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Article
Radiation contrast improvement by suitable choice of x-ray radiation spectrum
تحسين التباين الاشعاعي بالاختيار المناسب لطيف الاشعة السينية

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Abstract

Different bremsstrahlung spectra from tungsten anode x-ray tube generated at 30, 40 and 50 kV have been examined theoretically and experimentally for an attempt to find a most suitable spectrum to radiograph a test object of 0.01 cm thickness of Cu and Ag. The high contrast using this suitable spectrum is demonstrated and the possible effects of fluorescent radiation are discussed.

تم اختيار اطياف اشعة كبح مختلفة منبعثة من انبوب الاشعة السينية باستخدام هدف التنكستن بفرق جهد 30 ,40 و 50 كيلو فولت نظريا وعمليا في محاولة لايجاد طيف مناسب لتصوير الجسم الاختباري المتكون من النحاس والفضة بسمك 0.01 سم شعاعيا.جرى تحقيق التباين الاشعاعي العالي باستخدام هذا الطيف المناسب وكذلك توضيح تاثيرات الاشعة التفلورية.


Article
Residual Stress effect on Fatigue Behavior of 2024- Aluminum alloy

Authors: Riyadh A. Al-Taie --- Farag Mahel Mohammed --- Ahmed N.Al-khazraji
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 3 Pages: 567-578
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In the present work the effect of residual stress on the fatigue behavior of2024 Aluminum alloy was studied experimentally and numerically usingfinite element method with aid of ANSYS-11 software. All the testspecimens treated by annealing before any process to remove the internalstresses due to cold work. Residual stresses were imparted to the fatigue testsspecimens by heat treatment, pre-strain and welding. X-Ray diffraction wasused to measure the residual stress.The heat treatment; done on the test specimens with different temperature of(420, 450, 480, and 510) oC. After heat treatment; alloy mechanical propertieswere improved. For the heat treated specimens as the temperature increasedthe compressive residual stress increased to (27.06, 41.43, 72.8 and 85.6)MPa. That leads to increase the endurance fatigue limit by (32.93%, 40.48%,50.68% and 61.03%) respectively than other alloy as received. While in prestrain groups; the test specimens loaded to (265, 290, 315 and 340) MPa by atension test machine. As the applied load series were increased thecompressive residual stress increased to (16.51, 25.62, 51.54 and 62.44) MPawhich improve the endurance fatigue limit by (7.68%, 16.19%, 24.98%, and46.45%), respectively. An electrical arc and metal inert gas were used inwelding series to weld the test specimens, that present a tensile residual stressof (76.93 and 72.66) MPa, which reduces the endurance fatigue limit by(23.45% and 16.08%), respectively. The numerical results present fatiguebehavior, deflection and stress at any load, and show a reasonable agreementresults with an experimental one.


Article
Study of Linear Shrinkage for Siliceous Materials to Meet Insulating Requirements
دراسة التقلص الخطي للمواد السيليسية المحققة للمواصفة العازلية

Authors: Jubair, S.I شوكت إسماعيل جبير --- Kamis, R.A رعد عزاوي خميس --- Rassen, F.A فاضل عبد رسن
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2011 Volume: 9 Issue: 16 Pages: 73-78
Publisher: Baghdad University جامعة بغداد

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Abstract

Iraqi siliceous rocks were chosen to be used as raw materials in this study which is concern with the linear shrinkage and their related parameters. They are porcelinite from Safra area (western desert) and Kaolin Duekla, their powders were mixed in certain percentage, to shape compacts and sintered. The study followed with thermal and chemical treatments, which are calcination and acid washing. The effects on final compact properties such as linear shrinkage were studied. Linear shrinkage was calculated for sintered compacts to study the effects of calcination processes, chemical washing, weight percentage, sintering processes, loading moment were studied on this property where the compacts for groups is insulating materials.Linear firing shrinkage test is very important in ceramic industries, when in some uses most be calculated the ceramic body volume before product.The results indicate that some of these groups satisfy ability the required linear firing shrinkage property for electrical insulator, so they are an ability to be used in industry.

يتضمن موضوع البحث اختيار نوع من الصخور السيليسية العراقية كمواد أولية وهي صخور البورسيلينايت من موقع الصفرة في الصحراء الغربية والكاؤولين العراقي (سيليكات) / دويخلة وخلط مساحيقهما بنسب وزنية معينة لتشكيل مكبوسات وتلبيدها ودراسة خواص التقلص الخطي وتأثير بعض العوامل المرتبطة بالعينات المشكلة من هذه المواد. تم إجراء معاملات حرارية (كلسنة) ومعاملات كيميائية (غسل بالحامض) للمواد الأولية ودراسة تأثيرها على الخواص النهائية للمكبوسات (التقلص الخطي). تم حساب التقلص الخطي للمكبوسات الملبدة والمحضرة من هذه الخلطات بهدف معاينة تأثير؛ عمليات الكلسنة والغسل الكيميائي وإضافة الكاؤولين وعمليات التلبيد ومقدار التحميل على تلك الخواص. علما أن هذه المكبوسات هي مادة عازلة أي أنها ناجحة في الفحص الحراري والكهربائي ويعد فحص التقلص الخطي وقياسه ذا أهمية بالغة في الصناعات السيرامكية حيث يتوجب في بعض الاستخدامات المعتمدة في الصناعات السيرامكية تحديد حجم الجسم السيراميكي المنتج وأبعاده قبل عملية تصنيعه، وبذلك إن النتائج تشير إلى إمكانية تشكيل نماذج صناعية من بعض الخلطات المختارة بالمواصفة المطلوبة في صناعة العوازل.


