Prabhat K. Gupta
Ph. D., Case Western Reserve University, 1972
Tel. (614) 292-6769
Prof. Gupta has broad experimental
and theoretical interests in the understanding of inorganic glasses,
in particular oxide glasses. His interests can be broadly classified
into four areas:
1. Increased Reliability of Glasses: This work has focused on investigations of the structural, mechanical, chemical, and phase stabilities of glasses. The work on structural relaxation on glass fibers using Differential Scanning Calorimetry was recognized in the 1993 Otto Schott Research Award. The work on mechanical stability (Fracture and Tensile strength) has focussed on high strength reinforcement and optical glass fibers. The chemical stability (i.e., corrosion behavior) studies have been carried out on formed and annealed glass fibers showing for the first time a pronounced effect of the thermal history on the durability of glass fibers. The work on phase stability (crystallization and phase separation) has been carried out in halide glasses.
2. Process Modeling: Improvement in a manufacturing process requires modeling of the operation. Prof. Gupta has contributed in modeling of diffusion controlled processes such as homogenization and dissolution, of melt spinning of fibers, of energy efficiency of glass melting process, and of visco-elastic and constrained-viscous sintering processes.
3. Fundamental Studies in Glasses: Prof. Gupta has contributed much to the understanding of the glass transition phenomena, to thermodynamics and statistical mechanics of glasses, and to rationalizing the differing glass forming abilities of various compositions. In addition, he is interested in microscopic understanding of the structure and dynamics of simple glasses.
4. Novel Phenomena in Glasses:
His recent interests are in the areas of non-linear optical properties,
photo-induced effects, point defects in glasses, plastic deformation
at room and low temperature indentation in glasses, and intrinsic
and extrinsic roughness of glass surfaces made by different methods
(for example, melt-formed versus fracture surfaces).
Scanning electron micrographs of fracture surfaces collected during tensile testing. The failure stress was 108 ksi. (C) and (D) are the same as (A) and (B) but at a larger magnification. (A) and (B) are the two surfaces from a single break. The flaw is a platinum-rhodium crystal.
Selected Recent Publications
(with A. R. Cooper) "Topologically
Disordered Networks of Rigid Polytopes", J. Noncrystalline
Solids, 123, 14 (1990). "Corrosive Degradation of Glass
Fibers", Ceramic Transactions, 10, 141 (1990).
"A Simple Method for Measuring
the Friction Coefficient of Glass Fibers", J. Am. Ceram.
Soc., 74, 1692 (1991).
(with J. H. Huang) "Temperature
Dependence of the Iso-structural Heat Capacity of a Soda-Lime
-Silicate Glass", J. Noncrystalline Solids, 139, 239 (1992).
(with J. H. Huang) "Enthalpy
Relaxation in Thin Glass Fibers", J. Noncrystalline Solids,
(with T. Iwagoshi and S. Dregia) "Computer Simulation of Elastic and Fracture Behavior of NaCl Crystal", J. Am. Ceram. Soc., 76, 465 (1993).
(with S. F. Rosenstiel, R. A. van der Sluys, and M. H. Zimmerman) "Strength of Dicor Glass ceramic after Surface Coating", Dental Materials, 9, 274 (1993).
(with S. F. Rosenstiel, I. L.
Denry, W. Zhu, and R. A. van der Sluys) "Fluoroalkylethyl
Silane Coating as a Moisture Barrier for Dental Ceramics",
J. Biomedical Materials Research, 27, 415 (1993).
and Glass Forming Ability", J. Am. Ceram. Soc., 76, 1088
(with J. M. Corpus) "The Diameter Dependence of the Refractive Index of Melt-Drawn Glass fibers", J. Am. Ceram. Soc., 76, 1390 (1993). (with D. Inniss, C. R. Kurkjian, and D. Brownlow)
Notre-Dame de la Belle-Verriere' from the Cathedral of Chartres. Dr. Gupta's interests include many aspects of glass science, from the statistical mechanics of glasses to the topic "Do Cathedral Glasses Flow?" (see article by the same name co-authored by Dr. Edgar D. Zanotto in the American Journal of Physics)
"Determination of V-K Curves
from Static Fatigue Data", J. Am. Ceram. Soc., 77, 2445 (1994).
"Fractography of Fiberglass", in Fractography of Glass,
Eds R. C. Bradt and R. E. Tressler, Plenum Press, p.185 (1994).
(with C. H. Kuo) "Rigidity and Conductivity Percolation Thresholds in Particulate Composites", Acta Matall Mater., 43, 397 (1995).
"Noncrystalline Solids: Glasses and Amorphous Solids", J. Noncrystalline Solids, 195, 158 (1996).
"Topologically Disordered networks of Rigid Polytopes: Applications to Noncrystalline Solids and Constrained Viscous Sintering", in Rigidity Theory and Applications, Eds: M. F. Thorpe and P. M. Duxbury (1998).
(with E. D. Zanotto) "Do cathedral Glasses Flow? - Additional remarks", Am. J. Physics, (1999).
(with P. B. Macedo and R. K. Mohr) 4,181,403 "Optical Fiber with Compression Surface layer" (1980).
(with M. G. Drexhage and P. B. Macedo) 4,244,721 "Method of making Composite Borosilicate glass particles", (1981).