大气环境影响评价工作分级要求要点

根据大气环境影响评价工作的分级要求,提出了针对性的工作要点,以满足大气环境评价工作的需要.     

抓住机遇打造生态化工城

工业兴市是一个区域经济发展的必然选择,而建设一个绿色生态化工城又是葫芦岛市发展的必由之路.以人为本、科技领先、加强环境保护、推进循环经济发展,以提高城市品位,力争全面达到创建"国家环保模范城"标准,营造一个最适宜人类居住的绿色生态城市.     

城乡接合部居民楼火灾风险评价及防控对策研究

为了准确探究城乡接合部居民楼火灾事故致因机理,预防与控制城乡接合部日常生产与生活过程中引发火灾事故的有效途径,建立信息面更全、实际性更强的火灾风险评估模型是目前行之有效的手段。基于湖南省某地发生火灾事故的实际情况,根据事故树分析法,以城乡接合部居民楼火灾事故为顶事件构建事故树,计算得到事故树的最小割集、最小径集和结构重要度,研究城乡接合部居民楼火灾事故的发生模式、致因因素及影响程度,为改善城乡接合部居民楼火灾安全提供重要的理论依据,并提出相应的防控措施及对策。     

超高强度钻杆低温断裂性能及裂纹扩展特征研究

超高强度钻杆在冬季低温环境下容易发生脆性断裂事故,为了从断裂力学角度揭示其冷脆现象的本质,采用ZBC2302-D型示波冲击试验机,获得了不同温度下超高强度钢在冲击断裂过程中的力-位移曲线,并对比分析了冲击功、起裂功和裂纹扩展功之间的变化关系。采用国家标准GB 4161—2007中的计算公式,计算了冲击试样的裂纹扩展量Δa和阻抗应力强度因子K_R;同时,引入K_R阻力曲线,得到超高强度钻杆在不同温度下的剩余强度图。结果表明,当冲击试样开始出现裂纹时,随温度降低,钻杆的初始起裂应力有所增加,出现硬化现象。当钻杆出现一定长度的裂纹时,随温度降低,阻抗应力强度因子越来越小,而且降低速度越来越快,剩余强度也表现出相同的变化趋势。随温度降低,材料抵抗裂纹扩展的能力逐渐下降,表明钻杆在低温下更容易断裂。     

Optimal Policy Mechanism Design for Cross-Sector and Multi-Stage Pollution Control with a Bilevel Model: Application to SO<Subscript>2</Subscript> Emission in China

In this paper, we construct a multi-stage coordinated programming model under tax system to control SO₂ emission. The model is based on an explicitly formulated SO₂ abatement cost function created under Chinese condition. Analysis of the effectiveness and impact on the economy of the model is carried out with consideration of game theory. By solving the model, theoretical results show that the volume-based multi-stage SO₂ tax system has two properties: effectiveness and equal-rate. Based on these theoretical results, empirical study is also performed using Chinese historical data. Compared with yearly single-stage programming model, the tax rate generated by the coordinated multi-stage programming model is time-invariant and rather moderate in scale. The total abatement cost among planning years in our model is 21.03 % less than the actual number and 6.68 % less than that in the single-stage situation. The tax payment suggested by our model is 10.62 % less than by the single-stage model. In general, a coordinated multi-stage programming model helps reduce the overall costs of environmental protection while achieving the same emission control target with less burden added to the economy.     

煤粒瓦斯瞬时扩散模型研究

为使扩散方程能够准确描述煤粒瓦斯涌出规律,首先依据相似理论和扩散第二定律建立瓦斯扩散系数计算方法,并结合试验数据得到扩散系数与时间的关系。然后基于此构建煤粒瓦斯瞬时扩散球状模型,运用分离变量法对模型进行求解,得到该模型的无穷级数解析解和模型系数的确定方法。最后通过计算值与试验值对比验证瞬时扩散模型的准确性,同时分析瞬时扩散模型与煤体复杂孔隙结构的关系。结果表明:扩散系数随时间的变化符合幂函数递减规律;构建的瞬时扩散模型能够准确描述煤粒瓦斯扩散规律,理论计算高度反映了试验结果;瞬时扩散模型可以从时空角度体现煤粒复杂的孔隙结构。因此该模型可用于计算瓦斯预测参数和研究瓦斯动力灾害形成过程。     

