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991.
Ahmed I. El-Seesy Mohamed Nour Ali M. A. Attia Hamdy Hassan 《International Journal of Green Energy》2020,17(3):233-253
ABSTRACTThis article aims to study the influence of the addition of graphene oxide nanoparticles (GO) to diesel/higher alcohols blends on the combustion, emission, and exergy parameters of a CI engine under various engine loads. The higher alcohols mainly n-butanol, n-heptanol, and n-octanol are blended with diesel at a volume fraction of 50%. Then, the 25 and 50 mg/L concentrations of GO are dispersed into diesel/higher alcohols blends using an ultrasonicator. The GO structures are examined using TEM, TGA, XRD and FTIR. The findings show that there is a reduction in pmax. and HRR when adding higher alcohols with diesel fuel. Regarding engine emission, there is a significant improvement in emissions formation with adding higher alcohols. The addition of GO into diesel/higher alcohols blends improves the brake thermal efficiency by 15%. Moreover, the pmax. and HRR are both enhanced by 4%. The CO, UHC and smoke formation are reduced considerably by 40%, 50 and 20%, respectively, while NOx level is increased by 30% with adding GO. Finally, adding high percentages of n-butanol, n-heptanol, and n-octanol with diesel fuel with the presence of GO has the potential to achieve ultra-low CO, UHC, and smoke formation meanwhile keeping high thermal efficiency level. 相似文献
992.
Investigation of sustainable energy alternatives for powering remote communities in northern Ontario
ABSTRACT Remote communities in the North of Ontario survive in isolation as their proximity to the southern industrial sector of the province limits their accessibility to the major grid. The lack of grid connection has led to antiquated methods of power generation which pollute the environment and deplete the planet of its natural resources. Aside from the primary means of electricity generation being by diesel generators, generation infrastructure is deteriorating due to age and the stagnation of the power supply has led to communities facing load restrictions. These challenges may be resolved by introducing clean energy alternatives and providing a fuel blend option. The primary energy sources investigated in this research are solar, wind, and hydrogen. To assess the viability of these energy production methods in Northern communities, an exergy analysis is employed as it utilizes both the first and second law of thermodynamics to determine systems’ efficiency and performance in the surroundings. Local weather patterns were used to determine the viability of using wind turbines, solar panels and/or hydrogen fuel cells in a remote community. Through analysis of the resources available at the community, it was determined that the hydrogen fuel cell was best suited to provide clean energy to the community. Wind resulted in low efficiency in the range of 2–3% while solar efficiencies resulted in ranges of 18 – 19%, as the seasonal variations between the three years is not very great. Due to the higher operating efficiencies observed of the PV panels it would also be an attractive alternative to diesel generators however, the lack of consistent operation above 30% efficiency throughout the year, resulted in hydrogen fuel cells being a better alternative. 相似文献
993.
Campos Felipe S. Loureno-de-Moraes Ricardo Ruas Danilo S. Mira-Mendes Caio V. Franch Marc Llorente Gustavo A. Sol Mirco Cabral Pedro 《Environmental management》2020,65(1):46-61
Environmental Management - Ecological connectivity depends on key elements within the landscape, which can support ecological fluxes, species richness and long-term viability of a biological... 相似文献
994.
Hewitt Richard J. Pera Florencia A. Garca-Martn Mara Gaudry-Sada Karl-Heinz Hernndez-Jimnez Vernica Bieling Claudia 《Environmental management》2020,65(3):334-354
Environmental Management - Landscapes are changing, with rural areas becoming increasingly urbanized. Children and adolescents are underrepresented in the sense-of-place literature. Our study aimed... 相似文献
995.
Environmental Management - Monitoring long-term changes in aquatic biodiversity requires the effective use of historical data that were collected with different methods and varying levels of... 相似文献
996.
Whatman No. 1 filters impregnated with a 3% solution of oxalic acid in ethanol which are used for elimination of ammonia from the air stream before entering the absorber for collecting SO2, were tested for a possible application (a) in the spectrophotometric determination of ammonia with Nessler's reagent and (b) in the reflectometric determination of smoke. It was shown that impregnated filters were as suitable for the determination of ammonia as absorbing solution and as applicable for smoke measurement as untreated filters. Further, the advantage of using impregnated filters for sampling ammonia lies in avoiding the interference of organic vapours which may occur, if absorbing solution is used. 相似文献
997.
R. Harkov A. Greenberg F. Darack L. Mcgeorge C. Pietarinen 《Environmental monitoring and assessment》1987,9(1):83-92
Quality assurance (QA) assessments of air pollution data sets provide a basis for evaluating the significance of various substances in the atmosphere. For non-criteria pollutants, QA results are seldom reported in the technical literature and are often difficult to estimate. The present report provides a summary of QA results such as recovery, precision and accuracy data. Of the six trace elements and nine organic constituents compared in detail, recoveries, laboratory precision and laboratory accuracy values were 100%, ±3% to ±19% and-2 to-13% for the former group and 69% to 98%, ±7% to 23% and-15 to-34% for the later group. System precision varied from ±22% to ±47% for the trace elements and ±42% to ±83% for the organic constituents. Limitations in the interpretation of non-criteria particulate-phase pollutant data bases are discussed with some emphasis placed on receptor-modelling and risk assessment applications. Finally, the relevance of NBS certified materials for QA estimates in non-criteria air pollutant studies is also reviewed. 相似文献
998.
999.
Erin A. Hopkins 《国际发展与全球生态学杂志》2018,25(3):206-215
Transit-oriented development (TOD) is becoming an increasingly common development strategy with potential consequences on property values. This study explores the potential relationship between the proximity to public transportation and housing values. The objective is achieved by performing a hedonic regression using the 2013 American Housing Survey (AHS) sample, which includes 25 metro areas. In 2013, the AHS added a topical supplement addressing public transportation issues which makes understanding public transportation impacts on housing values more feasible. In this study, being located within half a mile of a public transportation stop was a significant factor in explaining housing values for 6 out of 25 metro areas. This research is important to real estate practitioners operating within TODs as proximity to public transportation may significantly influence property values. 相似文献
1000.
Planning in sustainable development is believed to be an important element in allowing higher education institutions to set their goals and to commit themselves towards undertaking concrete actions and measures at all levels in order to implement sustainability. Yet, there is a paucity of research that has looked at the extent to which planning can support institutions of higher education to assess their performances and to determine whether the set aims have been met. This research gap needs to be met to allow a better understanding of how planning can help to promote the integration of the three components of sustainable development – economic development, social development and environmental protection in higher education. This paper explores the challenges for planning the sustainable development in higher education, also outlining the potentials lessons learned that could assist in improving Education for Sustainable Development efforts in Higher Education Institutions. Among its main results are the fact that many universities wish to pursue sustainable development, but their efforts are hindered by lack of institutional support and planning and limited emphasis on approaches, such as problem-based learning. The universities that are engaged in the field have to face many problems, varying from limited resources to lack of trained staff. As a result, integrated approaches to sustainability become difficult to implement. Finally, the paper has identified the fact that many opportunities offered mainstream developments, such as the UN Declaration ‘The World we Want’ or the UN Sustainable Development Goals are not being put to full use. 相似文献