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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.

معالجة رقمية وتحليلية للاثار الناتجة من التشعيع بالمصدر النيوتروني 241Am - 9Be على بعض كواشف الاثار النووي للحالة الصلبة == Digital Processing and Analysis for the Tracks Produced From the Irradiation with Neutrons Source 241Am - 9Be on Some of Solid State Nuclear Track Detectors

Author name: مصطفى يوسف رجب
Supervisor name: حسين علي الجبوري
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: Image processing technique was used in a lot of studies and research and it concluded , including a number of mathematical relations . In this study , two programs were used , the first one; MATLAB program and second Image - J program . These programs were used to tracks analysis of α - particles on the nuclear track detectors type CR - 39 and CN - 85 . Where irradiated detectors by thermal neutrons from (241Am - 9Be) source with activity 12Ci and neutron flux 105 n.cm - 2.s - 1 . Which obtained on incident α - particles for detectors through 10B(n, α)7Li interaction after covered it with boric acid H3Bo3 pellets . The irradiation times - TD for both detectors were 4h , 8h , 16h and 24h .Through the analyze irradiated detectors of using MATLAB outputs for found the following relationships : a)The irradiation time - TD has behavior linear relationships with following nuclear track parameters, Total track number - NT, Maximum track number - MRD (with depended on track diameter - DT at range of radiation response region 2.5μm - 4μm and 2.5μm - 5μm for CR - 39 and CN - 85 detector respectively) and Maximum track number - MD (without depending on track diameter - DT). b) The irradiation time - TD has behavior exponential relationship with maximum track number - MRA (with depended on track area - AT ) at range of radiation response region 7μm2 - 24μm2 and 9μm2 - 35μm2 for both CR - 39 and CN - 85 detector respectively. c) The irradiation time - TD has behavior a logarithmic relationship with maximum track number - MA (without depending on track area - AT).While through the analyze of outputs Image - J program for irradiated detectors found the irradiation time - TD has behavior linear relationships with following nuclear track detector parameters : a) Total track number - NT. b) Maximum track number - MRA (with depended on track area - AT ) at range of radiation response region 12 μm2 - 24μm2 and 5 μm2 - 27μm2 for both CR - 39 and CN - 85 detector respectively. c) Maximum track number - MA (without depending on track area - AT)This study show that MATLAB program was more analytical and accuracy from Image - J program , through the logarithmic behavior for both detectors between irradiation time - TD with the maximum track number - MA (without depending on track area - AT). There is the possibility of future use image analysis of MATLAB program in the other nuclear track parameters analysis , including ; etched velocity - Vt, , track diameter - Dt , critical angle of nuclear track - θt , nuclear track depth - Dp .The image analyze technique for nuclear track detector which obtained from this study especially with regard to track diameter - TD can be take into account for classification of α - particle emitters , In addition to introduce this technique in preparation of nano - filters and nono - membrane in nanotechnology fields

تحضير ودراسة المركبات SnxBa4Ca2Cux+4Oy وYnBa5Cun+5Oy == Preparation and Characterization of the SnxBa4Ca2Cux+4Oy and YnBa5Cun+5Oy Compounds

Author name: رؤى فخري هادي
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 present study includes the preparation of SnxBa4Ca2Cux+4Oy and YnBa5Cun+5Oy compounds with (x = 3, 4, 5, 6, 7) and (n=3, 5, 7) by solid state reaction (SSR) method. The study was to conclude the superconductor behavior of both compounds. The prepared samples were analyzed by Meissner effect primary, and the excess oxygen content was measured by using Iodomertric titration method. The samples characterized by XRD patterns with computer program that was used to determine the value of lattice constant, Scanning Electron Microscope (SEM), Energy dispersive X - ray spectroscopy (EDS) to study the grain morphology and also resistivity measurement was performed by Van der Pauw method to conclude the nature of behavior.The resistivity measurement results of Sn - Ba - Ca - Cu - O system showed that the semiconducting behavior, increases with decreasing the temperature toward low temperature, the lowest and the highest normal resistivity were found at x=6 and at x=4, respectively. The system Y - Ba - Cu - O showed a superconductor behavior with high transition temperature, the Tc at n=3 of about (113.6 K), the sample prepared with n=5 has Tc=113 K, meanwhile the sample prepared with n=7 has Tc=105 K.The x - ray analyses for SnxBa4Ca2Cux+4Oy samples showed that the tetragonal structure, and the c - parameter increased by increasing the value of (x) until reach to maximum value at x=5 then return back decreasing at x=6 and 7. The x - ray diffraction analysis of the compound YnBa5Cun+5Oy has orthorhombic phase and when Y - atom concentration and the number of CuO2 layer increased tend to increase b and c - axis.The Scanning Electron Microscopy (SEM) results showed that the appearance of nanostructure in Sn6Ba4Ca2Cu10O22 and Sn7Ba4Ca2Cu11O24 samples in the range (100 - 300 nm), whereas the other samples of Sn - familywas a microstructure. On the other hand, the Y - 358 had large grains randomly comparable with Y - 5 5 10, Y - 7 5 12 addition to absent the interfaces distances from Y - 358. The results of EDS showed that the agreement of the peaks appeared with the theoretical values.

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.

تصنيع وتوصيف مفتاح بلازما الومضة الكاذبة ذو القدرة العالية == Construction and Characterization of Pseudospark High Power Plasma Switch

Author name: بسمة حسين حمد الشمري
Supervisor name: احمد كمال احمد | كمال حسين لطيف
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

محاكاة عامل تراكم الجرعة لاشعة كاما متضمنا تاثير اشعة الفناء للالمنيوم، والحديد والرصاص == Simulation of Dose Buildup Factor of Gamma Ray Including Annihilation Radiation for Aluminum, Iron and Lead

