Comparison of Four Different Methods for the Analysis of Dietary Fiber in Winged Bean Seeds

Two chemical and two enzymatic procedures were evaluated with respect to efficiency of protein removal and consistency in yield and composition of soluble and insoluble dietary fiber from winged bean seeds, (cultivar TPT-2). Considerable variability was observed in the yield and composition of the fiber fractions, but the results became more consistent when contamination of the non-carbohydrate components (protein, ash and lignin) were accounted for in the calculations. The constituent sugars of polysaccharides were found to be similar in all four methods. Results indicated the need to critically optimize conditions to achieve efficient deproteinization and the need to differentiate “inherent” and “contaminating” protein.     

Polysaccharides of Winged Beans (Psophocarpus tetragonolobus [L.] DC), Variety TPT-2

Variety TPT-2 contains little or no starch. Hot water extraction of defatted and partially deproteinized flour yielded soluble and insoluble polysaccharide fractions in yields of 11 and 28%, respectively. Fractional precipitation of the soluble polysaccharides yielded a predominant Fraction I and a minor Fraction II. Fraction I contained 96% polysaccharide. Fraction II and the insoluble fraction contained 81 and 72% polysaccharide, respectively, the remainder being protein, ash and lignin. Fraction I polysaccharide is predominantly (76%) galactan, but it also contains 18% uranic acid. The Fraction II polysaccharide appears to be predominantly arabinogalactan, but contains 15% uranic acid. Cellulose (41%), galactan (25%), xylan (14%) and acidic polysaccharides (15%) predominate in the insoluble polysaccharides.     

Variation in grainy texture of commercial ghee in relation to laboratory ghee and its blends†

Ghee, a major Indian dairy product, has unique pleasing flavour and granular texture. Ten samples of commercial ghee were analysed for grainy texture, fatty acid composition and melting and crystallisation behaviour. These were compared with laboratory ghee and its blends with high melting fraction (HMF) or low melting fraction (LMF). Grain size and quantity of commercial ghee ranged from 0.200 to 0.330 mm and 1 to 40%, respectively, when incubated at 29 °C for 24 h. Laboratory ghee samples showed a grain size and quantity of 0.241 mm and 42%, respectively. Commercial samples with poor granularity had a lower level of saturated fatty acids, while those with bigger grains had a higher level of palmitic acid (>35%). The ratio of unsaturated to saturated fatty acids showed significant variation in these samples. Differential scanning calorimetric analysis of the samples also showed variation in melting and crystallisation behaviour. In general, the characteristics of commercial ghee with poor granularity resembled those of laboratory ghee blended with LMF while commercial ghee with bigger grains compared well with the ghee blended with HMF.     

Structural characterization of electrodeposited boron

Structural characterization of electrodeposited boron was carried out by using transmission electron microscopy and Raman spectroscopy. Electron diffraction and phase contrast imaging were carried out by using transmission electron microscopy. Phase identification was done based on the analysis of electron diffraction patterns and the power spectrum calculated from the lattice images from thin regions of the sample. Raman spectroscopic examination was carried out to study the nature of bonding and the allotropic form of boron obtained after electrodeposition. The results obtained from transmission electron microscopy showed the presence of nanocrystallites embedded in an amorphous mass of boron. Raman microscopic studies showed that amorphous boron could be converted to its crystalline form at high temperatures.     

A REVIEW OF THEORY AND EXPERIMENTS ON DIFFUSION FROM SUBMICROSCOPIC PARTICLES

Diffusion-controlled evaporation or growth of submicroscopic particles is considered theoretically and experimentally. The conditions for which Fick's law apply are elucidated for Knudsen aerosols, and Fick's law together with the Chapman-Enskog molecular theory of gases are applied to determine diffusivities and Lennard-Jones intermolecular force parameters from experimental data on single submicron aerosol evaporation. The experimental method involving light scattering from a single droplet suspended in an electric field is reviewed, and the results for diffusion-controlled and noncontinuum evaporation are presented. For Knudsen numbers greater than 0.05, where diffusion theory does not apply, evaporation rate data are compared with available theoretical and semi-theoretical equations. A recently published solution of the stationary Boltzmann equation, modified to include the collision integral, is shown to be in excellent agreement with our experimental data for dibutyl sebacate evaporating into nitrogen.     

Steady Free Surface Flow of a Fluid-Solid Mixture Down an Inclined Plane

The present work is an extension of the investigations performed by Massoudi and Anand (2001) Massoudi, M. 2001. On the flow of granular materials with variable material properties. Inl. J. Non-linear Mech., 36: 25–37.  [Google Scholar]. The free surface flow problem is studied here. Numerical solutions for steady free surface flow of a solid-fluid mixture down an inclined plane are presented. The problem is formulated using the mixture theory framework. The resulting set of three coupled nonlinear differential equations is nondimensionalized. A parametric study is conducted to understand the influence of the dimensionless numbers on the velocity and volume fraction. The maximum fluid velocity is found to decrease with increase in the ratio of the drag force to the viscous forces within the fluid phase (D₁). The fluid phase velocity was found to decrease with increase in the ratio of the drag force to viscous force within the solid component (D₂), and the corresponding solid phase velocity was found to increase.     

Rapid Solidification of Sm-Co Permanent Magnets

In this article, we report the microstructural evolution of rapidly solidified Sm-Co alloys from 4 to 16 at. pct Sm. We have observed a wide variety of phase formation and microstructures, ranging from primary Co dendrite formation to eutectic structures to the formation of the metastable SmCo₇ compound. In particular, we observed nonequilibrium formation of Co along with SmCo₇, whose presence caused a decrease in coercivity from ∼10 kOe to 500 Oe. Alloying elements reduced the scale of the microstructure, effectively offsetting the detrimental effects of the Co phase formation and leading to a recovery of the coercivity. The eutectic structure with Co rods surrounded by SmCo₇ provides a natural path to nanoscale hard/soft magnetic nanocomposites, where control of scale and phase content is critical. This article is based on a presentation made in the symposium entitled “Phase Transformations in Magnetic Materials”, which occurred during the TMS Annual Meeting, March 12–16, 2006, in San Antonio, Texas, under the auspices of the Joint TMS/MPMD and ASMI-MSCTS Phase Transformations Committee.

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