Presidential Young Investigator Award: Chemical Diffusion and Oxidation Kinetics in Silicate Glasses

该项目涉及在硅酸盐玻璃和玻璃陶瓷中化学扩散对成核/玻璃稳定性的影响的实验研究。本研究的主要重点是表征铁的氧化/还原机理和动力学。承载硅酸盐玻璃及铁价态对玻璃稳定性和结晶成核的影响。这项研究的结果应该建议新的方法来制备玻璃。陶瓷材料通过“可控氧化”，即应用/操纵氧的化学势梯度来驱动化学扩散，从而在玻璃中进行结构重排和结晶成核。控制氧化还会影响玻璃+晶体体系的平衡织构；控制这种纹理的能力，从而控制玻璃陶瓷的某些物理特性。氧化/还原研究将包括玄武岩成分的玻璃（包括人造的和天然的），试图描述氧化还原条件对基性岩浆中化学扩散和结晶成核动力学的影响。

The project deals with an experimental study of nucleation/glass stability as affected by chemical diffusion in sililicate glasses and glass.ceramics. The primary emphasis of the study is to characterize the mechanism(s) and kinetics of oxidation/reduction in iron.bearing silicate glasses and the effect of the valence state of iron on glass stability and crystalline nucleation. The results of this research should suggest novel approaches to the preparation of glass.ceramic materials through `controlled oxidation', i.e., the application/manipulation of a chemical potential gradient of oxygen to drive chemical diffusion and consequent structural rearrangement and crystalline nucleation in the glass. Controlled oxidation should additionally affect the equilibrium texture in the glass.plus.crystalline system; the ability to control this texture, and therefore control certain physical properties of the glass.ceramic. The oxidation/reduction studies will include glasses of basaltic composition (both fabricated and natural) in an attempt to characterize the effect of redox conditions on the kinetics of chemical diffusion and crystalline nucleation in mafic magmas.