一种新的扇区拥挤告警指标及应用

针对我国管制扇区日益繁忙拥挤、空管保障系统的相对落后,扇区流量告警机制尚不健全的现状,在分析和研究美国、欧洲、日本扇区流量告警机制基础上,提出当量流量告警指标的概念;采用MMBB工作负荷评估方法确定不同特征航班对应的当量系数,计算出扇区的当量流量,建立一种新型的扇区流量告警方法;应用算例的结果验证了当量流量告警指标在扇区流量告警工作中的有效性和实用性。     

基于回归分析的火灾发生气象因子的研究

利用二元回归分析法,对火灾发生次数、空气湿度、风速进行回归分析并检验,得出了火灾发生次数、空气湿度、风速三者之间的显著线性关系。     

Time and cost characterisation of emissions from non-road diesel equipment for infrastructure projects

The construction process contributes to pollutant emissions, particularly through the operation of diesel- and gasoline-powered equipment. In the past decade, a series of investigations were undertaken to quantify these emissions for a variety of non-road construction equipment performing different activities and undergoing different duty cycles, and a model to estimate quantities of six types of pollutant was developed. This paper uses that model to estimate emissions for four street and utility construction projects which no one has done previously. We combined information from company records with standard construction industry manuals to estimate total emissions for the projects and to examine the pollution patterns and magnitudes. The street construction projects all had similar emission profiles with a large peak at the beginning and a steady output of emissions throughout the duration of the project. For example, in two of the projects studied, half of all CO₂ emissions were produced before the projects were 40% completed. Results showed that demolition and earthwork are the activities with the largest contribution. The equipment types with the largest contribution are backhoes, front-end loaders, bulldozers and trenchers. Trenchers, for example, produced 30% of all emissions on the projects on which they were used.     

Occurrence of benzotriazoles (BTRs) in indoor air from Albany,New York,USA, and its implications for inhalation exposure

Despite the widespread use of benzotriazoles as corrosion inhibitors in many household goods, studies on the occurrence of these compounds in indoor air are scarce. In this study, five benzotriazole derivatives were measured in 83 indoor air samples collected from various locations in Albany, New York, USA. Benzotriazoles were found in a majority of the indoor air samples, and the concentrations of their sum in bulk (vapor plus particulate phases) indoor air ranged from below the method limit of quantification to 492 ng·m^?3 (geometric mean: 5.8 ng·m^?3). The highest geometric mean concentration was found in air samples collected in parking garages (155 ng·m^?3), followed by barbershops (13.6), public places (11.5), auto repair shops (5.2), automobiles (4.5), homes (4.5), offices (3.7), and laboratories (2.8). Inhalation exposure to benzotriazoles was calculated on the basis of the measured geometric mean concentrations and air inhalation rate. The highest exposure dose was found for teenagers, with a geometric mean inhalation exposure dose of 79 ng·day^?1. The body-weight normalized exposure dose, however, was the highest for infants, at 3.2 ng·(kg bw)^?1·day^?1.     

The channels of the effect of government expenditure on the environment: evidence using dynamic panel data

This paper explores the relationship between government spending and environmental quality using panel data for 94 countries for the period 1970–2008. We identify and estimate three distinct channels that comprise the total direct effect of government expenditure on air pollution, namely a marginal effect, an effect conditional on economic growth and an effect conditional on institutional quality. Since adjustment rate of emissions to their equilibrium level is slow due to technological and institutional reasons, we explicitly take into account dynamics by applying appropriate econometric methods. The results demonstrate that there is a significant alleviating direct effect of government expenditure on SO₂ and NO_x emissions, which increases with the level of economic growth and democracy. However, there is no evidence of a significant effect on pollutants with more global impact on the environment and human health, like N₂O and CO₂, implying that the adoption of international environmental treaties is required in this case.     

Local air pollution and global climate change taxes: a distributional analysis for the case of Spain

Global climate change measures are difficult to implement. In this context, local air pollution measures may play an important role in the political agenda since their effects are felt more immediately by citizens. Distributional implications are one of the main barriers for implementing environmental policies. This paper explores the distributional implications of air pollution taxes and compares them to climate change taxes. For the comparison, both tax schemes were set to yield the same revenue. Methodologically, the study uses a top–down approach linking a macro model to a micro model. We find that taxes on local air pollutants are more regressive than those levied on CO₂. This is because the goods implicitly taxed have a greater weight in the consumer basket of low-income groups, even if the tax revenues are recycled. Furthermore, the revenue-neutral recycle scheme increases both taxes efficiency, but, at the same time, can increase regressivity.     