Author name: مروة صباح مهدي
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: A computer program based on Monte Carlo method had been designed and written in visual basic computer language and utilized for simulating the classic problem of gamma ray beam incident on finite plane slabs of absorbing materials. The source geometry adopted in this program is plane normal source.Dose buildup factor of gamma photons in the absence and presence pair production effect have been calculated in the energy range (4 - 10) MeV for aluminum, iron, and lead up to 5 mean free path thickness.Some of physical parameters has been studied and the simulation results indicates the following remarks : • Gamma ray buildup factor increases with the increase of the thickness for the three shielding materials, this increase in dose buildup factor is due to the increase of scattering with the small angles and with the increase of the thickness of the material.• Dose buildup factor for low atomic number material (Al, Z=13) is higher than that for medium (Fe, Z=26) and heavy (Pb, Z=82) material for the same photon energy (10MeV). A rapid decrease of the buildup factor values with the increase of Z is seen. This dependence is in a good agreement with the fact that the proportion of the cross section for Compton effect decreases with increasing atomic number, therefore the Compton effect plays a more significant role in lighter materials which have lower atomic number (Z).• Dose buildup factor is inversely proportional with the increase of energy within the studied enrgy range (4 - 10)MeV. This behavior can be explained that the cross section for Compton scattering within the studied energy range is decreased with increase ofenergy and this means that the probability of scattering is decreased and it is finally reflected on the buildup calculation, since the scattering plays an important role in determination of buildup factor.The rate of increase in the value of dose buildup factor in lead (Z = 82) higher than iron (Z = 26), and the last is more than that for aluminium (Z = 13). This is due to the effect of pair production interaction which is directly proportional with the square of atomic number.Dose buildup factor in the presence of pair production is higher than dose buildup factor in the absence of pair production effect. The deviation between the values of dose buildup factor in the presence and absence pair production is increased when the energy is increased within the studied energy; this mainly due to the increase of cross section for pair production values within the studied energy range.

دراسة الخصائص النووية التركبية والانتقالات الكهرومغناطيسية لانوية Kr ، Xe ، Nd ، Ge الزوجية - الزوجية باستخدام نموذج البوزونات المتفاعلة == Study of Nuclear Structure Properties and Electromagnetic Transitions for even - even Kr , Xe , Nd , Ge Nuclei in the Framework of Interacting Boson Model

Author name: عبد القادر سعد عبد القادر
Supervisor name: سعد ناجي عبود
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: لقد تم في هذا البحث دراسة التركيب النووي والانتقالات الكهرومغناطيسية لبعض النظائر (الزوجية - الزوجية ) Nd , Xe , Kr وGe باستخدام النموذج الجماعي ( نموذج البوزونات المتفاعلة الثاني IBM - 2 ) . تم الحصول على نتائج لمستويات الطاقة، والانتقالات الكهربائية B(E2) , الانتقالات المغناطيسية B(M1) , ونسبة الخلط (E2/M1) ، وعزم رباعي القطب الكهربائي ، وعزم ثنائي القطب المغناطيسي ، والانتقالات احادية القطب . ولقد تم مقارنة النتائج مع القيم العملية المتوفرة وقد وجد انها متقاربة ومقبولة . ان نظائر ال Kr (Z=36 ) تقع في المنطقة الانتقالية القريبة من التحديد الاهتزازي. ولقد تم حساب مستويات الطاقة B(E2) ، B(M1) ، (E2/M1) وX(E0/E2) لبعض الانتقالات المختارة باستخدام نموذج البوزونات المتفاعلة الثاني (IBM - 2) وان جميع النتائج قد قورنت مع القيم العملية. لقد كان لمعاملات ماجيرونا اثرا كبيرا في حساب مستويات الطاقة , , , التي حددت انها تمتلك صفات تناظر مختلطة . لقد تم مقارنة نتائج نظائر Xe التي تم الحصول عليها من نموذج IBM - 2 مع التوقعات النظرية لتماثل النقطة الحرجةE(5) . وتبين ان 128Xe هو ليس نظير يقع ضمن E(5) كما اقترح مسبقا . لذا فان نسبة الطاقة لنظير ال Xe128 ( ) تقع بين E(5) وحدود - softγ . وبذلك فحسب هذه النسبة فان 128Xe يجب ان يقع بين E(5) وO(6). غالبا ما يكون اختبار 130Xe مناسب لنظائر Xe ، والذي يظهر خصائص E(5) بافضل حالته. كذلك فان مستويات الطاقة تعزز وجود هذا النظير ضمن E(5) . اما بالنسبة لنظائر 132Xe و134Xe فانها تظهر صفات مشابهة للمحدد الاهتزازي SU(5) . ان مستويات التناظر المختلطة قد تم التعريف عليها من نظائر Xe وهذا قد مكننا من تعقب تحرير فونون واحد لحالة في سلسلة النظائر ( الزوجية - الزوجية ) للزنون من الاهتزازات القريبة من N=82 الى نواة - softγ باتجاه منتصف القشرة . لقد درسنا الخصائص النووية لنظائرNd (A=144 - 154) في IBM - 2 وتم الحصول على نتائج جيدة مقارنة بالقيم العملية . 144 - 150Nd يقع في المنطقة الانتقالية ( الاهتزازي - الدوراني ) SU(5)→SU(3) .بينما نظائر 152 - 154Nd فانها تقع ضمن التحديد الدوراني (SU(3)) . ان X(5) سوف ياخذ مكان او حيز عندما يستمر بحركته بين تناظر U(5) الى تناظر ال SU(3) ويظهر ذلك بصورة واضحة ما بين مستويات الطاقة وقوى الانتقال رباعي القطب E2 . لقد وجد حديثا ان سلسلة نظائر Nd تشير الى الانتقالات الطورية كما ان نظير Nd150 يعرضا الخواص المتوقعة ل X(5) . على العموم فان هناك عدة دراسات مفصلة بحاجة للحصول على تلك المؤشرات . وبالنهاية نستنتج بان بعض نظائر Nd تكتشف خواص X(5) . ان , هي حالات تناظر مختلطة لنظائر Nd ان نموذج البوزونات المتفاعلة IBM - 2 كان ناجحا بوصفه للخواص التجميعية للنواة . وفي هذا البحث قد تم الاهتمام بالتطبيقات النظامية والمتضمنة اشكال البوزونات المختلطة.ان النظائر الجرمانيوم ( الزوجية - الزوجية ) لها اهتمام خاص بسبب وجودها ضمن مجموعتين من الحزم ذات الخواص المعقدة للنواة الخفيفة . ان نموذج البوزونات المتفاعلة IBM - 2 مع التركيبات المختلطة يجهز توصيف جيد لكلا الحالات المبينة بالمستوى الارضي وللبروتونات الموجودة بالمستوى المتهيج عبر غلاف القشرة Z =28 المغلق . لقد تم دراسة نظائر الجرمانيوم وتبين انه يتدرج مابين وسط قشرة البروتون والقشرة المزدوجة القريبة من المغلقة عند ال 82Ge . ولقد وجد ان نظائر الجرمانيوم عند التشكيل Nπ=2 تاخذ الشكل الاهتزازي وعند التشكيل Nπ= 4 تاخذ الشكل الدوراني ( ويزداد التشوه) . وفي هذا العمل استخدمت طرق حديثة جدا لتعيين الشحنات الفعلية (effective charge) للبوزونات وذلك باستخدام القيم العملية للانتقال رباعي القطب (0_1^+ 2_1^+ B(E2; وكذلك استخدمت طرق جديدة لحساب المعاملات الجيرو مغناطيسية للبوزونات gυ ، gπ وذلك بمعايرتها الى القيم العملية لـ B(M1) وδ (E2/M1) . | Nuclear structure Properties and electromagnetic transitions of some even - even Kr, Xe, Nd and Ge isotopes have been studied in this work, by using the collective Interacting Boson Model - 2 (IBM - 2). The Interacting Boson Model (IBM - 2) has been very successful in describing the collective properties of nuclei. This work concerns a systematic applications of the model, involving configuration mixing of bosons.There have been extensive IBM studies of low - lying positive parity bands, which are based on the ground state and the quadrupole degree of freedom. The results for energy levels, B(E2), B(M1), mixing ratios , quadrupole and magnetic dipole moments and monopole transitions, were compared with some previous experimental and theoretical values. It was found that an acceptable degree of agreement between the predictions of the IBM - 2 and the experiment can be achieved. The Kr isotope (Z = 36) lies in the transitional region closer to the vibrational range of nuclei. Energy , levels B(E2), B(M1) and the mixing ratios δ(E2/M1) and X(E0/E2) for selected transitions in this isotope were calculated in the framework of the interacting boson model (IBM - 2). All results were compared with experimental data. Some experimental X(E0/E2) ratios were calculated from available experimental data. Majorana parameters were found to have a great effect on the calculated energy levels of the , , and states which indicates they have mixed symmetry properties. The results of IBM - 2 for Xe isotopes were compared with the theoretical predictions assuming a critical point symmetry E(5) which leads to conclude that 128Xe is not an E(5) isotope as previously suggested. In this case of the 128Xe the observable is intermediate between the value for E(5) and gamma soft limit . The ratio suggests that 128Xe should lie between E(5) and O(6). Similar test using 130Xe as a most likely candidate amongst the Xe isotopes, conclusively demonstrate a how well E(5) is realized in the best case. The energy ratio confirmed that this isotope an E(5) critical point symmetry. The 132Xe and 134Xe show vibrational - like character (SU(5) limit). 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 states or at least a fragment of it have been identified in Xe isotopes. This enables us to trace the evolution of the one - phonon states in the even - even xenon isotopic chain from the vibrators near N = 82 to the γ - soft nuclei towards mid - shell. We have studied the nuclear properties of Neodymium isotopes with (A =144 - 154) in IBM - 2. A good agreement results with the experimental data. 144 - 150Nd lie in the transitional region (virational - rotational limit SU(5)→SU(3)). For the 152 - 154Nd isotopes the energy ratio are well described by the rotational limit SU(3). The X(5) symmetry would take place when moving continuously from the pure U(5) symmetry to the SU(3) symmetry and it implies a definite relations among the level energies and among the E2 transition strengths. It was recently shown that a signature of phase transition is observed in the chain of Nd isotopes, 150Nd display the predicted features of the X(5) symmetry and mark therefore the critical point. However, more detailed studies and experiments are needed to get ideas about this signature. At the end, we have concluded that some of Nd isotopes display X(5) symmetry features. The and are mixed symmetry states in Nd isotopes. The even - even isotopes of germanium are of special interest because of the coexistence of two sets of bands, of very different character, in the lighter nuclei. The IBM - 2 with configuration mixing provides a good description, both of states built on the normal ground state and of those associated with a proton pair excitation across the Z =28 closed - shell gap. Ge isotopes are studied, ranging from the middle of the neutron shell to very near the doubly closed shell at 82Ge. Same Hamiltonian is used for all the nuclei studied, with parameters which are constant or smoothly varying

