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تاثير بعض المتغيرات الفيزياوية على تصنيع جسيمات الذهب النانوية بواسطة الاستئصال بالليزر وتاثيرها المضاد للبكتريا == The Effect of Some Physical Parameters of Gold Nanoparticles Produced by Laser Ablation on Antibacterial Effect

Author name: مازن كامل حامد
Supervisor name: رعد محمد صالح الحداد | ثامر عبد الجبار جمعة
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

دراسة تركيب نوى Pb, Hg, Te, Cd باستخدام التشكيلات المختلطة لنموذج البوزنات المتفاعلة (IBM-2 CM) == A STRUCTURE STUDY OF Cd, Te, Hg, AND Pb NUCLEI IN THE INTERACTING BOSON MODEL CONFIGURATION MIXING (IBM - 2 CM)

Author name: هنادي حسين شرقي الصميدعي
Supervisor name: سعد ناجي عبود
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تحقيق معاملات بيزوكهربائية - فيروكهربائية للنظام Bi1/2Na1/2TiO3 - Bi1/2K1/2TiO3 - BaTiO3) يستخدم للتطبيقات الالكترونية == INVESTIGATION OF PIEZOELECTRIC-FERROELECTRIC PARAMETERS OF (Bi1/2Na1/2TiO3 - Bi1/2K1/2TiO3 - BaTiO3) SYSTEM FOR ELECTRONIC DEVICES APPLICATION

Author name: اسراء ماهر جمال طاهر
Supervisor name: عماد خضير الشكرجي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تصميم ومحاكاة اجهزة الكشف الضوئية للبنية النانوية البلازمية ثنائية الابعاد باستخدام برنامج Comosol Multiphysics == DESIGN AND SIMULATION OF 2 - D PLASMONIC NANOSTRUCTURE PHOTODETECTORS BY USING COMOSOL MULTIPHYSICS SOFTWARE

Author name: سرور علي مهدي الخفاجي
Supervisor name: سهى موسى خورشيد الاوسي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

دراسة النشاط الاشعاعي البيئي وبعض العناصر الثقيلة في مياه ورواسب نهر دجلة في محافظة بغداد == STUDYING THE ENVIRONMENTAL RADIOACTIVITY AND SOME HEAVY METALS IN WATER AND SEDIMENTS OF TIGRIS RIVER IN BAGHDAD GOVERNORATE

Author name: اكــرم عباس محمـد
Supervisor name: ندى فاضل توفيق
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

حسابات الامثلية لحارف الحزمة الكهروسكوني الرباعي وتاثيراته على اداء حلقة الخزن == A COMPUTATIONAL OPTIMIZATION OF THE ELECTROSTATIC QUADRUPOLE BEAM DEFLECTOR AND ITS EFFECT ON THE PERFORMANCE OF THE STORAGE RING

Author name: جعفر جليل سلطان الطائي
Supervisor name: عدي علي حسين
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تصميم ومحاكاة حلقة التخزين الكهروستاتيكية == DESIGN AND SIMULATION ELECTROSTATIC STORAGE RING

Author name: رؤى عباس حسون
Supervisor name: عدي علي حسين | سهى موسى خورشيد
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تطور مستويات الطاقة المزدوجة التناظر في منطقة العدد الكتلي A=140 [استخدام IBM - 2 == Evolution of the Mixed Symmetry States in the A=140 Mass Region within IBM - 2

Author name: علي ناظم صبار
Supervisor name: سعد ناجي عبود
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تطبيقات المتحسس الغازي لاغشية AlxInyGa1 - x - yN والكاربون ذات التراكيب النانوية == Quaternary AlxInyGa1 - x - yN and Carbon Nanostructured Films for gas Sensing Applications

Author name: غسق علي طعمة
Supervisor name: علاء جبار غزاي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

دراسة الخواص الفيزيائية لمركبات نانوية فائقة التوصيل محضرة بالطرق الكيميائية == Studying the Physical Properties of Nano Structural Superconductor Compounds Prepared by Chemical Process

