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791.
Environmental Science and Pollution Research - The present work aims to investigate seasonal variations in air pollution levels in Lucknow and assess the ambient air quality of the city together...  相似文献   
792.
Environmental Science and Pollution Research - Urbanization is a rapidly growing phenomenon that affects wildlife. Laboratory studies show the effects of night light on the physiology of the...  相似文献   
793.
Environmental Science and Pollution Research - This paper intends to show the aspects of an environment-friendly hybrid energy system (HES) for reducing the electrical power problems in remote...  相似文献   
794.
Environmental Science and Pollution Research - The study represents the seasonal characteristics (carbonaceous aerosols and elements) and the contribution of prominent sources of PM2.5 and PM10 in...  相似文献   
795.
Environmental Science and Pollution Research - Evaluation of water quality is a priority work nowadays. In order to monitor and map, the water quality for a wide range on different scales (spatial,...  相似文献   
796.

The performance of engine parameters is more influenced with fuel injection strategies namely start of main injection timing (SoMI). An experimental analysis was performed to find the optimum SoMI timing based on performance, emission, and combustion characteristics. Base fuel of diesel and neem biodiesel was used as test fuels. The neem biodiesel was prepared by esterification and transesterification process. It is found from literature that neem biodiesel blend NB20 with diesel gives optimum performance and emission characteristics; therefore, NB20 blend was used for experiments. A variable geometry turbocharger (VGT) compression ignition (CI) engine was used to conduct the experiments. Engine performance parameters were estimated and compared with a base fuel of diesel and with NB20 blends. In this experimentation, fuel injection pressure (FIP) of 800 bar and engine speed of 1700 rpm were considered. SoMI timing was varied from 2° to 10° bTDC with an increment of 2° bTDC timing. Cylinder pressure (CP) and heat release rate (HRR) were estimated and found that are higher for diesel fuel compared to NB20 blend at different SoMI timings. The addition of neem biodiesel NB20 blend to diesel fuel decreases the exhaust emissions except NOx emissions. The BSFC was considerably reduced and BTE was improved almost equivalent to the diesel fuel for NB20. From the results, it is concluded that 10° bTDC SoMI timing provides 13% improvement in BTE, 21% decrement in BSFC, and 7.5% reduction in CO2 emissions.

  相似文献   
797.
Environmental Science and Pollution Research - Compression ignition engines powered by diesel are the work horses of developing countries like India. However, burning fossil fuel causes a lot of...  相似文献   
798.
Environmental Science and Pollution Research - The exhaust emissions from the compression ignition engines are harmful to both human beings and the environment. After-treatment devices placed in...  相似文献   
799.
The elliptical vibration cutting (EVC) technique has been found to be a promising technique for ultraprecision machining of various materials. In each overlapping EVC cycle, the thickness of cut (TOC) of work material, and the tool velocity get continuously varied. These two inherent phenomena, in fact, introduce transient characteristics into its cutting mechanics, which are considered to be different from the one applied for conventional cutting technique. Recently, a few theoretical models have been developed to understand the material removal mechanism with the EVC technique; however, in those studies, the transient phenomena were not considered. In the present research, an analytical force model for the orthogonal EVC process was developed in order to fully understand the EVC mechanism, and to more accurately predict the transient cutting force values. Three important factors: (i) transient TOC, (ii) transient shear angle, and (iii) transition characteristic of friction reversal were investigated and analyzed mainly based on geometric modeling and the Lee and Shaffer's slip-line solution. Mathematical evaluation shows that they may have significant influence on EVC process, and thus on its output performance. In order to validate the proposed force model, a series of low-frequency orthogonal EVC tests were conducted. The experimental transient cutting force values were compared with the predicted values calculated using the proposed model, and they are found to be in a good agreement with each other.  相似文献   
800.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   
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