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

اسم المؤلف: احمد شاكر محمود ياس
اسم المشرف: محمد عبد الزهرة حبيب
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: مصطفى يوسف رجب
اسم المشرف: حسين علي الجبوري
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

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

اسم المؤلف: مروة جواد كاظم راضي
اسم المشرف: عبد المنعم خليل الكامل | علي عبد عباس الربيعة
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: 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.

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

اسم المؤلف: سيف قاسم هلال
اسم المشرف: رياض جاسب ابو الهيل
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: زينب نديم مطشر
اسم المشرف: اياد جاسم الحجاج
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: دعاء حسين هاشم
اسم المشرف: حسن عبد الله سلطان
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: 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.

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

اسم المؤلف: مظاهر حبيب جولان الاسدي
اسم المشرف: Mudhahir H. Jolan
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: 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.

دراسة نظرية لفحص نقل الالكترون خلال نقطتين كميتن مقترنتين == Theoretical Study to Investigate the Electron Transport Through Double Coupled Quantum Dots

اسم المؤلف: محمد عبد الزهرة نجدي
اسم المشرف: هيفاء عبد النبي جاسم
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: In this study, a model calculation is introduced for the electron transportthrough a system consists of two quantum dots coupled serially, embeddedbetween two nonmagnetic leads (source and drain), due to the importance ofthis kind of systems in many academic and experimental applications.In our treatment, the time independent Anderson - Newns Hamiltonian modelis considered as a basis to study the system dynamics and then to derive spindependentanalytical formula to calculate the occupation numbers of thequantum dots energy levels, the corresponding quantum dots energy levelsand the molecular virtual energy levels, as a function of bias voltage .These relations are solved self - consistently, which are all employed tocalculate the tunneling current. The differential conductance is calculatednumerically by using finite differences method.And as the efficiency of electron transport through coupled quantum dotsdepends on the system parameters such as the energy levels position of eachquantum dot, the Coulomb repulsion energy on each quantum dot, theeffective exchange energy, the tunneling coupling between the dots and leadsand the coupling energy between the two quantum dots, all these parametersare studied and investigated in details and the role of all these parameters inthe tunneling current and the differential conductance calculations ispresented. also our treatment is applied to two kinds of systems, when thequantum dots are symmetric and when they are asymmetric depending on ourchoice for the over mentioned parameters. Our treatment is utilized to studythe following : 1 - - - Two regimes are studied, the first is the strong coupling regime and thesecond is the weak coupling regime.2 - - - The role of the spin exchange interaction in determining the type ofinteraction (if it is attractive or repulsive) between the quantum dots.3 - - - The role of the spin exchange interaction between the quantum dots indetermining the coulomb blockade in the strong coupling regime.And according to our calculations, we conclude that at the strong couplingand when neglecting the effective exchange interaction, one can determinethe bias voltage values that correspond to the maximum values of thedifferential conductance which is equal to the value of the couplinginteraction between the quantum dots. And the maximum and minimumvalues in the differential conductance curve are changed when the quantumdots energy levels are lying below the energy reference. Also, ourcalculations that concern to the effective exchange interaction make it sure that our results can be utilized to study the electronics that related to the coupled quantum dots. Our calculations that related to the Coulomb blockade make it sure that one can use the quantum dots molecule as an electronic switch. Our calculations that concern to the gate voltage effect investigation in the case of equilibrium can be employed in the detection about the type of coupling with the environmental which effects directly in determining the rates of electron tunneling from the left lead to the active region and then to the right lead.

دراسة الخواص البصرية والكهربائية ومحدد القدرة البصري للصبغات العضوية المشوبة للاغشية البوليمرية == STUDY OF THE OPTICAL AND ELECTRICAL PROPERTIES,AND OPTICAL POWER LIMITING OF ORGANIC DYES DOPED POLYMER FILMS

اسم المؤلف: فيصل صادق ثامر
اسم المشرف: عماد الدين حسين علي السعيدي
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: This thesis contains results of a extensive study for many important and fundamental properties of two organic dyes, these are Phenol Red and Light Green SF Yellowish. To obtain the dye doped polymer films used for our study, the Polymethylmethacrylate (PMMA) polymer was doped by each one of these dyes , at different concentrations : 0.01, 0.02, 0.03, 0.04, 0.05, 0.30, 0.40 mM . Effect of adding small amount of Iodine (I2) , as a dopant, to the constituents of the dye doped polymer films at concentration of 0.03 mM for each dye, on the optical and electrical properties of the polymer films, was also studied. Casting method was used for preparing the dye doped polymer films samples.The present work involves the study of the linear and the nonlinear optical properties, and the optical power limiting of the dye doped polymer films, as well as study of the electrical properties of these films.We have studied the optical properties of both the dye - doped polymer films and the dye - doped polymer films with Iodine (I2). The study includes the following parameters : absorbance (A), transmittance (T), reflectance (R),iiabsorption coefficient (α), extinction coefficient (k), refractive index (n), dielectric constant (ε) with its real (εr) and imaginary (εi) parts, optical conductivity (σopt.), electrical conductivity (σelec.), and optical energy band gap (Eg).The results of the optical properties show that the dye - doped polymer films having high transmittance (T) , low reflectance (R) , and low absorption coefficient (α ) , over the wavelengths of the visible spectrum, and these films have energy band gaps belong to the indirect transitions. While the dye - doped polymer films with added different doping ratio of Iodine (I2), have low transmittance (T) and an increase in the values of reflectance (R) and absorption coefficient (α ), particularly in the absorption regions over the wavelengths near the ultraviolet (UV) region of the the electromagnetic spectrum.To study the nonlinear optical properties of the dye - doped polymer films, the laser beam z - scan technique was used with solid state laser (SSL) operating at the continuous wave (CW) at 532 nm. The laser output can be varied within the range 0 - 100 mW. The obtained results showed that the samples of the dye - doped polymer films as well as the samples of the dye - doped polymer films with Iodine(I2) have a nonlinear refractive index with negative value (n2 < 0) (occurrence of the self - defocusing effect) and aiiinonlinear absorption coefficient with negative value also (β < 0) (occurrence of the saturable absorption).We have studied the optical power limiting for the prepared films samples , using the laser beam z - scan technique. We have obtained optical power limiting with good optical properties. The results revealed that the smallest value for optical power limiting threshold is 15 mW for the Phenol red dye doped polymer film sample at concentration of 0.03 mM with Iodine doping ratio 36.2 % of the dye weight.Also, The electrical properties of the prepared samples, the dye - doped polymer films and the dye - doped polymer films with Iodine (I2), have been studied using the current - voltage (I - V) characteristic for three temperature degree values , which are given to these samples, these are : 298 K, 308 K and 318 K. The values of the electrical conductivity (σ) and the electrical conductivity activation energy (Ea) of polymer film were calculated. The influence of changing the temperature on these parameters was studied.The results obtained from the present our study indicate that the two organic dyes, Phenol Red and Light Green SF Yellowish, are good candidates for optical applications and they could be used for the photonic devices, the photo - electronic devices , and also in the optical power limiting

دراسة نظرية للخواص النووية للانوية السوجية - السوجية 198 - 208Po و200 - 210Rn و218 - 228Ra و218 - 228Th و226 - 236U ا بسثعمال انموذج البوزونات المتفاعلة بنسختيه IBM - 1 وIBM - 2 == Theoretical Study for the Nuclear Properties of the even - even 198 - 208Po,200 - 210Rn,218 - 228Ra, 218 - 228Th,226 - 236U by using the Interacting Boson Model IBM - 1 , IBM - 2

