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Hydrodynamics, Mass and Heat Transfer in Reactive Distillation
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      The ethyl acetate synthesis via heterogeneous reactive distillation is studied experimentally using ethanol and acetic acid. Three types of cation exchanging resins were used as catalysts: Zerolit 225, Zerolit 226 and Ambylite 400. Experiments were carried out in two units of the same dimensions. Each unit consisted of three sections: rectifying, reactive and stripping sections of heights (60+25+20) cm respectively and 2.5cm column diameter. The first unit (column-A-) was a fractionation type and the second unit (column-B-) was packed column. The packing type was hollow glass cylinders with 10 mm height, and 4, 5 mm inner and outer diameter respectively.

      The experiments were carried out by using two operation modes. The semi-batch and continuous operation mode. In the first part of present investigation, the semi-batch mode was used to evaluate the catalyst type and to evaluate the performance of reactive distillation unit configuration (Fractionation and packed column). Results show that, the column-B- gave higher conversion rates than column-A-. This is attributed to the high surface area available for liquid vapour contact in packed type column, which leads to increasing mass transfer rates.  On the other hand, Ambylite 400 catalyst showed higher activity for esterification reaction than other two types of catalysts.

      The second part of work continued with column -B- only. It is well known that, the esterification process is regarded one of exothermic reactions. Therefore, the monitoring of the temperature distribution along column axial for all three types of catalysts showed that the temperature distribution was essentially the same due to steady state operation in continuous operation mode. On the other hand, the effect of reflux ratio on temperature distribution was clearly noted, that is as the reflux ratio increased the temperature distribution along the column was reduced for each type of catalysts.

      On the other hand, the experimental results point that, as a reflux ratio increases the conversion rates of acetic acid is increased too because such increasing is related to high mass transfer rates between  vapour and liquid along reactive distillation column.

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Publication Date
Sat Dec 30 2017
Journal Name
Al-khwarizmi Engineering Journal
Buckling Analysis of Unidirectional Polymer Matrix Composite Plates
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This study deals with the estimation of critical load of unidirectional polymer matrix composite plates by using experimental and finite element techniques at different fiber angles and fiber volume fraction of the composite plate.

            Buckling analysis illustrated that the critical load decreases in nonlinear relationship with the increase of the fiber angle and that it increases with the increase of the fiber volume fraction.

            The results show that the maximum value of the critical load is (629.54 N/m) at (q = 0°) and (Vf = 40 %) for the finite element method, while the minimum val

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Publication Date
Fri Mar 05 2021
Journal Name
Materials
Optimum Placement of Heating Tubes in a Multi-Tube Latent Heat Thermal Energy Storage
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Utilizing phase change materials in thermal energy storage systems is commonly considered as an alternative solution for the effective use of energy. This study presents numerical simulations of the charging process for a multitube latent heat thermal energy storage system. A thermal energy storage model, consisting of five tubes of heat transfer fluids, was investigated using Rubitherm phase change material (RT35) as the. The locations of the tubes were optimized by applying the Taguchi method. The thermal behavior of the unit was evaluated by considering the liquid fraction graphs, streamlines, and isotherm contours. The numerical model was first verified compared with existed experimental data from the literature. The outcomes re

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Publication Date
Mon Nov 01 2021
Journal Name
Energies
Solidification Enhancement in a Triple-Tube Latent Heat Energy Storage System Using Twisted Fins
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This work evaluates the influence of combining twisted fins in a triple-tube heat exchanger utilised for latent heat thermal energy storage (LHTES) in three-dimensional numerical simulation and comparing the outcome with the cases of the straight fins and no fins. The phase change material (PCM) is in the annulus between the inner and the outer tube, these tubes include a cold fluid that flows in the counter current path, to solidify the PCM and release the heat storage energy. The performance of the unit was assessed based on the liquid fraction and temperature profiles as well as solidification and the energy storage rate. This study aims to find suitable and efficient fins number and the optimum values of the Re and the inlet tem

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Publication Date
Sun Jan 13 2019
Journal Name
Iraqi Journal Of Physics
Energy transfer process between two laser compounds coumarin 334 & rhodamine 590
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In the current research the absorption and fluorescence spectrum
of Coumarin (334) and Rhodamine (590) in ethanol solvent at
different concentration (10-3, 10-4, 10-5) M had been studied. The
absorption intensity of these dyes increases as the Concentration
increase in addition to that the spectrum was shifted towards the
longer wavelength (red shift). The energy transfer process has been
investigated after achievement this condition. The fluorescence peak
intensity of donor molecule was decrease and its bandwidth will
increases on the contrary of the acceptor molecule its intensity
increase gradually and its bandwidth decreases as the acceptor
concentration increase.

