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تحضير ودراسة الخصائص البصرية اللاخطية لمواد بلورية سائلة نيماتية مطعمة بجسيمات نانوية == Preparation and Study Non - linear Optical Properties of Nematic Liquid Crystal Materials Doped by Nanoparticles

Author name: بان علي ناصر غالب
Supervisor name: عبد العزيز عبيد موسى العكيلي | ياسين حسين كاظم
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Babylon - College Of Science - Physics Department
Language: English
University location: Babylon
First pages:
Abstract: The present research include preparation the nematic liquid crystal materials doped with nano materials and studies the structural ,linear and nonlinear optical properties, for using it in field of nonlinear optics. Many properties of liquid crystal can be improved and enhanced by doping with nanoparticles materials, which are favorable for practical applications.Nematic liquid crystals (NLCs) (pure and doped) good materials for field of nonlinear optics (NLO) and its applications because of their large non - response nonlinearity and their extended spectral transparency.In this work, preparation of two compounds (ligands) of liquid crystal Schiff's bases derived from benzidine and hydrazine (Di - Cinnamylidene Benzidine) (B1) , (Bis - 4 - Methoxy - Benzyldene - Hydrazine) (B2) , and their complexes with bivalent ions (Cu, Ni, and Zn), take samples (M1B1,M2B1,M3B1, M1B2,M2B2 and M3B2) nanoparticles materials respectively, were carried out. As well as thin films of solutions of two materials (Di - Cinnamylidene Benzidine) and (Bis - 4 - Methoxy - Benzyldene - Hydrazine) and their complexes have been deposited on glass substrates, the samples prepared from solutions via spin - coating method at (10 - 3 M).The ligands and their complexes have been characterized by using FT - IR spectra and polarized optical microscopy (POM) to study liquid crystalline behavior, which has shown that the compounds have liquid crystalline properties belong to enantiotropic nematic phase (bi case media).The crystal structure has been studied for all prepared samples by using X - Ray diffractometer (XRD) ,and it has shown that ligands have polycrystalline structure. The complexes (M1B1,M2B1,M3B1 and M2B1) have monoclinic structure .The complex (M1B2 ) have orthorhombic structure, and the complex (M3B2) have amorphous structure.Atomic force microscopy (AFM) measurements for all samples show that the grain size ranging from (70 - 89) nm.The linear optical properties for all prepared samples have been studied, a study of UV - VIS spectra for different concentrations for each material dissolved in absolute ethanol solvent (9×10 - 5,8×10 - 5,7×10 - 5, 6×10 - 5, 5×10 - 5 and 4×10 - 5) M ,then study of absorption and transmission spectra for all prepared thin films at 10 - 3 M. The results showed when the concentrations increased the absorbance also increased for the same wavelength. The opposite relationship was observed for transmittance.The nonlinear tests calculated used (Z - Scan) technique in two cases (Close aperture) and (Open aperture) for obtain nonlinear refractive index coefficient (n2) and nonlinear absorption coefficient (β).The measurements performed using diode pump solid state laser operating at (473 nm) wavelength. The results showed an increase both of the nonlinear refractive index coefficient and nonlinear absorption coefficient, when increasing concentrations for all samples of liquid crystal material(solutions and thin films).The nonlinear refractive index increased linearly with the nonlinear phase shift .The thin films possess large linear and nonlinear optical properties as compared with liquid crystal as solution.The result imply that thin films of pure nematic liquid crystal and its complexes can be used as a potential medium for various optoelectronic applications including that in optical power limiting. The result show that the optical power limiting threshold is inversely proportional to the concentration of solution for all prepared samples.

تصنيع حراريات من البوكسايت العراقي == Refractories Manufacturing from Iraqi Bauxite

Author name: ایناس محي هادي
Supervisor name: محاسن فاضل هادي الكاظمي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Mustansiriyah University - College Of Science
Language: Arabic
University location: Baghdad
First pages:
Abstract: Iraqi raw Bauxite was fired at (1400) ̊C in order to produce calcined Bauxite. Chemical analysis and X - Ray Diffraction were carried out on the Iraqi Bauxite and calcined Bauxite to assess their ability for refractories production.The refractory mixture prepared from calcined Bauxite and raw Kaolin as a binder. The Kaolin was added in ratios of (10%, 20% and 30%). From the results of physical properties it was found that the mixture which has (10%) kaolin is the most suitable one for refractory production. Micro and Nano Zirconia and raw Zircon were added in ratios of (5%,10%,15% and 20%) in order to improve Iraqi Bauxite characteristics to be suitable for refractories production which are used in glass and metals industries.The samples were formed by semi - dry pressing with different load with the addition of potassium silicate in ratio of (10%) as a binder. The samples were formed with dimensions for (height × diameter) as : (50×25)mm2, (50×50)mm2, (1×50)mm2, (1×25)mm2 and (50×10)mm2. The samples were dried at room temperature for (24)hr, after that dried by electrical dryer at (110) ̊C for (8)hr. The refractories of (Bauxite - Zirconia) fired at (1400) ̊C and refractories of (Bauxite - Zircon) at (1500)̊C by a firing program with a soaking time for (2)hr.The test which were carried out are : (X - Ray Diffraction and SEM), Physical Testing : (Linear Shrinkage, Apparent Porosity, Water Absorption Ratio and Apparent Density), Mechanical Testing : (Bending Strength, Compressive Strength, Diametrical Strength, Hardness and Surface Roughness), Thermal Testing : (Thermal Conductivity, Specific Heat Capacity, Thermal Expansion Coefficient, Thermal Shock Resistance and Differential Thermal Analysis (DTA). And last test was Chemical Resistance to molten glass.According to (XRD) and (SEM) results the refractories consist mullite phase and glass phase. Refractories of (Bauxite - Nano Zirconia) have the lowest linear shrinkage and highest apparent density then the refractories (Bauxite - Micro Zirconia) and (Bauxite - Zircon).The adding of micro or Nano Zirconia or raw Zircon led to decrease the linear shrinkage and increase apparent density because of the increasing of pure ceramic materials in account of raw ceramic materials. The increasing of apparent density associated with decreasing of apparent porosity and water absorption ratio.The improving of the mechanical properties by adding Zirconia and raw Zircon causes by the high toughness of the additive ceramic materials which is also prove the crack pining mechanism with ceramic particles practically.The increasing of apparent density in susceptible the thermal properties therefore the thermal conductivity, specific heat capacity and thermal expansion coefficient were decreased while thermal shock resistance was increased, according to properties of the additive ceramic materials. The results of the differential thermal analysis shown that the refractories of (Bauxite - Zirconia) have a high thermal stability in the test temperaturerange (25 - 1500)̊C, except some process that return to raw Kaolin, endothermic process were moisture loses and crystalline water loses and exothermic process at (900 - 1000)̊C as mullite phase formed from the reaction between (SiO2) and (Al2O3).The increasing of chemical resistance causes from adding of Zirconia and raw Zircon to the prepared refractories, which led to reduction of wetting ability and the amount of molten glass which adhesive with refractories, on the other hand forbade the chemical reaction between the molten glass and the refractories.