اسم المؤلف: علي فاخر حبيب
اسم المشرف: عبد الرضا حسين صبر
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: This work aims to study the details the nuclear structure of selected heavy nuclei 198 - 208Po ,200 - 210Rn, 218 - 228Ra, 218 - 218 - 228Th and 226 - 236U, due to the important of nuclear structure of these nuclei in applied nuclear physics. In this study two IBM version have been used, IBM - 1 and IBM - 2. The versions of model used to described the ground band, quizi - beta and quadruple reduced transition probability B(E2) for selected transition. Also, the IBM - 2 version has been used to calculate the magnetic reduce transition probability B(M1) and mixing ratio for group transition emitted from ground band, quazi - beta and quazi - gamma band . the mixed symmetry states and the effect of majorana parameters of the energy of these state have been studied extensively .the potential energy surface of each isotope has been produced as contour lines using the output of IBM - 1.From the result calculation it is found that there is an agreement between the available experimental data and the calculated results of both IBM - 1 and IBM - 2 . The agreement concerns the energies of ground band and less in the beta and gamma band for 198 - 208Po isotopes. Also we have agood agreement in values of B(E2) and B(M1) from the results of the two version. It is noticed that all the studied isotopes are belong to the vibrational U(5) limit.The result of 200 - 210Rn isotopes show closed to the vibrational U(5) moving toward the O(6) . the calculated values are very closed the experimental data for the positive parity states of the ground, beta and gamma bands with increasing of energy value near the closed shell.The variable position of 218 - 228Ra isotopes between the three limits of IBM - 1 ((SU(3), O(6), U(5)) ,where is; these isotopes moving towards rotational away from the closed shell . We notice the excellent agreement between calculated values and available experimental data for energy level and other nuclear properties. The value of E41/E21 for 218 - 228Th isotopes decreases with moving away from the closed shell, in the same time; the values of level energies decreases also. The agreement between the experimental and calculated values of energy level is very clear for energy level and B(E2) and B(M1) values.All studied 226 - 236U are belong to the rotational SU(3) limit and both versions of the model succeed in producing such limit and found agood agreement for all the bands specially the IBM - 2. It is found that the change in the Majorana parameter FS has an effect on the energy of the mixed symmetry state in studies isotopes . The B(E2) values also calculated and compared with experimental data.In the comparison between all the studied nuclei it is found that systematic of energy level of single nucleus and all isotopes it is found that the energy of the first excited state is different for such isotope and also the ratio of E41/E21 found to be moving toward rotational limit with increase of atomic number. In the present work we found that the ratio N/Z is always agree when we used different isotopes in the studied nuclei

تضمين البرم في ليزرات اشباه الموصلات (ليزرات البرم) == Spin Modulation in Semiconductor Lasers (Spin lasers

اسم المؤلف: ضیاء جبار عكوش
اسم المشرف: حسن عبد الله سلطان
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: The introducing of electronic spin with its charge is the key of many applications which uses the electrical and magnetic properties of the electron , (spintronics )and semiconductor lasers.This concept gives led to the newest type of semiconductor lasers called ( Spin Lasers ).In the present thesis a numerical study of the effect of the carriers spin on the semiconductor lasers described by VCSEL using Matlab and Runge - Kutta method .The study includes the effect of the spin polarization in terms of the polarization injection and the injection current also to find the two thresholds of right polarized light circularly and the left circularly polarized one.The effect of the spin relaxation time on the dynamics of spin - VCSEL such as the steady state time evolution and direct modulation of the injection current and the polarization injection were studied also is presented too.The study shows that the spin VCSEL strongly affected by the injection current , polarization injection and spin relaxation time.The present results show that the laser threshold can reduced to quarter than that of conventional laser.

تحضير اغشية رقيقة من اوكسيد الخارصين ZnO النقي والمشوب بالالمنيوم باستخدام تقنية المحلول ودراسة خواصها البصرية (Sol - Gel) الغروي وتطبيقها كمتحسس غازي == Preparation of Pure and Doped with Aluminum Zinc Oxide (ZnO) Thin Films by Using (Sol - Gel)Technique and the Study of Optical Properties and Applications as A Gas Sensor

اسم المؤلف: سعد عبد الله جبر الفاضلي
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: In this study, Zinc Oxide (ZnO) thin films are prepared by using Sol - Gel technique . The samples are prepared with different thicknesses (58,69,77)nm . Different weight ratio of Aqueous aluminum chloride (AlCl3.6H2O) are added to the Sol - Gel ZnOwith percentage (0.345%, 0.824% , 1.703% and 2.146%). These solutions are deposited by using spin coating on glass substrate .In order to investigate the sensitivity and the response of these samples for the detection about different vapors and gases (ethanol , methanol , acetone and nitrogen ) , pure and (AlCl3.6H2O) doped ZnO films are prepared by using the same technique but by adding Aluminum electrodes on these films with dimensions (2.5x0.5)cm2 .This preparing is followed by thermal treatment for these films by using oven with temperature reaches to 450 oC.The structure properties of these films are studied by using X - ray diffraction (XRD) and the results show that these films are polycrystalline and the calculated lattice constant are close to the standard values . The samples are analyses by Field Emission Scanning Electron Microscopic (FESEM) and the results show that the grain arrangement are regular and these structures are packed and the grain shape is as spherical . But for the AZO films , we notice that the increasing of the doping percentage reduces the gra in size .We also study the optical properties of these films such as Absorption (A) , Transmission (T) , Reflection (R) , Absorption coefficient (α) , extinction coefficient (k) , the energy gap(Eg) , refractive index (n) , with its complex and real dielectric constant( ) , dissipation factor (tanδ) , Optical Dispersion Parameters (Eo , Ed) and optical conductivity ( ) . The effect of the films thickness on the optical properties of the ZnO films for the over mentioned parameters . The results we get are discussed and compared with other studies . This work elucidates and analyzes the studying of the effect of adding (AlCl3 . 6H2O) o Zinc Oxide (ZnO) and the results are with standards agree with the results of many other researchers . The optical constant are tabulated and compared with , the results of other . And in order to determine the electronic transitions type , Absorption coefficient is calculated and it shows that ZnO and AZO films have transition of direct type because the values of α > 104 . The energy gap of the ZnO films with different thickness (58,69 and 77) nm is calculated , since it is found that the increasing of the film thickness gives slight increasing in the energy gap . The experimental results show that the increasing of doping percentagein ZnO film increases the energy gap with very little amount . In the electronic application field , the study also included design and fabrication of gas sensor system from local materials , which contain of chamber that made of plates polymer that contain of base for install the sample , electrodes to link the sample the measurement circuit , glass flask with three holes , heater , N2 gas cylinder , glass tubes , valves and the measurement circuit electric .The study also includes the ability of responding of the films for the thicknesses (58 , 69 and 77 )nm , to these gases , and it is found that the highest response was at vapor ethanol at the thickness 58nm. The effect of chloride Aluminum on the response of these percentage (0.345% , 0.824% , 1.703% , 2.146%) is studied for the mentioned gases , and it is found that the highest response we get is 45% at the concentration 2.146% for methanol gas . The results are tabulated , discussed and compared with precedent studies.

دراسة حركيات ليزر النقطة الكمية بوجود البرم == Study of Dynamics of Quantum Dot Laser with Spin

اسم المؤلف: حكمت عبد الحسين ابراهيم
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: The dynamics of VCSE QD spin polarized laser is studied based on asix equations model that takes into account the effect of number ofcontrol parameters on populations in the wetting layer for bothpolarized components and those in the quantum dot .The carrier density in the wetting layer and the quantum dot vary indifferent manner although the former lends to the later . Also thedynamics of carriers in the quantum dot shows varieties of dynamicsthat range from simple to complex one while the dynamics of carriersin the wetting layer are always simple .The polarized field related to the spin up and spin down cases sufferseffects in different manners due to the variations of these controlparameters . the intensities of both two polarized components behavioralso range from simple and end up chaotically.It appears that output ellipticity can be used as a new tool to assess the dynamical state of the laser wither it in stable , periodic , aperiodic or chaotic .The modulation of the injection current for both components or for either one led to new dynamics , the system was not able to show when it work autonomously although the model has five degrees of freedom .

