Selected Publications

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BYU Authors: Chuan-Hsi Hung, Landon A. Wiest, Bhupinder Singh, Anubhav Diwan, Michael J. C. Valentim, Robert C. Davis, and Matthew R. Linford, published in J. Sep. Sci.
Here, we report efficiencies up to 112000 plates per meter (a reduced plate height, h, of 2.22) for RP, carbon/nanodiamond/aminopolymer particles using conventional injection conditions in HPLC. This efficiency greatly exceeds our best previously reported value of 71000 N/m (h = 3.52). The carbon cores used in this study were derived from carbonized poly(divinylbenzene) spheres that were either made in-house by a two-step polymerization procedure or obtained commercially. The resulting particles showed good uniformity and were oxidized in nitric acid to increase their dispersability. X-ray photoelectron spectroscopy confirms particle oxidation and subsequent aminopolymer deposition. Layer-by-layer (LbL) growth of poly(allyamine) and nanodiamond was demonstrated to produce core-shell particles. After LbL growth, the particles were functionalized, sieved, and packed into columns. The column functionalization and packing were reproducible. Van Deemter curves indicated that the commercially obtained poly(divinylbenzene) spheres outperformed those synthesized in our laboratory. The columns appear to be stable at 120 degrees C in a pH 11.3 mobile phase. Longer columns (2.1 x 50 mm) than previously reported were packed. Four essential oils were separated by gradient elution.
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BYU Authors: Hao Wang, Barry M. Lunt, Richard J. Gates, Matthew C. Asplund, Robert C. Davis, and Matthew R. Linford, published in ACS Appl. Mater. Interfaces
A novel write-once-read-many (WORM) optical stack on Mylar tape is proposed as a replacement for magnetic tape for archival data storage. This optical tape contains a cosputtered bismuth–tellurium–selenium (BTS) alloy as the write layer sandwiched between thin, protective films of reactively sputtered carbon. The composition and thickness of the BTS layer were confirmed by Rutherford Backscattering (RBS) and atomic force microscopy (AFM), respectively. The C/BTS/C stack on Mylar was written to/marked by 532 nm laser pulses. Under the same conditions, control Mylar films without the optical stack were unaffected. Marks, which showed craters/movement of the write material, were characterized by optical microscopy and AFM. The threshold laser powers for making marks on C/BTS/C stacks with different thicknesses were explored. Higher quality marks were made with a 60× objective compared to a 40× objective in our marking apparatus. The laser writing process was simulated with COMSOL.
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BYU Authors: Barry M Lunt, Robert Davis, Matthew R. Linford, and Hao Wang, published in 10th International Conference on Preservation of Digital Objects, (Lisbon, Portugal, September 2013), ed. José Borbinha, Michael Nelson, Steve Knight.
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BYU Authors: H. Wang, B. M. Lunt, R. C. Davis, and M. R. Linford, published in Internationa Symposium on Optical Memory 2013, (Incheon, Korea, August 2013).
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BYU Authors: Felipe Rivera, Robert Davis, and Richard Vanfleet, published in Microsc. Microanal.
Transmission electron microscopy (TEM) and focused ion beam (FIB) are proven tools to produce site-specific samples in which to study devices from initial processing to causes for failure, as well as investigating the quality, defects, interface layers, etc. However, the use of polymer substrates presents new challenges, in the preparation of suitable site-specific TEM samples, which include sample warping, heating, charging, and melting. In addition to current options that address some of these problems such as cryo FIB, we add an alternative method and FIB sample geometry that address these challenges and produce viable samples suitable for TEM elemental analysis. The key feature to this approach is a larger than usual lift-out block into which small viewing windows are thinned. Significant largely unthinned regions of the block are left between and at the base of the thinned windows. These large unthinned regions supply structural support and thermal reservoirs during the thinning process. As proof-of-concept of this sample preparation method, we also present TEM elemental analysis of various thin metallic films deposited on patterned polycarbonate, lacquer, and poly-di-methyl-siloxane substrates where the pattern (from low-to high-aspect ratio) is preserved.
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BYU Authors: A. C. Pearson, B. M. Lunt, R. C. Davis, and M. R. Linford, published in International Symposium on Optical Memory 2013 (August 2013, Incheon, Korea)