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81.
通过多次的现场调研、收集资料和水质监测,分析了引进天然气净化厂生产的产污环节,现有的污水处理装置的有关设计图纸及污水处理的运行情况.在此基础上,采用理论分析与实际问题相结合的方式,针对现有污水处理过程中的不足,提出了该厂的污水处置适应性改造的可行性研究.  相似文献   
82.
刘媛媛  潘纲 《环境化学》2006,25(1):6-10
水溶液中H-酸通过磺酸基团吸附在TiO2表面,UV照射TiO2所产生的自由基首先进攻吸附在TiO2表面的磺酸基团,从而进一步导致萘环开环.pH 2.5条件下,虽然饱和吸附量较大,但由于H-酸仅通过一个磺酸基团吸附在TiO2表面,过程中产生的硫酸根速率较慢,最终的光降解速率也较慢.pH 5.0条件下,虽然饱和吸附量较小,但由于吸附在TiO2表面的两个磺酸基团同时受到来自TiO2表面自由基的进攻,过程中产生的硫酸根速率较快,最终的光降解速率也较快.吸附模式的差异是导致H-酸在不同pH值条件下光催化降解途径和速率差异的关键因素.  相似文献   
83.
The modern environmental management literature stresses the need for community involvement to identify indicators to monitor progress towards sustainable development and environmental management goals. The purpose of this paper is to assess the impact of participatory processes on sustainability indicator identification and environmental management in three disparate case studies. The first is a process of developing partnerships between First Nations communities, environmental groups, and forestry companies to resolve conflicts over forest management in Western Canada. The second describes a situation in Botswana where local pastoral communities worked with development researchers to reduce desertification. The third case study details an on-going government led process of developing sustainability indicators in Guernsey, UK, that was designed to monitor the environmental, social, and economic impacts of changes in the economy. The comparative assessment between case studies allows us to draw three primary conclusions. (1) The identification and collection of sustainability indicators not only provide valuable databases for making management decisions, but the process of engaging people to select indicators also provides an opportunity for community empowerment that conventional development approaches have failed to provide. (2) Multi-stakeholder processes must formally feed into decision-making forums or they risk being viewed as irrelevant by policy-makers and stakeholders. (3) Since ecological boundaries rarely meet up with political jurisdictions, it is necessary to be flexible when choosing the scale at which monitoring and decision-making occurs. This requires an awareness of major environmental pathways that run through landscapes to understand how seemingly remote areas may be connected in ways that are not immediately apparent.  相似文献   
84.
悬浮填料活性污泥法优化填料投配比试验   总被引:1,自引:1,他引:0  
悬浮填料活性污泥法中试试验系统,利用某城市污水厂生产工艺回流污泥为系统悬浮污泥,探讨了悬浮填料投配比、投配方式和中试硝化效果之间的关系。试验结果表明,悬浮填料最小投配比为15%即可满足系统硝化功能的要求;悬浮填料的投配方式宜采用集中投配并布置于曝气池的末端,这样既可提高系统的生物膜量,又有利于硝化反应的实现。而且,控制适当的溶解氧浓度,悬浮填料的投加有助于同步硝化反硝化更充分的进行。  相似文献   
85.
李贤斌  汪金辉  宋光明  许涛  刘江虹 《安全》2020,(2):73-78,82
为了培养本科生的实践能力、创新能力、团队合作等多项工程核心能力,探索性地将翻转课堂教学模式应用于安全工程专业基础课《燃烧学》教学中。结合问卷调查分析学生自主学习、沟通合作能力,教师信息技术素养、课堂管理能力,结果显示:自主学习能力强及参与度高的学生教学效果良好,期末考评中优秀率上升明显。微视频自主学习在翻转课堂课前学习中占重要地位,但并不是学生最习惯采用的自学方式;教师在课堂氛围、讨论质量及节奏把控方面还需针对性强化。  相似文献   
86.
