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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.

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 نظرية لطاقة الترابط لذرة الليثيوم

Author name: محمد عبد الحسين حسوني وادي الكعبي
General topic: Physics
Specific topic: Physics
Degree: Master
University: University of Kerbala - College Of Science - Physics Department
Language: English
University location: Karbala
First pages:

تحديد النشاط الاشعاعي للنظائر المشعة 137Cs,134Cs,I131,40Kفي الاغذية المستهلكة في مدينة البصرة جنوب العراق == Radiation activity determination of 137Cs,134Cs,I131,40K and in food consumed in Basrah South of Iraq

Author name: مروة جواد كاظم راضي
Supervisor name: عبد المنعم خليل الكامل | علي عبد عباس الربيعة
General topic: Physics
Specific topic: Nuclear and Environmental Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:
Abstract: SAM 940TM detector has been used to detect and identify the radioactive isotopes (Radio - Isotope Identification (RIID)) at low levels of gamma rays emitted from food materials.Six samples of fresh milk have been pick out for six locations in Basrah. Ten samples of imported milk powder have been taken into account. Ten samples of lentils, rice, coffee and tea have been taken into account.Eight samples of mineral water, one of distilled water and one sample of piped water; the last one has been picked out from the net distributed water at physics department building in college of science university of Basrah.The results of our study show that, the annual effective dose for the radioactive potassium ????40 in food materials of the highest value. For local fresh milk is (0.216,0.529)mSv/y for adults and children respectively. It is of these samples have been taken from Zubair city, and its less value is (0.076,0.186)mSv/y for adults and children respectively. These samples have been taken from Abuo Al Kasseb. As for the imported milk powder, the highest value is (0.556,1.349) mSv/y for adults and children respectively. The sample is related to Al - munash milk from New Zealand, and less value is (0.272,0.660)mSv/y for adults and children respectively. The sample is related to modhash imported milk powder from Oman.For rice, the highest value is (0.303,0.636) mSv/y for adults and children respectively. The sample is related to Mahmood rice from India, and less value is (0.149, 0.313) mSv/y for adults and children respectively. That is for Galaxy rice imported from India.As for lentils, the highest value is (0.029 ,0.061) mSv/y for adults and children respectively. The sample is related to Wade al akdar lentils from Syria, and its less value is (0.020,0.042)mSv/y for adults and children respectively for Urbak lentils imported from Tukey. For water, the highest value is (0.189, 0.398) mSv/y for adults and children respectively for distilled water and Janaan drinking water from Baghdad. Its less valueis (0.183, 0.385)mSv/y for adults and children respectively for Aquafina drinking water imported from Kuwait.For coffee, the highest value is (0.041) mSv/y for adults for two samples from Brazil and one sample from Spain and other produce from Poland. Its less value is (0.019)mSv/y from European Union production. For tea, the highest value is (0.019, 0.039) mSv/y for adults and children respectively for Jant almunaash and Gazalian samples tea, its less value is (0.008,0.015)mSv/y for adults and children respectively for Alwaza, Mahmood and Baiet alteb samples tea imported from Sri Lanka.The annual effective dose of Iodine ????131 , Cesium ????????134 and Cesium ????????137 in lentils, rice, coffee, tea, mineral water, distilled water and piped water have been carried out and the results are listed in thesis.

درجة الحرارة المميزة وطاقة الاثارة الدنيا لليزر النقطة الكمية الشبه الموصل == Characteristic Temperature and Lowest Excitation Energy of Semiconductor QD laser

