Thermal performance of closed wet cooling tower has been investigated experimentally and theoretically
in this work. The theoretical model based on heat and mass transfer equations and heat and mass transfer balance equations which are established for steady state case. A new small indirect cooling tower was used for conducting experiments. The cooling capacity of cooling tower is 1 kW for an inlet water temperature of 38oC, a water mass velocity 2.3 kg/m2.s and an air wet bulb temperature of 26oC. This study investigates the relationship between saturation efficiency, cooling capacity and coefficient of performance of closed wet cooling tower versus different operating parameters such wet-bulb temperature, variable air-spray water fl

Cerium oxide CeO2, or ceria, has gained increasing interest owing to its excellent catalytic applications. Under the framework of density functional theory (DFT), this contribution demonstrates the effect that introducing the element nickel (Ni) into the ceria lattice has on its electronic, structural, and optical characteristics. Electronic density of states (DOSs) analysis shows that Ni integration leads to a shrinkage of Ce 4f states and improvement of Ni 3d states in the bottom of the conduction band. Furthermore, the calculated optical absorption spectra of an Ni-doped CeO2 system shifts towards longer visible light and infrared regions. Results indicate that Ni-doping a CeO2 system would result in a decrease of the band gap. Finally,

In this study, aromatic polyamide reverse osmosis membranes were used to remove zinc ions from electroplating wastewater. Influence of different operating conditions such as time, zinc concentration and pressure on reverse osmosis process efficiency was studied. The experimental results showed, concentration of zinc in permeate increase with increases of time from 0 to 70 min, and flux of water through membrane decline with time. While, the concentrations of zinc in permeate increase with the increase in feed zinc concentration (10–300 mg/l), flux decrease with the increment of feed concentration. The raise of pressure from 1 to 4 bar, the zinc concentration decreases and the flux increase. The highest recovery percentage was found is 54.

A new ligand N-(methylcarbamothioyl) acetamide (AMP) was synthesized by reaction of acetyl chloride with adenine. The ligand was characterized by FT-IR, NMR spectra and the elemental analysis. The transition metal complexes of this ligand where synthesize and characterized by UV-Visible spectra, FT-IR, magnetic suscepility, conductively measurement. The general formula [M(AMP)2Cl2], where M+2 = (Mn, Co, Ni, Cu, Zn, Cd, Hg).

A hydraulic platform was manufactured to serve palm trees and to enhance palm tree services, with a height of 12 meters, by the General Company for Hydraulic Industries, one of the Ministry of Industry's formations. This platform was tested in the field after being manufactured according to a randomized complete block design using split-split plots with three factors. The first factor represented the shape of the orchard land, with two levels (flat land and uneven land), serving as the main plots. The second factor had three levels representing palm tree heights (4, 8, and 12 meters), which served as the sub-plots. The third factor was the palm tree services, represented at three levels (pruning, pollination, and harvesting), with each trea

Investigation of mesomorphic properties of new 1,3,4-thiadiazolines (which are synthesised via many steps in Scheme 1) was carried out in this study. These compounds are designed to have a heterocyclic unit, a carboxylate linkage group and a polar ether chain at the end of the molecule adjacent to the benzene ring, which enhance the dipolar interactions forces (varied from one to eight carbons) to investigate the association properties of their phases. The structure of the target compounds and the intermediates were confirmed by 1H NMR, 13C NMR, mass and FTIR spectral techniques. Polarised microscopic studies revealed that all the compounds in the series exhibited enantiotropic liquid crystalline properties. This was further confirmed using

The psychological burnout is considered one of dangerous phenomenon’s which appeared in the 70s of the 20th century and suffered by most of the society classes. It is a term which the wide uses and various meaning like emotional, mental, and physical exhaustion and chronic weak exhaustion. The presented research aims t identify the psychological burnout as for the Kindergarten teacher and the differences significance according to the variations (Kindergarten type: private or govern mental). The research sample contains 400 female teachers divided to 170 governmental Kindergarten teachers and 230 private Kindergarten teachers. The researcher prepared a measurement method to measure the psychological burnout for those teachers after

The fluctuation and expansion ratios have been studied for cylindrical gas-solid fluidized columns by using air as fluidizing medium and Paracetamol as the bed material. The variables were the column diameter (0.0762, 0.15, and 0.18 m), static bed height (0.05, 0.07, and 0.09 m), and air velocity to several times of minimum fluidization velocity. The results showed that both the fluctuation and expansion ratios had a direct relation with air velocity and an inverse one with column diameter and static bed height. A good agreement was between the experimental results and the calculated values by using the correlation equations from the literature.