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1.
Environmental Science and Pollution Research - The availability of natural energy resources and the environmental issues are the most significant issues that are often highlighted by the world...  相似文献   

2.

In this work, the development and usability of kapok oil in diesel engine was intended. With this purpose, the piston crowns are coated with mullite–lanthanum (ML) ceramic composite at varying compositions in order to reduce the heat rejection during combustion process. The kapok oil is blended with diesel fuel consisting of (20% kapok oil–80% diesel) volumetrically named B fuel. The B and diesel (D) fuels are taken for the engine performance test with different coated piston (ML1, ML2, and ML3) and exhaust gas recirculation (EGR—10%, 20%, and 30%), compression ratio (CR—16, 17, and 18) and engine load (50%, 75%, and 100%). Also, the engine performance study on brake thermal efficiency (BTE), brake-specific fuel consumption (BSFC), hydrocarbons (HCs), oxides of nitrogen (NOx), carbon monoxide (CO), smoke opacity, and numerical study using ANSYS software is carried out. When operated with ML2-coated pistons with B fuel, maximum BTE value of 29.2%, minimum BSFC value of 0.224 kg/kW-h, CO emission of 0.2%, and smoke opacity of 39 ppm were observed. The results showed that ML2-coated piston considerably improved the performance of the test engines when compared with ML1 and ML3 coatings. Except for NOx emission, all other pollutant emission values were reduced. The numerical analysis using ANSYS software for ML2-coated pistons showed better retention of in-cylinder chamber temperature.

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3.
Environmental Science and Pollution Research - Optimization of fuel injection strategies can maximize the utilization of ternary fuel by addressing the issues concerning fuel consumption, engine...  相似文献   

4.
Epidemiological data indicate that exposure to diesel exhaust particles (DEPs) from traffic emissions is associated with higher risk of morbidity and mortality related to cardiovascular and pulmonary diseases, accelerated progression of atherosclerotic plaques, and possible lung cancer. While the impact of DEPs from combustion of fossil diesel fuel on human health has been extensively studied, current knowledge of DEPs from combustion of biofuels provides limited and inconsistent information about its mutagenicity and genotoxicity, as well as possible adverse health risks. The objective of the present work was to compare the genotoxicity of DEPs from combustion of two first-generation fuels, 7% fatty acid methyl esters (FAME) (B7) and 20% FAME (B20), and a second-generation 20% FAME/hydrotreated vegetable oil (SHB: synthetic hydrocarbon biofuel) fuel. Our results revealed that particulate engine emissions from each type of biodiesel fuel induced genotoxic effects in BEAS-2B and A549 cells, manifested as the increased levels of single-strand breaks, the increased frequencies of micronuclei, or the deregulated expression of genes involved in DNA damage signaling pathways. We also found that none of the tested DEPs showed the induction of oxidative DNA damage and the gamma-H2AX-detectable double-strand breaks. The most pronounced differences concerning the tested particles were observed for the induction of single-strand breaks, with the greatest genotoxicity being associated with the B7-derived DEPs. The differences in other effects between DEPs from the different biodiesel blend percentage and biodiesel feedstock were also observed, but the magnitude of these variations was limited.  相似文献   

5.

The automobile exhausts are one of the major sources of particulate matter in urban areas and these particles are known to influence the atmospheric chemistry in a variety of ways. Because of this, the oxidation of dissolved sulfur dioxide by oxygen was studied in aqueous suspensions of particulates, obtained by scraping the particles deposited inside a diesel truck exhaust pipe (DEP). A variation in pH showed the rate to increase with increase in pH from 5.22 to about ~6.3 and to decrease thereafter becoming very slow at pH?=?8.2. In acetate-buffered medium, the reaction rate was higher than the rate in unbuffered medium at the same pH. Further, the rate was found to be higher in suspension than in the leachate under otherwise identical conditions. And, the reaction rate in the blank reaction was the slowest. This appears to be due to catalysis by leached metal ions in leachate and due to catalysis by leached metal ions and particulate surface both in suspensions. The kinetics of dissolved SO2 oxidation in acetate-buffered medium as well as in unbuffered medium at pH?=?5.22 were defined by rate law: k obs ?=?k 0?+?k cat [DEP], where k obs and k 0 are observed rate constants in the presence and the absence of DEP and k cat is the rate constant for DEP-catalyzed pathway. At pH?=?8.2, the reaction rate was strongly inhibited by DEP in buffered and unbuffered media. Results suggest that the DEP would have an inhibiting effect in those areas where rainwater pH is 7 or more. These results at high pH are of particular significance to the Indian subcontinent, because of high rainwater pH. Conversely, it indicates the DEP to retard the oxidation of dissolved SO2 and control rainwater acidification.

