Mass recovery of carbonated fabrics of glass fibres after isothermal heating

Acknowledgement: Authors acknowledge financial support from Latvian National Program IMIS2Leaching of Na+ ions in sodium oxide (Na2O) and silica (SiO2) containing glass is well investigated mainly due to its weak weathering. The object of this study was naturally (at room conditions) leached, steady state product on surface of sodium oxide-silica-alumina (Al2O3) glass fibers (in fabric) in a form of shell of "glyed" trona crystals as a result of interaction of leached Na+ ions and H2O and CO2 from atmosphere. There are presented results of continued former investigation of mass loss by isothermal heating of fabric and mass recovery in different atmospheres during the first phase of adsorption (at least 0.25h) without changes of state of crystals obtained during preheating at different temperatures. There are observed two ways of decomposition of trona (Na3H (CO3)2•2H2O) with its beginning at about 55-570C and 73-750C. The regression analysis of mass restoring in different atmospheres indicates to simultaneous and exponential mass increase by physical adsorption of CO2 and H2O having the different parameters of exponents vs time. Decomposition of trona is discussed in terms of parameters of exponent vs preheating temperature.Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART

EPR, optical and thermometric studies of Cr3+ ions in the α-Al2O3 synthetic single crystal

The optical spectra of a single crystal of α-Al2O3Cr3+ were studied in a wide temperature range. The crystal was demonstrated to have a potential for optical thermometric applications. Three ways of measuring temperature were tested and analyzed: i) luminescence intensity ratio of the R1 and R2 lines; ii) change of the full width of half maxima of the R1 and R2 lines, and iii) thermal shifts of the R1 and R2 lines maxima. The highest absolute and relative sensitivities were obtained at cryogenic temperatures. In addition, the thermal shifts of the R lines were analyzed using the McCumber-Sturge equation to estimate the Debye temperature and the electron-vibrational interaction parameter

Comparative Influence of Surface Tungstate Species and Bulk Amorphous WO 3 Particles on the Acidity and Catalytic Activity of Tungsten Oxide Supported on Silica

Accessed by 06/2015International audienc