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The CoSb3 and Y0.18Co4Sb12 compounds were synthesized by a metallurgical route. Their bulk materials were prepared by the hot-pressed process under vacuum. Thermoelectric properties of the samples were measured by the thermoelectric measurement system and the laser flash diffusivity apparatus. The carrier type conversion of hot-pressed CoSb3 was found at about 530 K, while the conversion was missed for the Y0.18Co4Sb12 sample. Electrical conductivity of the Y0.18Co4Sb12 sample increased due to the increase of carrier concentration, and its thermal conductivity decreased due to the enhancement of phonon scattering. The value of ZT, figure of merit, for the Y0.18Co4Sb12 sample was obviously enhanced due to positive contribution of the electrical conductivity and the thermal conductivity. 相似文献
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为了提高粉煤灰综合利用率,开发了一种以高铝粉煤灰为主要原料,赤泥为助溶剂,膨润土为粘结剂,采用高温烧结工艺制备高强陶粒的方法。通过正交试验探究不同原料配比及烧结制度对陶粒性能的影响。自制一种造孔剂,研究造孔剂添加量对陶粒性能的影响。采用扫描电子显微镜及X射线衍射仪对陶粒显微结构及物相组成进行分析。试验结果表明,在赤泥添加量为15%,膨润土添加量为5%,烧结温度1 290 ℃,烧结时间20 min条件下可制备出吸水率3.2%,筒压强度21.1 MPa的高强陶粒。通过调节造孔剂的添加量可以得到不同密度等级的高强陶粒产品,随着造孔剂含量增多,陶粒密度减小,强度降低,但仍能达到10 MPa以上。粉煤灰高强度陶粒的开发预期可为承重型建筑构件提供原料支撑。 相似文献
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采用固相反应和真空热压法,以CaSi2、Mg、Si为原料制备Ca取代的Mg2Si基热电材料,研究了钙取代对Mg2Si热电性能的影响。XRD结果表明Ca取代Mg2Si材料成相良好,测量了样品的电导率、Seebeck系数及热导率。由于Ca和Mg电负性、离子半径的不同,Ca对Mg位的替代对声子形成散射,降低了材料热导率,提高了其热电性能。 相似文献
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电动挖掘机控制系统的性能好坏直接影响整机的工作性能,现将电动挖掘机控制系统的特点及发展方向介绍如下,同读者分享。 相似文献
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