A New Mercury Gas-Controlled Heat Pipe for Temperature Amplifier and as Calibration Facility

At the Italian National Research Institute of Metrology, the activities and studies concerning gas-controlled heat pipes are constantly increasing in terms of involved personnel, instrumentation, and devices available. In the last two years, among the other activities, a totally new gas-controlled heat pipe operating with mercury as the working fluid has been designed, manufactured, and completely characterized. This heat pipe is made of stainless steel and provided with three thermometer wells. A dedicated furnace has been constructed and specific software algorithms have been implemented for the temperature and pressure control. This device will be used as a low-temperature reference for the new “Temperature Amplifier” and as a calibration facility for thermometers calibrated by comparison between 220°C and 450°C. All details regarding this heat pipe, including the assembly, filling, and testing procedures, and the complete characterization campaign are summarized here. Results in terms of temperature stability, uniformity, and time response are reported, and demonstrate the capabilities of this gas-controlled heat pipe to be a useful device for research and applications in contact thermometry. Another gas-controlled heat pipe operating with mercury and provided with six thermometer wells has been manufactured, and will be characterized for the contact thermometry calibration laboratory at INRiM and for other calibration companies in Italy; this device is also presented.     

Capabilities of a New Pressure Controller for Gas-Controlled Heat Pipes

Pressure control is used in many metrological applications and for the control of thermodynamic quantities. At the Italian National Research Institute of Metrology (INRiM), a new pressure controller has been designed and assembled, operating in the pressure range between 4 kPa and 400 kPa. This innovative instrument uses a commercial pressure transducer with a sensitivity of 10⁻⁴ and several electro-valves interposed among calibrated volumes of different dimensions in order to realize known ratios for very fine pressure changes. The device is provided with several circuits to drive the electro-valve actions, for signal processing and transmission, and for both manual and automatic control. Input/output peripherals, such as a 4 × 20 dot matrix display and a 4 × 4 keyboard, allow setting of the parameters and data visualization, while a remote control port allows interfacing with a computer. The operating principle of this pressure controller has been recently applied, with excellent results, to control the pressure in gas-controlled heat pipes by using a standard platinum resistance thermometer as a temperature/pressure sensor, achieving in this case a relative sensitivity better than 10⁻⁶ in pressure. Several tests were also made to control the pressure by means of a commercial sensor. The device, its main components, and its capabilities are here reported, together with application tests and results.     

辐射测温学研究进展

系统介绍了近年来辐射测淡不巫基础研究到应用研究的４个研究方向：热力学温度绝对测量，１ＴＳ－９０国际温标复现与比对，辐射法真温测量和应用技术研究，并针对辐射测温学的前沿课题提出了适宜于我国的研究方向。     

高精密自动绝热量热计

介绍了中国计量科学研究院用新近开发的高精密自动绝热量热计的测量控制系统对美国国家标准技术研究院（NIST）的标准物质α-Al2O3进行的比热测量,并对测量结果和不确定度作了分析。该自动绝热量热计是中国计量科学研究院原有的绝热量热计的发展,它继承了原有量热计的本体,又开发了高精度量热和温度自动测量控制系统。进行了与NIST的数据和其它数据对比以及不确定度分析。测量结果与NIST的数据相比,其相对均方根偏差为0．447％,一致性为0．167％。合成相对标准不确定度为0．333％。结果表明,该自动绝热量热计具有高精密量热和比热测量的能力。     

气体微流量测量技术的发展

本文介绍了美国NIST、德国PTB、日本NMIJ、意大利IMGC、韩国KRISS、中国计量科学研究院NIM和国防科技工业真空一级计量站(兰州物理研究所LIP)的气体微流量测量技术的研究进展,并对其测量方法,测量装置性能指标进行了评述。     

Construction of Sodium Heat-Pipe Furnaces and the Isothermal Characteristics of the Furnaces

Due to an excellent temperature flattening ability, annular sodium heat pipes operating from 500 °C to 1200 °C have been widely used as liners for isothermal furnaces to provide uniform and stable temperature zones. In order to develop the capabilities to fabricate liquid-metal heat pipes, an apparatus for fabricating sodium heat pipes was set up at the National Institute of Metrology (NIM), China. In this paper, the newly developed fabrication apparatus, the detailed procedures for manufacturing sodium heat pipes, the sodium heat pipes, the constructed furnaces for realizing the aluminum freezing point, and their isothermal characteristics are described. The experimental results showed that the biggest temperature differences within 150 mm from the bottom of the thermometer well in an aluminum point cell placed in the sodium heat-pipe furnaces were better than 15 mK, when the temperatures of the furnaces were controlled at approximately 657 °C.     

