Emissions impacts of plug-in hybrid electric vehicle deployment on the U.S. western grid

The constantly evolving western grid of the United States is characterized by complex generation dispatch based on economics, contractual agreements, and regulations. The future electrification of transportation via plug-in electric vehicles calls for an energy and emissions analysis of electric vehicle (EV) penetration scenarios based on realistic resource dispatch. A resource dispatch and emissions model for the western grid is developed and a baseline case is modeled. Results are compared with recorded data to validate the model and provide confidence in the analysis of EV-grid interaction outlooks. A modeled dispatch approach, based on a correlation between actual historical dispatch and system load data, is exercised to show the impacts (emission intensity, temporally resolved load demand) associated with EV penetration on the western grid. The plug-in hybrid electric vehicle (PHEV) and selected charging scenarios are the focus for the analysis. The results reveal that (1) a correlation between system load and resource group capacity factor can be utilized in dispatch modeling, (2) the hourly emissions intensity of the grid depends upon PHEV fleet charge scenario, (3) emissions can be reduced for some species depending on the PHEV fleet charge scenario, and (4) the hourly model resolution of changes in grid emissions intensity can be used to decide on preferred fleet-wide charge profiles.     

生物柴油醛、酮类污染物的排放特性与分析

采用2,4-二硝基苯肼(DNPH)衍生法和高效液相色谱(HPLC)技术,对柴油机排气中的醛、酮污染物进行了捕集和分离测定,考察了柴油机燃用BD100、BD50、BD0时,不同负荷下的醛、酮污染物排放规律,分析了燃料组分、缸内温度、压力、排气温度等对醛、酮污染物排放的影响。研究结果表明,该方法可实现微量醛、酮污染物的准确、快速测定;柴油机排气中含量较高的羰基物有甲醛、丙醛、丙烯醛、乙醛、丙酮、丁酮和丁醛,其排放水平均随负荷增大而呈下降的趋势;高负荷时,高温区域的滞留时间延长,醛、酮类被再次氧化、转化几率增加;较高的排气温度会促使排气中的醛、酮类物质和HC燃料再次氧化生成CO和CO2。     

Scenario analysis of China’s emissions pathways in the 21st century for low carbon transition

China’s growing demand for energy – and its dependence on coal – has seen its carbon emissions increase more than 50% since 2000. Within the debate about mitigating global climate change, there is mounting pressure for emerging economies like China to take more responsibility for reducing their carbon emissions within a post-2012 international climate change policy framework. For China, this leads to fundamental questions about how feasible it is for the country to shift away from its recent carbon intensive pattern of growth. This paper presents some general results of scenarios that have been developed to investigate how China might continue to develop within a cumulative carbon emissions budget. The results show how changes in the key sectors of the Chinese economy could enable China to follow four different low carbon development pathways, each of which complies with a cumulative emissions constraint. Each scenario reflects different priorities for governmental decision making, infrastructure investments and social preferences. Having compared the key features of each scenario, the paper concludes with some implications for Chinese government policy.     

A model for the development of a power production system in Greece,Part I: Where RES do not meet EU targets

This paper studies the electricity production system of the Greek Interconnected Electric Production System using a model created with the software package WASP-IV. The period of study is from 2009 to 2030. It consists of three scenarios using three different criteria: energy, environmental and economic. The three scenarios are the business as usual, the lignite and the natural gas. Subsequently, a sensitivity analysis is carried out for the annual growth rate of electricity consumption and load demand. The paper examines how the three criteria change, when there are no other energy sources beyond those already in use (lignite, oil, natural gas, biomass, solar, wind and hydropower) with no CO₂ capture policies and with the electricity production from Renewable Energy Sources not to reach the targets of the European Union for 2020. In a second paper, three other scenarios examine production with the Renewable Energy Sources to reach the targets of the European Union for 2020.     

Partial substitution of hydrogen for conventional fuel in an aircraft by utilizing unused cargo compartment space

Options are being actively sought in aviation to switch from petroleum-based fuels to alternative fuels, of which hydrogen is a promising candidate, despite challenges associated with its production and storage. The possibility is demonstrated in this study of using hydrogen in place of some mission fuel without making substantial aircraft modifications and while utilizing only available unused baggage space in the lower-deck cargo compartments of aircraft. The environmental impact reduction and weight increase are obtained accounting for a broad range of factors including aircraft model, seat capacity, passenger and baggage load factors, annual landing and take off cycles, container type, and costs of metal hydride and gaseous hydrogen storage units of various sizes. It is found that, while there may be a cost increase, CO₂ emissions are substantially reduced, by 25,000–570,000 tonnes annually in several cases and by up to 1.1 million tonnes annually for the 10 types of aircraft considered. It is also determined that with present technology, despite the low density of hydrogen, the weight of storage systems constitutes more of a challenge than their volume in aviation. Large-body aircraft are found to have more difficulties than the narrow-body aircraft regarding storage system weight. For the most frequently used narrow- and large-body aircraft considered, the number of the available containers within the required limits of weight and volume respectively are found to be 3 and 4 for the B 737-800 aircraft and 2 and 10 for the A 340-300 aircraft. Overall, the combined usage of hydrogen and kerosene investigated here may be feasible in the future, but is a challenging option with present technology and aircraft due to various factors.     

