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21.
In this paper, a fuzzy decision making methodology is proposed to find a socially optimal scenario for allocating effluent of wastewater treatment plants and urban and suburban runoffs to agricultural regions and recharging aquifers. The presented methodology named modified fuzzy social choice (MFSC) considers multi-stakeholder multi-criteria problems under uncertainties inherent in a decision making process utilizing a fuzzy ranking method and the fuzzy social choice (FSC) theory. A set of water and wastewater allocation scenarios are proposed for water quantity and quality management of the study area, while six main stakeholders with conflicting utilities and different negotiation powers are involved. The proposed methodology is applied to Tehran metropolitan area, the capital city of Iran with the population of about 8 million people, to examine its applicability and effectiveness. The results shows that using fuzzy multi-stakeholder multi-criteria decision making method considering equal and different negotiation powers can lead to different outcomes. Based on the results, the MFSC method, which considers a number of decision makers having different negotiation powers, degrees of importance of decision making criteria, and some important uncertainties, performs more promising in real water resources management problems. 相似文献
22.
Aung Thiri Shwesin Saboori Behnaz Rasoulinezhad Ehsan 《Environmental science and pollution research international》2017,24(25):20487-20501
Environmental Science and Pollution Research - This empirical study examines the short- and long-run relationship between GDP as an economic growth indicator and CO2 emissions as an environmental... 相似文献
23.
Roozbeh Mirza Mehdi Mohammadi Iraj Faghiri Ehsan Abedi Ali Fakhri Ali Azimi Mohammad Ali Zahed 《Environmental monitoring and assessment》2014,186(11):7387-7398
Samples of surface sediments from the Iranian coast of the Persian Gulf were examined to determine the levels and sources of 15 polycyclic aromatic hydrocarbons (PAHs). Samples were collected from 30 sampling sites and analyzed for PAHs by gas chromatography–mass spectrometry (GC-MS). Total concentrations of PAHs ranged from 93 to 4,077 ng g?1 dry weight. The PAH composition from 30 sampling sites was dominated by four-ring PAH compounds. Molecular indices based on the ratios of PAH concentrations were used to differentiate PAHs from pyrolitic to petrogenic and mixed origins. The results suggested that the main sources of PAHs in sediments from the studied region were mixed pyrolitic and petrogenic. Furthermore, benthic organisms in most of the investigated areas were not at ecotoxicological risk, according to the results from the effects range low (ERL)/effects range median (ERM) techniques suggested by the US Sediment Quality Guidelines (SQGs). 相似文献
24.
A new simple and rapid ultrasound-assisted ionic liquid-based microextraction method was applied to preconcentrate aluminum(III),
gallium(III), and indium(III) ions from water samples as a prior step to their simultaneous spectrophotometric determination
using least squares support vector machines regression. In the novel procedure, 1-hexyl-3-methylimidazolium hexafluorophosphate
[C6MIM][PF6] was dispersed into the aqueous sample solution as fine droplets by ultrasonication, and the analytes were extracted into
the ionic liquid phase after complexation with 1,2,5,8-tetrahydroxy anthraquinone (quinalizarine). After centrifuging, the
fine droplets of extractant phase were settled to the bottom of the conical-bottom glass centrifuge tube. The detection limits
for Al(III), Ga(III), and In(III) were 1.70, 2.02, and 2.06 ng mL−1, respectively. The precision of the method, evaluated as the relative standard deviation obtained by analyzing a series of
ten replicates, was below 3.2% for all elements. The method was successfully applied for the determination of Al(III), Ga(III),
and In(III) in real samples. 相似文献
25.
Sheng Xin Peng Benhong Elahi Ehsan Wei Guo 《Environmental science and pollution research international》2019,26(25):25467-25475
Environmental Science and Pollution Research - This paper conducts a convergence analysis on the energy-environmental efficiency to explore the differences between regions that reflect the... 相似文献
26.
Banavi Parvaneh Sadeghi Ehsan Garavand Farhad Heydari Mahshid Rouhi Milad 《Environmental science and pollution research international》2020,27(31):38591-38601
Environmental Science and Pollution Research - The copper pots with an inner coating layer of tin have been remarkably used in many countries for a long time. In this study, leaching of some metals... 相似文献
27.
