Search Results
Abstract
Properties of limestone related to SO2/SO3 reactivity were investigated. Limestone calcined under different conditions (temperature, time and with/without additives) yield calcines of distinctly different physical structures. The amount of pores and the size of the pores formed during calcination is important. The main purpose of the present work was to gain a better understanding and more reliable explanation of the temperature regime for gas desulphurization using Ca-based sorbents in atmospheric fluidized-bed combustors. Pore size, surface area and pore volume of each calcine were determined by mercury porosimetry and BET methods. At higher calcination temperature and during longer time, sintering became significant and the obtained calcine had a smaller internal surface area and thereby the average pore radius increased. The additives such as NaCl also accelerated sintering thus increasing the pore size. The measurements of porosity were supplemented by scanning electron microscopic observations employed for qualitative description of the pore structure. SEM micrographs are presented.
CoO/Al2O3 catalysts containing amounts of cobalt ranging form 2 to 20% were prepared atpH 11 from neutral mesoporous alumina composed of γ-Al2O3 and poorly crystalline boehmite, and were then dried at 80‡C. X-ray diffraction, DTA and TG techniques were used to study the structural changes produced upon thermal treatment up to 700‡C.
The research presents the effect of novel edible coatings based on low molecular weight chitosan on some properties of fresh-cut melon fruits – weight loss, total soluble solids, total acidity, mechanical strength and bacteria growth. Three different compositions were used as coatings – pure chitosan, chitosan and Ca lactate and alginate/chitosan multilayers. It was shown that the additional alginate layer substantially improves the protective properties of pure chitosan coating, resulting in preservation of cell structure. Negligible negative effect on the antibacterial activity of pure chitosan is demonstrated.
Abstract
Asymmetry of the relative line intensities in the57Fe. Mössbauer spectra of powdered samples of Na3[Fe/CN/5NH3]3H2O is reported. It is shown that the effect is due to a prefered orientation of the electric field gradient /EFG/, which is assumed to have a conical distribution around the normal of the absorber plane. Using this model for the EFG distribution the angle between the EFG and the normal of the absorber plane is determined.
The grotesque and the theatrical, as essential facets of Ligeti’s oeuvre, become more evident in his Violin Concerto than in most of his works from the 1980s. The analysis shows how these facets find expression on different levels of the composition — from the harmonic and rhythmic pre-settings over the compositional detail to the individual interpretation of the Violin Concerto as a genre and the formal dramaturgy.
Introduction Hazelnut spreads are considered as a complex multiphase system, which contain different dispersed solid particulars and a continuous fat phase ( Glicerina et al., 2013 ). The physical attributes such as textural properties, viscosity