Scanning electron microscopy of Streptomyces without use of any chemical fixatives

A new, short, and quick method was developed for preparation of specimen for observing Actinomycetes of genus Streptomyces by scanning electron microscopy. The cultures were directly grown on stubs and coated with a film of gold without using any fixative and dehydrating procedures. Using this simple preparation procedure, surface of intact sporing structures of Streptomyces was observed over a range of magnifications. As the preparation procedure is so simple and rapid, this procedure could be most useful for the routine examination and identification of Streptomyces.     

An efficient algorithm for backbone construction in cognitive radio networks

Numerous research articles exist for backbone formation in wireless networks; however, they cannot be applied straightforward in cognitive radio network (CRN) due to its peculiar characteristics. Since virtual backbone has many advantages such as reduced routing overhead, dynamic maintenance, and fast convergence speed, we intend to propose a backbone formation protocol in CRN. In this paper, we propose a tree‐based backbone formation protocol along with its maintenance. Our protocol is based on non‐iterative approach, thus leading towards limited message overhead and faster convergence speed. The proposed algorithm first forms the tree by maintaining the parent‐child relationship, and second, the parent nodes are connected together to form the virtual backbone. In the end, we evaluate the performance our protocol through extensive simulations.     

Adsorptive removal of trinitrophenol using nano α-Fe2O3/reduced graphene oxide

Abstract

2,4,6-Trinitrophenol (TNP), an explosive utilized for artillery munitions, ends up polluting water and soil. This study targets the treatment of TNP contaminated water via adsorption technique. A comparative adsorption study using pristine rGO (reduced graphene oxide), α-Fe₂O₃/rGO, bare α-Fe₂O₃ and physical mixture of α-Fe₂O₃ & rGO has been carried to select the most suitable adsorbent. To understand the mechanism of adsorption of TNP on α-Fe₂O₃/rGO adsorption isotherms were applied on adsorption data. The adsorption kinetics followed pseudo second order kinetic model. The mechanism of adsorption changed significantly with change in pH. The maximum adsorption capacity was found to be 769.23?mg?·?g^?1. Regeneration studies indicated that the adsorbent can be used up to 3 times without significant decrease in adsorption efficiency. Magnetic nature of adsorbent allowed its easy segregation from the contaminant solution upon application of external magnetic field. To assess the adsorption efficacy of α-Fe₂O₃/rGO in real water under ambient condition, TNP was spiked in ground water samples collected from adjoining district that had high TDS (Total dissolved solids). The Langmuir adsorption capacity of 164.24?mg?·?g^?1 was attained with substantial decrease in TDS. Thus α-Fe₂O₃/rGO proves to be an efficient adsorbent for nitrophenols and can be used commercially for waste water treatment.     

Saponin-loaded SBA-15: release properties and cytotoxicity to Panc-I cancer cells

In this study, first time a nanoformulation, saponin-loaded SBA-15 has been developed for an improved and continuous release. The SBA-15 nanopowder was synthesized by a hydrothermal process. Saponin was introduced into the mesoporous channels of SBA-15 and its concentration in SBA-15 was measured by UV–visible spectrophotometry. The pristine SBA-15 and saponin-loaded SBA-15 were characterized by small-angle XRD, FESEM, HRTEM, TGA, FTIR. N₂ adsorption–desorption isotherms were used to measure the specific surface area and pore channel structure parameters of pristine and loaded SBA-15. Saponin release was studied in phosphate buffered saline (pH 7.4), which revealed that the release rate could be effectively controlled. The controlled drug release is highly desired for cancer treatment. The cytotoxicity of pristine and loaded SBA-15 was analyzed on Panc-I cancer cells. Both the pristine SBA-15 and saponin-loaded SBA-15 nanoparticles showed specific toxicity on the cancer cells. The preliminary results showed that saponin-loaded SBA-15 could be an effective therapeutic agent for Panc-I cancer cells.     

Clustering‐based resource discovery on Internet‐of‐Things

Resource discovery on Internet‐of‐Things paradigm is an eminent challenge due to data‐specific activities with respect to foraging and sense‐making loops. The prerequisite to deal with the challenge is to process and analyze the data that require resources to be indexed, ranked, and stored in an efficient manner. A novel clustering technique is proposed to resolve the specified challenge. The technique, namely, iterative k‐means clustering algorithm, targets concrete cluster formation using similarity coefficients of vector space model and performs efficient search against matching criteria with respect to complexity. It is simulated on MATLAB, and the obtained results are compared with fuzzy k‐means and fuzzy c‐means clustering algorithm with similarity coefficients of vector space model against exponential increase in the number of resources.     

