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331.
Environmental Science and Pollution Research - Breast and colon carcinomas are two types of common cancers which lead to cancer-related deaths. Due to their cytotoxic potential against cancer...  相似文献   
332.
Environmental Science and Pollution Research - This study provides insight into the decolorization strategy for crude glycerol obtained from biodiesel production using waste cooking oil as raw...  相似文献   
333.
Environmental Science and Pollution Research - The risks of environmental exposures of quantum dot (QD) nanoparticles are increasing, but these risks are difficult to assess because fundamental...  相似文献   
334.
The use of waters of impaired quality has been suggested as a means to expand available water resources supply for water‐limited communities. An ongoing concern is the safety of supplies that use wastewater because of the potential for introduction of emerging contaminants such as pharmaceuticals into drinking water supplies. Prior research into contaminants of emerging concerns (CECs) have included a variety of methods, but the only consistent removal is with reverse osmosis (RO) membranes, ultraviolet light (UV), and advanced oxidation processes (AOP). However, few of these prior studies have measurable quantities of these contaminants in the influent wastewater, so determining actual removal percentages is difficult. This project was designed to evaluate the removal of CECs to verify that a 3‐log removal of common constituents was realized. Spike testing was used to compare to prior research and to evaluate whether the project costs were competitive with other forms of reuse or other water supplies. The combination of RO/UV/AOP was effective at obtaining a 3‐log removal of CECs, but the RO and UV/AOP processes alone were not capable of removing all substances. However, despite the extensive treatment, the proposed process was both competitive cost‐wise and met the water quality goals.  相似文献   
335.
Cities in the Kurdistan region in Iraq – particularly, the capital city of Hewlair (Erbil) – are facing environmental problems such as water, air and noise pollution. Political instability, ethnic tensions, politically motivated decisions, wars and economic sanctions, consumerism, lack of sufficient funds, and tension between the federal and regional governments due to power and wealth sharing are major contributors to the environmental problems; this paper will depict and analyse these. Although these problems are causing serious health issues for the inhabitants and sometimes death, the authorities are unable to solve them. The paper sheds light on the causes and effects of the environmental problems and also draws conclusions and makes suggestions.  相似文献   
336.
Five previously developed temperature-distribution models are compared using data from actual thermal energy storage (TES) systems, and the advantages and disadvantages of each model are identified. These models are used for evaluating the energy and exergy in a TES. Furthermore, the accuracy and simplicity of the temperature-distribution models (Linear, Stepped, Continuous-linear, Three-zone and General-linear) are compared in order to determine which model has the greatest accuracy and simplicity regarding computational effort, while providing physical understanding. After fitting the models to temperature data for 35 stratified TES samples, it was observed that some models are easy to use but relatively inaccurate, while others are relatively accurate but complicated to use. As a trade-off, the Three-zone model provides physical understanding, yields acceptable accuracy and is relatively simple to use, especially in computing the parameters needed for energy and exergy assessments of stratified TESs.  相似文献   
337.
Conventional measures of economic output, national income and wealth highly underestimate the value and contribution of natural resources to economic welfare. This paper makes estimates of the asset values and flow benefits of non-traded goods and services from forests and woodland resources in South Africa. Four benefit categories were included, namely direct consumptive use values (timber and non-timber products), non-consumptive use values (recreation for example), indirect use values (environmental services such as carbon sequestration, watershed protection, etc.), and non-use values (based on contingent valuation by tourists). Asset values were calculated knowing the change in physical stocks and the relevant prices. In South Africa, the increase in assets was equivalent to 1.1% of gross domestic product (GDP) (forests were improving, but fynbos deteriorating), and the flow benefits were equivalent to 0.8% of GDP. These are large magnitudes.  相似文献   
338.
The degradation of some organophosphorus pesticides (OPPs) in the presence of metal ions was studied by 31P-NMR spectroscopy. Both 31P-NMR and gas chromatography/mass spectroscopy results were used in order to determine the nature of metabolites formed after degradation. The degraded organophosphorus pesticide were investigated for chlorpyrifos and phoxim in the presence of several metal ions including Hg2+, Cu2+, Cd2+, Ni2+, Pb2+, and Ag+. 31P-NMR results indicated Ag+ and Hg2+ ion promoted degradation of OPPs and other metal ions formed complex with OPPs and cannot degrade OPPs. We found that the degradation of chlorpyrifos and phoxim with Ag+ or Hg2+ led to the formation of O,O-diethyl-O-methyl phosphorothionate, (C2H5O)2(CH3O)PS, at metal ion/pesticide mole ratios ≤1.0 and completely decomposed at a higher mole ratio of 10. Finally, the method was successfully applied to the degradation study of a number of technical and formulated pesticides in the presence of Ag+ ion at a metal ion/pesticide mole ratio of 10.  相似文献   
339.
Flood spreading is a suitable strategy for controlling and benefiting from floods. Selecting suitable areas for flood spreading and directing the floodwater into permeable formations are amongst the most effective strategies in flood spreading projects. Having combined geographic information systems (GIS) and multi-criteria decision analysis approaches, the present study sought to locate the most suitable areas for flood spreading operation in the Garabaygan Basin of Iran. To this end, the data layers relating to the eight effective factors were prepared in GIS environment. This stage was followed by elimination of the exclusionary areas for flood spreading while determining the potentially suitable ones. Having closely examined the potentially suitable areas using the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) II and analytic hierarchy process (AHP) methods, the land suitability map for flood spreading was produced. The PROMETHEE II and AHP were used for ranking all the alternatives and weighting the criteria involved, respectively. The results of the study showed that most suitable areas for the artificial groundwater recharge are located in Quaternary Qg and Qgsc geologic units and in geomorphological units of pediment and Alluvial fans with slopes not exceeding 3 %. Furthermore, significant correspondence between the produced map and the control areas, where the flood spreading projects were successfully performed, provided further evidence for the acceptable efficiency of the integrated PROMETHEE II-AHP method in locating suitable flood spreading areas.  相似文献   
340.
An accurate and reproducible method for the analysis of flurazepam hydrochloride in pharmaceutical preparations has been described. A simple and rapid isocratic HPLC elution method was employed which requires about 15 minutes to be performed. The percentage mean recovery of flurazepam hydrochloride in Dalmane capsules was found to be 100.67% + 1.23% of the declared amount  相似文献   
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