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Nabavi S.V.,Islamic Azad University at Khomain | Beirami M.K.,Islamic Azad University at Estahban | Chamani M.R.,Isfahan University of Technology | Sterling M.,University of Birmingham
Flow Measurement and Instrumentation | Year: 2011

This paper presents a theoretical model based on the free vortex theorem that is capable of predicting the pressure head distribution at the brink of free overfalls in open channels. This approach is coupled with the momentum equations to obtain the end-depth-ratio (EDR) from which the discharge can be estimated. In order to illustrate its flexibility, the theory is successfully applied to flat-based circular and U-shaped channels. Using previous experimental data, the proposed method is validated. © 2010 Elsevier Ltd.


Hashemihezaveh M.,Islamic Azad University at Khomain | Mahanpoor K.,Islamic Azad University at Khomain | Soudbar D.,Islamic Azad University at Khomain
Petroleum Science and Technology | Year: 2015

In this research, a new phosphite ligand (tri-2-naphthylphosphite (L)) was synthesized using standard Schlenk technique under N2 atmosphere. Then an RhH(CO)3L complex was formed with this ligand in during the hydroformylation reaction. Initial rate and selectivity (linear aldehyde/branch aldehyde [l/b] ratio) of rhodium complex catalyst was studied for hydroformylation of 1-dodecene at temperature of 60-90°C, a pressure of 2-6 MP with different H2/CO ratio, and various initial concentrations of 1-dodecene. Effect of ligand/metal ratio (L/Rh) and catalyst initial concentration was studied in selectivity and rate of hydroformylation reaction. The maximum amount of (l/b) with the most appropriate reaction rate was obtained in temperature = 70°C, Pressure = 3MP (with H2/CO = 1.5/1.5), initial 1-dodecene concentration = 1.56 mol/L, (L/Rh) = 6. The results show that the reaction rate for production of linear aldehyde increases when the concentration of catalyst was increased. Copyright © 2015 Taylor & Francis Group, LLC.


Bahrami H.,Islamic Azad University at Khomain | Ghareh S.,Payame Noor University
Electronic Journal of Geotechnical Engineering | Year: 2016

In recent years, the application of high structures with deep foundations which were implemented as piles has been dramatically increasing in the developing urban regions. On the other hand, the construction of massive civil infrastructures made the subject of the need for excavation in the vicinity of exploited buildings as an ignorable issue. Therefore, this study tends to investigate accurate prediction of changes in lateral load capacity of pile group adjacent to urban excavations. For this purpose, application of the finite element software of PLAXIS and using the plane strain theory with 15 node elements for modeling the environment. Toward this, changes were studied in the lateral load capacity of pile group. Computation of the lateral load capacity of pile group is based on load-displacement diagrams. For this purpose and based on valid methods, horizontal displacement as a criteria for limitation of lateral displacement of pile group is considered by ten percent. The results of the present study show negligible effects of excavation on the lateral loading capacity of pile group over distances extended than width of an excavation computed from the edge of the excavation. It is to be noted that the results indicate significant effect of elasticity modulus changes in connection with changes in loading capacity changes of the pile group. © 2016 ejge.


Islamic Azad University at Khomain | Entity website


Islamic Azad University at Khomain | Entity website

: 38815/171: 7-46337801 (086) : 46337820 (086)


Islamic Azad University at Khomain | Entity website


Islamic Azad University at Khomain | Entity website


Islamic Azad University at Khomain | Entity website

1378 . 1379 ( ) 250 ...


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Islamic Azad University at Khomain | Entity website

: 38815/171: 7-46337801 (086) : 46337820 (086)

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