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This paper deals with the study of natural convection cooling of a discrete heater array in Cu-EG-water nanofluid filled rectangular enclosure. A 3 × 3 array of non-protruding heat sources is embedded on one of the vertical walls of the enclosure while the top horizontal and opposite vertical walls are assumed to be isothermally cold. The remaining portions in which the heaters are mounted and all other walls are insulated. The above setup is modeled into a system of partial differential equations which are solved numerically using finite volume method based on the Semi-Implicit Method for Pressure Linked Equation (SIMPLE) algorithm and power law scheme. The wide range of parameters for computation are the aspect ratio of the enclosure, the mixture proportion of Ethylene glycol-water, the solid volume fraction of the nanoparticle along with two different thermal conductivity models. It is observed that the proper choice of the computation parameters and thermal conductivity models could be able to maximize the heat transfer rate from the heater array. Also, the results obtained in this study will provide new guidelines in the field of electronic equipment cooling.

Aim:The aim of this study is to assess the effect of sodium hypochlorite and sterilization on the cyclic fatigue resistance of two reciprocating nickel-titanium files using a rotary and a reciprocating motor.Materials and Methods:Totally, 160 Reciproc and Wave One files were tested. The eighty files of the same brand were assigned into four groups (n = 20). These four groups were further divided into two subgroups, 1a and 1b, 2a and 2b, 3a and 3b, 4a and 4b consisting of ten files in each group. 2.5% NaOCl for 5 min, 2.5% NaOCl for 5 min + 1 cycle of autoclave sterilization, 2.5% NaOCl for 5 min + 5 cycles of autoclave sterilization, no sterilization (control). Groups 1a, 2a, 3a, and 4a were subjected to 30° and Groups 1b, 2b, 3b, and 4b were subjected to 60° canal curvature.Results:Intergroup comparison reveals that there is an increase in cyclic fatigue resistance from the first cycle to the fifth cycle of autoclave which is statistically significant.Conclusion:Reciproc and Wave One showed reduced cyclic fatigue resistance on immersion in NaOCl for 5 min. Multiple autoclaving cycles significantly increased the cyclic fatigue resistance of Reciproc file system in both the curvatures. There was a decrease in cyclic fatigue resistance for Wave One after multiple autoclaving at 60° curvature which was statistically significant.

Technologies that can contribute to sustainable environment and enhance economic feasibility have been gaining importance all over the world. The researchers have taken advantage of locally available materials and renewable sources in order to accomplish sustainable and economic construction activities. Many research works have been carried out in the field of ground improvement towards developing techniques that causes minimum impact on the environment. Some of the conventional materials that have been used in the past for embankment stabilization are lime, cement, fly ash, silica fumes, GGBS etc. Enzymatic treatment of ground is one of the emerging multi-disciplinary solutions that targets environment sustainability through stabilization using bio-enzymes. In this method bio-enzymes, which is obtained from vegetable extracts, are used for improving the mechanical characteristics of the natural weak soil. In the current work, a comparative study has been performed for the analysis of the different techniques/materials used for improvement of embankment/sub grade resting on expansive soil. The expansive/problematic soil is spread across a large part of central and western India and poses challenges to engineers due to its high compressibility properties. The improvement in the compressive strength characteristics of expansive soils when stabilized using materials like lime, rice husk ash, stone dust, fibre and bio-enzyme are being compared and studied in this work. On comparison it is observed when the stabilizing agent is pozzolanic in nature, curing period plays a crucial role as far as improvement factor is concerned.

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