制冷剂的替代对汽车空调的影响

主要讨论了R12及其替代物质R134a的性能对比,以及由于替代而给汽车空调系统带来的一系列变化。     

制冷剂替代对汽车空调系统的影响

主要讨论了R12与其替代物质R134a的性能对比,以及由于替代而给汽车空调系统带来的一系列变化。     

船用制冷装置制冷剂R12及其替代物的比较研究

由于制冷剂R12破坏臭氧层而受到禁用的日期愈来逾近，因此，在船用制冷装置中原来应用的R12必须由合适的制冷来替代。目前不少远洋船舶上已用R22替代R12，但是有些装置是不适合用R22的。本对R12及其几种主要替代物的对比及分析、研究作为今后替代R12时的参考。     

关于汽车空调制冷不足的探讨

1汽车空调制冷概述 汽车空调是利用R12或是R134a压缩释放的瞬间体积急剧膨胀就要吸收大量热能的原理制冷。压缩机往往是安装在发动机上,并用皮带驱动,冷凝器安装在汽车散热器的前方,而蒸发器在车里面,工作时从蒸发器出来的低压气态制冷剂流经压缩机变成高压高温气体,     

钠通道SCN5a突变体R104W的构建及验证

目的构建并验证Brugada综合征相关钠通道SCN5a基因R104W突变体。方法采用一步法PCR突变技术,以pEGFP-SCN5a为模板,体外定点诱变构建pEGFP-SCN5a-R104W突变体,进行基因测序,并用Lipofectamine TM3000脂质体转染法转入HEK293细胞,通过Western blotting和膜片钳记录检测蛋白质表达和电流加以验证。结果测序结果显示SCN5a-R104W突变体基因序列上第310C>T,其他序列碱基与野生型相比未发生改变;Western blotting结果显示SCN5a-R104W突变体蛋白表达量较野生型SCN5a降低;荧光显微镜下显示SCN5a-R104W突变体蛋白位于胞质内;SCN5a-R104W突变体转染后膜片钳记录未能检测到钠电流,且R104W突变体对野生型通道有负显性抑制作用。结论成功构建并验证SCN5a基因R104W突变体。     

深入分析关系R的性质

离散数学中的关系R是一个重要的基本概念。根据定义在一个集合A上的关系R的六个性质的英文定义,利用蕴含式的逻辑特点,从有序对和关系R的矩阵M_R两个角度对每个性质逐一进行分析,得出在判定关系R的性质时可用的结论,并且分析了自反性与非自反性之间、对称性与反对称性之间、对称性与非对称性之间、非自反性和反对称性以及非对称性之间的联系。     

深入分析关系R的性质

离散数学中的关系R是一个重要的基本概念.根据定义在一个集合A上的关系R的六个性质的英文定义,利用蕴含式的逻辑特点,从有序对和关系R的矩阵MR两个角度对每个性质逐一进行分析,得出在判定关系R的性质时可用的结论,并且分析了自反性与非自反性之间、对称性与反对称性之间、对称性与非对称性之间、非自反性和反对称性以及非对称性之间的联系.     

深圳市首个P＋R社会停车场开放

深圳市首个P＋R社会停车场正式对市民开放，该停车场是深圳市首个由政府投资兴建的P＋R停车场，位于最为拥堵的交通节点梅林关（入关方向右侧），毗邻地铁4号线民乐站出入口。停车场面积3．83万m^2，设置小汽车停车泊位1089个，目前停车场开通出入口各1个。车辆可沿梅林检查站进深圳市区方向最右侧车道、经地铁4号线民乐站口往前约100m处进入停车场，从出口拐入南坪快速路。     

ABT R8 5．2 FSI

无可否认，ABT是改装大厂，同时他们擅长带来超高马力的机器怪兽；面对着R8所匹配的的5.2L FSI缸内直喷V10发动机，391kW的最大输出功率，ABT Sportsline一点都不满足，在他们眼里，需要更强悍的表现。     

钢铁侠座驾难产2013奥迪R8e-tron Concept

日前据外媒报道，奥迪方面正式确认了R8e-tron电动超跑将不会公开售卖，至此．观望基本可以停止了，其已经按“量产标准”生产的10台R8e-tron电动跑车将保留作为测试使用。     

Experimental research and optimization on the environmental friendly R1234yf refrigerant in automobile air conditioning system

Currently, the refrigerant used in the automotive air conditioning system is R134a which has a high global warming potential (GWP) value, so people are eager to find a good replacement for it. According to recent studies, R1234yf is considered as one of the top candidates to replace R134a. In this article, the performances of R1234yf “drop-in” system and the optimization to the R1234yf system are experimentally studied and investigated. The expansion valve used for the R1234yf system is optimized by changing the charged fluid and adjusting the spring force. The results indicate that it can improve the performance of R1234yf system significantly through adjusting the thermostatic expansion valve. For the thermostatic expansion valves (TEVs) charged with R134a in thermal bulb, the system performance is optimal. Compared to the original expansion valve, for the R1234yf system applying the adjusted expansion valves, under different working conditions the cooling capacity increases by 11.3% averagely and the coefficient of performance (COP) increases by 8% averagely.     