Response of Multilayer Foundation System beneath Railway Track under Cyclic Loading

For an efficient and economical design of a railway track system, it is necessary to understand the behavior of each track component with special reference to ballast and subgrade, which play a pivotal role in distributing the large, cyclic wheel loads longitudinally, laterally, and vertically away from the wheel contact area on the rail surface to the underlying soil strata. This paper presents an analytical model of a track-ballast-subgrade system with different formation soils such as dense uniform sand, stiff clay, loose sand, and soft clay modeled by using a mass-spring dashpot system with two degrees of freedom. This represents the varying energy distribution through ballast and subgrade in the vertical direction. Results are presented in the form of time-displacement response profiles for both the ballast and subgrade layers. In addition, the magnification factors for displacements with variation in subgrade soils for cyclic loading frequencies are reported. It is observed that the results obtained from the present analysis follow the experimentally observed trends already available in the literature.     

All‐polymer electromechanical systems consisting of electrostrictive poly(vinylidene fluoride‐trifluoroethylene) and conductive polyaniline

The low elastic modulus and the ability to withstand high strain without failure make the conducting polymer attractive for a wide range of acoustic applications based on high‐strain electroactive polymers. In this article, we examine the electric and electromechanical performance of all‐polymer electromechanical systems, fabricated by painting conductive polyaniline (PANI) doped with camphor sulfonic acid (HCSA) on both sides of electrostrictive Poly(vinylidene fluoride‐trifluoroethylene) (P(VDF‐TrFE)) copolymer films, and compare them with those from the same copolymers with gold electrodes. The all‐polymer composite films are flexible, with strong coherent interfaces between the electrostrictive polymer layer and the conductive polymer layer. The electric performance such as dielectric properties and polarization hysteresis loops from P(VDF‐TrFE)/PANI film is nearly identical to those of P(VDF‐TrFE)/gold films in a wide temperature (from −50 to 120°C), and frequency range (from 1 Hz to 1 MHz). The all‐polymer systems also show a similar or even larger electric field induced strain response than that of films with electrodes under identical measurement conditions. The results demonstrate that the polyaniline/HCSA is good candidate material as the electrodes for electroactive polymers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 945–951, 2000     

Thermal performance analysis of small-sized solar parabolic trough collector using secondary reflectors

ABSTRACT

In this paper, theoretical analysis of receiver tube misalignment, the design of secondary reflector and experimental analysis of a small-sized solar parabolic trough collector (PTC) with and without secondary reflectors are represented. Experimental analysis of PTC has been done using a parabolic secondary reflector (PSR) and triangular secondary reflector (TSR) and compared with PTC without secondary reflector (WSR). The maximum outlet temperature of heat transfer fluid is observed as 49.2°C, 47.3°C and 44.2°C in the case of PSR, TSR and WSR conditions, respectively. The maximum thermal efficiency of 24.3%, 22.5% and 17.8% is observed in the case of PSR, TSR and WSR conditions, respectively. The circumferential temperature difference on the outer surface of the receiver tube is obtained more uniform in the case of PSR and TSR than WSR condition. This indicates that the use of a secondary reflector can improve the performance of a solar PTC system.     

Multi-objective optimization of electric-discharge machining process using controlled elitist NSGA-II

Parametric optimization of electric discharge machining (EDM) process is a multi-objective optimization task. In general, no single combination of input parameters can provide the best cutting speed and the best surface finish simultaneously. Genetic algorithm has been proven as one of the most popular multi-objective optimization techniques for the parametric optimization of EDM process. In this work, controlled elitist non-dominated sorting genetic algorithm has been used to optimize the process. Experiments have been carried out on die-sinking EDM by taking Inconel 718 as work piece and copper as tool electrode. Artificial neural network (ANN) with back propagation algorithm has been used to model EDM process. ANN has been trained with the experimental data set. Controlled elitist non-dominated sorting genetic algorithm has been employed in the trained network and a set of pareto-optimal solutions is obtained.