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Article
A Deactivation Correlation for Platinum Y-Zeolite in n-Hexane Isomerization

Author: Haiyam Mohammed A. Al-Raheem
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 8 Pages: 1451-1462
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The objective of the present work is to realize the kinetic modeling regardingdeactivation of Pt-HY zeolite and monitor the isomerization reaction of n-hexane. Thecatalyst has been prepared with o.4% Pt and evaluated during the isomerization reactionof n-hexane. Based on the results of catalytic investigation, a kinetic model was proposedto deactivate the catalyst by coke formation. The present method provides information onapparent overall kinetics as well as deactivation parameters and would seem to provide arapid method for screening of reaction/deactivation behavior. Accordingly thedeactivation order was found to be 3.72. The obtained correlation of deactivation predictsthe activity pattern under the applied reaction conditions, closely mimics those observedexperimentally, and spans those obtained from empirical correlations.


Article
KINETICS AND MECHANISM STUDIES OF OXIDATION OF Α-AMINO ACIDS BY N-BROMOSUCCINIMIDE

Authors: Hassan Hadi --- Ammar J. Mohammed
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2007 Volume: 10 Issue: 2 Pages: 66-72
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

Kinetics and mechanism studies of oxidation of some α-amino acids (Proline, Arginine, Alanine) (AA) by N-Bromosuccinimide (NBS) by using conductivity method was carried out. The kinetic study showed that the reaction was first order with respect to NBS and AA. The effect of addition of HClO4 to the reaction was negative on the rate of reaction. The reaction was carried out at different temperatures in which were calculated. The rate of reaction of AA was as follows: Proline > Arginine > Alanine

تـم دراسة حركيـة وميكانيكية أكسدة بعض الحوامض الفـا-امينية بواسطـة N-Bromosuccinimide بأستخدام التوصيلية. بينت الدراسة الحركية أن التفاعل من المرتبة الاولى لكل من الحوامض الفا-امينية وN-Bromosuccinimide . وجد أن إضافة حامض HClO4 ذات تأثير سلبي على سرعة التفاعل. تم دراسة التفاعل بدرجات حرارة مختلفة وتم حساب الدوال الثرموديناميكية للتفاعل. وجد أن سرعة تفاعل الأكسدة للحوامض الامينية كانت بالترتيب الآتي:Proline > Arginine > Alanine.


Article
Effect of Transformation Temperature on Microstructure andMechanical Properties of Bainite
دراسة تأثير درجة حرارة التحول على البنية المجهرية

Author: Hala Salman Hasan
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2012 Volume: 30 Issue: 13 Pages: 2165-2174
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Fully bainitic microstructure can be obtained by isothermal transformation attemperatures within the range of bainite transformation. Both transformation temperatureand time determine the phase fraction, the scale of the resultant microstructure and thecarbone content of the retained austenite, which in turn determine the mechanicalproperties.In this study, the thermomechanical simulator was used to obtained the fully bainiticmicrostructure for the high carbon alloy steel (0.78%C) at a different bainitetransformation temperatures (200 to 350°C) in order to study the effect of the isothermaltransformation temperature on the resultant mechanical properties.It has been concluded from the detailed analysis of the microstructure, the dilatometricdata and the mechanical properties (hardness and tensile properties) that finer bainite andless retained austenite phase fraction can be obtained by transformation at lowertemperatures, and that leads to exceptional mechanical properties (Hardness ≈ 660 HV,and Tensile strength ≈ 2 Gpa).

