOC), haloacetic acids (HAAs) and trihalomethanes (THMs). The obtained results indicated that using pre-ozonation/enhanced coagulation/activated carbon filtration treatment train appears to be the most effective method for reducing DBPs precursors in drinking water treatment. 相似文献
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The Distribution and Sources of Polycyclic Aromatic Hydrocarbons in Surface Sediments Along the Egyptian Mediterranean Coast 总被引:2,自引:0,他引:2
El Nemr A Said TO Khaled A El-Sikaily A Abd-Allah AM 《Environmental monitoring and assessment》2007,124(1-3):343-359
Coastal marine sediment samples were collected from 31 sampling stations along the Egyptian Mediterranean Sea coast. All sediment
samples were analyzed to determine aliphatic and polycyclic aromatic hydrocarbons (PAHs) as well as total organic carbon (TOC)
contents and grain size analysis. Total concentrations of 16 EPA-PAHs in the sediments were varied from 88 to 6338 ng g−1 with an average value of 154 ng g−1 (dry weight). However, the concentrations of total aliphatic were varied from 1.3 to 69.9 ng g−1 with an average value of 15.6 ng g−1 (dry weight). The highest contents of PAHs were found in the Eastern harbor (6338 ng g−1), Manzala (5206 ng g−1) and El-Jamil East (4895 ng g−1) locations. Good correlations observed between a certain numbers of PAH concentrations allowed to identify its origin. The
average total organic carbon (TOC) percent was varied from 0.91 to 4.54%. Higher concentration of total pyrolytic hydrocarbons
(∑COMB) than total fossil hydrocarbons (∑PHE) declared that atmospheric fall-out is the significant source of PAHs to marine
sediments of the Egyptian Mediterranean coast. The selected marked compounds, a principal component analysis (PCA) and special
PAHs compound ratios (phenanthrene/anthracene vs fluoranthene/pyrene; ∑COMB/∑EPA-PAHs) suggest the pyrogenic origins, especially
traffic exhausts, are the dominant sources of PAHs in most locations. Interferences of rather petrogenic and pyrolytic PAH
contaminations were noticed in the harbors due to petroleum products deliveries and fuel combustion emissions from the ships
staying alongside the quays. 相似文献
16.
Antoine Ayoub 《Natural resources forum》1990,14(2):163-167
Current surplus oil production capacity had its origins in the price increases of the 1970s. Those increases encouraged both energy conservation and the entry of new producers. Recent increases in oil demand reflect the belief among energy users that in real terms in the long term, prices will be stable. There is good reason to believe that this will be so, even at the current rate of increase it will be 15 years before demand matches current capacity. Given that situation it is difficult to see OPEC following any other pricing policy than the one currently in place. In the meantime market prices will further encourage vertical integration. 相似文献
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Hussien Ahmed Abbas Rabab Ahmed Nasr Rose-Noëlle Vannier Tarek Samir Jamil 《环境科学学报(英文版)》2022,34(2):331-342
Nanosized Ba1- xBixFe1-xCuxO3(12–50 nm) with x values of 0, 0.01, 0.05, and 0.1 system was prepared using the Pechini method. Structural, morphological, surface and optical characterizations were performed for the prepared samples. Cubic phase was the predominant phase for the undoped BaFeO3 and Bi and Cu co-doped BaFeO3 samples. Minor phases of monoclinic Ba2Fe2O5, orthorhombic BaFe 相似文献
19.
Shahr El-Din Ahmed M. Monir Tarek Borai Emad H. 《Journal of Polymers and the Environment》2021,29(11):3721-3731
Journal of Polymers and the Environment - Rare earth elements (REEs) play a critical role in the applications of advanced materials. In this respect, an eco-friendly calcium/alginate-graphene oxide... 相似文献
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El-Din Ahmed Mohamed Shahr Monir Tarek Sayed Moubarak A. 《Environmental science and pollution research international》2019,26(25):25550-25563
Environmental Science and Pollution Research - For human health and safety, it is of great importance to develop innovative materials with a vast capacity for powerful removal of radioactive ions... 相似文献