因子分析在蒸馏常顶汽油样品PONA分析中的应用

用气相色谱以程序升温方式分析了蒸馏常顶汽油,并将各组分程序升温保留时间转换为恒温保留指数．以各组分在OV-1和SE-54固定相上、同一柱温下的保留指数差及在各柱上的温度系数为三因素进行斜交因子分析,给出了蒸馏常顶汽油样品的PONA值,经色谱－质谱仪分析验证了结果的正确性,为蒸馏常顶汽油样品的PONA分析提供了一种新方法．     

我国燃气汽车标准体系的现状分析与发展建议

以我国现有的燃气汽车标准体系为研究对象,结合我国燃气汽车产业现状和前景,论述了我国燃气汽车标准体系持续健康发展的现实意义和必要性,本文采用查阅资料、调研走访等相结合的方法,对国内现有燃气汽车标准体系的情况进行归纳,对比国际燃气汽车标准体系,分析我国目前燃气汽车标准体系存在的不足与问题,并提出针对性的发展建议。     

BFM2012型柴油机曲轴箱通风系统油气分离器改进

为了改善油气分离效率,降低机油携出量,并维持合理的曲轴箱压力,以BFM2012型柴油机为研究对象,提出了在发动机预分离之后连接一个弥散式油气分离器的新方案,并将新油气分离器与原离心式油气分离器做了对比试验研究.试验结果表明,配备弥散式油气分离器后,活塞漏气量下降1～3 L/min,曲轴箱压力升高40Pa,油气分离效率由原来的53％提高到79％～95％,且不影响加机油的周期,但曲轴箱通风系统阻力增加较明显.     

Estimating the long-term effects of different passenger car technologies on energy/fuel consumption and emissions of greenhouse gases in Europe

Abstract

A stated preference (SP) experiment of car ownership was conducted in Mumbai Metropolitan Region (MMR) of Maharashtra in India. A full factorial experiment was designed to considering various attributes such as travel time, travel cost, projected household income, car loan payment and servicing cost. Data on 357 individuals were collected which resulted in 3213 observations for the calibration of the work trip and recreational trip car ownership models. The car ownership alternatives considered 0, 1 and 2 cars. A multinomial logit framework was used to develop the car ownership model taking the household as a decision unit. The specification and results of the SP car ownership model are discussed. The observed and predicted values matched reasonably when the validity of the SP car ownership model was tested against revealed preference (RP) data. The car ownership models developed in this study exhibit a satisfactory goodness of fit. It is concluded that the SP modelling approach can be successfully used for modelling car ownership decisions of households in developing countries.     

ZnO纳米纤维的制备及其气敏特性研究

应用静电纺丝法制备了Zn（Ac）/PVP复合纳米纤维,经650℃煅烧后得到直径为95 nm的ZnO纳米纤维.分别采用扫描电子显微镜（SEM）和X射线衍射仪（XRD）对ZnO纳米纤维的表面形貌和晶体结构进行了表征.结果表明：ZnO纳米纤维由粒径约30～50nm的微粒组成,为粗糙多孔的网状结构.同时,研究了ZnO纳米纤维传感器的气敏特性.测试结果表明：该传感器在300℃时对低浓度（10 ppm）的乙醇具有高灵敏性和很好的选择性.另外,讨论了ZnO纳米纤维的气敏机制.     

A bi-level model for GHG emission charge based on a continuous distribution of travelers’ value of time (VOT)

Transportation is an important source of greenhouse gas (GHG) emissions. In this paper, we develop a bi-level model for GHG emission charge based on continuous distribution of the value of time (VOT) for travelers. In the bi-level model framework, a policy maker (as the leader) seeks an optimal emission charge scheme, with tolls differentiated across travel modes (e.g., bus, motorcycles, and cars), to achieve a given GHG reduction target by shifting the proportions of travelers taking different modes. In response, travelers (as followers) will adjust their travel modes to minimize their total travel cost. The resulting mode shift, hence the outcome of the emission charge policy, depends on travelers’ VOT distribution. For the solution of the bi-level model, we integrate a differential evolution algorithm for the upper level and the “all or nothing” traffic assignment for the lower level. Numerical results from our analysis suggest important policy implications: (1) in setting the optimal GHG emission charge scheme for the design of transportation GHG emission reduction targets, policy makers need to be equipped with rigorous understanding of travelers’ VOT distribution and the tradeoffs between emission reduction and system efficiency; and (2) the optimal emission charge scheme in a city depends significantly on the average value of travelers’ VOT distribution—the optimal emission charge can be designed and implemented in consistency with rational travel flows. Further sensitivity analysis considering various GHG reduction targets and different VOT distributions indicate that plausible emission toll schemes that encourage travelers to choose greener transportation modes can be explored as an efficient policy instrument for both transportation network performance improvement and GHG reduction.     

Technical innovation vs. sustainability – A case study from the Taiwanese automobile industry

The impact of global warming and climate change is the most critical challenge of the 21st century. The greenhouse effect caused by technological development and industrial pollution has accelerated the speed of global warming. To effectively reduce global warming and encourage sustainable enterprise development, a comparative analysis approach is used to examine various domestic automotive products which utilize the up-to-date innovative technology. Their contributions to fuel consumption and emissions of the greenhouse gas, carbon dioxide (CO₂), are then investigated. This study focuses on technical innovation in a conventional engine and output power. The results indicate that innovative engines (such as the Ford turbo petrol/diesel engine, the EcoBoost/TDCi) have improved energy consumption and CO₂ emissions. In addition, an improvement in output power (such as Toyota hybrid vehicles) has also improved energy consumption and CO₂ emissions.     

舰船排气系统红外抑制装置的湍流场及温度场分析

  目的  为降低通气管航态下的潜艇红外尾迹,  方法  针对柴油机水下排气系统,提出一种能够抑制水下高温废气红外辐射的两级冷却方法,然后基于有限元流体分析方法分析红外抑制前、后的水面温度场。最后,基于仿真得到的初步数据搭建水下排气试验平台,并对红外抑制前、后的水面红外辐射亮度及水下温度进行测试。  结果  结果表明：两级降温措施对柴油机的高温排气有着良好的红外抑制效果,水面最大红外亮度可降低约90%。  结论  该方法对潜艇的隐蔽性改进具有较好的工程应用价值和军事价值。     

燃气轮机高压涡轮叶顶间隙变化规律的有限元分析

高压涡轮叶顶间隙会直接影响到燃气轮机的功率、效率、油耗和寿命。利用有限元等软件,建立了叶片、轮盘和机匣外环的实物模型;通过热结构耦合分析,计算得到各自在温度场和离心力场作用下的径向位移,进而得到叶顶间隙变化规律,并进行了分析。计算结果表明：温度场变化是引起叶片和轮盘径向变形的主要因素;离心力对轮盘径向变形的作用比对叶片径向变形的作用要显著得多;热和离心力变化是间隙变化的两个主要因素;叶片、轮盘和机匣的热响应不一致以及离心力对转子的拉伸作用导致其径向膨胀变形不匹配,进而引起间隙变化;快速增减速度对间隙的影响最为明显。     

油气站场埋地管网腐蚀控制技术

介绍了国内外站场管道的腐蚀情况,并分别从防腐层、区域性阴极保护、在线监/检测角度进一步对比分析了国内外油气站场埋地管道的腐蚀控制情况;从防腐层和阴极保护两方面总结了站场埋地管道腐蚀的主要原因,制订了相应的腐蚀控制对策;并根据国内站场腐蚀的具体情况,从表面处理、防腐材料性能指标、防腐层结构和防腐等级设计几方面对优化站场管道防腐层提出了相应的建议.