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81.
Hybrid electric vehicles (HEVs) with low fuel consumption, low emissions, and long driving range are the ideal transition models between conventional fuel vehicles and pure electric vehicles. The growing demand for increased vehicle efficiency has motivated the introduction of waste heat recovery (WHR) technology in the automotive industry, with the organic Rankine cycle (ORC) as the most promising measure for recycling waste energy. Currently, only a few studies have been conducted to couple HEV and WHR systems. These studies have mainly focused on the hybrid powertrain control strategy, but lack quantitative methods to comprehensively analyze the fuel-saving potential due to the WHR system. In this study, an HEV-WHR integrated system that includes a mechanism-based dynamic model of ORC and a hybrid diesel-electric truck model is established. Further, a quantitative evaluation method that simultaneously considers the negative integrated effects (increased vehicle weight and increased exhaust back pressure) and the positive impact values of the engine, motor, and WHR system on the fuel-saving potential is proposed. Finally, the influence of two environmental factors (wind speed and ambient temperature) on the fuel-saving performance is analyzed. The results reveal that under the standard highway driving cycle (HWY), the negative integrated effects reduce the ideal fuel-saving potential of the HEV-WHR system from 6.10% to 5.42%. However, the optimized performances of the engine, motor, and WHR system improve the fuel-saving rate by 0.39%, 1.81%, and 3.22%, respectively. The results also indicate that the fuel-saving potential increases from 1.62% to 8.60% with increasing wind speed and decreases from 6.70% to 4.25% with increasing ambient temperature. 相似文献
82.
Marco Baudino 《Papers in Regional Science》2020,99(4):999-1018
This paper adopts a spatial econometric methodology to investigate the relationship between income and direct household emissions in Italy, as posited by the environmental Engel curve. The spatial approach is motivated by an expanding strand of studies that have detected significant spatial interactions in household-polluting activities responsible for the generation of direct household emissions. Our results suggest the presence of significant spatial dependence for household emissions emerging among regions. At the same time, increases in the level of income do not seem to be coupled with a higher demand for environmental quality by Italian households. 相似文献
83.
本文介绍了西方关于建筑再利用的理论研究和教学概况,以期为国内更好地理解建筑再利用问题以及将来
开展相关研究、教学和项目实践提供些许参考。本文第一部分介绍了建筑再利用的理论研究,从建筑学领域和遗
产保护领域这两个方面分开阐述,建筑学领域关于建筑再利用的理论研究主要分为类型学、技术派、建筑策略和
室内设计等方向,遗产保护领域关于建筑再利用的专门讨论是近几年才开始的,主要包括适应性再利用、可持续
再利用和共同演变式再利用等方向。第二部分介绍了建筑再利用的教学情况,首先以米兰理工大学为例介绍了建
筑学科下关于建筑再利用的专业课程教学,接着以美国罗德岛设计学院和比利时哈瑟尔特大学等高校为代表介绍
了关于建筑适应性再利用的专业硕士培训项目,最后介绍了欧盟关于现代主义建筑再利用以及其他高校关于建筑
再利用的硕士培训项目。 相似文献
84.
介绍了湖州南方物流有限公司中转仓储及输送工程项目的建设背景、建设条件,以及线路规划、主要技术方案,该项目是国内采用长距离越野曲线带式输送机系统运输熟料距离最长的绿色环保工程。项目以电力驱动运输替代汽车运输,日输送量达4.5~5万吨。采用密闭廊道输送,粉尘排放量低,噪声<50dB,日均减少汽车运输3000辆次,年节约燃油2000余吨,减少了尾气排放,缓解了沿线的交通拥堵,实现了良好的经济效益和社会效益。 相似文献
85.
This study optimized the ventilator and furniture location of a tenement unit in a low-income urban habitat to obtain maximum experiential indoor environmental quality (e-IEQ) over the breathing zone. Hypothetical interior layouts using a combination of the two design parameters of ventilator location and bed position were generated for optimizing the design layout. This layout could promote maximum indoor airflow and minimum indoor air temperature and contaminant concentration. In this study, an improved indoor environment is hypothesized to be attainable through improved natural ventilation and thermal performance in the occupied zones. A sequential methodology involving “parametric design modeling–computational simulation–multiobjective optimization–multicriteria decision making”-based framework was selected. Results exhibited that the currently designed tenement unit had a poor indoor environment, whereas the hypothesized iterated layout “optimized design layout, scenario 3 (ODL 3)” derived from the optimization and decision-making algorithm performed effectively in providing e-IEQ. An increase in experiential indoor air velocity by 0.2 m/s and a decrease in temperature by 2 °C were observed over the monitoring point in the ODL 3 considering the existing scenario. Therefore, this study can find a way toward the development of sustainable habitat design guidelines under upcoming slum redevelopment policies across the nation. 相似文献
86.
Mukil V. Ayyasamy Jeroen A. Deijkers Haydn N.G. Wadley Prasanna V. Balachandran 《Journal of the American Ceramic Society》2020,103(8):4489-4497
Density functional theory (DFT) calculations and machine learning (ML) methods are used to establish a relationship between the crystal structures of rare-earth (RE) disilicates (RE2Si2O7) and their coefficient of thermal expansion (CTE). The DFT total energy data predict the presence of several energetically competing crystal structures, which is rationalized as one of the reasons for observing polymorphism. An ensemble of support vector regression models is trained to rapidly predict the CTE as a function of RE2Si2O7 crystal chemistry. Experiments subsequently validated the structure and CTE predictions for Sm2Si2O7. 相似文献
87.
煤炭在促进经济的同时也给生态环境带来了严重的影响,采取有效措施减少煤炭产业对环境的污染,具有很重要的现实意义。为改善环境污染问题,分析了煤炭产业的环境保护问题并提出相应的解决措施。分析认为,需在国家、地方政府、企业层面强化生态环境保护;从提升资源配置、促进煤炭产业转型升级、加强创新驱动等方面促进资源合理开发;需通过制度保障提升科研协作的成效,促进煤炭绿色开采及清洁利用。在注重环保的同时,落实环境一体化产业政策,向环境依存度较低、知识密集型方向发展,可促进行业可持续发展。 相似文献
88.
89.
90.
《中国有色金属学会会刊》2020,30(7):1943-1955
Physicochemical properties of arsenic sulfide sludge (ASS) from copper smelter (ASS-I) and lead−zinc smelter (ASS-II) were examined by XRD, Raman spectroscopy, SEM−EDS, TG−DTA, XPS and chemical phase analysis method. The toxicity characteristic leaching procedure (TCLP), Chinese standard leaching tests (CSLT), three-stage sequential extraction procedure (BCR) and batch leaching experiments (BLE) were used to investigate the environmental stability. The ASSs from different smelters had obviously different physicochemical and environmental properties. The phase composition and micrograph analysis indicate that ASS-I mainly consists of super refined flocculent particles including amorphous arsenic sulfide adhered with amorphous sulfur and that ASS-II mainly consists of amorphous arsenic sulfide. The valence state of arsenic in both sludges is trivalent, but the valence composition of sulfur is quite different. The ASSs have thermal instability properties. The results of TCLP and CSLT indicate that the concentrations of As and Pd in the leaching solution exceed the standard limits. More than 5% and 90% of arsenic are in the form of acid soluble and oxidizable fractions, respectively, which explains the high arsenic leaching toxicity and environmental activity of ASS. This research provides comprehensive information for the disposal of ASS from copper and lead−zinc smelter. 相似文献