湖库富营养化生物控藻技术的研究进展

随着湖库水体污染日益严重,水体富营养化程度不断加剧,蓝藻水华日益频繁,其造成的生态、资源、环境问题以及重大的经济损失已引起高度重视。生物控藻技术主要是通过水生生物调整生态系统群落结构从而抑制蓝藻水华,因其具有效率高、成本低、二次污染风险低等特点,已成为近年来水体富营养化控制技术的研究热点。从生物控藻方面综述了生态浮岛除藻技术、水生植物竞争抑藻技术、滤食性鱼类控藻技术以及微生物溶藻技术等湖库原位控藻技术,总结了国内外在微生物控藻技术方面的最新研究进展,以期为湖库富营养化治理提供理论依据和技术支撑。     

膜法富氧技术对高海拔柴油发动机性能的影响

目的通过膜法富氧技术提高柴油发动机的高海拔使用性能。方法以卷式富氧膜为富氧气体来源,以发动机自身动力为动力来源,设计出富氧装置制造富氧气体。采用并联进气方式,在发动机进气系统增加旁通管路通过富氧装置为发动机补充富氧气体以提高进气的氧含量。通过高海拔发动机模拟台架和高海拔实装试验考察富氧技术对发动机性能的影响。结果高海拔发动机模拟台架试验结果表明,海拔的增加使发动机的高海拔使用性能明显下降,与平原相比,模拟海拔5000 m时,柴油机功率平均下降43.2%,燃油消耗率平均增加74.0%;使用富氧技术后,发动机的高海拔使用性能回复,在模拟海拔5000 m,柴油机应用富氧装置后功率平均提高9.9%,燃油消耗率平均下降8.4%。唐古拉泵站的柴油发电机高海拔实装表明,使用富氧装置后,平均单位发电量油耗下降8.52%。试验过程中,使用了富氧技术的发动机工作稳定、可靠。结论膜法富氧技术运用于柴油机,可有效提高柴油机的高海拔使用性能。     

铅酸蓄电池行业重金属污染治理与环境管理研究

铅酸蓄电池行业是当前重金属污染防治重点行业.研究在分析铅酸蓄电池产业各环节环境影响的基础上,对长兴县铅酸蓄电池行业产业环境整治提升行动进行实例案例分析,总结其成功做法和实践经验.最后,研究得出有效实施开展重金属污染防控的政策启示:积极推动产业集聚和绿色改造、开展绿色生产与技术创新、提升监管措施和管理手段和开展全生命周期环境管理.     

典型城市臭氧污染源贡献及控制策略费效评估

东莞是珠三角O_3污染最严重的城市,使用RSM/CMAQ(曲面响应模型)法分析了珠三角区域人为排放的NO_x和VOCs对东莞市O_3浓度变化源贡献.2014基准年分析结果表明,扣除模型域外区域传输及天然源排放对O_3本底浓度贡献(41.00%)后,东莞本地VOCs排放对O_3贡献最大(18.50%),珠三角区域NO_x减排率13%时可持续降低东莞市O_3浓度.进一步使用ABa CAS-SE(空气污染控制成本效益与达标评估系统)对2017、2020、2025东莞市3个未来年O_3污染控制情景进行了费效评估.评估结果显示,NO_x和VOCs控制比例相对较低的2017年控制情景人体健康效益/区域控制成本比约为1.1;而控制比例相对较高的2025年东莞O_3达标情景效益成本比仅为0.1.这说明,在高减排率情景下,以末端治理为主的控制措施经济可行性较差,需综合采取产业/能源结构调整、清洁生产等措施实现NO_x和VOCs的大比例减排,实现东莞O_3的稳定达标.今后将进一步研究NO_x和VOCs减排对PM_(2.5)环境浓度及健康效益影响,开展多目标污染物协同控制费效评估.     

