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كشف اشعة كاما للنويدات المشعة في انسجة بشرية == GAMMA - RAYS DETECTION OF RADIONUCLIDES IN HUMAN TISSUES

Author name: محمد سعد علي
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: وضعت هذه الدراسة لكشف وحساب الفعالية النوعية للنويدات المشعة في الانسجة البشرية المسرطنة التي تم استئصالها من مرضى مدينة بغداد باستخدام تقنية التحليل الطيفي لاشعة كاما بواسطة كاشف التالق ايوديد الصوديوم المطعم بالثاليوم (2×2 انج).استندت الدراسة الحالية على 26 عينة مصابة و8 عينات سليمة لمقارنة النتائج وقد شملت اربعة انواع من الانسجة الطرية (كلية, قولون, ثدي, رحم) والتي يمكن الحصول عليها بكتل كبيرة. اما عملية جمع العينات فقد تم الحصول عليها من قسم الهستوباثولوجي التابع للمختبرات التعليمية لمستشفى مدينة الطب ومستشفى الجراحات التخصصية.اخذت كل عينة بوزن 250 غم, غسلت بالماء المقطر لتخليصها من سائل الفورمالين (المادة الحافظة), قطعت ثم وضعت في وعاء مارنيلي بشكل منتظم, بعد ذلك فحصت بكاشف ايوديد الصوديوم المطعم بالثاليوم لفترة زمنية مقدارها 4 ساعات (14400 ثانية) وفولتية تشغيل مقدارها 530 فولت.قيست كفاءة الكاشف باستخدام مصدر (152 - uΕ) اما اطياف اشعة كاما لعينات النسيج فقد تم معايرتها وفقا لطيف كل من مصدر (137 - sC) و(60 - oC) و(22 - aN). تم رصد 6 نويدات مشعة في العينات المنتخبة حيث توزعت بين 2 - 5 نويدات في كل عينة وقد شملت : نويدتين (214 - Bi, 214 - bP) عائدتين الى سلسلة اليورانيوم؛ نويدتين (228 - Ac, 208 - lT) عائدتين الى سلسلة الثوريوم؛ نويدة صناعية واحدة (137 - sC)؛ والنويدة الطبيعة (40 - K).تراوحت الفعالية النوعية لليورانيوم الملاحظ (نواتج انحلال 238 - U) في العينات المصابة بين (1.02 - 7.46 بكرل/كغم) اما العينات السليمة فقد تراوحت بين (0.88 - 2.02 بكرل/كغم) وقد تراوحت الفعالية النوعية للثوريوم الملاحظ (نواتج انحلال 232 - Th) في العينات المصابة بين (0.59 - 4.84 بكرل/كغم) اما العينات السليمة فقد تراوحت بين (0.49 - 2.71 بكرل/كغم).رصدت نويدة (137 - sC) في جميع العينات المنتخبة بفعالية نوعية تراوحت بين (0.64 - 6.46 بكرل/كغم) في العينات المصابة اما العينات السليمة فقد تراوحت بين (0.5 - 3.46 بكرل/كغم), اما نويدة (40 - K) فقد ظهرت في جميع العينات المنتخبة ايضا لكن بفعالية نوعية اكبر مقارنة بالنويدات الاخرى حيث تراوحت بين (44.18 - 85.36 بكرل/كغم) في العينات المصابة اما العينات السليمة فقد تراوحت بين (40.62 - 56.95 بكرل/كغم). تشير النتائج الى ظهور نفس النويدات على الاغلب في كلا النماذج المصابة والسليمة لنفس النوع من النسيج لكن بفعالية نوعية اقل في النماذج السليمة. | This study is carried out to detect and measure the specific activities of radionuclides in cancerous samples of human tissues that excised from Baghdad city patients. The measurements were done using spectral analysis technique for gamma - ray with 2"×2" NaI(Tl) scintillation detector.Our present investigations are based on the study of 24 abnormal samples and 8 normal samples for comparing the results. These samples include four types of fresh tissues (kidney, colon, breast, and uterus) that may be obtained with great mass. These samples had been collected from the histopathology department for education laboratories in Madenat Al - Ttib and specialized surgical hospital. Each sample is taken with 250g in weight, washed with distilled water to remove the formalin liquid (conservator substance), cut, put in the Marenilli Beaker uniformly and then examined with NaI(Tl) detector for a period of 4 hours (14400s) and 530 V as an operating voltage.Detector efficiency was measured by using Eu - 152 source while gamma - ray spectra for tissues samples had been calibrated with respect to spectra of Cs - 137, Co - 60 and Na - 22 sources.Six radionuclides have been detected in the selected samples where distributed between (2 - 5) radionuclides in each sample. These radionuclides included : two radionuclides (Bi - 214 and Pb - 214) belonging to the uranium series; two radionuclides (Ac - 228 and Tl - 208) belonging to the thorium series; one artificial radionuclide (Cs - 137); and the natural radionuclide (K - 40).The specific activity of detected U - 238 (U - 238 decay products) ranged between (1.02 - 7.46 Bq/kg) in the abnormal samples and (0.88 - 2.01 Bq/kg) in the normal samples while the specific activity of detected Th - 232 (Th - 232 decay products) ranged between (0.59 - 4.84 Bq/kg) in the abnormal samples and (0.49 - 2.71 Bq/kg) in the normal samples.The artificial radionuclide (Cs - 137) is detected in all samples with specific activity ranged between (0.64 - 6.46 Bq/kg) in the abnormal samples and (0.5 - 3.46 Bq/kg) in the normal samples. The natural radionuclide (K - 40) is detected in all samples too, but with largest specific activity compared with other radionuclides where it ranged between (44.18 - 85.36 Bq/kg) in the abnormal samples and (40.62 - 56.95 Bq/kg) in the normal samples. The results indicate that same radionuclides are often appeared in both normal and abnormal samples for the same type of tissue but with least specific activities in the normal samples.

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
Specific topic: Solid State and Materials Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
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

مسار الالكترون داخل المموج اللولبي لليزر الكترون الحر == The Trajectory of Electron in Free Electron Laser Helical Undulator

Author name: زينة محمود الداغستاني
Supervisor name: محمد عز الدين الصندوق
General topic: Physics
Specific topic: Laser Physics and Electro-optics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: نظرية البعد الواحد استخدمت لدراسة اداء مكبر ليزر الالكترون الحر عندما تملك حزمة الالكترونات توزيع منتظم للكثافة في مسار عمودي على محور المموج اللولبي مع اطوار ابتدائية منتظمة توزع بين فترة (0 - 2π ). لقد تم استخدم برنامج matlab 6.1 في بناء برامج الدراسة.في هذا العمل تمت دراسة لحركة الالكترون داخل المموج اللولبي واستنادا الى معادلات الحركة للالكترون فقد تم التركيز على العوامل الثلاثة التالية : 1 - المجال المغناطيسي2 - فترة المموج3 - عامل لورنتز حيث ان الزيادة في المجال المغناطيسي تؤدي الى الزيادة في نصف قطرمسار الالكترون وكمية السرعة المستعرضة للالكترون وبنفس الوقت تؤدي الى النقصان في كمية السرعة الطولية للالكترون. اما في حالة فترة المموج نلالحظ تكرار الظواهر اعلاه في حالة المجال المغناطيسي مع اختلاف السلوك الموجي للالكترون بسبب اختلاف المعادلات المستخدمة فى هذه الحالة.واخيرا الحالة الثالثة فان الزيادة في عامل لورنتز تؤدي الى النقصان في نصف قطرمسار الالكترون وكمية السرعة المستعرضة للالكترون وفي نفس الوقت تؤدي الى الزيادة في كمية السرعة الطولية للالكترون.الظواهر السابقة تمت مناقشتها حسب قانون حفظ الطاقة داخل المموج اللولبي. كذلك تمت المناقشة لدراسة تاثير طور الالكترون, المجال المغناطيسي للمموج وفترة المموج بوجود المجال الكهربائي للموجة الكهرومغناطيسة الداخلة( مثل موجة الليزر المراد تكبيرها) على كمية واتجاه السرعة الطولية للالكترون. حيث وجد ان هنالك زيادة في كمية السرعة الطولية للالكترون تحت تاثير نفس العوامل سواء ان كان مجال مغناطيسي او فترة المموج في هذه الحالة مقارنة مع الحالة الاولى التى تكون بغياب المجال الكهربائي. | The One - dimension theory is applied to study the performance of free electron laser amplifier when the electron beam have a uniform density distribution in the direction perpendicular to the helical undulator axis with initial phases uniformly distributed along the interval (0 - 2π). The matlab 6.1 program is used to built the computer programs that used in this work. In the present work, the motion of electron are considered inside the helical undulator. The equations of motion for electron inside the undulator, show that three effecting parameters, they are : 1 - Undulator magnetic field2 - Undulator period3 - Lorentz factorThe increase in undulator magnetic field leads to increase in the radius of electron trajectory, and the magnitude of transverse electron velocity and at same time leads to decreasing the magnitude of the longitudinal electron velocity.The above effects of undulator magnetic field be reapted in the case of undulator period. Owing to the differences in the equations that used in this case, it is found differences in waves behavior of electron.At last, the increase in Lorentz factor leads to decreasing in the radius of electron trajectory and magnitude of transverse electron velocity and also causes an increasing in magnitude of the longitudinal electron velocity.The effects above discussed as a result of the law of the conservation of energy inside the undulator.The motion of electron is also considered under the effect of the presence of electric field that may be as an electrical component of electromagnetic wave (laser). As comparing with first case (when there is no electric field), there are increasing in the magnitude of longitudinal electron velocity and a variation in electron energy. Within this case, the effect of the phase of electron, undulator magnetic field and undulator period are studied