In this study a novel variant of friction stir processing was developed for producing of polymer metal surface or bulk composites in order to enhance the mechanical, electrical and thermal properties. For this purpose, a novel tooling system was designed consists of a rotating pin, a stationary shoulder and a heating system located inside the shoulder. In present paper, for preliminary study high-density polyethylene and copper powder was selected as polymeric matrix and metallic additive, respectively. Surface quality, microstructure, ultimate tensile strength and the modulus of elasticity were determined for each prepared sample. From experimental tests, it was found that this approach is an efficient method for producing of polymer–metal composites. 相似文献
28.
Introduction
Roadway safety is a major concern for the general public and public agencies, as roadway crashes claim many lives and cause substantial economic loss each year. In Iran, a large number of vehicles are involved in road accidents each year, which cause many deaths and extensive property damage; such accidents are among the major causes of death and disability in the country. Method: To reduce roadway accidents, the factors that affect the occurrence and severity of accidents should be scrutinized to prevent or reduce their effect. The method that many researchers have adopted to determine the effective parameters surrounding road accidents in recent years is through statistical modeling of accidents. In this article, the role of different kinds of vehicles in traffic flow are investigated separately in terms of the likelihood of crashes on urban highways, and the vehicles are divided into three groups: passenger cars, heavy vehicles, and light non-passenger car vehicles. Poisson and negative binomial (NB) regression models were applied to model the accidents in this research, which were categorized into two groups: no injury (property damage only) accidents and more severe (injury and fatal) accidents. Results: Ultimately, we conclude that light non-passenger car vehicles (i.e., taxis and motorcycles) play the largest role in the occurrence of crashes on urban highways for both types of accidents. 相似文献29.
Ehsan Aghdam Yingying Xiang Jianliang Sun Chii Shang Xin Yang Jingyun Fang 《环境科学学报(英文版)》2017,29(8):146-154
The formation of disinfection by-products(DBPs) from the degradation of N,N-diethyl-3-methyl benzoyl amide(DEET) and ibuprofen(IBP) by the ultraviolet irradiation(UV)/chlorine process and subsequent post-chlorination was investigated and compared with the UV/H_2O_2 process.The pseudo first-order rate constants of the degradation of DEET and IBP by the UV/chlorine process were 2 and 3.1 times higher than those by the UV/H_2O_2 process, respectively, under the tested conditions. This was due to the significant contributions of both reactive chlorine species U(RCS) and hydroxyl radicals(HO) in the UV/chlorine process. Trichloromethane, 1,1,1-trichloro-2-propanone and dichloroacetic acid were the major known DBPs formed after 90% of both DEET and IBP that were degraded by the UV/chlorine process. Their yields increased by over 50%after subsequent 1-day post-chlorination. The detected DBPs after the degradation of DEET and IBP comprised 13.5% and 19.8% of total organic chlorine(TOCl), respectively, and the proportions increased to 19.8% and 33.9% after subsequent chlorination, respectively. In comparison to the UV/H_2O_2 process accompanied with post-chlorination, the formation of DBPs and TOCl in the UV/chlorine process together with post-chlorination was 5%–63% higher,Ulikely due to the generation of more DBP precursors from the attack of RCS, in addition to HO. 相似文献
30.
Role of back diffusion and biodegradation reactions in sustaining an MTBE/TBA plume in alluvial media 总被引:1,自引:0,他引:1
Rasa E Chapman SW Bekins BA Fogg GE Scow KM Mackay DM 《Journal of contaminant hydrology》2011,126(3-4):235-247
A methyl tert-butyl ether (MTBE) / tert-butyl alcohol (TBA) plume originating from a gasoline spill in late 1994 at Vandenberg Air Force Base (VAFB) persisted for over 15 years within 200 feet of the original spill source. The plume persisted until 2010 despite excavation of the tanks and piping within months after the spill and excavations of additional contaminated sediments from the source area in 2007 and 2008. The probable history of MTBE concentrations along the plume centerline at its source was estimated using a wide variety of available information, including published details about the original spill, excavations and monitoring by VAFB consultants, and our own research data. Two-dimensional reactive transport simulations of MTBE along the plume centerline were conducted for a 20-year period following the spill. These analyses suggest that MTBE diffused from the thin anaerobic aquifer into the adjacent anaerobic silts and transformed to TBA in both aquifer and silt layers. The model reproduces the observation that after 2004 TBA was the dominant solute, diffusing back out of the silts into the aquifer and sustaining plume concentrations much longer than would have been the case in the absence of such diffusive exchange. Simulations also suggest that aerobic degradation of MTBE or TBA at the water table in the overlying silt layer significantly affected concentrations of MTBE and TBA by limiting the chemical mass available for back diffusion to the aquifer. 相似文献