يمكن الحصول على بنية مجهرية من البينايت عن طريق التحولات الايزوثيرمية ضمن مدى درجاتحرارة التحولات الطورية الباينايتية، ان درجة حرارة وزمن التحول الطوري يحددان الكسر الحجميودرجة نعومة البنية الناتجة وكذلك المحتوى الكاربوني للاوستنايت المتبقي والذي بدوره يحدد الخواصالميكانيكية الناتجة.تم في هذا البحث استخدام جهاز محاكي للتحولات الحرارية الميكانيكة للوصول الى البنية الباينايتية0.78% ) بدرجات حرارة تحول ايزوثيرمي مختلفة تتراوح من 200 C) للصلب العالي الكربونالى 350 م° وذلك لدراسة تأثير درجة حرارة التحول على الخواص الميكانيكية الناتجة. لقد تم التوصل من خلال التحليل الدقيق للبنية المجهرية الناتجة وبيانات التغيير في الابعاد وكذلك نتائجفحوصات الصلادة ومقاومة الشد الى امكانية الحصول على بينايت ناعم جدا مع انخفاض درجات حرارة2 مقاومة Gpa ≈ التحول الايزوثيرمي مما يقود الى خواص ميكانيكية عالية ( 660 صلادة فيكرز وشد).


Article
Monte Carlo Simulation of Electronic Kinetics in Gas Discharge

Authors: A.B. Kadhem --- B.H. Hamad
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2005 Volume: 1 Issue: 3 Pages: 3-5
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

The phenomenon of electrical gas discharge is present in manyapplications of plasma physics. Calculation of electrons motion tracingin gases are described. The backscattering probability of electrons tothe cathode has been estimated for values of E/P0 ratio from 10 to 200V.cm-1.torr-1 and for emission energies up to the lowest excitationpotential. The primary ionization coefficients and drift velocities wereevaluated for values of E/P0 ratio from 20 to 400 V.cm-1.torr-1. Theequilibrium of swarm with the field was considered in detail. It isshown that for uniform fields, deviations from exponential growth ofcurrent with increasing electrode separation occur if the interelectrodevoltage is not at least three times the mean energy ofelectrons impinging on the anode.


Article
Investigation of Amorphous to Crystalline Transition in Glassy Se80Te20 and Se70Te20M10 (M = Ag, Cd, Sb) Alloys

Authors: N. Mehta --- A. Kumar
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2005 Volume: 1 Issue: 3 Pages: 7-13
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

Calorimetric measurements have been performed in binary Se80Te20 and ternary Se70Te20M10 (M=Ag, Cd, Sb) alloys to study the effect of metallic additives (Ag, Cd, Sb) on the crystallization kinetics in Se80Te20 alloy. Three different non-isothermal methods Kissinger’s method, Matusita-Sakka theory and Augis-Bennett approximation method have been used in the present study. Different kinetic parameters such as the activation energy of crystallization (EC), the order parameter(n), the growth morphology parameter (m), the rate constant (K) and its frequency factor (Ko) have been determined. The effect of third element on crystallization temperature of binary Se80Te20 is explained in terms of Arrhenius dependence of rate constant K(T). The increasing sequence of activation energy of crystallization in ternary Se70Te20M10 (M=Ag, Cd, Sb) alloys is explained in terms of their average bond strength.


Article
Crystallization and Glass Transition Kinetics in Se90Sb10-xAgx Glassy Alloys

Authors: A. Kumar --- D. Kumar --- N. Mehta --- S. Srivastava
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2013 Volume: 9 Issue: 1 Pages: 7-13
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

Alloys of Se100-xSb10-xAgx (x=2, 4, 8) glassy system are obtained with rapid quenching. Calorimetric studies have been performed at different heating rates under non-isothermal conditions. Well defined endothermic and exothermic peaks are obtained at glass transition (Tg) and crystallization temperatures (Tc). In the present study, the glassy alloys are found to have double glass transition and crystallization temperatures. From the dependence of the glass transition temperature on the heating rate β, the activation energy of glass transition has been calculated on the basis of Moynihan and Kissinger models. The value of (Tc–Tg) and stability parameters have also been calculated for each composition for both the phases. Value of Eg is found to be decreased with increase in concentration of Ag. The values of (Tc-Tg) is highest for the sample with 8 at % of Ag. Activation energy of crystallization (Ec) has also been calculated using the well-known Kissinger’s relation, Matusita–Sakka theory and the method of Augis and Bennett. A good agreement has been found in all the three methods. The activation energy of crystallization is found to decrease with increasing concentration of Ag.