苯甲酸标准物质制备中区域熔融提纯装置的研制

阐述了中国计量科学研究院设计并研制的基于区域熔融原理的提纯装置,该装置用于制备一级热量标准物质苯甲酸。为了提高纯度,增加提纯后的产出量和效率,创新性地采用双加热炉进行同步加热,设计了角度调节器防止样品管的炸裂。提纯后的苯甲酸样品采用国家基准试剂纯度测定基准装置进行测定,测量结果为99.999%,扩展不确定度为 0.016%(k=2),从而验证了该装置满足标准物质的提纯要求。     

静压技术在液压式测力机上的应用

初步探讨了静压技术在液压式测力机上的应用,并介绍了中国计量科学研究院测力室的主要任务和工作。     

中俄激光功率量值比对

中国计量科学研究院和俄罗斯光学物理计量研究所于１９９２年实现了激光功率量值比对，比对使用ＮＩＭ激光功率副基准器，在ＶＮＩＯＦＩ激光功率副基准装置上进行，比对结果表明，两国激光功率量值的一致性优于０．１％。     

硅片表面超薄氧化硅层厚度测量关键比对CCQM-K32

利用X射线光电子能谱技术,建立了硅片表面超薄氧化硅层厚度（小于10 nm）准确测量方法。中国计量科学研究院参加了国际关键比对CCQM-K32,根据公布的国际关键比对结果,中国计量科学研究院的测量结果与参比的各国国家计量研究院的测量结果达到了等效一致,测量结果的不确定度为4.6%～7.0%。     

冷凝氡源的α能谱特性与活度计算方法研究

基于中国计量科学研究院建立的小立体角氡绝对测量装置,研究了冷凝氡源的α能谱随冷凝室内真空压力和冷指温度的变化特性,介绍了在少量杂质气体不可避免地被引入冷凝室、导致氡源能谱分辨率变化的情况下,如何计算冷凝氡源活度的方法.实验结果表明:氡源冷凝之后,杂质气体随时间逐渐增加会导致能谱分辨力变差,根据氡与子体衰变特性所建立的计算方法计算氡活度,得到连续5h的重复测量结果的一致性在0.45％以内,这对氡源活度的国际比对及量值传递具有重要意义.     

Thermal Characteristics of a Sealed Glass-Water Heat Pipe from 0?��C to 60?��C

Investigations into the thermal characteristics of glass-water heat pipes from 0 °C to 60 °C were carried out at the National Institute of Metrology (NIM), China. In this paper, studies on a glass-water heat pipe with four thermometer wells are described. The experimental results indicated that the temperature stability and uniformity of the thermometer well of the glass-water heat pipes are within several tenths of a millikelvin when the heat pipes are immersed in a constant-temperature liquid bath, since they have a highly effective thermal conductivity. They are able to maintain a constant temperature by the absorption or liberation of the latent heat of evaporation to attenuate temperature fluctuations of the surroundings. Also, above 0 °C to 30 °C, the temperature stability of the thermometer well of the glass-water heat pipe is better than 0.1 mK for approximately 16 h. The maximum temperature differences among the thermometer wells are less than 5.5 mK when the water heat pipes operate in the range from 0 °C to 60 °C. Therefore, water heat pipes are very promising to improve the performance of liquid baths and to accurately calibrate thermometers by comparison.     

高精度钠热管固定点炉及其等温特性

介绍了中国计量科学研究院新研制的两台高精度钠热管固定点炉(SHPF-1、SHPF-2),并测量了其垂直温场.当这两台钠热管固定点炉的炉温分别控制在比铝凝固点低约2℃、3℃时,铝点容器温度计阱底部150 mm范围内温场均匀性分别为15 mK和11 mK,并与国外同类的钠热管固定点炉的技术指标进行比较.此外,分析了影响固定点炉等温性能的因素.     