5 个费约果品种果实多酚类物质含量及其抗氧化能力比较

以5 个新西兰主栽费约果品种为试材,比较不同费约果品种果实多酚类物质含量和抗氧化能力的差异。结果表明：费约果果实富含多酚类物质,特别是原花青素,且具有较强的抗氧化能力。不同基因型和果实不同部分（果皮、果肉和果浆）总酚、总黄酮、原花青素含量和抗氧化能力均有显著差异。在5 个品种中,“Anatoki”具有最高的总酚、总黄酮、原花青素含量和铁离子还原能力,且费约果果实的果皮积累总酚、总黄酮和原花青素最多,其次是果肉,果浆含量最少。     

回转窑煤粉高效低NOx燃烧的最佳二次风温研究

针对一四通道煤粉燃烧器及φ4.8 m×70 m水泥回转窑,应用FLUENT软件,研究了二次风温对回转窑窑头煤粉燃烧效率、火焰形状以及NOx生成的影响.模拟结果表明,窑内NOx浓度随二次风温增加而显著增加,当风温由1155 K增加至1455 K时,NOx浓度增加了1.73倍.燃用某烟煤,当内外风量比为0.8,空气系数为1.1,煤粉粒径为88 μm时,通过仿真计算得到了火焰形状很好满足煅烧工艺要求的煤粉高效低NOx燃烧的最佳二次风温(T=1255 K).在此温下,煤粉火焰黑火头长1 m,火焰温度为2200 K,窑内烧成长度为12 m,火焰形状好,能很好满足煅烧需要;煤粉燃烧效率高;NOx排放量为390.91 mg/Nm3,符合国家排放标准.实测窑尾烟气温度及各组分浓度与仿真计算结果误差均小于5％.模拟计算结果可靠,为分解窑混煤高效低NOx煅烧水泥窑头操作参数优化提供了依据.     

河南某低品位铝土矿制备β-SiAlON

分别以复合还原剂碳硅、碳铝还原氮化低品位铝土矿(Al2O3含量为68wt％)制备β-SiAlON.利用XRD、SEM和EDS等检测手段和试样的质量变化率,研究了两种复合还原剂制备β-SiAlON的相变过程、β-SiAlON的相对生成量和微观状态.结果表明:低品位的矾土矿利用复合还原剂可以制造出优良廉价的β-SiAlON材料;碳硅试样的β-SiAlON为O'-SiAlON和Al2O3反应生成;碳铝试样的β-SiAlON为AlN、Si3N4和Al2O3反应生成以及碳直接还原氮化莫来石生成;基本结束的反应温度为1500℃,生成的β-SiAlON为柱状、z值为3左右;复合还原剂碳硅还原氮化制备β-SiAlON相对含量高,结晶形貌好,制备成本低.     

四色问题的直观几何论证及单纯性地图四色定理

对地图染色问题的论证已困扰学术界160 余年,根本原因在于它不是经典 数学问题,而人们总想用经典数学方法去证明它。用直观几何方法将其转换为染色等价的正 规地图,并严格证明“相邻域定理”;建立并分析最小单元地图的染色,发现了单纯性和关 联性两种地图染色模式;建立基本单元地图模型,创造由基本单元地图模型成长为地图的过 程与染色相结合的直观方法;严格证明四色定理：任何单纯性地图可以至多用4 种颜色染色, 而任何关联性地图所需颜色数目不确定;创造“缩灭法则”去简化复杂地图;举出了《中国 行政区划正规地图》应用实例。     

机动车排放污染物形成灰霾机制研究进展

机动车排放污染物导致灰霾污染已引起研究者的高度重视,并对此展开了广泛深入的研究.对机动车排放污染物、灰霾污染物的组成、灰霾污染物的来源解析,以及非均相化学过程在灰霾形成过程中的作用进行了综述,总结了近年来机动车排放污染物与灰霾形成关系的研究成果,提出了当前研究中存在的不足及今后研究的发展方向.