Measurements at 2.4, 3.4, 5.2, 28 and 60 GHz for Device-to-Device Wireless Communications

Wireless Personal Communications - Wireless communication networks with increased demand for higher speed in data transfer have paved way for device-to-device (D2D) wireless communications. This...     

Marine yeasts-a review

Yeasts are ubiquitous in their distribution and populations mainly depend on the type and concentration of organic materials. The distribution of species, as well as their numbers and metabolic characteristics were found to be governed by existing environmental conditions. Marine yeasts were first discovered from the Atlantic Ocean and following this discovery, yeasts were isolated from different sources, viz. seawater, marine deposits, seaweeds, fish, marine mammals and sea birds. Near-shore environments are usually inhabited by tens to thousands of cells per litre of water, whereas low organic surface to deep-sea oceanic regions contain 10 or fewer cells/litre. Aerobic forms are found more in clean waters and fermentative forms in polluted waters. Yeasts are more abundant in silty muds than in sandy sediments. The isolation frequency of yeasts fell as the depth of the sampling site is increased. Major genera isolated in this study were Candida, Cryptococcus, Debaryomyces and Rhodotorula. For biomass estimation ergosterol method was used. Classification and identification of yeasts were performed using different criteria, i.e. morphology, sexual reproduction and physiological/biochemical characteristics. Fatty acid profiling or molecular sequencing of the IGS and ITS regions and 28S gene rDNA ensured accurate identification.     

Insights from principal component analysis applied to Py-GCMS study of Indian coals and their solvent extracted clean coal products

The present work aims at studying five Indian coals and their solvent extracted clean coal products using Py-GCMS analysis and correlating the characterization ...     

Loading Rate-Dependent Mechanical Properties of Bulk Two-Phase Nanocrystalline Al-Pb Alloys Studied by Nanoindentation

Bulk samples (dia. = 20 mm) of various nanocrystalline (nc) Al-Pb alloys with Pb content varying from 1 to 4 at. pct are fabricated using spark plasma sintering of ball-milled powders. Al matrix in Al-2 at. pct Pb alloy had a grain size of 53 nm, and Pb particle size was 6 ± 2 nm. High angle annular dark-field image obtained in STEM mode of TEM indicates the presence of Pb along the nc Al grain boundaries as well as dispersion of smaller Pb particles in the intra-granular regions. Hardness studies are carried out using microindentation and nanoindentation with load varying over three orders of magnitude (100 ? 0.1 g). Microindentation yielded slightly smaller hardness values in comparison to nanoindentation possibly because of indentation size effect. Nevertheless both microindentation and nanoindentation resulted in the same trend of hardness for various nc Al-Pb alloys. Hardness of Al-Pb alloys increased with increase in Pb content up to the additions of 2 at. pct Pb, beyond that the hardness is decreased for higher Pb additions of 3 and 4 pct. The initial hardening behavior is explained based on the Orowan particle strengthening. Strain rate sensitivity (SRS) has increased with increase in Pb content reaching a value of 0.1 for Al-4 at. pct Pb alloy. Activation volumes measured are between 2.84 and 6.15 b ³. Higher SRS and lower activation volume suggest that grain boundary-mediated processes are controlling the deformation characteristics.     

Lipase immobilized on nanostructured cerium oxide thin film coated on transparent conducting oxide electrode for butyrin sensing

Nanostructured cerium oxide (CeO₂) thin films were deposited on transparent conducting oxide (TCO) substrate using spray pyrolysis technique with cerium nitrate salt, Ce(NO₃)₃·6H₂O as precursor. Fluorine doped cadmium oxide (CdO:F) thin film prepared using spray pyrolysis technique acts as the TCO film and hence the bare electrode. The structural, morphological and elemental characterizations of the films were carried out using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray analysis (EDX) respectively. The diffraction peak positions in XRD confirmed the formation of highly crystalline ceria with cubic structure and FE-SEM images showed uniform adherent films with granular morphology. The band gaps of CeO₂ and TCO were found to be 3.2 eV and 2.6 eV respectively. Lipase enzyme was physisorbed on the surface of CeO₂/TCO film to form the lipase/nano-CeO₂/TCO bioelectrode. Sensing studies were carried out using cyclic voltammetry and amperometry, with lipase/nano-CeO₂/TCO as working electrode and tributyrin as substrate. The mediator-free biosensor with nanointerface exhibited excellent linearity (0.33–1.98 mM) with a lowest detection limit of 2 μM with sharp response time of 5 s and a shelf life of about 6 weeks.     

FOC-MOP: Fuzzy Optimal Clustering Based Multi-Objective Parameter Route Selection for Energy Efficiency

Wireless Personal Communications - Wireless sensor networks are emerging and involved in a wide range of applications. Improving energy efficiency is a significant task in WSNs. Energy consumption...     

Effect of SWCNTs and MWCNTs Maxwell MHD nanofluid flow between two stretchable rotating disks under convective boundary conditions

The aim of the current analysis is to investigate heat and mass transfer characteristics of single and multi‐walled water‐based carbon nanotubes Maxwell nanofluid flow between continuously rotating stretchable disks under the sway of chemical reaction and radiation. Boundary conditions of the convective type of temperature are employed at both lower and upper rotating disks in the preparation. Similarity variables are employed to transform the governing partial differential equations into the nonlinear ordinary differential equations. The computational finite element method is applied to solve this nonlinear system of equations along with boundary conditions. The sway of different admissible parameters on the profiles of concentration, temperature, and velocity are inspected and revealed through graphs. Furthermore, the numerical solutions for rates of temperature, concentration, and rates of velocity are depicted in tabular form. It is revealed that temperature sketches deteriorate with augmented values of Deborah number at both upper and lower disks of single‐walled carbon nanotubes and multi‐walled carbon nanotubes with water‐based Maxwell nanofluids.     

Heat and mass transfer analysis of MWCNT‐kerosene nanofluid flow over a wedge with thermal radiation

A comparison between the unsteady and steady magnetohydrodynamics Tiwari‐Das model Williamson nanofluid flow through a wedge occupied by carbon nanotubes of multiwalled type nanoparticles and kerosene as base fluid is presented in this analysis. A suitable similarity variable technique is adopted to transmute the governing partial differential equations into a set of nonlinear ordinary differential equations (ODEs). To solve these ODEs together along with boundary conditions, we have utilized finite element analysis. The behavior of concentration, temperature, and velocity sketches for diverse values of the pertinent parameters is plotted through graphs. The impact on the above parameters on the rates of velocity, heat, and concentration is also evaluated and depicted through tables. It is noted that as the values of nanoparticle volume fraction parameter rises, the rates of temperature increase in both the unsteady and steady cases.