Bi2SiO5的亚稳定相平衡的研究

通过ＤＴＡ和ＸＲＤ研究了Ｂｉ２Ｏ３－ＳｉＯ２系统及其化合物Ｂｉ２ＳｉＯ５（１：１相）的亚稳定平衡，发现亚稳和Ｂｉ２ＳｉＯ５的析晶温度大约为８４５℃，在Ｂｉ２Ｏ３－ＳｉＯ２系统的广泛区域内（ＳｉＯ２摩尔比数大于３０％）熔体冷却时易于自发成核析出Ｓｉ２ＳｉＯ５相，并且该相在进一步冷却时无其它相变产生，直到室温下也可稳定存在。     

PZTS系凝胶玻璃及玻璃陶瓷的结构研究

采用溶胶凝胶工艺在低温下合成均匀透明的ＰＺＴＳ新型多组元凝胶玻璃，并在凝胶玻璃中成功地析出ＰｂＴｉＯ３，Ｐｂ（Ｚｒ，Ｔｉ）Ｏ３纳米微晶。利用ＩＲ谱分析了凝胶玻璃中Ｓｉ－Ｏ－Ｓｉ，Ｓｉ－Ｏ－Ｔｉ等化学键在成胶过程中的形成以及在热处理过程中的变化，根据Ｋｉｓｓｉｎｇｅｒ原理估算了ＰＴＳ凝胶玻璃的析晶活化能。借助ＸＲＤ较系统地研究了凝胶玻璃在高温下的结晶结构。探讨了在ＰＺＳ、ＰＺＴＳ体系中ＺｒＯ２和Ｓｉ     

晶界非晶晶化法制备SiC／晶化玻璃纳米复合材料

以纳米ＳｉＣ颗粒为主晶相，锂铝镁硅玻璃为晶界相，用晶界非晶晶化法制备了ＳｉＣ％３０％晶化玻璃纳米晶复合材料。玻璃相含量，热压温度和热压压力是影响致密化的主要因素，适当的热处理使晶界玻璃析出纳米晶。     

MgO－B_2O_3－SiO-2渣中含硼组分晶化动态研究

采用透射电子显微镜原位加热（ｉｎｓｉｔｕＴＥＭ）观察技术研究了非晶态ＭｇＯＢ２Ｏ３ＳｉＯ２渣中含硼组分动态晶化过程。实验结果表明，非晶态ＭｇＯＢ２Ｏ３ＳｉＯ２渣晶化时，首先发生分相，然后２ＭｇＯ·Ｂ２Ｏ３晶体析出，继而３ＭｇＯ·Ｂ２Ｏ３晶体析出。同时也发现电子束辐射对晶化过程有很大影响     

MgO—B2O3—SiO2渣中含硼组分晶化动态研究

采用透射电子显微镜原位加热（ｉｎ ｓｉｔｕ ＴＥＭ）观察技术研究了非晶态ＭｇＯ－Ｂ２Ｏ３－ＳｉＯ２渣中含硼组分动态晶化过程。实验结果表明，非晶态ＭｇＯ－Ｂ２Ｏ３－ＳｉＯ２渣晶化时，首先发生分相，然后２ＭｇＯ·Ｂ２Ｏ３晶体析出，继而３ＭｇＯ·Ｂ２Ｏ３晶体析出。同时也发现电子束辐射对晶化过程有很大影响。     

中,高温钛乳浊釉显微结构的研究

应用ＸＲＤ、ＴＥＭ、ＳＡＤ及ＥＤＳ等测试技术，系统地研究了ＴｉＯ２及烧成温度对Ｋ２Ｏ－Ｎａ２Ｏ－ＣａＯ－ＭｇＯ－ＺｎＯ－Ａｌ２Ｏ３－ＳｉＯ２系瓷釉显微结构的作用。结果表明，在１１４０－１２２０℃烧 ，瓷釉中都存在分相与析晶现象，液滴相富含Ｔｉ＾４＋、Ｃａ＾２＋、Ｚｎ＾２＋而基体玻璃相富含Ｓｉ＾４＋，析出的晶体主要为钛榍石。随烧成温度的提高，析出晶体的数量不断减少。另外，当ＴｉＯ２加入量增加时瓷釉的     

中,高温钛乳浊釉显微结构的研究

应用ＸＲＤ、ＴＥＭ、ＳＡＤ及ＥＤＳ等测试技术，系统地研究了ＴｉＯ２及烧成温度对Ｋ２Ｏ－Ｎａ２Ｏ－ＣａＯ－ＭｇＯ－ＺｎＯ－Ａｌ２Ｏ３－ＳｉＯ２系瓷釉显微结构的作用。结果表明，在１１８０℃—１２２０℃烧成时，瓷釉中都存在分相与析晶现象，液滴相富含Ｔｉ４＋、Ｃａ２＋、Ｚｎ２＋，而基体玻璃相富含Ｓｉ４＋，析出的晶体主要为钛榍石。随烧成温度的提高，析出晶体的数量不断减少。另外，当ＴｉＯ２加入量增加时瓷釉的分相程度、液滴数量及尺寸将随之增大。     

