Glassy samples with a composition of 40P2O5&ndash;30V2O5&ndash;(30-x)Li2O&ndash; xK2O, 0<x<30 (mol %) were prepared by the conventional melt quenching technique in two forms of bulk and blown film. X-ray diffraction patterns corroborated the amorphous feature of the samples. Density of samples was investigated by using Archimedes principle. Based on absorption and reflection spectra, indirect a...

In this paper we re-examine the alkali dependence of the fraction of four-coordinated borons (N4) in two series of glasses: alkali borates (0·4M2O.B2O3) and mixed lithium caesium borates (0·4(xLi2O+(1-x)Cs2O). B2O3). High field B MAS-NMR experiments were performed to maximise the accuracy of the present results. We found no evidence for an alkali dependence on N4 in either system. In each case ...

Addition of Li, Na, K and Cs to a 1.5 wt% Rh/Al,O, catalyst resulted in a decrease of the hydrocarbon formation rate, while the methanol formation rate was almost unaffected. The overall result is an increased oxygenate selectivity at a decreased total activity. The oxo-selectivity increased in the order unpromoted < Li < Na< K < Cs. The results suggest that the main role of the alkali promoter...

Leather processing is an important industry in China, and the discharge of chromium waste has been severely circumscribed. Though traditional processes for treating chromium waste have been widely used in tannery plants, technology adopting high efficiency and economic simultaneously is deficient. In order to develop an economic treatment for tannery waste, a mixed alkali of sodium hydroxide an...

Quaternary tungstate glasses containing K2O, Na2O and B2O3 have been prepared by melt quench technique and studied by IR and Raman spectroscopy. Raman and infrared spectroscopy have been employed to investigate the (30−x)Na2O–xK2O–10WO3–60B2O 3 glasses in order to obtain information about the competitive role of WO3 and B2O3 in the formation of glass network. IR spectral study reveals the exist...