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Article
Experimental Analysis of Heat Transfer Enhancement and Flow with Cu,TiO2 Ethylene glycol Distilled Water Nanofluid in Spiral Coil Heat

Author: Khalid Faisal Sultan
Journal: Tikrit Journal of Engineering Sciences مجلة تكريت للعلوم الهندسية ISSN: 1813162X 23127589 Year: 2017 Volume: 24 Issue: 3 Pages: 63-77
Publisher: Tikrit University جامعة تكريت

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Abstract

This experimental investigation was performed to improve heat transfer in the heat exchanger (tube of shell and helically coiled (using nanoparticles for turbulent parallel flow and counter flow of distilled water (Dw) and ethylene glycol (EG) fluids. Six types of nanofluids have been used namely: copper – distilled water, copper – distilled water and ethylene glycol, copper – ethylene glycol, titanium oxide – distilled water, titanium oxide – distilled water and ethylene glycol, titanium oxide – ethylene glycol with 0.5%,1%,2%,3% and 5% volume concentration as well as the range of Reynolds number are 4000 – 15000. The experimental results revel that an increase in coefficient of heat transfer of 50.2 % to Cu – Dw, 41.5% to Cu – ( EG + Dw ), 32.12 % for Cu – EG , 36.5% for TiO2 – Dw, 30.2 % to TiO2 – ( EG + Dw) and 25.5%, to TiO2 – EG . The strong nanoconvection currents and good mixing caused by the presence of Cu and TiO2 nanoparticles. The metal nanofluids give more improvement than oxide nanofluids. The shear stress of nanofluids increases with concentration of nanoparticles in case parallel and counter flow. The effect of flow direction insignificant on coefficient of overall heat transfer and the nanofluids behaves as the Newtonian fluid for 0.5%,1%,2%,3% and 5%. Good assent between the practical data and analytical prediction to nanofluids friction factor which means the nanofluid endure pump power no penalty. This study reveal that the thermal performance from nanofluid Cu – Dw is higher than Cu – (EG + Dw) and Cu – EG due to higher thermal conductivity for the copper and distilled water compared with ethylene glycol.


Article
Self Expandable Metallic Stents in Malignant Biliary Obstruction: Safety and Efficacy

Authors: Rayadh Asmer Zaydan --- Qasim Lefta Abbas --- Rabah Hiab Asreah
Journal: Iraqi Academic Scientific Journal المجلة العراقية للاختصاصات الطبية ISSN: 16088360 Year: 2011 Volume: 10 Issue: 1 Pages: 13-17
Publisher: The Iraqi Borad for Medical Specialization المجلس العراقي للاختصاصات الطبية

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Abstract

ABSTRACT: BACKGROUND: Endoscopic stenting has become widely accepted procedure for the relief of jaundice in patients with malignant biliary obstruction. It may offer lower morbidity and mortality, shorter hospitalization, and diminished overall cost compared with surgical or radiological approaches. OBJECTIVE: To assess the efficacy of the self expendable metallic stents in treatment of the patients with biliary stricture due to malignant tumors, and to compare this efficacy between proximal and distal obstruction. PATIENTS AND METHODS: SEMS were deployed during endocopic retrograde cholangiopancreatography (ERCP) in a total of 41patients with malignant biliary obstruction (proximal or distal) . Clinical success was defined as the improvement of the laboratory data and a decrease of the bilirary dilatation by follow up ultrasound imaging. Stent dysfunction was defined as recurrence of jaundice or cholangitis, is confirmed by ERCP or simply by elevated cholestatic parameters and treated by insertion of a plastic stent or second metallic stent inside the old one. RESULTS: Stent placement was achieved in 38 of 41 patients (92.7%) with malignant bile duct obstruction. SEMS was failed to be placed in 3 patients (1 with pancreatic cancer and 2 with proximal cholangiocarcinoma).Clinical improvement was seen in 36 of 38 patients (94.7%). In 4 patients (10.5%) cholangitis had developed.The overall stent patency time was 37.88 + 18.59 weeks (range 16-76 week). Analysis in subgroup of patients classified according to the site of obstruction (34with distal and 7 with proximal biliary obstruction).The overall success (technical and clinical) was significantly higher in the distal group (33/34, 97.1%) than in the proximal group (3/7, 42.9%); p-value was 0.02. CONCLUSION: SEMS implantation is a feasible , palliative method for inoperable malignant biliary obstruction. The clinical and the technical success of biliary drainage by SEMS is better achieved in distal than in proximal tumors with hilar infiltration by the tumor


Article
Recovery of Cu (II) from Model Water using Emulsion Liquid Membrane (ELM) Technique

