CAREER: Determination of Glass Structure using Laser Induced Time of Flight Mass Spectroscopy

9733724 Affatigato学院早期职业发展项目将使用激光诱导飞行时间质谱仪(LITOF-MS)来确定氧化硼玻璃系统的短程和中程有序度。众所周知，纯氧化硼玻璃的网络中含有三配位的六方环。然而，关于玻璃中存在的硼的多少部分被束缚在这些环中，存在着分歧。飞行时间质谱图的直接反卷积将产生关于该玻璃中存在较大结构单元的有价值的信息，以及关于环群丰度的定量数据。碱性硼酸盐玻璃可以由各种较大的基团组成，包括由四配位的硼连接的链状和六角环。在不同组成的碱性硼酸盐玻璃中，这些较大的单元的存在和相对丰度将使用质谱仪进行测量。相同化学计量比的晶体将被研究并用作校准和分析的起点。在该项目的这一阶段，将研究掺杂剂(在玻璃中引入浓度低于1摩尔百分比的发色团)对激光照射下网络基团产量的影响。在项目的最后阶段，LITOF-MS将用于研究碱性硼硅酸盐玻璃。人们普遍认为，这些玻璃主要由硅酸盐和硼酸盐子网络组成，但关于掺杂剂的影响以及这两个网络之间是否存在相互作用的问题仍然存在。核磁共振数据在这些问题上提供了相互矛盾的证据，但LITOF-MS应该提供能够回答这些问题的数据。由于COE学院主要是一所本科院校，这项工作将与本科生一起进行，为他们提供难得的长期研究机会，接触材料科学的前沿工作。学生们将进行样品的制作和表征，以及飞行时间的测量。此外，外展计划将弥合学院和当地高中之间的差距。附近两所高中的高年级物理和化学班级将被带到校园进行年度访问和关于科学和工程职业的研讨会，并将有几次机会与本科生研究人员互动。这个职业项目将寻求回答关于使用激光诱导飞行时间质谱仪(LITOF-MS)检查短程和中程原子排列的硼氧化物玻璃的几个基本问题。该项目将帮助我们了解这些具有重要技术意义的材料的结构。本科生参与研究的表现将为他们提供材料研究的经验。***

9733724 Affatigato The Faculty Early Career Development project will use laser induced time-of-flight mass spectroscopy (LITOF-MS) to determine the short- and intermediate-range order of boron oxide-based glass systems. It is known that the network of pure boron oxide glass contains hexagonal rings of three-coordinated boron. Disagreement exists, however, regarding what fraction of the boron present in the glass is tied up in these rings. The straightforward deconvolution of time-of-flight mass spectra will yield valuable information regarding the presence of larger structural units in this glass, as well as quantitative data on the abundance of the ring groupings. Alkali borate glasses can be made up of a variety of larger groups, including chains and hexagonal rings linked by four-coordinated borons. The presence and relative abundance of these larger units in alkali borate glasses of varying compositions will be measured using the mass spectrometer. Crystals of the same stoichiometry will be investigated and used as starting points for calibration and analysis. During this stage of the project, the effect of dopants (chromophores introduced into the glass at concentrations below 1 molar percent) on the yield of network groupings upon laser irradiation will be examined. In the last stage of the project, the LITOF-MS will be used to study alkali borosilicate glasses. It is generally agreed that these glasses are made up mostly of silicate and borate sub-networks, but questions remain about the effect of dopants and if there is interaction between the two networks. NMR data yields contradictory evidence on these matters, but the LITOF-MS should provide data that can answer these questions. As Coe College is a primarily undergraduate institution, the work will be carried out with undergraduate students, providing them a rare long-term researc h exposure to cutting-edge work in materials science. The students will carry out the sample manufacture and characterization, as well as the time of flight measurements. In addition, outreach programs will bridge the gap between the College and the local high schools. The upper-level physics and chemistry classes of two nearby high schools will be brought on campus for yearly visits and seminars on careers in science and engineering, and will have several opportunities to interact with the undergraduate researchers. %%% This CAREER project will seek to answer several fundamental questions about boron oxide-based glasses using laser induced time-of-flight mass spectroscopy (LITOF-MS) to examine the short- and intermediate-range atomic arrangements. The project will help us understand the structure of these technologically important materials. The involvement of undergraduate students in the performance of the research will provide them with experience in materials research. ***