بناء منظومة بلازما حاجز الجهد العازل الانتاج البلازما ودراسة تاثيرها على الدم باستخدام معالجة الصور == Construction of Plasma system of Dielectric Barrier Discharge to study its effects on the Blood using Image processing

Author name: ايمان عبد الستار الحميدي
Supervisor name: حامد حافظ مربط | علياء حسين علي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Baghdad - College Of Science For Girls - Physics Department
Language: Arabic
University location: Baghdad
First pages:
Abstract: In this study, construction the Dielectric Barrier Discharge system (DBD) to produce cold the Plasma was done. The electrical characteristic of the system were studied, the characteristic (Current - Voltages) curve and the effect of (frequency, the distance between electrodes, thickness of dielectric and type of dielectric material) on the value of the discharge current (I) and breakdown voltage have been studied. It was found that each of the discharge current and breakdown voltage increases with increasing gap distance, it was observed that the value of the breakdown voltage in the case of using a Teflon as a dielectric than is higher when using a glass as a dielectric. It is found that the discharge current and breakdown voltage increases with increasing gap space and the thickness of the dielectric material. Also, it's observed that the discharge current increases with increasing frequency of the applied voltage.The total number of prepared sample were (176) all are chosen for men they ages are between (20 - 40) years. The samples have been as follows (healthy, infected with high blood pressure, smokers and diabetes). The samples have been exposured to cold plasma for different periods between (2 - 50) sec. The image for all samples have been captured using Optical microscope. Every image have been studied with image processing programs by using (Mat lab - 2010).To extracted effect of Plasma on the texture of the Blood by using different methods .Histogram for First Class (First - Order Histogram) ,Gray level Co - occurrence matrix (GLCM) (Second - Order Co - occurrencematrix) and masks Law (Law's Mask) a statically features have been calculated for each method to study the effect of Plasma on the Blood texture.It is found that the Cold plasma effect on blood samples each of (smokers, diabetes ) It was Limited and does not appear Significant changein the image texture , and the Cold plasma effect on blood samples each of ( healthy , infected with high blood pressure ) can be seen through the change in the image texture .

دراسة فقدان الطاقة لحزمة ايون الهيدروجين في الحمض النووي والماء == Studying Energy Loss of Hydrogen Ions Beam in DNA and H2O

Author name: اوفى زهير خضير
Supervisor name: خالد عبد الوهاب احمد | رياض خليل احمد
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Mustansiriyah University - College Of Science
Language: English
University location: Baghdad
First pages:
Abstract: The energy delivered by a swift proton beam in materials of interest to hadron therapy (DNA and liquid water) is investigated in the present work. An explicit condensed - state description of the target excitation spectrum based on the dielectric formalism is used to calculate the energy - loss rate of the beam in the irradiated materials.The present work focus on : (i) Calculations of the energy loss, the probability P(E,T) of electronic excitation produced by proton, the average energy <E> transferred to the targets by electronic excitation, Partial Stopping Power, Effective Charge (PSPEC) using the dielectric function (PPA) to describe the excitation spectrum of DNA and H2O. Results show that the protons with energy between 0.05 MeV to 2.5 MeV are very efficient in producing secondary electrons in DNA and H2O, which are able to produce strand breaks and could be very effective for the biological damage of malignant cells.The ionization potential (the so - called I - value) is the most important material quantity in the calculation of the electronic stopping power of energetic ions (>1 MeV u−1) has been evaluated through Bethe’s formula and represents its main source of uncertainty at high energies, I DNA found to be 80.01 and I H2O .(ii) Calculation of shell correction of swift proton has been done by adopting (PPA) dielectric function of DNA and Liquid water targets. As well as calculations of shell correction using HO - GOS, KT - IM and FEG - ELF models, and compared the results come from three models.I(iii) Barkas effect, ( L1) and Bloch correction ( L2) for penetrating proton in DNA and Liquid water have been calculated using (KT, HO and FEG) moels, where the Bethe - Bloch parameters like, Barkas effect, Z 1L 1, Bloch correction, and Shell correction, ⁄ are unknown for DNA and liquid water.Results for protons impacting in the most representative biological targets (such as water or DNA components) show a very good comparison with experimental data. Because of its simplicity and great predictive effectiveness, the method can be immediately extended to any combination of biological target and charged particle of interest in ion beam cancer therapy.The equations of theoretical formulas for interesting physical quantities are programmed in a programs AuFa - H - DNA.for and AuFa - H - H2O.for , [see the flow charts in Appendix A] which contains some subroutines have been written in Fortran - 90 for the numerical calculations.

تصميم متحسسات الياف بصرية للكياسات البيئية == Design of Optical Fiber Sensors for Environmental Measurements

Author name: الهام كاظم اونيس
Supervisor name: محمد صالح مهدي | رياض خليل احمد
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Mustansiriyah University - College Of Science
Language: English
University location: Baghdad
First pages:
Abstract: This study includes two main parts to design and study uniform and apodized fiber Bragg grating. The first part include simulation method by using optigrating 4.2 software in order to get the transmission and reflection spectrum for the FBG, also to give high accurate for analysis the characteristics of the FBG. The work of the software based on coupled mode theory which used the T - Matrix to solve its equations.The simulation study includes designed a uniform and Apodized fiber Bragg grating and studying the effect of increasing grating length on the reflectivity for them. The results show that, increasing grating length for uniform FBG for (L= 05 - - - 40mm) causes to increase the reflectivity to (99.99%) at (L=28mm), but increase in the reflectivity of side lobes which can reduce it by using apodization method in order to reduce the refractive index change towards the ends of the grating. After that, if the length is increased further, it is observed that the maximum reflectivity maintains the same value of (99.99%). The results for the effect of increasing grating length on the bandwidth show that, the value of the bandwidth decreased until achieved (0.01062nm) at grating length 28mm, then stay at this value for longer length.The simulation results for the Apodized FBG show the same behavior as the results of the uniform FBG but without side lobes. The effect of the increasing index modulation on the reflection spectrum was studied for the uniform FBG, from the results we observed that increasing in index modulation causes increasing in the reflectivity, where at the weak grating (1*10 - 4), the reflectivity was low and at the strong grating (4*10 - 4), the reflectivity was high.IIIIn addition, the study includes designing a sensor for a temperature and strain for uniform and apodized FBG. A uniform single temperature sensor is designed at grating length 10mm, the simulation result shows that, the center wavelength shifts with increasing temperature for (25 - 80˚C). The calculated temperature sensitivity for this sensor is (13.8 pm/˚C), Depending on the results we calculate the estimated temperature accuracy which is (± 0.33˚C).Again we design a sensor for the temperature but for array sensor, the results show that, the array sensor will not reflect Bragg wavelength at the same time when the temperature increasing because we take different value of grating period for each fiber in the array sensor. The temperature sensitivity for this sensor is (mean 13.76pm/˚C), and the estimated temperature accuracy is (mean ± 0.73˚C). From the comparison between the single and array sensors, we find that, the single FBG sensor system is more accurate compare to the array sensor, but in term of advantage FBG sensor array system have more advantage compare to the single FBG sensor.The simulation study for apodized FBG temperature sensor gives the same behavior as the uniform single FBG sensor but without side lobes. The results show that, there is no effect of increasing temperature on the bandwidth for the sensor. The strain sensor is designed for the uniform FBG at length 10mm; the results show that, increasing Bragg wavelength for applied strain for (200 - 2600με).The second part for the study includes designing and studying a temperature sensor by using experimental method. The experimental results show that, the reflection and transmission spectrum is at (1553.764nm) and increasing with increasing temperature from 25˚C to 80˚C. The measured temperature sensitivity for the sensor is (13.7 pm/˚C), while the theoretical is (14.2 pm/˚C). The estimated temperature accuracy for the sensor is calculated and is (± 0.32˚C).

