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991.
结合杭州古新河、西溪河、余杭塘河、备塘河、宁波马蜂港河、横间港河等十余条河道6~7年的持续养护管理经验(河道水质始终保持在V类水及以上),编写了清洁型城市河道养护管理技术标准。该标准简明扼要地概括了城市河道整治后的日常养护管理工作的主要内容、评价指标和适用范围以及技术档案管理系统的建立,为今后政府和相关企业河道养护管理作业提供了有益的参考。  相似文献   
992.
This study investigated the bacterial regrowth in drinking water distribution systems receiving finished water from an advanced drinking water treatment plant in one city in southem China. Thirteen nodes in two water supply zones with different aged pipelines were selected to monitor water temperature, dissolved oxygen (DO), chloramine residual, assimilable organic carbon (AOC), and heterotrophic plate counts (HPC). Regression and principal component analyses indicated that HPC had a strong correlation with chloramine residual. Based on Chick-Watson's Law and the Monod equation, biostability curves under different conditions were developed to achieve the goal of HPC 100 CFU/mL. The biostability curves could interpret the scenario under various AOC concentrations and predict the required chloramine residual concentration under the condition of high AOC level. The simulation was also carded out to predict the scenario with a stricter HPC goal (≤50 CFU/mL) and determine the required chloramine residual. The biological regrowth control strategy was assessed using biostability curve analysis. The results indicated that maintaining high chloramine residual concentration was the most practical way to achieve the goal of HPC ≤ 100 CFU/mL. Biostability curves could be a very useful tool for biostability control in distribution systems. This work could provide some new insights towards biostability control in real distribution systems.  相似文献   
993.
Stormwater runoff has been identified as a source of pollution for the environment, especially for receiving waters. In order to quantify and manage the impacts of stormwater runoff on the environment, predictive models and mathematical models have been developed. Predictive tools such as regression models have been widely used to predict stormwater discharge characteristics. Storm event characteristics, such as antecedent dry days (ADD), have been related to response variables, such as pollutant loads and concentrations. However it has been a controversial issue among many studies to consider ADD as an important variable in predicting stormwater discharge characteristics. In this study, we examined the accuracy of general linear regression models in predicting discharge characteristics of roadway runoff. A total of 17 storm events were monitored in two highway segments, located in Gwangju, Korea. Data from the monitoring were used to calibrate United States Environmental Protection Agency's Storm Water Management Model (SWMM). The calibrated SWMM was simulated for 55 storm events, and the results of total suspended solid (TSS) discharge loads and event mean concentrations (EMC) were extracted. From these data, linear regression models were developed. R2 and p-values of the regression of ADD for both TSS loads and EMCs were investigated. Results showed that pollutant loads were better predicted than pollutant EMC in the multiple regression models. Regression may not provide the true effect of site-specific characteristics, due to uncertainty in the data.  相似文献   
994.
Carbon dioxide(CO2) emissions are a leading contributor to the negative effects of global warming. Globally, research has focused on effective means of reducing and mitigating CO2 emissions. In this study, we examined the efficacy of eco-industrial parks(EIPs) and accelerated mineral carbonation techniques in reducing CO2 emissions in South Korea.First, we used Logarithmic Mean Divisia Index(LMDI) analysis to determine the trends in carbon production and mitigation at the existing EIPs. We found that, although CO2 was generated as byproducts and wastes of production at these EIPs, improved energy intensity effects occurred at all EIPs, and we strongly believe that EIPs are a strong alternative to traditional industrial complexes for reducing net carbon emissions. We also examined the optimal conditions for using accelerated mineral carbonation to dispose of hazardous fly ash produced through the incineration of municipal solid wastes at these EIPs. We determined that this technique most efficiently sequestered CO2 when micro-bubbling, low flow rate inlet gas, and ammonia additives were employed.  相似文献   
995.
英国是世界上较早进行核电建设的国家,有着较长的核电建设历史和良好的核安全纪录。自1995年后,由于对于私有化后的电力市场,英国政府不再为新的核电站建设提供公共部门的支持,以及石油在内的其他能源相对充足等原因,英国的核电建设处于停滞状态。  相似文献   
996.
刘茜 《世界环境》2014,(1):93-93
<正>北京地球村环境教育中心(简称北京地球村)成立于1996年,是一个以传播乐和理念、建设生态文明为宗旨的民间组织。地球村以推动公民参与构建和谐社会、建设生态文明的国家战略为己任,倡导身心境和为内涵的乐和理念,践行以乐和社区与乐和家园为特色的城乡生态社区建设,提供能源及化学品安全等环境教育服务和乐和社工的技能培训,营造以关爱留守儿童、建设农村社区为内容的乐和之家。  相似文献   
997.
声明     
正为适应我国信息化建设,扩大本刊及作者知识信息交流渠道,本刊已被中国学术期刊(光盘版)电子杂志社的中国知网及其系列数据库等检索信息系统独家收录,并以数字化方式复制、汇编、发行、信息网络传播本刊全文,作者著作权使用费与本刊稿酬一次性给付.如果作者不同意文章被收录,请在来稿时向本刊做出纸面声  相似文献   
998.
声明     
正为适应我国信息化建设,扩大本刊及作者知识信息交流渠道,本刊已被中国学术期刊(光盘版)电子杂志社的中国知网及其系列数据库等检索信息系统独家收录,并以数字化方式复制、汇编、发行、信息网络传播本刊全文,作者著作权使用费与本刊稿酬一次性给付.如果作者不同意文章被收录,请在来稿时向本刊做出纸面声明,以便本刊做出适当处理.特此声明!  相似文献   
999.
<正>河口地区是遭受气候变化影响最为严重的区域之一。密集的人口、繁荣的经济使得河口城市根据当地的气候变化威胁制定相应的适应策略变得尤为重要和紧迫。英国伦敦、美国纽约和新奥尔良、日本东京、加拿大温哥华等国际重要河口城市已经制定了详尽的适应气候变化策略,其中有很多有益的经验值得我国的河口城市学  相似文献   
1000.
昆明第一污水处理厂氧化沟工艺至今已运行25 a,随着滇池水环境的恶化,昆明市于2010年将污水处理厂排放标准由原来的一级B标提升至一级A标,总磷的提标是整个提标过程中的重中之重。作者通过对除磷工艺的摸索,研究了除磷加药工艺优化运行的方式,确定了加药量的计算公式,为国内外其他水厂的提标技改,提供技术参考。  相似文献   
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