تخمين معاملات زيوغ العدسه المغناطيسية باستخدام الحل التحليلي لمعاده المسار القريب من المحور == Magnetic Lens Aberration Coefficients Estimation by Using the Analytical Solution for the Paraxial Ray Equation

Author name: رشا يوسف حمد
Supervisor name: عدي علي حسين | 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: اجريت دراسة نظريه باستخدام الصيغه التحليلية لمعادله المسار شبه المحوري للالكترون وذلك لتحديد افضل الخواص البصريه للعدسة المغناطيسية. تم دراسهة معاملات الزيوغ كمعاملات الزيوغ الكروية, اللونيه, التشويه القطري واللولبي. اعتمد في هذا البحث انموذج الشكل الناقوسي لكلاسر لتمثيل توزيع المجال المحوري للعدسة المغناطيسية. وقد اخذ بنظر الاعتبار حالتين للزخم الابتدائي في الحسابات بوجوده او عدم وجوده في الحالتين. ان الوصول الى امثل النتائج قد انجز من خلال تغير بعض المعاملات المؤثرة مثل نصف العرض عند نصف الحد الاقصى(a= 2.01, 2.02, 2.03 and 2.04 mm), والحد الاعلى لكثافة الفيض المغناطيسي (Bm= 0.001, 0.002, 0.003 and 0.004 Tesla) وزاوية انبعاث الالكترون (0.2, 0.4, 0.5 and 0.6 rad= θ).من خلال النتائج تبين ان افضل قيم a تساوي 2.04 mm في حاله وجود او عدم وجود الزخم الابتدائي في الحسابات. وقد وجد ايضا ان كل من قيم الزيغ الكروي, اللوني والتشويه اللولبي يقل بزيادة a, بينما اقل قيم للزيغ الكروي والتشويه القطري في الحاله الاولى عندBm يساوي 0.004 Tesla.ووجد ايضا ان افضل الزوايا للالكترون (θ = 0.2 rad) وهي تتناسب طرديا مع معاملات الزيغ اللوني والتشويه اللولبي.ومن جهة اخرى تبين ان الزيغ الكروي والتشويه القطري له قيم سالبه وهذه المعاملات ممكن استخدامها كمصحح في المنظومات البصرية. | A theoretical investigation is carried out by using an analytical expression for paraxial trajectory of an electron in a magnetic lens to estimate the optimum properties of the magnetic lens. The aberration coefficients of the magnetic lens are studied, such as the spherical, chromatic, radial distortion and spiral distortion aberration coefficients. The Glaser's bell - shaped model is adopted to represent the axial field distribution of magnetic lens. The initial momentum of the electrons is taken into account, where the calculations are made for two cases : when the electrons have zero and non - zero initial momentum values . The optimization role is achieved by changes some of the effective parameters at the range of the half - width at half maximum (a = 2.01, 2.02, 2.03 and 2.04 mm), the maximum magnetic flux density (Bm = 0.001, 0.002, 0.003 and 0.004 Tesla) and the electron emission angle (θ = 0.2, 0.4, 0.5 and 0.6 rad). In the present results the optimum values for both cases of the initial momentum is found at the half - width at half maximum equal to 2.04 mm, and the values of the spherical, chromatic and spiral distortion aberration coefficients decreased as the half - width at half maximum (a) increased, while the minimum values of the spherical and radial distortion aberration coefficients are found at Bm = 0.004 Tesla in the first case. However the best angle is found at θ = 0.2 rad which is directly proportional which chromatic and spiral distortion aberration coefficients. On the other hand the calculations appeared that the negative values for both spherical and radial distortion aberration coefficients are estimated and these coefficients can be used as corrector in the optical systems.