تصميم وتحليل العدسه الشيئيه رباعية العناصر للمدى الطيفي (mµ 3.2 - 4.2) == DESIGN AND ANALYSIS OF THE FOUR ELEMENTS OBJECTIVE LENS FOR THE 3.2 - 4.2µm SPECTRAL REGION

Author name: صفاء عبد الستار عودة القيسي
General topic: Physics
Specific topic: Nuclear and Environmental Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: اجري بحث حاسوبي لتصميم منظومه بصريه باربع عدسات شيئيه باستخدام برنامج ZEMAX وكذلك دراسة ملائمة بعض المواد(Si, Ge, AMTIR - 1, KRS - 5, ZnSe) التي تعمل ضمن منطقة الاشعه تحت الحمراء (3.2 - 4.2 μm) لعناصر المنظومه البصريه المصممه. اجريت عملية تحقيق الامثليه لايجاد بعض الخصائص البصريه والموصفات التصحيحيه الاكثر تفضيلا من حيث نمط الحيود وحجم البقعه الصوريه الناتجه وكذلك حجم وشكل المنظومه. ان النتائج الحاسوبيه التي تم الحصول عليهابواسطة برنامج ZEMAX اظهرت امكانية استخدام المواد المذكوره ضمن حدود صفاتها البصريه المتمثله بالابعاد البؤريه والزيوغ الكروي وتوزيع الشده والطاقه نسبة للمنظومه والصور المتكونه عند منطقة التحسس. تم اجراء مقارنه للنتائج مع التي حسبت بواسطة برنامج Visual Basic وظهر توافقا عاليا بينهما. ان مواصفات الانظمه البصريه التي قدمت في البحث الحالي قابل للتنفيذ عمليا. | A computational investigation in the present work has been used to design optical system (Four Elements Objective Lens) to show the suitability of some infrared materials (Si, Ge, AMTIR1, KRS - 5, and ZnSe) for the elements of optical designs with aid of ZEMAX package. Optimization process using merit function has been conducted to determine the must favorable optical properties (diffraction, aberration, size of spot, and size and shape of the system). Such designs have been operated in the middle infrared region of spectrum 3.2 - 4.2 μm. The computations obtained by the ZEMAX package shows the performance of those infrared materials through the parameters, focal length, back focal length, f - number, numerical aperture, field of view, Seidel sum for spherical aberration, intensity distribution and fraction encircled energy of the systems and images projected in the detection area. The results have been compared with those obtained with aid of Visual Basic program where a high degree of agreement has been found. The specifications of the optical systems that have been put forward in present investigation can be practically realized

دراسة ثابت الحجب النووي المغناطيسي للعدد الذري من 2 الى 10 == A Study for Nuclear Magnetic Shielding Constant for Z = 2 to 10

Author name: وسام احمد امين المشهداني
Supervisor name: خليل هادي البياتي
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science
Language: English
University location: Baghdad
First pages:

تاثير اعادة الاعتيان والتكميم على ضغط البيانات الصوتية الرقمية == Effect of Resampling and Requantization on the Compression of Digital Audio Data

Author name: شيرين عبد القادر مهدي السامرائي
Supervisor name: لؤي ادور جورج | ليث عبد العزيز العاني
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: ان دراسة اعادة الاعتيان والتكميم للبيانات الصوتية الرقمية تعتبر من المواضيع المهمة حيث تستخدم لاغراض ضغط البيانات.في هذا البحث تم دراسة بعض طرق اعادة الاعتيان بواسطة تقليل عدد العينات مع الحفاظ على نوعية الصوت. ومن هذه الطرق المدروسة : Linear, Lagrange , Cubic Spline , quadratic, and Bezier’’وتم بحث معدل تقليل العينات بواسطة حذف جزء كبير من العينات ومن ثم اعادة العينات التي تم حذفها بواسطة طرق الاستكمال التي تم الاشارة اليها وتم تحديد درجة كفاءة كل طريقة من الطرق المدروسة باستخدام مقاييس معيارية منها نسبة تقييس الاشارة العظمى الى الضوضاء (Peak Signal to Noise Ratio)واثبتت طرق النتائج . كذلك تم في هذا البحث دراسة اعادة التكميم بواسطة الطريقة المتجانسة وغير المتجانسة وتم دراسة مراحل التكميم لكل طريقة مع الحفاظ على نوعية الصوت وكانت نتائج التكميم للطريقة المتجانسة افضل من الطريقة الغير متجانسة.بالاضافة الى ذلك فقد تم اختبار النتائج سمعيا وكانت عينة المستمعين من خلفيات مختلفة وتم استنتاج انه كلمزااد معدل تقليل البيانات ومراحل التكميم سوف تقل نوعية الصوت. | The study of the resampling and requantization methods of digital audio data is one of the major assets project. Which these methods used to compression the audio data. In this search the application of some resampling methods on the audio signal was investigated by reducing the number of samples while the audio quality is maintained. The considered resampling methods are the Linear, Quadratic, Cubic spline, Lagrange and Bezierand for each method the level of sampling reduction was investigated by applying the down sampling rate using and then up sampling using the above mentioned interpolation method. The efficiency of each method under consideration will be determined with the aid of quality criteria like peak signal to noise ratio (PSNR). The Lagrange, Cubic spline, and Beizer interpolation methods provided have the same results and good quality. Also in this search the results of applying the uniform and non - uniform quantization methods are presented the effect of the quantization steps on the audio quality investigated. The results proved the uniform quantization method is better than non - uniform quantization method.A listening test was used to prove the efficiency of each method, the test sample has different backgrounds and they prove when the decimation rate and the step of quantization increase the audio quality will be decrease

ترميم الصور الرقمية باستخدام خوارزمية المرشح التكراري == Restoration of Digital Images Using an Iterative Tikhonov - Miller Filter

Author name: هاله كاظم حسن
Supervisor name: اياد عبد العزيز العاني
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: لقد تم تطبيق المعالجات الصورية في العديد من المجالات العلمية كعلوم الفيزياء والحاسوب والهندسة والكيمياء والبيولوجيا والطب. من المعروف ان عملية الحصول على الصورة باستخدام الطرق البصرية او الالكترونية والتي عادة ما تكون معرضة للتشويه من قبل بيئة المتحسس. مجال ترميم الصورة هو احدى مجالات معالجة الصورة الرقمية الذي يهتم بتحسين الصورة المشوهة. ترميم الصورة ممكن ان يكون خطي او غير خطي واعمى او غير اعمى. تم التركيز في هذا البحث على ترميم الصور الخطي والغير اعمى وفرض ان موديل تشوية الصورة هو عبارة عن التفاف داله الغشاوة بالصورة الاصلية واتلفت باضافة ضوضاء جمعية وان خوارزمية ترميم الصورة هي محاولة للتخلص من داله الغشاوة والضوضاء من الصورة المشوهة بفك التفاف دالة التشويه بالصورة المشوهة وتقليل الضوضاء لانتاج صورة مقدرة قريبة من الصورة الاصلية . الصور المستخدمة شوهت بواسطة دالة غشاوة كاوسية مختلفة الانحراف المعياري σ =1,2 وضوضاء كاوسية جمعية مختلفة بنسبة الاشارة الى الضوضاء SNR= 5,10, 20. التشوية استخدم لعدة انواع من الصور وهي الصورة الرمادية (صورة الستلايت )وصورة السونار (صورة الجنين) والصورة الملونة (صورة الطائر). وينر فلتر وفلتر ميلر - تكنهوف التكراري استخدمت لترميم الصور المشوهة. بواسطة مقياس جذر معدل مربع الخطاء لقد استنتجنا ان افضل اداء لوينر فلتر هو عندما يكون التشويه عالي اي ان نسبة الاشارة الى الضوضاء قليلة وافضل اداء لميلر - تكنهوف التكراري هو عندما يكون التشويه قليل اي ان نسبة الاشارة الى الضوضاء عالية. | Digital images are applied in various fields such us : physics, computer, engineering, chemistry, biology and medication sciences. It have been known that any images acquired by optical or electronic means is likely to be degraded by the sensing environment. Image restoration, is one of digital image processing field, which is care about improving the degraded image. Image restoration may be linear or non - linear and blind or non - blind. The following research focusing on linear non - blind image restoration and assuming that the degradation model as a convolution of the original image with blurring function and distorded by additive noise. Image restoration algorithms are trying to "undo" the blurring function and the noise from the degraded image by deconvolving the blurring function and reducing the noise from the degraded image to produce an estimate image, which it approach to the original image. The image have been used, blurred by Gaussian blurring function with selected standard deviation values σ = 1,2 and degraded by additive Gaussian noise with selected signal to noise ratio values SNR= 5, 10 and 20. The degradation have been used for three type of images, these are gray image (Satellite image), sonar image (Embryo image) and color image (bird image). Iterative Tikhonov - Miller filter and Wiener filter have been used to restore the degraded images. Using Root Mean Square Error (RMSE) measuring it have been concluded that, Iterative Tikhonov - Miller filter has better performance for less degradation parameters, with high SNR and Wiener filter has better performance for more degradation parameters, with low SNR.