خصائص نقل الالكترون العابر لانظمة نقاط كمية متعددة == Transient Electron Transport Properties of Multiple Quantum Dots Systems

اسم المؤلف: حسه ابراهيم عسكر
اسم المشرف: شاكر ابراهيم عيسى
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: فيزياء الالكترونيات
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: We presented a theoretical study for the electron transportcharacteristic, within a system of multi - quantum dots coupled tothe three metallic leads (right lead as an electron reservoir andtwo left leads as an electron source). We take into account twoarrangements for the scattering regions, one composed of twoquantum dots and the other is composed of four quantum dots.The study concentrated on the system parameters that has itseffect on the characteristic of the electron transfer process andhow these characteristic are affect by the number of the quantumdots in the scattering region in the both arrangements for thescattering regions.The theoretical formulism depends on the one - electron model.Where, we assigning a single effective level for each quantumdots and by taking the effects of the leads continuum levels intoaccount which are show within the wide band gap approximationto produce an imaginary quantity add to the energy levels of thequantum dots, representing the broadening in each effectivelevels.The related basic equation of motion for all the correspondinglevels eigen function probability amplitudes are solvedanalytically by using Laplace transform technique. We calculatethe occupation probability for the right lead, the instantaneouscurrent and the average instantaneous current that passes throughthe right lead.Our calculated results for the time - dependent dynamical electrontransfer offered a general features that takes into account thefollowing effects :  Energy levels position changes with respect to the leadFermi level. A suitable applied bais voltage on the right and left leads. Changes of the coupling amount among the quantum dots levels and in between them and the leads levels. Change of the leads temperatureThe characteristic of the time - dependent charge transport in the system are shown through the relation between the average instantaneous current passes the right lead and the applied baisvoltage, which we show as follow :  For the case of the scattering region arrangement that compose of two quantum dots it is an Ohmic behavior. For the case of the scattering region arrangement that compose of four quantum dots it is a non - linear (non - Ohmic) behavior.

دراسة تركيز البورون في مياه محافظة ذي قار وتربتها باستخدام طريقة الكارمين وجهاز اللوفي بوند == Study of Boron Concentration in Water of Thi - Qar Governorate and Soil Using Carmine Method and Lovibond Device

اسم المؤلف: تغريد عبد الحسين شاكر
اسم المشرف: ثائر منشد سلمان
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: In this study , we measured the boron concentration in the water and soil of Thi - Qar Governorates, where were collected (45) Sample Water also were collected (66) Sample soil from the districts of Thi - Qar and its environs province of southern Iraq , and we used that analogy chromatography Al carmine method (colorimetric carmine method) . we got the highest concentration of boron (0.801 ppm) in Garmat Bani Said area - Al Greej and the lowest value for the concentration of boron measured Al carmine manner of samples of clay in said Dhkeel - Al Ibrahim (2) area (0.368 ppm) . The concentration of boron has been in samples of mud rate in the province of Thi Qar was (0.614 ppm) also were measured exponent pH and ranged results between (7.208 - 8.368 ) and an average of (7.890) . As well as we used measurement chromatography Al carmine to measure the boron concentration in water samples way . We got the highest value for the concentration of boron water sample (1.057 mg / L) in Garmat Bani Said area - center (1) and the lowestvalue for the concentration of boron measured Al carmine way in water samples in Al Fuhood zone - Amayreh(1) (0.251 mg / L) . Boron concentration of water samples in the province of Thi Qar rat was (0.592 mg / L) .The boron concentration of water samples located within the normal allowable ratio globally but some are relatively high . As well as the measured pH and the results were pH ranging between (7.435 - 8.277) and an overall average of (7.885) .It was also some water samples to measure the soil by a device (Spectro Direct Lovibond) we got the highest value for the concentration of boron in the water samples (1.4 mg / L) in Al Fuhood zone - Amayreh area (3) , and the lowest value for the concentration of boron in Al Nasiriya - Al shuhada zone (1) (0.4 mg / L) . The soil samples were measured by a device (Spectro Direct Lovibond) has the highest value for the concentration of boron we got them in Al Tar - Al hareb area (1.1 ppm) and the lowest value for the concentration of boron in Al Tar - Al Ebrat (0.2 ppm) .

خصائص نقل الالكترون لكيوبت مقترن بترانزستور الالكترون المفرد == The Electron Transport Properties of Qubit Coupled with SET

اسم المؤلف: ايات طاهر ابراهيم
اسم المشرف: جنان مجيد المخ
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: فيزياء الالكترونيات
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: العربية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: In this work, the dynamics of electron transport through a system consists of qubit (two coupled quantum dots) electrostatically coupled with single - electron transistor (quantum dot coupled to leads). The time - dependent Hamiltonian, that is used to describe the system energy, includes the electrostatic coupling between the qubit and the single - electron transistor. The time - dependent equations of motion for all the creation and annihilation operators are expressed in Heisenberg representation to derive the differential equations of motion for the quantum dots occupation numbers of the qubit and the single electron transistor, the related equations of motion for the correlation functions and also the formula that calculates the current which tunnels from the left lead to the single - electron transistor quantum dot. The system of equations of motion are treated by using the wide band approximation, and are solved numerically by using six order Runge - Kutta method, where the error is calculated at each step of time. By getting use of the system of differential equations solutions, the qubit and the single - electron transistor quantum dots occupation numbers are calculated as a function of time, in addition to the current that tunnels from the left lead to the single electron transistor quantum dot as a function of time.The main goal of this study in to investigate the effect of the parameters that related to the qubit and the single - electron transistor and their role in determing the electron transport process features through the whole system. These parameters, that are related to the initialization, manipulation and measurement processes, are the qubit and the single electron transistor quantum dots energy levels, the coupling strength between the qubit quantum dots, the electrostatic coupling between thequbit and the single electron transistor in addition to the coupling strength between the single - electron transistor quantum dot and the leads as well as the leads properties such as tempreture and band width. The effects of quantum dots energy levels tuning and the symmetry of the coupling with leads on the electron transport through the system are also investigated.Our study highlights four important physical features that related to the initialization, manipulation and measurement processes, these are : 1. The occupation numbers of the quantum dots of the qubit and the single electron transistor and the current of SET at the final time of measurement.2. The charge accumulation on the qubit quantum dots, at the final time of measurement, on the far - removed quantum dot and the nearest one to the single - electron transistor, that can be controlled by appling bias voltage and gate voltage.3. The determination of the time - current dependence if it follows the dependence of the far - removed or the nearest qubit quantum dot occupation number on time.4. The role of qubit energy levels tunning and the asymmetric coupling with the leads in determining the suitable initialization and manipulation processes get the quantum measurement with high quantum efficiency.

دراسة نظرية وعملية لمعالجة الصور الطبية باستخدام تقنية فورير == Theoretical and Experimental Study on Coherent Processing of Medical Image Using the Fourier Optical Technique

اسم المؤلف: مروة كريم عبد
اسم المشرف: رياض ناجي علي
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بابل
الصفحات الاولى:
المستخلص: في هذا البحث تم اعتماد نظرية الحيود وتحويلات فوريير (بصريات فوريير) في معالجة الصور عمليا (باستخدام نظرية بصريات فورير) كمعالج بصري , ونظريا (باستخدام برمجيات MATLAB ) . استخدمت في البداية اجسام قياسيه ذات اشكال هندسيه منتظمة ( المربع والدائرة) ذات دوال رياضيه بسيطة في النطاقين الحيزي spatial domain)) والترددي (frequency domain) وذلك لسهولة المقارنة بين نتائج المعالجتين العملية والنظرية. بعد ذلك تم استخدام عدد الصور, اغلبها طبيه كونها الغاية الاساسية للبحث, كاجسام في منظومة فوريير المختبرية لمعالجة المعطيات البصرية . كجزء من متطلبات معالجة الاشارة البصرية استخدمت ثلاثة انواع من مرشحات الاشارة البصرية لثلاثة انطقه حيزيه مختلفة (الترددات العالية, الواطئة, وحزمه تردديه متوسطة). بينت نتائج الدراسة افضليه وبساطه المعالجة النظرية , باستخدام برمجيات ماتلاب بالقياس الى استخدام منظومه فوريير المختبرية, وبالتالي امكانيه استخدام هذه البرمجيات, مع البرمجيات المستخدمة في تناول الصور في اجهزة التصوير الطبي المختلفة, لاغراض التشخيص الطبي المحوسب | In this thesis, the diffraction theory and the Fourier transforms technique (Fourier optics) are utilized to coherently process the optical data experimentally and theoretically, through implementing Matlab software. Two standard objects of regular geometry (rectangular, and circular aperture functions) are used as diffraction apertures. Then their Fourier transforms and inverse Fourier transforms are obtained experimentally (by using 2F - & 4F - set up optical processors), and then calculated theoretically using Matlab. Many complex objects are used, especially medical images (the targeted aim of this project), are implemented and processed using technique. Different special filters (low - pass, high - pass, and band - pass) are used to manifest the main processing features such as enhancement, smoothing and edge detection. The results of this project show the superiority and simplicity of the Matlab software in processing the complex images. This proves the capability of implementing Matlab software, together with the medical imaging system's handling software, in computerized medical identification and diagnosis

