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421.
Jordan faces stringent energy challenges mainly in the form of import dependence and escalating demand. The building sector accounts for 58% of total national electricity consumption and therefore plays an important role in addressing these challenges. This article investigates how energy efficiency in green buildings certified by the Leadership in Energy and Environmental Design (LEED) rating system contribute towards achieving United Nations (UN) Sustainable Development Goals (SDGs) in Jordan. Furthermore, this paper proposes a new Comprehensive Contribution to Sustainable Development Index (CCSDI) to assess the contributions of implementation of the LEED 2009 prerequisites and credits in the Energy and Atmosphere (EA) category to achieve UN SDGs in Jordan. Questionnaire surveys were conducted to obtain data. Relative Importance Index (RII) method was used to evaluate the contributions of LEED 2009 prerequisites and credits in the EA category. Results indicate a positive relationship between the LEED 2009 prerequisites and credits in category and UN SDGs 7?9 and 12?13. We conclude that our proposed CCSDI is a robust tool for assessing the contribution of energy efficiency in LEED 2009 certified green buildings towards achieving UN SDGs in Jordan.  相似文献   
422.
This research is aimed at addressing the complaints of local people living near chicken farms who are disturbed by odors caused by livestock activities, and specifically, by the generation of ammonia gas from chicken manure. Methods that are expected to reduce the intensity of ammonia gas odors include both scattering lime on the surface of the soil and planting soybeans around the cages. The results obtained showed a reduction in the levels of ammonia gas by 57.48%–from 1.67 parts per million (ppm) near an untreated cage to 0.71 ppm near the cage that achieved the best results. The study found that spreading lime evenly over the chicken manure was the most effective method that farmers could use to reduce ammonia odors. The sample area treated by the addition of soybean plants showed a reduction in the levels of ammonia gas from 1.67 to 0.78 ppm.  相似文献   
423.
The effects of porous media grain size distribution on the transport and deposition of polydisperse suspended particles under different flow velocities were investigated. Selected Kaolinite particles(2–30 μm) and Fluorescein(dissolved tracer) were injected in the porous media by step input injection technique. Three sands filled columns were used: Fine sand,Coarse sand, and a third sand(Mixture) obtained by mixing the two last sands in equal weight proportion. The porous media performance on the particle removal was evaluated by analysing particles breakthrough curves, hydro-dispersive parameters determined using the analytical solution of convection–dispersion equation with a first order deposition kinetics, particles deposition profiles, and particle-size distribution of the recovered and the deposited particles. The deposition kinetics and the longitudinal hydrodynamic dispersion coefficients are controlled by the porous media grain size distribution. Mixture sand is more dispersive than Fine and Coarse sands. More the uniformity coefficient of the porous medium is large, higher is the filtration efficiency. At low velocities, porous media capture all sizes of suspended particles injected with larger ones mainly captured at the entrance.A high flow velocity carries the particles deeper into the porous media, producing more gradual changes in the deposition profile. The median diameter of the deposited particles at different depth increases with flow velocity. The large grain size distribution leads to build narrow pores enhancing the deposition of the particles by straining.  相似文献   
424.
Hepatitis E is an important public health concern throughout the world. Many molecular and serological surveys have reported the prevalence and genotypic characteristics of HEV in humans and animals worldwide. However, the genotypic characterization of this virus is very limited in Tibetan pigs. Hence, we aimed to explore the genotype of HEV, prevailing among Tibetan pigs in China. For this purpose, 253 bile samples of Tibetan pigs (free-range animals) were collected from different slaughterhouses during 2017–2018 and subsequently tested for HEV RNA by RT-nPCR. A total of 11 out of 253 (4.35%) samples tested were positive for HEV RNA. Based on the sequence alignment and phylogenetic analysis, all the isolated HEV strains belonged to genotype 4 and clustered into subtype 4b by sharing more than 84.8–95.2% identities with other reported strains. Our results concluded that HEV genotype 4 is prevailing among Tibetan pigs in Tibet, China.  相似文献   
425.
The purpose of this paper is to develop a methodology to evaluate the feasibility of using landfill gas (LFG) as a liquefied natural gas (LNG) fuel source for heavy-duty refuse trucks operating on landfills. Using LFG as a vehicle fuel can make the landfills more self-sustaining, reduce their dependence on fossil fuels, and reduce emissions and greenhouse gases. Acrion Technologies Inc. in association with Mack Trucks Inc. developed a technology to generate LNG from LFG using the CO2 WASH process. A successful application of this process was performed at the Eco Complex in Burlington County, PA. During this application two LNG refuse trucks were operated for 600 hr each using LNG produced from gases from the landfill. The methodology developed in this paper can evaluate the feasibility of three LFG options: doing nothing, electricity generation, and producing LNG to fuel refuse trucks. The methodology involved the modeling of several components: LFG generation, energy recovery processes, fleet operations, economic feasibility, and decision-making. The economic feasibility considers factors such as capital, maintenance, operational, and fuel costs, emissions and tax benefits, and the sale of products such as surplus LNG and food-grade carbon dioxide (CO2). Texas was used as a case study. The 96 landfills in Texas were prioritized and 17 landfills were identified that showed potential for converting LFG to LNG for use as a refuse truck fuel. The methodology was applied to a pilot landfill in El Paso, TX. The analysis showed that converting LFG to LNG to fuel refuse trucks proved to be the most feasible option and that the methodology can be applied for any landfill that considers this option.  相似文献   
426.
