Levels of black carbon and their relationship with particle number levels—observation at an urban roadside in Taipei City

Information on the relationship between black carbon (BC) and particle number levels in urban areas is limited. Therefore, investigating the relationship between BC and particle number levels in different particle size ranges at an urban area is worthwhile. This study used an aethalometer and scanning mobility particle sizer to measure the levels of BC and particle number simultaneously at an urban roadside in Taipei City. Measurement results show that hourly BC levels are 0.62–8.80 μg m^?3 (mean?=?3.50 μg m^?3) and hourly particle number levels are 4.21?×?10³–4.64?×?10⁴ particles cm^?3 (mean?=?2.00?×?10⁴ particles cm^?3) in Taipei urban area. The BC and particle number levels peak during morning (7:00–9:00) and evening (16:00–18:00) rush hours on weekdays. Low BC and particle number levels exist in the early morning hours. Time variations in BC levels are the same as those of particle number levels in this study, clearly indicating that BC and particles are likely released from the same emission source. Additionally, BC levels in the urban area are more strongly associated with ultrafine particle levels than with total particle number levels, particularly in the size range of 56–180 nm. According to measurement results, most BC in aerosols in urban areas can be in the ultrafine size range.     

我国矿产资源国家所有权的价值考量

我国经济高速发展的同时,出现了矿产资源大量消耗和环境严重污染的问题。许多学者认为是矿产资源国家所有权惹的祸,极力倡导所有权改制。从理性的角度出发分析,出现这种现象并不是国家所有权惹的祸,而是国家所有权的管理体制不再适应今天市场化的要求,应从管理体制和竞争方面来加强矿产资源的管理。     

Theoretical and Empirical Analysis on Influence Factors of Modern Agricultural Equipment Level in the Processof Agricultural Sustainable Development

To promote modern agricultural equipment level is one characteristic of constructing and developing modern agriculture in China.This paper makes up stepwise linear regression analysis model of influence factors of modern agricultural equipment level,and chooses rural labor,per capita income of rural residents,rural investment,proportion of people at secondary education level and at higher level in per hundred rural labor force and arable land area as independent variables,and total power of machine as induced variable.The major results show that the relativity of modern agricultural equipment level,rural investment and education level of peasants is remarkable,and they are the major influence factors of modern agricultural equipment level.Raising investment level of rural infrastructure construction as well as and research and development and promotion of advanced and applicable modern agricultural equipment,improving quality and education level of peasants can accelerate the development of China’s modern agricultural equipment effectively in the process of agricultural sustainable development.     

Aquatic photolysis of hydroxylated polybromodiphenyl ethers under direct UV irradiation: a case study of 2′-HO-BDE-68

Environmental Science and Pollution Research - Hydroxylated polyhalodiphenyl ethers (HO-PXDEs) have attracted considerable scientific interest as examples of emerging aquatic pollutants. However, a...     

四川酸性物湿沉降模式及预测

酸沉降是一复杂的大气物理和化学过程，涉及诸多复杂影响因素。目前，我国酸雨湿沉降模式还仅限于模拟云下洗脱成酸过程，而对云中的成酸过程还未进行深入研究，这不仅在理论上不完善，而且更重要是在许多情况下与我省实际情况不符。本课题针对四川省特定的地理，气象特点和严重的大气污染情况，并借鉴国外研究成果，提出了考虑酸性沉降的云中和云下成酸过程和各种影响因素的综合酸雨湿沉降模式，并根据此模式来估算和预测四川省酸雨     

试用模糊数学方法对电焊作业防护措施进行综合评价

选择北京市四家锅炉厂的电焊工５６名，即从事手把焊、氩弧焊、ＣＯ２气体保护焊、电弧气爆等特种工种作业人员。通过调查，提出单项四级评分标准，再依模糊数学模型，进行综合评价。按Ｂ＝Ａ·Ｒ，求得Ｂ中最大元为０．７０７。最后总评为甲级。此结果与权数分配有关。此方法，可为劳动卫生管理（防护措施评级）提供依据。     

钻井废水的处理

本文针对钻井废水的处理，综述了现有的处理方法、处理药剂以及处理装置，并对钻井废水的处理、排放提出了一些意见和建议。     

燃烧风洞测试系统概况及设计思想

本文介绍了燃烧风洞中测试设备的概况和设计思想。该装置功能包括：测量风洞试验段入口的各种流体和热力学参数、试验段的温度分布、火焰几何参数以及火焰前锋跟踪设备、高速数据采集系统和数据处理软件。本系统能满足各类林火蔓延规律实验研究的需要．     

燃烧风洞的研制及其燃烧特性研究

本文介绍了为可燃物燃烧特性研究而建立起来的模拟自然环境条件的燃烧风洞设备以及在燃烧设备中进行的模拟火场的火蔓延特性研究。在燃烧风洞中进行的可燃物燃烧实验为林火机理的研究、火蔓延模型的建立提供了实验依据．     

绵阳市大气降水pH值时空分布及酸雨成因研究

通过对绵阳市9个测点1998－1999年大气降水监测数据的统计分析，并结合历史数据，对大气降水pH值的时空分布及酸雨成因进行了研究。结果表明：绵阳市大气降水酸化严重，除主要受本地区大气污染影响外，还受大气中、长距离输送的影响。