Article
Kinetic and Mechanism of Oxidation of Formic acid by Cerium (IV)

Author: Rawaa Hussein Ali
Journal: Journal of University of Babylon مجلة جامعة بابل ISSN: 19920652 23128135 Year: 2013 Volume: 21 Issue: 7 Pages: 2491-2497
Publisher: Babylon University جامعة بابل

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Abstract

Kinetic and mechanism studies of the oxidation of Formic acid(FA) by Cerium sulphate have been carried out in acid medium of sulphuric acid. The UV- Vis. Spectrophotometric technique was used to follow up the reaction and the selected wavelength to be followed was 320 nm. The kinetic study showed that the order of reaction is first order in Ce(IV) and fractional(0.66) in FA. The effect of using different concentration of sulphuric acid on the rate of the reaction has been studied and it was found that the rate decreased with increasing the acid concentration. Classical organic tests was used to identify the product of the oxidation reaction, the product was just bubbles of CO2.

تم دراسة حركية وميكانيكية اكسدة حامض الفورميك في الوسط الحامضي من حامض الكبريتيك . استخدمت تقنية الاشعة فوق البنفسجية- المرئية لمتابعة التفاعل عند الطول الموجي 320 nm . بينت الدراسة الحركية ان التفاعل من المرتبة الاولى بالنسبة للسيريوم الرباعي والمرتبة الكسرية(0,66) بالنسبة لحامض الفورميك .تم دراسة تأثير تغيير تركيز حامض الكبريتيك على سرعة التفاعل ووجد ان سرعة التفاعل تقل بزيادة تركيز حامض الكبريتيك تم استخدام الكشوفات العضوية الاولية لتشخيص ناتج الاكسدة ووجد ان ناتج التفاعل هو عبارة عن فقاعات غاز ثاني اوكسيد الكاربون.

Keywords

Cerium --- IV --- Kinetics --- Oxidation --- Formic Acid.


Article
MODELING THE KINETICS OF HYDROXYAPATITE CATALYZED TRANSESTERIFICATION REACTION
نمذجة حركية تفاعل الترانساسترة المحفزة بواسطة الهيدروكسي اباتايت

Author: Ali A. Jazie Al-Khaledy
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2015 Volume: 8 Issue: 1 Pages: 21-37
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

A bone waste was utilized as a cost effective catalyst for the transesterification of Indian mustard oil. This high efficient and low-cost waste catalyst could make the biodiesel production from Indian mustard oil competitive with petroleum diesel.The catalysts samples were calcined at different temperatures (800oC, 900oC and 1000oC) for 2 hrs. The samples were characterized by using X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and BET surface area analyzer. A simple model was used to study the kinetics of hydroxyapatite-catalyzed transesterification of mustard oil. The optimum conditions for biodiesel production were (reaction temperature (60oC), a methanol-to-oil molar ratio (20:1) and catalyst amounts (18% based on oil weight). Two steps were concluded for the transesterification process, the initial one is the triglyceride (TG) mass transfer controlled region, The second one is the chemical reaction controlled region. The high adsorbed methanol concentration and the lower availability of active specific catalyst surface caused the TG mass transfer controlled region.Increasing the catalyst amount in the transesterification process caused increasing both the TG mass transfer and chemical reaction rates.The effect of mixing conditionsin the transesterification process was predicted in the modeling strategy.

مخلفات العظام استخدمت كعامل مساعد واطئ الكلفة لتفاعل الترانساسترة لتحويل زيت الخردل الهندي الى ديزل حيوي. يعتبر استخدام هكذا عامل مساعد واطئ الكلفة عامل مهم في جعل انتاج الديزل الحيوي منافس لوقود الديزل من الاصل النفطي.إن حركية التفاعل المحفز بواسطة العامل المساعد (Hydroxyapatite) تم دراستها بظروف متوسطة ( درجة حرارة 60 م, نسبة الايثانول الى الزيت 20:1 وكمية العامل المساعد 18% بالاعتماد على وزن الزيت).نماذج العوامل المساعدة تم دراسة خصائصها باستخدام تقنيات (XRD, FTIR, BET surface area). الدراسة الحالية بينت إن عملية (Transesterification) تتضمن مرحلة ابتدائية محددة بانتقال الكتلة لل ( TG) ثم مرحلة سريعة وأخيرا مرحلة محددة بسرعة التفاعل الكيمياوي. إن تحديد انتقال المادة لل (TG) كان سببه قلة توفر المساحة النوعية الفعالة للعامل المساعد نتيجة الامتزاز العالي للميثانول على سطح العامل المساعد. انتقال المادة لل (TG) وسرعة التفاعل الكيمياوي كلاهماازداد مع زيادة كمية العامل المساعد. الإستراتيجية المتبعة لنمذجة العملية تأخذ بنضر الاعتبار تأثير ظروف الخلط على عملية ال