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6.
There is a growing market demand for small-scale biomass gasifiers that is driven by the economic incentives and the legislative framework. Small-scale gasifiers produce a gaseous fuel, commonly referred to as producer gas, with relatively low heating value. Thus, the most common energy conversion systems that are coupled with small-scale gasifiers are internal combustion engines. In order to increase the electrical efficiency, the operators choose dual fuel engines and mix the producer gas with diesel. The Wiebe function has been a valuable tool for assessing the efficiency of dual fuel internal combustion engines. This study introduces a thermodynamic model that works in parallel with the Wiebe function and calculates the emissions of the engines. This “vis-à-vis” approach takes into consideration the actual conditions inside the cylinders—as they are returned by the Wiebe function—and calculates the final thermodynamic equilibrium of the flue gases mixture. This approach aims to enhance the operation of the dual fuel internal combustion engines by identifying the optimal operating conditions and—at the same time—advance pollution control and minimize the environmental impact.  相似文献   

7.

Radiation use efficiency (RUE) is considered critical for calculation of crop yield. The crop productivity can be improved by increasing the interception of solar radiation and maintaining higher RUE for plants. Irrigation water and nitrogen (N) supply are the main limiting factors for RUE in maize (Zea mays L.) across the semi-arid environments. Field experiments were conducted during two consecutive growing seasons (2009–2010) to optimize RUE in relation to N application timings and rates with varying irrigation water management practices. In experiment 1, three N application timings were made, while in experiment 2, three possible water management practices were used. In both experiments, five N rates (100, 150, 200, 250, and 300 kg N ha−1) were applied to evaluate the effects of irrigation water and N on cumulative photosynthetic active radiation (PARi), dry matter RUE (RUEDM), and grain yield RUE (RUEGY). The results demonstrated that cumulative PARi and RUEs were not constant during the plant growth under varying the nutrients. The water and N significantly influenced cumulative PARi and RUEs during the both growing seasons. In experiment 1, the maximum cumulative PARi was observed by application of 250 kg N ha−1 in three splits (1/3 N at V2, 1/3 N at V16, and 1/3 N at R1 stage), and the highest RUEDM was achieved by the application of 300 kg N ha−1. However, the highest RUEGY was observed by application of 250 kg N ha−1. In experiment 2, the maximum cumulative PARi was attained at normal irrigation regime with 250 kg N ha−1, while the highest RUEDM and RUEGY were recorded at normal irrigation regime with the application of 300 kg N ha−1. The regression analysis showed significant and positive correlation of RUEGY with grain yield. Therefore, optimum water and N doses are important for attaining higher RUE, which may enhance maize grain yield semi-arid environment; this may be considered in formulating good agricultural practices for the environmental conditions resembling to those of this study.

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8.
Environmental Science and Pollution Research - The aim of this study is to investigate the effect of the polymethyl acrylate (PMA) additive on the formation of particulate matter (PM) and nitrogen...  相似文献   

9.
Environmental Science and Pollution Research - Since the power unbundling reform in 2002, China’s power industry has been a typical sector moving towards marketization. The supply-side...  相似文献   

10.
Environmental Science and Pollution Research - This article uses the super-efficiency DEA method to measure the efficiency of the sports industry ecosystem and uses Tobit model to study its...  相似文献   

11.
This study analyzes the influence of fine particles PM2.5 on nonprogrammed children’s hospital admissions that occurred in the city of Seville between 2007 and 2011, and makes an economic assessment of the cost of the children’s hospital admissions for respiratory causes due to particle pollution. The PM2.5 dose-response functions for each type of hospital admission were used to quantify the cost of the hospital admissions. It can be concluded that the PM2.5 concentrations have negative effects on bronchiolitis, pneumonia, asthma, and bronchitis and other causes. A reduction of the daily average annual PM2.5 concentration from the existing levels to 10 µg/m3 would show an annual average reduction of children’s hospital admissions due to respiratory diseases of 0.09 cases. This paper shows that the daily average cost for children hospital admissions due to respiratory reasons in the city of Seville, associated with daily average annual levels of PM2.5 above 10 µg/m3, was almost 200€.