Author name: زيد خليل ابراهيم
Supervisor name: عماد خضير الشكرجي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تاثير مواصفات الطلاء على اداء المجمع الشمسي == EFFECT OF COATING SPECIFICATIONS ON THE PERFORMANCE OF SOLARCOLLECTOR

Author name: رؤى حميد جاسم
Supervisor name: احمد عبد الرحمن الطباخ
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

قياس تركيز اليورانيوم والعناصر الثقيلة في دم وادرار موظفي وزارة الداخلية العراقية == MEASURENT OF URANIUM AND HEAVY METALS CONCENTRATION IN BLOOD AND URINE SAMPLES FOR EMPLOYESS OF THE IRAQI INTERIOR MINISTRY

Author name: مصطفى سالم محمد
Supervisor name: ندى فاضل توفيق | ليث عبد العزيز العاني
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تقنية التحليل الطيفي للانهيار المحفز بالليزر لفحص تركيب الاسمنت == Laser Induced Breakdown Spectroscopy Technique for Identification Cement Structure

Author name: تغريد خالد حمد
Supervisor name: علاء جبار غزاي | علاء حسين علي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

حسابات هارتري - فوك النسبية لمجموعة 15 الذرية وبعض الجزيئات ثنائية الذرة == Relativistic Hartree-Fock Computations of Group15 Atoms and Some Diatomic Molecules

Author name: بلال خالد جاسم المشهداني
Supervisor name: سعد ناجي عبود | اياد عبد العزيز العاني
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تزامن الشواش في ليزر اشباه الموصلات بطريقة التغذية العكسية لمراة الحلقة البصرية == SYNCHRONIZATION OF CHAOS IN SEMICONDUCTOR LASER BY MEANS OF OPTICAL LOOP MIRROR FEEDBACK

Author name: بان مظفر البياتي
Supervisor name: احمد كمال احمد | قيس عبد الستار النعيمي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

التعرف على قزحية العين باستخدام التحليل المستقل والمكون الرئيسي == IRIS RECOGNITION USING INDEPENDENT AND PRINCIPAL COMPONENT ANALYSIS

Author name: ياسر عدنان جاسم
Supervisor name: ليث عبد العزيز العاني | اياد عبد العزيز العاني
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

متحسسات الالياف الضوئية البلورية : نمذجة وتطبيقات == Photonic Crystal fiber Sensors : Modelong and Applications

Author name: حسين ثامر سلوم الدفاعي
Supervisor name: احمد كمال احمد | عبد الهادي مطشر الجنابي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

حسابات نسبيه لبعض خصائص اطياف الذرات المتوسطة والمرتفعة العدد الذري == RELATIVISTIC COMPUTATION OF SOME SPECTROSCOPIC CHARACTERISTICS OF MEDIUM AND HIGH Z - ATOMS

