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Kinetic Modeling of Light Naphtha Hydroisomerization in an Industrial Universal Oil Products Penex^(TM)Unit

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Energy Engineering 2023年第6期120卷 1371-1386页

作者： ramzy s.hamied Zaidoon M.shakor Anfal H.sadeiq Adnan A.Abdul Razak Ammar T.Khadim Department of Petroleum Technology University of TechnologyBaghdadIraq Department of Chemical Engineering University of TechnologyBaghdadIraq Midland Refineries Company Al-Dura RefineryBaghdadIraq

Recently,the isomerization of light naphtha has been increasingly significant in assisting refiners in meeting sternness specifications for *** process provides refiners with the advantage of reducing sulfur,olefin,and benzene in the gasoline basin without significantly victimizing the *** mathematical modeling of a chemical reaction is a critical tool due to it can used to optimize the experimental data to estimate the optimum operating conditions for industrial *** paper describes light naphtha isomerization reactions over a Pt/Al_(2)O_(3)-Cl catalyst at the Al-Dura Oil Refinery(Baghdad,Iraq)using a newly developed universal mathematical *** proposed kinetic model involves 117 isomerization reactions and 90 cracking reactions to describe 52 real components graded from methane to n-octane.A Genetic Algorithm stochastic optimization technique applied in MATLAB R2020a software was employed to estimate the optimal set of kinetic *** calculated activation energies for hydrocracking reactions was found to be higher than the other reactions because of hydrocracking reactions occur at higher range of *** benchmarking between the experimental and theoretical results for all 117 data sets,the mean absolute error was obtained to be 0.00360 for all 52 ***,a positive effect of increasing reaction temperatures was recognized on enhancing the research octane number(RON).

关键词： Light naphtha hydroisomerization reactions kinetics mathematical modelling

Tribological evaluation of thermoplastic polyurethane-based bearing materials under water lubrication:Effect of load,sliding speed,and temperature

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Friction 2024年第8期12卷 1801-1815页

作者： shaoli JIANG Janet ssWONG Debashis PUHAN Tian YUAN Xiuqin BAI Chengqing YUAN state Key Laboratory of Maritime Technology and safety Wuhan University of TechnologyWuhan 430063China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Yusuf hamied Department of Chemistry University of CambridgeLensfield RoadCambridge CB21EWUK

Polymers are widely used in bearing *** the case of water-lubricated stern tube bearings,thermoplastic polyurethane(TPU)-based composites are used due to their excellent wear resistance,corrosion resistance,and tunable mechanical *** tribological performance,however,depends on operating *** this work,TPU was blended with carbon fiber,graphene platelet,and ultra-high molecular weight polyethylene(UHMWPE).Friction tests of TPU based-composites against copper countersurface were carried out in water to mimic the actual operating conditions of the *** of the resulting contacts were in the boundary lubrication regime,in which friction was attributed to both contact mechanics of asperities as well as water *** results show that the viscoelasticity of TPU has a considerable impact on its tribological *** lubrication at 50°C promotes the softening of polymer surface material during sliding,resulting in higher fluctuation in the coefficient of friction and wear *** is attributed to the reduced thermomechanical *** addition,schallamach waviness is observed on worn *** tribological properties of TPU are significantly improved by the inclusion of carbon fiber,graphene platelet,and *** formation of graphene transfer-layers and UHMWPE transfer film reduces friction and wear loss,while the inclusion of carbon fiber enhances wear resistance due to improved mechanical properties and load bearing capacity.

关键词： friction thermoplastic polyurethane(TPU) water-lubricated bearings graphene platelet carbon fibers ultra-high molecular weight polyethylene(UHMWPE)

Effect of si-addition as a grain refiner on microstructure and properties of Ti-6Al-4V Alloy

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Transactions of Nonferrous Metals society of China 2013年第7期23卷 1863-1874页

作者： Khaled M.IBRAHIM Abdel hamied HUssEIN Mohamed ABDELKAWY Central Metallurgical R&D Institute CMRDICairoEgypt Cairo University GizaEgypt