دراسة الخصائص الطيفية لسلاسل نظائر نوى الهافنيوم والتنكستن باستخدام IBM وIBFM == Study of Spectroscopic Properties in Isotopic Chain of Hf and W Nuclei Using IBM and IBFM

Author name: عمار عبد الستار زغير الراوي
Supervisor name: سعد ناجي عبود | ليث عبد العزيز العاني
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: تم استخدام نموذج البوزونات المتفاعلة IBM لدراسة التركيب النووي لنظائر الهافنيوم 172 - 180Hf والتنكستن 180 - 190W حيث تم تحديد قيم معلمات معادلة الطاقة الهاملتونية H في نموذج البوزونات المتفاعة الاول IBM - 1 ونموذج البوزونات المتفاعة الثاني IBM - 2 لكل نظير من نظائر الهافنيوم والتنكستن عن طريق المواؤمة (fitting) مع مستويات الطاقة التجريبية المتوفرة. وكذلك تم استخدام هذه المعلمات لكل نظير لدراسة الانتقالات الكهربائية رباعية القطب B(E2) والانتقالات ثنائية القطب المغناطيسي B(M1) والعزوم رباعية القطب الكهربائي للمستويات المتهيجة الاولى Q(2_1^+) والثانية Q(2_2^+) وكذلك نسب الخلط بين الانتقالات الكهرومغناطيسية (E2/M1) والانتقالات احادية القطب الكهربائية B(E0) بالاضافة الى دراسة الازاحات الايزوميرية وازاحة النظائر، وتمت مقارنة النتائج النظرية (بنتائج IBM - 1 وIBM - 2 ) مع القيم العملية المتوفرة وكان هناك توافق جيد بينهما. تم دراسة المستويات المزدوجة التناظر ذات البرم العالي في IBM - 2 بالنسبة لتفاعل ماجيرونا ومنها مستويات ايريست ومستويات ايرير، حيث هذه المستويات تتميز بانها ذات طاقة عالية وE2 ضعيف مع انتقال M1 قوي مع تحديد البرمF (F - Spin) لكل مستوي.المستويات هي المستويات المزدوجة التناظر في نظائر Hf وW وهي المستويات التي تتميز بانها مستويات ذات فونون واحد او فونونين في سلاسل النظائر ذات الشكل γ - softالتي لها اعداد نيوترونية N قريبة من العدد السحري 82 باتجاه النظائر المشوهه نحو منصف القشرة.تم مناقشة مستويات الطاقة B(E2)، B(M1) والمستويات المزدوجة التناظر وتاثير عوامل ماجيرونا على مستويات الطاقة المتهيجة العليا لنظائر 180 - 190W باستخدام IBM - 2. وكان لتغير هذه العوامل تاثير كبير على خواص المستويات المزدوجة التناظر، تم مقارنة جميع النتائج التي حصلنا عليها مع القيم العملية المتوفرة وحصلنا على مقاربة جيدة.حيث وجد ان المستوي في 180W و182W هو اول مستوي مزدوج التناظر بينما في184W و186W هو اول المستويات المزدوجة التناظر في هاتين النواتين. تم حساب خصائص B(M1) ونسب الخلط وكذلك العوامل g - factors وM1 strength للنوى الزوجية للتنكستن 180 - 188W باستخدام IBM - 2.نظائر الهافنيوم (Z=72) تقع في المنطقة المشوهه بينما نظائر التنكستن (Z = 74) تقع في المنطقة الانتقالية باتجاه المنطقة المشوهة العليا. نسبة الخلط E2/Ml لبعض الانتقالات في نظائر172 - 180Hf و180 - 188Wتم حسابها لمستويات الطاقة المنخفضة الموقع وكذلك المستويات العليا (المزدوج التنافر) ومن قيم نسبة الخلط بعضها مقارب للبعض الاخر ومختلف عن القيم العملية بالاشارة وهي حساسة لقيم M1. وهنا تم الاعتماد على طرق جديدة في حساب الشحنات المؤثرة للبوزونات (e_π,e_v )وذلك لغرض استخدامها في حساب الانتقالات الكهربائية رباعية القطب. وكذلك الاعتماد على طرق جديدة وحديثة باتخاذ g - factor لحساب الانتقالات المغناطيسية M1.تم حساب طاقة فصل بوزترون من نوع نيوترون بالاعتماد على برامج متقدمة وجديدة ضمن برنامج NPBOS وكذلك حساب نسبة التفرع X(E0/E2) لكلا السلسلتين.الجزء الاخر من الدراسة تم تحليل مستويات الطاقة الموجبة ومستويات الطاقة السالبة لنظائر الهافينيوم والتنكستن الزوجية الفردية باستخدام نموذجي تفاعل البوزون - الفيرميون الاول(IBFM - 1) والثاني (IBFM - 2)، حيث تم ايجاد مستويات او مدارات الجسم المنفرد ذات التناظر السالب والموجب . وهنا تم استخدام برنامج ODDA وبرنامج PBEFM لحساب مستويات الطاقة والانتقالات الكهرومغناطيسية ونسب الخلط بينهما وتمت مقارنة النتائج النظرية مع القيم العملية المتوفرة.وكذلك تم اعتماد طرق جديدة في حساب الشحنة الفعالة للفرميون (e_F ) وكذلك حساب العامل الجيرومغناطيسي للفيرميون (g_F ) والذين استخدمناهما في دراسة الانتقالات الكهرومغناطيسية في نوى الهافنيوم والتنكستن الزوجية والفردية باستخدام (IBFM) | The interacting boson model (IBM) has been used to make a schematic study of (172 - 180Hf and 180 - 190W) isotopes. For each isotope of Hafnium and Tungsten determined the values of the parameters in the Hamiltonian of IBM - 1 and IBM - 2, which satisfied the best fit to the experimental data for energy levels. Beside on these values, can extrapolate to isotopes are extrapolated for which no experimental data founded and can make predictions for future experiments. We obtain the electromagnetic transition probability B (E2) and B (M1) by using the same values of these parameters for each isotope to, quadrupole moments for first and second excited states, mixing ratios and monopole transition probabilities B (E0), isomer and isotopic shifts and two neutron boson separation energy. Where our results had good agreement with the experimental data in general, although more experimental data we needed for the nuclear properties. The long range goal is to understand the origin of the IBM - 1 and IBM - 2 parameters in terms of a microscopic theory, such as nuclear shell and Nillson models. Results of schematic calculations are presented in various terms of F - spin symmetry in the Hamiltonian of the IBM - 2. Specific attention is paid to the effect of F - spin symmetry breaking on gamma to ground and gamma to gamma M1 transition in deformed nuclei. A comparison with available magnetic dipole moment transition probability M1 data in deformed nuclei is presented. The constraints implicit by these data on the form of IBM - 2 Hamiltonian in deformed nuclei are discussed. Mixed symmetry states are also studied. It is found that some of the mixed symmetry states with moderate high spins change very fast with respect to Majorana interaction. Under known conditions, they become the yrast state or yrare state. These states are difficult to decay and become very stable. This study suggests that a possible new mode of isomers may exist due to the special nature in their proton and neutron degrees of freedom for these isotopes. The mixed - symmetry and states or at least a fragment of it, have been identified in Hf and W isotopes. This enable us to trace the evolution of the one - phonon and two - phonon states in the even - even Hafnium and Tungsten isotopic chain from the γ - soft nuclei near N = 82 to the deformed nuclei towards mid - shell. In 180 - 190W isotopes, energy levels, B (E2), B (M1) and mixed symmetry states (MSS) have been discussed using IBM - 2. The effects of the Majorana parameters on the energy of the highly excited state have been investigated. The variation of these parameters has a great effect on the properties of MSS. All the calculated results were compared to the available experimental data and a reasonable agreement was achieved. It is found that the in 180W and 182W are the first 2+ mixed symmetry states, while the in 184W and 186W are the first 2+ mixed symmetry states. The B (M1) properties of even 180 - 188W isotopes are investigated in the IBM - 2. The (E2/M1) mixing ratios, g - factors, and summed M1 strength are calculated. A least - squares fit of the excitation energies is used to fix the IBM - 1 projected Hamiltonian parameters, while the F - spin - breaking terms are adjusted to reproduce the M1 properties of low - lying states. The influence of F - spin mixing on the summed M1 strength is studied using the coherent state technique in perturbation theory. The M1 properties of the low - lying states are described satisfactorily when the standard boson g factors are used, but the summed M1 strengths are found to be larger than the present experimental values. Possible g factor adjustment, which reconciles the calculated and experimental M1 strength, is discussed. The Hafnium (Z=72) lies in the deformed region and tungsten isotopes (Z = 74) lie in the transitional region that occurs at the upper limit of the range of the deformed nuclei. The - ray E2/Ml mixing ratios for the selected transitions in 172 - 180Hf and 180 - 188W are calculated in the IBM - 2. The Majorana parameters are found to have a great effect on the energy of mixed - symmetry states as well as on the sign and magnitude of the E2/M1 mixing ratios of transitions between regular (symmetric) states. The results demonstrate the sensitivity of the sign and magnitude of values on particular IBM - 2 parameters. In this study, analyzed the positive and negative parity states of odd Hf and W isotopes within framework IBFM - 1 and IBFM - 2. The results of an IBFM - 1 and IBFM - 2 multilevel calculations of and , single particle orbit are reported for the positive and negative parity states of the odd atomic mass number, A, Hf and W isotopes. Also, an IBM - 1 and IBM - 2 calculation by using ODDA and PBEFM programs is presented for the low - lying states in the even - even 170 - 180Hf and 180 - 190W core nucleus. The energy levels, B (E2) and B (M1) transition probabilities and mixing ratios are calculated and compared to the available experimental data. We found that the calculated positive and negative parity low spin state energy spectra of the odd - A 171 - 179Hf and 181 - 187W isotopes agree quite well with the experimental data.

