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蒸发冷却与冷却吊顶相结合的半集中式空调系统的探讨 总被引:11,自引:0,他引:11
提出了一种新的半集中式蒸发冷却空调系统方案,即将蒸发冷却技术与冷却吊顶相结合。蒸发冷却空调机组承担室内的新风潜热负荷;冷却吊顶承担室内显热负荷,而且冷却吊顶盘管中所需要的冷水采用新疆地区当地的天然地下水、自来水或冷却塔产生的冷却水(水温16~18℃)。冷却吊顶在夏季用作冷辐射(通16~18℃的冷水),冬季用作热辐射(通60℃左右的热水),从而使蒸发冷却空调系统达到节能,减少送风管道尺寸且满足全年运行的需要。 相似文献
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四、冷却曲线法在齿轮淬火冷却监控中的应用
1.齿轮淬火过程中淬火介质的监控
目前,用于齿轮淬火的介质主要是各种淬火油、水溶性淬火介质和普通自来水。
自来水是最经济而又清洁的淬火介质。一些含碳量低、淬透性差且形状简单的齿轮的调质淬火和感应加热淬火,往往可以采用自来水。但自来水的冷却能力随着水温的不同而有所不同,不同国家及不同地区的自来水的冷却能力也有差别,使用淬火介质冷却能力监测设备可以很好地储存此类信息,控制不同的水温,为不同大小及不同材质的齿轮工件淬火提供技术依据。 相似文献
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一、前言电子整机的功耗是以热能的形式散发出来的,这些热能使元器件及整机内部温度升高。随着高功率密度组装件在整机上的应用,电子设备散热问题日益突出。提高电子设备的热可靠性能,除了采用新型高效散热技术外,还必须对设备中的热进行热管理,使设备的元器件处于最佳的热状态。热管理技术不是局部的,而必须是全面的、有效的。实践证明,凡是进行了合理的热管理的设备都具有良好的热性能,并可产生明显的经济效益。 相似文献
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水表新国家标准中压力损失值与常用流量、流量测量范围的关系 总被引:2,自引:0,他引:2
干曼芝 《机械工业标准化与质量》2008,(7):34-35
水表新国家标准GB/T778.1~3—2007《封闭满管道中水流量的测量饮用冷水水表和热水水表》于2007年9月12日发布。自2008年5月1日起实施。水表新标准适用范围大大增宽。它反应了水计量管理、市场竞争的发展趋势。并充分体现了水表的技术进步。 相似文献
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陈俊杰 《仪器仪表与分析监测》1995,(4)
本文介绍并研究了由笔者设计并研制成功的实现压力峰值锁定功能的4 1/2位数字测力仪。由于在峰值锁定功能的实现上采用了数字化电路,因而锁定时间为无限长。而且该仪器在系统设计及制作装配工艺、地线系统及抗干扰技术等方面采取了诸多有效的措施,故此整机的精度及稳定度高,抗干扰能力强。并且该仪器又备有定值报警功能,用户可根据各自的要求自行设定报警点,整机的成本又低、体积小,因而具有较为广阔的市场前景。 相似文献
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A miniature surface plasmon resonance (SPR)–based immunoassay system for analyzing microcystin-LR (MC-LR) in surface water has been developed. A Spreeta biosensor was adopted in the SPR flow injection analysis (FIA) system. An optional biofilm immobilization method was exploited using covalent-coupling between a bioconjugate of microcystin-LR and bovine serum albumin [(MC-LR)-BSA] and the golden surface. An acceptable relative standard deviation of repeatability, 1.29% (n = 20), was achieved. An analysis of the calibration curve showed that this method has a detection limit of 0.55 ng/mL, a half-maximal inhibitory concentration (IC50) of 5.6 ng/mL, and a quantitative range of 1.56–25.00 ng/mL. The recovery from water samples containing varying concentrations of MC-LR ranged from 90% to 112%. After samples of tap water and pool water were assayed, it was concluded that tap water did not contain a measurable amount of the analyte, whereas pool water contained 2.39 ng/mL. Compared to other methods of analysis, SPR immunoassay has the advantage of being label-free, rapid, and cost-effective and can easily detect levels of MC-LR within the World Health Organization (WHO) drinking water guidelines. The SPR FIA system with reusable biosensor is compact and convenient for instant in situ determination of MC-LR levels in environmental water. 相似文献
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依据GB/T5750.7-2006《生活饮用水标准检验方法有机物综合指标》。生活饮用水中耗氧量的测定方法,分析和评定影响饮用水耗氧量含量的不确定度分量,建立数学模型,进而得到测量结果的不确定度。测量不确定度定义为表征合理地赋予被测量之值的分散性[1]。在ISO/IEC17025-1999中要求检测实验室具有评价不确定度的程序,能够对测量项目的不确定度做出正确的评估,满足客户及监测工作的要求。测量不确定度在实验室数据比对,方法确认、标准设备校准、量值溯源及实验室质量控制与管理方面具有重要的意义[2]。 相似文献
