北京市部分区域市政末梢饮用水在线监测结果分析

目的通过在线监测数据,描述北京市2014年生活饮用水水质总体情况,分析各地区水质、水厂及供水管网特点,为卫生监督部门制定监管方案、优化在线监测系统提供参考。方法收集2013年12—2014年10月北京市不同区域7个市政水厂附近在线监测点的管网末梢水监测数据,整理为日平均值后进行统计分析,从数据有效性、月均值、日均值、地区差异等角度,对pH、浑浊度、余氯、电导率和总有机碳(TOC)五项指标进行综合分析比较。结果经统计学分析,各监测点的五项指标数据有效,日均值均有统计学差异。丰台区、大兴区的监测点位于南水北调水源地切换点,电导率变化趋势与水源切换时间相符。结论北京市城区市政管网供水监测点水质监测指标符合标准要求,市政水厂及供水管线中全年水质波动平稳。在线监测系统稳定性较好,通过各参数的实时监测能从一定程度上反映管网中水质变化,可进一步完善综合分析能力,普及推广。     

NaClO消毒条件下供水系统余氯指标控制的优化

以天津滨海新区某区域供水系统为研究对象,对次氯酸钠(NaClO)代替液氯消毒后引起的出厂水水质变化和供水管网余氯变化进行了分析,以实现对NaClO消毒工艺运行参数的优化控制。结果表明,NaClO代替液氯消毒仅导致出厂水的p H值略有增加;当NaClO平均投加量达到20 mg/L左右时,出厂水余氯范围可保持在0. 70~0. 90 mg/L,管网末梢余氯均满足≥0. 05 mg/L的国家标准要求;对长距离供水区域可采取单独补氯消毒,补氯后出厂水余氯范围应保持在0. 90~1. 10 mg/L,可有效提高该区域的管网末梢余氯。     

江西省2011—2012年城市生活饮用水水质分析

目的分析江西省2011—2012年城市生活饮用水水质状况,为保障城市居民饮水安全提供科学依据。方法分别在2011—2012年选取部分城市的市政供水、集中供水、二次供水单位作为监测对象,采集出厂水、末梢水和二次供水的样品进行检测、评价。结果 2 a共采集水样3 777份,总体合格率为92%,二次供水不合格的指标有总大肠菌群、菌落总数、氨氮、浑浊度、pH、游离氯、二氧化氯;集中供水不合格指标有总大肠菌群、菌落总数、浑浊度、pH、铝、铁、游离氯、七氯;部分城市管网老化腐蚀可能影响末梢水水质。结论市政集中供水水质好于自建集中供水和二次供水;对城市所有供水单位的监督管理亟待加强。     

澳门城市供水系统的水质保障措施

如何根据实际条件，选择经济实用的技术来保障甚至提高供水水质，已经成为中小规模城市供水系统共同面临的问题。澳门自来水有限公司多年来在这方面积累了一定的经验。根据水质和工艺情况，选用合适的助凝剂，有效地提高了对藻类的去除并显著降低了出厂水浊度。另外，较高的管网余氯有效地控制了管网水水质。多年运行实践表明，出厂水浊度可以稳定地控制在0．1NTU左右，管网末梢细菌总数基本低于10个／mL。     

某省城市供水末梢水合格率高于出厂水原因分析

目的探讨城市供水末梢水合格率高于出厂水的原因。方法以2014年某省城市供水水质监测结果为样本,按照供水能力,将水厂分为3组,分别为:<10 000 t/d、(10 000~50 000)t/d以及≥50 000 t/d,计算每组水厂的出厂水、末梢水合格率。结果分组前出厂水合格率低于末梢水合格率,分组后3组水厂的出厂水合格率均高于末梢水合格率。结论比较出厂水以及末梢水合格率时,应根据具体情况分组、分类计算,从而消除因为出厂水、末梢水采样比例的不确定可能带来的影响。     

供水管网余氯偏低的问题分析

以天津某水厂为例,针对管网余氯偏低的情况,分析了水厂近3年加药量,出厂水和管网水余氯、氨氮、氯氨比,以及管网水亚硝酸盐的变化规律。对管网余氯和氨氮的相关性分析结果表明,两者之间有明显的正线性相关关系,在只增加出厂水余氯含量的情况下,由于管网中硝化反应的发生,使氨氮含量降低,从而导致管网余氯偏低。     

水质模型在提高管网余氯措施模拟中的应用

以郑州市现状水力模型为基础,对软件水力追踪和水质模拟功能进行开发及应用,可实现管网水龄计算、余氯衰减模拟、供水区域追踪等功能。建立管网余氯模型,可模拟管网中余氯的总体水平和变化情况,可为南水北调通水后管网"黄水"控制措施的制定提供重要依据。通过模拟以及结合研究成果预测水质风险区,可提高应对水质风险能力。同时,可根据管网水中余氯衰减情况和管网末梢的余氯水平,指导水厂加氯量。     

水厂水质净化及水质管理体验谈

黄洲水厂是“全国农村百佳水厂”、“全国农村优秀水厂”。自投产十四年以来出厂水平均浊度是0．15NTU，多数在0．1～0．2NTU之间，有时在0．INTU以下。管网水浊度平均0．5NTU，供水合格率达到100％，各项指标远优于国家饮用水卫生标准。我们采取的措施如下：     

长距离给水管网氯胺消毒的控制研究

以某市第二水源工程供水管网为研究对象,通过测定余氯和茵落总数,考察了氨、氯质量比和出厂水余氯浓度对长距离给水管网氯胺消毒效果的影响。结果表明,在氨、氯质量比为1：4．5时,通过适当提高出厂水余氯浓度,可以有效改善长距离输水管网中的水质,避免增加中途加氯设备,以及便于水厂管理。     