محاكاة حاسوبية لجهاز صوتي بصري لنظام فوتوني == COMPUTER SIMULATION OF AN ACOUSTO - OPTICAL DEVICE FOR PHOTONIC SYSTEM

Author name: مروة كمال مصطفى
Supervisor name: اياد عبد العزيز العاني | 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: Acousto - optics science deals with the interaction between sound and light waves. Acousto - optic waves are most important in transferring signals through the communication systems, since modulating signals takes a great advantages in the field of communication engineering, bio - medical, laser beam deflection and laser intensity modulation.The aim of this work is to simulate the fundamentals of an Acousto - Optic Modulator. The simulation procedure is based on theoretical and computational relationships describing acousto - optic properties for three selected materials which are “Glass, Germanium, and Tellurium - Oxide”. Two computer programs have been written using “MATLAB” software, the first used to verify the normalized intensity of the diffracted orders versus peak phase delay using partial differential equation, while the second program is used to study the normalized intensity of the electric field versus time wave propagation and electro - magnetic wave propagation in x, y and z directions, using Finite Difference Time Domain. The results for Glass and Tellurium - Oxide materials shows that the periodic exchange of the normalized intensity between the zero and first orders becomes smaller as the interaction length D increase, this indicate that the higher orders may appear very clear in these materials. The results for the Glass material show that the normalized intensity of the electric field increases with increasing electromagnetic wave propagation in x, y and z directions.

ضغط الصوت باستخدام الكسوريات == Fractal Audio Compression

Author name: وسام فوزي جاسم محمد
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: لقد استحدثت طرق ضغط عديدة باستخدام تقنيات مختلفة الغرض منها تحقيق نسب ضغط عالية مع المحافظة على جودة الصوت المضغوط, مع الاخذ بنظر الاعتبار انجاز الضغط باقل وقت ممكن.طريقة الضغط الكسوري هي احدى هذه الطرق التي يرافقها ضياع بالبيانات وتعتبر من طرق الضغط الحديثة وتعتمد على عملية ايجاد مجاميع محددة وصغيرة من المعادلات الرياضية التي تصف الاشارة . بارسال معاملات هذه المعادلات الى محلل الشفرة يمكن اعادة تشكيل الاشارة الاصلية.بايجاز ضغط الصوت الكسوري يعتمد على مبدا نظام التكرار المجزئPIFS) ). ضغط الصوت الكسوري يستغل ال(Affine redundancy) والتي تتواجد في الصوت, هذه ال (redundancy) ترتبط بالتشابه الذاتي للصوت.بكلمة اخرى ضغط الصوت الكسوري يقوم بايجادالا نماط المتشابهة والتي تتواجد بقياسات مختلفة(different scales) واماكن مختلفة(different places) في الصوت, وبعد ذللك يقوم بحذف اكثر ما يمكن من ال(redundancy).هذا البحث يهدف الى محاولة التحقق من امكانية تطبيق الضغط الكسوري في عملية ضغط الصوت. النظام المعتمد يتكون من مرحلتين : المرحلة الاولى مرحلة التشفير(Encoding Unit) والثانية مرحلة فك التشفير ) .(Decoding Unitفي مرحلة التشفير يجزا الصوت الاصلي الى نوعين من الكتل, كتل تدعى كتل المجال المقابل ((Range Pool وهي كتل غير متداخلة, وكتل تدعى كتل المجال (Domain Pool) والتي من الممكن ان تكون متداخلة. ومن ثم يتم تقطيع الصوت باستخدام طريقة التقطيع المتساوي للكتل الى كتل متساوية الحجم. بعد ذلك يتم ايجاد افضل كتل في المجال لكل كتلة في المجال المقابل وذلك بتطبيق احد انواع التحويلات وتدعى((Affine Transformation .تنتهي مرحلة التشفير بخزن تفاصيل (معاملات )هذه التحويلات لكل كتلة من كتل المجال المقابل .ان عملية ايجاد الكتل المتشابهة تتطلب عمليات حسابية معقدة تستغرق وقت طويل وهذا ما يؤخذ على طريقة الضغط الكسوري كنقطة ضعف.ان البرامجيات التي تم بناؤها لهذا الغرض تم اختبارها باستخدام خمسة نماذج لبيانات صوتية. لقد تم تنفيذ النظام المعتمد باستخدام فيجوال بيسك6.0 كلغة برمجة, تم استخدام معدل الخطا التربيعي((MSE ونسبة الاشارة الى التشويش((PSNR كمعاملات حساب دقة النتائج المستخلصة من التقنية الكلية في النظام المعتمد.و كانت بعض النتائج المستخلصة من البحث هي بالنسبة للعينة الاولى في حالة حجم الكتلة تساوي (60 ) فان نسبة الضغط (15.51 : 1), اما العينة الثانية في حالة حجم الكتلة تساوي (40) فان نسبة الضغط (11.51 : 1), وفي حالة حجم كتلة صغيرة كما في العينة الثالثة والتي تساوي (20) فان قيمة ال(PSNR) جيدة وتساوي (35.76 dB), وكذالك للعينة الاولى في حالة حجم الكتلة تساوي (10) فان قيمة ال(PSNR) تساوي (45.63 dB). | Fractal audio compression is based on the concept of a partitioned iterated function system (PIFS). Fractal audio compression exploits the affine redundancy that is commonly present in audio; this redundancy is related to the similarity of an audio with itself. In other words, fractal audio compression finds similar patterns that exist in different scales and different places in audio, and then eliminates as much redundancy as possible. In this work the possibility of implementing fractal audio compression is investigated. The implemented system consists of two major units; the first is the Encoding unit and the second is the Decoding unit. Encoding is done by partitioning the range pool (which is the original audio) into non - overlapping blocks, called range blocks, and partitioning the domain pool (which is the result of the original audio after down sampling) into overlapped blocks with the same size of range blocks called domain blocks. A fixed size - partitioning scheme is used to partition the domain pool and the range pool. After generating the range and domain pools, for every range block, the best - matching domain block in the domain pool is searched for by performing a set of affine transformations on them. Thus the encoding is completed by saving the optimal affine parameters for every range block. The Decoding process can be done by repeatedly applying the affine transformation on an initially blank audio and its subsequent reconstructed audio, until it completely reconstruct an approximate wave to the original audio. The time required to compress an audio file is affected by the size of each block being extracted from the proceed audio file; this means smaller block size implies longer time required to compress the corresponding audio file.The implemented system was tested using five wave samples of data. The proposed work was implemented by using Visual Basic (6.0) as a programming language, the fidelity measure MSE and PSNR were used to check the results of the whole implemented technique. The best results obtained from the implemented system were for the test (sample - 1) in case were block size equal to (60) the compression ratio is (15.51 : 1), also for test (sample - 2) were block size equal to (40) the compression ratio is (11.03 : 1), and for small block size as in test (sample - 3) were the block size is (20) the value of the PSNR is good that its equal to (35.76 dB), also for test sample - 1 when the block size is (10) the PSNR value (45.63 dB).