Author name: عدنان يوسف حسين
Supervisor name: Ra’ad A. Radhi
General topic: Physics
Specific topic: Atomic Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: تم تقديم دراسة منتظمة لطريقة هارتري - فوك غير النسبيه وكذلك نسختها النسبية (ديراك - فوك) لمعدل التوزيع. بالنسبه للطريقة غير النسبية؛ فقد تم اشتقاق معادلات هارتري - فوك وبشكل مفصل واخذ بنظر الاعتبار التصحيح النسبي (تاثير الكتله - السرعه وتاثير دارون وتاثير تفاعل البرم - المداري للاكترون) وقد اعتبر كرتبه اولى للاضطراب. اما بالنسبه للطريقه النسبيه؛ فقد تم اشتقاق معادلات ديراك - فوك واخذ بنظر الاعتبار تاثير تفاعل بريت كتصحيح نسبي للتفاعل الكولومي وقد اعتبر كرتبه اولى للاضطراب. تم تقديم معادلات عناصر المصفوفه لتفاعل بريت (الحد المغناطيسي والحد الارتدادي) لمعدل التوزيع. تم تقديم النتائج لبعض خصائص الذرات في المستوى الارضي(Rb, Zr, Pd, Sn, Cs, Ba, Lu, Ir, Hg, Tl, Bi, Rn ) وتمت مقارنتها بالنتائج العمليه. التاثير النسبي على طاقات الاغلفه الذريه مهم وخصوصا على الاغلفه الداخليه 1s و2s وهذا التاثير يكون محسوسا كلما ارتفع العدد الذري. يكون تاثير بريت حوالي %2 من تاثير التصحيح النسبي (تاثير الكتله - السرعه وتاثير دارون). حسابات هارتري - فوك والتصحيح ال | A systematic study of the non - relativistic Hartree - Fock method and its relativistic version, Dirac - Fock method for the average of configuration have been presented. In the non - relativistic case, a fully derivation of the Hartree - Fock equations were presented and relativistic corrections (mass - velocity, Darwin and spin - orbit terms) are treated as first - order perturbation. For the relativistic case, Dirac - Fock equations were derived, and Breit interaction operator is used as the relativistic correction for the interelectronic Coulomb interaction, and is treated as the first - order perturbation. Expressions for the matrix elements of the Breit interaction operator (magnetic and retardation terms) are given for the average of configuration. Numerical results of some atomic properties for the ground states of (Rb, Zr, Pd, Sn, Cs, Ba, Lu, Ir, Hg, Tl, Bi, Rn ) atoms computed and compared with their corresponding experimental values. The relativistic effect on the orbital energies is important on the inner shells especially for the 1s and 2s shells and this effect becomes more pronounced as Z increases. The contribution of Breit interaction is about 2% of the relativistic shift (mass - velocity and Darwin correction). The Hartree - Fock calculations and relativistic correction gives reasonably good approximation for heavy atoms while Dirac - Fock calculation and Breit interaction gives high precision calculations

تصميم حاسوبي لحزمة ايونية مركزة للمنظومة الليثوغرافية == Computer - Aided - Design Of Focused Ion Beam For a Lithography System

Author name: فاضل عبد العباس علي السهلاني
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: تم بناء تصميم متكامل بمساعدة الحاســــــــوب وباســـتخدام الطرق الامثلـــــــية لمنظومة بصــــرية ايونيــة ، وذلك بدمــــج طريقة البرمجة الديناميكية مــــــع طريقة تقنية الذكاء الاصطناعى.فقد تم الحصول على معامــــــلات الزيوغ النســـــبية الكروية واللونية اســــــــتنادا الى معامـــل الهــــــيـئة للمنظومات البصرية المثلى ، وحســـــــــب الاتى : ا. تصميم عدســـة مفردة ( كهربائية ومغناطيســــية).ب‌. تصميم منظومة بصرية مكونة من عدســتين كهربائيتين.