胶合竹材GluBam甲醛释放影响因素的气候箱实验与分析

胶合竹材GluBam的甲醛释放情况是现代竹结构住宅环保性的一个重要方面,也是竹结构住宅推广中最受关注的指标之一。采用1 m3气候箱对温度、相对湿度和封边情况与GluBam的甲醛释放量和释放速率的相关关系进行了测试,并以一阶单衰减模型为基础提出了GluBam的甲醛释放分析模型。测试和分析结果表明:GluBam板材在各模拟条件下甲醛浓度峰值均小于规范要求;初始甲醛释放量E0和衰减率常数k可以用来评价GluBam的甲醛释放特征;GluBam的醛释放量和释放速率随环境温度和湿度增加而显著增大,且温度因素的影响更大;封边处理可以有效降低GluBam板材的甲醛释放量。     

Visualization and localization of bromotoluene distribution in Hedera helix using NanoSIMS

Some plants are known as indoor air purifiers. A large number of studies report kinetic purification results for an extensive panel of plants, i.e. the pollutant concentration (volatile organic compounds, as known as VOC, most of the time) is continuously monitored by gas chromatography. However, only a few papers describe the mechanisms involved in such processes. This study deals with the use of secondary ion mass spectrometry imaging as an efficient tool to locate atmospheric pollutant as bromotoluene within the Hedera helix plant (leaf, roots) and the substrate on which it was previously grown. Hedera helix plants have been placed in a pollution chamber with control of the exposure parameters. Plant and soil samples excised were transferred into a fixative solution of glutaraldehyde and paraformaldehyde for a few days, were dehydrated using ethanol and were embedded with resin. Cross sections were made from the pale brown solids obtained. Then, a device using a cathodic pulverization device capable of depositing a few nanometers of gold atoms over the sample was used to make the surface electronically conductive for the NanoSIMS. Hence, polluted and unpolluted samples of Hedera helix and substrates were obtained following a careful procedure that allowed for the discrimination between polluted and nonpolluted ones. Nanoscale spatial resolution was an invaluable tool (NanoSIMS) to achieve this, and proved that VOCs, such as bromotoluene, were actually trapped by plants such as Hedera helix.     

Multi-step approach for comparing the local air pollution contributions of conventional and innovative MSW thermo-chemical treatments

In the sector of municipal solid waste management the debate on the performances of conventional and novel thermo-chemical technologies is still relevant. When a plant must be constructed, decision makers often select a technology prior to analyzing the local environmental impact of the available options, as this type of study is generally developed when the design of the plant has been carried out. Additionally, in the literature there is a lack of comparative analyses of the contributions to local air pollution from different technologies. The present study offers a multi-step approach, based on pollutant emission factors and atmospheric dilution coefficients, for a local comparative analysis. With this approach it is possible to check if some assumptions related to the advantages of the novel thermochemical technologies, in terms of local direct impact on air quality, can be applied to municipal solid waste treatment. The selected processes concern combustion, gasification and pyrolysis, alone or in combination. The pollutants considered are both carcinogenic and non-carcinogenic. A case study is presented concerning the location of a plant in an alpine region and its contribution to the local air pollution. Results show that differences among technologies are less than expected. Performances of each technology are discussed in details.     

地下停车库空气污染物排放实测研究

通过对上海市某商业地下停车库库内及排风管道的连续监测,获得了CO、NO、非甲烷总烃(NMHC)、PM10等空气污染物浓度数据。结果表明:(1)地下停车库的休息日车流量明显大于工作日,且工作日小时车流与车位比为20%~50%、休息日小时车流与车位比为20%~80%。(2)总体上,地下停车库内CO、NO、NMHC浓度呈明显变化规律,营业时间现峰值,非营业时间现谷值;地下停车库内CO、NO、NMHC变化规律和车库排风中具有较好的一致性。(3)车库排风中污染物浓度水平均低于地下停车库内。(4)营业时间的CO、NO、NMHC小时浓度平均值明显增大,约为非营业时间的2.42~3.67倍。(5)单车次CO、NOX、NMHC排放量最大值分别为0.855、0.070、0.214g/(辆·次)。(6)营业时间,除地下停车库内CO外,NO、PM10的8h时间加权平均值符合《工作场所有害因素职业接触限值化学有害因素》(GBZ 2.1—2007,其中未规定NMHC)中时间加权平均容许浓度(PC-TWA);地下停车库内CO出现33.3%的超标频率,最大占标率104%。