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دراسة النشاط الاشعاعي لنماذج من التربة والماء في بغداد وكربلاء والبصرة == Determination of the Radioactivity in Soil and Water in Baghdad, Karbala and Basrah Samples

Author name: مصطفى عرب بداي علي البيضاني
General topic: Physics
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: يتضمن البحث دراسة عملية لتحديد تراكيز اليورانيوم وغاز الرادون في التربة والماء لمناطق من بغداد وكربلاء والبصرة وللتعرف على مدى تلوث تلك المناطق بالمواد المشعة بعد احداث الحرب على العراق عام 2003 .تضمن الجزء الاول ايجاد تراكيز اليورانيوم في التربة والماء باستخدام كاشف الاثر (CR - 39) حيث استخدم التفاعل U - 235(n,f)U - 236 كمصدر لشظايا الانشطار النووي وذلك بقصف نواة اليورانيوم U - 235 بالنيوترونات الحرارية من المصدر النيوتروني (Am - Be) بفيض نيوتروني حراري (5 ×103 n cm - 2 s - 1) .تم تحديد التراكيز بالحسابات المعتمدة على المقارنة مع النماذج القياسية، وقد اوضحت النتائج التي حصلنا عليها ان اعلى تركيز لليورانيوم في التربة (2.73 ppm) في منطقة التاجي واعلى تركيز لليورانيوم في الماء (2.12 ppm) في منطقة العشار. تضمن الجزء الثاني ايجاد تراكيز غاز الرادون في التربة والماء باستخدام تقنية عد اثار جسيمات الفا المنبعثة من غاز الرادون فيكاشف الاثر (CR - 39) .وقد اوضحت النتائج التي حصلنا عليها ان اعلى تركيزلغاز الرادون في التربة (666 Bq/m3) في منطقة التاجي واعلى تركيز للرادون في الماء (14 Bq/m3) في منطقة العشار. اوضحت النتائج التي حصلنا عليها بان اعلى تراكيز لليورانيوم والرادون كان في منطقة التاجي ببغداد وفي منطقة العشار بالبصرة بسبب كون تلك المناطق مسرح للعمليات الحربية ضد العراق عام 2003 . | The aim of this project is to measure the uranium and radon gas concentrations in soil and water samples taken from regions situated in Baghdad, Karbala and Basrah, and to limit the level of contamination with radionuclides for these regions during the 2003 war.The first part contains the determination of uranium concentration in soil and water samples using CR - 39 Track detector. The nuclear reaction used a source of nuclear fission fragments is 235 - U (n , f) obtained by the bombardment of U - 235 with thermal neutrons from (Am - Be) source which has flux of (5 ×103 n cm - 2 s - 1). The concentrations values were calculated by a comparison with standard samples which prepared in our laboratory.The results obtained show that the higher concentration of uranium in soil samples was (2.73 ppm) in Al - Tajii region, and the higher concentration for water samples was (2.12 ppm) in Al - Ashaar region.The second part contains the determination of radon concentration in soil and water samples using alpha - emitters registration which emits from radon gas in (CR - 39) track detector.The results show that the higher concentration for radon gas in soil samples was (666 Bq/m3) in Al - Tajii region and in water samples was (14 Bq/m3) in Al - Ashaar region.The results show the maximum values of uranium and radon concentrations were in the (Al - Tajii and Al - Ashaar) regions, because these regions were a field of military operations during the 2003 war

نظام اخفاء البيانات ذو معدل اخفاء عالي باستخدام تحويل الافين وطريقة البت الاقل اهمية == High Hiding Rate Image Steganography System Based On Affine Transform and LSB Method

