Computational study of three-dimensional laminar and turbulent flows around electronic chip (heat source) located on a printed circuit board are presented. Computational field involves the solution of elliptic partial differential equations for conservation of mass, momentum, energy, turbulent energy, and its dissipation rate in finite volume form. The k-ε turbulent model was used with the wall function concept near the walls to treat of turbulence effects. The SIMPLE algorithm was selected in this work. The chip is cooled by an external flow of air. The goals of this investigation are to investigate the heat transfer phenomena of electronic chip located in enclosure and how we arrive to optimum level for cooling of this chip. These par

Kaolin ceramic compacts sintered at various temperatures are investigated to correlate their microstructure with their acoustic parameters.  Pulse  velocity  ,  attenuation  coefficient,  and  quality factor values are ducts from ultrasonic attenuation measurements, moreover, the dynamical mechanics parameters( Young and shear modules) exhibited an explicit relationship with the acoustic quality factor.inturn  are  related  to  the  microstructure  which  is  heavily affected by the sintering mechanism.

A hydrophilic interaction chromatography has been investigated to separate 2-deoxycytidine chosen for nucleoside. A small molecule with specific features for human serum samples was 2-deoxycytidine tested. 2-deoxycytidine has been applied to self-made stationary hydrophilic phases (ZIC1 and ZIC5). The deoxycytidine (dCD) retention was investigated with varying concentrations of sodium acetate buffer, acetonitrile%, and pH. The results confirmed the hydrophilicity of 2-deoxycytidine. The exchanger retention mechanism was studied taking into account 2-deoxycytidine used for describing the interaction of hydrophilic and cation. For both ZIC1 and ZIC5 exchangers, we described and discussed the influence of chromatographic conditions (co

Abstract

The current research aims to identify the negotiation behavior of administrative teachers, as well as to identify the significance of the differences in negotiation behavior according to the variables (gender, scientific title, length of service). After confirming the psychometric characteristics of (20) items, the researchers applied the scale to (400) male and female administrative teaching staff who were randomly selected from the University of Baghdad for the academic year 2021/2022. The results showed the following the research sample has a negotiating behavior. There are no statistically significant differences between gender, scientific title, and length of service in the means of negotiating beha

    The motion of fast deuterons in most dense plasma focus devices  ( DPF ) , may be characterized that it has a complex nature in its paths and this phenomena by describing a through gyrating motion with arbitrary changes in magnitude and direction .  In this research , we focused on the  understanding the theoretical concepts which  depend deeply on the experimental results to explain the deuteron motions in the pinch region , and then to use the fundamental physical formulas that are deeply related to the explanation of this motion to prepare a suitable model for calculating the vertical and radial components for deuteron velocity by improving the  Rung – Kutta  Method

The present study aims to explore determinants of entrepreneurial behavior from perspective of social theory. It is based on model notions of (Tyler & Blader, 2003) which have focused on studying role of positively personal and social identity in motivating employees to practicing desired behavior which serves the organization in which they work. Based on these notions and previous literature, study model were built. This model explains the relationship between status judgments (perceived internal respect and perceived external prestige)  and entrepreneurial behavior. It includes three main hypotheses. The first and second hypothesis are concerning the relationship between status judgmen

In this study, epoxy was used as a matrix for composite materials, with E-glass fiber, jute and PVC fiber which was woven roving fiber, as reinforcement with volume fraction (Vf= 30%). There are two of prepared types of epoxy non reinforced, epoxy reinforced with E-glass, jute and PVC fibers including study of mechanical tests (Impact test, Bending test) different temperature and thermal conductivity and calculating the temperatures coefficient at different temperature. Results show that elastic modulus at rate values decrease to the increase of temperature and the impact strength, impact energy and thermal conductivity increase with increase temperature.

Polymer electrolytes were prepared using the solution cast technology. Under some conditions, the electrolyte content of polymers was analyzed in constant percent of PVA/PVP (50:50), ethylene carbonate (EC), and propylene carbonate (PC) (1:1) with different proportions of potassium iodide (KI) (10, 20, 30, 40, 50 wt%) and iodine (I₂) = 10 wt% of salt. Fourier Transmission Infrared (FTIR) studies confirmed the complex formation of polymer blends. Electrical conductivity was calculated with an impedance analyzer in the frequency range 50 Hz–1MHz and in the temperature range 293–343 K. The highest electrical conductivity value of 5.3 × 10^-3 (S/cm) was observed for electrolytes with 50 wt% KI concentration at room