تخمين الجرعة الاشعاعية للاشعة المؤينة وفوق البنفسجية باستخدام كواشف الاثر النووي == Radiation Dose Assessment for Ionizing and Ultraviolet Radiations Using CR - 39 , Lexan and LR - 115 Nuclear Track Detectors

Author name: فلا حاتم طه
Supervisor name: حسين علي الجبوري
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: The aim of this study is the radiation dose assessment of gamma rays - γ and ultraviolet - UV radiation on nuclear track detector - NTDs types CR - 39 , Lexan and LR - 115 through measuring the absorbance - A by using uv - visible spectroscopy technique and measuring the spectral deviation of Fourier transform infrared - FTIR technique .The radiation response for gamma rays was measured at low dose range 1Gy to 10 Gy and high dose range 10 Gy to 195 kGy .There is gamma ray response for all NTDs used in this study . Results revealed gamma radiation response at low and high radiation doses for Lexan and LR - 115 detector using optical absorbance - A ,while the radiation response for CR - 39 detector appears only at high dose range .The results show that absorbance - A increases with increasing of gamma radiation dose, where it was observed that Lexan detector has a radiation response much better than CR - 39 and LR - 115 detectors through measuring increasing in the absorbance - A value at the wavelength 800 nm . There is deviation in some of wavenumbers - W of FTIR spectrum measured for CR - 39 detector. This deviation appears at low dose range from 1Gy to 10 Gy with increasing of gamma radiation dose at wavenumbers - W 1405 and 1456 cmˉ ˡ , while the deviation does not appear in Lexan and LR - 115 detectors .Also, for uv - irradiation there is an increase in absorbance - A with uv - irradiation in dose at the range from 1 J/cm² to 360J/cm² . LR - 115 detector has uv - radiation response better than CR - 39 and Lexan detectors through measuring the increasing in absorbance - A at the wavelength 650 nm.The deviation in FTIR spectrum caused by uv - irradiation appears at the wavenumbers - W 1338 , 940 and 2907 cmˉˡ for CR - 39 , Lexan and LR - 115 detector respectively. The deviation in CR - 39 and Lexan detectors is more clear than in LR - 115 detector.From the results of this study , a possibility appears for the case of NTDs type CR - 39 , Lexan and LR - 115 as gamma and uv radiation dosimeters in medical and environmental fields.List of

تطور التركيب في نوى الباريوم الزوجية - الزوجية باستخدام نموذج البوزونات المتفاعلة == Structure Evolution in the even - even Ba nuclei with IBM

Author name: غفران عبد علي
Supervisor name: سعد ناجي عبود
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: The nuclear structure and electromagnetic transitions of even - even neutronrich 120 - 148Ba isotopes was studied in the framework of the collective models Interacting Boson Model (IBM - 1 and IBM - 2) and Dynamic Deformation Model (DDM). The reduced transition probabilities B(E2), B(M1), monopole matrix element  (E0) , mixing ratio  (E2/M1) and X(E0/ E2) of these isotopes was calculated. A set of parameters was used in the calculation to approach the values with the measured data. It was pointed out that Interacting Boson Model (IBM - 1 and IBM - 2) are equitably reliable for the description of spectra and other nuclear properties. It was found that there is a rapid transition between spherical and rotational shapes. In this work, we depend on new methods to evaluate the effective charges for proton and neutron boson ( )  e and ( )  e , and new method to calculate the gyromagnetic ratio for proton boson ( )  g and ( )  g .Mixed symmetry states are also studied. It is found that some of the mixed symmetry states with moderate high spins change very fast with respect to the Majorana interaction. Under certain conditions, they become the yrast state or yrare state. These states are difficult to decay and become very stable. This study suggests that a possible new mode of isomers may exist due to the special nature in their proton and neutron degrees of freedom for these isotopes. The mixed - symmetry 2 , 3  2 , 4    1 3 and 1 ,  states or at least a fragment of it have been identified in Ba isotopes. This enables us to trace the evolution of the onephonon and two - phonon states in the even - even barium isotopic chain from the γ - soft nuclei near N = 82 to the deformed nuclei towards mid - shell. The Dynamic Deformation Model (DDM) of Kumar and Baranger is employed for studying variations of the nuclear structure of light 120 - 140Ba isotopes. The potential energy surface parameters have been calculated and the low - lyingn levels spectrum is predicted along with the static and transition E2 moments.Comparison with experiment data and with other theories supports the validity of our treatment.The recent developments of the dynamic deformation model (DDM) make it readily applicable to a wide range of nuclei in periodic table. We study of the even - mass barium isotopes from N= 64 to the closed neutron shell at N= 84. Within this region there is experimental evidence for nuclei with the characteristics of vibrational, rotational or  soft level sequences. We show that the DDM model is well able to account for these features as typified by energy levels, electric quadrupole moments and gamma transition probabilities across this region when the only parameter which changes is the neutron number. For comparison the experimental data were also fitted to IBM - 2 and the results from these fits are in general in good agreement with those from the DDM.Supervisor Certification We certify that this thesis entitled ''Structure Evolution in the even - even Ba nuclei with IBM'' was prepared under our supervision at the University of Al - Nahrain Collage of Science Department of Physics, in partial fulfillment of the requirements for the degree of Master of science in physics.

تحضير المركباث الجديدة Sn - 1223 وCu - 1223 الفائقت التوصيل العالي من Hg - 1223 == Preparation of Novel High Temperature Superconductor Compounds (Cu - 1223 and Sn - 1223) From Hg - 1223

Author name: اسراء ماهر جمال
Supervisor name: عماد خضير الشكرجي
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: The main problem is the replacing of Hg atom by covalent atoms such as(Cu,Sn) atoms in the compound ((H )B C C ) by consider (x=0 - 1). Firstly, the high temperature superconductor of (HgB C C ) Hg - 1223 had been synthesized experimentally by solid state reaction. The high temperature superconductor (CuB C C ) Cu - 1223, (SnB C C ) Sn - 1223 had been synthesized by solid state reaction.There are many parameters affected the preparation technique such as flow of oxygen, sintering temperature and compacted pressure. The ceramic samplesof((HgB C C ),(CuB C C ) and (SnB C C ) was analyzed by XRD technique to show the phase of Hg - 1223. The XRD - pattern exhibited the presence of Hg - 1223, Cu - 1223 and Sn - 1223 like tetragonal phase incomparable with the ASTM data sheet.The analysis of XRD - pattern showed that the high phase Hg - 1223 was predominated in the crystal structure of all compound (CuB C C ) and (SnB C C ). The XRD - pattern with the aid of a computer software to determine the lattice parameters. The lattice parameters for Hg - 1223 were a=3.99 , b=3.99 and c=16.47 , the compound Cu - 1223 had a=4.171 , b=4.171 and c=16.743 and the compound Sn - 1223 had a=4.05 , b=4.05 and c=15.682 .The EDX analysis for all compounds was investigated to show the elemental ratio in the mixture in agreement with the applied concentration of elements. The SEM analysis for all ceramic samples were showed the surface morphology and then the nature of grains and their size. The Iodiometric Titration Method also had been used to show the oxygen excess that was the role to enhance the mechanism of superconductivity.The resistivity measurement plays an important role in proving the predominate phase and the superconductor behavior through the presence ofIXcritical temperature which was about 115 K, 128 K and 110 K for superconductor compounds Hg - 1223, Cu - 1223 and Sn - 1223 respectively. In order to remove the low phase Cu - 1212 appearance in the crystal structure of the high temperature superconductor compound Cu - 1223 and to improve the superconductor properties we repeated the sintering process. As a result the XRD analysis indicated that the low phase Cu - 1212 predominated in the crystal structure which was had tetragonal phase with the lattice parameters a=3.55 , b=3.55 and c=12.37 . The resistivity measurement was supported the low phase Cu - 1212 with critical temperature about 64 K.

تصميم وتصنيع غشاء رقيق من اكاسيد الزنك المضاد للانعكاس باستخدام تقنيات مختلفة == Design and Fabrication of Antireflection ZnO Thin Film by Using Different Techniques

Author name: نداء طه ياسين
Supervisor name: علاء جبار غزاي
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: In this work single layer antireflection coating of ZnO thin film has been designed and fabrication on glass and PSi substrates using pulse laser ablation (PLA) and spin coating techniques.Mainly, the work, divided into two parts, first : single antireflection of ZnO thin film using modified characteristics matrix to satisfy zero reflection condition theoretically. Second : ZnO nanoparticle deposited on different substrates using PLA which including the effect of duration pulse of 1000, 1500, 2000 pulses, Energy of 600, 700, 800 mJ and type of solvent by methanol and distilled water have been fabricated studied. In addition, spin coating method have been employed to synthesis this film. Structural and optical properties of prepared films have been characterized using XRD, SEM and EDX, and UV - Vis, respectively.XRD results revealed that the ZnO thin film have hexagonal structure with polycrystalline in nature with preferred orientation of (002). In addition, crystalline size was increased with the increasing of duration pulses at methanol solvent at fixed energy of 700 mJ, besides; in distilled water solvent at 700 mJ have low crystalline size at duration pulse of 1500 pulse. While at fixed duration of 1500 pulse, the crystalline size has low valne at energy of 700 mJ . As well as, the film deposited on glass and PSi substrate using sol gel method have crystalline size of (96.83and 85.16) nm respectively. Narrow FWHM and no phase change has been observed in all cases. SEM images showed that for all cases the films were homogenous with some island and cluster then cracking started to obtain with the increasing of increase the pulse number. Expected of film on glass prepared using

بناء وتوصيف BNT - BKT - BT البيزوالكترك لخزن الطاقة == Construction and Characterization of BNT - BKT - BT Piezoelectrics for Energy Harvesting