Authors: Dr. Mohammed D. Salman محمد دخيل سلمان --- Adnan Abdul Hussain
Journal: University of Thi-Qar Journal for Engineering Sciences مجلة جامعة ذي قار للعلوم الهندسية ISSN: 26645564/26645572 Year: 2013 Volume: 4 Issue: 1 Pages: 16-24
Publisher: Thi-Qar University جامعة ذي قار

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Abstract

The proper condition of the emulsion liquid membrane (ELM) technique for the recovery and concentration of copper (II) from model water is investigated. The ELM is a solution of di (2-ethylhexyl) phosphoric acid in kerosene and sorbitan monooleate Span 80 as surfactant. The extraction efficiency of the metallic ion in the ELM in batch tests is determined. The results show good extraction percentage in relatively period of time (15 minutes) under the following conditions: pH of the feed is 8; feed concentration of 500 ppm, carrier concentration of di (2-ethyl-hexyl) phosphoric acid (D2EHPA) 4% and treatment ratio (volume of external phase to volume of emulsion phase) of 2.

الظروف المثلى لتقنية الغشاء النفاذي السائل لازالة وتركيز النحاس الثنائي التكافؤ قد اختبرت في هذه الدراسة. يتكون الغشاء النفاذي السائل من محلول داي(2- ايثايل هكسايل) حامض الفوسفوريك في النفط الابيض والمادة السطحية سوربيتون مونولييت (سبان 80). كفاءة الاستخلاص للمعدن النحاس الثنائي التكافؤ في تقنية الغشاء النفاذي السائل باستخدام نظام دفعي قد استخدمت. اوضحت النتائج نسبة استخلاص جيدة في وقت قصير يقدر بـ( 15) دقيقة بالظروف التالية: الدالة الحامضية (8) ، تركيز الداخل (500 ملغم /لتر)، تركيز الحامل (4%) ونسبة المعاملة (2).


Article
Characterizations of Hydroxyapatite Thin Films Deposited by Spray Pyrolysis on Titanium Substrates for Bone Implant Applications

Authors: Walid K. Hamoudi --- Raid A. Ismail --- Hadeel F. Abbas
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2014 Volume: 10 Issue: 3 Pages: 11-16
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

Hydroxyapatite (HAp) synthesis was accomplished by spray pyrolysis to coat titanium bone implant with a thin film of this material. Thin films of HAp were prepared under different deposition temperatures and spraying time. Fourier transform infra-red spectroscopy (FTIR), atomic force microscope (AFM), X-ray diffractrometer (XRD), and Vickers’s hardness measurements were employed to characterize the synthesized films. The results indicated titanium surfaces coated by 224.1 HV, 8.59 nm thick carbonated hydroxyapatite films of 1.33 nm surface roughness.


Article
The Effect of Metal Surface Treatment before Reporcelainization for Ceramic Repair After Adhesive Fracture of Ceramo-Metallic Restoration

Author: Suhayla Reda Albanai
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2015 Volume: 12 Issue: 1 Pages: 47-65
Publisher: Babylon University جامعة بابل

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Abstract

The high cost of the precious metals has simulated interest in less expensive alloys for the casting of Crown & Bridge. Several non precious metal alloys based on Nickel and/or Cobalt Chromium alloys have become commercially available for the use with fusing porcelain (ceramic).The purpose of the present work was two folds:1-To investigate the effect of different metal surface treatment (sandblasting, grinding and grinding followed by sandblasting) before reprocelainization (reapplication of porcelain after adhesive fracture) of the bare metal on the bond strength.2-To give some light on the mechanism of metal ceramic bonding through the use of metallographic microscopic study.Two non-precious dental casting alloys Nickel- Chromium and Cobalt- Chromium alloys and one type of dental ceramic were used in this study. The conclusions from the study weresandblasting increases the bond strength of metal/ceramic interface for both the investigated alloys, and the Cobalt- Chromium alloy showed better bond strength with sandblasting than the Nickel- Chromium.


Article
Effect of disinfectant agents on certain physical and mechanical properties of type IV dental stone

