穿条式隔热型材抗剪特征值测量结果不确定度的评定

依据GB/T 28289-2012《铝合金隔热型材复合性能试验方法》,以穿条式隔热型材为例,对其纵向抗剪特征值测量不确定度的来源进行了分析及评定,并给出了扩展不确定度。     

定型隔热制品导热系数（水流量平板法）不确定度的评定

介绍了定型隔热制品导热系数（水流量平板法）不确定度的要素构成及各类不确定度分量的计算方法,并计算了各不确定度分量的自由度,得出合成不确定度和扩展不确定度。得到不确定度报告为：导热系数检测结果A=0．197W／（m·K）,扩展不确定度U=0．005W／（m·K）,包含因子k=2。     

铝合金建筑型材韦氏硬度测量不确定度评定

分析了铝合金建筑型材韦氏硬度测量的不确定度来源．对试验过程中的测量不确定度进行了评定。     

我国铝合金隔热型材国家标准发布

由福建省南平铝业有限公司联合6家单位负责起草的GB5237．6—2004《铝合金建筑型材第6部分隔热型材》国家标准于2005年3月1日正式实施。该标准结束了目前铝合金隔热型材尚无统一国家标准的历史，填补了国内空白。     

中空玻璃传热系数测定结果的不确定度评定

采用CD-8080型双试样导热系数测定仪按GB/T 22476—2008《中空玻璃稳态U值（传热系数）的计算及测定》中的防护热板法对某结构为6mm透明普通玻璃+12mm空气层+6mm透明普通玻璃的中空玻璃的稳态传热系数进行了测定,并依据JJF 1059-1999《测量不确定度评定与表示》对试验过程中影响测定结果的各不确定度分量进行了评定。结果表明:该中空玻璃的稳态传热系数为U=（2.8±0.2）W·m^-2·K^-1,包含因子k=2;其中,由标准板标定,确定加热单元计量部分平均热流量引入的不确定度为影响中空玻璃稳态传热系数测定结果准确度的主要因素,由温度测量引入的不确定度其次,由数值修约引入的不确定度最小。     

铝合金窗用聚酰胺隔热胶变形原因

在某穿条式隔热铝合金建筑型材的生产过程中,其聚酰胺隔热胶在复合部位发生变形。采用组分分析、微观分析、差式扫描量热分析、力学性能测试、红外光谱分析等方法分析了聚酰胺隔热胶变形的原因。结果表明：短碎的玻璃纤维与树脂的结合作用力较小;材料的成型温度不足、结晶程度低、熔融峰对应温度偏低使材料的力学性能变差,最终导致聚酰胺隔热胶变形。     

铝合金隔热型材用聚酰胺隔热条密度的测定

以铝合金隔热型材用聚酰胺隔热条为研究对象,比较了GB／T1033．1-2008规定的非泡沫塑料密度测定中的浸渍法与GB／T1423-1996规定的贵金属密度测试法所测得的结果,通过理论计算说明两者的偏差不是误差,而是由于公式应用不当引起的。GB／T1033．1-2008中的浸渍法只在极限情形,即金属丝的影响可忽略时才成立,一般试验条件并不满足此极限要求,而GB／T1423-1996中的贵金属密度测定法更具有合理性和普遍性。     

气体大流量标准装置的扩展不确定度评定

本文根据《测量不确定度评定与表示》（JJF1059-1999）中的规范化要求和有关数据,对国家原油大流量计量站成都天然气流量分站的气体大流量标准装置的测量不确定度进行了评定,结果表明该装置经过技术改造后的扩展不确定度不大于0．05％（P=0．95）。同1996年装置建立时的扩展不确定度0．1％（P=0．95）相比,又进一步提高了测量准确度。     

护肝片中五味子醇甲含量的测量不确定度分析

本文根据JJF1059—1999《测量不确定度评定与表示》、JJF1135-2005《化学分析测量不确定度评定》和CNAS—GL06：2006（化学分析中不确定度的评估指南》中的有关规定．对用HPLC法测定护肝片中五味子醇甲含量的测量不确定度进行了分析,以期找出影响不确定度的因素。对不确定度进行评估．为评价检测报告提供科学依据。     

石墨炉原子吸收法测定黄豆中铅含量的不确定度评定

本文使用石墨炉原子吸收光谱法检测黄豆中铅含量。对数学模型中各个参数进行不确定度来源分析,并系统地评定各因素的不确定度。结果表明,黄豆中铅含量为0．042mg/kg的样品,扩展不确定度为0．001mg／kg（k=2）,最终测量结果表示为（O．042±0．001）mg／kg。影响石墨炉原子吸收光谱法测定黄豆中铅含量结果不确定度的主要因素有校准曲线拟合、样品测量重复性、标准溶液本身及其配制过程,而样品定容体积、样品称重等影响相对较小。     

The Thermal Conductivity, Thermal Diffusivity, and Specific Heat of Liquid n-Pentane

The thermal conductivity and thermal diffusivity of liquid n-pentane have been measured over the temperature range from 293 to 428 K at pressures from 3.5 to 35 MPa using a transient hot-wire instrument. It was determined that the results were influenced by fluid thermal radiation, and a new expression for this effect is presented. The uncertainty of the experimental results is estimated to be better than ±0.5% for thermal conductivity and ±2% for thermal diffusivity. The results, corrected for fluid thermal radiation, are correlated as functions of temperature and density with a maximum uncertainty of ±2% for thermal conductivity and ±4% for thermal diffusivity. Derived values of the isobaric specific heat are also given.     