R407C取代R22的工况计算及分析

围绕制冷剂发展历程和制冷剂技术更新进行了讨论.着重介绍制冷剂R407C替换制冷剂R22的工况计算,基于生产实践提出了制冷剂替换对系统的影响以及系统需要做出的改变.     

POLYNOMIAL CURVE FITTING METHOD FOR REFRIGERANT THERMODYNAMIC SATURATION PROPERTIES

Ｎｏｍｅｎｃｌａｔｕｒｅａ—ｅｍｐｉｒｉｃａｌｃｏｅｆｆｉｃｉｅｎｔｓｐ—ｐｒｅｓｓｕｒｅ，１００ｋＰａＴ—ｔｅｍｐｅｒａｔｕｒｅ，Ｋｅ—ｔｅｍｐｏｒａｒｙｖａｒｉａｂｌｅ，ｏｒｍａｘｉｍｕｍｒｅｌａｔｉｖｅｂｉａｓｈ—ｅｎｔｈａｌｐｙ，１０ｋＪ／ｋｇｉ—ｔｈｅｉｔｈｓｅｇｍｅｎｔｏｆｆｉｔｔｉｎｇｒａｎｇｅｓ—ｅｎｔｒｏｐｙ，ｋＪ／（ｋｇ·Ｋ）ｕ，ｖ—ｖａｒｉａｂｌｅｓｉｎＥｑ．（１）ｘ，ｙ—ｖａｒｉａｂｌｅｓｗｈｉｃｈｓｔａｎｄｆｏｒａｎｙｓａｔｕｒａｔｉｏｎｐｒｏｐｅｒｔｉｅｓｏｆｒｅｆｒ…     

DETERMINATIONSOFREFRIGERANTCHARGEOFAREFRIGERATORWHENREFRIGERANTISREPLACEDBYR134aORR152a

ＤＥＴＥＲＭＩＮＡＴＩＯＮＳＯＦＲＥＦＲＩＧＥＲＡＮＴＣＨＡＲＧＥＯＦＡＲＥＦＲＩＧＥＲＡＴＯＲＷＨＥＮＲＥＦＲＩＧＥＲＡＮＴＩＳＲＥＰＬＡＣＥＤＢＹＲ１３４ａＯＲＲ１５２ａ＊ＤｉｎｇＧｕｏｌｉａｎｇＷａｎｇＸｉａｎｆｅｎｇＺｈａｎｇＣｈｕｎｌｕＣｈ...     

Convective Boiling of Near-Azeotropic Refrigerant R410A in the Horizontal Micro-fin Tube

Using near-azeotropic refrigerant R410A as the working fluid, the experimental studies on the horizontal micro-fin tubes were conducted. Several factors affecting heat transfer coefficients were analyzed, and the characteristics of flow boiling of the refrigerant in the horizontal micro-fin tubes were discussed. The local heat transfer coefficients increase with mass flux, heat flux and quality. And the heat transfer enhancement factor of those testing tubes is about 1.6 to 2.2.     

汽车空调制冷剂回收机理及方法的实现

介绍了国家环保总局汽车空调CFC-12制冷剂回收培训项目的背景、意义,及广东交通职业技术学院在该项目中所做的工作。阐明了汽车空调CFC-12制冷剂回收的机理与方法,经实践证明,该回收方法具有良好的操作性及较大的推广价值。     

汽车空调维修制冷剂作业技术规范的研究

汽车空调制冷剂的释放与泄漏,其中的60％与汽车空调的维修有关,主要是人为释放和自然泄漏,它造成了对环境的污染。通过对汽车空调维修特点及制冷剂使用的分析,研究提出制冷剂回收、净化、加注、检验作业等技术规范．能够遏制制冷剂的释放与消耗,是汽车维修业保护臭氧层、减少温室气体排放的有效措施。     

Effect of Header Configuration on Refrigerant Distribution in Parallel Flow Microchannel Evaporators

The refrigerant flow distribution in the parallel flow microchannel evaporators is experimentally investigated to study the effect of header configuration.Six different configurations are tested in the same evaporator by installing insertion device and partition plate in the header to ensure the consistency of the other structure parameters.The results show that the uniformity of refrigerant flow distribution and the heat transfer rate are greatly improved by reducing the sectional area of header.The heat transfer rate can increase by 67.93% by reducing the sectional area of both inlet and outlet headers.The uniformity of refrigerant flow distribution and the heat transfer rate become worse after installing the partition plate in the insertion devices and changing the inner structure of the header further.