Author name: غيث منور علي
Supervisor name: رائد محمد حسن
General topic: Physics
Specific topic: Laser Physics and Electro-optics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: In this work, we have studied important theoretical relationships in Semiconductor Quantum Dot Laser (QDL) Characteristics.The study is based on theoretical model equations that are derived from the rate equations. The equations were applied on experimental parameters of continuous - wave QDL GaInP/InP at 1.55μm wavelength to get theoretical simulation of the characteristics of this laser type.We also studied the temperature effect on the internal losses and the impact of these losses in determining the characteristics of the temperature of QD. The results were presented within two cases; the first is when there are no internal absorption losses and the second where there is no existence of these losses. Also, we studied the effect of ambient temperature on the characteristics of temperature for each of QD and OCL.The lowest excitation energy of QD has been studied in two control cases : with surface density of QD and with cross - section of internal losses.Throughout changing many systems and control parameters, the effects of these parameters have been studied according to the different kinds of relationships. In this research, we have studied the parameters : Surface density of QD, mean size of QD, optical confinement layer, radiative constant for OCL material, spontaneous radiative recombination time, root mean square of QD size fluctuations, cavity length and mirrors reflectivity.Some of the results in this work were compared with other experimental results of other researchers who applied the QDL model and showed a good matching.

التقنين الاشعاعي البيئي للمياه الجوفية في غرب محافظة البصرة باستخدام تقنية التالق الحراري == Environmental Radiation Dosimetry of Groundwater in West of Basra Governorate using Thermoluminescence Technique

Author name: سيف قاسم هلال
Supervisor name: رياض جاسب ابو الهيل
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: This study includes calculation the dose rate of emitted gamma - rays from groundwater taken from different locations in the Basra govemorate by use of thermoluminescence technique . it emphasis on the the characteristics of TL - reader ,TL - dosimeter (calcium fluoride) to know the suitability of these systems for environmental monitoring. It is found that the zero dose reading for calcium fluoride is 0.18 m rad .It is also found that most dosimeters of the same materials have nearly equal sensitivities and that all thebatches have high uniformity which makes them capable for environmental use. Experimental observations have indicated that there is linear relation between response and dose for the material which qualifies it for measuring doses within the low dose range. The variations in the response of the TL - reader using internal light source have also been investigated ,it is found that TL - reader has high stability .The fading in a environmental field for calcium fluoride is 7% in one month.Making sure that these systems are suitable for environmental monitoring programing ,calcium fluoride has been used for measuring gamma - rays emitting from natural background radiation ,it is foundthat the natural dose rate of gamma - rays emitted from the locations : Albrjisiya, khor aizubair, Safwan, Jabal Sanam, Um Qasr, Um Eanij and Al - lahees are (5.80,6.41, 5.32, 5.25,5.26,4.60 and 4.86) μrad/h receptivity . Thus, the dose rate of radiation emitted From ground water of province of Basra is 5.35 μ rad/h . the results proved that the inhabited area ling within the environmental monitoring satiations are the area in which the radiation is natural and that the rate that the human being exposed equal 11.5μrad/h which considered naturalexposure limit.

تحضير وتشخيص بعض البلورات السائلة وخلائطها الثنائية البلورية السائلة ودراسة بعض خواصها الفيزيائية == Preparation & Characterization of some liquid crystals and Binary liquid crystalline mixtures and study some of their physical properties

Author name: زينب نديم مطشر
Supervisor name: اياد جاسم الحجاج
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:
Abstract: study included as a first step the preparation of compound 4 - heptyloxy benzaldehyde and derivatives by linking alkoxy series with the aldehyde, and in the second step was to prepare Schiff base compounds through interaction of equal moles of the compound 4 - heptyloxy benzaldehyde with some primary amines with different polar groups, and in the third stage was to prepare mixtures from the Schiff base compounds resulting from the second step,and we obtained five liquid crystalline mixtures at low temperatures and some of them close to room temperature, and then the chemical structures was chacterized and the absorption bands for functional groups was given by FTIR spectroscopy scan . A microscope with polarized light (POM) and a differential scaning calorimeter (DSC) was also used to study the liquid crystalline phases for individual compounds, as well as binary liquid crystalline mixtures and then a discussion of changes taking place at phase transition temperatures for individual liquid crystalline compounds as well as their binary mixtures , as characterized by these mixtures it owns a wide range of temperatures and some are close to room temperature ranging between (22.1 - 53.1 ℃). we has been studying some of the physical properties of these mixtures and compare them with the pure liquid crystals to see what has been achieved to improve these properties by studying the electrical properties (conductivity and dielectric ), as well as the activation energy , we has also been studying the photoelectric effect and determine the threshold voltage in the cases of parallel and vertical alignments , and the study shown a variation in the dielectric behaviour of binary liquid crystalline mixtures of remarkable increase compared to individual liquid crystalline compounds either the positive or negative dielectricanisotropy , ranging from ( - 1.320 - 2.234), while the variation in the electrical conductivity of binary mixtures of liquid crystal range (0.138 - 0.351 (ohm.m) - 1, and finally studied photoelectric effects for individual liquid crystalline compounds, as well as binary liquid crystal mixtures show that liquid crystalline mixtures have seen a clear decline in the threshold voltages (1.3 - 3.9Volt