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Publication Date
Thu Dec 01 2022
Journal Name
Al-khwarizmi Engineering Journal
Comparative Transfer Learning Models for End-to-End Self-Driving Car
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Self-driving automobiles are prominent in science and technology, which affect social and economic development. Deep learning (DL) is the most common area of study in artificial intelligence (AI). In recent years, deep learning-based solutions have been presented in the field of self-driving cars and have achieved outstanding results. Different studies investigated a variety of significant technologies for autonomous vehicles, including car navigation systems, path planning, environmental perception, as well as car control. End-to-end learning control directly converts sensory data into control commands in autonomous driving. This research aims to identify the most accurate pre-trained Deep Neural Network (DNN) for predicting the steerin

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Publication Date
Thu Dec 01 2016
Journal Name
Iraqi Journal Of Physics, 2016
Energy transfer process between two laser compounds coumarin 334 & rhodamine 590
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Abstract: In the current research the absorption and fluorescence spectrum of Coumarin (334) and Rhodamine (590) in ethanol solvent at different concentration (10-3, 10-4, 10-5) M had been studied. The absorption intensity of these dyes increases as the Concentration increase in addition to that the spectrum was shifted towards the longer wavelength (red shift). The energy transfer process has been investigated after achievement this condition. The fluorescence peak intensity of donor molecule was decrease and its bandwidth will increases on the contrary of the acceptor molecule its intensity increase gradually and its bandwidth decreases as the acceptor concentration increase.

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Publication Date
Sat Aug 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Probability Concepts of Transfer Load to the Foundation of Container Structure
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This paper presents stochastic analysis using the perturbation method to model the structure of a container to verify the distributions of probability of maximum and minimum axial forces reactions in piles. The proposed simulation of a container port terminal under 11 scenarios of load combinations was presented. The probability distributions for live loads are assigned according to the input parameters of simulation data. Part of the load itself is implicitly combined such as vertical live load which includes the weight of equipment and containers and wind load. The structural model was simulated in the software STAAD Pro., while the statistical analyses were performed with MATLAB. The results demonstrated that, the most significant extern

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Scopus (5)
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Publication Date
Fri Jan 01 2021
Journal Name
دراسات قانونية
The Legal Nature of the Build-Operate- transfer-Ownership Contract (B.O.T.)
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The legal nature of the Build-Operate-Transfer-Ownership Contract (B.O.T) The Build, Operate, and Transfer of Ownership Contract (BOT) has emerged as the most successful and safest method for involving the private sector in public sector services. The major infrastructure projects that are built through the BOT contract are no longer financed by the state and its budget, but the private sector has played a major role in financing These projects, especially developing countries that need to establish infrastructure or modernize their existing infrastructure, especially in the areas of transport, communications, services, electricity, water ..... and other public utilities.

Publication Date
Wed Nov 28 2018
Journal Name
Al-khwarizmi Engineering Journal
Effect of Using Combined Square Nozzle & winglet with Helical Tape on Thermal Characteristics in Tube Heat Exchanger
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Influence of combined square nozzle with helical tape inserted in a constant heat flux tube on heat transfer enhancement for turbulent airflow for Reynolds number ranging from 7000 to 14500 were investigated experimentally. Three different pitch ratios for square nozzle (PR = 5.8, 7.7 and 11.6) according to three different numbers of square nozzle (N = 3, 4 and 5) and constant pitch ratios for helical tape were used. The results observed that the Nusselt number and friction factor for combination with winglets were found to be up to 33.8 % and 21.4 %, respectively higher than nozzle alone for pitch ratio PR=5.8. The maximum value of thermal performance for using combination with winglets was about 1.351 for pitch ratio= 5.8. Nusselt numb

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Publication Date
Fri Jun 01 2012
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Bank credit and the most important ratios related to the granting: An analytical study of the company advanced Petrokimot Saudi Arabia
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  Bank credit is extremely important, as the generated revenues by a main focus of any bank earnings no matter how many and varied sources of revenue other, and without losing the bank and the main role function as an intermediary in financial economics . But at the faltering customers in payment of loans .   Therefore , uses a method of financial analysis using ratios as one of the important tools to measure the clients ability to pay , in spite of the need for the Bank analyzed the trend in this regard is focused on three main areas ( liquidity, profitability, and borrowing ) and can be to add another field is the possibility to cover fixed charges of the profits generated.   Finally I would like to emphas

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