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1.
鹏飞 《太阳能》2008,(5):6-8
随着中国经济的飞速发展,能源短缺,环境污染等问题日益严重.欧美等发达国家早已开始着手解决这些问题,每年都有大量来自于政府、企业和风险投资的资金用于清洁技术的研究与应用.根据道琼斯数据显示,2007年在清洁技术领域,全球共发生了221项投资案例,投资总额达30亿美元,比2006年增长了43%.  相似文献   

2.
第十七届世界国际氢能大会于2008年6月15日~19日在澳大利亚布里斯班市举行,来自全世界44个国家的600余位代表聚集一堂,讨论当代氧能技术和发展趋势.  相似文献   

3.
The adiabatic film effectivenessηof the counter-inclined film-holes fed by varying internal coolant intake on the turbine vane leading edge model was experimentally investigated.A semi-cylinder model was adopted to model the vane leading edge which was arranged with two-row holes,which located at±15°on both sides.The four Leading edge model with the combinations of hole-shape(simple holes and laid-back holes)and intake structure(plenum and impingement)were tested under four blowing ratios M of 0.5,1.0,1.5,and 2.0.Theηcontours were obtained by the transient measurement technique based on double thermochromic liquid-crystals.The results present that theηis sensitive to the M for the four studied leading edge cases.The addition of impingement enhances theηfor the two studied holes.The film jets make the coolant-flow closed to the target surface,resulting in higherηunder lower M.The core with higherηappears in the downstream area of hole-exit.Theηenhancement can be provided to almost the identical level by adding the impingement-holes and improving the hole-exit shaping in most areas.With increasing M,the jets with stronger exit normal momentum penetrate into the main-flow.The impingement addition may be a more effective program to upgrade theηrelatively to the exit shaping under larger M.Besides,the laid-back holes with impingement case produce the highest film cooling performance among the four cases,providing great potential in the leading edge especially under larger M.  相似文献   

4.
经国务院批准,国家发展改革委、财政部、国家电监会近日联合下发了《关于进一步贯彻落实差别电价政策有关问题的通知》(以下简称《通知》),要求各地限期全面落实差别电价政策.  相似文献   

5.
热泵辅助太阳能中央热水系统年运行特性研究   总被引:3,自引:0,他引:3  
提出采用热泵来取代传统的电加热器,构成热泵辅助太阳能中央热水系统,可有效地降低能源消耗.结合2005年西安地区气象数据,建立了合适的数学模型,并用现有的试验数据对模型进行了校准,通过模型模拟了该年热泵辅助和电辅助太阳能中央热水系统的性能系数,输入功耗,出水温度等运行参数,并对两者进行了对比.  相似文献   

6.
一、太阳与太阳能 众所周知,在浩翰的宇宙中有一颗离我们最近的恒星--太阳.现代科学表明太阳距离我们相当遥远,达到1.5亿km,虽然太阳光的传播速度为30万km/s,但我们在地球上所见到的光线已经是8min之前从太阳发出的光线了.太阳的直径为139万km,而地球直径仅为1.27万km,太阳的直径约为地球直径的109倍,其体积则比地球大130多万倍.尽管如此,由于距离遥远,太阳张角仅仅为32′.  相似文献   

7.
Under the back-side windy condition,the convection and radiation heat transfer characteristics in an iso-flux upward-facing cylindrical cavity were studied by three-dimensional numerical simulation.The impacts of cavity tilt angle,wind incident angle and wind speed on convection and radiation heat transfer Nusselt number Nuc and Nur were analyzed,and the possible explanations for their impacts were presented.Results show that due to the disturbance of wind,the influence of cavity tilt angle becomes more complicated and is related to wind incident angle and wind speed.The variation of Nuc or Nur with wind incident angle is different for different cavity tilt angles.Despite of the changes of cavity tilt angle or wind incident angle,the Nuc increases with the wind speed while the Nur presents a declination with the increasing of wind speed.Hence,compared with cavity tilt angle and wind incident angle,wind speed may be the dominant factor affecting or controlling the convective and radiation heat transfer of cavity.  相似文献   

8.
担当     
<正>6月30日,当中国政府将《强化应对气候变化行动——中国国家自主贡献》提交给联合国气候变化框架公约秘书处后,全世界都为中国的决定而侧目。中国设定了一个宏大的减排目标,振奋了各国应对气候变暖的神经。潘基文在声明中称赞中国提出的方案为在巴黎气候变化大会上增加动力、增强互信起到了积极推动作用;联合国秘书长副发言人哈克表示,中国提交自主贡献文件,为巴黎气候大会达成新的气候变化协议注入了动力,  相似文献   

9.
一物料干燥的能耗与环境污染 干燥作业涉及国民经济的广泛领域,是许多行业不可缺少的工序.在粮食、食品、果品、药材、木材、皮革、橡胶和陶瓷等许多产品的加工处理过程中,干燥作业对产品的质量和成本影响很大.  相似文献   

10.
户用小型风力发电系统现状与发展(上)   总被引:6,自引:0,他引:6  
<中华人民共和国可再生能源法>已于2005年2月28日在全国人大第11届第14次会议上通过,并将于2006年1月1日起施行,该法的颁布和实施,给小型风力发电行业的发展带来希望和光明,也必将大大促进农村能源的发展,户用风力发电产业也将会更上一层楼,前景看好.  相似文献   

