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  • [会议] 车内空气污染物的危害及其检测方法的研究
    摘要:汽车车内空气污染源主要有:汽车内饰材料所释放的苯系物质和醛酮类物质;汽车发动机燃烧产物中的一氧化碳、氮氧化物和碳氢化合物;汽车空调系统运行产生的胺、烟碱和车内细菌、可吸入颗粒等。这些污染物会使人产生头疼、头晕、恶心、咳嗽等症状,影响人的心情和注意力,久而久之会引起一些疾病甚至造成死亡。目前,甲醛的测定方法有化学滴定法、分光光度法、色谱法、电化学法、离子色谱法、红外光谱法等,VOCs的方法有气相色谱法、高效液相色谱法、气相色谱-质谱法、荧光分光光度法和脉冲放电检测法等,同时认为有必要加强对汽车企业和广大老百姓的宣传,提倡汽车企业在汽车内饰的研发和生产上采用环保材料。
  • [会议] 汶川MS8.0地震前后龙门山断裂带CO和CH4排气增强
    摘要:地幔流体由C-H-O体系组成(Pasteris,1987),存在一定的CO2、CO和CH4等含碳气体.2008年5月12日汶川MS8.0地震的发生使得沿中央断裂、前山断裂中段和小鱼洞NW向分支断裂分别形成约240、90、7km长的地表破裂带,促使地球脱气作用增强,向大气中释放大量的含碳气体.笔者利用卫星高光谱数据研究了汶川地震前后震中周围及沿断裂带相同面积区域的CO和CH4总量的时空变化及其与地震构造的关系。结果表明:龙门山断裂带地区常年有地下气体沿断裂带向大气中释放,CO沿断裂带释放,受构造控制明显,而CH4除了受构造控制,还受川西地区地下天然气的弥漫式扩散影响;汶川地震的发生促进了地下气体的释放,汶川地震前约1.5个月至震后3个月左右有大量的地下CO和CH4气体沿龙门山断裂带释放到大气中,并且距离震中越近,排气量越大。汶川地震后地表破裂、余震分布特征和利用MODIS数据反演的大气水汽浓度和亮温增高异常受构造控制明显都表明汶川地震引起的地下气体是沿断裂带释放的。这是因为地震孕育中构造应力的加剧作用,沿断裂带及构造盆地出现地下气体的增高异常。研究结果对地震监测、地气交换和环境地球化学监测有重要意义.
  • [会议] 煤气化高层厂房防火设计初探
    摘要:近年来,随着煤化工企业的大型化、工艺的自动化、流程的合理化发展,使得甲类生产厂房煤气化装置超高设计也得到越来越多的应用.但依据《建筑设计防火规范》(GB50016-2006)的第3.3.1条的规定,将厂房的耐火等级、层数和每个防火分区的最大允许建筑面积要求均列为强制性条文,并明确提出甲类厂房除生产必须采用多层者外,宜采用单层.在此种情形下,煤气化高层装置作为煤化工工艺不可缺少的工艺装置,其煤气化甲类高层厂房防火设计探讨便具有了非常重要的实际意义.煤气化甲类高层厂房应按照耐火等级为一级的厂房进行设计,建筑构件采用非膨胀型钢结构耐火涂料进行耐火刷涂保护,使得柱的耐火极限不小于3h,梁的耐火极限不小于2h,楼梯的耐火极限不小于1.5h,使其满足建筑设计防火规范对建筑构件耐火等级为一级的甲类生产厂房的要求。煤气化甲类高层厂房每层及每个防火分区最大允许建筑面积不应大于2500m2,厂房楼层采用通透的钢格板时,其防火分区面积可以不计入所在防火分区的建筑面积内。煤气化甲类高层厂房内电梯井道及楼梯间外墙的耐火极限不应低于2.00h,其梁、柱及支撑的耐火极限应与厂房梁、柱及支撑的耐火极限一致。使用或产生可燃或有毒气体如氢气、一氧化碳、甲醇、氨气等系统单元内,应按区域控制和重点控制相结合的原则,设置可燃气体监测报警探测器,一旦探测器报警,控制室内就会发出声光报警信号,这样就可以早发现早避免灾害事故的发生。煤气化高层厂房应设有室内外消火栓以及消防竖管,与备煤栈桥结合处设有水幕隔断。室外消火栓应沿消防车道边设置并应形成环状,室外消火栓的间距不应大于60m,地下式消火栓应有明显标志,其大口径出水口应面向道路。消防给水干管的管径不应小于200mm。
  • [会议] Assessment of the impact of volatile organic compounds (VOC) on human health in sensitive areas
    摘要:Volatile Organic Compounds (VOC) affect human health in various forms depending on the type of compound (benzene, formaldehyde, etc.). These compounds range from toxic to very toxic, and human health depends on the level and duration of exposure to these toxic pollutants. The adverse effects of long-term human exposure affect kidney and liver, nervous system, and in the case of short-term impacts affect eyes and memory. The purpose of the article is to assess current sensor technologies which allow measuring VOCs concentrations in exposed areas and to analyze the health impacts of vulnerable groups, elderly and children. Measurements are performed using the Libelium sensor. Using relevant statistic indicators on a variate set of measured metrics, we made an appreciation of the correlation between the analysis of value measurement with Libelium sensors installed indoor of a building in two separate rooms and appreciated the relevance of the measured values.
