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Main features of the present analysis is to investigate the MHD non-linear mixed convection flow of Carreau nanofluid. Flow is due to stretching sheet with thermal and solutal convective conditions. Intention in present analysis is to develop a model for nanomaterial. The non-linear ordinary differential systems are obtained. Homotopy algorithm leads to solutions development. Velocity, temperature, nanoparticles concentration, surface drag force, and heat and mass transfer rate are displayed and argued. It is revealed that qualitative behaviors of velocity and layer thickness are reverse for material and magnetic parameters. Temperature field and heat transfer rate are similar observation for thermal Biot numbers. Moreover qualitative behaviors of nanoparticles concentration and mass transfer rate are reverse for larger Brownian motion. [ABSTRACT FROM AUTHOR]

An analysis is introduced to investigate the salient features of nonlinear convective flow of thixotropic fluid in the version of Cattaneo-Christov heat flux theory. The stagnation point flow is present. The flow phenomenon is by an impermeable stretching sheet. The energy expression is modeled through the theory of Cattaneo-Christov heat flux. Characteristics of heat transfer phenomenon are described within the frame of variable thermal conductivity. Suitable variables reduced to the nonlinear partial differential expressions to the ordinary differential expressions. Series solutions of resulting systems are acquired within the frame of homotopy theory. Convergence analysis is achieved and suitable values are determined by capturing the so-called ℏ−curves. Graphical results for velocity and temperature are displayed and argued for sundry physical variables. Expression of skin friction coefficient is calculated through numerical values. Higher values of mixed convection parameter, Prandtl number, and thermal relaxation time lead to decay the temperature and layer thickness. [ABSTRACT FROM AUTHOR]

Geology of parent rock controls strongly the soil properties which in turn effect the generation and transportation of radon from its point of production to the surface of earth’s crust. Indoor radon concentrations mainly depend upon uranium and thorium content beneath the earth surface and diffusion of radon from rock and soil fractures, stoma and fissures. This paper presents the results of a survey of indoor radon concentrations in Neelum Valley District. CR-39 detectors were installed in 210 houses covering the entire study area. The detectors were retrieved after exposing to indoor radon for a period of 90 days and then etched in 6 M NaOH at 80°C for 16 h. The observed track densities were converted into the indoor radon concentrations using calibration factor of 2.7 tracks cm−2·h−1 per kBq·m−3. Mean annual effective doses were calculated for each measured value of radon concentration using UNSCEAR 2000 model. Effects of geology, fissures, crevice and cracks on radon levels have also been discussed. Results obtained from this study have been compared with radon concentration action levels given by the World Health Organisation and US Environmental Protection Agency and UK Health Protection Agency. [ABSTRACT FROM AUTHOR]