ت‌. تصميم منظومة بصرية مكونة من ثلاث عدسات كهربائيات.ث‌. تصميم منظومة بصرية مختلطة العدسات (كهربائية ومغناطيســــية).كذلك تم تصميم اربعة انواع من العدسات الكهروستاتيكية مع نموذج لعدســة مغناطيســــية لاصــغر زيوغ بصرية ( المرتبة البصرية الاولى والثالثة) ، حيث تم اعادة بناء الاقطاب الكهربائية والمغناطيسية ثم رسمها لبعدين وثلاث ابعاد ببرنامج المحاكاة (SIMION(7 ، وبالاعتماد على قاعدة البيانات المخزونة (قاعدة المعرفة).هذه العدسات هى كما ياتى : • عدســة احادية الجهد (1) فى نمط التباطىء .• عدســة احادية الجهد (2) فى نمط التعجيل .• عدســة مغمــــورة.• عدســة الحاجــــــز.• عدســة مغناطيســــــية (1). تـــــم تصميم وكتابـــة الحزمة البرمجية بلغة الجافا منظومة الخبير (JESS) والبيســــــــك المرئى النســـــخة السادســـة (VB 6) اســتوديو ، وذلك للتحليل والحصول على حسابات الامثلية الكاملة للمنظومة البصرية الايونية.حيث تم تســمية تلك الحزمة CADION .ايضا تم استخدام توزيع الجهد المحورى الامثل لكلا المجالين الكهروستاتيكى والمغناطيسى ، بالاعتماد على الشـــــروط المحددة لبناء وتركيب العمود البصرى المكون من عدســـتين وثلاث عدسات ومختلط العدسات. تـــم حساب حجم البقعة لقياسات النانومتر وتم الحصول على قيم تقترب الى (3.0) نانومتر المســـــــــتخدمة فى تطبيقات تقنية النانومتر. وكذلك تــم اقتراح تعاريف ومفردات لبصريات الجســـيمات المشــــحونة باعتبار بعض النتائج محققة لعلاقة شـــــــبيهة بمدا اللادقـــــة. | A complete computer aided design (CAD) by using optimization methods for the ion optical systems have been developed, by mixing the dynamic programming procedure and artificial intelligence technique. The relative spherical and chromatic aberrations coefficients were obtained according to figure of merit for the following optimized optical systems : a. Single - lens design (electrostatic and magnetic). b. Two - lens system consists of two electrostatic lenses. c. Three - lens system consists of three electrostatic lenses.d. Multi - lens system (electrostatic and magnetic).Four types of electrostatic lenses and a magnetic lens model were designed as small as possible of optical properties (i.e. the first and third optical properties), and reconstructions of electrodes and pole pieces were plotted in two and three dimensions graphics by using SIMION 7.0 simulator depending on the stored database (i.e. knowledge base).These lenses are as follows : • Unipotential lens 1 (operated in deceleration mode).• Unipotential lens 2 (operated in acceleration mode).• Immersion lens.• Diaphragm lens.• Magnetic lens. Present software has been designed and written in Java expert system shell (JESS) and Visual Basic 6 (VB6) for optimizing and analyzing full calculation processes, it has called CADION package. The optimized axial potential distributions for both electrostatic and magnetic fields according to the constraints have been used in the optical column setup, which are two - lens system, three - lens system and multi - lens system. Spot size measurements were calculated in nano scales, which have values closed to (3.0) nm applicable in nano technology applications used in lithographic systems. Also, the present work has been suggested definitions and abbreviations in charged particle optics to be consider some of the results, as a verification of the uncertainty principle relationship like