Author name: نذير بشير محمود
Supervisor name: عماد خضير الشكرجي
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: Lead - free piezoelectrics are non - toxic, cheap and environmental friendlymaterials. Among them Bismuth Sodium Titanate (BNT) which has thechemical formula Bi0.5Na0.5TiO3 with a complex A - site perovskite structure. Inthis study, some modifications on BNT were used to help in applications byforming solid solution with Bi0.5K0.5TiO3 (BKT) and BaTiO3 (BT). The BNTbased(xBNT - yBKT - zBT) with x+y+z=1 ; were prepared via different methodsat the Morphotropic Phase Boundary (MPB) : 0.94BNT - 0.06BT , 0.93BNT - 0.07BT , 0.8BNT - 0.2BKT, 0.84BNT - 0.16BKT and 0.9BNT - 0.065BKT - 0.035BKT with their origin BNT , BKT and BT. Mini Database was proposeddepending on the results of international databases and some crystallographysoftware and plotted as phase diagrams. Several predictions were suggesteddepending on the built Mini Database and phase diagrams for the BNT - BKTBTsystem. The main prediction was : the physical properties either dependedon the changing of crystal structure ( polarization , dielectric constant ,piezoelectric coefficient ) or the properties had linearity with the composition (density, melting point , sintering temperature ). It has been focused on thestudying the crystal structure, dielectric measurements, hysteresis loopmeasurements and polarization fatigue analyses for ceramic samples.The samples were prepared by different methods : the hydrothermalmethod with spherical shape particles of 65nm - 600nm size; and by solid statereaction method. The powder were pressed in suitable template at 250MPa ,sintered according to database prediction "sintering temperature phase diagram", the resulted ceramic discs had relative density 90% - 96 %. These results agreed with the database predictions "sintering and density phase diagrams”.The crystal structure for the prepared samples were studied using X - ray diffraction (XRD) analysis, the XRD showed that the samples BNT - 6BT, BNT - 7BT, BNT - 20BKT, BNT - 16BKT and BNT - BKT - 35BT had the Morphtropic Phase Boundary (MPB) while BNT had the rhombohedral structure. BKT and BT had a tetragonal structure. These results agreed with the predictions "crystal structure phase diagram" The dielectric measurements showed that there were three regions for BNT - BKT - BT system; the first one was the samples with relaxor ferroelectric behaviors, the samples belonging to this region were BNT, BNT - 6BT, BNT - 7BT, BNT - 20BKT, BNT - 16BKT and BNT - BKT - 35BT (i.e. BNT and the MPB region). The second region was the samples with Normal ferroelectric behavior.The sample with this region was BT. The third region was the samples with relaxor - like ferroelectric behavior (weak ferroelectric) as in BKT. The Curie temperature for the samples within MPB was between 270℃ to 300℃, while for the origin : for BNT the Curie temperature was about 320℃; for BKT was about 370℃; and for BT was about 110℃. The depolarization temperature for samples within MPB region was below 100℃ (above room temperature) while for BNT was 250℃.The hysteresis loop measurements were studied both experimentally and theoretically. The study showed that the results for BNT were Ps=35μC/cm2, Ec=60kV/cm, for BKT was Ps=30μC/cm2, Ec=4.7kV/cm and for BT was Ps=26μC/cm2, Ec=9.8kV/cm, while for the samples within the MPB region the results were Ps=45μC/cm2, Ec ≈ 30kV/cm. The polarization had the largest value within MPB, which agreed with the first prediction by the proposed database (i.e. the polarization of BNT - BKT - BT system depends on crystal structure). The coercive electric (Ec) had a linear behavior with the composition. The value of Ec within MPB was in the range of 27kV/cm to 33kV/cm, which was half of the value for pure BNT. This result agreed with the second prediction by thedesigned database. The polarization fatigue analyses were performed depending on the fatigue model. The results showed that the polarization life cycle had the values of 1012 cycles for BNT, 1011 cycles for BT and 104 cycles for BKT, while within MPB region the polarization life had the largest value of about 1016 cycles which was much greater than in origin (BNT, BKT and BT). This result also agreed with the first prediction by the designed database (polarization life cycle had the largest value and depends on the crystal structure). The fatigue analyses predicted the value of applied electric field used in hysteresis loop measurements and the effect of cycle on the applied electric field.Finally, some of the problems were skipped and properties of BNT were enhanced by looking for the MPB region in the solid solution. The MPB showed the value for polarization to be larger than that in pure BNT, and it reduced the coercive electric field comparing to the original BNT. The polarization life cycle at MPB was much greater than in BNT. Therefore, this study could find some solutions for the drawbacks of BNT, and solve some problems for other piezoelectrics.

دراسة عامل تراكم الجرعة لاشعة كاما في الماء والكرافايت ضمن مدى الطاقة (10 - 4) م. ا. ف == A Study of Gamma Ray Dose Buildup Factors in Water and Graphite, in the Energy Range (4 - 10) MeV

Author name: حنان محمد جواد
Supervisor name: ليث عبد العزيز العاني
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: لقد اجريت دراسات عديدة لقياس عامل التراكم لاشعة كاما بانواعه المتعددة لما له من اهمية في قياس الجرع الناتجة من استخدام الاشعة الكهرومغناطيسية وفي تدريعها. في هذه الدراسة تم حساب عامل تراكم اشعة كاما لاثنين من مواد التدريع (الماء والكرافيت) ضمن مدى الطاقة (4 - 10) مليون الكترون فولط، ولغاية سمك 5 معدل مسار حر, لتحقيق هذه الدراسة تم كتابة وتنفيذ برنامج محاكاة باستخدام لغة Visual Basic language اصدار Gوتطبيقه اعتمادا على اسلوب محاكاة مونتي كارلو.الفكرة الاساسية للبرنامج تشمل وصف السلوك الحقيقي للاشعاع والتنبؤ بحركتة العشوائية خلال الوسط. يمكن استخدام هذا الاسلوب لمحاكاة المسالة التقليدية (الكلاسيكية) الناتجة عن سقوط الاشعاع على شريحة مسطحة تعمل كموهن لاشعة كاما. الشكل الهندسي للمصدر المشع الذي اعتمد في هذه الدراسة هو مصدر مستوى عمودي احادي الطاقة.في هذا البحث تم دراسة عامل تراكم الجرعة لاشعة كاما بوجود وعدم وجود تاثير انتاج الزوج ولنفس الطاقة. كما تم دراسة عدد من المتغيرات المتعلقة بتصميم البرنامج والمسماة متغيرات المحاكاة والتي تتضمن عدد اشعة كاما التي يمكن تتبعها وعدد تقسيم مدى الطاقة. تم دراسة اعتماد عامل التراكم على كل من طاقة الفوتون الساقط, عمق الاختراق والعدد الذري لمادة الدرع في حساب عامل تراكم اشعة كاما اظهرت النتائج ان عامل تراكم الجرعة لاشعة كاما يتناسب عكسيا مع زيادة الطاقة. ويمكن تبرير هذا السلوك بما يلي : عند زيادة الطاقة (ضمن مدى الطاقة المدروس) فان احتمالية استطارة كومبتن تتناقص، لان تاثير كومبتون يتناسب عكسيا مع زيادة طاقة. كذلك فان زيادة الطاقة تؤدي الى زيادة قدرة اختراق اشعة كاما في الوسط وهذا يؤدي الى انخفاض احتمالية الاستطارة بزوايا صغيرة وهذا ينعكس على حساب عامل تراكم الجرعة (حيث انة الاستطارة بزوايا صغيرة لها دور كبير في حساب عامل التراكم ). لكل من الكرافيت والماء، اظهرت النتائج الى ان القيم المحسوبة من عامل تراكم الجرعة لاشعة كاما عند عدم وجود تاثير انتاج الزوج اقل مقارنة عند وجود تاثير انتاج الزوج حيث تبقى مساهمة استطارة كومبتن هي الغالبة مقارنة مع تاثيرالفناء(تاثير انتاج الزوج) ضمن مدى الطاقة (4 - 10) مليون الكترون فولط .النتائج التي تم الحصول عليها بالنسبة للماء من برنامج محاكاة مونتي كارلو في هذه الدراسة كانت قريبة جدا الى بعض النتائج التجريبية المنشورة بالمقارنة مع نتائج محاكاة مونتي كارلو التي تم الحصول عليها من بعض الابحاث المنشورة. حيث تعتبر المقارنة مع النتائج التجريبية افضل وسيلة للحكم على النتائج المستحصلة نظريا. | Several studies have been conducted to measure different type of gamma ray buildup factor for its importance in measuring the dose resulting from Electromagnetic rays use and its shieldingIn this study gamma ray buildup factor for two shielding materials water (Zeff =7.42) and graphite (Z=6) within the energy range 4 - 10 MeV and up to 5 thickness mean free path has been studied. To achieve this study a simulation computer program has been written (Visual Basic language version G) and applied depending on Monte Carlo simulation method. The basic idea of the program includes real radiation behavior description and prediction of its random movement through the media. This method can be used to simulate a traditional problem (classic) resulting from the fall of the beam on the flat slide works as attenuator for gamma rays. The radioactive source geometry adopted in the study is mono energetic normal plane sourceIn this research the contribution of annihilation effect on the calculation of gamma ray dose buildup factor has been studied in the same energy and within the studied energy range. This study also examining a number of variables related to the program design called simulation variables like number of gamma scenarios, number of divisions for energy. This research is also including study the effect of energy for the incident photon, shield thickness, and atomic number for shielding material on the calculation of gamma ray buildup factor. The results indicated that the gamma ray dose buildup factor is inversely proportional with energy increase. This behavior means that when the energy within the studied energy range is increased, the probability of Compton effect decrease, since the Compton effect is inversely proportional with energy. Second, the penetrating ability for gamma radiation is also increase and this leads to an decrease in the probability of scattering with small angels and finally it is reflected on the calculation of dose buildup factor (the scattering with small angels plays a very important role in the calculation of buildup factor). For both graphite and water, although the results indicated that the calculated values of dose buildup for plane source when the contribution of pair production is ignored, less in comparison when the contribution of pair production is taken in consideration but the contribution of Compton effect is still more predominant than the effect of annihilation within the range of energy (4 - 10) MeV.The results obtained from the performed Monte Carlo simulation program in this study are very closer to the published experimental results (error = 10.4%) in comparison with Monte Carlo simulation results (error = 40.58%) obtained from some published researches. The comparison with experimental result is the best way to judge on the accuracy of the results obtains theoretically