معالجة رياضية لدراسة تغير التركيب المسامي مع ظروف التشكيل للمواد المسامية == Mathematical Manipulation to Study the Changes of Porous Structure with the Formation Conditions of Porous Materials

Author name: سديم عباس فاضل القصاب
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 تطوير نموذج مجسم يصف عملية االتكثيف خلال عملية الحرق الزجاجي (التزجيج) لمادة تحتوي على محتويات صلبة. هذا النموذج تم تطويرة من نموذج سابق للباحث Scherer والذي وضع نموذج يصف عملية التكثيف خلال عملية الحرق لمادة لا تحتوي على محتويات صلبة.النموذج المطور استخدم لمحاكاة معدل التكثيف خلال عملية الحرق لمواد سيراميكية غير متجانسة تتكون من خليط من بعض الاطيان العراقية والتي تم تحضيرها من بحث سابق. النموذج المطور تم استخدامة لدراسة تاثير عدة عوامل على عملية التكثيف خلال عملية الحرق وهي درجة حرارة الحرق، زمن الحرق والنسبة بين حجم المواد الصلبة الى حجم السائل الزجاجي، كما استخدم النموذج المطور في تقدير قيم اللزوجة الفعالة للسائل الزجاجي المتكون خلال عملية الحرق. كذلك تم تطبيق نموذجان اخران للمواد غير المتجانسة هما نموذج الكرة المركبة ونموذج المكون الذاتي وجرى استخدامهما لدراسة تاثير درجة حرارة الحرق وزمن الحرق على عملية االتكثيف لغرض مقارنة النتائج من هذين النموذجين مع نتائج النموذج المطور. كذلك تم استخدام النموذج المطور لدراسة تاثيرتوزيع حجوم المسامات على عملية التكثيف وذلك بفرض توزيع كاوس لحجوم المسامات واعادة صياغة المعادلات للموديل المطور لجعلها تعتمد على الانحراف المعياري لتوزيع حجوم المسامات. العوامل الفيزيائية مثل اللزوجة تم حسابها من خلال عملية المطابقة (fitting ( للنتائج العملية لعملية الحرق للنماذج. تم تصميم برامج حاسوبية بلغة ( (FORTRAN 90لدراسة تاثير درجة حرارة الحرق على عملية االتكثيف باستخدام النموذج المطور، نموذج الكرة المركبة ونموذج المكون الذاتي. هذة البرامج تم تحويرها فيما بعد لمحاكاة عملية االتكثيف كدالة لزمن الحرق. كذلك برنامج اخر تم تصميمة لدراسة تاثيرتوزيع حجوم المسامات على عملية التكثيف خلال عملية الحرق باستخدام النموذج المطور. النتائج من برنامج الموديل المطور تحقق افضل مقاربة للنتائج العملية تليها النتائج من برنامج موديل الكرة المركبة. النتائج من برنامج تاثيردرجة حرارة الحرق تشير عموما" الى زيادة معدل االتكثيف مع زيادة درجة حرارة الحرق، رغم ذلك، عندما تكون نسبة المواد الصلبة عالية نسبيا" فاءن اللزوجة تزداد عند الدرجات الحرارية العالية (حوالي 1400سo ) يعزى ذلك الى عملية نمو بلوري محتملة، وعلية يؤدي ذلك الى نقصان معدل االتكثيف. النتائج من برنامج تاثير زمن الحرق تشيرالى ان النموذج المطوريتنبا بزيادة شبة لوغارتمية للكثافة النسبية مع الزمن، بينما يتنبا النموذجان الاخران ( نموذج الكرة المركبة ونموذج المكون الذاتي) بزيادة اسية للكثافة النسبية مع الزمن. النتائج من البحوث السابقة تتفق مع توقع النموذج المطور. النتائج من برنامج تاثيرتوزيع حجوم المسامات على عملية التكثيف تدل على ان هذا العامل لة تاثير قوي عندما يكون التوزيع عريضا" فقط على المراحل النهائية لعملية التكثيف لان المسامات الكبيرة غلقها بطىء نسبيا". | A mathematical model describing the densification process during viscous sintering process of a material contains solid inclusions is developed (modified) from a Scherer model which describes the rate of densification during sintering for a free solid inclusions material. The modified model is used to simulate the rate of densification during sintering process for ceramic heterogeneous materials consist from mixtures of some Iraqi clays that had been prepared in a previous work. In addition the modified model is used to study the effect of several factors on densification during sintering process and used in predicting the effective viscosity of the viscous phase that formed during sintering. The factors are the sintering temperature, sintering time, and the ratio of solid inclusions volume to viscous phase volume.Another two heterogeneous models which are the composite sphere and the self consistent models are also applied and used to study the effect of sintering temperature and sintering time on densification during sintering for comparison with the present developed model.The modified model is also used to study the effect of pore size distribution on densification process by assuming a Gaussian distribution for the pore sizes and reformulating the equations of the modified model to make them depend on the standard deviation of pore size distribution.The physical parameters like viscosity are computed from the fitting process of the practical data of the samples.Computer programs in FORTRAN 90 language are designed to study the effect of sintering temperature on densification process using the developed model, the composite sphere and the self consistent models. These programs are modified to simulate the densification process versus time duration of the sintering process. Another program is designed to study the effect of pore size distribution on sintering process using the developed model. The results from the developed (modified) Scherer model are better fit the practical data, then the composite sphere model. The results from the program of the effect of sintering temperature indicates in general that the rate of densification is increased with increasing sintering temperature, this is due to the decrease in the viscosity with temperature increasing. However, when the ratio of the solid inclusions is high the viscosity is increased at relatively high sintering temperatures (about 1400oC) this increase in viscosity may be due to induced crystallization processes, accordingly the rate of densification is decreased at these circumstances.The results from the program of the effect of sintering time indicate that the modified model predicts that the increase in density is semi logarithmic with time, while the other two models predict an exponential increase with time. The results from the program of the effect of pore size distribution indicate that this parameter has a strong effect if the distribution is broad only in the last stages of densification because the largest pores are relatively slow to close

