三种厌氧促进剂对亚铵废液厌氧发酵的影响

根据亚铵法草浆蒸煮废液的间歇式厌氧发酵试验结果,分析了活性炭、硫酸亚铁和膨润地亚胺废液厌氧发酵的影响。结果表明,当投量为２．５ｇ／Ｌ时,３４种耨氧促进剂都能显著地促进亚铵废液的厌氧发酵;与对照试验相比,可将厌氧系统的３０ｄ累积产气量分别提高１６．１％、１３．９％和２６．１％。本研究还初步探讨了这３种厌氧促进剂的作用机理。     

国家《大气污染防治行动计划》健康效益评估

为了提高空气质量改善进程,2013 年国家发布了《大气污染防治行动计划》。本文基于空气污染与健康效益评估模型(BenMAP),对人口分布资料、大气污染与人体健康影响的暴露反应关系等进行了本土化修正,采用“支付意愿法”与“疾病成本法”相结合的方法,系统评估了《大气污染防治行动计划》实施后,PM_2.5 污染变化引起的环境健康效益。研究结果表明,《大气污染防治行动计划》的实施将在一定程度上降低PM_2.5 环境浓度,改善环境空气质量。如果《大气污染防治行动计划》空气质量目标全面实现,可以避免城镇8.9 万居民的过早死亡,减少12 万人次住院治疗以及941 万人次的门诊和急诊病例,实现的全国健康效益约为867 亿元/ 年,说明了《大气污染防治行动计划》实施的健康有益性。本文对政府部门开展污染损失评估及制定环境健康政策具有重要的参考价值。     

固体推进剂老化过程影响因素及化学反应机理研究进展

基于固体推进剂的贮存老化,以NEPE推进剂和以HTPB推进剂为代表,综述了近年来固体推进剂老化进程中所受的各种影响因素、作用机制及化学反应机理研究进展。总结了温湿度、应力和环境气氛为代表的外部环境因素,配方性质、组分变化和添加剂等内部影响因素对推进剂老化及贮存失效期限的影响。分别从微观和宏观角度出发,分析了内外部各种影响因素加速或减缓固体推进剂老化进程的作用机制。此外,针对黏合剂、氧化剂、防老剂等化学组分,总结了固体推进剂贮存老化期间发生的氧化交联、分解、降解断链等主要化学反应,并分析了各个反应发生的机理及原因。最后,展望了未来固体推进剂老化影响因素研究的发展趋势,并为今后固体推进剂老化机理及失效模式研究提供了研究思路。     

不同目标导向性规划环境影响评价方法浅析

规划环境影响评价是环境影响评价在规划层次的应用,是对规划或计划及其替代方案的环境影响进行规范、系统、综合的评价过程.就政策导向性和项目导向性规划,从规划环评的方法与程序方面进行了比较、分析,并结合嘉兴滨海新区和巢湖皖维化工基地两个规划环评实例进行了案例研究.     

某水电站库首右岸拉裂变形体形成机理研究

某水电站库首右岸存在一个拉裂变形体,低线施工公路从陡峭拉裂变形体山坡下部通过。低线公路开挖完成后路堑边坡发生局部塌滑,于2003年5月在其上部形成浅层滑坡体(1000多方)。结合拉裂变形体的分析和治理工作,在统计分析大量勘探资料的基础上,提出了该拉裂变形体是边坡在自重应力和构造应力的复合应力场下快速却荷引起岩体的浅表生改造,形成如荷松动岩体,后期在低线公路祠室大爆破开挖施工、下部坡体切脚和基雨的影响下形成浅层滑坡体,并逐步向上扩展的形成机理。     

Determination of types of interactions exhibited by binary mixtures of heavy metals tested against the hermit crab,Clibanarius africanus