曹保玉 《环境与发展》2020,(2):53-53,55
海洋陆源污染是陆域经济社会活动行为及其对海洋生态环境造成的负面影响进而出现的污染性问题。累积性的陆源排污不仅会对海洋环境容量造成不良影响,同时也会对海洋自净能力造成减弱影响,不利于沿海地区的经济发展。目前,关于海洋陆源污染问题的防治工作刻不容缓,本文就从多个方面进行统筹规划与科学部署,通过深入掌握海洋陆源污染的具体成因,提出了针对性防治模式,以期为相关人员提供一定的借鉴价值。  相似文献   
87.
近年来,随着中国畜禽养殖业的快速发展,落后的养殖模式和污染防治设施,使畜禽养殖污染日趋严重,畜禽养殖污染已居农业污染源之首,已成为中国环境污染的重要因素,对环境质量乃至人体健康都会产生不良影响。文中采用UASB—SBR组合工艺处理畜禽养殖废水,通过试验探讨SBR反应器启动方法及最佳运行模式,同时研究UASB反应器的启动方法。结果表明,SBR运行的最佳模式为进水0.5 h、反应8 h、沉淀1 h、出水0.5 h、闲置14 h。经过一段时间的启动,UASB和SBR反应器均成功启动,UASB—SBR组合工艺在处理畜禽养殖废水时可获得稳定的处理效果,COD、氨氮、总磷等出水水质均达到《畜禽养殖业污染物排放标准》(GB18596-2001)要求,为畜禽养殖废水处理的工程化应用提供了参考依据。  相似文献   
88.
Failure mode and effect analysis (FMEA), which aims to identify and assess potential failure modes in a system, has been widely utilized in diverse areas for improving and enhancing the performance of systems due to it is a powerful and useful risk and reliability assessment instrument. However, the conventional FMEA approach has been suffered several criticisms for it has some shortcomings, such as unable to handle ambiguous and uncertain information, neglect the relative weights of risk criteria, and without considering the psychological behaviors of decision-makers. To ameliorate these limitations, this paper aims at establishing a hybrid risk ranking model of FMEA via combing linguistic neutrosophic numbers, regret theory, and PROMETHEE (Preference ranking organization method for enrichment evaluation) approach. In the presented model, linguistic neutrosophic numbers are adopted to capture decision-makers’ evaluation regarding the failure modes on each risk criterion. A modified PROMETHEE approach based on regret theory is presented to obtain the risk priority of failure modes considering the psychological behaviors of decision-makers. Moreover, a maximizing deviation model and TOPSIS (Technique for order preference similar to ideal solution) are separately applied to derive the weights of risk criteria and decision-makers. Finally, a numerical example relating to the supercritical water gasification system is employed to implement the presented method, and the effectiveness and feasibility of the proposed model are validated by the results derived from a sensitivity and comparison analysis.  相似文献   
89.
为弥补传统基层应急管理模式的短板,解决信息壁垒、协调困难、公众参与不足等问题。从复合性视角出发,阐述复合治理理论内涵,探讨复合治理与应急管理在主体、思维、过程、空间、目标上的契合性,并进一步分析基层应急管理的现实背景和困境,进而构建基于复合治理理论的基层应急管理模式,阐明模式基本结构和工作流程,最终提出理念树立、平台搭建、机制保障、队伍建设、制度安排、文化营造、技术支撑方面的优化路径。结果表明:复合治理理论的应用可以加强基层应急管理能力,促进多元主体协同共治。  相似文献   
90.
This diary study addresses the benefits of employees' daily use of selective optimization with compensation (SOC) for state work engagement. We hypothesized that day‐level SOC not only directly fosters work engagement but that SOC also reveals its beneficial effects for work engagement in interaction with both external and internal resources. Specifically, we proposed SOC substitutes for job control, role clarity, and state of being recovered, thus helping employees manage low daily levels of these resources. We tested our hypotheses with a sample of 138 employees who completed two daily surveys over a total of 545 workdays. Results of multilevel analyses revealed that SOC benefits work engagement in both proposed ways. First, day‐level SOC was positively related to state work engagement. Additionally, day‐level role clarity and state of being recovered predicted state work engagement, but day‐level job control did not. Second, SOC benefitted state work engagement by offsetting low levels of role clarity and being recovered, and by boosting job control in their respective relationships with work engagement. The results suggest that by using SOC at work, employees can actively enhance their own work engagement on a given workday. This knowledge provides promising starting points for the development of interventions.  相似文献   
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