دراسة تاثير المحاليل الالكتروليتيه على خواص العزليه الكهربائية للبورسلين المشكل من مواد محليه == A STUDY OF THE EFFECT OF ELECTROLYTE SOLUTION ON THE PROPERTIES OF ELECTRICAL INSULATOR PORCELAIN FORMED USING LOCAL MATERIAL

Author name: عتاب فاضل حسين
Supervisor name: فاضل عبد رسن | ازهار جواد داوود
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: يهدف البحث الى دراسه تاثير المحلول الالكتروليتي ونسب تركيزه على الخواص الكهربائية والفيزيائية لجسم البورسليني الذي تم تحضيره باستخدام مواد محليه عراقيه. تم تشكيل الجسم بور سليني من كاؤلين دويخله،رمل زجاج ارضمه، فلدسبار وبنسب وزنيه (45 %, 30% , 25%) على التوالي. ولقد اجريت معامله كيميائية لكل من الكاؤلين والسليكا بهدف تنقيتها من الشوائب التي يمكن ان تذوب بحامض الهيدروكلوريك حيث تمت دراسة التغيرات الحاصلة من خلال تحاليل . IR قسمت الدراسة الى سبعه مجاميع محضره من هذه المواد طبقا لنسب المضافة من المحلول الالكتروليتي المحضر من (NaCO3+NaSiO3) وبنسبه (2 : 1) ان نسب اضافات المحلول الالكتروليتي هي 0.7%,1%) ,0.5% 0.2% , 0.1%) حيث ثبت نوع ونسبه الماده المعدنه في تشكيل الجسم البورسليني وهي او كسيد الزنكZnO وبنسبه (.(2% تم تشكيل مكبوسات من هذه الخلطات وبعد التجفيف تم حرقها لدرجات حرارة مختلفة1350oC) (1250, 1300 اجريت القياسات العزليه الكهربائية (ثابت العزل ومعامل الفقدان العزلي) وكذلك التوصليه الحرارية وقابليه الانضغاط. ان النتائج المتحققة لنماذج المحروقه بدرجه 1350oC ا بد ت نمط من ثبوت قيم العزليه الكهربائيه عند حدود معينه من تراكيز المحلول الالكتروليتي المضاف لمكونات الجسم البورسليني ضمن مدى((0.2 - 0.1% , في حين هنالك تغير في قيم التوصليه الحراريه ضمن مدى (0.2 - 0.5%) من تركيز المحلول الالكتروليتي. وان قابليه الانضغاط تكون عاليه عند حدود (0.5%) من تركيز المحلول الالكتروليتي لنفس المكونات،وبالتالي يتطلب اعتماد مفاضلة في الخواص وحدودها لاختيار افضل تركيز المحلول الالكتروليتي بما يوفر توافق نتائج الخواص العملية مع الخواص الصناعية القياسية المتحققة على منتجات محضره من مواد بلدان اخرى ومعتمدة لديهم ، لقد تم اعتبار ان افضل تركيز يتوافق مع الخواص العزليه الكهربائية وكذلك التوصليه الحرارية والميكانيكية هو (0.2%) كما اشاره اليه النتائج. | This study was carried out to prepare a porcelain samples, which can be used as an electrical insulator. The raw materials used for the preparation are kaolin Duakhla, Arudhma Sand glass and Potash feldspar with weight percentage (45%, 30%, 25%) respectively. A chemical treatment was performed on kaolin Duakhla, Arudhma Sand glass to remove all the impurities. The effect of the washing by HCl acid (chemical treatment) was examined by IR Tech. The study divided into seven groups. Relating to the concentration of electrolyte solution which is consisting of (NaCO3 & NaSiO3) as a ratio (2 : 1), and for fixed percentage of mineralizer (2%ZnO). The concentrations of electrolyte which were added to these groups are (1%, 0.7%, 0.5%, 0.2%, and 0.1%). Samples of each group have been prepared, and then each sample was pressed, then after that these samples are dried and sintered for different temperatures (1250, 1300, 1350 oC). Dielectric measurement (Dielectric Constant& Dielectric loss index) were carried out for these pressed samples, also Physical properties “Thermal conductivity” and mechanical properties “Compression strength” were measured for these samples. The results of these measurements for samples sintered at 1350oC are found to have a stable change at the range (0.1 - 0.2%) of concentration of electrolyte solution. While there is a change in the results of thermal conductivity in the concentration range (0.2 - 0.5%) of electrolyte solution. And the values of compression strength is found to be high at 0.5% concentration of electrolyte solution. Therefore we should select the best concentration of electrolyte solution, to get the optimum properties which would agree with practical results and the standard properties for the attentive in other countries of the world. Then, can regarde the (0.2%) concentration of electrolyte solution is the optimum value that can be used in the industry of the electrical insulators

دراسة النشاط الاشعاعي الطبيعي للمخلفات النفطية == A study of the natural radioactivity of thepetroleum waste