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.

تعديل سطوح التيتانيوم وسبيكة التيتانيوم باستخدام المواد الاحيائية السيراميكية بواسطة الرشرشة بالترددات الراديوية == Surface Modification of Titanium and Titanium Alloy Using Ceramic Biomaterials by RF Sputtering

Author name: دنيا عبد الصاحب هاشم حمدي
Supervisor name: ثامر عبد الجبار جمعة | ثائر لطيف مزعل
General topic: Physics
Specific topic: Atomic Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: The current in this thesis research deals with the plasma sputtering which was used to deposit single and triple layers ceramics on (cpTi) and ( Ti - 6Al - 4V) alloy. Also ,in this work the in vitro electrochemical tests , formation of HAp by biomimetic process on the coated layers by the immersion in Simulated Body Fluid(SBF) at PH equal to 7.4 and room temperature was done . The single layer TiO2and HAp , multi - layer consist of TiO2 and Al2O3 were deposited on cpTi and Ti - 6Al - 4Valloy, followed by the deposition of third layer of HAp. The deposition conditions in the RF sputtering system such as vacuum pressure, substrate temperature, power, gas type, gas flow and deposition time were fixed for the sputtering system where as the distance between the target and the substrate was varied (9 and 7 cm). Structural analysis was carried out , on the deposited layers(single and triple) using X - ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Furrier Transformation Infra - Red (FTIR), Raman Spectroscopy and X - ray Photoelectron Spectroscopy (XPS). Elemental analysis for HAp deposited in the single and triple layer was done using Energy Dispersive X - ray Spectroscopy (EDS).To investigate the biocompatibility of coatings the formed layers, were immersed in (SBF) for one month. After one month the samples were taken and anlyezed using the same structural analysis techniques used before immersion. Electrochemical investigation was carried out on the deposited layers used Open Circuit Potential (OCP),Linear Sweep Voltage(LSV) and Electrochemical Impedance Spectroscopy(EIS) in SBF. The XRD structural results show that the formation of HAp which was dominated on the phase formation on the surface of the single and triple layers. Also another Calcium - Phosphorus compound phases are found such as Tri Calcium Phosphate(TCP), Octa Calcium Phosphate(OCP) and Calcium Phosphate(CP) along with small fractionIIof the Titanium phase belong the substrate .For TiO2 single layer, XRD pat reins shows the formation of the rutile TiO2which covered the substrate surface.Elemental analysis by using EDS for the single and triple layer deposited in cpTi and Ti - 6Al - 4Valloy shows the energy transitions belong to the dominated elements, Ca and P, which contained in the HAp layer that already showed by XRD. Surface analysis by XPS for immersed samples in SBF for one month show the bonding type and the compound that formed. The XPS results confirmed the SEM observation, the FTIR and Raman results. It was found from the XPS analysis that most of the compound covers the surface are belongs to the Ca - P companies to the carboxyl groups (C - O, C - H) and this was confirmed by the XRD investigation which show the domination of (HAp) in the highest intensity (211) reflection at 2θᵒ of 31.7 for the single and triple layer coating. The XRD results also show the disappearance of the other CaP compounds after one month of immersion in SBF like TCP and CP .The increase in the HAp concentration after immersion indicates the occurrence of the biomimetic process that increases the precipitation of Ca+ and P - from the SBF and the two roots combined together to form CaP compound that increases the HAp concentration. The electrochemical parameters predicted from corrosion test show the improvement in the corrosion resistance of both cpTi and Ti - 6Al - 4Valloy after coated by shifting the OCP toward the nobel direction which was the same behaviour for the corrosion potential Ecorr, and decreases in the corrosion current Icorr and the corrosion rate CR comparing to the uncoated specimens. The (EIS) measurements conformed the improvement in the corrosion parameters result of from OCP and LSV by the very low capacitance for the coated specimens compared to that for the uncoated one which means that the single layer and triple layer protect the surface by increasing the equivalent circuit impedance block

تحضير مادة طلاء من فررايت الليثيوم - النيكل بالتعويض المتكافئ == Preparation of Painting Material from Li - Ni Ferrite with Isovalent Substitution

