Osmotic dehydration assisted impregnation of curcuminoids in coconut slices

Osmotic treatment was explored as a method to infuse curcuminoids in coconut slices. The rate of mass transfer of moisture, solid and curcuminoids with or without application of ultrasound were studied over a range of concentration of osmotic solutions (0-50%). The diffusion coefficient of curcuminoids was 1.64 × 10⁻¹⁰ m²/s, when water was used in place of osmotic solute which was further enhanced by the application of ultrasound to 1.87 × 10⁻¹⁰ m²/s. Increase in the concentration of osmotic solution beyond 25% resulted in reversal in the direction of moisture and solid mass transfer. Ultrasound treatment resulted in higher moisture and solid mass transfer due to the breaking of cell structure as revealed by microstructure examination. HPLC analysis revealed that all the curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin) were infused into the coconut matrix. The present study concluded that osmotic dehydration is a feasible technology for impregnation of functional ingredients into foods without altering its matrix.     

Formulation of an improved smeared stiffener theory for buckling analysis of grid-stiffened composite panels

An improved smeared stiffener theory for stiffened panels is presented that includes skin-stiffener interaction effects. The neutral surface profile of the skin-stiffener combination is developed analytically using the minimum potential energy principle and statics conditions. The skin-stiffener interaction is accounted for by computing the bending and coupling stiffness due to the stiffener and the skin in the skin-stiffener region about a shift in the neutral axis at the stiffener. Buckling load results for axially stiffened, orthogrid, and general grid-stiffened panels are obtained using the smeared stiffness combined with a Rayleigh-Ritz method and are compared with results from detailed finite element analyses.     

Performance of a multiple-wick solar still with condenser

In a conventional still, because the water condenses underneath a glass cover, its temperature becomes quite high. During the period of maximum sunshine, the glass temperature is higher than the dew point of the air-vapour mixture inside the still. Thus the yields of these kinds of stills are low. In this communication we have investigated experimentally the performance of a still with a condenser. Most of the condensation now takes place in the condenser, consequently the glass temperature remains low causing less heat loss to the ambient environment. The yield of the condenser-type still is higher than that of the non-condenser-type still.     

Anisotropy of dielectric relaxation in poly(ethylene terephthalate) fibres

Dielectric measurements have been made on poly(ethylene terephthalate) (PET) fibres in the frequency range 0.5–10 kHz in temperature range ?120°?+30° C with the applied electric field parallel and perpendicular to the fibre axis. Considerable directional anisotropy was observed in the β-relaxation process, which was independent of frequency. The observed dielectric anisotropy has been related to the structural parameters thus leading to a value 〈cos²ψ〉 = 0.21, where ψ is the angle between the dipole moment vector responsible for this relaxation and the molecular chain axis. Activation energy for this process in PET fibres (9 kcal/mol) was lower than that reported for PET films and extruded rods.     

3D Integration for Introspection

In today's complex processors, specialized profiling and introspection hardware would be incredibly beneficial to software developers, but most proposals for its addition would increase the cost of every die manufactured. Modular, "snap-on" analysis hardware, stacked vertically with the processor die using a 3D interconnect, could be included with developer systems to assist in debugging and testing, and omitted from consumer systems to keep them economically competitive     

Support vector channel selection in BCI

Designing a brain computer interface (BCI) system one can choose from a variety of features that may be useful for classifying brain activity during a mental task. For the special case of classifying electroencephalogram (EEG) signals we propose the usage of the state of the art feature selection algorithms Recursive Feature Elimination and Zero-Norm Optimization which are based on the training of support vector machines (SVM). These algorithms can provide more accurate solutions than standard filter methods for feature selection. We adapt the methods for the purpose of selecting EEG channels. For a motor imagery paradigm we show that the number of used channels can be reduced significantly without increasing the classification error. The resulting best channels agree well with the expected underlying cortical activity patterns during the mental tasks. Furthermore we show how time dependent task specific information can be visualized.     

Effect of addition of polycarbonate on sheared flow of red mud-filled isotactic polypropylene

Different volume fractions of polycarbonate (PC) were incorporated to improve thermal stability of red mud (RM) filled polypropylene (PP). Effects of PC addition in RM filled PP on shear stress, melt viscosity, and melt elasticity have been determined under different shear rates by using a capillary rheometer. With the increase in shear rate, addition of PC in RM-filled PP reduced its shear stress and melt viscosity. However, recoverable shear strain increased with PC content in the blend.     

Dynamic mechanical characterization of PC/MWCNT composites under variable temperature conditions

A dynamic mechanical analysis has been performed on composite materials of polycarbonates (PC) and multi-walled carbon nanotubes (MWCNT) for evaluation of their mechanical hardness and storage modulus under the combined effects of variable loading frequencies and temperature conditions. The PC-based engineering machine components that are subjected to variable external loads and temperature conditions are not durable owing to the viscoelastic properties of PC. Composites of PC with MWCNT (2, 5 and 10 wt%) were fabricated and their mechanical characterization tests revealed that with increase in MWCNT composition both storage modulus and hardness enhanced significantly in comparison to pure PC. For 10 wt% PC/MWCNT composite, the average storage modulus increased in the range of 40–92%, while the average hardness was enhanced in a range of 88–121% for the combined effect of temperature range of 30–90 °C and loading frequency range of 30–230 Hz. With increase in temperature, the maxima of storage moduli and hardness for these composites shifted toward higher loading frequencies, indicating that these composites can be used for wider loading frequency range. Therefore, the experimental results of this paper have shown that the mechanical properties of PC-based composite materials with minor MWCNT compositions are enhanced significantly and hence can be used for automotive and aerospace engine parts where loading frequencies are high and temperature conditions are variable.