Genotypic variation of nitrogen use efficiency in Indian mustard   总被引:1,自引:0,他引:1  
This experiment was conducted to investigate the variation of nitrogen efficiency (NE), nitrogen uptake efficiency (UE), physiological nitrogen use efficiency (PUE) among Indian mustard genotypes, grown under N-insufficient and N-sufficient conditions. Nitrogen efficiency varied from 52.7 to 92.8. Seed yield varied from 1.14 t ha(-1) to 3.21 t ha(-1) under N-insufficient condition, while 2.14 t ha(-1)-3.33 t ha(-1) under N-sufficient condition. Physiological basis of this difference was explained in terms of nitrogen uptake efficiency and physiological nitrogen use efficiency, and their relationship with the growth and yield characteristics. While nitrogen uptake efficiency was positively correlated with plant biomass (0.793**), leaf area index (0.664*), and leaf nitrogen content (0.783**), physiological nitrogen use efficiency is positively correlated with photosynthetic rate (0.689**) and yield (0.814**). This study suggests that genotype having high nitrogen uptake efficiency and high physiological nitrogen use efficiency might help in reducing the nitrogen load on soil without any penalty on the yield.  相似文献   
427.
GOAL, SCOPE AND BACKGROUND: One of the principal experimental variables which effect the results of phosphorus (P) sorption studies is the ionic composition, in addition to both species and concentrations of the contacting solution. In spite of the realization that ionic species, concentrations and their compositions effect P sorption and/or desorption, most of the salt-related studies are confined to Cl- (anion) in association with different cations. While the knowledge about the comparative response of P to Cl- and SO4(2-) ions was lacking, the current study was conducted to evaluate the comparative effects of anions (in association with cations) on inorganic P release and P fractions in the soil. METHODS: The test soil was amended with livestock compost manure (OP); KH2PO4 (IPk) or Ca(H2PO4)2 (IPc) at a rate of 1ppm. Soil was subjected to one salt and nine subsequent water extractions and different P fractions were measured. Four salt types, NaCl, Na2SO4, KCl and K2SO4, were used at levels of 0.5 M. RESULTS: Irrespective of P sources, P release was substantially increased in the salt-pretreated soil as compared to the non-saline soil. Sulfate salts released more P in subsequent water extractions than Cl-. Phosphorus release decreased for salt types with Na2SO4 > NaCl > K2SO4 > KCl and for P sources with OP approximately IPk > Control (without P application) > IPc, respectively. DISCUSSION: No previous study was found to compare the results of more P release by SO4(2-) than Cl- salt. Most of the previous studies focused on anion sorption capacities, but the mechanism for their adsorption is not fully known. Most of the authors suggested that the mechanisms of SO4(2-) and PO4(3-) adsorption are similar, and that both ions compete for the same sorption sites (Kamprath et al. 1956, Couto et al. 1979, Pasricha and Fox 1993). Although adsorbed SO4(2-) does not compete strongly with PO4(3-), there is likely to be some competition for sorption between these anions which may cause comparatively more P release by SO4(2-) than Cl- salts. Higher P release by Na-saturation could be due to the release of P associated with oxide surfaces or due to dissolution of Ca-P phases (Curtin et al. 1987). CONCLUSIONS: Study clearly showed that not only cations species differ for P desorption capacity, but associated anions also play a vital role in the fate of P under saline environments. Synergetic effects exist between Na and SO4(2-) ions which enhanced the P release. This study has also confirmed the fact that P from organic sources is available as well as from inorganic P sources. However, P release depends more on the type of P source applied than on total P. RECOMMENDATIONS AND PERSPECTIVES: It is highly recommended that more than one anion species must be used in the research plans for evaluating the P response in a saline environment. The results have important implications from the point of view of research, as most of the researchers focus on different cations only for evaluating P response to salts from an environmental point of view. However, our study has made it clear that anions in association with cations differed for their effects on P release.  相似文献   
428.
The soil quality of urban parks is of vital importance as the children playing in the parks get themselves easily contaminated. A study was conducted to assess the level of elemental pollution caused by constant urbanization and industrialization, in various parks of Islamabad and Rawalpindi. The soil samples, collected from 14 urban parks of Islamabad and Rawalpindi areas, were analysed for their elemental concentrations. In each sample, 32 elements were quantified using semi-absolute k (0)-instrumental neutron activation analysis and flame atomic absorption spectrophotometry. The quality of analysis was assured by analysing the International Atomic Energy Agency (IAEA) reference material IAEA-S7 (soil). The pollution level was assessed by enrichment factor, pollution load index and our suggested indicator called "average toxic element concentration". The elemental concentrations measured in the parks of two cities were compared by t test. Four sources of different elements in the soils were identified by employing principal component analysis and cluster analysis. The results of multivariate techniques grouped all parks into four classes. The use of enrichment factor indicated the presence of Ni at slightly higher level in all parks while the pollution load index revealed that the parks of Rawalpindi were relatively more polluted as compared to that of Islamabad. The hot spot areas of elemental concentration were closely related to high traffic conditions.  相似文献   
429.
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