11.
本文以某发电厂的水力除渣系统为研究对象,介绍了ControlNet现场总线的特点和体系结构,论述了ControlNet现场总线与PLC结合组成的集散型控制系统的原理、设计原则和方法。  相似文献   

12.
The comparative metastatics of the theory of the mine in discrete time is performed in this paper conditionally upon a fixed horizon on four cases: the price of the extracted resource is a fixed parameter or it is time-dependent; the cost function depends on cumulative extraction or it does not. Though some of these results are qualitatively (sign) well-known, it is the first time that these have been rigorously (quantitatively) derived in discrete time. The paper also shows that, even though the (sufficient) conditions of Samuelson's conjugate pairs theorem are almost never satisfied in the theory of the mine, the qualitative content of the metastatic results is very substantial indeed.  相似文献   

13.
《Energy Policy》2005,33(17):2272-2290
This paper contests the view held by the current UK government and its industry regulator, OFGEM, that liberalisation is good for security of supply. Focusing on the downstream aspects of the security of UK gas supply, on system security, it considers the impact of the different aspects of liberalisation: of legal governance, supply competition, de-integration, market simulation, regulation and the interaction of liberalised gas and electricity markets. Categorising these impacts in terms of security threats and threats to security response, it finds that individually and as a complex collectivity they have increased the risks of supply failure, either potential or already realised, in a variety of ways: from creating increased uncertainty and failing to signal adequate or appropriate investment, to legal ambiguity which divorces responsibility from liability and renders legal liability indeterminate ex ante. Moreover, one of the UK government’s responses to these increased dangers, which it does appear to perceive, is revealed as itself paralysed by the liberalisation paradigm: the government can only intervene pre-emptively with information in attempt to persuade the market to behave as it thinks it should. Meanwhile, however, the government has also had to recognise its default responsibility for security of supply and make preparations to intervene in an emergency situation: liberalisation can only be challenged when it is already too late.  相似文献   

14.
半导体热电堆发电的发展及展望   总被引:2,自引:0,他引:2  
热电发电是一种合理地利用地热、太阳能、海洋能及余热和废热等低势能转换为电能的有效方式。热电发电具有结构简单 ,无噪音、无震动、无磨损 ,运行寿命长 ,组合方便 ,实用面广 ,对热源温度要求低等特点 ,目前在国外已有使用 ,而在国内未见有关研究报道。可以相信随着热电材料的不断发展 ,以及制备工艺的不断完善 ,热电发电的前景会越来越光明。  相似文献   

15.
金属尾矿的堆弃是自然环境的一大公害,如果能所废弃的金属尾矿变成商品生产的一种原料,将是十分理想的,对含FeS2较高的金属尾矿做了多方面的实验研究,分析其应用于水泥原料中产生的各种效益,结果得出其能产生明显的节能效果,此外还可降低成本,保护环境。  相似文献   

16.
《Applied Thermal Engineering》2003,23(12):1525-1536
The purpose of this article is to present a method for identifying the apparent thermal effusivity of a wet soil. This thermal magnitude is indeed fundamentally important, as it fully characterises the behaviour of the system provided it is possible to make the assumption of a semi-infinite medium. The condition is very frequently encountered while studying heat transfers in soils. The apparent thermal effusivity of a soil is also particularly sensitive to the water content of the material. Because of this property, it is possible to evaluate the instantaneous water content of the medium from a correlation law linking thermal effusivity with water content.  相似文献   

17.
罗莹 《江西能源》1998,(4):32-35
本文论述了国内外建筑节能的发展及现状,重点针对目前我国南方建筑普遍存在的忽视建筑节能,阐述了南方建筑节能的必要性和迫切性,提出必须从设计开始,将建筑节能作为一项重要的内容加以考虑。并对建筑节能的有效途径进行了探讨。  相似文献   

18.
张华俊  陈浩  王俊  蒲亮  李洪峻 《节能》2001,(10):4-7
热电发电是一种合理地利用地热、太阳能、海洋能及余热和废热等低势能 转换为电能的有效方式。热电发电具有结构简单,无噪音、无震动、无磨损,运行 寿命长,组合方便,实用面广,对热源温度要求低等特点,目前在国外已有使用, 而在国内未见有关研究报道.可以相信随着热电材料的不断发展,以及制备工艺 的不断完善,热电发电的前景会越来越光明.  相似文献   

19.
柴油机外部冷却系统用于冷却柴油机的冷却液,其设计参数需满足柴油机最大运用功率长期运行的要求。在首台新造柴油机组装配完成后,需检测冷却参数并使其满足要求。在系统管路中加装孔板,改变冷却液流量是控制冷却参数的简单有效方法。  相似文献   

20.
润滑油精制后的废渣油调和制备燃料油的研究   总被引:3,自引:0,他引:3  
酸渣油作为润滑油酸精制工艺后的一种“废弃物”,通过与中温煤焦油和重油以一定比例的调和配制,附以少量添加剂的脱硫降粘除酸作用,可以调配成一种适合于国家燃料标准的燃料油,从而在克服传统处理方法——填埋处理造成环境污染的同时,产生可观的经济效益。  相似文献   

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