The influence of preparation conditions on the electrochemical behaviour of CuO in a Li/CuO cell

A dozen CuO samples prepared under various conditions and from different starting materials were evaluated as cathode materials for a primary Li/CuO cell. The “thin electrode” method was used for rapid evaluation of the samples. Both coulombic efficiency and discharge voltage depend considerably on the method of synthesis. No correlation was found between the specific surface area and the resistivity of the samples on the one hand and the cathode performance on the other. Best results were obtained from CuO prepared by the oxidation of Cu₂O under controlled temperature and time of oxidation.     

Characterization of a lectin-like protein isolated from Lachesis muta snake venom

A lectin-like protein was isolated from L. muta venom by gel filtration on BIO Gel P-100 followed by column Chromatography on DEAE-sephades A-50. The protein eluted at 0.4 M Nacl in 0.01 Tris pH 7.3 and exhibited agglutinin activity toward 0+ human erythrocytes. The protein is a dimer with Mr 28 kDa. Amino acid analysis revealed high content of tryptophan and acid recidues and low content of cysteine and methionine residues. No neutral carbohydrates and sialic acid were detected. Circular dichroic spectrum shows 78% of B structure and 1% of alpha structure. In vitro experiments with erythrocytes from rat, rabbit and dog revealed strong agglutination while red blood cells from mice, sheep and goat were not agglutinated. In vivo experiments using anesthetized rats, a sharp and prolonged fall in the blood pressure was observed at protein dose of 1.5 mg/kg. Double dose of protein caused the death of the animal.     

Hindered and compression settling: parameter measurement and modelling.

The Vesilind settling velocity function forms the basis of flux theory used both in state point analysis (for design and capacity rating) and one-dimensional dynamic models (for dynamic process modelling). This paper proposes new methods to address known shortcomings of these methods, based on an extensive set of batch settling tests conducted at different scales. The experimental method to determine the Vesilind parameters from a series of bench scale settling tests is reviewed. It is confirmed that settling cylinders must be slowly stirred in order to represent settling performance of full scale plants for the whole range of solids concentrations. Two new methods to extract the Vesilind parameters from settling test series are proposed and tested against the traditional manual method. Finally, the same data set is used to propose an extension to one-dimensional (1-D) dynamic settler models to account for compression settling. Using the modified empirical function, the model is able to describe the batch settling interface independently of the number of layers.     

Stoichiometric dye-binding procedure for the determination of the reactive lysine content of soya bean protein

A new analytical method has been developed for the determination of the reactive lysine content of soya bean protein. The method is based on the reaction of the free basic groups of the protein with 1-phenylazo-2 naphthol-6,8 disulphonic acid. With regard to the stoichiometry of the procedure, it has been proved, contrary to earlier reports, that the basic amino acids, histidine, arginine and lysine, each combine with one mole of the dye. After acylation with propionic anhydride lysine alone loses its dye reactivity. The usefulness of the proposed method has been demonstrated by the determination of the reactive lysine content of several untreated, heat-treated and acid-treated soya bean samples. The results show that heat damage of about 5% in reactive lysine content can be measured in 1·5 h with good reproducibility.