تطوير واستخدام منظومه كشف المواد المتفجرة عن بعد == Development and Optimization of Stand off Explosive Material Detection System

Author name: ولدان محمد عواد
Supervisor name: سهى موسى خورشيد الاوسي | كمال حسين لطيف
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: In order to develop a effected method to reveal the presence of explosive, numerous detection techniques have been studied that are capable of detecting explosives, The current study provides an overview of the present techniques like LIBS which is an atomic spectroscopy, and examined a new technique for detecting called laser induced fluorescence (LIF).LIF essentially measures the optical emission of the excited energetic materials by laser. The use of LIF has led to the discovery of unreported optical characteristics of some compounds that are exclusive to the individual material, like the phase shift and the modulation depth of the fluorescence signals.A high resolution spectrometer is used to record the fluorescence emission wave length for three types of explosive materials, These optical characteristics consist of fluorescence shoulders of the three samples in the wave length between (300 - 370) nm .Using fast rise time photo multiplier and spatial amplification for the fluorescence signal enable us to detect the time domain fluorescence spectrum for three types of explosive materials (AN), (TNT),( C4) and other non - explosive material, this method used Carefully for 8m standoff detection, different type of substrate is examined to simulate the real scan, both the time domain and frequency domain is measured for efficient LIF spectroscopy that give us a total configuration of the tested sample.A library of a total time configuration for different type of material s spectrum enables us to develop a algorithms to distinguish between expl osive and non - explosive material. Used to develop a recognition program to achieve high sensitive detection system.

تصميم وتنفيذ متحسس لمعامل الانكسار باستخدام الالياف الضوئية البلورية PCF == DESIGN AND CONSTRUCTION OF REFRACTIVE INDEX SENSOR USING PHOTONIC CRYSTAL FIBER PCF

Author name: مريم عبد الجبار جاسم
Supervisor name: سھى موسى خورشید الاوسي
General topic: Physics
Specific topic: Atomic Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: Photonic crystal fiber (PCF) provides the availability to insert somematerials that enable the materials inside the PCF that provides thematerials to interaction with the light directly where the sensitivity releasedfrom the PCF is higher than the conventional optical fiber. Because of theimportance of the refractive index in many industrial by use it as amonitoring tools, because the clearly relationship between the temperatureand the refractive index and because the clearly sensitive of the phase ofthe liquid - crystals (LCs) where it has a range of temperature to be stay as(LCs) to the temperature and when the temperature be above this range theLCs will be liquid , The aim of the thesis is construction refractive indexsensor using photonic crystal fiber by infiltrating some different materialsof LC such as EBBA (N - (4 - Ethoxybenzylidene) - 4 - n - butylaniline) andMBBA (N - (4 - Methoxybenzylidene) - 4 - n - butylaniline) inside threedifferent kinds of a hollow core PCF (HC - PCFs) like HC - 800 - 02, HC - 1550 - 02, and HC19 - 1550 and using three different laser wavelengthswhich were; 638nm, 850nm, 1550nm. This diversification in the use oftools enable to consider different cases of designed sensor and determine itssensitivity at each case, then one can estimate the perfect cases of thedesigned sensor.It is found that the highest RI sensitivity was 173.31 dBm/RIU forthe HC19 - 1550 infiltrated with the EBBA using the laser with wavelength638nm, while the highest temperature sensitivity was 0.2505 dBm/°C forempty HC - 1550 using the laser with wavelength 1550nm.

دراسة تاثيرات حزمة ليزر هيليوم - نيون واشعة كاما علي المشعع بجسيمات الفا باستعمال بعض CR - كاشف 39 التقنيات المطيافية == Studying the Effects of He - Ne Laser Beam and Gamma Radiation on CR - 39 Detectors Irradiated by ? - particles Using Some Spectroscopy Techniques

Author name: محمد محسن نعمة
Supervisor name: ندى فاضل توفيق
General topic: Physics
Specific topic: Atomic Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: The aim of the present work was to study the effect of alpha - particles, gammarays and (He - Ne) laser beam on the track registration and optical properties of CR - 39 detectors. Twenty - four detectors divided into five groups. First group : include nine detectors were exposed to different powers of (1, 5 and 10 mW) of laser beam at times (5, 10 and 15 min) and then irradiated to alpha - particles from 226Ra source. Then it was measured following track parameters, track diameters - D, track density - ρ, and calculated the bulk etching rate - VB, track etching rate - VT, critical angle - Өc, etching efficiency - η, Sensitivity - S, etching ratio rate - V. The results show there was increased in the values of - D, ρ, VB, VT and Өc with increasing of the exposure times of laser beam at (1, 5 and 10 mW) powers, and decrease in the values of - η, S and V with increasing in the exposure time of laser beam at_1 mW power, while increasing within increase of exposed times of laser beam at (5 and 10 mW) powers. And found the appropriate etching time of CR - 39 track detector at etching time of - 4 h with NaOH etchant solation and - 6.25 N at temperature 60 oC. Second group : includes un - irradiated detector as a control. Third group : include five detectors from CR - 39 detector it was irradiated by gamma radiation from 60Co source with doses (300, 500, 800, 1200 and 1600 kGy). Fourth group : include third groups where it was exposed to laser beam at 10 mW power for 15 min. Fifth group : include nine detectors were exposed to powers - 1, 5 and 10 mW of laser beam at times (5, 10 and 15 min). The optical properties of detector were studied by using the UV - Vis. and FTIR spectroscopy.Where it was calculated the optical energy band gap and number of carbon atom to groups (Second, Third, Fourth and Fifth). The results of ultraviolet spectra show increasing in the absorbance - A of detector with increasing in the time exposure of laser beam at different powers and gamma doses, and also decreasing in the optical energy band gap and increasing in the number of carbon atom with increasing in the exposure time of laser beam at different powers and gamma doses. As for the FTIR spectra show change in the peak position of the bands detector to groups (Third, Fourth and Fifth).

دراسة خصائص انتقال لمتضمنات صوتي - ضوئي عالي السرعة والتردد == Study The Transmission Characteristic of Acousto - Optic Modulators for High Modulator Speed and High Frequency

Author name: لبابة عبد الكریم الجنابي
Supervisor name: سھى موسى خورشید الاوسي
General topic: Physics
Specific topic: Atomic Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: Acousto optics is a science that studying the light and acoustic interaction for purposes of manufacturing modulators and sensors. The technology turned to the use of acousto optic to solve the problem of transforming the communication technology from the traditional one that used the radio signal in coaxial cable into the modern one that uses the laser light in the optical fibers. Also, this enables to overcome the problem of loss and attenuations that occur in the transmission lines using the traditional technology. More sophisticated methods are suggested to help communication researches; one of the most interesting acousto optic applications are the modulators. The modulators are manufactured for specific applications, such that the input energy power and light frequency are taken in to account. The modulator of this application can achieve high accuracy with some co - operation related to the suitability of used material.In the present research, a high speed and high frequency modulator are proposed based on the concept of acousto optic interaction. The occurrence of the interaction requires existence some experimental material arranged in uniform modulator template. The analysis enables to determine the requirements of the proposed modulator design. The newly proposed idea is the use of highly transparent material that absorbed the interference associated with diffraction. Four types of materials are used to test the proposed designed modulator; they are : LiNbO3, SiO2, TeO2, and Ge, the use of such materials offer rich considerable results especially when using different light frequencies to be input into the interaction system. The proposed modulator design is computerized implemented using Comsolsoftware with predefined characteristics are determined in the stage of the analysis and requirements. As a result, different results are obtained for different use of materials and characteristics.The results are examined using validation test, which includes some performance indications. These indications are achieved by two paths : the first is the measurements of operating parameters that obtained by Comsol directly, while the latter is related to computations of efficiency that achieved programming the theoretical relations using MatLab. Actually, the measurements in the first path are documented to ensure the acceptable performance of the proposed designed modulator, whereas the computations of the second path are recorded to ensure the high performance efficiency of the proposed modulator design. In general, the achieved results were matching the state of art given in most advanced literatures, which ensure the validation of the proposed design and correct paths of performance description.The results showed that the proposed modulator design performed the modulation test with an efficiency percent of about 95%, when using LiNbO3 material in the modulator head, and this efficiency is decreases lightly when using other materials. Besides, the employed measurements and computations are nominating the use of LiNbO3 material rather than others to be used in such types of modulators due to its suitable optical features.Frequent practice tests showed that the behavior of the modulator was acceptable and it is enjoying the ability to be improved. The encouraging results gave the opportunity to suggest some developments for future work in order to strength the modulation results.