تاثير اضافة بولي اثيلين اوكسايد على خصائص بعض البوليمرات في التطبيقات الطبية == Influence of Adding Polyethylene Oxide on Some Polymer Properties for Medical Applications

Author name: احمد شاكر حسين كحيط
Supervisor name: رحيم كعيد كاظم حسين المرشدي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Mustansiriyah University - College Of Science
Language: English
University location: Baghdad
First pages:
Abstract: تضمنت الاطروحة دراسة الخصائص الفيزيائية لبوليمر بولي اثيلين اوكسايد (PEO) باستخدام المذيب ثنائي ميثيل الفورماميد (DMF) باستخدام تراكيز مختلفة (0.1% - 0.8% ) (غم / مل) قبل وبعد اضافة بعض البوليمرات ومن هذه البوليمرات بوليمر بولي اثيلين كلايكول (PEG) والبوليمر بولي مثيل ميثاكريليت ( PMMA) باوزان مختلفة. وتم دراسة الخصائص الريولوجية والبصرية والميكانيكية والكهربائية للنماذج المحضرة السائلة والصلبة حيث : تم قياس الخصائص الريولوجية للعينات مثل (الكثافة واللزوجة القصية)، ثم تم قياس انواع اخرى من اللزوجة مثل اللزوجة النسبية , اللزوجة النوعية , اللزوجة المختزلة , اللزوجة الذاتية ، اما معدل اللزوجة للوزن الجزيئي ونصف القطر الجزيئي الفعال فقد تم حسابها نظريا.وكذلك تم قياس الخصائص البصرية مثل (الامتصاصية ومعامل الانكسار)، ثم من هذه الخصائص تم حساب الخصائص الاخرى مثل (النفاذية ، الانعكاسية ، ومعامل الامتصاص للموجات الكهرومغناطيسية ، وزمن العمر الطبيعي، ومعامل الرقة ، الانعكاس المولاري، الزاوية الحرجة وزاوية بروستر).وايضا تم قياس الخصائص الميكانيكية مثل السرعة للموجات فوق الصوتية والتي تم قياسها على تردد ثابت قيمته (25 كيلو هرتز) اما الخصائص الاخرى تم حسابها نظريا , مثل : معامل الامتصاص للموجات فوق الصوتية , زمن الاسترخاء , سعة الاسترخاء , الانضغاطية , معامل المرونـة الحجمي , الممانعة الصوتية النوعـــية .بالنسبة للخصائص الكهربائية تم قياسها مثل التوصيلة الكهربائية ، وبالتالي حسبت الخصائص الاخرى مثل التوصيلية المولارية ودرجة التفكك . وقد تم قياس كل هذه الخصائص لحالتين قبل وبعد الاضافة في درجة حرارة الغرفة .واظهرت النتائج ان الخصائص السابقة تزداد مع زيادة التركيز باستثناء اللزوجة الذاتية ، النفاذية، الانعكاسية المولارية، الزاوية الحرجة، الانضغاطية، التوصيلة المولارية ودرجة التفكك تتناقص مع زيادة التركيز.تم الحصول على نتائج جديدة لمزيج من البوليمر ولقد استخدمت هذه النتائج في جانب من التطبيقات الطبية ، والتي تضمنت الامتصاصية والنفاذية ، وكذلك من ناحية اخرى ، هناك جانب تم تطبيقه وهو ملاحظة تاثير اضافات البوليمرات على بكتيريا جلد الانسان عند استعمال ثلاثة انواع من البكتريا .حيث لاحظنا عدم تاثر البكتريا عند اضافة كل من بوليمر بولي اثيلين كلايكول وبوليمر بولي مثيل ميثاكريليت والمذيب ثنائي الميثيل فورماميد والمستحضر ( بصورة انفرادية) عند اخذ نسبة (1 : 1) لذلك تستخدم كمواد قابلة لامتصاص الاشعة فوق البنفسجية ولاتستخدم كمواد معقمة اما مايخص بوليمر بولي اثيلين اوكسايد فقد لاحظنا تاثر البكتريا به ولمسافة (15) ملم حيث يمكن استخدامه كمادة قابلة لامتصاص الاشعة فوق البنفسجية وكمادة معقمة ويعتبر هذا احد التطبيقات الطبية الجديدة ، لذلك هناك العديد من التطبيقات التجريبية في التطبيقات الطبية المختلفة التي تم الحصول عليها من هذه الدراسة ، مثال على ذلك : عندما نستعمل بولي اثيلين اوكسايد وكذلك عندما نضيف له بوليمر بولي اثيلين كلايكول والبوليمر بولي ميثاكريليت المثيل حيث تم اضافة المزيج الى ثلاثة انواع من مستحضرات التجميل ، وثلاثة انواع من مرهم المفاصل ونوعين من جل الشعر، وهذه المخاليط ادت الى تحسين الامتصاصية عن طريق زيادة امتصاص (الاشعة فوق البنفسجية ) وجعل الجلد اقل تهيجا.ونلاحظ كذلك ان فحوصات (FT - IR) للاطياف اظهرت عدم وجود تفاعل كيميائي بين ( (PEO الذي ووزنه الجزيئي (300000) ومضافاته حيث استخدمت تقنية اقراص (KBr)) لذلك.العلاقة بين الخصائص التي تمت دراستها والتطبيقات الطبية هو الفائدة من زيادة الامتصاصية وتقليل النفاذية حيث ان الفائدة في الاضافة لهذه المراهم للحد من امتصاص الجسم للاشعة فوق البنفسجية، فضلا عن خصائص الريولوجية التي تؤدي لزيادة اللزوجة للمراهم وبالتالي زيادة الكثافة ومعامل الانعكاس مما يقلل من نفاذية الاشعة (الاشعة فوق البنفسجية) للجسم، بالنسبة للخصائص الميكانيكية والكهربائية لوحظ تحسن كبير في هذه الخصائص التي يمكن استخدامها كبحوث وتطبيقات في المستقبل | The dissertation has included study of some physical properties of polymer polyethylene oxide (PEO) dissolved in Dimethylformamide (DMF) with different concentrations ranged from (0.1% - 0.8%) g./ml before and after adding Polymers such as polyethylene glycol (PEG ) and Poly(methyl methacrylate) (PMMA ) of different weights. The rheological, optical, mechanical, electrical properties for samples at prepared by liquid and solid have been studied and the study show : For rheological properties such as : (density and shear viscosity ),has been measured , then other types of viscosities are measured , such as : relative viscosity , specific viscosity , reduced viscosity , intrinsic viscosity. While for viscosity average molecular weight and effective molecular radius have been theoretically calculated. Also the optical properties had been measured such as ( absorbance and refractive index ), then from these properties were calculated optical parameters and optical constants such as ( transmittance, reflectance, absorption coefficient of electromagnetic waves, natural lifetime, coefficient of fineness, molar reflectance, critical angle and Brewster angle ). Also the mechanical properties of ultrasonic wave velocity at a constant frequency (25 kHz) has been measured and other properties were theoretically calculated such as : absorption coefficient of ultrasonic waves , relaxation time , relaxation amplitude , compressibility, bulk modulus , and specific acoustic impedance for ultrasonic waves. For the electrical properties have been measured such as electrical conductivity and other properties such as (molar conductivity and degree of dissociation) have been calculated after that.The results showed that previous properties have increment with the increase of concentration except reduced viscosity , transmittance , molar reflectance ,critical angle, compressibility, molar conductivity and degree of dissociation are decreasing with increasing of concentration . New results were obtained to a combination of polymer and these results have been utilized in the side of medical applications, which included the absorbance and transmittance, in the other hand, the effect of polymer addition on human skin has been applied according to a note , when using three types of bacteria . Where noticed the bacteria is not affected when adding each of the polymer (polyethylene glycol , Poly(methyl methacrylate)) , solvent Dimethylformamide and mixture when taking the ratio (1 : 1) individually , so it is used to absorb ultraviolet rays and not used as sterile . For polymer polyethylene oxide noticed effect on bacteria for distance (15) mm , where it can be used to absorb ultraviolet rays and sterile , this is one of the new medical applications , so there are many experimental applications in different medical applications obtained from this study, such as : The solutions of (PEO) , (PEO - PEG) and (PEO - PMMA) blends that have been added into three types of cosmetics, three types of ointment of joints and two types of hair gel , these blends enhance them by the increase of (UV) absorbance that makes less skin irritation. The (FT - IR) spectra showed that there was no interaction between (PEO) ( 300000 ) and all additives when it has prepared by (KBr) disks technique. The relationship between the properties that have been studied and medical applications in the usefulness increase absorbance and decreases transmittance that has to take advantage of it in the addendum to the ointments to reduce the body's absorption of (UV) rays , as well as rheological properties led to increase the viscosity of ointments and thereby increase the density and reflection coefficient which reduces the transmittance of (UV) rays to the body , for mechanical and electrical properties noticed a significant improvement in these properties, which can be used research and applications for the future