富里酸红外特征差异与其吸附沥青质行为间关系的研究

通过考察连续碱提富里酸级分的红外光谱及其与沥青质间的吸附行为特征,探讨了富里酸官能团红外特征差异与沥青质吸附行为间的关系。结果表明:连续碱提得到的各级富里酸所含官能团整体组成结构相近,但是在含氧基团和芳香族基团的红外特征上存在较大差异,其红外特征峰面积表现为:一级富里酸>三级富里酸>二级富里酸;随着富里酸中OH基团、芳香基团以及C—O基团红外特征的增强,其对沥青质的吸附速率增大,结合力增强,总体呈正相关关系,而其吸附沥青质展现出的非线性特征愈弱,总体呈负相关关系;适当升温会使吸附特征参数随基团红外特征强度发生变化,分析认为,升温引起的分子热运动增强以及吸附结合强度大小改变可能是导致该现象的主要原因。     

极低放核废物处置安全评价概述

放射性废物处置受到很高程度的关注和重视;极低放核废物处置系统的定量预测需要对其进行安全评价;本文就极低放处置场的安全评价现状进行了概述,主要介绍了目前我国主要采用的景象后果分析方法。     

Simulating spatiotemporal dynamics of urbanization with multi-agent systems—A case study of the Phoenix metropolitan region, USA

Urbanization is a human-dominated process and has greatly impacted biodiversity, ecosystem processes, and regional climate. To understand the socioeconomic drivers of urbanization and project future urban landscape changes, multi-agent systems provide a powerful tool. We develop an agent-based model of urban growth for the Phoenix metropolitan region of the United States, which simulates the behavior of regional authorities, real estate developers, residents, and environmentalists. The BDI (Beliefs-Desires-Intentions) structure is employed to simulate the agents behavior and decision models. The heterogeneity of agents is reflected by adjusting parameters according to the agents’ beliefs, desires and preferences. Three scenarios, baseline, economic development priority and environmental protection, are developed and analyzed. The combination of multi-agent system and spatial regression model is employed to predict the future urban development of the Phoenix metropolitan region. Landscape metrics are used to compare the spatial patterns of the urban landscape resulting from different scenarios in different times. In general, with the rapid urban expansion, the shape of urban patches will become more regular as many of them become coalesced. The spatial analysis of urban development through modeling individual and group decisions and human-environment interactions with a multi-agent systems approach can enhance our understanding of the socioeconomic driving forces and mechanisms of urban development.     

Carbon dioxide capture under ambient conditions using 2-chloroethylamine

This is the first case applying 2-haloethylamine to CO₂ capture. The prospect of global warming and the urgent need to reduce atmospheric concentration of carbon dioxide has prompted actions at many levels. The conventional capture of carbon dioxide is predominantly based on chemical absorption using ethanolamine. Recent developments of carbon dioxide capture focus on new materials, such as ionic liquids, zeolites, membranes, carbonaceous absorbents, and metal–organic frameworks. However, no unique solution exists currently to solve the problem of carbon dioxide capture. In order to examine the efficiency of 2-chloroethylamine as an absorbent of CO₂, we treated an aqueous solution of 2-chloroethylamine hydrochloride with CO₂ in the presence of an alkali, e.g., NaOH, under ambient conditions. The absorption was complete within 30 min, seemingly following first-order reaction kinetics. Furthermore, we succeeded in capturing CO₂ from ambient air using 2-chloroethanolamine. The efficiency of 2-chloroethylamine as an absorbent of CO₂ could be attributed to the production of stable 2-oxazolidinone, therefore, this reaction is favored thermodynamically. Compared with previously reported absorbents, this novel system is capable of capturing CO₂ with an extremely high efficiency of 1 mol per mol absorbent under ambient conditions, even from the atmosphere. This potential method could be used to capture CO₂ particularly from small, mobile, or low-concentration emission sources.     

南京老山国家森林公园朴树种群动态

运用相邻格子法对南京老山国家森林公园朴树(Celtis sinensis)种群(以下简称老山朴树种群)进行野外调查,以定量方法研究其种群结构特征。编制种群静态生命表,并绘制存活曲线、死亡率曲线、消失率曲线和4个生存函数曲线,同时结合时间序列预测模型研究老山朴树种群的数量动态。结果表明,种群各龄级个体数虽然存在波动,但整体呈增长趋势,存活曲线属DeeveyⅡ型,分别在第Ⅰ和第Ⅶ龄级出现2个死亡率高峰。第1个峰值的出现主要是由于种内竞争激烈,第2个峰值伴随种群进入生理死亡年龄而出现。生存分析结果表明,朴树种群至第Ⅵ龄级时,生存率仅为0.5%,累计死亡率高达99.5%;危险率曲线与死亡率和消失率曲线变化情况基本一致,反映朴树种群生长发育过程具有前期薄弱、中期稳定、后期衰退的特点。时间序列预测结果表明,在未来的2～6 a内,老山朴树种群呈增长趋势。对幼苗及幼林进行人工抚育管理将有助于老山朴树种群的天然更新。