Author name: صادق هاني لفتة مخلص السراجي
Supervisor name: عماد خضير عباس | علي مطشر موسى
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: حضر فيرايت الليثيوم - نيكل النانوي ذو التركيب Li0.5 - 0.5xNixFe2. - 0.5xO4 بطريقة الهايدروحرارية وبمجموعتين من كلوريدات المعادن وكبريتات الحديدوز وهيدروكسيد الصوديوم. كل مجموعة تتصمن تغيير x بالقبم 0.1 و0.3 وحتى 1.0. المجموعة واحد بدون Fe2+ والمجموعة اثنين مع اضافة Fe2+ . النسبة Fe3+/ Fe2+ ابقيت ثابتة بمقدار 1.7، درجة حرارة التحضير كانت 155oC والدالة الحامضية مساوية لقيمة 11. كل التراكيب حضرت باستثناء المركب عند x=0 بدون اضافة Fe2+ والتي لم يتمكن من تحضيرها بهذه الطريقة تحت الظروف التجريبية المستخدمة. اظهرت النماذج سيادة طور سبنل فيررات بعد x=0.3 للمجموعة واحد وطور نقي عند x=0.3 باستخدام Fe2+ . ثابت الشبيكة للمجموعة اثنين اقل مما للمجموعة واحد. الحجم البلوري يصل لادنى قيمة عند x=0.5 للمجموعة واحد وتقريبا اعظم ما يمكن للمجموعة اثنين عند x=0. قمم اطياف تحت الحمراء لرباعي السطوح تزاح نحو الترددات الاعلى مع زيادة تركيز Ni2+. اشكال الجسيمات كانت : قضبان (غالبا للهمتايت) بمعدل قطر 40nm، وكروية(اصلها مكعبات فيرايت نانوية) بحجم حوالي 20nm. حلقات M - H امتلكت شكل الحرف S مماثلة للتي للسوبربارامغناطيسية. عموما فالنماذج المحضرة تمتلك اقل قاهرية (coercivity)، واعلى تمغنط اشباع (saturation magnetization) من الادبيات المنشورة. كلا المجموعتين امتلكت اعلى تاثرية عند x=0.5. وقد فسرت هذه النتائج على اساس التركيب وتوزيع الايونات الموجبة والتفاعل بينها وحجم الجسيمات. الامتصاص الرنيني للاشعة المايكروية باستخدام اختبار FMR اظهر ان القيمة الاعظم للتاثرية الخيالية χ″ هي عند x=0.5 للمجموعة وقيم عليا عند x=0.7 وx=0.9، واكبر عرض خط حوالي 950G عند x=0.7 . المجموعة الثانية اظهرت اعظم امتصاص(χ″) وعرض خط عندx=0.9 . بعدها تم الخلط مع ايبوكسي النوفالاك بنسبة وزنية 39.7 %. اختبار دائرة القصر - لقياس الرنين المغناطيسي بانعدام المجال قد اظهرت امتصاص للاشعة المايكروية لترددات اكبر من 19GHz. تفسير ان نماذج المجموعة اثنين تمتلك امتصاص اكبر من المجموعة واحد اعتمد على الموصلية التنقلية hopping وعلى تغير المعلمات المغناطيسية ( MsوHc). طريقة خط النفاذ باستخدام VNA في الحزمة - X والحزمة - Ku اظهرت ان خسائر العودة او الانعكاسRL تكون اقل ما يمكن عند x=0.3 للمجموعة واحد في الحزمة - X بينما ذلك عند x=0.3 وx=0.5 للمجموعة اثنين. اضافة Fe2+ يقلل القيمة الدنيا بعامل اكبر من 1.5. خسائر الادراج IL في الحزمة - X تتراوح بين - 4.5dB الى - 7dB . ان RL وIL في الحزمة - Ku تمتلك سلوك متشابه ولكن قيمها اقل. ان RL تصبح اقل ما يمكن عند x=0.5 وبقيمة - 18dB بينما كانت حوالي - 12dB باضافة Fe2+ . ومعدل قيمة IL في حزمة - Ku هي - 6dB. يلخص تاثير السمك بتحسين قيم RL وIL ولكن مع ازاحة القمم الدنــيا الى تــردد اقـل. ســمك بـمقدار 2mm يمـتلك RL< - 27dB وIL< - 19dB. | Nano Li - Ni ferrite samples having the structure Li0.5 - 0.5xNixFe2. - 0.5xO4 were prepared by hydrothermal method in two sets from metal chlorides, ferrous sulfate and NaOH. Each set implicated varying x through 0, 0.1, 0.3 to 1.0. The samples were without and with adding Fe2+. The ratio of Fe3+/ Fe2+ was kept at 1.7. The preparation temperature was 155 °C and pH was equal to 11. All composition was prepared except that for x=0 without Fe2+ which cannot be prepared under used experimental conditions. Samples showed dominant spinel ferrite phase beyond x=0.3 for set one and pure phase at x=0.3 with Fe2+ addition. Lattice constant of set two is slightly lower than set one and both are slightly lower than theoretical values. The crystallite size gets minimum at x=0.5 for set one and roughly maximum at x=0 for set two. Fourier Transformation Infrared (FTIR) spectrums tetrahedral showed peak shift to higher frequency with increasing Ni2+ concentration. Particles shapes were : rods (often hematite) average diameter 40 nm, spherical (nanocube ferrite in origin) sizing around 20nm. Hysteresis Loops have S - shape like to superparamagnetic one. Generally the prepared samples have lower coercivety Hc, higher saturation magnetization Ms compared to these in literatures. Both sets give maximum susceptibility at x=0.5. These results are explained based on composition, cations distribution, cation interactions and particle size. Resonance microwave absorption by using Ferromagnetic Resonance (FMR) test showed that the maximum imaginary susceptibility χ″ is at x=0.5 for set one besides high values of 0.7 and 0.9, with largest linewidth of about 950 G at x=0.7. Set two showed max absorption (χ″) and linewidth at x=0.9. Powders were then mixed with Novalac epoxy by 39.7 %wt. Shortcut - FMR test with no field showed that high absorption to microwave field for frequencies larger than 19 GHz. The explanation of that set two samples have larger absorption than set one is based on hopping conductivity and magnetic parameters (Ms and Hc) variation. Transmission line method by using vector network analyzer in X - band and Ku - band showed that return (reflection) loss RL got minimum at x=0.3 in for set one in X - band whereas that happen at x=0.3 and x=0.5 for set two. Adding Fe2+ lowered the minimum by a factor of more than 1.5. The insertion losses IL in X - band ranging from - 4.5 to - 7 dB. RL and IL in Ku - band have same behavior but their values are lower. RL got minimum at x=0.5 with value of about near to - 18dB whereas it was around - 12dB by adding Fe2+. Average IL in Ku - band - 6dB. Thickness effect is abstracted by enhancing RL and IL but shifting the minimum of peaks to lower frequency. 2mm thick has RL< - 27dB and IL< - 19dB.

