深圳市天然气基准气类别的选择

考虑深圳市目前及潜在天然气气源的多样性、燃气互换性、天然气类别及燃具适应性,对深圳市天然气基准气的选择进行了探讨.深圳市使用的天然气应符合GB 17820-1999<天然气>中一、二类天然气的技术指标,以及GB/T 19207-2003<液化天然气的一般特性>中甲烷体积分数的要求,对照GB/T 13611-2006<城市燃气分类和基本特性>确定基准气类别.深圳市目前使用的天然气(澳洲LNG、新疆LNG)符合12T范围,考虑潜在天然气气源,深圳市天然气的基准气类别宜选择12T.     

燃气组分改变对燃具的影响

燃气组分改变对燃具的影响陈允席庆梅王强（合肥市煤气总公司，合肥２３０００１）关键词燃烧器具燃烧器适应性燃气互换性中图分类号ＴＵ９９６．７５１问题的提出合肥市煤气总公司三期工程投产以前，制气能力只有１０００００／ｄ焦炉气，仅能够满足６万户居民用气及少...     

民用燃具的运行特性

燃气成分的变化将引起燃气燃烧特性的改变,燃具热负荷、一次空气系数、火焰结构及燃烧稳定性发生变化。分析了当燃气成分发生变化时,配有大气式燃烧器的民用燃具在不加任何调整的情况下,其运行工况的变化规律,这对燃气互换性和燃具适应性的研究以及燃具的设计均有实际意义。     

汽化气作为燃气补充气源的可行性初探

针对阳泉市矿井气将会出现供不应求的现象,从互换性、安全性和经济性三方面对液化气作为补充气源的可行性进行分析,指出液化气与矿井气不具有互换性,对人身也有极大危害,故不宜作为补充气源。     

研制高适应性燃具的必要性

简述了燃气互换性与燃具适应性的关系,分析了我国天然气互换性与燃具适应性的现状及存在的问题,总结了国外的相关经验,讨论了研发高适应性燃具的必要性和可能性,提出了实施的建议。     

液化气混空气燃气与天然气的互换性

燃气互换性问题存在于城市燃气供应的始终，在供气气源的性质发生较大变化时问题尤为突出。在液化气混空气为主要气源的城市燃气供气系统中，将来引进天然气时，所遇到的问题中最重要的就是液化气混空气燃气与天然气之间的互换性问题。作者采用美国燃气协会(A．G．A．)互换性判定方法，对这两种燃气的互换性进行了判定分析，并根据燃气用具的运行特性，分析了以液化气混空气燃气作为基准气设计和进行初调整的燃气用具，使用天然气后可能出现的问题。为将来天然气能顺利地与液化气混空气置换提出了合适的液化气混空气比例。     

燃气组分改变对燃烧器具燃烧特性的影响

分析与研究了燃气的互换性,燃气转换后对燃具燃烧特性的影响,探讨了燃气置换的措施和方法。     

第一族燃气互换性的研究

一、前言 第一族燃气互换性的研究在欧洲已基本结束,现在它们的城市燃气主要是天然气。但我国天然气产量不高,人工燃气在相当长一段时间内将会是城市燃气的主要气源。因此,研究第一族燃气的互换性问题,在我国是有现实意义的。 法国是研究燃气互换性较早,也较成功的国家之一。法国规定:为保证燃具正常工     

韦弗法燃气互换性公式和图表的评述(一)

自从《美国燃气协会燃气互换性公式评述》一文在本刊2012年分4期刊出后,笔者就感到应对燃气互换性的韦弗法也做一个分析和评述。两种方法互换性指数的表达公式不同。韦弗法采用了6个互换指数,调定气也多了3种。36号公告法对不同调定气有不同的制定要求,而韦弗法则采用统一的制定要求。韦弗法采用的6个互换性指数的概念十分明确,两个是燃具设计的基本要求(热入力与效率因素),两个与火焰速度有关(离焰与回火),两个与火焰速度基本无关的指数(黄焰端与不完全燃烧)则有所创新。美国的评论认为韦弗法对互换性问题感兴趣的人都应该阅读的论文。     

LPG改质气掺混LPG用于天然气燃具的试验

介绍了用LPG改质气掺混LPG配制不同试验气进行燃具试验的要求和方法,分析了试验结果。以12T基准气华白数配气得到的掺混气可以替代天然气作为补充气源或应急气源。     

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。     

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…     

Developments in immersed tunnelling in Holland

Holland has 22 immersed tunnels (14 road, 5 rail and 3 utilities tunnels). Another three are under construction, and more are foreseen. The tunnels are of the concrete type, i.e., constructed without a steel shell. The paper describes developments in technology and in design philosophy since the first immersed tunnel was completed 52 years ago. These developments include, amongst others: the introduction of the Gina rubber gasket between elements; the division of elements into sections divided by flexible joints; the application (if possible) of longer elements (up to 268 m); the use of precast sections for tunnels that have a small cross-section; the omission of the watertight lining (made possible by cooling the concrete of the walls during the first days after pouring); various foundation methods (e.g., sand flow instead of sand jet system; piled foundations when necessary); the use of the excavation for the open ramps (or the part of the tunnel built on land) as a casting basin for the elements; the changed approach to casting basins now that well pumping is usually forbidden; and the transport of the elements across shallow locations and across the sea. It is emphasized that the current state of immersed tunnel technology is the result of a continuous international exchange of ideas and experiences.     

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。