Basrur Sanjiva Rao
Articles written in Proceedings – Section A
Volume 4 Issue 1 July 1936 pp 10-10 Erratum
Volume 4 Issue 1 July 1936 pp 11-16
Volume 4 Issue 5 November 1936 pp 562-570
The effect of temperature of activation on the capillary space in alumina and ferric oxide gels has been studied. Structural changes in alumina gel have been noticed in the neighbourhood of 500°C. and 900°C. and their significance discussed.
Adsorption on alumina and ferric oxide gels from binary mixtures of liquids has been studied and the behaviour of these has been compared with that of silica. It is concluded that the chemical nature of a gel markedly affects selective adsorption from binary mixtures of liquids.
Volume 6 Issue 1 July 1937 pp 16-23
A microspring balance of quartz fibre of the McBain-Bakr type has been used for studying adsorption of vapours of water and pyridine on gels of silica and alumina.
The difference in adsorption on “glassy” and “chalky” gels of silica has been accounted for, by the wider capillaries in the latter.
Adsorption of pyridine on alumina gels activated at 400° C., 500° C. and 850° C. has been studied. The differences noticed are attributed to the variation in capillary size.
Volume 6 Issue 1 July 1937 pp 36-45
Dehydration of different varieties of rice has been studied employing for dehydration a current of hot air or vacuum desiccation over phosphorus pentoxide.
Sorption and desorption of water vapour by rice under isothermal conditions has also been studied in a modified form of the quartz spring microbalance devised by McBain and Bakr.
It is found that superior varieties of rice lose water more readily during dehydration and take up water at a faster rate and to a greater extent than varieties of poorer quality.
Rice obtained from paddy that has aged is capable of easier hydration and dehydration than a sample of the same variety from freshly harvested paddy.
The investigations indicate that the capillaries in superior varieties of rice are broader than those in inferior kinds. Storage of paddy seems to cause a widening of these capillaries.
Volume 6 Issue 1 July 1937 pp 46-51
Gold numbers and Congo rubin numbers of rice suspensions have been determined. Use of ammonia in place of potassium carbonate gives more satisfactory results in the preparation of gold sols by Zsigmondy's method.
Volume 6 Issue 1 July 1937 pp 52-58
The increase in conductivity with time of rice and rice powder suspensions in water has been studied at different temperatures. Varietal differences in the rates of increase have been observed, but they are not characteristic of quality. The increase in conductivity cannot be attributed to electrolytes liberated by hydrolysis of amylopectin as such hydrolysis is inappreciable, but is to be accounted for, by the dissolution of electrolytes already present in the free state in rice.
Volume 6 Issue 1 July 1937 pp 59-70
Clarification of muddy water by paste prepared from
Volume 10 Issue 1 July 1939 pp 20-30
A new method has been described for controlling the rate of formation of drops in the drop-weight method for the determination of surface tension and interfacial tension with mercury as one of the phases.
Interfacial tension of mercury has been measured in systems containing (
Volume 10 Issue 6 December 1939 pp 423-448
Volume 10 Issue 6 December 1939 pp 491-506
Volume 17 Issue 5 May 1943 pp 158-160
Volume 19 Issue 6 June 1944 pp 405-413
The study of the action of an electric field on the scattering intensity of sols has thus led to interesting results. The study is useful in determining the shape of the particles. The present technique would be supplementary to the studies of double refraction, in that the latter cannot be conveniently investigated in a highly scattering system. With slightly conducting sols, large fields can be used so as to produce saturation effects. Under such conditions, the use of rotating fields would bring about a unique orientation of the discs. A superposition of two A.C. fields of different cycles at right angles to each other would have the same effect as the circular field. The use of elliptical fields would reveal any want of equality of the two axes in the plane of discs of flat particles. The technique itself is simpler than the flow technique. Since there is often a large difference in the dielectric constant between the particles and the medium, the orientation is marked even with small fields, and the electric field is thus more powerful than the magnetic field in bringing about orientation.
Volume 23 Issue 1 January 1946 pp 1-7
The relative efficiencies of some of the common wetting agents have been determined by measuring the surface tension of five-minute-old surfaces of the solutions using the ring method in a modified form. Aqueous solutions giving a surface tension of 37 dynes per cm. may be considered to have good wetting properties. It is found that wetting power is not necessarily associated with detergent and emulsifying properties.
Salts greatly increase wetting power. Bivalent cations are more effective than univalent cations in increasing wetting power. A moderate degree of hardness in water employed in preparing solutions of wetting agents may be of advantage in the textile industry.
The maximum bubble pressure method is shown to be unsuitable for the measurement of surface tension of solutions which show a variation with time. A rough idea of the order of wetting efficiencies of wetting agents can however be obtained by measuring the surface tension of a five-second-old surface by this method.
Volume 23 Issue 1 January 1946 pp 8-15
Casein has been spread from its aqueous solutions by different methods and it has been found that the modified band method is the most suitable for the study of protein films.
Effect of salts on the spreading of casein has been studied. The results obtained can be explained on the basis that two different factors, solubility and the electric charge of the protein molecule influence spreading.
Treatment of the protein with formaldehyde causes a decrease in spreading. Change in pH affects spreading of formolised casein to a smaller degree.
Sodium metaphosphate diminishes markedly the spreading of casein. Trichloracetic acid, however, has no effect.
Deaminisation of casein alters the spreading properties and gives unstable films on acidulated water. No films can be got on distilled water.
The spreading properties of an isodisperse fraction of casein have been studied. The limiting area of this fraction has been found to be of the same order as that of the original material.
Volume 24 Issue 3 September 1946 pp 261-276
Volume 24 Issue 3 September 1946 pp 277-286