Tariq Javed

Bio: Tariq Javed is an academic researcher from International Islamic University, Islamabad. The author has contributed to research in topics: Nusselt number & Heat transfer. The author has an hindex of 20, co-authored 139 publications receiving 1440 citations.

Photocatalytic degradation of disperse dye Violet-26 using TiO2 and ZnO nanomaterials and process variable optimization

Abstract: The degradation of disperse V-26 in solution using UV; UV/H2O2, UV/H2O2/TiO2 and UV/H2O2/ZnO were investigated. The impacts of various key parameters i.e. initial pH, concentration of hydrogen peroxide (H2O2) dose and the dye concentration effect on degradation were studied. The maximum degradation of 93 % was optimized using UV/H2O2/TiO2 at pH 3 in 60 min. Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC MS) were applied to check the products obtained after complete degradation. The removal of peaks of certain groups present in dye molecule assured the maximum degradation of dispersive V-26. In biological treatment, cytotoxicity reduction and Ames test were used to check the toxicity level of products. Certain water parameters i.e. dissolved oxygen (DO), chemical oxygen demand (COD) and biological oxygen demand (BOD) were also performed to ensure the maximum degradation of DV-26. DO was increased up to 82 %. The COD and BOD were reduced considerably owing to the treatment of disperse dye Violet 26 at optimum settings of process variables. The degradation of disperse dye V-26 with UV/H2O2/ZnO was 90.1 % which increased up to 93 % with the alternative photo-catalyst UV/H2O2/TiO2.

ZnO, MgO and FeO adsorption efficiencies for direct sky Blue dye: equilibrium, kinetics and thermodynamics studies

Abstract: Adsorption is one of the promising techniques for the remediation of wastewater and it also offers advantages such as low cost, availability of the adsorbent and ease in operation. The wastewater treatment using smart materials gained much attention and the present investigation evaluated the adsorption efficiencies of ZnO, MgO and FeO for the removal of Direct Sky Blue (DSB) dye. The adsorption affecting parameters, i.e., effect of adsorbent dose, pH, concentration of dye, temperature and contact time were studied in association with dye adsorption. The effect of electrolytes and surfactants was also studied on dye adsorption. The dye adsorption data was analysed using various kinetics parameters, isotherms and thermodynamics models. The maximum adsorption capacities of MgO, FeO and ZnO were recorded to be 46.7, 42.9 and 40.9 mg/g, respectively at the pH 2, adsorbent dose 0.05 g, contact time 75 min, 40 °C and 70 mg/L initial concentration of the dye. The dye adsorption onto MgO followed a Langmuir isotherm, while ZnO followed Temkin isotherm. Langmuir and Temkin isotherms were satisfactory in the case of FeO. Pseudo second order best explained the dye adsorption kinetics. The thermodynamics studies revealed non-spontaneous adsorption of DSB dye onto ZnO, MgO and FeO. In view of promising efficiency, the ZnO, MgO and FeO have potential to apply for dyes adsorption from textile wastewater.

Iron oxide (Fe2O3) prepared via green route and adsorption efficiency evaluation for an anionic dye: kinetics, isotherms and thermodynamics studies

Abstract: Textile sector is one of the major industries responsible for water pollution and the remediation of dyes is necessary to safe guard the water resources. Adsorption using nanoadsorbents have been emerged as one of viable techniques to eliminate the dyes from wastewater. Iron oxide was prepared via green route using Fan palm (F.P), Dombeya wallichii (D.W) and Pyrus comminis (P.C) as a reducing, capping and stabilizing agents. The adsorption of anionic dye using nanoadsorbents was studied and pH, adsorbent dose, contact time, temperature and concentration of dye were optimized. The maximum dye adsorption was achieved at pH 3, 0.01 g/50 mL adsorbent dose, 200 mg/L initial concentration at 65 °C. Thermodynamic study revealed that the adsorption on to nanoadsorbents was an endothermic process. Langmuir model and pseudo-second-order fitted well to the dye adsorption data. The presence of detergents and surfactants affected the dye adsorption on to nanoadsorbents. Efficient desorption was attained using 0.5 N sodium hydroxide. Results revealed that iron oxide prepared via green route is an efficient adsorbent for the removal of anionic dye and could possibly be used for the remediation of textile effluents.

Analysis of heat transfer due to stretching cylinder with partial slip and prescribed heat flux: A Chebyshev Spectral Newton Iterative Scheme

Abstract: This study is dedicated to analyze the combined effects of partial slip and prescribed surface heat flux when the fluid is moving due to stretching cylinder. A very moderate and powerful technique Chebyshev Spectral Newton Iterative Scheme is used to determine the solution of the present mathematical model. Involved physical parameters, namely the slip parameter, Casson fluid parameter, curvature parameter and Prandtl number are utilized to control the fluid moments and temperature distribution. The results show that the fluid velocity and the skin friction coefficient on the stretching cylinder are strongly influenced by the slip parameter. It is further analyzed that hydrodynamic boundary layer decreases and thermal boundary layer increases with the slip parameter. Influence of Casson fluid parameter on temperature profile provides the opposite behavior as compared to the slip parameter. The comparison of numerical values of skin friction coefficient and the local Nusselt number is made with the results available in the literature. The accuracy and convergence of Chebyshev Spectral Newton Iterative Scheme is compared with finite difference scheme (Keller box method) through tables. The CPU time is calculated for both schemes. It is observed that CSNIS is efficient, less time consuming, stable and rapid convergent.

Numerical simulation of MHD flow of micropolar fluid inside a porous inclined cavity with uniform and non-uniform heated bottom wall

Abstract: Buoyancy-driven, incompressible, two-dimensional flow of a micropolar fluid inside an inclined porous cavity in the presence of magnetic field is investigated. The nonlinear partial differential eq...

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Introduction to the Finite Element Method

Abstract: This chapter introduces the finite element method (FEM) as a tool for solution of classical electromagnetic problems. Although we discuss the main points in the application of the finite element method to electromagnetic design, including formulation and implementation, those who seek deeper understanding of the finite element method should consult some of the works listed in the bibliography section.