Two different Ti alloys were cast in a graphite mould using vacuum induction skull melting furnace. The first alloy was Ti-6Al-4V and the second was Ti-6Al-4V 0.5si. silicon as a grain refiner was added into Ti-6Al-4V alloy, and the effects of si-addition on the microstructure and properties of the as-cast and swaged alloys were investigated. Hot swaging at 900 °C was performed on the cast samples and then two different thermal treatments were applied. The first treatment was done by heating the swaged samples at 1050 °C to produce fine lamella structure, while the second treatment was carried out at 1050 °C and then decreased the temperature to 800 °C for getting coarse lamella structure. An addition of 0.5% si to Ti-6Al-4V alloy decreased the grain size of the as-cast sample from 627 to 337 μm. There was an increase in ultimate tensile strength of about 25 MPa for the as-cast Ti-6Al-4V 0.5si alloy compared to Ti-6Al-4V due to the refinement effect caused by si addition. A maximum ultimate tensile strength of 1380 MPa and a minimum corrosion rate （1.35×10 6 mm/a in Hank’s solution and 5.78×10 4 mm/a in NaCl solution） were reported for the heat treated fine lamella structure of Ti-6Al-4V 0.5si alloy. The wear rate was decreased to about 50% by adding 0.5% si at low sliding speeds and to about 73% at high sliding speeds.

关键词： Ti-6Al-4V alloy silicon casting grain refinement heat treatment wear

Iraqi Personality in Light of Ali Al-Wardi＇s Works： A Critical Review

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sociology study 2017年第1期7卷 1-6页

作者： hamied G. M. Al-Hashimi International Colleges of Islamic sciences UK

This paper sheds light on the Iraqi personality in light of writings of the Iraqi eminent sociologist Dr. Ali Al-Wardi and gives a critical review to his main findings and hypotheses. Al-Wardi was the main person who established the first department of sociology in Iraq and the spiritual father or the real father of sociology in the country. He wrote prestigious works about the Iraqi society including some hypotheses focusing on the Iraqi personality, such as the dual personality and social dissonance. These findings and hypotheses are not above criticism of course. The method we depend on here is the content analysis methodology. The paper consists of seven parts; part one is the introduction which includes a short glimpse on the subject and A1-Wardi＇s methodology. Part two deals with Al-Wardi and studying Iraqi personality. Part three, discusses the dual personality, and part four, the social dissonance. Part five, exposures tackling the problem where Al-Wardi suggests some points. Part six deals with the discussion. Finally, there is a conclusion under the part seven.

关键词： lraq personality Ali Al-Wardi dual personality social inconsistency tribal values

Ligamentotaxis versus Open Reduction and Internal Fixation for Distal Radius Intra-Articular Fractures

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Open Journal of Orthopedics 2017年第1期7卷 21-31页

作者： Mahmoud Abdel-Ghany Tohamy Goudah Tohamy Wael M. shaaban Abdel-hamied A. Atallah Tharwat M. Abdel-Rahman Orthopedic and Trauma surgery Al-Azhar University Cairo Egypt

Objectives: This study compared the clinical and radiological outcomes of two different methods for the treatment of distal radial intra-articular fractures. Patients and Methods: Forty-six patients with distal radius intra-arti-cular fractures were divided into two groups. Group I included 24 patients with type C fracture treated by external fixator augmented by percutaneous K-wires. Group II included 22 patients with type C fracture treated by volar locked distal radial plate augmented by K-wires. Two patients had complex injuries necessitating double plating (sandwich). All patients were evaluated clinically by Mayo Wrist score and radiologically by sarmiento’s radiological score. Results: Both groups reported good personal satisfaction according to Mayo Wrist score, and the results were not statistically different between the two groups. In Group I, 19 patients (79.2%) had excellent radiological outcome and five patients (20.9%) had good radiological outcome according to sarmiento’s radiological score. In Group II, 20 patients (90.9%) had excellent outcome, and two (9.1%) had good radiological outcome;there was no or insignificant deformity. Conclusions: Complex distal radial fractures can be treated either by external fixation (ligamentotaxis) or by locked pre-contoured plating. The clinical outcome of plating and external fixator in our study did not show any statistically significant difference. The radiological outcome had no correlation with the clinical outcome.

关键词： Distal Radial Fracture Complex Fracture of Distal Radius External Fixator Locked Volar Plate