The purpose of this paper is to gain a good understanding about wake region behind the car body due to the aerodynamic effect when the air flows over the road vehicle during its movement. The main goal of this study is to discuss the effect of the geometry on the wake region and the aerodynamic drag coefficient. Results will be achieved by using two different shapes, which are the fastback and the notchback. The study will be implemented by the Computational Fluid Dynamic (CFD) by using STAR-CCM+^® software for the simulation. This study investigates the steady turbulent flow using k-epsilon turbulence model. The results obtained from the simulation show that the region of the air separation behind the vehicle

The fouling depositions of crude oil stream were studied theoretically in a shell and tube heat exchanger to investigate the effect of depositions on the heat transfer process. The employed heat exchanger was with steam flowing in the inner tubes and crude oil in the shell at different velocities and bulk temperatures. It is assumed that fouling occurs only on the heated stream side (crude oil). The analysis was carried out for turbulent flow heat transfer conditions with wide range of Reynolds number, bulk temperature and time. Many previously proposed models for fouling resistance were employed to estimate a new model for fouling rate. It is found that the fouling rate and consequently the heat transfer coefficient were affected by Rey

This study was conducted to examine the anatomical aspects of Carissa macrocarpa, of stem, leaf and leaf venation. The results obtaind showed that the tissue of the studied parts have important anatomical characteristics in terms of the shape of the cross-sectional of stem and vertical-sectional of leaves. The stem section appeared in circular and the midrib was crescent shape and the stomata appeared on the upper surface of the leaf only, Tetracytic in type. Druses crystals and Aleurone granules appeared on both surfaces of leaves. The venation type was Brochidodromous in which the secondary veins do not end at the edge of the leaf, and each secondary race is connected with the higher rac

The sol-gel preparation technique of transparent silica monoliths containing up to 0.5 M of samarium have been described. The sol-gel processing parameters are: acid catalyzed hydrolysis and controlled drying. The prepared monoliths are analyzed by X-ray diffraction, pycnometer measurements, Fourier transformation infrared spectroscopy and optical spectroscopy. The oscillator strengths of the Sm3+ ions in the silica monoliths are calculated. The results show a linear concentration dependence of some Sm3+ transitions in UV/Vis absorption spectra and formation of Sm3+ clusters inside the pores structure of silica monoliths at high Sm3+ concentration

The concept of intertextuality was one of the problems that occupied the attention of critics and critics in targeting the structure of textual intertextuality between texts and their overlap in the process of producing meaning. Until intertextuality became a stable term and it can be monitored in the structure of the theatrical text and determining the mechanisms of this intertextuality between texts through fields and classifications agreed upon by the most important critics who wrote and considered intertextuality. Perhaps our previous research (the approach of exposure in the epistemological hallway to intertextuality) was an attempt to interview a terminology, which the researcher intended to monitor, through the mechanisms of inter

Maxillofacial trauma in females is not widely reported. This study aimed to analyze the clinical characteristics and the patterns of maxillofacial injuries in females and to determine the differences in these patterns among different causes. This retrospective study analyzed several variables, including demographic, social, injury-related, and treatment-related variables, and compared these variables in relation to the main etiologies of maxillofacial trauma. The main etiologies of maxillofacial injuries involving females were assault, followed by road traffic accidents, and falls. There were significant differences in relation to the 3 etiologies in age groups (P= 0.002) and marital status (<

Density functional theory calculations are employed to investigate the impact of edifenphos molecule on the reactivity and electronic sensitivity of pure calcium oxide (CaO) nanocluster. The strong adsorption of edifenphos molecule on CaO nanocluster occurs by the sulfur head of the adsorbate, and the amount of the energy of this adsorption is around − 84.40 kcal/mol. The adsorption of edifenphos molecules results in a decrease in the values of Eg of CaO from 4.67 to 3.56 eV, as well as an increase in the electrical conductance. Moreover, the work function of CaO nanocluster is significantly affected, which changes the current of the field emission electron. Eventually, the recovery time is calculated around 99 ms at ambient temperature f

Abstract

In this work, the plasma parameters (electron temperature (T_e), electron density( n_e), plasma frequency (f_p) and Debye length (λ_D)) have been studied by using the spectrometer that collect the spectrum of Laser produce CdTe_(X):S_(1-X) plasma at X=0.5 with different energies. The results of electron temperature for CdTe range 0.758-0.768 eV also the electron density 3.648 10¹⁸ – 4.560 10¹⁸ cm^-3  have been measured under vacuum reaching 2.5 10^-2 mbar .Optical properties of CdTe:S were determined through the optical transmission method using ultraviolet visible spectrophotometer within the r