دراسة انتقال طاقة الفلورة داخل جزيئات الوسط الفعال الليزري == Study of fluorescence energy transfer in laser active medium molecules

اسم المؤلف: نورة عزيز عليوي
اسم المشرف: لازم حسن عبود
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: بابل
الصفحات الاولى:
المستخلص: في هذا البحث تم دراسة ظاهرة انتقال طاقة الفلورة بين الصبغات الليزرية والتي تتحقق هذه الظاهرة بتساوي طاقة طيف الامتصاص لاحدى الصبغتين مع طاقة طيف الانبعاث (الفلورة) للصبغة الثانية في الحالة المثالية لحصول الانتقال, وهنا تسمى الصبغة الاولى بالجزيئة القابلة والصبغة الثانية بالجزيئة المانحة.وقد تم تحضير انموذجين في هذا البحث,الاول للصبغة القابلة وهي (الاكردين اورنج Acridin orang) مع الصبغة المانحة وهي (البوب بوب Popop ) والانموذج الاخر كانت فيه الصبغة القابلة (الاكريفلافين Acriflavin) والمانحة هي (البوب بوب).وعند قياس طيفي الامتصاص والفلورة لكلا الانموذجين تحقق التداخل الكبير بينهما وهذا يؤكد تحقق حصول نموذج (القابل - المانح).وقبل البدا بالخلط تم دراسة اطياف الامتصاص والفلورة وكذلك الخواص البصرية الخطية لجميع الصبغات المستخدمة على انفراد وبتراكيز مختلفة , وهي (0.5x10 - 3,0.5x10 - 4,1x10 - 5, 1x10 - 6)ML, وبينت النتائج تغير الطول الموجي لجميع الصبغات مع تغير التركيز وحصول زحف نحو الازرق مع زيادته ونقصان كل من معاملي الامتصاص والانكسار في التراكيز الواطئة ,مع ملاحظة زيادة الكفاءة الكمية ونقصان العمر الزمني لمستوي طاقة الفلورة مع نقصان التركيز.وبعد تحضير انموذجي (القابل - المانح) لصبغتي (الاكردين اورنج + البوب بوب)و(الاكريفلافين +البوب) وبالتراكيز السابقة نفسها ,لاحظنزايادة شدة طيف الانبعاث (طيف الفلورة) حيث كانت اعلى قيمة ((46.48 عند التركيز ML(0.5x10 - 3) مقارنة مع قيمته (9.28) عند نفس التركيز للصبغة القابلة قبل الخلط للانموذج(الاكردين اورنج + البوب بوب)و كانت شدة طيف الانبعاث (الفلورة) عند اعلى قيمة (39.85) بالتركيز (0.5x10 - 3) Ml مقارنة مع قيمتها للصبغة القابلة قبل الخلط والتي كانت (9.15) لنفس التركيز.وقد حصلت ظاهرة الانتي ستوكس (anti - Stokes ) في انموذج (الاكردين + البوب بوب )مقارنة مع حصول ظاهرة ستوكس (Stokes ) قبل الخلط لكلا الصبغتين.اما في انموذج (الاكريفلافين + البوب بوب) فقد حصلت ظاهرة الستوكس (Stokes)وهذا مطابق مع حصول الظاهرة للصبغتين على انفراد.وبعد تحضير انموذجي الخلط لاحظنا تغير جميع الخواص البصرية الخطية (معاملي الامتصاص والانكسار الخطيين, زمن عمر مستوي الفلورة , النتاج الكمي ) عما كانت عليه قبل الخلط للصبغات على انفراد. | In this research was the study of the phenomenon of fluorescence energy transfer between some laser dyes. To get the energy transition process must equal absorption energy spectrum of the first dye (accepter molecule) with florescence energy spectrum for the second dye (donor molecule). Two models have been prepared in this study , the first of the accepter dye (acridine Orange ) with the donor dye (popop), and was second between the accepter dye (acriflavin) with the donor dye (popop) . When measuring the absorption spectrum and the fluorescence spectrum of accepter dyes and donor dye check is considerable overlap between them and this confirms the check model (accepter + donor ). Before starting mixing was studies absorption and fluorescence spectra as well as optical linear properties for all dyes used individually at different concentrations (0.5 x 10 - 3 ,0.5 x 10 - 4 ,1 x 10 - 5 ,1 x 10 - 6)Ml . The results showed change the wavelength of all dyes with change of dye solution concentration .Blue shift has happened with decreasing concentration and decreases both linear absorption and refraction coefficients with decreasing concentration. The study recorded a decrease in quantum yield and increase the lifetime of the energy level of fluorescence with an increased concentration. After preparation of samples (accepter + donor ) to (acridin Ornge and popop ) and concentration mentioned. we have noticed an increase intensity of emission spectrum (fluorescence spectrum), where the highest value (46.48) at the concentration (0.5 x 10 - 3) compared with the value (9.28) at the concentration before mixing. And got the same result after preparation of samples (accepter + donor ) to ( acriflavine and popop ) and concentration mentioned, we have noticed an increase intensity of emission spectrum ( fluorescence spectrum ), where the highest value ( 39.85 ) at the concentration (0.5 x 10 - 3 ) compared with the value (9.15 ) at the same concentration before mixing. It has got anti - Stokes phenomenon in the samples of (acridine Orange and popop ) compared to got stokes phenomenon for two dyes before mixing. In the samples of (acriflavin and popop), Stokes phenomenon has got , this is identical to the one who happened to two dyes before mixing.We note change all the linear optical properties (absorption coefficient , refraction coefficient, quantum yield, lifetime of the energy level of fluorescence) of all samples (accepter + donor) prepared compared to what it was before mixing

دراسة شكل توزيع الشدة لحزمة الليزر بعد انتشارها خلال اوساط مختلفة == A Study Of Laser Beam Profile after Propagation Through Different Media

