A compact ACS-fed dual-band monopole antenna for LTE,WLAN/WiMAX and public safety applications

In this paper, a compact asymmetric coplanar strip (ACS)-fed printed monopole antenna for dual frequency operation is presented. The proposed antenna is composed of an ACS-fed monopole structure and two semi circle shaped radiating branches, which occupies a very small size of 13.4 × 22.7 mm² including the ground plane. By properly selecting the length and position of these branches, two desired operating bands can be achieved and tuned independently. The simulated and measured return loss results shows that the proposed antenna can be used for long term evolution 2500 (2500–2690 MHz), WLAN 5.2 GHz (5.15–5.35 GHz)/5.8 GHz (5.725–5.825 GHz), WiMAX 5.5 GHz (5.28–5.85 GHz) and 4.9 GHz (4.94–4.99 GHz) public safety applications. The omnidirectional and bidirectional radiation pattern characteristics in H-plane and E-plane of the proposed antenna along with acceptable peak gain make the best suitable candidate for the above intended applications.     

Morphological, structural, and functional properties of maranta (Maranta arundinacea L) starch

Starch isolated from maranta (Maranta arundinacea) tuber and studied for its various physicochemical characteristics. The amylose content of the starch was 24.8%. SEM showed that the granules were small indented and spherical. Maranta starch granule size has a range of 2.92–6.42 μm, (mean of 4.84 μm), length/degree of 1.20, and roundness of 0.73. Maranta starch has a gelatinization temperature of 74.8°C, peak viscosity of 498 BU, and cold paste viscosity of 669 BU. It also possessed higher freeze-thaw stability. Dynamic rheological properties of maranta starch, measured using parallel plate geometry showed increased storage modulus (G’) values, while loss modulus (G″) values were decreased with increasing frequency values (0–100 Hz). The low gelatinization temperature and high freeze thaw stability of starch indicates its potential for application as a thickener in food industries.     

A compact uniplanar ACS fed multi band low cost printed antenna for modern 2.4/3.5/5 GHz applications

Microsystem Technologies - A uniplanar compact triple operating band asymmetric coplanar strip (ACS) fed printed antenna loaded with multiple L-shaped branches and the asymmetric rectangular ground...     

X-ray diffraction spectroscopic and thermal studies on 1,3,5-trinitro-hexahydropyrimidine (TNP)

TNP, a heterocyclic nitramine containing a C NO₂ functionality, has been studied as regards the kinetics and mechanism of thermal decomposition, morphology and the gaseous products evolved therof, using thermogravimetry (TG), differential thermal analysis (DTA), infrared spectroscopy (IR), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and hot stage microscopy. The elementary cell parameters obtained form the XRD pattern are: a = 18.818 ± 0.005 Å, b = 18.818 ± 0.005 Å and c = 4.867 ± 0.005 Å. The crystal belongs to the hexagonal system with c/a ratio = 0.259. IR spectra of TNP have also been recorded and the bands assigned. Kinetics of thermolysis has been followed both by isothermal TG and IR. The best linearity with a correlation coefficient of 0.986 was obtained for the three-dimensional diffusion controlled Jander-equation. Kinetic parameters were evaluated from the induction period as well as from isothermal TG. Activation energy was found to be 202.05 kJ/mol and log A(in s-¹) 22.78 from TG and 181.133 kJ/mol and log A (in s¹) 20.97 from IR, respectively. The corresponding values were 171.17 kJ/mol and log A (in s-¹) 21.20 from the induction period data. The effect of a series of additives incorporated to the extent of 5 %, on the initial thermolysis of TNP, has also been studied. Evolved gas analysis by IR showed that CO₂, NO₂, NO and N₂O are produced in larger amounts than CO and HCN. The cleavage of the N N bond appears to be the primary step in the thermolysis of TNP.     

Enzyme-Assisted Process for Production of Superior Quality Vanilla Extracts from Green Vanilla Pods Using Tea Leaf Enzymes

Vanilla planifolia Andrews is a perennial tropical vine and is an orchid grown for its pleasant flavor. There is an increasing trend world over for using natural flavors. Vanilla being an important food flavoring ingredient, the demand for natural vanilla extract is increasing. Hence, the aim of the present study was to prepare vanilla extract from green beans without going through the elaborate and time-consuming conventional curing process. Vanilla beans after size reduction were mixed in a suitable proportion with tea leaf enzyme extract (TLEE) and incubated to facilitate action of enzymes on vanilla flavor precursors. The beans mix was squeezed, and the filtrate was treated with ethanol to extract the vanilla flavor. TLEE-treated extracts had higher vanillin content (4.2%) compared to Viscozyme extract (2.4%). Also, it had higher intensity of vanilla flavor, sweet, and floral notes. Further, electronic nose analysis confirmed the discrimination between extracts. It was concluded that the use of TLEE is very much useful to obtain higher yield of vanilla extract and superior quality vanilla flavor, which avoids the traditional laborious and time-consuming curing process.     

Multielement analysis in cereals and pulses by k0 instrumental neutron activation analysis

The concentrations of some elements in a few varieties of cereals and pulses are determined by Instrumental Neutron Activation Analysis using a single comparator method (k0-standardised NAA method). A total of 15 elements are measured. The method was validated by analysing the Standard Reference Material (SRM-1571) of NIST; the results are within +/-10% of the reported values for the majority of the elements. The measured concentrations of major and minor elements are analysed in terms of the average intake of mineral content and the role of these elements in terms of the nutritional value.     

Free vibration and stability behaviour of uniform beams and columns on nonlinear elastic foundation

Free vibration and stability behaviour of uniform beams and columns on nonlinear elastic foundation are evaluated using a finite element formulation. Numerical results are presented for various end boundary conditions with varying foundation parameters.