Author name: عصام محمد رشيد درويش
Supervisor name: ندى فاضل توفيق | كريم خلف محمد
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 to detect the radioactivity of radionuclides and measure the specific activities and the uranium concentration in (30) samples of crude oil and oil waste were brought from three oil locations Dora refinery, Bijie refinery, and north field of al - Rumaila. The measurements in this study were done by using two techniques : 1 - Gamma rays spectroscopy system was used to measure the specific activity for radionuclides. This system is consist of high purity of germanium detector (HPGe) with personal computer as multi channel analyzer (MCA) that computerized to plot the radioactive spectrum and compute the specific activities of the radionuclides. There are seven radionuclides are detected : (Bi - 214, Ra - 226, TI - 208, Bi - 212, Pb - 212, K - 40, and Cs - 137), these radionuclides included; two radionuclides (Bi - 214,Ra - 226) belong to the U - 238 series, three radionuclides (TI - 208, Bi - 212, Pb - 212) belong to Th - 232series, one natural radionuclide (K - 40), and one artificial radionuclide (Cs - 137).For Dora refinery samples, the averages of specific activities of (Bi - 214, Ra - 226) were (7.79, 16.08) Bq/kg respectively, the averages of specific activities of (TI - 208, Bi - 212, Pb - 212) were (7.95,4.05,5.75) Bq/kg , the average of specific activities of (Cs - 137) was (0.64) Bq/kg , the average of specific activities of (K - 40) was (99.3) Bq/kg. For Bijie refinery samples, the average of specific activities of (Bi - 214)was (0.39) Bq/kg, the averages specific activities of (Bi - 212, Pb - 212)were (0.02,0.01) Bq/kg, the average of specific activities of (K - 40) was(2.28) Bq/kg , and three radionuclides (Ra - 226, TI - 208, and Cs - 137) werenot appeared in Bijie samples.2 - solid state nuclear track detectors technique (SSNTDs), the uraniumconcentration determined by using CR - 39 track detector and fissionfragment track technique, the nuclear reaction used as source of uraniumfission fragment is U - 235 (n - f) obtained by the bombardment of U - 235with thermal neutrons emitted from (Am - Be) neutron source with flux(5000 n/cm2.s) for seven days, the concentration were calculated bycomparison with the standard samples.The uranium concentration in Dora refinery samples were rangedbetween (0.95 - 3.34) ppm with average (2.03) ppm for solid samples and(1.25) ppm for liquid samples.The uranium concentration in Bijie refinery samples were ranged from(0.42 - 1.46) ppm with average (0.55) ppm in the solid samples and (1.24) ppm in the liquid samples.The uranium concentration in the north field of al - Rumaila samples were ranged between (1.78 - 6.35) ppm with average (3.37) ppm.From above results, we concluded that the maximum of uranium concentration was found in the north field of al - Rumaila in Basrah governorate, these results are agreement with the permissible limit from IAEA. The maximum of external equivalent dose rate from NORM in oil waste was found in the north field of al - Rumaila was (0.30) mSv/y less than the permissible limit from IAEA which is (1) mSv/y for the public.

حسابات عن الخواص البصريه لعدسه رباعيه الاقطاب كهروسكونيه ثلاثيه == COMPUTATIONS ON THE OPTICAL PROPERTIES OF A TRIPLET ELECTROSTATIC QUADRUPOLE LENS

Author name: اسراء لطيف محمد العميري
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: استعانه بطريقة المصفوفات الانتقاليه والحاسوب الشخصي فقد اجري بحث حاسوبي عن خواص نموذج مستطيلي يمثل المجال المحوري لعدسه ثلاثية كهروسكونيه رباعية الاقطاب، ان مسار حزمة الجسيمات المشحونه الماره خلال المجالات المستطيلية قد تم ايجاده بحل معادلة مسار الحركه بالاحداثيات الكارتيزيه اذ كتب برنامج حاسوبي لهذا الغرض. لقد حسبت الخواص البصريه للعدسة الثلاثية الكهروسكونيه بالاستعانه بمسار الحزمه على امتداد محور العدسه. وكتبت برامج حاسوبيه بفورتران ٧٧ لايجاد مختلف الخواص البصريه. وتم تركيز الحسابات على ايجاد الابعاد البؤرية ومعاملات الزيوغ الكروية في كلا المستويين الافقي والعمودي للمسار على امتداد المحور البصري. وقد اظهرت النتائج ان اختيار المعلمات الهندسية والتشغيلية يعتمد على وظيفة العدسه الثلاثية الكهروسكونية الرباعية الاقطاب في منظومة بصريه الكترونيه او ايونيه معينة.

دراسة الخواص الحراريه للاغشيه الرقيقه الذكيه نوع نيكل - تيتانيوم == Study of Thermal Properties of NiTi Thin Film Shape Memory Alloy

Author name: هديل ثامر خضير
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: سبائك ذاكرة الشكل (SMA) shape memory alloyاو ما يسمى بالمواد الذكيه هي نوع من السبائك المعدنيه التي تعاني تحولات طور من الاوستنايت الى المارتنسايت عند تعرضها الى حراره او اجهاد كافي للتحول ولها القدره على الرجوع الى نفس حالة الشبيكه قبل التحول عند زوال المؤثر .لقد تم التركيز في هذه الدراسه على الخواص الحراريه كمحاوله لفهم التصرف الذي يحدث في الغشاء الرقيق والذي يتمثل بكسر شريحة الفلم عند تسليط قيمه معينه من الفولطيه والتيار وعند قيمه معينه من حرارة الاساس . وقد اخترنا دراسة غشاء NiTi لان له دور مهم في التطبيقات الطبيه والصناعيه .لقد تم حساب التوصيل الحراري والسعه الحراريه لغشاء NiTi نظـريا وكذلك تم حساب التوصيل الحراري والسعه الحراريه للزجاج المستخدم كاساس للغشاء عمليا وبعدها تمت مقارنة نتاءج هذه الحسابات للغشاء والزجاج وتفسير سبب الكسر في شريحة الغشاء والذي تبين انه يحدث في الزجاج نتيجة للفرق الكبير في الخواص الحراريه بين الغشاء والزجاج وهذا بسبب عدم تحمل الزجاج للطاقه الحراريه العاليه الناتجه خلال عملية تحول الطور بين الاوستنايت والمارتنسايت في الغشاء الرقيق والتي تسلط على الشريحة الزجاجيه للغشاء. | Shape memory alloys (SMA) or intelligent material, which are also called smart material, are a group of metallic alloys that undergo phase transformation from Austenite to Martensite when heated or subjected to appropriate stresses. After cooling or removing the stress, they have the ability to remember their previous structure and return to it.The concern of this study is on the thermal properties of NiTi thin film and its substrate as an attempt to understand the behavior occurring in the thin film slide represented by breaking it at certain values of voltage, current and substrate temperature (Ts). We have selected NiTi alloy because of its important medical and industrial applications. Thermal conductivity and heat capacity of NiTi thin film have been calculated theoretically and the thermal conductivity and heat capacity of glass substrate are measured experimentally. The cause of breaking in the thin film slide is the result of large difference in the thermal properties represented by thermal conductivity and heat capacity between the NiTi thin film and glass substrate. This is because the glass can not bear the high amount of heating energy resulting during the phase transformation process between Austenite and Martensite which exerts on the thin film slide

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.