اسم المؤلف: صفا عبد الكريم رحيم
اسم المشرف: وجيهة عبد الدائم
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بابل
الصفحات الاولى:
المستخلص: تم في هذه البحث دراسة خواص حزمة الليزر لمنظومات ليزرية مختلفة وبظروف مختلفة عمليا ونظريا، وتم ذلك باستخدام منظومة بصرية احتوت على ليزر الهليوم نيون ذو الطول الموجي (632.8nm) والقدرة (1.04mw) وليزر شبه موصل ذو الطول الموجي ( 650nm) والقدرة ( 4.64mw) وليزر حالة الصلبة ذو الطول الموجي (422nm) والقدرة (14.64).وتم الحصول على القياسات باستخدام (CCD CAMERA) نوع (BEAMAGE - CCD12 / Genetic) وكاشف سيليكوني نوع (Silicon PIN) وباستجابة سريعة A/W) 0.41 - 0.7).وقد اظهرت الدراسة ان بقعة الحزمة دائرية منتظمة نسبيا وشكل توزيع الشدة للحزمة توزيعا كاوسيا لليزر الهليوم نيون في الهواء. فيما تغيرت الشدة %( 97.4,97.1,97.1,89.) باختلاف المسافات cm( 10,20,30,40 ) على التوالي وقلت الشدة بزيادة المسافة.فيما اختلفت البقعة عن شكلها الدائري عند استخدام الماء النقي والمالح والمضطرب والملون بصبغة وظهر اختلاف قليل في شكل التوزيع للشدة عن التوزيع الكاوسي وكان التغير اكبر مع الماء المالح والمضطرب والملون بصبغة (GRL)0اما عند استخدام ليزر اشباه الموصلات (650nm, 4.64 mw) تغيرت بقعة الحزمة الى الشكل البيضوي تقريبا، واختلف شكل توزيع الشدة للحزمة عن التوزيع الكاوسي في الهواء. فيما كان تغير الشدة غير منتظم مع اختلاف المسافة. فيما اختلفت البقعة عن شكلها البيضوي عند استخدام الماء النقي والمالح وظهر اختلاف قليل في شكل التوزيع للشدة عن التوزيع الكاوسي وكان التغير اكبر مع الماء المالح والمضطرب والمخلوط بصبغة0 وعند استخدام منظومة ليزر الحالة الصلبة بطول موجي قصير (422nm) وقدرة (14.64mw) فقد حصل تغير ملحوظ في شكل البقعة وكذلك شكل توزيع الشدة، حيث وجد تعريض كبير في شكل توزيع الشدة في الهواء. اما في الاوساط المادية الاخرى المستخدمة فقد حصل تغير كبير شكل البقعة(تشويه) وفي شكل توزيع الشدة عند تغير ظروف الوسط المادي واعلى حالة للتغير كانت عند استخدام الماء النقي والمالح المضطرب لليزر 422nm ، ومن نتائج الشدة تبين تغير غير منتظم في قيمها للاوساط والمسافات المختلفة. نظريا تم ادخال النتائج العملية الخاصة بقياس توزيع الشدة على المحورين (x,y) بتغيير محور z في برنامج حاسوبي خاص (GnoPlot) للحصول على شكل توزيع الشدة للحزمة الليزية في الهواء واظهرت نمطا كاوسيا للهليوم نيون فيما اظهرت اشكال اخرى لتوزيع الشدة تبعا لنوع الليزر وللوسط المادي المار خلاله. وسجلت النتائج النظرية تطابقا نسبيا مع النتائج العملية لجميع الحالات. | In this search of the properties were study of the beam laser to different laser system and different condition , theatrically and experimentally. By using optical system consist of the Helium neon (He - Ne) laser( =632.8nm,p=1.04mw) and semi - conductor (=650nm,p=4.64mw ) and semi - conductor(=422nm,p=14.64mw). . . The parameters beam laser (spot, shape , intensity ) were study and also study the attenuation and turbulence .for the laser mentioned above and with following environmental condition. . First : study of the properties of laser beams of the three system in the air at different distance (10,20,30,40)cm. . Second : study of the properties of laser beams of the three system in the pure ,slate (seawater ) water (still , turbulence ) at different distance (10,20,30,4 )cm . Third : study of the properties of laser beams of the three system in GRL dye with construction (10 - 7 ). Measurement were obtained by using a CCD camera and silicon detector type (BEAMAGE - CCD12 / Genetic ) and silicon detector type (silicon PIN) in fast response (0.41 - 0.7A/W). The result has shown that the spot beams relatively regular circuit and the shape of the distribution intensity was Gaussian shape of He - Ne laser in air. . While the peak values changed with different distance (97.4,97.1,97.1,89.3)% , and decrease intensity with increase the distance. While different spot on the circular shape when using pure , slate (turbulence) and color dye and appeared a little difference in the shape of intensity distribution for Gaussian shape intensity and the biggest change was with slate , turbulence , water and color dye (GRL). . it was noticed the intensity wasn’t regular at different distance ,the absorption coefficient value of the three cases was calculated (0.0014,0.0033,0.0033,0.0021,0.0060 )cm - 1 respectively . But when using semi - conductor laser (650nm,4.64mw)the spot beam laser was change to the elliptical shape almost , and different the shape of intensity distribution of the beam for distribution Gossans shape in air , while the change intensity was irregular with different distance , value of absorption coefficient was (0.0022,0.0055,0.0036,0.0028,0.0036 ) . while the spot difference for circular shape when using pure ,slate water and appeared a little difference in intensity distribution shape than Gaussian distribution ,the bigger change with slate turbulence water and color dye , it was noticed the change intensity was not regular at different distance . But when using semi - conductor laser system with short wave length (422nm) and power (14.64mw) noticeable change in the shape of spot has got and distribution intensity shape . Where found a large boarding in the shape distribution intensity in air ,but in other maternal medium using , the large change in spot shape has got and intensity distribution shape when change the media conditions, the highest case of the change when using turbulence pure and salt water. From intensity results shows irregular change in value of the different medium and distance ,value of absorption coefficient was (0.0070,0.0013,0.0025,0.0013,0.0013 ) . it was noted that the value of coefficient absorption is the least and in all conditions from other lasers. This shows the possibility use this laser in optical communication special under water. . theoretically, the special experimental results with measure intensity distribution was enter on the axis (x ,y ) by change z axis in special program computer (Gnoplot) to get on shape intensity distribution of the beam laser in air and different distance and showed Gaussin mode for He - Ne , while showed other shape for intensity distribution depending on type of the laser and material medium through passing and different distance . Theory results recorded relatively match with experimental results for all cases

دراسة عملية ونظرية لمستويات الطاقة الالكترونية والتذبذبية لبعض الاوساط الفعالة لليزرات الصبغة == The study of practical and theoretical levels Electronic and vibrational energy to some active media for dye lasers

اسم المؤلف: منى لطيف حمد
اسم المشرف: لازم حسن عبود | جبار حسين ابراهيم
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: بابل
الصفحات الاولى:
المستخلص: This research included the practical and theoretical study, as follows : - The study of the energy levels of molecular vibrational experimentally and theoretically, and in the study process measured vibration modes for solution two dye (Pop - Pop + Chloroform) and (Acridine Orang + ethanol) and the calculation of the intensity of absorption and the wave number of the infrared spectrum Central (MID - IR.) using infrared spectrometer F.T. I.R.As for Theoretically was calculated and the diagnosis of the fundamental vibrational modes of Acridine Orang dye, and calculate their intensity as well as wave numbers using a program (Gaussian 09) from these modes C - H str. , C - H ben. , C - O ben. , C = Cstr. , C= N str …….From above results noticed that there's a mismatch between practical and theoretical results of vibrational modes with a relative difference between the intensities measured practically and theoretically.In the second part it has been studied the electronical energy levels of molecules experimentally and theoretically. The study was conducted using different solvents know the effect of the solvent type and the different concentrations (0.5×10 - 3 , 1×10 - 3, 0.5 ×10 - 4, 1×10 - 4 , 1×10 - 5)Ml to pop - pop dye with Chloroform and toluene solvent, and Acridine Orang dye with ethanol solvent . On the other the absorption , fluorescence spectra , linear optical properties (absorption coefficient, refractive index, life time , Life time and quantum yield of florescence level ).Ranged wavelengths of the absorption spectra for pop - pop solutions between (352 - 337) nm in Chloroform and (343 - 337) nm for first peak and(358 - 355) nm for toluene the second peak. In the Acridine Orang solutions, wavelengths ranged between (490 - 478) nm in ethanol.All these wavelengths with in the transitions in molecular electrical orbits at type (n*).the results were shifted absorption spectrum and emission (fluorescence) spectra peaks to ward shorter wavelengths (blue shift), increase the value of liner absorption coefficients and liner refractive index when increasing at the concentration of the solution.from the results shows that the life time of fluorescence increases quantum yield decreases with increasing concentration of the solution.By using a program (Gaussian view 0. 5) has been drawing the molecular electrical orbits theoretically of Acridine Orang dye, and diagnosed (n ,  , *,  , *) orbits, which recorded a match which was a transitions in at type (n*).Theoretically, using a program (Gaussian 09) were studied energy of the levels (HOMO , LUMO), the energy (8.451 eV) and (0.1306 eV) respectively, as well as energy gap (Eg 8.451 eV) has been calculated

حسابات انموذج القشرة لبعض النويات الغريبة حول القلب المغلق 132Sn == Shell Model Calculations of some Exotic Nuclei around the Core 132Sn