Authors: Hanan Abdul- Rahman Khalaf حنان عبد الرحمن خلف --- Mithaq Radhi Mohammed ميثاق راضي محمد
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 1 Pages: 24-31
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Dental stone casts come into contact with impression materials and becomes susceptible to cross contamination from saliva and blood. This study was done to evaluate the physical and mechanical properties of dental stone type IV after treatments with various disinfecting agents and regimes (methods).Materials and Methods: Type IV dental stone and different types of disinfecting agents were used and divided into seven groups: G1: dental stone without disinfection (control group), G2: dental stone mixed with silver nitrate powder 0.5% , G3: dental stone mixed with silver nitrate powder 1%, G4: dental stone mixed with copper sulfate powder 0.5%, G5: dental stone mixed with copper sulfate powder 1% ,G6: dental stone immersed in propanol 70% and G7: dental stone immersed in ethanol 70%.Setting time, linear setting expansion, surface detail reproduction, compressive strength of type IV dental stone as well as compatibility with auto mixing addition silicone impression material were evaluated. The statistical analysis were conducted by ANOVA test followed by LSD test (p<0.05), also chi square test was used.Results: The compressive strength, linear setting expansion, surface detail reproduction and compatibility of stone specimens was affected to a higher extent by mixing with silver nitrate powder 1%, copper sulfate powder 1% while treating the stone specimens with the disinfecting powders at low concentrations as well as immersion of stone specimens in either ethanol or propanol for 15 minutes produce less effect on the previous tested properties. Conclusion: Silver nitrate 0.5%, copper sulfate 0.5% powders as well as 15 minutes immersion in 70% ethanol or 70% propanol did not promote adverse alterations in most of evaluated properties of type IV dental stone


Article
Synthesis and Characterization of P3HT Metal Nanoparticles Hybrid Junction
تصنيع وتشخيص المفرق الهجين بولي (3 - هيكسيل ثيوفين) والدقائق المعدنية النانوية

Authors: Mustafa Ahmed مصطفى احمد مصطفى --- Estabraq T. Abdullah استبرق طالب عبد الله
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2019 Volume: 17 Issue: 43 Pages: 122-127
Publisher: Baghdad University جامعة بغداد

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Abstract

Due to the important of potential properties of metal-semiconductor nanostructures, conductive Poly(3-hexylthiophene-2, 5-diyl) P3HT with (Al, Ag and Cu) as metallic nanoparticles (NPs) hybrid was synthesized. Pulsed Laser Ablation (PLA) technique was used to synthesis the metallic nanoparticles in P3HT as a liquid. The morphological and structural properties of pure P3HT and P3HT metallic nanoparticles samples were studied. The Fourier Transformer Infrared (FTIR) for all samples indicate the chemical interaction between the polymer and the nanoparticles. The formation of the nanoparticles was informed by Scanning Electron Microscopic (SEM) analysis and the particle size for nanoparticles was around 50 nm. Energy Dispersive X-ray (EDX) spectra show the existing of metallic nanoparticles. Hall effect showed the n-type conductivity for P3HT-ALNPs and P3HT-CuNPs samples while for P3HT-AgNPs was p-type conductivity which may be due to the differences of work function.

نتيجة للاهمية البالغة للخصائص المحتمله لمعدن-شبه موصل للتراكيب النانويه, تم في هذا العمل تصنيع مفرق هجين من بولي (3- هيكسيل ثيوفين) والدقائق المعدنية النانوية (Ag,Al,وCu) .أستُخدمت تقنية التذرية بالليزر النبضي (PLA) لتخليق الدقائق النانوية فيP3HT كسائل. دُرست الخصائص التشكيلية والتركيبة لعينات البوليمر النقي P3HT وعينات البوليمر والدقائق النانوية المعدنية. اشارت الأشعة تحت الحمراء لمحول فورييه (FTIR) لجميع العينات إلى التفاعل الكيميائي بين البوليمر والدقائق النانوية المعدنية. وثقت تشكيل الجسيمتن النانوية عن طريق تحليل المسح الإلكتروني المجهري (SEM) وكان حجم الجسيمات لعينات البوليمر مع الدقائق النانوية المعدنية بحدود 50 نانومتر. تُظهر أطياف الطاقة المشتتة من أشعة الطاقة (EDX) كمية الجسيمات النانوية المعدنية الموجودة. اظهر تاثير هول توصيلية نوع n لعينات البوليمر مع الدقائق النانوية للالمنيوم والنحاس بينما التوصيلية نوع p لعينة البوليمر-الدقائق النانوية للفضة ويرجح السبب الى اختلاف دالة الشغل.

Keywords

P3HT --- metallic nanoparticles --- Ag --- Al --- Cu.


Article
Effect of Lanthanum Addition on the Microstructure ofMg-4Al Alloy
تاثير اضافة معدن اللنثانيوم على خصائص سبيكة المغنسيوم - 4% المنيوم

Author: Ahmed A. Moosa احمد علي موسى
Journal: Al-Khwarizmi Engineering Journal مجلة الخوارزمي الهندسية ISSN: 18181171 23120789 Year: 2011 Volume: 7 Issue: 2 Pages: 75-82
Publisher: Baghdad University جامعة بغداد

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Abstract

This research was to determine the effect of rare earth metal (REM) on the as-cast microstructure of Mg-4Al alloy.
The rare earth metal used here is Lanthanum to produce Mg-4Al-1.5La alloy. The microstructure was characterized by
optical microscopy. The phases of this alloy were identified by X-ray diffraction. The microstructure of Mg-4Al
consists of &#945;-Mg and grain boundaries with precipitated phase particles. With the addition of Lanthanum, three distinct
phases were identified in the X-ray diffraction patterns of the as cast Mg-4Al-1.5La: Mg, Al11La3, Al4La. The Mg17Al12
phase was not detected. The addition of Lanthanium increases the hardness and decrease the wear rate of Mg-4Al.