دراسة نظرية لانتشار نبضة كاوسية في الياف البلورة الفوتونية والعوامل المؤثرة فيها == Theoretical Study of the Propagation Gaussain Pulse in Photonic Crystal Fibers and the Parameters Influencing it

Author name: دعاء حسين هاشم
Supervisor name: حسن عبد الله سلطان
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: In this thesis the propagation of short Gaussian pulse in Photonic Crystal Fibers (PCFs) are studied, the effect of the fiber parameters on the pulse like the absorption, dispersion and nonlinearity studied also.Nonlinear Schrodinger Equation (NLSE) was solved numerically using the spectral or Split - Step Fourier Method (SSFM) to determine the pulse spatio - temporal evolution.The study includes the effect of the photonic crystal arrangement especially the holes number, hole - hole spacing and holes dimeter on the effective refractive index and the dispersion of the photonic crystal fiber.The Nonlinear Schrodinger Equation (NLSE) was solved using the Finite differences in the frequency domain (FDFD) method.The two zeros dispersion were studied to calculate the zero dispersion wavelength (ZDW) by applying the international golden ratio (1.16180339887) for the ratio of the hole - hole spacing to the holes dimeters.The study shows that the pulse propagation depends strongly on the absorption, dispersion and nonlinearity of the PCF, and the pulse wavelength must be near the ZDW to ensure the propagation with little loses.The dependence of the nonlinear refractive index, the dispersion and the ZDW of the PCF were proved.The study shows that the golden ratio can be used to have two ZDWs, and a new ratio of hole - hole spacing to the hole dimeter equal to 2 can be used to achieve two ZDWs.

حساب كثافة الحاملات في طبقة الحصر البصري واشغال الحاملات المحصورة في منظومة ليزر النقطة الكمية نوع GaInAsP/InP == Calculating the Carrier Density in OCL and Confined Carrier Occupation in Quantum Dot Laser System Type GaInAsP/InP

Author name: ایمان ذیاب شرشاب
Supervisor name: رائد محمد حسن
General topic: Physics
Specific topic: Laser Physics and Electro-optics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: In this work, we have studied many control parameters effect which plays an important role to determine the density concentration of carriers in the Quantum Dot Laser (QDL) system. Our study is based on theoretical model equations which derived from the rate equations. The equations were applied to the GaInAsP/InP QDL with wavelength 1.55μm. We produce a theoretical simulation and analytical solution of the equations by a Mathematical program.Theoretical equations are used to study the effect the parameters by controlling the value of each : the carrier's density and occupancy of the Level of a carrier confined in a QD. There are two cases : when the cross - section of the internal absorption losses has a influential amount and a nather it case when approaching zero border. As well as, we study the impact of the parameters on the threshold current density and its compounds. In addition, we study the role of these parameter to determining the maximum temperature of QDL operation through effect on temperature rang of the system.The temperature effects on the carriers’ activities in the system are studied, whereas the characteristics temperature of QDL has been studied in the two cases : with / without internal losses.The effects of structure and control parameters are applied to Study many factors. Such as : surface density of QD, mean size of QDs, optical confinement layer, spontaneous radioactive recombination time and resonator losses.