Precursors and potential sources of ground-level ozone in suburban Shanghai

• Air masses from Zhejiang Province is the major source of O₃ in suburban Shanghai. • O₃ formation was in VOC-sensitive regime in rural Shanghai. • O₃ formation was most sensitive to propylene in rural Shanghai. A high level of ozone (O₃) is frequently observed in the suburbs of Shanghai, the reason for this high level remains unclear. To obtain a detailed insight on the high level of O₃ during summer in Shanghai, O₃ and its precursors were measured at a suburban site in Shanghai from July 1, 2016 to July 31, 2016. Using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and concentration weighted trajectories (CWT), we found that Zhejiang province was the main potential source of O₃ in suburban Shanghai. When the sampling site was controlled by south-western winds exceeding 2 m/s, the O₃-rich air masses from upwind regions (such as Zhejiang province) could be transported to the suburban Shanghai. The propylene-equivalent concentration (PEC) and ozone formation potential (OFP) were further calculated for each VOC species, and the results suggested that propylene, (m+p)-xylene, and toluene played dominant roles in O₃ formation. The Ozone Isopleth Plotting Research (OZIPR) model was used to reveal the impact of O₃ precursors on O₃ formation, and 4 base-cases were selected to adjust the model simulation. An average disparity of 18.20% was achieved between the simulated and observed O₃ concentrations. The O₃ isopleth diagram illustrated that O₃ formation in July 2016 was in VOC-sensitive regime, although the VOC/NO_x ratio was greater than 20. By introducing sensitivity (S), a sensitivity analysis was performed for O₃ formation. We found that O₃ formation was sensitive to propylene, (m+p)-xylene, o-xylene and toluene. The results provide theoretical support for O₃ pollution treatment in Shanghai.     

Structural regulation of electroplating sludge by a metal–organic framework synthesis method for an enhanced denitrification activity

Journal of Material Cycles and Waste Management - Electroplating sludge contained multi-metals and organics. In previous reports, electroplating sludges were usually recycled by direct calcination...     

石油降解菌的分离鉴定及4株芽胞杆菌种间效应

通过富集培养和分离纯化的方法,从天津大港油田石油污染土壤和渤海海上钻井平台洗油污水中分离出6株石油降解细菌,生理生化试验及16S r DNA序列分析鉴定表明,它们分别属于Bacillus芽胞杆菌属(S1、S2、S3、S4)、Pseudomonas假单胞菌属(W1)和Ochrobactrum苍白杆菌属(W2),其中,S3具有最高的烷烃(41.3%)和芳烃(30.9%)降解率,从石油污染场地中筛选出的内源微生物对本油田石油的降解效果优于外源物种.对4株芽胞杆菌属菌株构建微生物组进行石油降解实验,结果表明,由S1和S4构成的微生物组F3具有最高的烷烃(50.5%)和芳烃(54.0%)降解率,比单菌降解率分别提高了69.9%和156.1%,同时比最优降解单菌S3的降解率分别高出22.1%和74.6%,而由S2和S3构成的微生物组F4对烷烃和芳烃的降解率最低,分别为18.5%和18.9%,比单菌降解率降低了55.3%和39.0%,实验表明同菌属微生物种间对石油的降解同时存在协同促进和拮抗抑制作用,芽胞杆菌属内亲缘性近的菌株之间对石油降解主要表现为促进作用.     

南京北郊春季气溶胶吸湿性分析

大气气溶胶的吸湿性对气溶胶粒子的谱分布、云凝结核形成、气候强迫、人体健康等均有重要的影响.利用吸湿性串联差分迁移率分析仪(HTDMA)在2014年4月16日~5月21日对南京北郊的大气气溶胶吸湿特性进行观测.30~230 nm气溶胶粒子在90%相对湿度下的吸湿增长观测结果表明,气溶胶粒子的吸湿增长因子平均概率分布函数(GF-PDF)呈现明显的双峰分布,即一个占主导地位的强吸湿模态,和一个相对较小但仍很明显的弱吸湿模态.对吸湿性的日夜对比分析发现,整体上白天的气溶胶粒子吸湿性大于夜间气溶胶粒子,白天强吸湿模态的粒子数目比例高于夜间,夜间气溶胶粒子的外混合程度更高.利用HYSPLIT模式对气溶胶来源分析结果表明,观测期间南京北郊主要受到3类气团的影响.其中西北大陆气团背景下爱根核模态粒子在经过大陆的长距离输送过程后,老化程度较高,吸湿性也更强.而对于积聚模态粒子,则为来自东方气团的粒子吸湿性更强,强吸湿模态粒子数目比例也较高.局地气团背景下气溶胶粒子在各粒径段都具有较高的强吸湿比例.