Falleh R. Al-Solamy

Radiative hydromagnetic flow of jeffrey nanofluid by an exponentially stretching sheet.

Two-dimensional hydromagnetic flow of an incompressible Jeffrey nanofluid over an exponentially stretching surface is examined in the present article. Heat and mass transfer analysis is performed in the presence of thermal radiation, viscous dissipation, and Brownian motion and thermophoresis effects. Mathematical modelling of considered flow problem is developed under boundary layer and Rosseland’s approximations. The governing nonlinear partial differential equations are converted into ordinary differential equations via transformations. Solution expressions of velocity, temperature and concentration are presented in the series forms. Impacts of physical parameters on the dimensionless temperature and concentration are shown and discussed. Skin-friction coefficients are analyzed numerically. A comparison in a limiting sense is provided to validate the present series solutions.

Comparison Functions and Fixed Point Results in Partial Metric Spaces

The aim of this article is to clearly formulate various possible assumptions for a comparison function in contractive conditions and to deduce respective (common) fixed point results in partial metric spaces. Since standard metric spaces are special cases, these results also apply for them. We will show by examples that there exist situations when a partial metric result can be applied, while the standard metric one cannot.

Radiative Three-Dimensional Flow with Chemical Reaction

Abstract We discuss the three-dimensional boundary layer flow of Maxwell nanofluid in the present article. The flow is caused due to bidirectional stretching surface. An applied magnetic field is taken into account. Heat and mass transfer characteristics are considered in the presence of thermal radiation, Brownian motion, thermophoresis and chemical reaction effects. Mathematical modelling is made under a low magnetic Reynolds number and Rosseland’s approximation. Expressions of series solutions for velocities, temperature and concentration are developed. Impacts of influential parameters on the temperature and concentration are sketched and examined. Numerical values of local Nusselt and Sherwood numbers are computed and analyzed. We found that an increase in thermophoresis and Brownian motion parameters enhanced the temperature field and thermal boundary layer thickness. The concentration field reduced gradually when we enhance the values of Lewis number and chemical reaction parameter. The values of local Nusselt number are higher for a larger radiation parameter.

Influence of Carbon Black Structure and Specific Surface Area on the Mechanical and Dielectric Properties of Filled Rubber Composites

Natural rubber based composites have been prepared using various amounts of two fillers: conventional Corax N220 carbon black or electrically conductive carbon black Printex XE-2B which has a very high specific surface area. The composites have been studied by dynamic mechanical thermal analysis, dielectric thermal analysis and SEM. It has been established that all vulcanizates investigated are in the glass state in the C to C interval. The storage modulus increases with the increasing filler content in the C to

On the prospects of conducting polyaniline/natural rubber composites for electromagnetic shielding effectiveness applications

Conductive polymer composites are at the forefront of composites science research because of the huge number of applications that have been developed around their interesting and unique properties. The present article is focused on the fabrication of natural rubber/polyaniline (NR/PANI) compounds for electromagnetic wave shielding applications at microwave frequency. Their microstructures were examined by means of scanning electron microscopy and thermogravimetric analyses. The as-fabricated NR/PANI composite was mechanically characterized to investigate the effect of dispersion of PANI on NR matrix composite. The dielectric spectroscopy, absorption loss, and reflection loss of NR/PANI composite in the frequency range from 1 to 12 GHz have been performed. The total electromagnetic interference shielding effectiveness by absorption and reflection loss depends on PANI content in the composite. Results show that the NR/PANI composite represents a new class of conducting lightweight material that makes the NR/PANI with good electromagnetic shielding effectiveness that is suitable for use in industrial application such as electronic conducting composite in polymer package and for radar absorbing materials.

On the existence of a new class of semi-Riemannian manifolds

AbstractThe present paper deals with the existence of a new class of semi-Riemannian manifolds which are weakly generalized recurrent, pseudo quasi-Einstein and fulfill the condition R·R=Q(S,R). For this purpose, we presented a metric, computed its curvature properties, and finally checked various geometric structures arising out from the different curvatures by means of their covariant derivatives of first and second order.MCS53C15; 53C25; 53C35

Semi-Slant Warped Product Submanifolds of a Kenmotsu Manifold

We study semi-slant warped product submanifolds of a Kenmotsu manifold. We obtain a characterization for warped product submanifolds in terms of warping function and shape operator and finally proved an inequality for squared norm of second fundamental form.

Semi-invariant warped product submanifolds of almost contact manifolds

In this article, we have obtained necessary and sufficient conditions in terms of canonical structure F on a semi-invariant submanifold of an almost contact manifold under which the submanifold reduced to semi-invariant warped product submanifold. Moreover, we have proved an inequality for squared norm of second fundamental form and finally, an estimate for the second fundamental form of a semi-invariant warped product submanifold in a generalized Sasakian space form is obtained, which extend the results of Chen, Al-Luhaibi et al., and Hesigawa and Mihai in a more general setting.2000 Mathematics Subject Classification: 53C25; 53C40; 53C42; 53D15.

Warped Product Submanifolds of Riemannian Product Manifolds

We study warped product of the type and , where , , and are proper slant, invariant, and anti-invariant submanifolds, respectively, and we prove some basic results and finally obtain some inequalities for squared norm of second fundamental form.

Pressure Sensors Based on Polyvinyl Chloride/Graphite/Nickel Nanocomposites

The composites based on polyvinyl chloride polymer matrix filled with foliated graphite/nickel nanoparticles with remarkable and reliable pressure sensitivity was successfully fabricated. The microstructure of the nanocomposites was characterized by means of scanning electron microscopy. The effect of graphite/nickel content on the thermal stability of polyvinyl chloride/graphite/nickel nanocomposites was studied via thermal gravimetric analysis. Thermal conductivity and glass transition temperature were evaluated as a function of graphite/nickel content also. The resistivity dependence on applied pressure was tested. It was found that the polyvinyl chloride/graphite/nickel nanocomposites display a high sensitivity to pressure with good repeatability. The nanocomposites obtained may be used as pressure sensors.