共查询到20条相似文献,搜索用时 609 毫秒
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对电热法液体汽化热实验进行了研究,设计了新的实验装置.将盛液体的容器置于保温杯中,保温杯放置在电子天平上,液体由电加热器加热,液体蒸气由出气口排出,排出的液体蒸气的质量可由电子天平实时测量.装置改进后,测量更简单方便,结果更准确. 相似文献
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光纤法布里-珀罗(Fabry-Perot)腔液位传感器 总被引:21,自引:7,他引:14
提出了一种用于测量液体容器液位高度的新型光纤F-P(Fabry-Perot)腔传感器,它灵敏度高,实现了全光传感和传输,特别适用于一些有害、易燃、易爆液体容器液位的测定.详细分析了该类传感器的传感原理,并给出了传感头参量设计方法.实验结果表明,光纤F-P腔传感器测量液位方法简单,并且可达到相当高的精度.文中分析了实验中的误差,探讨了传感器的稳定性及改进方法,是光纤法布里-珀罗腔传感器实用化的有效尝试. 相似文献
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We present a method for measuring powder resistivity as a function of moisture using a one-step process. The developed new resistivity cell consists of narrow horizontal electrode surrounded by a grounded guard electrode and simultaneous measurement of humidity within the powder bed. The system was modeled using computer simulations. As an example, resistivities of three different lactoses, wheat flour and quartz are presented. Resistivity was found to decrease several orders of magnitude between 10 RH% and 90 RH%. Simulated results showed that if no guard plate is used, measurement errors caused by humidity gradient are of order of magnitude. 相似文献
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本文介绍了一种测量空气比热容比γ值的方法。重点分析了测量值的准确度与实验过程中打人气体多少的关系。为准确测量γ值提供了有力依据。 相似文献
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HU ZhiQiang YANG JianMin ZHAO YingNian & BAI Gang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai China China National Offshore Oil Corporations Limited Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(1)
A joint industry project on a full scale measurement of Fenjin FPSO,headed by Shanghai Jiao Tong University and sponsored by CNOOC,was initiated in October 2007 and has been going on for more than 25 months.The purpose of the project is to measure and collect the motions in six-degrees of freedom of an FPSO,and to collect the environmental loads at the offshore oil-field.A motion data measuring system is designed and installed on the FPSO.Another environmental data measuring system is installed on a fixed j... 相似文献
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本文借助金相显微镜, XRD, SEM和DSC等手段对Cu75.15Al24.85合金经1-5 GPa压力, 750℃保温15 min处理前后的组织结构进行了分析,并用电阻率测试仪对合金的 电阻率进行测试,以此探讨了高压处理对Cu75.15Al24.85合金组织与电阻率的影响. 结果表明:高压处理能细化Cu75.15Al24.85合金的组织,增大合金的电阻率, 当压力为3 GPa时,该合金获得的组织最细小,电阻率最大. 相似文献
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This article describes an experimental procedure conducted to estimate and investigate the transient thermal contact conductance (or thermal contact resistance) between the electrodes and workpieces during resistance spot welding. A fine thermal metrology was developed to collect thermal histories near the welding region. Indeed, the electrode tip was instrumented with several interior microthermocouples for measuring the transient temperature response during the welding process. A simple mathematical model, using an inverse heat transfer method, was built for the estimation of the transient heat transfer coefficient from interior transient temperature measurements. A simple resistance welding case of two steel sheets was investigated. The initial transient values of thermal contact conductance were found to be in agreement with those observed in the dry copper–steel solid contact case. At the end of the process, the transient heat transfer coefficient reaches a high value corresponding to the best heat transfer phenomenon at the interface during the welding process. When the metal is melted, the contact quality increases due to the high-applied electrode force. Higher electrode force and heating temperatures produce lower thermal contact resistance. The results obtained show the capabilities and the power of the coupled thermal metrology and transient inverse technique developed to investigate thermal history of resistance spot welding. 相似文献
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本文研究并设计了一种可以连续测量液体密度的实验装置。该装置通过微机自动采集数据,直接给出测量结果,可用于原油密度监测等 相似文献
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