دراسة بعض خصائص فيرايت الاسبنل المحضر بطريقة السيراميك والسول جيل == Studying some Properties of Spinel Ferrite preparing by Ceramic and Sol - Gel Methods

Author name: اثير ابراهيم عبد علي الخفاجي
Supervisor name: كاظم جواد كاظم الشجيري
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Mustansiriyah University - College Of Science
Language: English
University location: Baghdad
First pages:
Abstract: In this research three series of spinel ferrites samples where prepared which is copper - zinc ferrite with general formula (Cu1 - xZnxFe2O4), magnesium - zinc ferrite with general formula (Mg1 - xZnxFe2O4) and nickel - zinc ferrite with general formula (Ni1 - xZnxFe2O4) at (X) values ranging from 0.0 to 1.0, step of 0.2 where (X) represents the proportion of zinc in ferrite, using two preparation methods which is Conventional ceramic method and Sol - Gel method. Three sintering temperatures have been used which is (1000ºC), (1050ºC) and (1100ºC) to determine the effect of sintering temperature on the final specifications of the samples. (Network analyzer device) has been used to studding the microwaves absorption in the range of (X - band) with a frequency range (8 - 12.5 GHz). Also, X - ray diffraction analysis (XRD) has been used to determine the crystal structure and purity of the prepared samples and to calculate the average grain size and micro strain, The samples were examined using a scanning electron microscope device to evaluate the crystal size and to see distribution style after the sintering process, were Also, the density of the prepared samples were measured to calculate the porosity values.The results showed that the best samples with very high absorbency a long the (X - band) is (Mg0.6Zn0.4Fe2O4) and (Cu0.6Zn0.4Fe2O4) at sintering temperature (1100 ºC). This stability and efficiency observed firstly compared with other researches and literatures. Also the resonance peaks for all three types of spinel ferrite appeared at frequencies (8.6, 9.8, 10.0, 10.2, 11.01.11.2, 11.6, 12.0, 12.2) (GHz). X - ray diffraction results showed that all the prepared samples are a poly - crystalline also showed the occurrence of micro strain on the crystals due to effect of the sintering temperature on the crystals.Comparison between the samples prepared by Sol - Gel method and Conventional ceramic method; the result showed the homogeneity of particle size and particle distribution was the best for first method. Whereas the porosity was small for this method

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

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

تطوير واستخدام منظومه كشف المواد المتفجرة عن بعد == Development and Optimization of Stand off Explosive Material Detection System

Author name: ولدان محمد عواد
Supervisor name: سهى موسى خورشيد الاوسي | كمال حسين لطيف
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: Al-Nahrain University - College Of Science - Physics Department
Language: English
University location: Baghdad
First pages:
Abstract: In order to develop a effected method to reveal the presence of explosive, numerous detection techniques have been studied that are capable of detecting explosives, The current study provides an overview of the present techniques like LIBS which is an atomic spectroscopy, and examined a new technique for detecting called laser induced fluorescence (LIF).LIF essentially measures the optical emission of the excited energetic materials by laser. The use of LIF has led to the discovery of unreported optical characteristics of some compounds that are exclusive to the individual material, like the phase shift and the modulation depth of the fluorescence signals.A high resolution spectrometer is used to record the fluorescence emission wave length for three types of explosive materials, These optical characteristics consist of fluorescence shoulders of the three samples in the wave length between (300 - 370) nm .Using fast rise time photo multiplier and spatial amplification for the fluorescence signal enable us to detect the time domain fluorescence spectrum for three types of explosive materials (AN), (TNT),( C4) and other non - explosive material, this method used Carefully for 8m standoff detection, different type of substrate is examined to simulate the real scan, both the time domain and frequency domain is measured for efficient LIF spectroscopy that give us a total configuration of the tested sample.A library of a total time configuration for different type of material s spectrum enables us to develop a algorithms to distinguish between expl osive and non - explosive material. Used to develop a recognition program to achieve high sensitive detection system.

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

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

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

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

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

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

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

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

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

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

قياس تركيز غاز الرادون والثورون في المنازل والمستشفيات والمراكز الصحية في محافظة البصرة العراق

Author name: حسام نجم عبود
Supervisor name: عيسى جاسم محمد الخليفة
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University Of Basrah - College Of Education For Pure Sciences - Department Of Laser Physics
Language: Arabic
University location: Basrah
First pages:

استقصاء خصائص المفرق الهجيني Cd1 - xZnxS/Si للتطبيقات الفوتوفولتائية == Investigation of Cd1 - xZnxS/Si Heterojunction Properties for Photovoltaic Applications