الحالات الكمية المتشاكهة المشوهة وبعض تطبيقاتها == q - Deformed Quantum Coherent States and Some of Their Applications

Author name: احمد شاكر محمود ياس
Supervisor name: محمد عبد الزهرة حبيب
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: The concept of q - deformation has found many important applications in a variety of fields in physics, such as quantum optics, atomic physics, solid state physics, nuclear physics and cosmology. This has motivated its extension to many well - established other concepts such as coherent states well - known in quantum optics. On the other hand, the interpretation of the physical meaning of the q - deformation remains an outstanding problem.The present work is an attempt to apply the concept of q - deformed coherent states to solve this interpretation problem. The q - deformed 1 - D quantum harmonic oscillator is used as a model for the application of the methodology of using q - deformed coherent states to solve this problem. This is achieved by first deriving the classical Liouville equation for the q - deformed 1 - D classical harmonic oscillator in the undeformed and deformed oscillator phase spaces. Then, this equation is solved by using the method of characteristics which gives the classical probability distribution function for this oscillator in phase space. The behavior of this function is then investigated by using a computer visualization method based on a computer program constructed in Mathematica® language.On the quantum level, the Heisenberg equation of motion for the density operator corresponding to this 1 - D quantum harmonic oscillator is expressed in the present work in terms of the standard quasiprobability distribution functions, again in the deformed and undeformed phase spaces. This helps to derive the quantum Liouville equations for this q - deformed oscillator in these phase spaces. The classical limits of these resulting Liouville equations are then approached by extending a standard procedure based on the non - deformed coherent states to the q - deformed case. In addition to the application of the standard q - deformed coherent states, a novel approach based on q - deformed coherent states due to Arik and Coon is also employed in this investigation.The results of detailed mathematical derivations in this process of approaching the classical limit reveal that this limit is statistical in nature. This is similar to the case of the ordinary undeformed oscillator which has been proved previously.They also reveal, together with the complementary computer visualizations, more information about the physical meaning of the q - deformation. This includes the observations that the q - deformed 1 - D oscillator can be interpreted as a nonlinear oscillator where the nonlinearity parameter depends on . Also, the behavior of the classical limits of the quantum Liouville equations for this oscillator is observed to show whorl shapes that can be contrasted with their classical analogs.This whorl shape behavior can be considered as a phenomenon connected with q - deformation in general; the anharmonic oscillator being a special case.Some connection with phase space having a non - commutative geometry, resulting from q - deformation, also finds evidence in some of the results presented in this thesis.

