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511.
This paper describes a four-year programme of “action research” (AR) undertaken with six communities in the UK, referred to as the Evaluating Low-Carbon Communities (EVALOC) project. The research combined a programme of research events with phased household-level monitoring of energy and carbon-reduction interventions. The carbon-reduction interventions were funded by the UK’s Department of Energy and Climate Change prior to the onset of the research. AR has recently been adopted within the context of environmental behaviour change programmes in the UK, with a number of methodological challenges. The EVALOC project’s challenges included developing a collaborative research design; building reciprocity between the researchers and research participants; dealing with biases and burdens in the research process; ensuring analytical rigour in the interpretation of the primarily qualitative evidence and dealing with the long-term and process-driven outcomes that arise from such interactions. This paper explores and discusses the challenges of AR in relation to selected research outcomes from EVALOC. We conclude by suggesting that the AR approach has helped to build capacity in the participating low-carbon communities (LCCs), through supporting the design, delivery and evaluation of their energy and carbon-reduction activities.  相似文献   
512.
Preference elicitation among outdoor recreational users is subject to measurement errors that depend, in part, on survey planning. This study uses data from a choice experiment survey on recreational SCUBA diving to investigate whether self-reported information on respondents’ comfort when they complete surveys correlates with the error variance in stated choice models of their responses. Comfort-related variables are included in the scale functions of the scaled multinomial logit models. The hypothesis was that higher comfort reduces error variance in answers, as revealed by a higher scale parameter and vice versa. Information on, e.g., sleep and time since eating (higher comfort) correlated with scale heterogeneity, and produced lower error variance when controlled for in the model. That respondents’ comfort may influence choice behavior suggests that knowledge of the respondents’ activity patterns could be used to plan the timing of interviews to decrease error variance in choices and, hence, generate better information.  相似文献   
513.
514.
Different lipophilicity procedures including a newly developed (based on O?cik's equation) was applied in order to compare various urea pesticides with herbicidal and also insecticidal activity, such as monolinuron, chlorotoluron, diuron, isoproturon, linuron, dimefuron, diflubenzuron, teflubenzuron and lufenuron. Lipophilicity parameters (RMWS and RMW0) of nine examined pesticides were determined on the chromatographic plates RP-8F254 with the use of methanol–water as a mobile phase. Similarity analysis enabled to group all examined pesticides depending on their lipophilic character and allowed to perform a more objective comparison of different lipophilicity parameters obtained for investigated compounds by means of thin-layer chromatography and by the use of computational methods. It was stated that with the number of fluorine in examined pesticides, the lipophilic character of insecticides and also their tendency to bioaccumulation in the living systems increases noticeably. The results of this work confirmed that a new procedure for determining the lipophilicity parameter (RMW0) by O?cik's equation could be a suitable tool in the prediction of pesticide bioaccumulation in living system and may be used as an indicator in design of new urea pesticides, which will be safe for humans and the environment.  相似文献   
515.
湿法烟气脱硫液气比的影响因素及参数确定   总被引:2,自引:0,他引:2  
分析了湿法烟气脱硫系统中液气比的影响因素及参数确定,在脱硫系统设计阶段,确定合理的液气比可以提高脱硫效率,降低系统电耗。  相似文献   
516.
化工园区开发建设项目具有建设内容复杂、建设范围大、建设周期长等特点,且不确定性强,产生污染物种类多、数量大,对周边区域的环境影响复杂,其规划环境影响评价应主要依据《开发区区域环境影响评价技术导则》编制。根据化工园区开发项目的环境影响特点,选址、功能区布局、产业规划及可持续发展能力分析作为化工园区规划环评中重点关注的问题,并给予重点评价。  相似文献   
517.
通过对多组源自实验室和工业反应器厌氧颗粒污泥样品主要特征参数的实验室研究和全面的理论分析,对于众多反映颗粒污泥性质的主要参数进行了筛选,在此基础上建立了一组与工业反应器运行状况关系密切且测定方法简便易行、适宜在生产实践中应用的颗粒污泥品质评价参数。所建参数体系能够较好地反映生产操作条件下厌氧反应器的运行状况,并能为高效厌氧反应器的运行控制提供理论依据。  相似文献   
518.
Soil column experiments are used to investigate the fate of three pesticides of high, intermediate, and low solubility in groundwater: N- phosphonomethyl glycine (glyphosate); O,O-diethyl-S-[(ethylthio)methyl]phosphorodithioate (phorate); (2,4-dichlorophenoxy)acetic acid (2,4-D). Feed solutions are prepared by adding each pesticide (100 mg/L glyphosate, 50 μ g/L phorate, 50 mg/L 2,4-D) along with conservative tracer, KBr, in synthetic groundwater. The concentration of the pesticides in effluents is detected by ion chromatography (glyphosate, 2,4-D) and GC-FID (phorate). The Br? breakthrough curves are employed to estimate the dispersion coefficient and mean pore velocity in each column. Solute transport and reactive models accounting for equilibrium/non-equilibrium sorption and biodegradation are coupled with inverse modeling numerical codes to estimate the kinetic parameters for all pesticides.  相似文献   
519.
机械搅拌萃取塔中氯仿萃取DMF的传质系数   总被引:2,自引:1,他引:1  
萃取-精馏法处理N,N-二甲基甲酰胺(DMF)废水是一种节能工艺,相关的工艺研究多有报道.为了对萃取传质过程进行研究,在机械搅拌萃取塔中采用氯仿萃取废水中DMF,在考虑萃取传质系数沿塔高变化的基础上建立了传质数学模型.根据实验数据,结合辛普森积分法和最优化方法一单纯形法对传质模型进行参数估计,获得传质系数与萃取轻重两相...  相似文献   
520.
A/A/O工艺脱氮除磷运行效果分析   总被引:3,自引:0,他引:3  
李曈  郝瑞霞  刘峰  刘京 《环境工程学报》2011,5(8):1729-1734
为提高城市污水处理厂科学运行管理水平和出水质量,通过对某污水处理厂污水处理工艺的沿程采样分析,对比分析了A/A/O工艺脱氮除磷效果与工艺运行控制参数之间的相关关系。结果表明,A/A/O工艺对总氮去除率为83.2%,出水中氮的形态主要为硝酸盐氮;出水中总磷浓度基本达到一级A标准,总磷去除率在86.3%以上;缺氧段具有明显...  相似文献   
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