Author name: رسل عبد الامير غازي مصحب
Supervisor name: ناهدة بخيت حسن
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Babylon - College Of Science - Physics Department
Language: English
University location: Babylon
First pages:
Abstract: تم تحضير اغشيةCd1 - xZnxS باستخدام تقنية الرش الكيميائي الحراري وهي طريقة سهلة الاستخدام ومناسبة للترسيب على مساحات كبيرة . استخدمت خلات الكادميوم المائية كمصدر للحصول على الكادميوم وخلات الخارصين المائية كمصدر للحصول على الخارصين والثيوريا مصدر للحصول على الكبريتيد. تم تحضير مزيج الاغشية Cd1 - xZnxS بنسب حجمية مختلفة من (x) 0,0.2 ,0.4 ,0.6 ,0.8 ,1] [x= على قواعد زجاجية وسليكونية نظيفة ومسخنة عند درجة حرارة اساس 360) oC) وقد استخدم الهواء الجوي كغاز حامل . تم فحص التركيب البلوري للاغشية المحضرة بطريقة حيود الاشعة السينية ( XRD) واوضحت النتائج ان جميع الاغشية المحضرة كانت متعددة التبلور واظهرت تحسن البنية البلورية من حيث نقصان عدد القمم واختفاء بعضها وهذا مؤشر لتحسن خصائص الاغشية المحضرة. درست طبوغرافية الاسطح للاغشية المحضرة باستخدام مجهر القوى الذرية (AFM) والمجهر الالكتروني الماسح ) FESEM) ومبدد الطاقة للاشعة السينية (EDX) . الحجم الحبيبي للغشاء الرقيق Cd1 - xZnxS يزداد مع زيادة النسب الحجمية من (ZnS) . كذلك ان زيادة نسبة (ZnS) تؤدي الى زياده خشونة السطح، فحص (EDX) اظهر احتواء الاغشية على عناصر (Cd, Zn, S) كما هو متوقع ، مشيرا الى تشكيل اغشيه S Cd1 - x Znx عالية النقاوة. تم دراسة الخصائص البصرية للاغشية المحضرة بسمك (160 ± 3) nmباستخدام قياسات النفاذية البصرية في المنطقة الطيفي (300 - 1100) nm. نتائج النفاذية كانت اكبر من 94%. فجوة الطاقة المباشرة للــ (CdSpure) تساوي 2.61) eV) ، والتي تزداد مع زيادة النسب الحجمية من (ZnS) حيث ان فجوة الطاقة لل( (ZnSpureتساوي 3.41) eV) .الثوابت البصرية كمعامل الانكسار ومعامل الخمود وثوابت العزل تم حسابها لجميع الاغشية المحضرة. الخصائص الكهربائية مثل التوصيلية الكهربائية المستمرة وتاثير هول تم دراستها . اشارت النتائج ان الاغشية من النوع الموجب ( p - type ) وتمتلك طاقتي تنشيط ( Ea1,Ea2 )، وقد وجد ان التوصيلية الكهربائية المستمرة تقل مع زيادة نسب حجمية من (ZnS). قيست سعة الانحياز العكسي للمفرق الهجين Cd1 - x ZnxS /n - Si كدالة لفولتية الانحياز وبتردد (1) MHz ، وقد دلت هذه النتائج على ان المفرق من النوع الحاد، لوحظ نقصان السعة بزيادة جهد الانحياز العكسي كذلك تزداد السعة (334 - 577) pF مع زيادة النسب الحجمية من (ZnS) ، بينما يقل عرض منطقة النضوب مع زيادة النسب الحجمية من (ZnS) . ووجد ان جهد البناء الداخلي تقل قيمته من (0.7 - 0.27) Volt مع زيادة النسب الحجمية من (ZnS). بينت خواص تيار - فولتية للمفرق الهجين (CdS)1 - x (ZnS)x /n - Si بان تيار الظلام الامامي يتغير اسيا تقريبا مع فولتية الانحياز ويتفق المفرق المصنع مع نموذج اعادة الاتحاد - الانتفاق ويظهر الانحياز العكسي توقف طفيف ثم فولتية انهيار تدريجيا. كذلك يلاحظ تناقص عامل المثالية وتيار الاشباع مع زيادة النسب الحجمية من (ZnS). درست خواص تيار الدائرة القصير وفولتية الدائرة المفتوحة حيث وجدنا ان Jsc وVocتزداد قيمتهمزايادة النسب الحجمية من (ZnS) وقد فسر سبب ذلك بوجود تغير في التركيب للاغشية وكذلك تحسن طبقة التداخل بين p - (CdS)1 - x(ZnS)x وn - Si .درست الخصائص الطيفية للمفرق الهجين Cd1 - xZnxS /n - Si ووجدنا ان قيم الاستجابة الطيفية , الكشفية النوعية والكفاءة الكمية تقل وتزحف باتجاه الاطوال الموجية الطويلة مع زيادة نسب حجمية من (ZnS) ، بينما تزداد القدرة المكافئة للضوضاء مع زيادة النسب الحجمية من (ZnS). من خلال قياسات الخصائص التحسسية للاغشية الرقيقة لغاز ( NO2 ) اظهرت تحسسية جيدة عند حرارة تشغيل (100 - 200)oC ،ايضا تحسسيه الاغشية للغازات تقل بزياده تركيز ZnS عند oC (200) وان تغيير درجة حرارة التشغيل تؤدي الى تغيرات واضحة في تحسسية الاغشية. | Cd1 - xZnxS thin films were prepared by using a chemical spray pyrolysis technique, which is a simple, inexpensive and suitable technique for large deposition area.The cadmium acetate was used as a source of cadmium, the zinc acetate was used as a source of zinc and theoria was used as a source of sulfide. Mixed Cd1 - xZnxS thin films with different Vol.% of (x) (x= 0,0.2,0.4,0.6,0.8 and 1) has been prepared on clean glass and silicon substrate at 360 ºC with atmospheric air as the carrier gas. The crystal structures of the deposited films were examined by X - ray diffraction analysis. The results show that all the prepared films are polycrystalline structure,and it has shown improvement in the crystal structure in terms of decreasing the reflection peaks and disappearance of some peaks .This refers to the improvement in the properties of the films. The surface morphology of the deposits films has been studied by using atomic force microscope(AFM),Field emission scanning electron microscope (FESEM) and energy dispersive X - ray(EDX).The grain size of the Cd1 - xZnxS thin films increases with increasing of ZnS Vol.% , also the increasing ZnS Vol.% leads to increase in the surface roughness. (EDX) shows that all the films contain the elements (Cd, Zn and S) as expected, indicating formation of the Cd1 - xZnxS films with high purity films with good stoichiometry. The optical properties of the films, which were prepared with thickness of (160±3) nm,have been determined by using the optical transmittance measurements in the spectral region from (300 - 1100) nm. Transmittance results were upper than 94% and direct energy gap for (CdS pure) equal (2.61) eV, it increases with increasing ZnS of Vol.% where energy gap for (ZnS pure) equal (3.41)eV. The optical constants such as refractive index, extinction coefficient and dielectric constant have been calculated for all prepared films. The electrical properties include D.C conductivity and Hall effect were studied. The results show that the prepared films were p - type , and have two activation energies (Ea1 , Ea2).It is found that the electrical D.C conductivity decreases with the increase of the ZnS Vol.%. The reverse bias capacitance for p - Cd1 - xZnxS /n - Si heterojunction was measured as a function of bias voltage at frequency 1MHz, and we note that these heterojunction are abrupt. The capacitance decrease with increasing the reverse bias voltage, also it increases from (334 to 577) pF with increase of the ZnS Vol.%. while the depletion width decreases with increasing of the ZnS Vol.%. The value of built - in potential decreases from (0.7 to 0.27) Volt with increasing of the ZnS Vol.%. For p - Cd1 - xZnxS/n - Si heterojunction under dark conditions shows that forward bias current variation approximately exponentially with voltage bias.This conforms with tunneling - recombination model.The ideality factor and saturation current were calculated and notice the value decrease with increasing of the ZnS Vol.%. The short - circuit current density and open - circuit voltage have been studied, where the Jsc and Voc increases with increasing of the ZnS Vol.%. The spectral response of Cd1 - xZnxS/n - Si was studied. The values of responsivity, specific detectivity and quantum efficiency decreases and shifts to longer wavelength with increase of the ZnS Vol.%. While the noise equivalent power increases with increasing the ZnS Vol.%. From the sensing properties measurements of thin films show that films were good sensors for gas (NO2) at operation temperature (100 - 200) oC , also sensitivity of films for gases decreases with increases the concentration of ZnS at (200) oC. The variation of the operating temperature of the films have led to a significant change in the sensitivity of the sensor.

المعالجة شبه الكلاسيكية والكمية لتفاعلات الاندماج والتفكك لبعض النوى الخفيفة والمتوسطة == Semiclassical and Quantum Treatment of Fusion and Breakup Reactions of some light and Medium Nuclei

