Antioxidant activity represents one of the important features of phenolic acids, such as hydroxyderivatives of cinnamic acid. However, in the case of cis-cinnamic acid derivatives, corresponding thermochemistry data can be still considered scarce. This work is focused on the two most relevant mechanisms of primary antioxidant action in gas-phase, n...

By Monika Biela, Peter Poliak, Andrea Kleinová, Vladimír Lukeš, Erik Klein

This study is focused on the joint effects of thermal radiation and magnetic field on an unsteady flow of natural convective, electrically conducting fluid past an irregular vertical channel in the presence of viscous dissipation. The magnetic field is applied normal to the channel. The coupled ordinary differential equations (ODE) are obtained usi...

By T. L. Oyekunle, S. A. Agunbiade

Ascorbyl radical is often used as a biomarker of oxidative stress in human organism. It is a product of the antioxidant activity of ascorbic acid and it is not expected to react further with biologically important molecules. For the first time, the reactivity of catecholamines and their precursors was investigated theoretically and experimentally t...

By Dušan Dimić, Đura Nakarada, Miloš Mojović, Jasmina Dimitrić Marković

In this paper, the governing equations of continuity and momentum subjected to suitable boundary conditions have been solved numerically to investigate the fluid flow in stirred vessel of two-bladed impeller. The numerical simulations have been carried out in three-dimensions for laminar flow. The studied fluid was considered Newtonian and incompre...

By Houssem Laidoudi

Erosion caused by solid particles in curve pipes is one of the major concerns in the oil and gas industries. Small solid particles flow with a carrier liquid fluid and impact the inner wall of the piping, valves, and other equipment. These components face a high risk of solid particle erosion due to the constant collision, which may result in equip...

By Mohammad Sheikh Mamoo, Ataallah Soltani Goharrizi, Bahador Abolpour

This paper presents the simulation of the multi-cylinder 4-stroke cycle spark-ignition engine using a commercial simulation tool, AVL BOOST and Fire. Various models were examined to select the appropriate models that would best serve to analyze the main components of the exhaust systems: the plenum chamber, the muffler and the exhaust manifold bran...

By Barhm Mohamad, Andrei Zelentsov

This article discusses a method for calculating the dynamic characteristics of thin-walled viscoelastic composite pipes made by continuous winding under the influence of internal hydrodynamic pressures. The solution is based on an approximate energy method based on the instant theory of shells and the second-order Lagrange equation. Initial technol...

By Muhsin Kh. Muhsin Kh., Ismail I. Safarov, Mirziyod Mirsaidov

The performance of a magnetic fluid based short bearing is examined with the effect of viscosity variation. The pressure temperature relation of Tipei (1962) concerning viscosity variation is adopted here. The Neuringer-Rosensweig’s model has been considered for the magnetic fluid flow. The related modified Reynolds type equation is solved fo...

By Jimit R. Patel, Gunamani Deheri

The flow on the upper surface of NACA 0015 airfoil is subject to an adverse pressure gradient when the incidence increases. This leads to the boundary layer separation which causes losses in the aerodynamic performances. Control using Vortex Generators (VGs) is a simple passive mean used to delay or eliminate the flow separation from the wall. The ...

By Hocine Tebbiche, Mohammed Saîd Boutoudj

A theoretical investigation on the flow of nonlinear magnetohydrodynamic (MHD), laminar, viscous, incompressible boundary layer fluid with thermal radiative heat transfer and variable properties past a stretching plate was carried out. The liquid is taken to be gray, absorbing, emitting but with non-scattering medium. The main nonlinear equations g...

By Akindele M. Okedoye, Sulyman O. Salawu