Solvothermal synthesis and thermoelectric properties of skutterudite compound Fe（0.25）Ni（0.25）Co（0.5）Sb3

Nanostructured skutterudite-related compound Fe0.25Ni0.25Co0.5Sb3 was synthesized by a solvothermal method using FeCl3, NiCl2, CoCl2, and SbCl3 as the precursors and NaBH4 as the reductant. The soivothermally synthesized powders consisted of free granules with an average particle size of tens of nanometers. The bulk material was prepared by hot pressing the powders. Transport property measurements indicated a heavily doped semiconductor behavior with n-type conduction. The thermal conductivity is about 1.83 W.m-1·K-1 at room temperature and decreases to 1.57 W.m-1·K-1 at 673 K. The low thermal conductivity is attributed to small grain size and high porosity. A maximum dimensionless figure of merit of 0.15 is obtained at 673 K.     

浅谈如何提高煤矿本煤层瓦斯抽放效果

目前提高本煤层瓦斯抽放率的技术途径主要有两个:(1)采用人为方法预先松动原始煤体,提高煤层的透气性;(2)合理布孔和改变钻孔参数。本文针对目前的本煤层抽放现状,对如何提高本煤层抽放效果,谈谈几点看法。     

浅谈钢管混凝土在建筑工程中的应用

钢管混凝土是一种新型的组合结构模式,即在钢管内填充混凝土,将两种不同性质的材料组合而形成的组合结构,在国内外的高层建筑和桥梁建筑等结构中得到了广泛的应用,本文主要介绍了钢管混凝土的发展概括、特点、施工与计算等方面的一些内容。     

波片最大双折射率温度系数测量

为研究波片最大双折射率随温度的变化情况。以云母波片为例,根据椭偏测量相位原理,利用椭偏仪的温控装置,对不同温度下云母波片的延迟量进行测量,再根据延迟量与最大双折射率的数学关系,得到相应温度下云母波片的最大双折射率。结果表明,在给定波长下,云母的最大双折射率随温度的增大而减小,用最小二乘法进行拟合求解出最大双折射率温度系数的表达式,该方法是测量最大双折射率的有效方法之一。     

Thermoelectric properties of MxMo6Te8 （M=Ag, Cu）

Ag and Cu filled Chevrel phase MxMo6Te8 (x=1.0, 2.0) samples were synthesized by direct solid state reaction and spark plasma sintering. The electrical and thermal properties were investigated in the temperature range of 300-800 K. The results show that both the electrical and thermal properties are affected by filler atoms. Although the electrical conductivity of MxMo6Te8 is slightly higher than that of state-of-the-art thermoelectric material, such as filled skutterudites, the absolute value of Seebeck coefficient is relatively low. Due to the phonon scattering by the filler atoms, the decrease of the thermal conductivity and the lattice thermal conductivity is obvious. As a result, the dimensionless figure of merit(ZT) is improved over the whole temperature region. The highest ZT value is 0.034 at 800 K for the AgMo6Te8 sample.     

浅析重复采动对开采沉陷的影响

介绍了重复采动的几种情况,分析了重复采动对岩层和地表移动的影响,对下沉系数等移动参数的变化机理进行了剖析,最后对重复采动情况提出了建议.     

基于等分圆弧滑面土质边坡 的稳定性极限分析方法

基于等分圆弧滑面的简化条件,采用土塑性极限分析理论,建立了土质边坡极限分析模型,并推导得到了 土质边坡稳定系数计算公式。该方法考虑了圆弧滑面的内能耗散率作用和边坡土体自重荷载、地震惯性力及孔 隙水压力所做的外功率作用,可以解决土质边坡稳定性分析问题,是一种改进的土质边坡稳定性评价极限分析 方法。     

云南电网枯水期AGC补偿容量计算

统计了云南电网枯水期发电厂参与AGC辅助服务市场的运行数据,提出了"AGC容量调用率"的指标,建议对AGC容量计算公式中的关键系数进行修正,通过实际运行数据对改进算法进行了检验。