تحضير وتوصيف المادة الكهروحرارية ZnxBi2 - xTe3 == Preparation and Characterization of ZnxBi2 - xTe3 Thermoelectric Material

Author name: منال عبد الواحد عبود
Supervisor name: عماد خضير عباس | علي مطشر موسى
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 this project we constructed a DC sputtering system for thepreparation of BiR2RTeR3R (Bismuth Telluride) thin films. BiR2RTeR3R and itsZnRxRBiR2 - xRTeR3R alloys which were prepared in this work by solid solutionas bulk samples and by D.C. sputter as thin film samples. Bothsamples are characterized by X - ray Diffraction Pattern (XRD) and byGrazing Incident Small Angle X - ray Scattering (GISAXS) for thinfilms that have small thickness less than 100 nm. Thin films sampleswere prepared under different deposition conditions (differentdeposition time, different pressure, different voltages and differentelectrodes distance). (XRD) and (GISAXS) results showed that theprepared BiR2RTeR3 Rwas polycrystalline and has high direction at (015)plane in 2????=27.37 ͦ while its alloys at (0015) in 2????=45.12 ͦ and theintensity of the peak increase by increasing Zn amount indicateincrease this plane density. For thin films the (XRD) results show thatthin film prepared under deposition conditions of (0.06 mbar, 900volt, 1 hour, 100 mA and 1cm electrodes spacing distance) areamorphous at thickness less than 200 nanometer and polycrystalline ifthe thickness increases more than 250 nm. A shift in planes presenceis due to the creation of (ZnTe) compound and increase in grain size.Atomic Force Microscopy (AFM) was used to estimate the average grain size of thin film prepared, results showed different average grain sizes depending on the system type and system parameters, also depending on the target composition. DC sputtering system showed lesser average diameter and high roughness that indicates DC sputtering system is suitable for long time deposition high efficiency TE thin film. To investigate the structure of samples Scan Electron Microscopy (SEM) was used and High Resolution Transmission Electron Microscopy (HRTEM) to evaluate the nano inclusion of solid solution.Thickness of some sample was examined by SEM technique where thicknesses of 23 nm, 46 nm and others are estimated. HRTEM Techniques are used to identify the shape of the low dimensions structure produced in the project. It is found that there are particles size with diameter rang about (66 - 107 nm) having uncontrolled shapes and size which were discovered in samples besides nano inclusions of Zn and ZnTe phase.Thermoelectric properties (Seebeck, power factor, conductivity and figure of merit) of all samples (bulk, thin films) were tested .The results show that the maximum Seebeck coefficient for Bi2Te3 as a bulk is (67.02 μV/K) at T=373 ͦ K while adding Zn enhance this value to (123.96 μV/K) at 363 for Zn0.1Bi1.9Te3 and (224.6 μV/K) for Zn0.2Bi1.8Te3 at 348 K and (189.6 μV/K) for Zn0.3Bi1.7Te3 at348 K. on other hand the thin films prepared have larger thermoelectric properties i.e. high seebeck coefficient, high power factor, high electrical conductivity and high figure of merit for all four alloys.

دراسة التحولات الطورية والنقاط الحرجة في منطقة العناصر الارضية النادرة ضمن اطار نموذج البوزونات المتفاعلة IBM - 1 == STUDY OF PHASE TRANSITIONS AND CRITICAL POINTS IN THE REARE EARTH REGION IN THE FRAMEWORK OF INTERACTING BOSOM MODEL (IBM - 1

Author name: فؤاد عطية مجيد العجيلي
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: A systematic study of isotope chains in the rare - earth region is presented. For the chains 144, , , and 150, energy levels, E2 transition rates, and two - neutron separation energies (SNd15460−Sm16014662−Gd16214864−Dy16666−2n) are described by using the most general (up to two - body terms) IBM - 1 Hamiltonian. For each isotope chain a general fit is performed in such a way that all parameters but one are kept fixed to describe the whole chain.In this region, nuclei evolve from spherical to deformed shapes and a method based on catastrophe theory, in combination with a coherent state analysis to generate the IBM - 1 energy surfaces, is used to identify critical phase transition points.The approach used to fix the Hamiltonian parameters leads to a very good global agreement with the recent available experimental data corresponding to excitation energies, B(E2)’s and S2n values. In particular, an excellent agreement with the measured S2n values is obtained, which is considered a key observable to locate phase transitional regions. The analysis presented here is consistent with previous CQF studies in the same region. As a result we find that 148Nd and 150Sm are the best candidates to be critical, but we should remark that 150Nd and 152Sm are not far away from it.
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