اسم المؤلف: سارة مهدي عبيد الشريفي
اسم المشرف: فـؤاد عطية مجيـد
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الاغشية الرقيقة
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بابل
الصفحات الاولى:
المستخلص: اجريت حسابات انموذج القشرة وبنطاق واسع وبدون تقييد لدراسة مستويات الطاقة ومعدلات الانتقال المختزلة B(E2;0_1^+→├ 2_1^+ )┤ ، B(E2;2_1^+→├ 4_1^+ )┤ وطاقات الربط للنظائر134,136Sn ، 134,136Te ، 136,138Xe ، 138Ba . لقد اجريت الحسابات باستخدام برنامج انموذج القشره الحديث NushellX@MSU عن طريق توظيف التفاعلات المؤثرةjj56pna, jj56pnb, kh5082, cw5082, jj56cdb, khhe . لقد اجريت الحسابات قرب القلب المغلق 132Sn في فضاء النموذج jj56pn وبدون اي قيد مفروض على نيوكليونات التكافؤ خارج القلب المغلق.قورنت حسابات مستويات الطاقة ومعدلات الانتقال المختزله وطاقات الربط مع البيانات العملية المتوفرة حديثا. تم الحصول على نتائج ملائمة ومرضيه وذلك عن طريق مقارنه القيمة المطلقة للفرق بين المستويات 2_1^+ و4_+^1 النظرية والعملية لجميع النظائر قيد الدراسة. تم الحصول على طاقة الربط النووية بشكل ممتاز عن طريق حسابات انموذج القشرة الحالية. من خلال المقارنه بين الحسابات النظرية لمستويات الطاقة المتهيجه واحتمالية الانتقال الكهربائي المختزلة B(E2) مع البيانات العلمية، توصلنا الى استنتاج انه لا يوجد تفاعل مؤثر شامل في هذه المنطقة ونحتاج الى الكثير من البحوث لدراسة الخصائص النووية الاخرى التي يمكن ان تساعدنا في فهم افضل للنويات التي تقع بجوار 132Sn. | Unrestricted large - scale shell model calculations have been performed to study the energy levels, reduced transition probabilities B(E2; 0+ → 2+), B(E2; 2+ → 4+) and binding energies for 1 1 1 1134,136Sn, 134,136Te, 136,138Xe and 138Ba isotopes. The calculations have been performed using the recent shell model code NushellX@MSU byemploying j j56pna, j j56pnb, kh5082, cw5082, j j56cdb and khhe residual effective interactions. The calculations have been performed by taken the core at 132Sn in j j56pn model space without any restrictions imposed on the valence nucleons outside the core.The calculations of excitation energy levels, reduced transition probabilities and binding energies, were compared with the recent available experimental data. A satisfactory results were obtained by comparing the absolute difference between theoretical and experimental 2+ as well as 4+ states for all selected isotopes. The experimental binding energy is very well reproduced by the current shell model calculations. From the comparison between our theoretical calculationsfor excitation spectra and reduced electric transition probabilities B(E2) withthe corresponding experimental data, it is concluded that, there is no universal effective interaction in this mass region and more investigation needed to study other nuclear structure properties that might help us to better understand the nuclei lies in the vicinity of 132Sn core.

الخصائص التركيبية والطوبوغرافية والبصرية لاغشية (CdS : Li,Al) المحضرة بطريقه المحلول الغروي == Structural, Morphological and Optical Properties of CdS : Li,Al Films Prepared by Sol - Gel Method

اسم المؤلف: براق كريم كاظم الحسناوي
اسم المشرف: فؤاد شاكر هاشم الجبوري
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الاغشية الرقيقة
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بابل
الصفحات الاولى:
المستخلص: في هذا العمل, تم تحضير اغشية رقيقة من كبريتيد الكادميوم (CdS) النقية والمشوبة بالليثيوم والالمنيوم بنسب موليه مختلفة (05.0, 1 .0 و15.0٪). بتقنيه الطلاء الدوار بالمحلول الغروي, رسبت على قواعد من الزجاج بدرجة حرارة الغرفة K300 بسرعه دوران 1000 دوره بالدقيقة الواحدة وزمن دوران 10ثواني وحرارة تلدين 623 كلفن ولمدة 150 دقيقه.طيف حيود الاشعة السينية اظهر ان جميع الاغشية المرسبة كانت متعددة التبلور وذات تركيب سداسي والاتجاه مفضل على طول المستوي (002) ماعدا الاغشية المشوبة بنسب موليه 0.1 و0.15 من الليثيوم غيرت الاتجاه المفضل الى المستوي (100) ومعدل الحجم الحبيبي لاغشية CdS) ) تساوي 8.666 نانومتر ومع زياده نسب التشويب فان معدل الحجم الحبيبي يزداد حيث وجد بمدى (9.341الى 11.112 نانومتر ل(CdS : Li ) و(9.331 الى 10)نانومتر ل ((CdS : Al. تم دراسة طبوغرافية السطح باستخدام مجهر القوى الذرية (AFM) ان مربع معدل الجذر والخشونة يزداد بزيادة التشويب,البيانات من صور AFM)) تظهر الجسيمات محددة بشكل جيد كمعالم مع مورفولوجيا الحبيبية ويشير الى وجود حبيبات بلورية صغيرة. الدراسة البصرية لاغشية الرقيقة كبريتيد الكادميوم (CdS) النقية والمشوبة من الليثيوم Li) ) والالمنيوم(Al) اظهرت قيمة جيده للنفاذية التي تتجاوز (87.0 - 91.8%) ل (CdS ) وبين منطقة الضوء المرئي (اطول من 500) ومنطقة تحت الحمراء ولكنها تتناقص الى حدود89.3%) , 77.4) و(85 - 88%) مع نسب التشويب العالية من الليثيوم والالمنيوم (0.15مول %) . الامتصاصية العالية في منطقة الموجات فوق البنفسجية تجعلها مناسبة اكثر للتطبيقات كنوافذ للخلايا الشمسية. والانتقالات الالكترونية مباشرة مسموحة وفجوة الطاقة البصرية تساوي 3.08 eV للغشاء النقي (CdS) وتساوي 2.89 eV) الى 2.97eV ) CdS : Li وCdS : Al (2.927eV to 3.025 eV)) مما يدل على ان قيم فجوة الطاقة تتناقص باضافة نسب مولية مختلفة لكل من الليثيوم والالمنيوم السلوك العام للثوابت البصرية مثل معامل الامتصاص, معامل الانكسار ، معامل الخمود ، وثابت العزل الحقيقي والخيالي وفقدان العزل والتوصيلية البصرية تزداد مع زيادة نسب التشويب المولية الليثيوم والالمنيوم لجميع النماذج في مناطق الضوء المرئي وتحت الحمراء. | In this work, pure cadmium sulfide(CdS) and Li, Al - doped CdS with different percentages of (0.05, 0.1, and 0.15 mol%) thin films were prepared by using sol - gel spin coating technique, deposited on glass substrates at room temperature (RT) (300K) with the spin speed and spin time of 1000 rpm and 10 seconds and annealed at temperature 623 K for 150 min. The XRD pattern revealed that all deposited films are found to be polycrystalline with a hexagonal wurtzite structure with a preferred orientation along the (002) plane, excepted the doping films by 0.1, and 0.15 mol% Li was led to change the preferable orientation to (100) plane. The average crystallite size for pure CdS films is equal to 8.666 nm. As the doping percentage increases, the crystallite size increase where is found to lie in the range of 9.341 nm to 11.112 nm for CdS : Li, and 9.331 nm to 10 nm for CdS : Al. The surface morphology of thin films is studied by using atomic force microscope (AFM). The roughness and root mean square values are increasing with the increasing of Li, Al doping concentration and the data from AFM images show well defined particle like features with granular morphology and indicates the presence of small crystalline grains. The optical study of pure cadmium sulfide(CdS) and Li, Al - doped CdS showed good transmittance value, that exceeds (87.0 - 91.8%) for CdS in VIS (longer than 500 nm) and NIR region, but it decreases to the range (77.4 - 89.3%), and (85 - 88%) , with a high doping ratio of lithium and aluminum (0.15 mol %), respectively. The high absorbance in UV region makes it more suitable for applications as a window in solar cell. The electronic transitions was directly allowed and the optical energy gap (Egopt ) were equal to( 3.08 eV) for pure CdS and( 2.89 eV to 2.97eV) for CdS : Li, and (2.927eV to 3.025 eV) for CdS : Al, which indicates that the optical energy gap values decrease with additive both Li and Al mole percent. The general behavior of the optical constants such as absorption coefficient, refractive index, extinction coefficient, real and imaginary parts of dielectric constant, dielectric loss angle, and optical conductivity increases with the increasing of doped CdS by Li and Al mol % in all samples in the VIS and NIR regions