三组份锂质瓷烧成中的物相变化

本文研究了三组份锂质烧烧成过程中的物相变化。试验证明：１０００℃以β－锂辉石与Ａｌ－Ｓｉ尖晶石，石英反应生成β－锂辉石固体，随温度升高，β－锂辉石固溶体中ＳｉＯ２量增加，其ｄ（２０１）值变小；降温过程中，β－锂辉石固溶体从液相中析出，析晶速度较快时，其ｄ（２０１）值较小。     

CaO—Al2O3—SiO2系统玻璃晶化时首析晶相及TiO2的作用机理预测和…

通过ＣａＯ－Ａｌ２Ｏ３－ＳｉＯ２系统玻璃的结构分析预测玻璃晶化时首析晶相是钙长石。选取ＣａＯ－Ａｌ２Ｏ３－ＳｉＯ２三元相图成玻璃区内的某点作为基础玻璃的组成，在基础玻璃吕加入ＴｉＯ２。用ＤＴＡ，ＸＲＤ和ＳＥＭ方法的研究结果表明，不玻璃中加ＴｉＯ２与否，晶化时首先析出的晶相都是钙长石，且均为从表面向内部生长，驰预测相符。     

Si－C－O－N系统相稳定性和相稳定性图

对Ｓｉ－Ｃ－Ｏ－Ｎ系统进行了平衡状态下的相稳定性计算，绘制了在１４７３Ｋ和１５７３Ｋ下的Ｓｉ３Ｎ４、ＳｉＣ、Ｓｉ２Ｎ２Ｏ和ＳｉＯ２相稳定性与Ｎ２分压和Ｏ２分压的关系图以及Ｎ２分压和ＳｉＯ分区的关系图，Ｓｉ３Ｎ４／Ｓｉ２Ｎ２Ｏ／ＳｉＣ、ＳｉＯ２／Ｓｉ２Ｎ２Ｏ／ＳｉＣ两个三固相平衡点与Ｎ２分压、Ｏ２分压和ＳｉＯ分压以及温度的函数关系日。并以此确定Ｃ纤维－ＳｉＣ纤维转变和Ｃ纤维上涂层ＳｉＣ过程中，为获得稳定ＳｉＣ相的气体分压。     

Low-Temperature Purification of Silicon by Dissolution and Solution Growth in Sodium Solvent

Efficient low-cost processes for solar-grade Si production are needed to overcome the deficiency in the supply of Si. We have demonstrated a new method for the purification of Si crystal. Low-purity Si powder was dissolved in a Na melt (solvent), and Si grains were crystallized by Na evaporation from the Na-Si solution at 1173 K. Glow discharge mass spectrometry analysis revealed that the concentrations of impurity elements, except Na and B, were decreased in the crystallized Si grain. In particular, the concentration of Fe which was mainly included in the Si powder decreased from 3200 ppm by mass to 1.5 ppm by mass in a refined Si grain. Iron disilicide was crystallized from the solution before the crystallization of Si. It was suggested that impurities were reduced not only by crystallization from the Na-Si melt but also by the dissolution of Si into the melt. Na contaminating the refined Si grain was eliminated down to 0.055 mass ppm by heating at 1723 K under vacuum.     

纳米Si3N4—SiC复相陶瓷显微结构

本文系统地研究了纳米Si_3N_4-SiC复相陶瓷显微结构,观测了纳米Si_3N_4-SiC复相陶瓷中Si_3N_4、SiC粒子晶粒尺寸,研究了复合在Si_3N_4晶粒内和晶界上的SiC粒子分布情况及Si_3N_4与SiC、Si_3N_4间的相界面。     

共聚法制备聚硅硼酸铝铁絮凝剂及其絮凝性能研究

以硅酸钠为主要原料共聚法合成了絮凝剂聚硅硼酸铝铁,研究了絮凝剂的最佳制备条件及其对CODCr的去除效果。实验结果表明：絮凝剂中Al3＋/Si、Fe3＋/Si和B/Si物质的量比分别为1︰2、1︰1和1︰10时聚硅硼酸铝铁的絮凝效果最好。在最佳制备工艺下制备的絮凝剂的用量为130 mg/L,废水pH为6~8的条件下,对印染废水中CODCr的去除率高于60%。     

