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الطلاء المعدني الوقائي لمعدن المغنيسيوم باستخدام السوائل الايونية == Metallic Protective Coatings of Magnesium Metal in Ionic Liquids

اسم المؤلف: رشا حسين علوان
اسم المشرف: هادي محمد علي عبود
الموضوع العام: علوم الكيمياء
السنة: 2017
الموضوع الدقيق: الكيمياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد

دراسة نظرية طيفية لمجموعة من مشتقات 1 , 3 , 4 - اوكسادايازول == Theoretical Spectroscopic Study for a Series of 1,3,4 - Oxadiazole Derivatives

اسم المؤلف: حسن فائز حيدر
اسم المشرف: شذى فاضل السعيدي
الموضوع العام: علوم الكيمياء
السنة: 2017
الموضوع الدقيق: الكيمياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد

القوى الكبرى واعادة تشكيل النظام الدولي : دراسة في فرضيات الصعود والافول == Great Powers And Reforming International System A Study In The Assumptions Of Ascendancy And Decline

اسم المؤلف: علي بشار بكر اغوان
اسم المشرف: محمد ياس خضير
الموضوع العام: العلوم السياسية
السنة: 2017
الدرجة: دكتوراه
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Constitute the rotation exponential relationship dimensions positive and negative between the international system over the different stages of the major powers in various manifestations, argumentative and extensive research and one of the main gates of understanding of international relations at the contemporary stage, this relationship has opened ample room for endoscopy and research in but the international system and major powers dramatically, impact, vulnerability and nutrition, nutrition reverse dual between the international system and major powers relationship has alternated according to each stage and this relationship is the main problem of the balance of power in several stages, and when he was urgently needed because of the international system is to be the foundation standard for classification of power arrogance in the world, we became our international system stable and clearly defined in terms of the formation of systemic in different structural dimensions, that the international system is established the concept of structural and quality of states and impose the rhythm of movement for many reasons, notably that the nature of the regime often imposes itself a great obligation for these forces because adopted for fear of imbalance or break up of certain international situation or threat to the status of this or that country. While it is possible that just the opposite is happening as they become the major powers in the zenith of its power is granted international system and give it structure and posed or change the balance, that is, the major powers here are the ruler and the clutch on the decision to change within the system and not vice versa.Of course, and as far as what the major powers and the international system and the issues of restructuring strategy and the required strategic supplies, it became clear manner that does not accept the argument that the concept of power and public and private as has changed helped broadly to re - read the beliefs of the strategic countries in terms of the ups and build self - mechanisms .Importance of the study : Centric importance of the study of it represents an attempt research earnest to form a new theory to explain how they can through the major powers arise strategic detail the destruction, they also offer hypotheses second supplement to the theory of looking at the mechanics of the fading of states and their tracks and provide detailed explanations of the forms of collapse and form, in the sense that the subject of major powers and reshape the international system based on the assumptions of ascent and decline, it represents an attempt to re - read international relations in general and major powers and the international system, in particular in the pot research focuses on the scientific methodology of the measurement, audit and observation and select the tracks.The problem of the study : The study generally runs from the two problems main ways : the first, which is problematic conceptual theory relating to the characterization of and what the big powers and the international system and the nature of the dialectical relationship rotating between the two, the second is problematic current major powers characterization and put it in its proper place according to the hypothesis of ascent and decline and the compatibility of all the power with these hypotheses.The dilemma conceptual first, since the study is trying through, and over the detective and three chapters, the first - the first, second and third - explain what the clash incident between the international system and major powers, as it is trying to study here and across this part of the dilemma that the disintegration of the complex Association about the presence of overlapping relationship is a clear path between the evolution of the international system on the one hand and major powers on the other hand, due to the complexity of the actors and their diversity and change the concept of power and its vocabulary, this relationship appears frequently as a rotational (ie, when they vibrate and weaken the international system, is restored and fed through strategic reaction of major powers on the form of finding a new strategic balance or maintain the strategic balance as and when it weakens the major powers, the system modifying itself in line with the size of the weakness incident to correspond to the requirements and elements of modernization that has occurred in the international environment and gives the stream additional to those strengths that have benefited from the decline in single actors function or polar strategic act also shall be either by maintaining a balance or modify it identifies with the size and manage change).While Applied dilemma second focuses on practical models of major powers and try to determine its position in the international system based on key assumptions that have been developed and adopted a basic criteria for the rise of the big powers and the eclipse, as it dealt with the last three chapters (IV, V and VI) the issue of the status of all power in the international system - models selected - based on the extent of approaching and distancing itself from the hypotheses that have been put forward both in terms of climb or, moreover study focuses in this part of the dilemma defines the shape of the future of the international order based on the data and the reality of the big powers. It is through this dilemma offers a number of central research questions that the study will try to answer them through the next research context, the most important of these questions are : 1. What is the fundamental nature of the relationship between the international system and major powers?2. How can identify the key ingredients that require their presence in the power of any wish to become a major international scope of the system?3. What are the main forms of balance known to international relations throughout history, the nation - state?4. Who are the actors function capable of control in the international system and restructuring?5. How can identify the entrances of change within the international system and who knows this change?6. What is the most important hypotheses