  • [会议] Granular Flow and Heat Transfer Modeling for the Helium Extraction and Acquisition Testbed
    摘要:The helium extraction and acquisition testbed (HEAT) is a prototype volatiles extraction system built to demonstrate a process for acquiring solar wind volatiles such as helium-3 (~3He) from lunar regolith. There are many useful volatiles released from the extraction process being investigated. The ~3He could be used to fuel future fusion power plants that would produce little to no radioactive waste and efficient rockets for Solar System travel. Hydrogen, helium-4, carbon dioxide, carbon monoxide, methane, nitrogen, and water (from hydrogen reduction of ilmenite) are also products of the process. These volatiles could be vital in supporting propellant and/or life support needs of people in space (space stations, Lunar, or Martian outposts) for extended periods of time. In the present research, helium or other volatile gases are implanted into <100 μm JSC-1A regolith simulant using a device called the solar wind implanter (SWIM). The HEAT system is used to extract them by heating the material to 700℃ within a moving bed heat pipe heat exchanger. In this paper, key aspects of the granular flow and heat transfer modeling for the HEAT device are presented.
  • [会议] Flow Analysis of Catalytic Converter - LCV BS III Applications for Optimising Pressure Drop
    摘要:Recently, Indian government enforces stringent control standards for automotive emissions in order to minimise pollution and keep the environment green. To confirm these emission norms, new advanced technologies have been developed in the automotive emissions after treatment systems market. Diesel oxidation catalyst is one of the important contraptions which play a major role in reducing CO and unburned HC emissions. By employing CFD software, the flow properties of catalytic converter can be analysed. This helps to optimise the surface area of DOC, and the effective reaction area is utilised for oxidising the unburned hydrocarbon and carbon monoxide of engine exhaust gases. In the present work, 0.8-litre DOC has been modelled in CATIA V5 software, and CFD analysis was executed by ANSYS CFX software. The pressure drop has been compared by varying the cell density and wall thickness. Finally, the results are compared and the parameters of substrate which give optimum pressure drop are established and concluded. The novelty of the present work is that wall thickness of the porous media substrate, which is in mill inch, has been considered to find out the pressure drop. Calculated pressure drop is verified with engine test bed pressure drop experimental data, before concluding the results.
  • [会议] Study of Separation Between CO with H_2 on Carbon Nanotube by Monte Carlo Simulation in Aluminum Smelter
    摘要:CO is very toxic gas, hence the separation of this gas is very important. In this study, the separation of CO and H_2 has been studied. Prevent the emission of carbon monoxide in the environment is very important. In this study, Lennard-Jones potential was used for gas-gas and gas-carbon nanotube interactions, and the potential parameters for the carbon-gas and carbon-carbon interactions were obtained from the Lorenz-Berthelot combining rules. The study has been done by using the equation state of Virial and finding the second coefficient in Virial equation. Final steps were the inside density, outside density, and total density of nanotubes, and my calculation result shows that this separation is possible.
  • [会议] EXPERIMENTAL AND SIMULATION STUDIES OF CORN KERNEL GASIFICATION IN A DOUBLE AIR STAGE DOWNDRAFT REACTOR
    摘要:Biomass gasification is the devolatilization and incomplete combustion of biomass resulting in the production of a combustible gas mixture including carbon monoxide (CO), hydrogen (H_2) methane (CH_4), and traces of other hydrocarbons (C_nH_m), and referred to as producer gas. Producer gas can be cleaned and then used in various engines or can be converted to various biofuels. This paper presents an experimental and simulation-based evaluation of producer gas quality resulting from corn kernel gasification in a two-stage downdraft gasifier. Test conditions were selected, based on the results of previous studies, to yield high conversion efficiency and low tar production. Experimental tests were performed with an air flow of 25 Nm~3/h and with 80% of the air supplied to the first gasification stage. Simulations based on a chemical and thermal equilibrium model were carried out to examine the effect of equivalence ratio (ER) changes. Both the experimental and modelling results show that using a two-stage air supply leads to a significant reduction in the tar content of the producer gas, while maintaining a high gasification efficiency.
  • [会议] HIGH VOLTAGE PLASMA REACTOR FOR TREATMENT OF CARBON DIOXIDE AND OXYGEN GENERATION
    摘要:High voltage plasma-based technologies have the ability to impact multiple fields from medicine to engineering. The goal of the most recent study was to investigate the efficacy of a novel high voltage plasma system to generate oxygen (O_2) from carbon dioxide (CO_2) through dissociation. The general endothermic plasma-chemical process of CO_2 decomposition is presented, with CO_2 destruction accompanying production of oxygen (and carbon monoxide) at a mole ratio of 2 to 1. A high voltage plasma reactor was developed for this purpose. SEM analysis was conducted on electrodes used for plasma discharges, to better elucidate characteristics of the plasma. CO_2 gas samples were analyzed using an FTIR spectrometer. Baseline scans were taken of CO_2 inside the reactor before plasma power was turned on; subsequent scans were taken after 10 min of plasma treatment. Results of FTIR analysis presented here have indicated a 30% decrease in CO_2 concentration upon application of the developed plasma reactor. This paper reports on various aspects of the instrumented high voltage plasma reactor; and experimental results which further explore the capability to decrease CO_2 concentrations in various environments, while also generating O_2.
  • [会议] Assessment of the impact of volatile organic compounds (VOC) on human health in sensitive areas
    摘要:Volatile Organic Compounds (VOC) affect human health in various forms depending on the type of compound (benzene, formaldehyde, etc.). These compounds range from toxic to very toxic, and human health depends on the level and duration of exposure to these toxic pollutants. The adverse effects of long-term human exposure affect kidney and liver, nervous system, and in the case of short-term impacts affect eyes and memory. The purpose of the article is to assess current sensor technologies which allow measuring VOCs concentrations in exposed areas and to analyze the health impacts of vulnerable groups, elderly and children. Measurements are performed using the Libelium sensor. Using relevant statistic indicators on a variate set of measured metrics, we made an appreciation of the correlation between the analysis of value measurement with Libelium sensors installed indoor of a building in two separate rooms and appreciated the relevance of the measured values.

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