دراسة تاثير جهود المصيدة على سلوك الدالة الموجية في تكثيف بوز اينشتاين == Study influence of the trapping potentials on the behavior of the wave function in Bose - Einstein condensation

Author name: وليد حميد عبد المالكي
Supervisor name: خالد محمد جياد الموسوي | خالد محمد جياد الموسوي
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:
Abstract: This dissertation have been studied and analyzed the wave function behavior under trapping potentials that are usually used in experiments which led to formed Bose - Einstein condensation in ultra cold gases. The wave function behavior is dealt with under the effect of three types of potentials : the Harmonic oscillator, the double well, and the Optical Lattice. These are used individually, overlapped together, and when two different kinds are shed on each other in an orthogonal form. Besides, factors and variables that have major or minor roles in potentials the distribution that determine the wave function behavior is discuss in this dissertation.And study parameter ???????? range of effect on the nature of the Harmonic oscillator trapping potential and the Wave Function distribution, this factor effect is studied under the effect of the Harmonic oscillator Trap. As well as, studying this parameter effect on the Wave function behavior under the effect of other three types of potential traps used in Bose - Einstein condensation which are : the Optical Lattice potential overlapped with the Harmonic oscillator potential, the Optical lattice potential orthogonally shed on the harmonic oscillator potential. Also, studied the wave function behavior under the effect of the double well potential when the range of distribution centre is ∓0.5 and when the distribution centre increases to ∓2.And also discussed the effect of the nonlinear G on the wave function behavior under the effect of the Harmonic potential in terms of value and distribution. Through studying under the effect of the Harmonic potential, it have noticed that there is a linear relation between the energy and the chemical voltage at the centre of the trap as well asbetween the wave function and Energy. Yet, the linear relation is not exist between Energy and the frequency rate ???????? as well as between the wave function and the chemical potential. While there is a nonlinear relation exist under the effect of the optical lattice potential overlapped with the Harmonic potential at the centre of trap as well as the relation is exist between the wave function and the energy at the centre of the trap. It is noticed that when the optical lattice potential orthogonally shed on the Harmonic potential a linear relation exists between the energy and the chemical potential with anisotropy value and this linear relation becomes more clear at high value of anisotropy while the wave function behavior increases exponentially with anisotropy values. Furthermore, we have studying the effect of Factor ???????? and Factor ???????? on the Wave Function behavior under the harmonic potential trap plus the optical lattice potential .

دراسة مقارنة بين ليزرات الابار الكمية والنقاط الكمية == Comparative Study Between Quantum Wells and Quantum Dots Lasers

Author name: وطن حمود جبر
Supervisor name: جاسب عبد الحسين مشاري
General topic: Physics
Specific topic: Laser Physics and Electro-optics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: In the work we present a comprehensive comparison between the dynamics of quantum well and quantum dot semiconductor lasers working autonomously using two models, the first describe the temporal variation of carriers and photon densities respectively in the quantum well lasers and the second describe the carriers occupancies in the wetting layer and quantum dot and photon occupancy in the quantum dot lasers .The study was carried out on the delay time and level of the dc part of their power under the effect of the many parameters that appeared in those models. Both lasers dynamics were studied in the presence of injection current modulation which enhances lasers power range from periodic to chaotic one with varieties of periodic states such as period.1, period.2, period.3, period.4 and period.6. Developed chaos was noticed to occur.We propose and investigate a simple method to obtain complex output power from both lasers via pulse shaping of the injection current. During the three methods studied we noticed similarities and discrepancies in both lasers dynamics.