Article
Does Normal Chest X ray in Patients with Chronic Cough Exclude Pulmonary tuberculosis?

Authors: Mohammad Yahya Abdulrazaq --- Abdulla Janger Minshed
Journal: Iraqi Academic Scientific Journal المجلة العراقية للاختصاصات الطبية ISSN: 16088360 Year: 2011 Volume: 10 Issue: 1 Pages: 130-133
Publisher: The Iraqi Borad for Medical Specialization المجلس العراقي للاختصاصات الطبية

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Abstract

ABSTRACT:BACKGROUND:Tuberculosis is the second infection in causing deaths from infectious agent in the world, currently in Iraq approximately 67% of new cases of Tuberculosis involve the lung only ,cough is the most common symptom of pulmonary Tuberculosis , pulmonary Tuberculosis nearly always causes detectable abnormalities on chest film, but still atypical or absent radiologic findings can occur.OBJECTIVE:This study was designed to determine whether in patients with chronic cough normal chest X ray exclude pulmonary tuberculosis.PATIENTS AND METHODS:One hundred seventy two patients attending the respiratory clinic, complaining from chronic cough and they are suspected cases of tuberculosis, were enrolled in this study. A full medical history and physical examination was done then a chest X ray was ordered, for those with normal chest X ray finding (seventy seven patients), sputum smear for acid fast bacilli (AFB) ordered .RESULTS:47 females (61%), 30 males (39%) with chronic cough with females to male ratio = 1.56/1.The age ranged between 17-67, with mean age of 37.16 years. The age of males ranged between 18-67 and the mean was 39.32 years, the age of females ranged between 17-66 and the mean was 34.93 years. X ray finding were negative in all the patients. Positive AFB in sputum smear examination by microscopy was found in only one patient but with ENT examination it was proved to be a case of laryngeal tuberculosis not pulmonary tuberculosis.CONCLUSION:Normal chest x ray in patients with chronic cough excludes pulmonary tuberculosis


Article
Effect of carbon wt% on the iron x-ray diffraction pattern and the volume of iron unit cell.
تأثير النسبة المئوية الوزنية للكاربون على مخططات الأشعة السينية للحديد وعلى حجم وحدة الخلية

Author: Ali I. Salih علي إسماعيل صالح
Journal: kirkuk university journal for scientific studies مجلة جامعة كركوك - الدراسات العلمية ISSN: 19920849 / 26166801 Year: 2011 Volume: 6 Issue: 2 Pages: 155-165
Publisher: Kirkuk University جامعة كركوك

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Abstract

From standard x-ray diffraction chart for iron noticed that the effect of increasing in carbon wt% are accompanied with the change in the volume of the iron unit cell, after diffusion of carbon atoms it takes interstitial position between irons atoms, this will increase the edge length of the unit cell by follow the relationship (Δ c =0.11285 ×C wt%), a permanent strain happens with the change in the mean of the lattice spacing. This relation between carbon wt% and the volume of iron unit cell can be use to predict the carbon which is present in the iron alloy. The diffraction pattern act as an empirical fingerprint for carbon % and their phases.

من مخططِ حيود الأشعة السينيةِ القياسيِ للحديدِ يمكن ملاحظة تأثير الزيادة في النسبة المئوية للكاربون على الحديد حيث تكون مصحوبة بتغييرِ في حجم خليةِ الوحدةِ لمادة الحديد فبعد ألانتشار تأخذ ذرّاتِ الكاربونِ موقعاً فراغياً بينيا بين ذرّاتِ الحديدِ وهذا سَيَزِيدُ في طولِ حافةَ خليةِ الوحدةَ وفق العلاقة التالية(Δc=0.11285×Carbon wt%) و يَحْدثَ انفعال دائمَ نتيجة التغييرِ في متوسطِ البعد للمستويات المتعاقبة في المشبّكِ البلوري.هذه العلاقةِ بين النسبة المئوية للكاربون وحجم وحدة الخليةِ يمكن أن تُستَعملَ لتَوَقُّع نسبة الكاربونِ التي تتواجد في السبيكةِ الحديدية عن طريق معرفة مخططِ حيود الأشعة السينيةِ كطبعِ إصابع تجريبيِ للنسبة المئوية للكاربون المتواجد واطوارة.

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