تحضير التراكيب النانوية للمركب Ba1 - xCaxTiO3 ودراسة الخواص الفيرواليكتريك == Synthesis and Characterization of Ferroelectric Ba1 - xCaxTiO3 Nanoparticles

Author name: عقيل عبد الرضا خضير عباس
Supervisor name: عماد خضير الشكرجي
General topic: Physics
Specific topic: Atomic Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: في هذه الدراسة تم تحضير المركب النانوي تيتانيت الباريوم كالسيوم Ba1 - xCaxTiO3 بقيم مختلفة لعامل التعويض (x) وهي 0, 0.25, 0.5, 0.75, 1. الطريقة المستخدمة في التحضير هي طريقة الهيدروثيرمال الكيميائية والتي تعتبر من الطرق المفضلة لتحضير تراكيب نانوية متبلورة وذات نقاوة عالية. درجة الحرارة المحددة للتحضير كانت 200 درجة مئوية والضغط كان 20 بار.الجسيمات النانوية المحضرة كان لها معدل حجم جسيمي يتراوح بين 20 الى 41 نانومتر. بعد ذلك تم كبس المساحيق بضغط قدره 127 MPa للحصول على اقراص بقطر 1 سنتيمتر. في المرحلة اللاحقة تم اجراء عملية التلبيد لهذه الاقراص بدرجة حرارة 900 درجة مئوية ولمدة اربع ساعات. معاملات التركيب البلوري والمجموعة الفراغية ومعاملات الشبيكة والحجم الجسيمي والحجم الحبيبي تم الحصول عليها من التحليلات التركيبية والشكلية مثل حيود الاشعة السينية والمجهر الالكتروني النافذ ومجهر التصوير الالكتروني. تم استعمال برامجيات خاصة مختلفة في تحليل النتائج مثل حيود الاشعة السينية والمجهر الالكتروني النافذ ومقارنتها مع النتائج الموجودة في قواعد البيانات العالمية مثل ICSD .اضهرت نتائج التحليلات اكتساب المادة طورا بلوريا متعدد باستثناء الشرط التعويضي x = 1 حيث وجد انه يميل لامتلاك طور منفرد. تم دراسة الخصائص الكهربائية المتمثلة بالقياسات العزلية الكهربائية للمركب Ba1 - xCaxTiO3 حيث تم اعتماد حالتين في هذه الدراسة, الاولى كانت تتضمن تغيير التردد وتثبيت درجة الحرارة, والثانية بتغيير درجة الحرارة مع تردد ثابت لغرض قياس ثابت العزل الكهربائي r)ɛ) ومعامل الخسارة (D) , وايضا تم قياس درجة حرارة كيوري (TC). لوحظ خلال البحث ارتفاع قياس درجة حرارة كيوري (TC) مع زيادة نسبة محتوى الكالسيوم Ca في المركب. وجد ايضا افضل قيمة لثابت العزل الكهربائي ودرجة حرارة كيوري هي عند الشرط التعويضي x = 0.25, لذلك توجد امكانية لهذه المادة للتطبيق في المتسعات وتطبيقات الانظمة الالكترونية عالية الفولتية | In this study, a nano - compound Ba1 - xCaxTiO3 (BCT) was synthesized with varying substitution x = 0.25, 0.5, 0.75, and 1. The method used for synthesis is the hydrothermal chemical process, which is preferable to produce ultrafine, pure, and crystalline nanostructures. The material was synthesized at 200 ℃ and was 20 bar pressure for 24 hours. Barium acetates, calcium acetates, and titanium tetrachloride were used as starting materials. The synthesized nanoparticles had a range of particle size (20 - 41 nm). The powder was pressed into a pellets at pressure 127 MPa to get a diameter 1 cm and thickness 2 mm. Then, these pellets were sintered at 900 ℃ for 4 hours. The parameters of the crystalline structure, space group, lattice constants, particle size and grain size were obtained from the structural and morphological, and topological analyses (i.e., XRD, TEM, and SEM). Special different software were used for analyzing, and specification of the structural and morphological results so as to make a comparison with international results and databases like ICSD. The nano powders produced has a polycrystalline structure, except at substitution (x=1), which possesses a single phase structure. Dielectric measurements for Ba1 - xCxTiO3 were achieved. Two conditions were considered in the study. The dependence of dielectric constant (ε_r) and dielectric loss (D), on temperature and frequency was measured at constant frequencies and temperatures respectively. The values of Curie temperature (TC) were determined from the dielectric measurements. It is found that the values of Curie temperature were shifted toward higher temperatures as a result of increasing the calcium ratio in the compound. The composition Ba0.75Ca0.25TiO3 (x = 0.25), reported the best results which are related to crystalline phase, morphology, dielectric constant and Curie temperature relatively, so it is recommended in capacitors and high voltage power electronic applications.

السلوك التلبيدي والخواص العزلية للمتراكب MgAl204 - Al == Sintering behavior and thermal insulating properties of (MgAl204 - Al) spinel composite

Author name: علي حسين صالح
Supervisor name: قاصد عبد الستار صالح الجنابي
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: Spinel - Aluminum composites are drawing greater attention due to their low density, excellent physical, mechanical and refractory properties. This work aims to study the preparing one of the most current conventional technique and sintering behavior of Spinel - Al composite through characterization of the physical, mechanical properties as well as XRD and microstructure of the synthesis Spinel - Al composite specimens.Magnesia (MgO) and alumina (Al2O3) were used as starting materials to prepare stoichiometric magnesium aluminate spinel (MA) via single stage firing process (solid state reaction).Spinel (reinforced material) which prepared at sintering temperatures 12000C and 14000C for 2h soaking time was added in different weight percentage, i.e. 2,4,6,8 wt.% to the aluminum (matrix material) for synthesis Spinel - Al composites in a temperature range of 450 - 6500C via solid state reaction (SSR). The sintering parameters, XRD, microstructure, mechanical and thermal properties of the Spinel - Al composite products were investigated as well as the influence of each of the synthesized spinel contents and sintering temperature on sintering behavior of the composite products were also discussed. The results show that the better sintered density, water absorption, compressive strength, and thermal conductivity of the composite products obtained at low amount addition of spinel fired at 1200 and 14000C was 2wt.% and at 6500C.Also, studying of X - ray diffraction (XRD) for prepared spinel - aluminum composite specimens showed that the composites has many crystalline orientations (38.70, 44.970, 65.30 and 60.190), (390, 45.20, 65.620 and 60.330), (38.90, 45.150, 65.470, and 60.40) and (38.850, 45.260, 65.60 and 60.40) corresponding to (111), (200), (220) and (333) for 2,4,6,8wt% of spinel respectively.The studying of the morphology of spinel - aluminum composite specimens reveal that average grain size of reaches about 6.03, 6.17, 6.22, 6.3 (μm) for 2, 4, 6, 8 wt.% of MgAl2O4 fired at 12000C respectively, whereas their average grain size reaches about 7.18, 7.57, 7.9, 8.48 (μm) for the same spinel content fired at 14000C respectively.

تحضير ودراسة جسيمات الفضة النانوية وتاثيرها المضاد للبكتيريا == Preparing and Studying Nano Silver Particles and Their Anti Bacterial Effect

Author name: سماح صباح عبد الرزاق
Supervisor name: ثامر عبد الجبار جمعة
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: The target of this research is to prepare nano silver particles by laser ablation in both deionized and magnetized water. The properties of nano silver particles and their bacterial effects with different parameters’ were studied. The magnetic water was laboratory preparing by square magnets with magnetic flux of 200 mT applied on the deionized water which pass through it 10ns Q.swiched Nd - YAG laser of wave length 1064nm with different energies and different laser pulses number were used with and without applied electric field. Optical properties for the nano silver colloidal by UV - Vis technique was investigate. The absorption for the silver spectrum was found lied at 420 - 430nm, i.e. involved visible region. The absorption peaks have different height due to different both the shape and concentration of nano silver in the colloidal.TEM technique was used for investigating both size and shape of nano silver particles. The nano silver particles have different shapes such spherical, spindles, etc…. depending upon two parameters is laser energy and laser pulses number. The effect of nano silver particles on bacteria growth of three types of bacteria (staph, ps., E.coli) were studied in details under effect of applied electric field of 3000V/m. There is no inhibition zone was obtained when used different silver colloidal except the colloidal prepared under 600mJ and 1000laser pulses, where this colloidal gives an effected property and ability to determine the bacteria growth type ps. In the range of inhibition of 25nm.The results of the TEM show that the shape of nanoparticles affecting the growth of bacteria was spherical and its size ranges between32 - 50nm.