Single and joint action toxicity of heavy metal compounds (ZnCO₃, CuSO₄ and CdSO₄) were carried out against the hermit crab, Clibanarius africanus in laboratory bioassays. On the basis of 96?h LC₅₀ values, CuSO₄ (96?h LC₅₀?=?0.03?mM) was found to be the most toxic followed by CdSO₄ and ZnCO₃ (96?h LC₅₀?=?0.24?mM) in decreasing order of toxicity. The evaluation of the metal compounds in mixtures of ZnCO₃–CuSO₄, ZnCO₃–CdSO₄ and CdSO₄–CuSO₄ in pre-defined molar ratios revealed that interactions between Zn–Cu and Zn–Cd test mixtures were in conformity with the models of antagonism (reduction in toxicity of constituent metals). The synergistic ratios (S.R.s) and relationship between observed/predicted 96?h LC₅₀ values (relative toxic unit, RTU) were consistently below 1, indicating antagonistic interactions. Analysis using isobolograms also indicated the interactions between the mixture components to be antagonistic. However, with regards to CdSO₄–CuSO₄ test mixtures, the interactions between these metals were mainly in conformity with the model of synergism. The S.R. and RTU values were largely above 1, indicating synergistic interactions. The importance of the joint action evaluations for the management and protection of aquatic ecosystems, particularly in the setting up of water quality criteria was discussed.     

Restrictions and options: A heuristic tool to integrate knowledge for strategies towards a sustainable development

SUMMARY

This article presents the heuristic ‘Restrictions and Options’ that was created in an interdisciplinary research team to identify restricting and supporting factors regarding sustainable ways of actions for different institutional and individual actors in the need-field of nutrition. The heuristic format is first presented on a general level. Then it is combined with two different approaches: first, with a systemic constructivist approach to organization theory, and second, with the ipsative theory of action (psychology). Its abilities are illustrated by examples from two research projects.

The heuristic tool was developed to help identify relevant factors that restrict or support sustainable development in two empirical settings and also could be used to compare the findings. Combining the two approaches remains for future research.     

Non-timber forest products and village livelihoods in Rajasthan,India: adaptation in a changing environment

This paper presents the results of research conducted between 2009 and 2014 in the village of Khanda Sharol in the state of Rajasthan, India. Our research objective was to determine how the livelihoods of village residents have been affected by the intensification of forest use, and the resulting loss of domestic access to traditionally used forest resources. Results indicate that changes in forest cover have resulted in a loss of livelihood options for village residents. Yet rather than being victimized by environmental change processes, this paper shows how villagers have responded by partnering with public and private actors to develop a community protected forest area that is now helping villagers to meet their livelihood needs. These findings suggest that sustainable livelihoods in rural regions of India require committed and scaled approaches involving local, public, and private actors.     

Cu2+和Cd2+对斑马鱼胚胎早期发育的联合毒性

采用斑马鱼胚胎早期发育技术,测定Cu2+和Cd2+ 2种重金属对胚胎发育的毒性效应. 以24 h致死和72 h胚胎孵化抑制为毒性终点,2种重金属的剂量-效应曲线可用Weibull函数或Logit函数有效描述,由最佳拟合函数计算得出半数致死浓度(LC₅₀)或半数效应浓度(EC₅₀)为毒性效应的评价标准,2个毒性终点的重金属毒性大小顺序均为Cu2+>Cd2+. 应用浓度加和(CA)与独立作用(IA)2种模型,对72 h孵化抑制率的无观测效应浓度(NOEC)配比混合物的联合毒性作用进行了预测,通过混合物试验观测数据的95%置信区间与CA模型和IA模型预测的剂量-效应曲线进行比较分析表明,2种模型都可以有效预测斑马鱼胚胎孵化的联合毒性.      

Examining municipal response to a provincial climate action planning mandate in British Columbia,Canada

The engagement of UK local authorities is vital if national government is to meet its climate change commitments. However, with no mandatory targets at local government level, other drivers must explain engagement. Using a Geographic Information System, this study compares the spatial distribution of action on climate change based on past actions and stated intentions to a suite of relevant independent variables. The Action Index created is among the first to quantify climate change engagement beyond a simple binary measure and provides a useful comparative study to recent work in the USA. The Index enables investigation of both mitigation and adaptation, which show different trends in relation to some variables. The study shows that action is strongest where the voting habits of the local population suggest environmental concern and where neighbouring local authorities are also engaging in action on climate change. Physical vulnerability to the effects of climate change is a motivator for action only where the dangers are obvious. Action is less likely where other resource-intensive issues such as crime and housing exist within a local authority area.