Mass Spectrometric Study of Stability, Thermochemistry and Structures of the Gaseous Oxyacid Salts
Experimental data obtained by Knudsen Effusion Mass Spectrometry and results of quantum-chemical calculations on the structure and thermodynamic properties of gaseous oxyacid salts were systematized. A criterion of thermal stability of these compounds was offered and regularities in the atomization enthalpies were established.
Mass spectrometric study of vaporization of cesium-containing borosilicate glasses
A mass-spectrometric Knudsen effusion method has been applied to study the vaporization behavior of three cesium-containing borosilicate glasses in the temperature range 845–1150 K. Vapor species of CsBO2(g) and Cs2(BO2)2(g) have been identified for the glass containing Cs2O, and NaBO2(g), Na2(BO2)2(g) and NaCs(BO2)2(g) have been identified in addition to CsBO2(g) and Cs2(BO2)2(g) for glasses containing Na2O and Cs2O. The vapor species of Na(g) has been further observed in the initial stage of heating to 1000 K. for the glass in which the mole ratio of Na2O plus Cs2O to B2O3 is larger than unity, while no vaporization of Na(g) occurs for the glass in which the ratio is equal to unity. Enthalpies of vaporization, enthalpies of formation and dissociation energies for the vapors and chemical activities of pseudo components in the glasses have been determined from the measured partial pressures and discussed by comparing with those for sodium borosilicate glasses, NaBO2(s) and CsBO2(s).
Convergence Anatomization of Aquaculture Production in Leading Fish-Producing Countries During the Period of 1997-2013
Growth and national importance of aquaculture production is empirically assessed as an important indicator of development. The present article aims to test whether the major aquaculture producing countries of the world are converging over time. The authors have applied the absolute and conditional beta convergence and sigma convergence approaches on the data of FAO for the period 1997-2013. The results show that there is an absolute beta convergence and sigma convergence among 25 major aquaculture producing countries; negative sign of coefficient of conditional beta convergence with per capita income is also noticed. It implies, the growth rates of aquaculture for developed nations are declining with rise in per capita income and backward fish-intensive countries are catching up with the giant producers like China and India. The cross-country variations are also going down which means that the countries' development gaps are getting narrowed by means of growth of aquaculture resources.