
Kinetics study on the phenol oxidation by catalytic wet air oxidation (CWAO) using CuO.NiO/Al2O3 as heterogeneous catalyst is presented. 4 g/l phenol solution of pH 7.3 was oxidized in a trickle bed reactor with gas flow rate of 80% stochiometric excess (S.E).. In order to verify the proposed kinetics, a series of CWAO experimental tests were done at two temperatures (140 and 160° C), oxygen partial pressures (9 and 12 bar), and weight hourly space velocity (WHSV) (1, 1.5, 2, 2.5, and 3 h-1). According to Power Law, the reaction orders are found to be approximately 1 and 0.5 with respect to phenol concentration and oxygen solubility, respectively. These values favorably compare with those cited in the literature for intrinsic kinetics,
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All central air conditioning systems contain piping system with various components, sizes, material, and layouts. If such systems in operating mode, the flow in piping system and its component such as valves can produce severe vibration due to some flow phenomenon’s. In this research, experimental measurements and numerical simulation are used to study the flow-induced vibration in valves. Computational fluid dynamics (CFD) concepts are included with one-way and two-way fluid-structure interaction concepts by using finite element software Package (ANSYS 14.57). Detection analysis is performed on flow characteristics under operation conditions and relations with structural vibration. Most of
... Show MorePhytomedicine refers to the use of naturally derived products to cure and mitigate human conditions. Natural products have the advantages of causing minimum side effects, being biocompatible, available, and economical, with a wide array of biological activities. Reports have described the use of natural products with antimicrobial and anti-inflammatory properties to treat oral conditions and promote wound healing. Moringa oleifera, known as the “drumstick” or “horseradish” tree, is believed to have medicinal properties regarding a range of medical conditions, though there is limited information on its use in oral medicine. This narrative review focuses on the use of Moringa extracts in the management of oral conditions, incl
... Show MoreIn this paper, the Monte Carlo N-Particle extended computer code (MCNP) were used to design a model of the European Sodium-cooled Fast Reactor. The multiplication factor, conversion factor, delayed neutrons fraction, doppler constant, control rod worth, sodium void worth, masses for major heavy nuclei, radial and axial power distribution at high burnup are studied. The results show that the reactor breeds fissile isotopes with a conversion ratio of 0.994 at fuel burnup 70 (GWd/T), and minor actinides are buildup inside the reactor core. The study aims to check the efficiency of the model on the calculation of the neutronic parameters of the core at high burnup.
In this paper a stirred-bed performed of the copper catalyzed synthesis of ethylchlorosilanes from silicon and ethyl chloride was described. A Si-catalyst mixture prepared by reaction of CuCl and Si was employed. The compositions of products were mainly ethyltrichlorosilane, diethyldichlorosilane, and ethyldichlorosilane and mainly depended on the extent of Cu in the mixture and the reaction temperature. A promoting effect on the extent of adsorption was observed on the addition of certain additives. The kinetic data revealed the direct depended of the reaction rate on C2H5Cl pressure.
In this paper, the problem of developing turbulent flow in rectangular duct is investigated by obtaining numerical results of the velocity profiles in duct by using large eddy simulation model in two dimensions with different Reynolds numbers, filter equations and mesh sizes. Reynolds numbers range from (11,000) to (110,000) for velocities (1 m/sec) to (50 m/sec) with (56×56), (76×76) and (96×96) mesh sizes with different filter equations. The numerical results of the large eddy simulation model are compared with k-ε model and analytic velocity distribution and validated with experimental data of other researcher. The large eddy simulation model has a good agreement with experimental data for high Reynolds number with the first, seco
... Show MoreIn this paper a dynamic behavior and control of a jacketed continuous stirred tank reactor (CSTR) is developed using different control strategies, conventional feedback control (PI and PID), and neural network (NARMA-L2, and NN Predictive) control. The dynamic model for CSTR process is described by a first order lag system with dead time.
The optimum tuning of control parameters are found by two different methods; Frequency Analysis Curve method (Bode diagram) and Process Reaction Curve using the mean of Square Error (MSE) method. It is found that the Process Reaction Curve method is better than the Frequency Analysis Curve method and PID feedback controller is better than PI feedback controller.
The results s
... Show MoreA vector in a separable infinite dimensional Hilbert space is called disk-cyclic for bounded operator if the orbit α : 0, α∈;|∝| 1is dense in. The useful tool used to discover codisk-cyclic operation is called the disk-cyclic Criterion. In this paper we will show that some equivalent conditions of the
Abstract Background: The lifestyle of an individual significantly influences health-promoting behaviors. The World Health Organization defines health promotion as a mechanism enabling people to increase control over and improve their health. This study aimed to evaluate the health promoting lifestyle profile of medical staff working in primary health care centers of Al-Rusafa, Baghdad.
OBJECTIVE: To determine the preferred specialties of graduated medical doctors working in Basra, and determine the factors behind their preferences. METHODS: The study was conducted in 38 primary health care centres and seven hospitals in Basra from January-June 2014. A cross-sectional study was adopted with the use of a self-administered questionnaire form. Two hundred ninety six graduated doctors were agreed to participate. Chisquare test and logistic regression were used to test the association between deciding a future speciality and influencing factors. RESULTS: The most preferred specialties were radiology and ultrasound, gynaecology and obstetrics, surgery, internal medicine, dermatology and paediatrics. Clinical specialties were sta
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