Implications:?Elevated PM2.5 concentrations in Seville have negative effects on children’s bronchiolitis, pneumonia, asthma, and bronchitis and other causes. A reduction of the daily average annual PM2.5 concentration from the existing levels to 10 μg/m3 would suppose an annual mean reduction of children’s hospital admissions due to respiratory diseases of 0.09 cases.  相似文献   

12.
Environmental Science and Pollution Research - China’s economy in the past 10 years has developed rapidly and achieved great success, but at the same time, environmental problems...  相似文献   

13.
Environmental Science and Pollution Research - Global prevalence trend and regional differences of coal worker’s pneumoconiosis (CWP) remain unclear. This study aimed to provide systematic...  相似文献   

14.
Environmental Science and Pollution Research - Environmental quality and economic growth are important factors that need to be balanced for sustainable development, especially in developing...  相似文献   

15.
Environmental Science and Pollution Research - Compared with developed nations, developing countries are more vulnerable to climate change and variability. In this study, a coping and adaptation...  相似文献   

16.
Environmental Science and Pollution Research - This study attempts to construct an econometric model using China’s natural disaster losses and macro-industry development data from 1980 to...  相似文献   

17.
Abstract

Butanol, ether, toluene, and hexane, which have Henry's constants ranging from 0.0005 to 53, were used to investigate the effects of substrate solubility or availability on the removal of volatile organic compounds (VOCs) in trickle-bed biofilters. Results from this study suggest that, although removal of a VOC generally increases with a decrease in its Henry's constant, an optimal Henry's constant range for biofiltration may exist. For the treatment of VOCs with high Henry's constant values, such as hexane and toluene, the transfer of VOCs between the vapor and liquid phases or between the vapor phase and the biofilm is a rate-determining step. However, oxygen (O2) transfer may become a rate-limiting step in treating VOCs with low Henry's constants, such as butanol, especially at high organic loadings. The results demonstrated that in a gas-phase aerobic biofilter, nitrate can serve both as a growth-controlling nutrient and as an electron acceptor in a biofilm for the respiration of VOCs with low Henry's constants. Microbial communities within the biofilters were examined using denaturing gradient gel electrophoresis to provide a more complete picture of the effect of O2 limitation and denitrification on biofilter performance.  相似文献   

18.
Environmental Science and Pollution Research - The report of the 19th National Congress of the Communist Party of China (CPC) stated: “We should focus on the construction of One Belt and one...  相似文献   

19.
Environmental Science and Pollution Research - The database of the Global Trade Analysis Project (GTAP) and its energy–environmental model, known as GTAP-E, are used in this study to simulate...  相似文献   

20.

With the rapid development of China’s economy, high energy consumption and high pollution emission have become serious problems. To solve these problems, many studies have been done to evaluate energy and environmental efficiency, as the results can provide valuable information to improve performance. However, the previous research mainly evaluates China’s regional energy and environmental efficiency by considering each region’s industry as a whole system, ignoring the internal structure. In reality, each region mainly includes three parallel types of industry: primary, secondary, and tertiary. Therefore, this paper provides a parallel data envelopment analysis (DEA) approach to evaluate China’s regional energy and environment efficiency by considering these parallel industrial systems. The following findings can be obtained based on the empirical results: (1) the overall energy efficiency of China is low, and the inefficiency of the economic system is mainly sourced from the lower energy and environmental performance of the primary industry and the tertiary industry. (2) the introduction of the environmental variable (CO2) leads to the increase of some backward areas’ efficiencies. (3) the energy efficiency of each provincial region is different, and most of them have their own inefficient industries. (4) the total factor productivity of China is declining, mainly because of the decline of technical efficiency.

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