دراسة تاثير ليزر النديميوم ياك (Nd+3 : YAG) النبضي على خلايا دم الانسان خارج الجسم == Study ofQ - Switched Nd+3 : YAG Laser Effect on Human Blood Cell in Vitro

Author name: منى جبر لفتة
Supervisor name: حسن حمادي محمد | مزاحم محمد عبد الله
General topic: Physics
Specific topic: Life Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:
Abstract: Nd+3 : YAG laser wavelength(1064)nm and the two other wavelength, namely λ=532nm and λ =355nm,were used. Many blood sample groups were exposed to these laser wavelengths to study the physical and biological effects appeared as a result of interaction of laser beams with human blood cells. Variable energy densities of these laser wavelength extended from (53.11mJ/cm2 to1990.45mJ/cm2) were employed in these experiments. Sixty human blood samples were collected which included mails with age between(20 - 35)years and weights between (60 - 75)gm. These samples were distributed into three groups : (a) The first group : Twenty human blood samples were exposed to laser (λ=355nm) with energy densities extended from (53.11mJ/cm2 to 1328.18mJ/cm2). The exposure time was fixed to (100sec) and the laser repetition frequency was (5Hz).White blood cells were counted before (control sample) and after laser exposure. types of WBC revealed, fluctuation in the count rates which didn’t reach the level of significant effect. The red blood cells results revealed a numerical changes in the Packed cell volume (PCV) depending on laser power densities. These Changes indicate that the laser affected the cells visbility . On the other hand, The spectroscopic results have been influenced, the optical properties of hemoglobin blood. The decrease in absorbance of hemoglobin and oxyhemoglobin as a function of laser influence gives a further evidence of changes in optical properties as compared with the control samples.(b)The second group : These group samples were exposed to laser wavelength (λ=532nm) with laser, energy densities range extended from (79.62mJ/cm2

دراسة تاثير الترابط والقدرة الضائعة في الموجهات المترابطة على كفاءة المجمع - الموزع البصري باستعمال طريقة الفروقات المحددة == Study The Effect of Coupling and Crosstalk in Directional Couplers on The Performance of Multi / Demultiplexers Using Finite Differences Method

Author name: منصور حنظل منصور زغير
Supervisor name: صباح مهدي محمد امين
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Science
Language: Arabic
University location: Basrah
First pages:
Abstract: Directional couplers can be used to make important planar optical integrated circuits for optical communications, such as Mach - zehnder interferometers and wavelength division multiplexers. Wavelength division multi/demultiplexing of optical signals is an efficient means to increase the information density per fiber.Both the coupled mode theory and the FD numerical method are used in this study to analyze multiwaveguide DCs.In this thesis, we present an analytical expression for crosstalk of MWGDC based on relationship between the normal modes and local modes, where these modes are obtained numerically using FD mothed.Also, the mode field profile and their evolution along the structure are presented through the analytical expression and calculated numerically using FD method. With the help of this analytical expression, the input power can be controlled to be enter from a chosen hannel. This enable us to calculate the crosstalk that corresponds to a certain input channel.The transmission characteristics of a four channel multiplexer based on three MZI can be described in terms of the propagation matrices. In this study, the coupling coefficient of DC and the phase shift of MZI are treated to be wavelength dependent parameters. Crosstalk introduced by such process are also calculated.The transmission characteristics of three arm MZI as a DWDM is investigated theoretically by deriving the propagation matrix of 3WGDC using coupled mode theory. Thus, two parameters are introduced,  and  , as a designing controlling parameters for DWDM devices. By adjusting these parameters a DW DM devices can be presented.