that can be through to become a major force on the international scope of the system?7. How can identify the most important hypotheses decline that lead them to collapse?8. Do not slip United States a world power?9. Is Russia today is on its way toward building the same to you mean by itself as one of the poles of the future world again?10. Is China really able to replace the United States? And how?11. What is Japan's new site in the international system?12. What is the future of the international system in the light of data the rise and fall of great powers?Hypothesis of the study : Consistent with the dilemma that have been submitted and research questions that have been submitted and as well as the main hypotheses that have been adopted by the study systematically through the third quarter in an attempt to form a comprehensive theory, the study starts from the assumption president of that on the basis of (that there is a direct correlation "positive + negative" between the regime the one hand and major powers on the other hand. The more major powers more coherent and stronger the more you process the formation of the international system more discipline, and vice versa, the more the international system more solid whenever the major powers to maintain more balance and less likely to change. And branching out from this hypothesis President, two assumptions in two basic subgroups : The first hypothesis : Whenever any major international force backed away from its position, as it was an opportunity to push a new force to fill the vacuum, and this is a dialectical ascent and decline.The second hypothesis : Whenever a major international force backed away from its position as it was an opportunity to reshape the international system according to the new balance of power. This is the dialectical relationship between the international system and major powers.Curricula : The study used the six - round main chapters range of approaches that are used in scientific research on the scope of political science were as follows : 1. The historical approach, which sought the study through used to display the most prominent of the relevant idea of historical experiences and the subject that the researcher wants to clarify, this has been the approach one of the main approaches that have been through it to identify the mechanisms of the fading of the major powers and the conclusion of which many hypotheses have been one of the most important pillars of the study at various stages.2. Analytical Approach : The study used the analytical approach to the study of various plants for several purposes, the most important cases of the dismantling and re - installed in accordance with the main theme of her service, and the support of the conclusions of this approach is based on the basis of scrutiny of reality and studied extensively studied through strategic insight.3. Approach the international system Analysis : It is one of the most major and modern approaches that study sought to focus on it through international structural analysis and situations experienced by the international system and the dismantling of his limbs and its impact, the study was able bumpy this approach to reach many conclusions based on what provided by this approach of the mechanics to understand the phenomenon and absorbed significantly.4. Approach to measure the strength of nations : one of the most important approaches and, most recently that for its research tools have enabled the study to identify the most prominent features of the strength and the weakness of the major powers and greatly helped to explain many of the phenomena and dismantled as it should.5. Future Approach : It is one of the most important methods you used for the purposes of study, the most important of several identifying features scenes of the future of the international system according to the scene forward - looking unconditional. Structural study : As well as the introduction to the study and details and the conclusion and findings, the study contained two doors presidents by six central chapters, the first section by three chapters titled (conceptual framework and theoretical), while Part II came with three other chapters supplement entitled (Applied and future frame).Ensure that the first chapter of the study, which came under the title (the major powers and the international system), the two main two sections (Section I : what the major powers and the international system) while the second part, titled (forms of power in the international system balance).On the other hand Chapter II of the study, which was titled contained (actors in international relations and the entrances to change) on two sections two main (Section I : actors function traditional and new actors function of non - State actors in international relations), while the second section under the title (the entrances to the change in the system international).Also a third chapter of the study, which was titled (hypotheses rise and fall of great powers) of the two main two sections (Section I : hypotheses rise of major powers) while the second part, titled (hypotheses fading major powers).Chapter IV of the study contains two sections and two presidents, who came under the title (the major powers "core" and measuring hypotheses ascent and decline), was the first topic title (the United States) while the second section title (Russian Federation).On the other hand, Chapter V of the study complements the above by two sections presidents under the title of president of the chapter came a (major powers "emerging" and measuring hypotheses ascent and decline), was the first section of the chapter entitled (China), while the second part, titled (Japan) .

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

اسم المؤلف: عمار عبد الستار زغير الراوي
اسم المشرف: سعد ناجي عبود | ليث عبد العزيز العاني
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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.

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

اسم المؤلف: غفران عبد علي
اسم المشرف: سعد ناجي عبود
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: اسراء ماهر جمال
اسم المشرف: عماد خضير الشكرجي
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: نداء طه ياسين
اسم المشرف: علاء جبار غزاي
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: نذير بشير محمود
اسم المشرف: عماد خضير الشكرجي
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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 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

اسم المؤلف: محمد محسن نعمة
اسم المشرف: ندى فاضل توفيق
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء الذرية
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: لبابة عبد الكریم الجنابي
اسم المشرف: سھى موسى خورشید الاوسي
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء الذرية
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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.

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

اسم المؤلف: علي حسين صالح
اسم المشرف: قاصد عبد الستار صالح الجنابي
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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.
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