吸附-放电等离子体分解去除NOx研究

采用吸附-放电等离子体分解工艺去除NO_x,考察吸附剂类型和放电方式以及循环操作对NO_x去除性能的影响.所考察的4种分子筛(ZSM-5、MOR、SAPO-34和SSZ-13)中SSZ-13具有较大的NO_x吸附容量和较低的吸附强度,有利于延长吸附时间并促进等离子体作用下NO_x的脱附和分解.程序升温脱附和红外光谱分析结果表明,NO_x主要以物理吸附或较弱化学吸附的形式吸附于SSZ-13表面,少量转化为NO₃^-和NO₂^-等强吸附物种.放电方式显著影响等离子体去除SSZ-13表面NO_x的性能,与N₂吹扫放电和封闭放电相比,采用先封闭放电后N₂吹扫放电的方式可同时获得较高的NO_x去除率和去除能效以及较低的NO_x残留率和N₂O选择性.吸附-等离子体分解循环操作时可获得稳定的NO_x去除性能,循环使用6次后SSZ-13晶相和孔结构无显著变化.     

13CO2示踪臭氧胁迫对水稻土壤微生物的影响

本研究采用具有日变化的熏蒸方式,利用13C同位素示踪方法,结合PLFA技术,模拟分析了臭氧浓度升高对水稻土壤微生物结构的影响.实验设置2个臭氧浓度处理,即空气对照(CF,臭氧浓度约4~10 nL·L-1),臭氧浓度升高处理(O3,8 h平均浓度为110 nL·L-1).分别在水稻熏气1个月和2个月时进行13C同位素标记实验.结果发现,臭氧熏蒸一个月的时候对土壤微生物生物量碳没有影响,但此时输入到土壤微生物的即时光合产物13C已经显著低于对照;随臭氧熏蒸时间的延长,无论是总的土壤微生物量碳还是即时光合产物13C对土壤微生物的输入都显著低于对照处理.PLFA主成分分析结果表明,熏蒸一个月时臭氧对13C-PLFA的结构组成并没有显著影响,但熏蒸两个月后则臭氧明显改变了13C-PLFA的组成,但两次标记后PLFA单体的Δδ13C‰值已受到臭氧的影响.臭氧胁迫前期,只有细菌脂肪酸的13C分配(13C%)受到臭氧的明显影响,而胁迫后期则臭氧主要影响的是分配给放线菌和真菌的13C.     

基于禀赋与压力的城市环境综合分区理论与方法研究

环境综合分区是城市环境总体规划的主要任务和落实资源合理利用与生态环境保护空间约束的重要手段.基于资源环境禀赋和压力的环境综合分区理论与方法,在生态功能分区和大气环境、水环境、水资源、土地资源分区基础上,提出城市环境综合分区二级区划方案,以大连市为例进行实证研究.根据综合分区方案,针对资源环境问题和发展现状,细化生态保护红线及产业空间准入线,引导城市资源利用与环境保护,更好地指导城市建设与产业发展.     

Recognising interdependence and defining multi-level governance in city sustainability plans

Abstract

This paper examines the nature of the relationship between sustainable waste management behaviour between the ‘home’ and ‘work’ settings. A questionnaire survey of 566 employees of the Cornwall NHS (National Health Service) was used to examine the nature of the behaviour between the two settings and to understand the main factors influencing the behaviour. The results indicate that there is strong link in the behaviour of individuals between the two settings, with employees who practised recycling activities at home also being more likely to practise a similar behaviour at work. There was also some similarity in the level of sustainability of the behaviour between the two settings. These behaviours were strongly influenced by the underlying attitudes and beliefs of the staff towards the environment. The implications for policy-making to improve sustainable waste management behaviour amongst individuals in England and Wales are also discussed.     

Effects of low temperature on aluminum(Ⅲ) hydrolysis: theoretical and experimental studies