采用电补偿方案的新一代立式计算电容装置

针对立式计算电容最大不确定度来源的端部效应误差,中国计量科学研究院经过多年改进,研制出的最优中空电补偿电极在计算电容模型装置上,没有采用加装钉子头进行补偿的电补偿方案,并完成了诸如端部效应误差的补偿效果、偏心效应误差等电气性能验证试验,成功应用在新一代立式计算电容装置上。实验结果表明,采用电补偿方案的新一代立式计算电容装置复现1 pF电容单位的相对标准不确定度为1.0×10^-8。     

NIM和VNIIOFI光谱辐射照度双边比对

2014年12月至2015年1月,中国计量科学研究院(NIM)采用新研制的光谱辐射照度国家基准装置,与全俄光物理测量研究院(VNIIOFI)进行了光谱辐射照度双边比对。比对的波长范围为250～2500nm, NIM和VNIIOFI的光谱辐射照度测量均基于高温黑体辐射源BB3500M,采用高温计测量黑体的温度,溯源至Pt-C和Re-C固定点黑体,并采用WC-C固定点黑体进行了验证,双方在3021K的温度一致性优于70mK。光谱辐射照度双边比对结果表明: 44个比对波长点的光谱辐射照度的平均相对偏差为0.45%。除2000nm波长点的相对偏差为1.1%外,在全波段范围内量值的一致性优于0.90%,均在声称的不确定度范围内。     

细胞定量国际比对CCQM-P102及流式细胞技术的不确定度评定

对中国计量科学研究院应邀参加2010年CCQM-P102“具有特定表型的细胞定量测量比对”的测量过程、数据分析及不确定度评定进行了阐述。比对结果表明,中国计量科学研究院CD4+细胞计数测量结果与各参加国达到等效一致,成绩良好;其测量细胞平均CD4抗原值的细胞荧光强度值在经过对数转换及线性回归后,计算结果在国际比对不确定度范围内,并作为该比对提交测量不确定度的3个国家之一。对流式细胞术的测量不确定度评定进行了探讨。     

1mN·m～1N·m扭矩标准装置力臂系统

介绍了新研制的1 mN·m~1 N·m扭矩标准装置的关键部件——力臂系统的设计方案,并对力臂进行了不确定度分析。分析表明:1 N·m扭矩标准机力臂长度的不确定度为4.2×10~(-6)(k=2),完全满足1 N·m扭矩标准机技术指标的要求。     

用阵列测量技术对微米、亚微米单分散微球粒径定值

分析了微球阵列测量法的特征和应用情况,并采用该法对5种微米、亚微米单分散二氧化硅微球粒度标准物质进行了测量.其平均粒径可溯源到中国计量科学研究院标准长度.经与溯源至美国国家标准技术研究院标准长度的测量结果相对照,两个测量结果一致.证明微球阵列测量法可以应用到亚微米级单分散微球粒度标准物质的定值.     

Bilateral Comparison of Spectral Irradiance Between NIM and VNIIOFI from 250 to 2500 nm

With the new spectral irradiance measurement facility based on blackbody BB3500M of National Institute of Metrology (NIM), a bilateral spectral irradiance comparison was carried out between NIM and VNIIOFI (All Russian Research Institute for Optical and Physical Measurements) in the spectral wavelength from 250 to 2500 nm for the period of January 2015 to June 2016. The temperature measurement of the high temperature blackbodies were traced to the Pt–C and Re–C fixed point blackbodies and checked against the WC–C fixed-point blackbody for the two institutes respectively. The consistency of the temperature at 3021 K is better than 70 mK. The comparison result shows that the average relative deviation of spectral irradiance at 44 designated wavelengths is 0.45%. The consistency is better than 0.9% except the maximum deviation 1.1% at the wavelength of 2000 nm. The spectral irradiance units measured by NIM and VNIIOFI in this comparison are in agreement within the combined standard uncertainties of the laboratories over the wavelength range compared.