Author name: مالك صالح محيميد الحمداني
Supervisor name: خالد حسين هاتف العطية | فؤاد عطية مجيد
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Babylon - College Of Science For Girls - Department Of Laser Physics
Language: English
University location: Babylon
First pages:
Abstract: في هذه الدراسة ، اجريت حسابات مقطع الاندماج الكلي σ_fus وتوزيع حاجز الاندماج D_fus واحتمالية الاندماج P_fus للانظمة 4He+233U، 6He + 64Zn ، He+209Bi6، 7Li+59Co،B+237Np11، C+48Ti13، 14N+59Co، N+54Fe15، 16O+46Ti، 18O+58Ni، 18O+60Ni، O+64Ni18، O+208Pb18، F+40Ca19، 27Al+45Sc، 30Si+64Ni، 37Cl+25Mg، 46Ti + 46Ti، Ti+60Ni50، 58Ni + 28Si، 58Ni + 54Fe، 58Ni+60Ni، 60Ni+100Mo . اجريت الحسابات باستخدام مقاربتين : اولا، المقاربة الشبه الكلاسيكية والتي تعتمد بالاساس على نظرية Alder وWinther والتي استعملت لتعالج التهيجات الكولومية للنويات والتي تسمى بطريقة اقتران القنوات للاستمرار المقطع (CDCC). الحسابات تم انجازها في حالة غياب وتضمين تاثيرات الاقتران. ان المقاربة شبه الكلاسيكية تستعمل تقريبWenzel وKramers وBrillouin (WKB) لمعالجة احتمالية الاندماج الكلاسيكية بينما الحركة الذاتية تمت معالجتها عن طريق معادلة شرودنكر المعتمدة على الزمن. ثانيا، المقاربة للميكانيك الكمي حيث تعاملنا مع المسالة مستخدمين حسابات الميكانيك الكمي الشاملة والتي انجزت الحسابات في حالة عدم تضمين تاثيرات الاقتران وكذلك مع الاخذ بنظر الاعتبار تاثيرات الاقتران.انجزت الحسابات باستعمال البرامج الحاسوبية SCF للحسابات الشبه كلاسيكية وQMCC لحسابات الميكانيك الكمي. البرنامج الحاسوبي SCF والذي كتب بالاصل من قبل H. D. Marta ومجموعته البحثية باستعمال لغة الفورتران ، بينما البرنامج الحاسوبي QMCC والذي كتب بالاصل من قبل L. F. Canto ومجموعته البحثية باستعمال لغة الفورتران. قمنا بتعديل هذه البرامجيات الحاسوبية لتاخذ بنظر الاعتبار الحركة النسبية بين الهدف والقذيفة. طريقة مربع كاي (chi - square) استعملت لايجاد مدى تقارب حساباتنا النظرية بالمقارنة من البيانات العملية الى جانب ذلك قمنا باضافة توزيع حاجز الاندماج ليحسب مباشرة من هذه البرامج. لقد كتب برنامج فرعي بلغة فورتران 90 لحساب توزيع حاجز الاندماج D_fus باستعمال طريقة الفرق بين ثلاث نقاط وهذا البرنامج الفرعي تم ربطة مع البرنامج الحاسوبي QMCCلكن في برنامج SCF اخذنا المشتقة الثانية لـ (Eσ_fus) حيث σ_fus هي بصيغة وونك.لقد قورنت حسابات مقطع الاندماج الكلي σ_fus وتوزيع حاجز الاندماج D_fus واحتمالية الاندماج P_fus باستعمال طريقة مربع كاي (chi - square) لكلا التقاربين الشبه الكلاسيكي والميكانيك الكمي الشامل وبكلتا الحالتين بغياب الاقتران وبوجود الاقتران مع البيانات العملية. قورنت الحسابات شبه كلاسيكية وحسابات الميكانيك الكمي الشاملة لمقطع الاندماج الكلي σ_fus وتوزيع حاجز الاندماج D_fus واحتمالية الاندماج P_fus مع البيانات العملية المتوفرة لكل نظام، وجد ان حسابات قنوات الاقتران للميكانيك الكمي في توافق اكثر مع البيانات العملية من الحسابات شبه الكلاسيكية لاغلب الانظمة قيد الدراسة. | In this study, the calculations of the total fusion cross section σ f us, the fusion barrier distribution Df us and the fusion probability Pf us, for the reactions4He+233U, 6He+64Zn, 6He+209Bi, 7Li+59Co, 11B+237Np, 13C+48Ti, 14N+59Co,15N+54Fe, 16O+46Ti, 18O+58Ni, 18O+60Ni, 18O+64Ni, 18O+208Pb, 19F+40Ca,27Al+45Sc, 30Si+64Ni, 37Cl+25Mg, 46Ti+46Ti, 50Ti+60Ni, 58Ni+28Si,58Ni+54Fe, 58Ni+60Ni, 60Ni+100Mo have been conducted. The calculations have been performed by using two approaches : Firstly, the semiclassical approach which based on Alder and Winther (AW) theory originally used to treat the Coulomb excitation of nuclei which is called Continuum - Discretized Coupled Channels (CDCC) method. The calculations have been preformed in the absence of coupling effects and in the case of the coupling effects were included. The semiclassical calculations used Wentzel, Kramers and Brillouin (WKB) approximation to treat the classical probability while the intrinsic dynamics is handled by the time - dependent Schrodinger equation.Secondly, the quantum mechanical approach, in which we treat the problem using the full quantum mechanical calculations. The calculations were performed in the case of no coupling included and with the coupling effects were taken into consideration.The calculations have been performed by using SCF code for semiclassical and QMCC code for quantum mechanical calculations. The SCF code is originally written by H. D. Marta and his collaborators using fortran language, while the QMCC code is originally written by L. F. Canto and his collaborators using fortran language. A sub - program has been written by Fortran 90 language to calculate the fusion barrier distribution Df us using the three - point - differencemethod. This sub - program has been implemented in both SCF and QMCCcodes.The calculations of the total fusion cross section σ f us, the fusion barrier distribution Df us and the fusion probability Pf us, have been compared by means of chi - square method for both semiclassical and quantum mechanical approaches in both no - coupling and coupling case with the corresponding experimental data. It is found that the quantum mechanical coupled channels calculations are in more agreement with the experimental data than the semiclassical calculations for most studied systems

خصائص اغشية (SnO2) 1 - x (ZnO) x النانوية التركيب الرقيقة وتطبيقاتها == Characterizations of Nanostructure (SnO2)1 - x(ZnO)x Thin Films and Their Applications

Author name: زهراء عادل جواد المعموري
Supervisor name: ناهدة بخيت حسن
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Babylon - College Of Science - Physics Department
Language: English
University location: Babylon
First pages:
Abstract: In this work, mixed (SnO2)1 - x(ZnO)x thin films were prepared by using ahomemade chemical spray pyrolysis technique, which was a simple, inexpensive and suitable technique for large deposition area. The Tin (II) Chloride Dihydrate SnCl2.2H2O was used as a source of tin oxide particles, and the zinc acetate dehydrate Zn(CH3COO)2.2H2O was used as a source of zinc particles. Mixed (SnO2)1 - x(ZnO)x thin films with different Vol.% of (x) [0,0.2,0.4,0.6,0.8,1] has been prepared on clean preheated glass and silicon substrate at 400 ºC with atmospheric air as the carrier gas. The crystal structures were examined by X - ray diffraction analysis. The result showed that all the prepared films were polycrystalline structure. It was observed that the granular size of the SnO2 membrane was greater than the granular size of ZnO the membrane, indicating that the ZnO membrane in the selected conditions was better crystallized. The surface morphology of the deposits films have been studied by using atomic force microscope (AFM), scanning electron microscope (SEM) and energy dispersive X - ray (EDX). The grain size of the (SnO2) nanoparticles observed at the surface depended on (x), which increase with increasing of ZnO Vol.%, also the increasing ZnO Vol.% lead to an increase in the surface roughness. (EDX) shows that all the films contain the elements (Sn, Zn and O) as expected, indicating formation of the (SnO2)1 - x(ZnO)x films with high purity. The optical properties of the films, which were prepared with thickness of (190 ± 3 nm), have been determined by using the optical transmittance measurements in the spectral region from 300 to 1100 nm. Transmittance results were upper than 95% which make these films suitable for sensor applications. Direct energy gap for (SnO2) equal 3.1 eV, it increases with increasing ZnO Vol.%. The optical constants such as refractive index, extinction coefficient and dielectric constant have been calculated for the prepared films. The electrical properties included D.C conductivity and Hall effect were studied. The results showed that the prepared films were n - type, and have two activation energies (Ea1 , Ea2). It was found that the electrical D.C conductivity increased with the increase of the ZnO Vol.%. The reverse bias capacitance for (SnO2)1 - x(ZnO)x/p - Si heterojunction was measured as a function of bias voltage at frequency 1MHz, and it was indicated that these heterojunction were abrupt. The capacitance increases with increasing the reverse bias voltage, also the capacitance increases from 185 pF to 314 pF with increase of the (x), while the depletion width decreasing with increasing (x). The value of built - in potential decreases from 0.9 to 0.3 Volt with increasing of the ZnO Vol.%. The electrical characteristics of the (SnO2)1 - x(ZnO)x/p - Si heterojunction have been studied, where current - voltage characterization under dark conditions showed that forward bias current variation approximately exponentially with voltage bias. This conforms with tunneling - recombination model, and reverse bias showed little stop and soft breakdown voltage. Also the product showed that current decreases with increasing Vol.% of (x). The efficiency and the fill factor of (SnO2)1 - x(ZnO)x/ p - Si of solar cell was measured. The calculations of the solar cell show that efficiency was the highest value when mixing where we observed a clear increase in efficiency ranging from (1.87 - 5). The fill factors of the devices for all types were in range of (0.25 - 0.454). The results showed that the efficiency of the solar cell is higher than its value at x = 0.8.From the sensing properties measurements of thin films for gas ( NO2 ) show that the films was good sensor to this gas at (25 - 200)oC. The best sensitivity of mixed thin films was 81% at x=1. The variation of the operating temperature of the films have led to a significant change in the sensitivity of the sensor with an ideal operating temperature.