Article
Biosorption of Lead, Cadmium, and Zinc onto Sunflower Shell: Equilibrium, Kinetic, and Thermodynamic Studies

Author: Ahmed A. Mohammed
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2015 Volume: 16 Issue: 1 Pages: 91-105
Publisher: Baghdad University جامعة بغداد

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Abstract

The present study deals with the application of an a bundant low cost biosorbent sunflower shell for metal ions removal. Lead, Cadmium and Zinc were chosen as model sorbates. The influences of initial pH, sorbent dosage, contact time, temperature and initial metal ions concentration on the removal efficiency were examined. The single ion equilibrium sorption data were fitted to the non-competitive Langmuir and Freundlich isotherm models. The Freundlich model represents the equilibrium data better than the Langmuir model. In single, binary and ternary component systems,Pb+2 ions was the most favorable component rather than Cd+2 and Zn+2 ions. The biosorption kinetics for the three metal ions followed the pseudo-second order kinetics indicating that the chemical sorption was the rate-limiting step. The thermodynamic parameters including free energy (∆G0), enthalpy and entropy changes for Pb2+,Cd2+ and Zn2+ ions indicated that the sorption process was feasible,spontaneous,and endothermic in the temperature range 20-50 0 C .Desorption of the three metals ions from the biosorbent was effectively achieved in a 0.2 mol L-1 HCl solution.


Article
Enhancement effect of almond oil on transdermal penetration of flurbiprofen topical gel
تأثير زيت اللوز على النفوذية الجلدية لمادة (flurbiprofen topical gel)

Author: Muder AL Haydar
Journal: journal of kerbala university مجلة جامعة كربلاء ISSN: 18130410 Year: 2015 Volume: 13 Issue: 2 Pages: 156-163
Publisher: Kerbala University جامعة كربلاء

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Abstract

Flurbiprofen is related to nonsteroidal anti-inflammatory drugs. The aim of this study is to investigate use of almond oil as enhancer to increase drug skin penetration. Five selected formulas of flurbiprofen gel with five different concentration of almond oil were prepared. Only one formula was prepared without almond oil. The prepared gels were evaluated for several physico-chemical parameters to justify their suitability for topical use. The in vitro drug release studies were carried out by using Franz cell diffusion apparatus across synthetic membrane. The permeation profile of various formulations also showed that the adding an enhancer in individual formula affected the permeation of the drug. Drug permeation increased with increased concentration of almond oil.

فلوربايبروفن يعود الى الادوية المضاد للالتهاب الغير سترويدي . الهدف من هذه الدراسة هو معرفة تاثير زيت اللوز كماده محفزة على زيادة نفاذية الدواء للجلد. حضرت خمسة صيغ من مستحضر جل الفلوربايبروفن مع مختلف النسب من زيت اللوز. كما حضرت صيغه واحد من الجل بدون زيت اللوز. جميع الصيغ المستحضرة فحصة من الناحية الفيزياوية والكيمايوة لمعرفة ثباتية وملائمة المستحضر للجلد. دراسة التحرر الدوائي في المختبر قد تمت من خلال استعمال الفرانز سل باستعمال الغشاء المصنوع. وضع النفاذية لمختلف الصيغ تظهر تأثير المحفز على نفاذية الدواء. نفاذية الدواء قد ازدادت كلما زاد تركيز زيت اللوز المستعمل .

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