高温、原水富营养化造成水厂制水、管网供水余氯大幅衰减的原因与对策

杭州九溪水厂技术人员经过三年的运行实践，对夏季高温时原水富营养化造成出厂制水、管网供水余氯大幅下降现象进行分析，提出相关对策，对水厂技术人员有一定的借鉴作用。     

浅析高速公路工程招投标中的最低评标价法

结合目前高速公路施工项目招投标活动的实际情况,阐述了最低评标价法的概念,归纳了其优点及存在问题,对完善最低评标价法提出几点策略,以期促进招标投标市场更加规范有序。     

Place-Making in Megaprojects in Melbourne

This article analyses state-led place-making practices in Melbourne. The two levels of government that influence planning in Melbourne make much of the city as ‘culturally vibrant’ and ‘creative’, and have incorporated creative city-inspired place-making principles into many layers of the planning system. An examination of the development of two mixed-use megaprojects in central Melbourne reveals however that ideals of culturally engaging public places, and indeed of creative landscapes for middle-class consumption, wither in the face of more basic imperatives for economic development. In these case studies the ‘creative city’, no matter how the idea is interpreted, has little traction either as a set of inclusive place-making principles or as a gentrification strategy. The article concludes that the creative city-inspired place-making objectives in the planning system at both state and local levels are ambiguous in their overall intents and completely unsupported by statutory controls. Such place-making objectives as are realised are the compromised results of the interplay of uncoordinated decisions, delivered at the pleasure of the developer.     

Pathogens in septage in Vietnam

Septage is widely acknowledged as a major source of infectious pathogens while disposal of septage, and the operation and maintenance of septic tanks, is not regulated in many developing countries. Twenty untreated septage and septage sludge samples were taken from Can Tho City, Vietnam to examine their pathogen content, and indicator micro-organisms. Escherichia coli and Enterococcus spp. were detected in all samples, regardless of sludge storage time. Phages were detected in 80% of samples. Salmonella spp. were detected in 70% of the untreated septage and 60% of septage sludge samples. Concentrations of phages and bacteria tested in septage sludge after many years of tank storage were much higher than the expected levels. Helminth ova were present in 95% of untreated septage samples with an average of 450 ova l^− 1, and were detected in all septage sludge samples with an average of 16,000 ova l^− 1. Twelve varieties of helminth ova were identified. More helminth ova varieties in higher concentrations were found in septage than those reported from stool samples. The varieties' frequency ranged from 10% to 50% and Ascaris lumbricoides predominated. Results show that pathogens and indicator micro-organisms, especially helminth ova, accumulate in sludge. Thus helminth ova should be considered when septage sludge is treated and used for agriculture. Proper health protection measures must be applied for people handling septage.     

在市场中实践在实践中学习在学习中进步--工程公司市场化进程的回顾与展望

近两年来，工程公司在提高市场竞争意识、推动市场化进程中做了大量工作，其中坚持走出去的方针是我们自我加压、推行加快市场化步伐的一个重要战略步骤。     

新时期广东城市化的新特点

新时期广东城市化出现以下特点:知识源导向、城市由单体向群体化发展、产业集群推动、政府主导自上而下的集约化发展、城镇化向城市化转变、由重“数量”发展向重“质量”发展的转变。     

新形势下高校强化基建财务管理的探讨

在市场条件下高校基建财务人员在加强日常财务管理的同时,必须树立起高度的工作责任心,抓好事前监督、事中监督、事后监督三个环节,全面理解、贯彻执行《高等学校财务制度》,管好用好各项基本建设资金,提高基建财务管理水平,更好地完成高校各项基建任务,以有限的投资,最快的建设速度,获得最大的投资效益。     

2005年北京办公物业市场七大趋势

趋势一:CBD区域写字楼集中放量从各区域规划方案上看,CBD区域多数项目在03～04年处于项目的报批手续及拆阶段,预计2005年正式推向市场,因此2005年CBD区域将成为北京市场供应集中的域,区域即将供应的项目有北京财富中心(二期)、金地国际花园、万达广场、SOHO尚都、万通中心、世纪财富中心、怡禾国际中心、光华国际等。除去未知项目,2005CBD写字楼办公面积的供应量为60万平方米左右。中关村区域经过一段时间的集中供后开始逐步放缓,2005年供应的体量相对较大的项目有中关村金融中心、新中关。金街区域可能开盘的项目只有2个:英蓝国际中…     

浅谈我国工程项目建设成本控制存在的问题

结合目前我国施工企业工程项目成本管理现状,对工程项目成本管理过程中存在的问题进行了较详细的分析,并提出了一些解决问题的办法,以做好项目成本控制工作,进而增强企业经济实力。     

Variation in property taxation in Tulsa

Conclusions It may be reasonably concluded from this study that the range of variation in these ratios of assessed to actual value are of a reasonable size for the great majority of cases. The frequency distribution of these sample ratios was not normal, however, as was assumed a process of this type would produce. On the other hand, the failure of the regression analysis to identify any significant variables which would explain these variations would tend to re-enforce the assumption that the fluctuations were indeed of a random nature.To sum it up in one paragraph, aside from a few extreme cases, the assessing process appears to give estimates which are more consistent than would be expected under the assumption that any errors would be of a random nature, but the regression analysis was unable to isolate any particular socioeconomic characteristics which would explain the variation which was present.Financial support for this research project was furnished by the University of Tulsa.