تصنيع وخصائص متراكبات بولي فاينيل الكحول - كاربوكسي مثيل سليلوز اكاسيد المعادن النانوية كمؤثر للمضادات البكتيرية == Fabrication and Characterizations of PVA - CMC Metal Oxide Nanocomposites as Antibacterial Effect

Author name: قيصر مهدي جبر معارج الجبوري
Supervisor name: رحيم كعيد كاظم حسين المرشدي | مجيد علي حبيب راضي الخفاجي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Babylon - College Of Science - Physics Department
Language: English
University location: Babylon
First pages:
Abstract: في هذه الاطروحة تم تحضير نوعين من المتراكبات النانوية (PVA - CMC - ZnO) و(PVA - CMC - CuO) بطريقة صب المحلول. حضر الخليط البوليمري (بولي فينيل الكحول - كاربوكسي مثيل سليلوز) بتراكيز مختلفة من بولي فينيل الكحول (80 wt.%) وكاربوكسي مثيل سليلوز (20 wt.%) وكذلك تم اضافة اكاسيد الزنك واكاسيد النحاس النانوية للخليط البوليمري بنسب مئوية مختلفة وهي (3,6,9,12) . تمت دراسة تاثير كل من جسيمات اوكسيد الزنك واوكسيد النحاس النانوية على الخواص التركيبية والكهربائية (المستمرة والمتناوبة) والبصرية للخليط البوليمري (PVA - CMC) بتراكيز مختلفة. وتم تصنيع متحسسات الرطوبة ، مضادات البكتيريا ومواد كهروضغطية كتطبيقات.لقد اظهرت صور المجهر الضوئي وصور مجهر الماسح الالكتروني ان كل من اكاسيد الزنك النانوية واكاسيد النحاس النانوية تتوزع بشكل متجانس في الخليط البوليمري . واظهرت منحنيات تحويلات فورير للاشعة تحت الحمراء انه لا يوجد تفاعل كيميائي بين الخليط البوليمري والجسيمات النانوية المضافة. تم حساب الخواص الكهربائية المستمرة للمتراكبات النانوية لتراكيز ودرجات حرارة مختلفة.وقد بينت النتائج ان التوصيلية الكهربائية المستمرة للخليط البوليمري (PVA - CMC) ازدادت بزيادة تراكيز كل من اكاسيد الزنك النانوية واكاسيد النحاس النانوية ودرجات الحرارة.وقد تبين ان طاقة التنشيط قلت بزيادة تراكيز كل من اكاسيد الزنك النانوية واكاسيد النحاس النانوية. درست الخواص الكهربائية المتناوبة في مدى تردد (100Hz - 5MHz) في درجة حرارة الغرفة. اظهرت النتائج التجريبية ازياد كل من ثابت العزل الكهربائي وفقدان العزل الكهربائي والتوصيلية الكهربائية المتناوبة للخليط البوليمري (PVA - CMC) بزيادة تراكيز كل من اكاسيد الزنك النانوية واكاسيد النحاس النانوية.في حين يقل كل من ثابت العزل الكهربائي وفقدان العزل الكهربائي للمتراكبات النانوية (PVA - CMC - ZnO) و(PVA - CMC - CuO) بزيادة تردد المجال الكهربائي المسلط , كما تزداد التوصيلية الكهربائية المتناوبة بزيادة التردد. وقد بينت النتائج التجريبية للخواص البصرية للمتراكبات النانوية (PVA - CMC - ZnO) و(PVA - CMC - CuO) زيادة الامتصاصية ومعامل الامتصاص ومعامل الخمود ومعامل الانكسار وثوابت العزل الحقيقي والخيالي للخليط البوليمري (PVA - CMC) بزيادة تراكيزكل من اكاسيد الزنك النانوية واكاسيد النحاس النانوية. في حين تقل النفاذية وفجوة الطاقة للانتقال غير المباشر(المسموح والممنوع) بزيادة تراكيزكل من اكاسيد الزنك النانوية واكاسيد النحاس النانوية. لقد بينت نتائج تطبيقات متحسسات الرطوبة للمتراكبات النانوية (PVA - CMC - ZnO) و(PVA - CMC - CuO) ان المقاومة السطحية تقل بزيادة التراكيز المضافة والرطوبة النسبية. وكنتيجة لذلك، فانها تمتلك حساسية عالية للرطوبة. اختبرت المتراكبات النانوية (PVA - CMC - ZnO) و(PVA - CMC - CuO) كمضادات لبكتيريا موجبة غرام (المكورات العنقودية الذهبية) وسالبة غرام (الاشريشيا القولونية). اظهرت النتائج ان منطقة التثبيط تزداد بزيادة تراكيز كل من اكاسيد الزنك النانوية واكاسيد النحاس النانوية.كما بينت نتائج تطبيقات المواد الكهروضغطية للمتراكبات النانوية (PVA - CMC - ZnO) و(PVA - CMC - CuO) ان المقاومة الكهربائية تقل بزيادة التراكيز المضافة والحمل المطبق. وكنتيجة لذلك، فانها تمتلك حساسية عالية للاجهاد الميكانيكي. | In this thesis the two types of (polyvinyl alcohol - Carboxymethyl cellulose - Zinc oxide) and (polyvinyl alcohol - Carboxymethyl cellulose - Copper oxide) nanocomposites have been prepared by solution casting method. The (PVA - CMC) blend was prepared for different concentrations (80 wt.%)PVA and (20 wt.%) CMC as well Zinc oxide and Copper oxide nanoparticles (NPs) were added to (PVA - CMC) blend with different weight percentages as (3,6,9 and 12) wt.%.The effect of Zinc oxide and Copper oxide nanoparticles additives on structural, (D.C and A.C) electrical and optical properties of (PVA - CMC) blend have been studied. Humidity sensors, antibacterial activities and piezoelectric applications have been fabricated. Optical microscope and scanning electron microscope images indicate that the Zinc oxide and Copper oxide nanoparticles additives distribution was homogeneous in the blend. FT - IR indicate that no change on chemical structures between the blend and the additives.The D.C electrical properties of (PVA - CMC - ZnO) and (PVA - CMC - CuO) nanocomposites were investigated with different additive concentrations and temperatures. The results showed that D.C electrical conductivity of (PVA - CMC) blend increases with increasing of Zinc oxide and Copper oxide NPs concentrations and temperatures. The activation energy decreased with increased the concentration of the Zinc oxide and Copper oxide NPs. A.C electrical properties of these nanocomposites were studied in frequency range (100Hz - 5MHz) at room temperature. The experimental results showed that the dielectric constant, dielectric loss and A.C electrical conductivity of (PVA - CMC) blend increased with increasing the Zinc oxide and Copper oxide NPs concentrations. The dielectric constant and dielectric loss of (PVA - CMC - ZnO) and (PVA - CMC - CuO) nanocomposites decreased with increasing of the frequency of applied electric field, while A.C electrical conductivity increases with increasing of frequencies. The experimental results of optical properties for (PVA - CMC - ZnO) and (PVA - CMC - CuO) nanocomposites showed that the absorbance, absorption coefficient, extinction coefficient, refractive index, real and imaginary dielectric constants of (PVA - CMC) blend increased with increasing of the additive of Zinc oxide and Copper oxide NPs concentrations, while the transmittance and (allowed and forbidden ) energy gap decreased with increasing of the Zinc oxide and Copper oxide NPs concentrations. The results of applications for (PVA - CMC - ZnO) and (PVA - CMC - CuO) nanocomposites as humidity sensors showed that the surface resistance decreases with increasing of additive concentrations and relative humidity. As a result, humidity sensors have higher sensitivity for humidity. The antibacterial properties of the (PVA - CMC - ZnO) and (PVA - CMC - CuO) nanocomposites tested against gram - positive (S. aureus) and gram - negative (E. coli) bacterial. The results showed the inhibition zone increased with increasing of the concentrations of Zinc oxide and Copper oxide NPs. The results of applications for (PVA - CMC - ZnO) and (PVA - CMC - CuO) nanocomposites as piezoelectric showed that the electrical resistance decrease with increasing of additive concentrations and applied load. As a result, pressure sensors have higher sensitivity for mechanical stress.

