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81.
Biodiesel of waste cooking oil origin is gaining attention as a replacement for current fossil fuels, as its low-priced, recycled feedstock shall prevent food source competition, which is estimated to happen with current biodiesel production processes. As a result, waste cooking oil has been claimed to be a highly potential feedstock for biodiesel production. In the present research work, Fe-Mn doped sulphated zirconia catalyst was synthesized and used in simultaneous esterification and transesterification of waste cooking oil to biodiesel synthesis. The catalyst was prepared through the impregnation method and characterized by using XRD, TPD-NH3, FT-IR, BET, and TEM. Response surface methodology (RSM) in conjunction with the central composite design (CCD) was applied to statistically evaluate and optimize the biodiesel preparation process. It was found that the synthesis of biodiesel achieved an optimum level of 97.2% waste cooking oil methyl ester’s (WCOME’s) yield at the following reaction conditions: methanol/oil molar ratio: 10:1, catalyst concentration: 3.0 wt %, and reaction temperature: 160 °C. The extremely high WCOME’s yield of 97.2% was proved to be due to high acidity, surface area, and large pore diameter; reactants can easily diffuse into the interior pore of the catalyst and allow them to be in contact with active sites that enhance catalytic activity. 相似文献
82.
Aansa Rukya Saleem Fakhra Rashid Audil Rashid Tariq Mahmood Waqar-un-Nisa 《中国人口.资源与环境(英文版)》2014,(4):345-353
Margalla Hills National Park(MHNP) is a declared natural reserve of Pakistan,and Saidpur village is located at its foothills.To sustain livelihood,Saidpur community relies on natural resources and has established an intriguing relationship with the surrounding ecosystem.Human intrusion and related impacts were investigated through self-structured questionnaire from village community to gather information about demography,life practices,natural resource use,and their perception about the environment.Quadrat analysis revealed that the overall plant density was<4 plants/m~2,whereas ordination biplot has indicated significant reduction in plant cover and sparse distribution of species in areas close to human settlement.Survey results show that more than 50%families rely on forest wood as fuel source.Logistic regression has identified education paucity(odds ratio,OR=2.6,95%confidence interval,CI=1.0-6.7),large family size(OR= 5.0,95%CI=1.5-16.6),and fuel type(OR=3.5,95%CI=1.2-9.9)as significant predictors of accelerated forest cutting in MHNP.Male members were mostly illiterate and in favor to promote construction activities which reflects their low concern and casual attitude toward resource conservation.In this study,lack of awareness and peoples’ dependency on natural resources emerged as priority challenges,and hence,we suggest provision of alternate fuel sources,better education and sustained income resources as incentives to bring behavioral change.It is pivotal to involve local community before the adoption of any conservation plan as intervention strategy to protect MHNP ecosystem. 相似文献
83.
Understanding of groundwater salinity using statistical modeling in a small tropical island,East Malaysia 总被引:1,自引:0,他引:1
Sarva Mangala Praveena Mohd Harun Abdullah Kawi Bidin Ahmad Zaharin Aris 《The Environmentalist》2011,31(3):279-287
This paper presents an understanding of groundwater salinity by identification of effective factors using chemometric methods
(cluster analysis and multiple linear regressions) in Manukan Island, Sabah. Local groundwater and environmental properties
were used to explore the effective factors of groundwater salinity. Cluster analysis showed salinity and chloride illustrated
the highest similarities. Electrical conductivity and total dissolved solids were also grouped in the same cluster. Seawater
is the only chloride source in groundwater of Manukan Island demonstrated an indication of seawater mixing in freshwater.
It is an effect of upward movement of the seawater by pumping activities. Precipitation and evapotranspiration (environmental
condition) with hydraulic heads were clustered together to show that they also influence salinity concentration in groundwater.
Multiple linear regressions showed descending order of the factors from chloride (the largest contribution) to evapotranspiration
(the smallest contribution) and illustrated the contribution to groundwater salinity in Manukan Island. The integrated results
using chemometric methods have provided a way to identify the effective factors on groundwater salinity. This similar approach
and resulting equation can be applied in other small tropical islands with alike hydrogeological condition and limited information
available for a better understanding of its groundwater salinity. 相似文献
84.
Khan Haroon ur Rashid Usman Bushra Zaman Khalid Nassani Abdelmohsen A. Haffar Mohamed Muneer Gulnaz 《Environmental science and pollution research international》2022,29(24):35884-35896
Environmental Science and Pollution Research - Climate finance and carbon pricing are regarded as sustainable policy mechanisms for mitigating negative environmental externalities via the... 相似文献
85.
Yousafzai Saba Saeed Rashid Rahman Ghani Farish Sidra 《Environmental science and pollution research international》2022,29(54):81337-81350
Environmental Science and Pollution Research - Urbanization is the main force of the global environmental as well as land use land cover changes (LULC). Urbanization is caused by prompt increase in... 相似文献
86.
Rashid Reza Owlia Ahmad Abrishamchi Massoud Tajrishy 《Environmental monitoring and assessment》2011,172(1-4):263-273
Assessment of groundwater quality monitoring networks requires methods to determine the potential efficiency and cost-effectiveness of the current monitoring programs. To this end, the concept of entropy has been considered as a promising method in previous studies since it quantitatively measures the information produced by a network. In this study, the measure of transinformation in the discrete entropy theory and the transinformation?Cdistance (T?CD) curves, which are used frequently by other researchers, are used to quantify the efficiency of a monitoring network. This paper introduces a new approach to decrease dispersion in results by performing cluster analysis that uses fuzzy equivalence relations. As a result, the sampling (temporal) frequency determination method also recommends the future sampling frequencies for each location based on certain criteria such as direction, magnitude, correlation with neighboring stations, and uncertainty of the concentration trend derived from representative historical concentration data. The proposed methodology is applied to groundwater resources in the Tehran?CKaradj aquifer, Tehran, Iran. 相似文献
87.
Tianhua Huang Alan Dennis Wendy S. Meschino Shamim Rashid Ellen Mak-Tam Howard Cuckle 《黑龙江环境通报》2015,35(7):709-716
88.
89.
K A Rashid J G Babish R O Mumma 《Journal of environmental science and health. Part. B》1984,19(8-9):689-701
Hepatic S9 preparations from Aroclor 1254 induced rats and 3-methylcholanthrene induced woodchucks were used to investigate, in vitro, the mutagenic potential of five amino acid conjugates of 2,4-Dichlorophenoxyacetic acid (alanine, aspartic acid, leucine, methionine and tryptophan). Five strains of Salmonella typhimurium (TA97, TA98, TA100, TA1535, TA1538) were utilized for this purpose. Dose-response effects producing a two-fold increase of revertants over spontaneous levels were not observed with either S9 preparation indicating that the amino acid conjugates are not promutagens in these assays. 相似文献
90.