In this study, the effects of low temperature on aluminum(III) (Al) hydrolysis were examined both theoretically and experimentally by constructing a solubility diagram for amorphous aluminum hydroxide (Al(OH)3(am)) and a distribution diagram of hydrolyzed Al species. Firstly, thermodynamic data of Al species at 4℃ were calculated from that at 25℃. A well confirmed polymeric Al species, AlO4Al12(OH)247 (Al13), was involved in building the diagrams and, correspondingly, the non-linear simultaneous equations with 13 degrees were resolved. Secondly, polarized Zeeman atomic absorption spectrophotometry (AAS), 27Al nuclear magnetic resonance (NMR) spectroscopy, and ferron-based spectrophotometry were applied for constructing the practical diagrams. The results show that a decrease of temperature from 25 to 4℃ caused the Al(OH)3(am) boundary on the solubility diagram to shift toward the alkaline side by about 1.0 pH unit and the minimum solubility of Al(OH)3(am) to reduce by 1.0 log unit. The distribution diagram indicates that the monomeric Al, Al13, and solid-phase Al(OH)3 were alternately the predominant species with the increase of pH value during Al hydrolysis. At 25℃, Al13 was the dominant species in a pH range of 4.0 to 4.5, whereas at 4℃, Al13 was the leading species in a pH range spaced from 4.5 to 6.3. The predominant species changed from the monomeric Al to the solid-phase Al(OH)3 over the range of 1.8 pH units at 4℃ in comparison with the range of 0.5 pH unit at 25℃.     

脱硫成本—地面浓度响应模型理论和案例初探

综合分析了目前二氧化硫削减技术政策现状,提出了一种评价二氧化硫治理效率的指标——单位投资地面浓度改善水平。利用该指标对一个地区SO2污染源进行评价,通过设定基金激励机制,吸引高效率的污染源积极完成污染治理任务,并应用博弈论分析基金如何影响企业污染治理决策,达到以较小成本控制污染的目的。通过案例的计算,比较A-P浓度贡献法削减方案和文章推荐方案的脱硫经济成本和环境效益。     

云南白水台现代钙华δ~(13)C的季节和空间变化特征研究

对云南白水台引水渠道中钙华沉积的δ13C值分析发现,白水台引水渠道中钙华δ13C值与降雨量有着较好的线性负相关关系,这一发现为下一步利用当地古钙华的δ13C数据重建古降水量提供了实验与理论基础。而造成雨季钙华δ13C值偏负的原因是雨后形成的低δ13C值的坡面流对高δ13C值的渠道水的稀释效应,降低了渠道水的δ13C值。水中贫13C的CO2逸出至大气是下游方向钙华δ13C偏正的主要原因。     

“十四五”我国VOCs排放总量控制方案研究与建议

我国大气污染防治工作已从以细颗粒物(PM_2.5)控制为主转变为PM_2.5与臭氧(O3)协同控制新阶段,O3已成为空气质量达标和持续改善的重要制约因素。挥发性有机物(VOCs)是生成臭氧的重要前体物之一,大幅削减VOCs的排放量是现阶段O3污染防治的关键。本文基于“十四五”我国VOCs排放的预测结果,提出了VOCs总量控制的总体思路、范围和技术路线,设计了VOCs排放总量控制方案,确定了总量分配指标和指标权重,进一步得出各省(区、市)2025年控制情景下VOCs排放的削减率、削减量以及排放总量,并以此为基础对“十四五”时期VOCs总量控制提出了以区域总量控制为主,结合重点行业、重点企业集群实施总量控制;强化重点行业、重点企业、集群或园区综合治理;建立以环境质量为核心,综合VOCs排放量核查核算及减排绩效评估的考核体系;同时提出了建立市场化的减排机制和舆论监督的实施机制等建议。     

An integrated approach to modeling resource utilization for rural communities in developing countries

Resource consumption in developing countries has been the focus of a considerable amount of research. What has been understudied however, has been the feedback affects of resource consumption on resource availability to both households and communities. Heavy reliance on natural resources and intensive smallholder agriculture common to many rural communities in developing countries has forced people to fulfill short-term needs to the detriment of long-term ecological and livelihood sustainability. This paper introduces a conceptual framework to examine how individuals and households fulfill daily caloric needs and the aggregate effects on resource availability and consumption. Data were collected from a large number of published case studies of rural land-use dynamics, growth and yield models, and human livelihoods were reviewed from scientific journals, reports published by NGOs, and government reports. Using inputs defined by the user, the model tracks annual fuelwood and agricultural land use based on meeting individual energy demands. A case-study-based analysis was patterned after smallholder agriculturalists at the family and community level. Three scenarios are presented in this paper using data from Uganda to illustrate the application of this model.     

天然气供气业务风险分析与应急预案设计

天然气市场需求量的大幅度增加与国内天然气供给不足造成的供需不平衡,给天然气供气业务带来了极大的挑战。根据近两年来天然气供应面临的危机,分别对天然气供气产业链的上、中、下游的突发事件风险进行分析;并针对供气业务中断带来的风险,从突发事件分级、应急处置流程等两个关键要素着手对应急预案进行优化。该研究对完善天然气供气突发事件应急预案、有效快速应对突发事件提供了参考和指导。