Low melting point alloy is a potential high-temperature heat transfer medium because of the high thermal conductivity, low solidus temperature and wide range of use temperature. Consequently, we investigated the possi...Low melting point alloy is a potential high-temperature heat transfer medium because of the high thermal conductivity, low solidus temperature and wide range of use temperature. Consequently, we investigated the possibility of using Sn-Bi-Zn-Ga alloys as heat storage and heat transfer material. Moreover, we investigated the microstructure and phase compositions by electron probe micro-analysis (EPMA) and X-ray diffusion (XRD). Results show that the new structures and phases are formed in the alloy matrix with Ga additions, which lead to the improvement of the thermal properties. An extensive thermophysical characterization of the Sn-Bi-Zn-Ga alloys has been performed by differential scanning calorimeter (DSC) analysis. The addition of Ga lowers the peak temperature and increases the heat capacity of the alloys. The thermal expansion of the test alloys increases with increasing temperature and the densities decreases with Ga additions. As the density, specific heat capacity and thermal diffusivity change with temperature and physical state, the thermal conductivity of the alloys first decreases and then increases. These results demonstrate the feasibility of using Sn-Bi-Zn-Ga alloys as the high-temperature heat transfer fluid.展开更多
目的通过电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法建立加味左金丸中Cd、Pb、As、Hg、Co、V、Ni、Cu、Li、Sb、Ba、Mo、Sn、Cr、Na、Mg、Al、Ca、Ti、Mn、Fe、Zn、Ga、Se、Sr、Tl共计26种无机元素...目的通过电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法建立加味左金丸中Cd、Pb、As、Hg、Co、V、Ni、Cu、Li、Sb、Ba、Mo、Sn、Cr、Na、Mg、Al、Ca、Ti、Mn、Fe、Zn、Ga、Se、Sr、Tl共计26种无机元素的测定方法。方法加味左金丸通过微波消解法处理后,根据相对分子质量的大小选择内标物,其中^(7)Li、^(23)Na、^(24)Mg、^(27)Al、^(40)Ca、^(48)Ti、^(51)V、^(52)Cr、^(55)Mn、^(56)Fe、^(58)Ni、^(59)Co、^(63)Cu、^(66)Zn、^(70)Ga、^(75)As、^(77)Se、^(86)Sr以^(72)Ge作为内标;^(95)Mo、^(114)Cd、^(118)Sn、^(121)Sb、^(137)Ba以^(115)In作为内标;^(202)Hg、^(205)Tl、^(208)Pb以^(209)Bi作为内标。对标准品溶液、空白溶液与供试品溶液进行分析,采用标准曲线法进行定量分析。通过ICP-MS法进行测定。结果26种无机元素线性的相关系数r≥0.9996,检出限为0.001~1.500μg/L,定量限为0.01~5.00μg/L,精密度与重复性试验的RSD均小于5%,平均回收率在82.64%~106.44%,RSD均小于5%。对3个厂家的12批样品进行了测定,26种元素的含量差异较大,其中Na、Mg、Ca、Fe 4种元素的含量比较高,均大于500μg/g,Cd、Pb、As、Hg、Co、Li、Sb、Mo、Sn、Cr、Se、Tl的含量比较低,均小于1μg/g。由结果可知,人体的常量元素,如Na、Mg、Ca的含量比较高,Cd、Pb、As、Hg等有害元素含量比较低。根据《中国药典》2020年版一部的要求,本品中Cd、Pb、As、Hg与Cu均符合规定。结论该方法快速、准确,可以用于加味左金丸中无机元素的测定。展开更多
基金Funded by National Key Technology Research&Development Program of China(No.2012BAA05B05)Key Technology Research&Development Program of Hubei(No.2015BAA111)Science and Technology Department of Hubei Province and the Fundamental Research Funds for the Central Universities(No.WUT:2017Ⅱ23GX)
文摘Low melting point alloy is a potential high-temperature heat transfer medium because of the high thermal conductivity, low solidus temperature and wide range of use temperature. Consequently, we investigated the possibility of using Sn-Bi-Zn-Ga alloys as heat storage and heat transfer material. Moreover, we investigated the microstructure and phase compositions by electron probe micro-analysis (EPMA) and X-ray diffusion (XRD). Results show that the new structures and phases are formed in the alloy matrix with Ga additions, which lead to the improvement of the thermal properties. An extensive thermophysical characterization of the Sn-Bi-Zn-Ga alloys has been performed by differential scanning calorimeter (DSC) analysis. The addition of Ga lowers the peak temperature and increases the heat capacity of the alloys. The thermal expansion of the test alloys increases with increasing temperature and the densities decreases with Ga additions. As the density, specific heat capacity and thermal diffusivity change with temperature and physical state, the thermal conductivity of the alloys first decreases and then increases. These results demonstrate the feasibility of using Sn-Bi-Zn-Ga alloys as the high-temperature heat transfer fluid.