حسابات الامثليه لمنظومة حرف الحزمة الالكترونية == A COMPUTATIONAL OPTIMIZATION OF AN ELECTRON BEAM DEFLECTING SYSTEM

Author name: عدي علي حسين العبيدي
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 استخدام التقريبين التحليلي والتركيبي لطريقة الامثلية في الدراسة الحالية لايجاد التصميم الامثل للحارفات المغناطيسية والكهروسكونية التي تعطي اقل زيغ كروي ولوني. استخدم التقريب التركيبي في حسابات الحارفة المغناطيسية وتم استخدام ملف الانحراف ذو النير الراكب (saddle yoke deflection coil) مصدرا للمجال المغناطيسي، عدة نماذج لتوزيع المجال المحوري استخدمت في الحسابات وكذلك تم استخدام انموذج جديد تم اقتراحه في الدراسة الحالية. فكرة العدسة الشيئية المتحركة اعتمدت في حسابات مجال الانحراف، زيوغ الانحراف خفظت لكل انموذج لتوزيع المجال بتغيير شكل ملف الانحراف، حيث غير الطول والزاوية. باستخدام امثل توزيع للمجال المحوري لكل حالة تم ايجاد تصميم قطع القطب التي تعطي توزيعات المجال هذه باستخدام طريقة اعادة البناء.في حسابات الحارفة الكهروسكونية، كل من التقريبين التحليلي والتركيبي استخدما لايجاد التصميم الامثل الذي يعطي اقل زيغ. تم اولا، استخدام التقريب التحليلي لدراسة بعض تصاميم الحارفات الكهروسكونية والتي تتكون من صفيحتين متوازيتين؛ الوصول للامثلية تم بتغيير الشكل الهندسي للحارفة عن طريق تغيير ابعاد الصفائح المتوازية. ثانيا، التقريب التركيبي استخدم لايجاد اقل قيم للزيغ باستخدام توزيع جديد اقترح في الدراسة الحالية للحارفات الكهروسكونية تحت البحث. شكل الحارفة تم ايجاده باستخدام طريقة اعادة البناء.اخيرا، الحارفات المغناطيسية والكهروسكونية جمعـت وركبت لتعطي عامود كامل لانظمة الانحراف ورسمت مقاطع مستعرضة لمسارات الحزم.

الميكانيك الاحصائي والخصائص الثرموديناميكية لتكاثف بور - اينشتاين في الاوساط الكسورية == Statistical Mechanics And Thermodynamic Properties of Bose - Einstein Condensation In Fractal Media

Author name: ابراهيم عبد المهدي صادق
Supervisor name: محمد عبد الزهرة حبيب | اياد عبد العزيز عباس
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 phenomenon of Bose - Einstein condensation (BEC), which was predicted by Einstein in 1925 and experimentally realized in 1995, has been the subject of intensive research in the last decades. On the theoretical side, several approaches have been formulat

بناء نموذج رياضي احصائي لطاقة الرياح في العراق باستخدام دوال مختلفة لتوزيع ويبل == Construction of Mathematical - Statistical Model of Wind Energy In Iraq Using Different Weibull Distribution Functions

Author name: فراس عبد الرزاق هادي
Supervisor name: اياد عبد العزيز العاني | محمد احمد صالح
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: في السنوات القليلة الماضية، شهد العالم اندفاعا نحو استخدام مصادر الطاقة النظيفة والمتجددة من اجل التقليل من التلوث البيئي وتكلفة الطاقة واستهلاك الوقود. لذلك انصب هذا العمل نحو قطاع مهم من قطاعات الطاقةالمتجددة وهو طاقة الرياح، حيث تم تقسيم العمل الى ارب | In the past few years, the world has witnessed a rush towards the use of clean renewable energy sources in order to reduce environmental pollution, energy cost, fuel consuming. Therefore, this work focused toward an important sector in renewable energy, w

الخواص التركيبيه و ميكانيكيه التوصيل المستمر و المتناوب للاغشيه الرقيقه 1-XSeX Cd المحضره بطريقه التبخير الحراري == structurl , D.C , and A.C. mechanism for thermally evaporated CdxSe1-x thin films

Author name: صبا نشات سعيد
Supervisor name: عزت محمود العيسى | طالب سلوم حمادي
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تحضير وتوصيف المركبات الفيروكهربائية BaxSr1-xTiO3 == Preparation And Characterization Of Ferroelectric Compound Like BaxSr1 - xTiO3

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:

التمثيل الحاسوبي للهوائيات ذات الاشكال الكسورية == Computer Simulations For Fractal Shaped Antennas

Author name: ملك عبد الحسن محي
Supervisor name: محمد عبد الزهرة حبيب
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

تحديد تركيز اليورانيوم في الادرار البشري لبعض المناطق المنتخبة في العراق باستعمال تقنية تحليل الفسفرة المستحثة بالليزر وتقنية كاشف الاثر النووي CR-39 == Determination Of Uranium Concentration In Human Urine For Selected Regions In Iraq Using Laser - Induced Kinetic Phosphorimetry And CR - 39 Nuclear Track Detector

Author name: احمد فرج صالح الجبوري
Supervisor name: مازن مانوئيل الياس | ندى فاضل توفيق
General topic: Physics
Specific topic: Applied Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

الدراسة الحسابية لعدسة وحارف مغناطيسي ذو توزيع جهد يخضع للعلاقة B(z) z-n == Computational Study Of Magnetic Lens And Deflector With A Field Distribution Of The Form B(z) ? z - n

Author name: بهاء عبد الحسن جواد
Supervisor name: اياد عبد العزيز العاني | عدي علي حسين
General topic: Physics
Specific topic: Physics
Degree: Master
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:

دراسة تاثير المضافات الثلاثية في الخواص الكهربائية لمركبات تايتانيت الباريوم == A Study Of The Effect Of Ternary Additives On The Electric Properties Of Barium Titanate Compounds

Author name: اثيل محمد جاسم الشالجي
Supervisor name: Fadhil Abd Risan | Ahmad K. Ahmad
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
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