隔热条的轴钉应力开裂试验方法

隔热条是隔热铝合金建筑型材的关键部件,可用轴钉应力试验考察其在加工和使用过程中的适应性,选用切削液-清洗液联合浸泡法和清洗液浸泡法两种方法对隔热条进行了轴钉应力测试,并对比了方法的不同。结果显示:试样均未出现开裂现象,表明新版标准GB 5237.6-2012中规定使用更严格的方法(GB/T 23615.1-2009中规定的方法)来考察隔热条的耐轴钉应力开裂性是可行的。     

The Thermal Conductivity, Thermal Diffusivity and Isobaric Heat Capacity of Toluene and Argon

This paper presents absolute measurements for the thermal conductivity and thermal diffusivity of toluene obtained with a transient hot-wire instrument employing coated wires over the density interval of 735 to 870 kgm^–3. A new expression for the influence of the wire coating is presented, and an examination of the importance of a nonuniform wire radius is verified with measurements on argon from 296 to 323 K at pressures to 61 MPa. Four isotherms were measured in toluene between 296 and 423 K at pressures to 35 MPa. The measurements have an uncertainty of less than ±0.5% for thermal conductivity and ±2% for thermal diffusivity. Isobaric heat capacity results, derived from the measured values of thermal conductivity and thermal diffusivity, using a density determined from an equation of state, have an uncertainty of ±3% after taking into account the uncertainty of the applied equation of state. The measurements demonstrate that isobaric specific heat determinations can be obtained successfully with the transient hot wire technique over a wide range of fluid states provided density values are available.     

等离子喷涂ZrO2热障涂层的抗热震性能

为了进一步了解等离子喷涂ZrO2涂层的制备及失效控制措施,提高涂层的使用寿命,研究了涂层在水淬和火焰喷烧两种条件下的抗热震性能.结果表明:水淬条件下垂直裂纹主要分布在距涂层中心12mm范围内,随热震次数的增加,垂直裂纹最终进入次表层,靠近中心处裂纹扩展较快;火焰喷烧条件下垂直裂纹分布在距涂层中心10 mm范围内,随热震次数的增加,裂纹在表面层和次表层界面处发生偏转,中心处裂纹扩展较快;火焰喷烧条件下涂层的抗热震性能优于水淬下,涂层中孔隙的存在加速了两种条件下裂纹的扩展.     

圆柱基体热障涂层热冲击下失效的瞬态应力分析

用等离子喷涂方法在合金圆柱体上制备了热障涂层,并用水冷的方法进行了热冲击实验,试样的失效现象为轴向的开裂和剥落.利用有限元分析工具对热障涂层的热冲击进行模拟,通过对涂层内部应力随时间分布的分析发现:热冲击过程中陶瓷层表面的周向应力随着时间由拉转变为压,冷却初期陶瓷层的周向拉应力值较大,超过了陶瓷层的抗拉强度,因而淬冷初期的周向应力是导致轴向裂纹萌发的主要原因;陶瓷层与粘结层接触面上的径向拉应力与粘结层的氧化生长引起界面开裂;轴向裂纹和界面开裂共同导致陶瓷层的剥落.     

The Thermal Conductivity, Thermal Diffusivity, and Heat Capacity of Gaseous Argon

This paper presents new absolute measurements for the thermal conductivity and thermal diffusivity of gaseous argon obtained with a transient hot-wire instrument. Six isotherms were measured in the supercritical dense gas at temperatures between 296 and 423 K and pressures up to 61 MPa. A new analysis for the influence of temperature-dependent properties and residual bridge unbalance is used to obtain the thermal conductivity with an uncertainty of less than 1% and the thermal diffusivity with an uncertainty of less than 4%. Isobaric heat capacity results were derived from measured values of thermal conductivity and thermal diffusivity using a density calculated from an equation of state. The heat capacities presented here have a nominal uncertainty of 4% and demonstrate that this property can be obtained successfully with the transient hot wire technique over a wide range of fluid states. The technique will be useful when applied to fluids which lack specific heat data.     

Thermal Conductivity,Thermal Diffusivity,and Heat Capacity of Gaseous Argon and Nitrogen

Low-pressure thermal conductivity and thermal diffusivity measurements are reported for argon and nitrogen in the temperature range from 295 to 350 K at pressures from 0.34 to 6.9 MPa using an absolute transient hot-wire instrument. Thermal conductivity measurements were also made with the same instrument in its steady-state mode of operation. The measurements are estimated to have an uncertainty of 1% for the transient thermal conductivity, 3% for the steady-state thermal conductivity, and 4% for thermal diffusivity. The values of isobaric specific heat, derived from the measured thermal conductivity and thermal diffusivity, are considered accurate to 5% although this is dependent upon the uncertainty of the equation of state utilized.Paper presented at the Sixteenth European Conference on Thermophysical Properties, September 1–4, 2002, London, United Kingdom     

膜层厚度对Ag/TiO膜透光隔热性能的影响

采用磁控溅射工艺制备了玻璃基Ag/TiO_2膜,并研究了膜层厚度对其透光隔热性能的影响。结果表明:当Ag膜厚度由6.7 nm增加到9.5 nm时,红外光的平均透过率由42.06%减小到7.70%,隔热温差由1.9℃增大到5.7℃,而可见光的平均透过率则呈现出先增加后减少的变化趋势,当Ag膜厚度为7.7 nm时,复合膜的可见光平均透过率达最大值,为70.85%;当Ti O_2膜厚度由4.1 nm增加到16.7 nm时,红外光的平均透过率由34.12%增大到38.28%,而可见光的平均透过率与隔热温差均呈现出先增大后减少的变化趋势,当Ti O_2膜厚度为10.4 nm时,复合膜的可见光平均透过率达最大值,为70.85%,而厚度为13.6 nm时,膜的隔热温差达最大值,为5.2℃。