Author name: محمد خليل خلاف سهيل القيسي
Supervisor name: لؤي ادور جورج | اياد عبد العزيز العاني
General topic: Physics
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: The spying and intrusion operation had been widely spread to steal the information especially with the development of computer networks (like, Internet). To prevent this danger the development of a new technology called “digital information hiding” was developed in such a way that the intruder cannot notice the existence of secret information in the media.In this project an image steganograph system is introduced. The proposed system is based on using the affine transform to represent the blocks of the secret image in terms of the blocks of the cover image. Then, the least significant bits (LSB) insertion method is utilized to hide the quantized affine transform coefficients of the secret image in the cover image. Also in this research some block indexing methods are utilized to improve (i.e, speed up) the involved trials of affine mappings. Three systems (they are traditional IFS, IFS with symmetry predictions, and IFS with symmetry prediction and blocks indexing) have been established. They used to manage the way of selecting the suitable domain (cover) to represent the range (secret) block. The domain search operation will not need to make all isometric - block tests on each domain block. The best domain isometric state is assessed using the introduced isometric predictor; which is based on the moment status of the matched block. This will significantly reduce the matching time because only one match, instead of eight, will be tested to evaluate the IFS - similarity between any range and domain block. Also, a block indexing method is introduced to filter the domain blocks, and filter - in only those domain blocks that have similar block index with that of the mapped range block to be tested using IFS - matching.Some of the well known fidelity measures (like, MSE and PSNR) have been used to asses the quality of the reconstructed image. The conducted test results indicated that the proposed improvements have reduced the required hiding time down to 6.81 second (around 80 times in comparison with the traditional scheme) without making significant degradation in image quality

دراسة متانة الربط الانتشاري بين السيراميك والمعادن في الحالة الصلبة == Investigation of the Relaibility of Diffusion Bond Strength Between Ceramic - Metals in Solid State

Author name: اروى غازي ناجي الطائي
Supervisor name: زاريه ازات سركيس | ثامر عبد الجبار جمعة
General topic: Physics
Degree: Master
Language: English
University location: Baghdad
First pages:

دراسة الفجوات المصنعة بهيئة عيوب بواسطة الاشعة السينية لمصبوبة المنيوم ومفاصل لحام الفولاذ == X - ray Radiographic Study of Simulated Voids - Like Defects in Aluminum Casting and Welded Joints in Steel

Author name: فرقد رشيد سعيد الزبيدي
Supervisor name: مازن فضيل محروك | ثامر عبد الجبار جمعة
General topic: Physics
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: This project investigates the detection and evaluation of imperfections in internal structures of castings and welded joints by x - ray radiography. Optimum radiography conditions that lead to clear and high contrast image on the radiograph were studied.Equations derived earlier for finding the size and depth of defects in castings were used in this project to test their applicability to a wide range of geometrical parameters used in radiography.The importance of non - destructive testing NDT in industry is discussed. X - ray radiography being one of the NDT techniques, has some privilege over other techniques. For example, welded joints sometimes contain internal flaw or blowholes that may escape detection by other NDT techniques but can not escape detection by x - rays. Two kinds of samples are prepared for radiography. The first sample is aluminum casting through which two different sizes of steel spheres are included. This sample was radiographed from two opposite sides and the x - ray films were analyzed.The second sample is steel plates which are welded by arc welding and then radiographed by x - rays.Imperfections in this sample such as incomplete root penetration, undercut and porosity were detected by x - ray radiography. Different conditions influencing the preparation and radiography of the above samples were studied. The prepared welded sample was radiographed three times for different high voltages (120,140,160) kV respectively with an exposure time of (80) second. The best quality image where the defects can be detected clearly if its size is (5%) of the radiographed object using (120) kV and (140) kV. Moreover the results show that the optimum film gradient was found at (140)kV and the contrast is better than obtained with (120)kV while darkening image was found at (160)kV.In field of the aluminum casting, the two equations were derived earlier proved their capabilities as a right method for identification each of size and depth of such defects in castings and welded joints

دراسة تحضير مادة كاؤلين دويخله كمالات في صناعة الورق == A STUDY OF USING KAOLIN DUEKHLA AS FILLER IN THE PAPER INDUSTRY

