Thermelectric power in ultrathin films ofA 3 II B 2 V semiconductors in the presence of a quantizing magnetic field

An attempt is made to study theoretically the thermoelectric power in ultrathin films ofA ₃ ^II B ₂ ^V semiconductors in the presence of a quantizing magnetic field by formulating a new magneto-dispersion law, within the framework ofk · p formalism incorporating the anisotropies in the band parameters. It is found, taking ultrathin films ofn-Cd₃P₂ as an example, that the same power decreases with increasing surface electron concentration and changes in an oscillatory manner with film thickness and quantizing magnetic field. In addition, the well-known results for parabolic energy bands have also obtained from our expressions as special cases.     

Polygonal deformation of a metallic foil subjected to impact by an axisymmetric indenter

When a stack consisting of layers of soft elastomer and thin metallic film is subjected to low intensity impact by releasing an axisymmetric spherical indenter from a vertical height, the foils buried within the stack undergoes large deformation and fracture. The shape of the deformed area nevertheless remains circular, its radius first increases with the depth from the surface of the stack and then decreases. In contrast, here we show that the symmetry of the deformed area breaks down when instead of a smooth elastomeric layer, one with topographical patterns is used in the stack. The metallic foil deforms through a polygonal area. The size and shape of the polygonal area vary with the flexibility of foil, geometry and dimension of the patterns and the intensity of the impact. For example, for one elastomeric layer decorated with pillars arranged in a square array, the damaged area turns rectangular to hexagonal and then to octagonal with increasing severity of impact, very much similar to polygonal wetting and spreading by a liquid on a patterned substrate.     

LIBS based spectroscopic analysis and antidiabetic evaluation of a polyherbal formulation

Although plants have long been a major source of medicine, there is renewed interest in studying the phytochemistry and use of herbal formulations. This paper reports spectroscopic analysis using Laser Induced Breakdown Spectroscopy (LIBS) of a polyherbal formulation, whose antidiabetic activity has also been demonstrated on rat models. LIBS analysis revealed the presence of elements such as Na, K, Mg, Ca, H, O and N. The antidiabetic study showed that amongst the four doses studied (50, 100, 150 and 200 mg/kg bw), the dose of 150 mg/kg bw registered the maximum fall in Blood Glucose Level (BGL) in both normal and diabetic (sub and mild) rats in the Glucose Tolerance Test (GTT) study—normal rats (22 %), sub-diabetic (36.6 %) and mild-diabetic (39 %). The dose of 150 mg/kg also showed the maximum fall of 23.7 % and 22 % in BGL during fasting BGL and GTT studies of normal rats, respectively. The formulation also showed significant antioxidant activity assessed using in vitro assays. The study validates for the first time the therapeutic use of an antidiabetic polyherbal formulation.     

Peanut proteins: Applications,ailments and possible remediation

Peanut is an annually grown plant and the chiefly cultivated species is Arachis hypogaea L. Mainly three types of proteins, arachin, conarachin I and conarachin II are present in peanut. It is an important and cheap source of protein. It can also cause allergic reactions in human beings. The peanut protein contains two components, Ara h 1 and Ara h 2 which are mainly responsible to cause allergy. Different remedial measures have been proposed to fight with the allergenic property of peanut proteins such as treatment with peroxidase, phytic acid, active charcoal, and various enzymes to minimize allergenic effect. Improper storage of peanuts causes growth of a fungal organism that releases aflatoxin, which is a carcinogen to mammals. Use of aluminosilicate clay, gamma irradiation, ozonation methods have been discussed for aflatoxin decontaminated from peanut. In this critical review, we have given an overview of the different extraction procedures of the peanut proteins and pointed out the methodologies to minimize allergenic actions and detoxification of the aflatoxin contamination in peanut.     

Mean lifetime calculations of quantum well structures: a rigorousanalysis

A matrix method that is applicable to an arbitrary potential variation represented by a set of linear functions such as multiple quantum well structures in the presence of a static electric field is described. An analytical expression for the mean lifetime of the quasi-bound state of a single quantum well in the presence of a static electric field is obtained     

Electrolysis of black liquor for hydrogen production: Some initial findings

Electrolysis of black liquor, an effluent from paper industry, was carried out and compared with alkaline water electrolysis. Energy efficiency in terms of HHV of hydrogen was found in the range of 84–97% whereas under similar conditions alkaline water electrolysis could not give more than 66% efficiency. Hydrogen evolution in black liquor electrolysis was possible even at an inter electrode potential of 1.17 V but in alkaline water electrolysis there was no hydrogen production below an inter electrode potential of 1.31 V. In addition to this, alkali lignin, amounting to 28–46 mg/mg of hydrogen produced, was separated at anode during black liquor electrolysis, which, on account of its good calorific value, has the potential of significantly improving the overall energy efficiency of the process.     

Planar optical waveguides with arbitrary index profile: an accuratemethod of analysis

We present here an improvement of the existing modified Airy function (MAF) method. The results of our study show that the improvement gives extremely accurate propagation constants and also the modal fields for planar waveguides with arbitrary index profile     

Synthesis of satellite footprint patterns from rectangular planar array antenna by using swarm‐based optimization algorithms

A pattern synthesis method based on Firefly Algorithm (FA) and Artificial Bee Colony (ABC) optimization has been presented to generate satellite footprint patterns from a rectangular planar array of isotropic antennas by modifying the amplitude, phase, and the state of the array elements. Three cases comprising three different footprints of rectangular, square, and circular boundary are generated from the same array by using two different swarm‐based optimization algorithms FA and ABC. Both the algorithms, following the proposed procedures are able to generate the three different footprint patterns while maintaining a satisfactory lower peak side lobe level and ripple. A comparative analysis has been carried out between FA, ABC, and Genetic Algorithm (GA) for the presented problem in terms of fitness value for the three different cases. The superiority of FA and ABC over GA has been established in terms of finding better solutions for all the three cases of the proposed problem. Copyright © 2013 John Wiley & Sons, Ltd.     

Calculated fiber attenuation: a general method yielding stationaryvalues

A method of calculating the attenuation constant of an optical fiber under very general but weakly guiding conditions is derived. The method, based on Galerkin's formalism, allows a nonuniform and complex refractive-index profile. The real and imaginary parts of the refractive index are allowed to vary independently and arbitrarily as a function of radius. The result is the predicted complex propagation constant. The results are inherently stationary