تاثير امتزاز الغاز على التركيب الالكتروني لشرائط نانوية هجينة من السلسين - الجرافين باستعمال نظرية الكثافة الدالية == Effect of Gas Adsorption on the Electronic Structure of Silicene/Graphene hybrid Nanoribbons using Density Functional Theory

اسم المؤلف: علي صبحي جابر الخواجة
اسم المشرف: حمد رحمن جبر
الموضوع العام: علوم الفيزياء
السنة: 2016
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بابل
الصفحات الاولى:
المستخلص: تم استقصاء امتزاز مجموعة جزيئات غاز شائعة وهي CO وCO2 وNH3 وNO NO2 وSO2 على اشرطة نانوية مؤلفة من سلسين|جرافين ((SiGNRs باستعمال نظرية الكثافة الوظيفيةdensity functional theory (DFT) وبتقريب (PBE) Perdew, Burke, and Ernzerhof مع مجموعة الدوال الاساس 6 - 31G. اظهرت النتائج ان امتزاز جميع الغازات CO وCO2 وNH3 وNO وNO2 على الاشرطة النانوية للسلسين|جرافين هو امتزاز كيمائي قوي مع طاقات امتزاز اكبر من1eV ، ونتيجة للتفاعل القوي لهذه الغازات على الاشرطة النانوية للسلسين|جرافين فان هذه الاشرطة النانوية يمكن ان تستعمل كمحفز او منشط ، وبالتالي امكانية اقتراحها كمحفز خالية من المعادن، باستثناء الامتزازات الاتية : CO2 على الاشرطة النانوية للسلسين|جرافين المشابه للكرسي عند الموقع T1، وامتزاز NH3 وNO2 على SiGNR المشابه للكرسي عند الموقع T2، وامتزاز NO وNH3 على SiGNR ذو النوع المتعرج عند الموقع T2، وامتزاز NO2 على SiGNR ذو النوع المتعرج عند الموقع T1 وجميع امتزازات SO2 على SiGNRs فانها امتزازات فيزيائية ضعيفة وبطاقات امتزاز تتراوح ما بين0.045) eV الى(0.84 ، وهذا يدل على ان SiGNR يمكن ان يكون كمتحسس جيد لـ (,CO CO2، NH3, NO2 وSO2) عند المواقع المشار اليها. علاوة على ذلك، فان فجوة الطاقة للاشرطة النانوية للسلسين|جرافين عند امتزاز الغازات CO2 وCOو NH3 وNOو NO2 وSO2 تكون مفتوحة وبطرق مختلفة. بشكل عام، فان فجوة الطاقة لـSiGNR المشابه للكرسي اكبر من تلك التي لـ SiGNR ذو النوع المتعرج. وقد وجدنا ان SiGNR المشابه للكرسي والذي يمتز جزيئات الغاز لـ CO وCO2 وNH3 وSO2 عند الموقعT1 تكون قيمة جهد التاين والالفة الالكترونية له صغيرة بالمقارنة مع اشرطة السلسين|جرافين الاخرى، وهذا يدل على ان هذه الانظمة لديها القدرة على التبرع بالكترون، اي يحتاج الى طاقة صغيرة لازالة الكترون لتصبح ايونات موجبة.توضح النتائج ايضا على ان القيمة الاكبر لـ EHOMOلامتزاز NO وNO2 للنوع المتعرج لـ SiGNR عند الموقع T1 هي eV5.635 - وeV5.541 - على التوالي، وهذه القيم تظهر ميل الجزيئة للتبرع بالالكترونيات والقيمة الاصغر قيمة لـ ELUMO للنوع المتعرج لـ SiGNR عند الموقعT1 هي eV5.344 - و5.315 eV - ، وهذه القيم تظهر ميل الجزيئة الى تقبل الالكترونات | The adsorption of common gas molecules (CO, CO2, NH3, NO, NO2 and SO2) on silicene/graphene nanoribbons (SiGNRs) is investigated using density functional theory (DFT) with Perdew, Burke, and Ernzerhof (PBE) /6 - 31G basis set. The results show that all the adsorption of (CO, CO2, NH3, NO and NO2) on SiGNR is a strong chemisorption with adsorption energies being larger than 1eV, due to the strong interaction of (CO, CO2, NH3, NO and NO2) on SiGNR which could catalyse or activate, suggesting the possibility of SiGNR as a metal - free catalyst. Except the adsorption of CO2 on armchair SiGNR at site T1, NH3 and NO2 on armchair SiGNR at site T2, CO and NH3 on zigzag SiGNR at site T2, NO2 on zigzag SiGNR at site T1 and all adsorbed SO2 on SiGNRs are weak physisorption with Ea ranging from (0.045 to 0.84) eV, indicating that SiGNR could be a good (CO, CO2, NH3 NO2 and SO2) sensor at these sites. Moreover, the energy gap of SiGNR is opened upon adsorption of (CO, CO2, NH3, NO, NO2 and SO2) in various ways. In general, the energy gap for armchair SiGNR is larger than those of zigzag SiGNR. We found that the armchair SiGNR with CO, CO2, NH3 and SO2 gas molecule adsorption at site T1 has small value of ionization potential and electron affinity compared with other SiGNRs, this indicates that these systems have the ability to donate an electron; it needs a small energy to remove an electron to become cation. Our results indicate that larger values of EHOMO for adsorption NO and NO2 zigzag SiGNR at site T1 is ( - 5.635 and5.541 - ) eV, show that a propensity of the molecule to donate electrons and smaller value ELUMO for zigzag SiGNR at site T1 is ( - 5.344and - 5.315) eV, these values show that a propensity of the molecule to accepter electrons

دراسة تاثير قدرة وطول موجة الليزر على خواص محاليل الكادميوم والحديد النانوي المحضرة بطريقة القشط الليزري == Study effect the power and wavelength of laser on the properties of Cadmium and Iron nanosolutions prepared by ablation laser method