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针对直饮水机普遍存在的饮用水水质安全隐患、不易管理等问题,提出了一种基于GSM和Internet的直饮水机远程网络化控制平台的设计方案.分别设计了上位机模块、通信模块和下位机模块,设计了一种网站形式的信息交互平台,实现了可视化和人性化的操作与信息反馈;充分发挥了GSM和Internet网络两种通信手段的优势,通过采用短消息与网络通信相结合的信息传输方式,实现了信息的远程传递;根据双频电导率测定法原理,设计了一种基于CS5460A测量芯片的可集成饮用水水质检测模块,结合下位机各子模块的设计,实现了对直饮水机的水质监测与自动控制功能.研究结果表明,直饮水机远程网络化控制平台可方便地实现对直饮水机的水质监测、预警、实时维护、信息管理和远程控制等功能,确保直饮水机的饮用水水质安全. 相似文献
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The reduction of water consumption and the technical developments of the last decades, such as the use of tap aerators, water-saving appliances or the use of electronic measuring principles for water consumption measurements at household level, lead to increased and novel demands on flow metering technology. Nowadays, the meters used must be able to detect less water volume with a constant meter size and constantly changing flows. This makes it necessary.to check whether the demanded measurement accuracy is maintained under these changed boundary conditions. Against this background, the question arises to what extent the existing test regimes to assess the measuring performance of water meters are still appropriate. In order to answer this question, it is necessary to set up a metrological infrastructure that will enable water meters to be tested close to real-world operation conditions. Therefore, the following paper focusses on flow dynamics within the water consumption at the household level. One key factor to realize a representative test regime are reliable and representative water consumption measurements at household level. Within the “Metrology for real-world domestic water metering” project (MetroWaMet) within the European Metrology Programme for Innovation and Research (EMPIR) water consumption measurements were carried out in different European countries. Based on the water consumption measurements discussed essential consumption characteristics can be derived in terms of amplitudes and amplitude distributions, gradients or durations. One important outcome of the study is that water consumption in the four different European countries is comparable. This means based on the available consumption data a generally applicable test regime can be derived which can be extended if necessary. The guide developed regarding the planning and carrying out of consumption measurements can be used to collect further reliable and representative consumption data. 相似文献
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浸没式粉末硅藻土预涂覆微滤装置是一种新型自来水深度处理技术设备,利用粉末硅藻土形成滤膜实现表面精细过滤,提高过滤效果,可用于新建自来水厂深度处理及已建自来水厂的达标改造。本文阐述了浸没式粉末硅藻土预涂覆微滤装置的技术原理、装置结构及试验系统组成、试验流程。通过试验,本文得出浸没式粉末硅藻土预涂覆微滤装置的运行周期、对浊度、细菌、CODMn、藻类等水中杂物的处理效果。本文也探索了滤膜厚度,粉末硅藻土在线投加量过滤阻力值等过滤工艺参数,对大型市政自来水厂采用浸没式粉末硅藻土预涂覆微滤技术设计及应用有一定参考作用。 相似文献
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针对日常生活中因突然停水而忘记关闭水龙头造成自来水浪费的现象,设计了一种机械式停水自闭水龙头,能解决因停水后忘记关水龙头的问题,从而节约水资源. 相似文献