محاكاة لمتحسس بايولوجي باستعمال الالياف البلورية الفوتونية == Simulation of Biosensor Using Photonic Crystal Fiber

Author name: زينة خليفه حمد الدليمي
Supervisor name: احمد كمال احمد
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: تشكل الياف القلب المجوف والقلب الصلد النوعين الرئيسين من الالياف البلوريه الفوتونيه, ان وجود ثقوب هوائيه في هذه الالياف يساعد على حجز الموجات الكهرومغناطيسيه داخل منطقه القلب كما يساعد في تغيير خصائص الانتشار في الالياف.ان امكانية ملئ هذه الالياف بالسوائل يساعد على تطوير خصائصها البصريه. في هذا البحث تمت دراسة نوعين من الالياف البلوريه الفوتونيه كعناصر تحسس في القياسات الاحيائيه.تم دراسة تاثير حقن الليف البصري بسوائل مختلفه نظريا باستخدام طريقة العناصر المحددة. نفذت عملية حقن الليف المجوف (ماخوذ من القلب 19 خليه) وليف مجوف(ماخوذ من القلب 7 خليه) بسوائل مختلفه ( الماء, الماء الثقيل, بينتانول , دم انسجة الكبد البشريه, دم انسجة القالون البشريه والدم لبشرة الجلد). حسبت خسارة الحبس نظريا باستخدام عدة اطوال موجيه لليف البلوري الفوتوني, وجد ان خسارة الحبس تتناقص تدريجيا للاطوال الموجيه الاصغر كلمزااد معامل انكسار الماده المحقونه. وحسبت قيمة التحسسيه نظريا بالاعتماد على تغير الفقدان في حجز الضوء للنمط الاساسي لليف المحقون بالسائل.وجد ان اعظم حساسيه كانت في مادة الدم لبشرة الجلد وتساوي 674.603 لكل معامل انكسار لنوع وافضل مجال كهربائي وجد لنفس الماده انه يساوي 671 لكل فولت على متر.بينما اعظم حساسيه في نوع وجد انها تساوي 147.201 لكل معامل انكسار لمادة القولون وافضل مجال كهربائي كان في هذه الماده ويساوي 366 لكل فولت على متر. تم اخذ الالياف البلوريه الفوتونيه مصمه باقطار مختلفه وايجاد توجيه الليزر باطوال موجيه تتراوح من (1600 - 600) نانومتر داخل الليف البصري البلوري باستخدام برنامج | Solid and hollow cores comprise two sorts of photonic crystal fibers (PCF). The presences of air holes in PCF serves to both confine electromagnetic waves within the core of the fiber and manipulate its propagation characteristics. the potential of filling the PCF with liquids may improve their optical characteristics. In this thesis, both sorts of PCF were investigated as sensing measurements of biological elements. The impact of liquid filling hollow core PCF was studied theoretically using finite element method. Infiltrated HC19 - 1550 (19 cells are taken from the core) and HC - 1550 (7 cells are taken from the core) PCFs with different liquids (water, heavy water, pentanol, colon tissue, liver tissue and epidermis human skin) were applied. Confinement loss was computed theoretically and found that the confinement loss decreased to shorter wavelengths with increased the refractive index of the liquids. Amplitude sensitivity was computed theoretically by deeming the change in confinement loss for the fundamental mode of liquid filled PCF. The maximum amplitude sensitivity was found to be 674.603 in epidermis blood and the best electric field was found to be 671 V/m in the same liquid for HC19 - 1550, while the maximum sensitivity in HC - 1550 is 147.201 for colon tissue with best electric field found to be 260 V/m also in the colon tissue. Photonic crystal fiber has been taken in different diameters and laser guided by wavelengths from (600 nm - 1600 nm) inside the optical crystal fiber using Comsol multiphysics program

استخدام طريقة للتبع نقطة الطاقة القصوى على اساس الحرارة للسطوح الكهروضوئية باستخدام برنامج PSPICE == Maximum Power Point Tracking approach based on Temperature for PV Surfaces using PSPICE program

Author name: حارث محمد سعيد حامد
Supervisor name: زينب منذر يونس كبة
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: This research study the effect of Photovoltaic surface temperature on Photovoltaic panel output characteristics. First, circuit simulator PSPICE was used to compose Photovoltaic panel model at 75 W, 4.8 A and 21 V. Then, study the behaviorof it under varying conditions (solar insolation, environmental temperature and PV panel surface temperature). ABM feature of PSPICE was used to include the above parameters in PV PSPICE model and produced temperature dependent voltage. The voltageconverted to current with galvanic insolation by element Gploy with gain 0.8. The model defined as hierarichal block in PSPICE library and could be called as individual source for any applications.After studying the effect of PV surface temperature on its (IV) curves specially the position of the maximum power point, this temperature was used to keep tracking of the optimal voltage for the PV panel at the MPP. Therefore DC - DC boost converter was used to achieve this purpose.Boost converter was raise a PV panel voltage from 17 V to 34 V for all variation of surface temperature from 300 K to 350 K at frequency 10 KHz and ΔVo = 5 V.

تاثير المسافة بين الاقطاب ومادة الهدف باستخدام الترذيذ المغناطيسي ذو التيار المستمر == The Effects of Electrodes Separation and Target Material by DC Discharge Magnetron Sputtering

Author name: بان فيصل رشيد
Supervisor name: خالد عباس يحيى
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: تتكون منظومة الترذيذ البلازمي من حجرة تفريغ اسطوانية مصنوعة من مادة (Bolosilicate) وتحتوي على قطبين دائرين من st. st. يحمل الكاثود, مادة الهدف وكذلك المغناطيس الثابت اما قطب الانود فيحمل النماذج الزجاجية التي سوف يتم طلاءها .في هذا البحث استخدمت مادتي الذهب والفضة كمادة لهدف. الهدف من هذه الدراسة, هو دراسة تاثير عوامل التشغيل مثل, المسافة بين القطبين ونوع مادة الهدف على خصائص اشكال سطح زجاجي مطلي بوجود المجال المغناطيسي والتي تمت دراستها باستخدام مجهر القوة الذرية (AFM). وايضا تم تحديد درجه حرارة الالكترون وكثافة الايونات والالكترونات واعلومات البلازما الاخرى بواسطة مجس لانكمور المنفرد عند ضغط ثابت (0.2 mbar).اظهرت نتائج هذه الدراسة بينت وجود زيادة خطية في كثافة الالكترونات والايونات وانخفاض اسي في درجة حرارة الالكترونات عند تغير المسافة بين القطبين ولخمسة قيم و(3,4,4.5,5 and 6)cm لمادتي الذهب والفضة وايضا تبين ان فولتيات التفريغ باستخدام الذهب كهدف هي اكبر منها في حالة الفضة. كذلك, وجد انه بزيادة المسافة بين القطبين فان درجة حرارة الالكترونات تقل لمادتي الذهب والفضة وكثافة الايون تزداد مسببة زيادة في قطر وارتفاع الحبيبة لتيار الترذيذ((I_d=30 mA باستخدام الذهب بينما يقل قطر الحبيبة ويزداد ارتفاعها باستخدام الفضة لتيار الترذيذ( (I_d=40 mA. من ناحيه اخرى, ان قيم درجة حرارة الالكترون باستخدام الفضة هي اكبر من القيم باستخدام الذهب وان علاقة قطر الحبيبة, وارتفاعها وخشونة السطح كدالة للمسافة بين القطبين هي ليست خطية. اصغر قيمة لمعدل قطر الحبيبة وارتفاعهاحصلنا عليه هو(90 nm) وnm)6) على التوالي لمادتي الذهب عند تبار الترذيذ ((I_d=30 mA و( . (d=4 cm وللفضة نفس قيمة قطر الحبيبة باستخدام الذهب عند(d=5 cm) لكن بارتفاع5.5 nm) ) عند (d=4 cm) ولتيار الترذيذ (I_d=40 mA). واصغر معدل ارتفاع للحبيبة لكل تيارات التفريغ 20,30,40,50 and 60 mA)) عند نفس المسافة بين القطبين (d=4 cm) باستخدام الفضة والذهب ولكل تيارات التفريغ ماعدا((〖 I〗_d=50 mA والذي يمثل اكبر معدل ارتفاع للحبيبة فيه باستخدام الذهب. واخيرا, ناتج عملية الترذيذ باستخدام الفضة اكبر مما عليه باستخدام الذهب. | In this work, a DC planner magnetron sputtering system used. Which consists of a cylindrical chamber, made from (Borosilicate). It contains two circular electrodes made from stainless steel. The cathode electrode is carried the target material and permanent magnet while a glass sample, which must coat, is placed on the anode electrode. In this works, gold and silver used as a target materials. The objective of this study is to examine the effects of operating parameters such as, electrodes separation, sputtering current, and type of target materials on the properties of glass surface coated under the influence of magnetic field. The surface morphology for the coated samples are studied by atomic force microscopy (AFM). Furthermore, electron temperature, ion and electron densities and other plasma parameters are determined by a cylindrical single Langmuir probe where the pressure up to(0.2 mbar). It is found that a linear increase in electron and ion densities and an exponential decrease in electron temperature with five values of electrodes separation (3,4,4.5,5 and 6) cm. That was observed for gold and silver target materials. Also, the discharge voltage using gold target is greater than that for silver target. Electron temperature decreased for gold and silver targets as the electrodes separation increased. The ion density increased which caused increasing in average grain diameter, height at sputtering current, Id=30 mA , when the target is gold. However, the average grain diameter is decreased and the height of grain increased at Id=40 mA using silver target. On the other hand, the values of electron temperature using silver target is greater than that for gold target. Also, the relation of average grain diameter, height and roughness surface as a function of electrodes separation are nonlinear. The minimum average values of grain diameter, height are (90 nm) and (6 nm) respectively for using gold at Id =30 mA and d=4 cm. For using silver at Id =40 mA the minimum average grain diameter is also (90 nm) at d=5 cm and height is (5.5 nm) at d=4 cm. For all discharge currents (20,30,40,50 3and 60 )mA , the minimum average grain height at the same electrodes separation d=4 cm for using silver and gold target except the value of Id=50 mA, whom a maximum average grain height is obtained. Finally, the sputtering yield for silver target is greater than that for gold target

تقييم السطح البيني لمنطقة الربط الكرافيت بالمعدن == Evaluation of the Intermediate Layer of Graphite Bonded Metal

Author name: مريم بديع عبود
Supervisor name: ثامر عبد الجبار جمعة
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: This work investigates the joining between graphite and stainless steel grade (410), by using active filler metal paste. Brazing technique was chosen because it is efficient, verstile, fast and economical.These new phases considered enhancement the bonding strength of the assembly.
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