يهدف هذا البحث الى دراسة تاثير اضافة عناصر الارض النادرة على سبائك (Mg-4Al) والحيلولة دون اكسـدة المغنيسيوم أو احتراقه وأنتاج سبيكة (Mg-4Al-1.5 La).كما تضمن البحث الفحوصات المجهرية وفحص الأشعة السينية لمعرفة الأطوار الناتجة في سبيكة ( (Mg-4Al-1.5 La. أظهرت النتائج أن سبيكة ((Mg-4Al تحتوي على الطور ( α- Mg) مع وجود ترسبات على الحدود البلورية .اما الاطوار في سبيكة ( (Mg-4Al-1.5 La فهي . Mg, Al11La3, Al4La مع عدم ظهور الطور Mg17Al11 . ان اضافة اللنثانيوم يؤدي الى زيادة الصلادة وانخفاض معدل البلى


Article
Simulation of Casting Solidification Parameters in Metallic Mould

Authors: Akeel D. Subhi --- Ayad M. Takhakh
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2009 Volume: 15 Issue: 1 Pages: 3482-3491
Publisher: Baghdad University جامعة بغداد

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Abstract

In this work, numerical method approach has been used to simulate the solidification parameters of an eutectic aluminum-silicon alloy in chilled metallic mould with copper. The approach is based on the solution of heat flow equations of the casting and mould. In addition, the latent heat is treated as a boundary condition between the liquid and solid phase. The results showed that different behaviors of solidification parameters are obtained along the casting. Furthermore, the simulation approach of solidification parameters in conjunction with the microstructure indicated that it is possible, to a large degree, giving a knowledge about the microstructural features for any alloy system.

تم في هذا البحث استخدام الطريقة الرقمية في محاكاة متغيرات التجمد لسبيكة الالمنيوم-سليكون الايوتكتيكية في قالب معدني مزود بمصقع من النحاس. اذ تستند الطريقة المستخدمة على حل معادلات انسياب الحرارة للمسبوكة والقالب. اضافة لذلك فقد تم اعتماد الحرارة الكامنة كظرف للحد الفاصل بين السائل والصلب. وقد اوضحت النتائج وجود اختلاف في سلوك متغيرات التجمد على طول المسبوكة. علاوة على ذلك فقد تم التوصل من خلال الربط ما بين محاكاة متغيرات التجمد والبنية المجهرية الى امكانية الاستفادة من نتائج المحاكاة لهذه المتغيرات للتنبا بالسمات المجهرية الى حد كبير ولاي نظام سبائكي.


Article
The Outcome of Retained Metallic Foreign Bodies in Upper and Lower Limbs…………...

Author: Ali Khairi Toman
Journal: Karbala Journal of Medicine مجلة كربلاء الطبية ISSN: 19905483 Year: 2009 Volume: 2 no.8, 9 Issue: 5 Pages: 692-696
Publisher: Kerbala University جامعة كربلاء

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Abstract

background: Retained metallic fragments represent a common problem thatcan be encountered in surgical practice.They could be bullets, part of bullets or other fragments and shells frombombs or mines or in rare occasion, different foreign particles from the environment.They are always the cause of patients complain to whom they refer their pain ordisabilities and sometime they insist for their removal.Operations for removal of deep retained foreign bodies are not beneficial, take longtime and consume a lot of materials and sometime could be very risky, cause moredamage and in some cases, ended without finding the foreign body.There are only few indications for removal of retained metallic fragments.Objectives: We want to assess the problem of retained metallic foreign bodies andfind the indications of their removal.Patients and Methods: This is a prospective study of 300 patients with retainedmetallic foreign bodies presented to the out-patient department of Alhindiya generalhospital between July 2006 and July 2008 with different complains.Results: Three hundred patients were included in this study, 264 patients(82%) weremales and 36 patients (18%)were females, 270 patients about (90%) presented withinthe first week after injury, 243 patients(81%) have foreign bodies in the upper andlower limbs, 45 patients(15%) in the trunk and 12 patients(4%) in the head & neck.Conclusion: Palpable foreign body can be removed safely and successfully in most ofthe cases while deep foreign body should not be removed unless there are indications.

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