Effect of Slag Refining and Vacuum Treatment on the Main Impurities in Metallurgical Grade Silicon

造渣精炼和真空熔炼作为冶金法提纯太阳能级多晶硅的基本工艺，是去除工业硅中磷硼杂质和主要金属杂质的有效方法。由于磷硼杂质的化学特性不同，单个工艺不能同时有效地去除磷和硼。因此，必须将两种工艺加以组合优化以达到太阳能级多晶硅对关键杂质的纯度要求。 本论文将造渣精炼和真空熔炼两种提纯工艺进行组合优化，分析了组合工艺对多晶硅中杂质（尤其是杂质磷元素）去除效果的影响，研究了造渣精炼对真空挥发除磷工艺的影响规律，同时探讨了造渣精炼后主要杂质的赋存分布规律，并且结合理论分析了杂质磷在两种工艺过程中的变化规律和影响因素，通过工艺改进提高了除磷效果。其主要研究结果如下： 1、“造渣—真空”工艺更有利于工业硅...There are two basic ways of the metallurgical purification for solar grade silicon: slag refining and vacuum treatment, which are always effective methods to remove boron and phosphorus from the metallurgical grade silicon, respectively. However, due to the different chemical properties of boron and phosphorus, they can’t remove effectively by a single process. Therefore, the optimization combinat...学位：工学硕士院系专业：材料学院_材料加工工程学号：2072010115005

Hydrothermal synthetic ZnAl_2O_4 and Humidity sensing properties research

以Al2(SO4)3和zn(nO3)2为原料,采用水热法合成铝酸锌微粉体,通过扫描电镜和Xrd分析发现znAl2O4晶型良好,粒径小,呈纤维状均匀分布;进一步研究湿敏特性,结果表明:测试频率对阻抗-相对湿度(rH)特性曲线影响较大,阻抗随频率的增加而迅速减小,10kHz时在33%~95%的范围内曲线的线性度好,在相同的湿度下,试样的电容随频率的增加而减小,在低频100Hz下,电容随相对湿度的升高而增大。A simple hydrothermal was developed to fabricate ZnAl2O4 micro powder with Al2(SO4)3 and Zn(NO3)2 as raw materials,through the scanning electron microscopy(SEM)and XRD analysis found that the particles have good crystal shapesmall size,fibrous evenly distributed;Further researching the humidity sensing properties,the results show that test frequency have big effect on impedance-relative humidity(RH)characteristic curve,impedance decreases as frequency increases,the good linearity of the curve of impedance versus relative humidity appears at the frequency of 10KHZ,the capacitance of the sensor decreases as frequency increases in the same humidity and at low measurement frequency 100HZ,the capacitance increases as RH increases

聚苯胺纳米管在阳极氧化铝模板中电聚合的生长机理

利用阶跃电位、循环伏安等电化学方法,应用金属电沉积理论,研究聚苯胺纳米管在阳极氧化铝模板(AAO)内电聚合的生长机理.结果表明:电聚合初始,苯胺二维非扩散控制的瞬时成核生长形成聚苯胺晶胞链段单层,单层形成以后,聚苯胺的生长过程变为线性扩散控制.XRD实验进一步证实电聚合的聚苯胺同时包含结晶相和无定型相结构