title: Production and spectral properties of lattice defects in natural fibrous gypsum colored electrolytically at near room temperature using a pointed anode.
abstract: Natural fibrous gypsum is colored electrolytically at near room temperatures and under various voltages using a pointed anode and a flat cathode. The SO4(-), SO3(-), SO2(-) and O(-) lattice defects are produced in the colored natural fibrous gypsum. No visible characteristic absorption band in the ultraviolet and visible wavelength regions is observed in the optical absorption spectrum of the natural fibrous gypsum before the electrolytic coloration. The characteristic absorption bands of the SO4(-), SO3(-), SO2(-) and O(-) lattice defects are observed in the optical absorption spectra of the colored natural fibrous gypsum. The production of the lattice defects is explained. Current-time curve for the electrolytic coloration of the natural fibrous gypsum and its relationship with the electrolytic coloration processes are given.
authors: Department of Physics, Tianjin University, Tianjin 300072, PR China. jthgu@163.com
authors: Hongen
authors: H
authors: Gu
authors: Yutong
authors: Y
authors: Li
authors: Rui
authors: R
authors: Zhu
authors: Dongliang
authors: D
authors: Ma
authors: Pin
authors: P
authors: Tian
mesh_terms: D000042:Absorption; D002133:Calcium Sulfate / Q000737:chemistry*; D003116:Color; D004560:Electricity; D004566:Electrodes; D004572:Electrolysis / Q000379:methods*; D013057:Spectrum Analysis; D013696:Temperature; D013997:Time Factors
chemical_list: D002133:Calcium Sulfate