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由于高能激光能量计标定过程中没有标准的能量测量装置和标准的激光源,无法采用常规方法对其进行标校。提出了一种利用现有小能量计从低到高逐级多次传递不确定度的方法,以及一种利用能量等效原理对激光能量计进行标校的方法。不确定度传递法方法简单,但环节较多导致不确定度较大。等效标定法包括电标法和光标法,电标法对设计要求较高,但求解过程相对简单。光标法工程实现难度要低得多,但必须事先对灯组余热及热损失进行测算。等效法的三个条件与误差大小关系紧密,在结构设计中必须严格考虑,它是提高测量准确性的根本,其次要尽量减少不确定度传递的中间环节,最后需要对误差项进行科学分析和测定,在此基础上对这些项进行相应的修正和补偿。 相似文献
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LI Qiang ZHU Yuying HE Yunha WANG Xu LI Gong YU Jinku & SU Zhibin .Key Laboratory of Metastable Materials Science &Technology Yanshan University QinhuangdaO China .Department of Mechanical Engineering Yanshan University Qinhuangdao China .Department of Environmental & Chemical Engineering Yanshan University QinhuangdaO . China 《中国科学G辑(英文版)》2004,47(5):581-587
~~Undercooling and solidification of germanium melts studied by differential scanning calorimeter~~ 相似文献
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This paper presents several applications of the PHI-TEC II that are not commonly associated with adiabatic calorimeters but which have proved to be extremely valuable. These include simulation of a deep oil well for enhanced oil recovery, isothermal calorimetry of a semibatch reaction, catalyst research using flow through reactors (both plug flow and CSTR) with controlled feeds of high pressure liquid and gas.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
25.
Novel flame retardants containing cyclodextrin nanosponges and phosphorus compounds to enhance EVA combustion properties 总被引:1,自引:0,他引:1
Jenny Alongi Merima Poškovi? Francesco Trotta 《Polymer Degradation and Stability》2010,95(10):2093-2100
A novel flame retardant intumescent system, aimed to improve the fire stability of ethylene vinyl acetate copolymer (EVA), has been prepared by melt blending of the copolymer and a complex of cyclodextrin nanosponge-phosphorus compounds. As compared to traditional systems, this complex, stable in processing conditions, has the advantage that nanosponges act as both carbon sources and foam forming agents while the phosphorus compounds are able to directly generate phosphoric acid in situ. In this context, cyclodextrin nanosponges undergo dehydration in presence of the acid source, generating water vapour and char, and thus protecting the copolymer against combustion. Different acid sources have been investigated in order to reach the optimum interaction with the nanosponges. Raman measurements and thermogravimetric analyses have shown that the cavities of nanosponges entrapped the phosphorus derivatives forming stable complexes at the temperature of EVA processing. Different amounts of these complexes (5, 10 and 15 wt.%) have been added to EVA via melt blending and their flame retardancy properties measured by UL94 test and cone calorimetry. Strongly modified burning kinetics, as compared to the behaviour of the neat copolymer, have been found by UL94 test: V2 classification has been achieved for every formulation regardless of the type and the amount of complex used. EVA combustion behaviour by cone calorimetry has also been significantly affected: the heat release rate decreased dramatically down to ca. 20% in the presence of these new additives. 相似文献
26.
Thermal characteristics and rheological behaviour of eight crude oils covered a wide range of fluid composition and properties
were studied by differential scanning calorimeter (DSC) and viscometry. Wax appearance temperatures (WAT) of crude oils were
determined by DSC and viscometry. Good agreement is obtained between the results. The dynamic viscosity in the Newtonian temperature
range of the crude oils (above 30°C) generally obeyed a simple first-order Arrhenius type of temperature dependence. Activation
energies of flow in the non-Newtonian range are not uniquely defined.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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精密滴定热量计的研制 总被引:2,自引:0,他引:2
介绍一种精密滴定热量计,阐述热量计的设计原理,并对其结构进行了详细的阐述。热量计有效反应体积为100mL,恒温槽控温精度为±0.001 K,测温灵敏度为5×10~(-5)K,加样精度为0.5μL。用THAM对仪器进行了标定,测得溶解热为—47567±76J·mol~(-1),与文献值吻合。 相似文献
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