Author name: علي رزاق عبد الرضا
Supervisor name: ازهار جواد داوود
General topic: Physics
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: يتناول البحث دراسة تاثير خفض نسبة اكاسيد الحديد والتيتانيوم السيليكا الحرة من اطيان كاؤولين دويخله لغرض استخدامها كمالات في صناعه حشوه الورق.لما لهذه المكونات من تاثير على خواص الحشوه. يحتوي خام الكاؤولين المستخدم في هذا البحث على حوالي 1.7% من اوكسيد الحديد و1.2% من اكسيد التيتانيوم و51.16% من اوكسيد السيلكون من ضمنه12% من السيليكا الحرة. ويعتبر وجود هذه النسب من اوكسيد الحديد والتيتانيوم والسيليكا الحره ضمن الخام غير مرغوب في صناعة الورق , لقد اجريت معامله كيميائية لكاؤولين دويخله بهدف تنقيته من الشوائب التي يمكن ان تذوب بحامض الهيدروكلوريك حيث ثم الاستمرار بغسل الكاؤولين بالماء المقطر لتصل درجةpH الى قيمة خمسة . ثم تجفيفه لمدة 3 ساعات بدرجة حرارة من (40 - 60) م0 وبعدها تم طحن المسحوق بالمطحنة البورسلينيه لمدة 5 ساعات. ثم نخل المسحوق بمنخل ذو حجم حبيبي 65 مايكرون ليتم استخدامه في الدراسة. استخدمت في هذا البحث طريقة الترسيب, وقد اعتمد في طريقة الترسيب على فصل الاكاسيد المذ كوره من الاطيان استخدام ماده مشتته هي فوسفات الصوديوم. كما تم دراسة تاثير الماده المشتتة على لزوجة الخليط حيث تبين ان بزيادة الماده المشتته تقل نسبه اللزوجة الى ان تصل الى اقل قيمه. كما تم دراسة تاثير كبريتات الخارصين المائية كماده قاصرة على نموذج المجموعه M4 وباوزان تراوحت( بين10 الى 22 غم) من الماده القاصرة كخطوه ثانيه لتقليل نسبه الشوائب المذكورة والتي بالنتيجة تؤدي الى زيادة نصوعيه كاؤولين دويخله حيث تم ازالة حوالي 73% من اوكسيد الحديد,91% من اكسيد التيتانيوم, 15% من اوكسيد السيلكون, و50% من السيليكا الحرة في نموذج المجموعه G7. النتائج المستحصله تبين كفاءة هذه الطريقة في فصل الشوائب الغير مرغوب فيها اذ انخفضت نسبة اوكسيد الحديد المتبقي في الماده المعالجه (من 1.71% الى0.3%), واكسيد التيتانيوم ( من1.2% الى 0.09%), واوكسيد السيلكون (من 51.16% الى 39.7%). وكون الطريقة المتبعه في الفصل هي طريقة فيزيائيه فلم يلحظ حدوث تغير في خواص الخام بعد المعالجه, مما يمكنا استخدام الخام المعالج بهذه الطريقه في صناعات اخرى. | This study is carried out to investigate the possibility of using Iraqi clay; Duekhla kaolin as filler in the paper industry by reducing the percentage of iron oxide, titanium dioxide, and free silica. Duekhla Kaolin containe about 1.7% iron oxide, 1.2% titanium dioxide, 51.16% silicon dioxide, and 12% free silica. The existence of these oxides in kaolin is undesired in paper - making. The process started by washing Duekhla kaolin with (4N) HCl to remove all the soluble oxides which are not required in paper making. The washed kaolin then separated using filter papers and under a sequence of operations of dilution and filtering until the pH - value become 5. The separated materials then dried at temperature range 40 - 60 °C for 3 hours, and the dried powders then milled using ball mill of porcelain body, with different sizes of spheres, for 5 hours. Finally the powders of Duekhla Kaolin sieved with a sieve of 65 μm. The sedimentation method is used for the separation of the above mentioned oxides from clay by using sodium phosphate as dispersant agent. The viscosity parameter of the mixture was studied under the effect of the dispersant agent, and it was found that with the increasing of added dispersant agent the viscosity decreased to a minimum value which is equal to 0.31dyne.cm2/sec, after that the viscosity increased with the increasing of adding sodium phosphate. The study performed; depending on the minimum viscosity value corresponds to the dispersant amount added. The zinc hydrosulfite was used as a bleaching agent in a second step for removing the undesired impurities which implies to raise the brightness degree of kaolin Duekhla as a result. As a result of these treatment, the undesired oxides are reduced from sample G7 by the following percentages; (73% of iron oxide, 91% of titanium dioxide, 15% of silicon dioxide, and 50% of free silica removed), the results of this study reveals that the oxides percentages decreased from (1.71% to 0.3% in iron oxide, 1.2% to 0.09% in titanium dioxide, and 51.16% to 39.7% in silicon dioxide). The crystal structure of kaolin did not change after these treatments to decrease the percents of impurities in this clay to be used as filler in the paper industry