اسم المؤلف: ليلى حاكم علك الطفيلي
اسم المشرف: غالب عبد الوهاب الدهش
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: بابل
الصفحات الاولى:
المستخلص: في هذه الرسالة تم استخدام طريقة سهلة وسريعة لتحضير جسيمات نانوية باستخدام تقنية الاستئصال بالليزر النبضي في سائل (LP - PLA) للهدف (الحديد النقي , الكادميوم النقي) المغمور في (2mL) من محلول (الماء المقطر, الايثانول ,SDS) , عند استخدام طاقات واطوال موجية مختلفة (1064nm,532nm,355nm) لليزر Nd : YAG . ان عملية الاستئصال تمت في محاليل مختلفة ( الماء المقطر والايثانول وكذلك في محلول (SDS) وبتراكيز مختلفة) .درست الخواص التركيبية والبصرية للنماذج المحضرة وفحصها باستخدام جهاز المجهر الالكتروني الماسح ( SEM ) , والمجهر الالكتروني النافذ ( TEM ) ومطياف الاشعة المرئية - فوق البنفسجية (UV - Vis).ان الاستئصال الليزري للحديد انتج جسيمات نانوية كروية ذات حجم حبيبي اقل من (10nm) في الماء المقطر , كما يلاحظ حدوث انحراف نحو الاطوال الموجية القصيرة (blue shift) عند استخدام الطول الموجي (532nm) وهذا يدل على نسبة التنوي اعلى من بقية الاطوال الموجية وهذا يؤدي الى نمو حبيبات اصغر داخل البلازما . لوحظ حدوث (blue shift) للجسيمات النانوية مع زيادة الطاقة عند الاستئصال بطول الموجي (1064nm) في محلول الايثانول. اما في محلول SDS اظهر افضل كفاءة عند التركيز (0.005M) عند الاستئصال بطول الموجي (1064nm) واستخدام طاقة قليلة (100mJ) ادى الى انتاج جسيمات نانوية ذات حجم صغير وتركيز قليل مما يقلل تصادمها مع بعضها وهذا يؤدي الى تقليل فرص التحام (coalescences).ان الاستئصال الليزري للكادميوم اظهر افضل كفاءة واكثر استقرارا في محلول الايثانول , حيث اظهرت صور TEM الجسيمات النانوية التي اعدت عند الطول الموجي (355nm) اكثر تجانسا من NPs التي اعدت عند طول موجي (1064nm) . صور SEMومخططات EDX للجسيمات النانوية الغروية للحديد والكادميوم الناتجة من الاستئصال عند طول موجي (1064nm) في محلول الايثانول التي اظهرت نقاوة المحاليل النانوية الناتجة . تم تحضير محلول نانوي غروي Core - Shell لنظام Cd - Fe بواسطة استخدام طول موجي (1064) نانومتر في الايثانول ,حيث اظهرت صور TEM تشكيل Core - Shell بشكل واضح. وكذلك اظهرت صور TEM للجسيمات النانوية الغروية , تكوين حبيبات نانوي بحجم اقل من (10) نانومتر . | In this research a quick and easy method has been used for preparing nanoparticles using (PL - PLA) of pure targets (pure iron ,pure cadmium ) submerged in (2mL) of solution ,by using different wavelengths and energy of laser Nd : YAG. Ablation processes that had been done in various solvents(distilled water and ethanol ,as well as in different concentrations and SDS solution. Structural and optical properties were examined used a scanning electron Microscope (SEM) and transmission electron microscope(TEM) and UV - Vis. Spectrometer. Laser ablation of iron produced multiple nanoparticles spherical nucleus of a grain size less than (10nm) in distilled water, also notes a deviation occurs towards the short wavelengths (blue shift) when using the wavelength (532nm). This shows that the proportion of nucleation is higher than the other wavelengths and that leads to the growth of smaller particles within the plasma. Well happened (blue shift) of nanoparticles with increased energy at wavelength (1064nm) in ethanol solution ,but in the SDS solution showed the best efficiency when the concentration (0.005M) at wavelength (1064nm) .When using a small power lead to production small size and concentration of nanoparticles that reduces collisions with each other and this leads to reduced coalescences. Laser ablation for cadmium showed better efficiency and more stable in ethanol solution, which marked the TEM images of nanoparticles prepared when the wavelength (355nm) more homogeneous than NPs prepared with wavelength (1064nm). Images of SEM and EDX schemes of nanoparticles iron and cadmium colloidal resulting from ablation at the (1064nm) in wavelength ethanol solution show that the purity of the solutions resulting nanoparticleThe nanocolloide solution of Core - Shell system (Cd - Fe) was prepared by using a wavelength (1064) nm in ethanol,where the TEM pictures showed the formation of Core - Shell clearly. As well as the picture showed (TEM) of colloidal nanoparticles with nanoscale particles size less than (10)nm .

تحضير ودراسة خواص مادة اوكسيد الرصاص النانوية == Preparation and Study of ( PbO ) Nanomaterials Properties

اسم المؤلف: علي فاضل مرموص عبود
اسم المشرف: عبد العزيز عبيد موسى العكيلي
الموضوع العام: علوم الفيزياء
السنة: 2016
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بابل
الصفحات الاولى:
المستخلص: في هذا العمل تم تحضير اغشية رقيقة من اوكسيد الرصاص (PbO) باستخدام تقنية الرش الكيميائي الحراري وهي طريقة سهلة ومناسبة للترسيب على مساحات كبيرة. استخدم كلوريد الرصاص المائي PbCl2.2H2O كمصدر للحصول على جسيمات الرصاص. تم انماء مزيج اغشية (PbO) بدرجات حرارة مختلفة °C (200, 250 ,300 , 350, 400 و450) على قواعد زجاجية وقد استخدم غاز النتروجين بضغط (4.5 بار) كغاز حامل . تم فحص التركيب البلوري للاغشية بطريقة حيود الاشعة السينية ( XRD) اوضحت النتائج ان جميع الاغشية المحضرة كانت متعددة التبلور واظهرت النتائج بان الاغشية المرسبة بـ (200 °C ) , ( (250 °C ,( 300°C) , و( 350 °C )كانت بقمة (002) بينما الاغشية المرسبة بـ (400°C و450 °C ) كانت تحمل القمة (112) القمم. في حين اظهرت النتائج وجود تحول من النظام الرباعي القائم الى النظام المعيني القائم فوق (350 °C) . درست طبوغرافية السطح للاغشية المحضرة باستخدام مجهر القوى الذرية (AFM) والمجهر الالكتروني الماسح) SEM) ومبدد الطاقة للاشعة السينية (EDX) . الحجم الحبيبي لجسيمات (PbO) النانوية وجد انه يقل بزيادة درجة حرارة السطح . ام فحص (EDX) اظهر احتواء الاغشية المحظرة على عناصرPb ) وO ) كما هو متوقع ، مشيرا الى تشكيل اغشية(PbO) نقية. الخصائص البصرية للاغشية المحضرة بسمك (177nm) تم دراستها باستخدام قياسات النفاذية البصرية في المنطقة الطيفية (250 - 760 nm) . نتائج النفاذية كانت اكبر من 80% . فجوة الطاقة المباشرة للــ (PbO) كانت ضمن مدى 1.61 - 2.80) eV) ، والتي تتزايد مع زيادة درجة حرارة السطح . الثوابت البصرية كمعامل الانكسار ومعامل الخمود وثوابت العزل تم حسابها لجميع الاغشية المحضرة . الخصائص الكهربائية مثل التوصيلية الكهربائية المستمرة وتاثير هول تم دراستها ايضا . وكانت نتائجها تشير الى ان الاغشية من النوع السالب ( n - type ) وتمتلك طاقتي تنشيط ( Ea1 , وEa2 )، وقد وجد ان التوصيلية الكهربائية المستمرة تزداد مع زيادة درجة حرارة سطح القاعدة. | In this work, thin films of lead oxide (PbO) were prepared by using a homemade chemical spray pyrolysis (CSP) technique, which is a simple, inexpensive and suitable technique for large deposition area. The lead chloride PbCl2.2H2O is used as a source of lead particles. (PbO) thin films with different substrate temperatures (200, 250, 300, 350, 400, and 450) ̊C have been grown on clean glass substrate with the nitrogen carrier gas (4.5 bar).The crystal structures were examined by X - ray diffraction (XRD) analysis. The result shows that all the prepared films are polycrystalline structure. It indicates that the films coated at 200°C, 250°C, 300°C, and 350°C are (002) oriented, while the films deposited at 400 °C and 450 °C are (112) oriented. Above 350 °C, the pure tetragonal nature deteriorated and the peaks corresponding to orthorhombic phase are observed. The surface morphology of the deposits films have been studied by using atomic force microscopy (AFM), scanning electron microscopy (SEM) and energy dispersive X - ray (EDX). The grain size of the (PbO) nanocrystalline observed at the surface decreases with increasing of substrate temperature, leads to increase in the surface roughness. (EDX) shows that all the films contain the elements (Pb and O) as expected, indicating formation of the (PbO) films with high purity. The optical properties of the films, which are prepared with thickness of (177 nm), have been determined by using the optical transmittance measurements in the spectral region from (250 - 750) nm. Transmittance results is upper than 80%. Direct energy gap for (PbO) is in the range (1.61 - 2.80)eV, it increases with increasing substrate temperature. The optical constants such as refractive index, extinction coefficient and dielectric constant have been calculated for all preparing films. The electrical properties include D.C conductivity and Hall effect are studied. The results show that the prepared films are n - type, and have two activation energies (Ea1 and Ea2). It is found that the electrical D.C conductivity increased with the increase of substrate temperature.
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