دراسة نظرية للتركيب الالكتروني الحجمي والسطحي لسبيكة نصف هيوسلر FeCrSe والحد الفاصل (111) FeCrSe/GaP == Theoretical Study of the Bulk and Surface Electronic Structure of the Half Heusler Alloy FeCrSe and the Interface of FeCrSe/GaP(111

Author name: مظاهر حبيب جولان الاسدي
Supervisor name: Mudhahir H. Jolan
General topic: Physics
Specific topic: Physics
Degree: Master
University: University Of Basrah - College Of Education For Pure Sciences
Language: Arabic
University location: Basrah
First pages:
Abstract: قدمنا في هذه الدراسة ايضاحات مهمة حول الخواص المغناطيسية والتركيب الالكتروني في سبيكة نصف هيوسلر FeCrSe. وقد بينت النتائج ان FeCrSe هي مادة فيرومغناطيسية نصف معدنية عند ثابت الشبيكة المتوازن هو 5.506Å، وان العزم المغناطيسي الكلي المحسوب هو 2μB يخضع تماما لقواعد سليتر - بولنك. بالاضافة الى ذلك، بحثنا على نطاق واسع الخواص الالكترونية والمغناطيسية والنصف معدنية للسطوح (001) و(111) لسبيكة نصف هيوسلر FeCrSe والحد الفاصل مع القاعدة GaP (111) باستعمال حسابات المبادئ الاولية ضمن نظرية الكثافة الدالية. وتوضح كثافة الحالات الذرية ان الصفة النصف معدنية المثبتة في الحجم FeCrSe تكون محفوظة عند السطح (001) المنتهي بـ CrSe - والسطح (111) المنتهي بـ Se - ، ولكنها فقدت عند السطوح (111) المنتهية بـ Fe - وCr - والسطح (001) المنتهي بـ Fe - . علاوة على ذلك، للحد الفاصل FeCrSe/GaP (111)، تكون الصفة النصف معدنية للحجم محطمة عند الهيئة Se - P بينما يبين الحد الفاصل والحد الثانوي الفاصل Se - Ga تقريبا استقطاب برم 100%. ضمن هذه الدراسة اوضحنا، من حسابات طاقات التلاصق (γ) للحد الفاصل ان الشكل او الهيئة Se - Ga هو اكثر استقرارا من الاخر Se - P. وايضا درسنا العزوم المغناطيسية، فلاحظنزايادة العزوم المغناطيسية المحسوبة لـ Se وGa عند الحد الفاصل Se - Ga (111) وP عند الحد الفاصل Se - P (111) مقابل قيم الحجم المناظرة لها بينما العزم المغناطيسي الذري لذرة Se عند الحد الفاصل Se - P (111) يقل. ونلاحظ ايضا ان العزوم المغناطيسية للحد الفاصل الثانوي لذرة Fe عند كلا السطحين الفاصلين Se - Ga (111) وSe - P (111) تقل مقارنة بقيم الحجم. | In this study, important illustrations about the electronic structures and the magnetic properties of half - Heusler alloy FeCrSe.The results show that FeCrSe is half - metallic ferromagnet at equilibrium lattice constant (5.506 Å). The calculated total magnetic moment of 2.00 μB follows quite well the Slater - Pauling rule . We investigate extensively the electronic, magnetic, and half - metallic properties of the half - Heusler alloy FeCrSe (111) and (001) surfaces and the interface with GaP (111) substrate by using the first - principles calculations within the density functional theory. The atomic density of states demonstrates that the half - metallicity verified in the bulk FeCrSe is maintained at the CrSe - terminated (001) and Se - terminated (111) surfaces, but it is lost at both Cr - and Fe - terminated (111) surfaces and the Fe - terminated (001) surface. Furthermore, for the interface of FeCrSe/GaP (111), the bulk half - metallicity is destroyed at Se - P configuration while Se - Ga interface and subinterface show nearly 100% spin polarization. We explained within this study, the calculated interfacial adhesion energies exhibit that Se - Ga shape is more stable than the Se - P one. We also studied the magnetic moments, The calculated magnetic moments of Se, Ga at the Se - Ga (111) interface and P at the Se - P (111) interface increase with respect to the corresponding bulk values while the atomic magnetic moment of Se atom at the Se - P (111) interface decreases. We also notice that the magnetic moments of subinterface Fe at both Se - Ga and Se - P (111) interfaces decrease compared to the bulk values.
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