• R K Gupta

Articles written in Proceedings – Section A

• Chemical examination of the leaves ofDiospyros melanoxylon Roxb.

The leaves ofDiospyros melanoxylon Roxb. growing in Mysore, have been shown to contain ceryl alcohol, lupeol, betulin,β-sitosterol, sequoyitol, a new triterpene alcohol, m.p. 212–13°, and a new triterpene carboxylic acid named diospyric acid, m.p. 272–74°.

Note (Correction added at the proof stage.)—When this paper is under print, a note has appeared from Rowet al. (Row, L. R., Rao, C. S. and Ramaiah, T. S.,Curr. Sci., 1964,33, 367), wherein it is stated that lupeol and betulin occur along with betulinic acid in the ebony ofD. melanoxylon also.

• A new polarographic method for estimation of anionic surface active compounds in technical sugar solutions using cation-exchange resin

Solutions of white consumption and khandsari sugar, jaggery and molasses were passed through cation-exchange resins, to eliminate the possibility of reduction of cationic substances during polarographic analysis. The solution thus obtained showed well-defined polarograms. The half-wave potential of all such technical sugar solutions was found to be ≃ 1·5 volt. The straight lines obtained between diffusion current and concentration showed the possibility of quantitative estimation of the substance reduced, which appeared to be some anionic surface active compound present in the systems. The irreversible nature of reductions of the sufrace active compounds was established. The importance of the reduction with similar half-wave potential in establishing the role of anionic substances in many sugar technological problems are expected to be established by this approach. The white consumption sugars were characterised by absence of any polarographic wave. The concentration of the reducible substance was found more in molasses than in jaggery and still less in khandsari.

• A finite transform involving generalized prolate spheroidal wave functions and its applications

The author has extended his previous results pertaining to spheroidal functions by introducing a new finite transform involving generalized prolate spheroidal functions. The inversion has also been found. In the end its application has also been given in solving certain boundary value problems.

• Generalized prolate spheroidal wave functions

The following equation$$(1 - x^2 )d^2 y/dx^2 + [(\beta - \alpha - (\alpha + \beta + 2)x]dy/dx + (\chi (c) - c^2 x^2 )y = 0$$ has been solved wherex(c) a separation constant is the characteristic value and is a function ofc. This solution is a generalization of spheroidal wave function into the series form ofPnα;β (x),α andβ both separately are greater than −1. The finite transform and its properties have been defined and a boundary value problem has been solved applying these tools.

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