硅烷偶联剂总硫含量与平均硫链长度的测试

研究固体和液体偶联剂Si69总硫含量与平均硫链长度的测试方法。采用元素分析仪,以管式炉燃烧-红外吸收法测试偶联剂Si69的总硫含量;用质量分数为0.04%的四丁基溴化铵/乙醇/甲醇溶液(体积比为18/45/137)作为流动相,C₁₈柱分离,等度洗脱的方式,采用高效液相色谱仪测试偶联剂Si69的平均硫链长度。结果显示:固体偶联剂Si69试样的总硫含量为11.512%,平均硫链长度为3.59;液体偶联剂Si69试样的总硫含量为21.924%,平均硫链长度为3.60;固体偶联剂Si69总硫含量的测试精密度比液体偶联剂Si69高。     

硅烷偶联剂Si69对SSBR/SiO2硫化胶热空气老化性能的影响

研究了SSBR(溶聚丁苯橡胶)/SiO2硫化胶热空气老化过程中,硅烷偶联剂Si69对其力学性能、应力松弛、交联密度及喷霜的影响。结果表明,加入Si69可以提高SSBR/SiO2硫化胶的力学性能、应力松弛系数和交联密度,并随Si69用量的增加而持续提高。加入Si69还可以减小热空气老化过程中硫化胶的应力松弛系数和交联密度的增长率,该增长率随Si69用量的增加而减小。加入Si69可以减轻硫化胶的喷霜现象,硫化胶表面的喷出物主要为白炭黑。     

Fabrication of Ni-silicide/Si heterostructured nanowire arrays by glancing angle deposition and solid state reaction

This work develops a method for growing Ni-silicide/Si heterostructured nanowire arrays by glancing angle Ni deposition and solid state reaction on ordered Si nanowire arrays. Samples of ordered Si nanowire arrays were fabricated by nanosphere lithography and metal-induced catalytic etching. Glancing angle Ni deposition deposited Ni only on the top of Si nanowires. When the annealing temperature was 500°C, a Ni₃Si₂ phase was formed at the apex of the nanowires. The phase of silicide at the Ni-silicide/Si interface depended on the diameter of the Si nanowires, such that epitaxial NiSi₂ with a {111} facet was formed at the Ni-silicide/Si interface in Si nanowires with large diameter, and NiSi was formed in Si nanowires with small diameter. A mechanism that is based on flux divergence and a nucleation-limited reaction is proposed to explain this phenomenon of size-dependent phase formation.     

Improving the performance of silicon anode in lithium-ion batteries by Cu2O coating layer

The influence of a 200 nm Cu₂O coating layer on the electrochemical performance of an 800 nm Si thin-film anode was investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge/discharge measurements. The electrochemical performance of the Si thin-film anode was improved by the coating layer. The coated Si anode exhibited higher values of conductivity in comparison with the pristine Si anode. Scanning electron microscopy images of the anodes after cycling test showed that the coated Si anode after cycling test had less cracks than the pristine Si anode. The galvanostatic charge/discharge measurements reveal that the cyclability and rate capability of the coated Si thin-film anode were better than the pristine Si thin-film anode.     

Deposition and characteristics of iron–silicon thin film catalyst for CNT growth

Fe–Si catalyst thin films for the growth of carbon nanotubes were prepared using co-sputter deposition. As-deposited Fe–Si films consist of different amounts of α-Fe and amorphous Si. The amount depends on the Si concentration in the film. Hydrogen plasma etched Fe–Si films become particles having different sizes. The particle size is also dependent on the Si concentration. Correlation among the Si concentration, the particle size, and the growth rate of carbon nanotube was made. Optimal growth of carbon nanotubes at 370 °C was obtained at an average particle size of 45 nm or a Si concentration of 21%.     

Effects of the temperature of hot isostatic pressing treatment on Cr–Si targets

Commercial as-hp (hot pressing) treated Cr–Si targets are used throughout this study, with three different compositions: Cr20–Si80, Cr35–Si65 and Cr50–Si50. To evaluate the effects of microstructure and properties of as-hp treated Cr–Si targets by hot isostatic pressing (HIP) SEM, XRD and porosity inspections were performed. The experimental results showed that the 1373 K, 1750 MPa, 4 h HIP treated with three different Cr–Si targets had suppressed porosities successfully. The most efficient was Cr50–Si50 target subjected to HIP treatment. Porosity decreased about 60% after HIP treatment, and both the nitrogen and oxygen concentrations of the targets were slightly increased after HIP treatment. This was especially true for the single silicon in Cr–Si targets such as Cr20–Si80 and Cr35–Si65. The aim of this paper is to discuss these methods and finding suitable temperatures for the HIP for Cr–Si targets.