موديل رياضي لحساب الجرعة الاشعاعية المستخدمة لعلاج الخلايا الخبيثة وتطوير معدل تحسين الحساسية بمساعدة الجسيمات النانوية == Mathematical Model for Calculating Radiation Dose used to Treat Malignant Cells and Improved SER with Aid of Nanoparticles

Author name: طالب عبد الرضا عبد الواحد
Supervisor name: نهاد عبد الامير صالح المعموري
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Babylon - College Of Science - Physics Department
Language: English
University location: Babylon
First pages:
Abstract: Radiotherapy is one of the steps for cancer treatment, which involves using high energy photons produces from radioactive source or linear accelerator. Because of limited tolerance of human organs for radiation appears a need to enhance radiotherapy by increasing absorbed dose inside human target. One of the most promising methods currently used involving contrast agent like nanoparticles to enhance the radiation tolerance inside the tumor. Interaction between high energy photon (E> 1.022MeV) and nanoparticle inside specific organ produces electron and positron according to pair production. This thesis aims to create an enhancement in the cross section of the tumor cells by nanoparticles like gold nanoparticles, gadolinium nanoparticles, silver nanoparticles and titanium nanoparticles. The goal behind using nanoparticles is to increase the dose received by the tumor cells without increasing the dose received in surrounding healthy tissue.The importance of this method is to reduce the number of radiotherapy sessions (time) that are given to patients with cancer then result in reducing the side effects of radiation therapy. This is done by increasing sensitivity enhancement ratio (SER). SER is the ratio of survival cells to initial cells for irradiation without and with nanoparticles. The direct injection of nanoparticles into malignant tumor is considered a perfect method to increase (SER).Each gold, gadolinium, silver and titanium nanoparticles were used as radio - sensitizing agents to increase (SER), the greater number of malignant cells destroyed by radiation with the aid of nanoparticles produced the greater the amount of (SER). The contrast agent loaded to malignant tumor interacts with X - ray photons whose energy ranged from 2MeV to 20 MeV. This thesis recorded many SER depending on the typeof contrast agent and energy of X - ray. Each nanoparticle was irradiated with photons energy 2MeV, 4Mev, 6 MeV, 8 MeV, 10 MeV, 15 MeV, 20MeV, respectively. The same approach was applied with each of brain, breast, lung, prostate, and ovary tumors.™ The brain results showed an average enhancement in SER as follows : 11.63 when using TiNPs, 13.24 with using AgNPs, 13.72 with using GdNPs, 14.26 with using AuNPs. The breast shows average SER results as coming 10.79 to TiNPs, 12.45 to AgNPs, 12.95 to GdNPs finally 13.50 to AuNPs and average SER for lung as next 10.86 to TiNPs, 12.51to AgNPs, 13.03to GdNPs and 13.59to AuNPs. Average SER results of ovary as coming 10.85with TiNPs, 12.52 with AgNPs, 13.02 with GdNPs and 13.58 with AuNPs. Final average SER to prostate arranged as 10.83 to TiNPs, 12.47 to AgNPs, 12.93 to GdNPs finally 13.50 to AuNPs. From these results can be concluded higher SER response of organs to nanoparticles with high energy X - ray are arranged as follow in first degree AuNPs, secondly GdNPs, third AgNPs and finally TiNPs.

استخدام تقنيات فيزيائية لتشخيص سرطان الثدي في نماذج من الدم == Using of Physical Techniques for Diagnosis of Breast Cancer to Blood Samples

Author name: شيماء عواد كاظم حميدي
Supervisor name: خالد حسين هاتف العطية
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Babylon - College Of Science For Girls - Physics Department
Language: English
University location: Babylon
First pages:
Abstract: Breast cancer is one of the most common malignancies in women. In this thesis we employ fourth techniques for diagnosing the breast cancer early; UV - visible spectroscopy, Fourier Transform InfraRed (FTIR - ATR) technique, Atomic Absorption Spectrophotometer (AAS) and Solid - State Nuclear Track detectors (SSNTDs) (CR - 39NTD),was took blood samples to females whom newly diagnosis breast cancer ,control groups and females whom took chemotherapy at aged (33 - 74) years in the Middle Euphrates Center Cancer of Al Najaf province : UV - visible spectroscopy technique : we have found fourth types of bands in the spectra of this technique for female of breast cancer ,female who take chemotherapy and healthy subjects . First, second and third band regions cover the ultraviolet behavior of proteins but fourth band does not show absorbance of proteins, we noted appeared and disappeared some bands also increased the absorbance in patients which are represented early an evidence for diagnosing breast cancer.Fourier Transform Infrared (FTIR - ATR) technique : By employed this technique we found the absorbance of patients with new breast cancer larger than the absorbance of health subjects was found high statistically significant for wavenumber(ʋ) cm - 1 (1246.1 - 1241.4cm - 1) , (1536.4 - 1530.3cm - 1), and ( 3297.3 - 3277.0cm - 1) where was p - value < 0.05 while (698.6 - 667.8 cm - 1) and (2937.8 - 2925.5 cm - 1) was non - significant statistically p - value was larger than 0.05 also getting shift in wavenumber between two cases.Atomic Absorption Spectrophotometer (AAS) technique : by using itcalculated the levels of the (trace elements) metal ions(Cu ,Zn ,Fe ,Mnand Ni) has a potential role in early detection and monitoring of breastcancer where we found high increased in concentration of Iron in patientsand less in copper compared with health while high decreased inconcentration in Zinc, Manganese and Nickel in patients compared withhealth .Solid - State Nuclear Track detectors (SSNTDs) technique : we calculated by using it the mean of concentration of radon and activity of radon for females of control groups , newly diagnosis breast cancer and females whom took chemotherapy which was ARn (Bq) health group(0.097895) > ARn (Bq) new case(0.079873) > ARn (Bq) take chemotherapy(0.036443) > . We have found the Levene's Test (F) was Significant for the comparative between normal case and the case of take chemotherapy( .012) less than 0.05, the Levene's Test (F) was higher significant for the comparative between new case of breast cancer and the case who take chemotherapy (.001) much less than 0.05 while non - significant statistically between normal and new case(.731) larger than 0.05.

دراسة بعض الخصائص الفيزيائية p - MgxZnO1 - x/n - Si للكاشف الضوئي والمتحسس الغازي == Study of Some Physical Properties of p - MgxZnO1 - x/n - Si Photodetector and Gas Sensor

Author name: سليم حمزة طرير جبر
Supervisor name: عبد العزيز عبيد موسى العكيلي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Babylon - College Of Science - Physics Department
Language: English
University location: Babylon
First pages:
Abstract: في هذا العمل تم تحضير اغشيةMgxZnO1 - x باستخدام تقنية الرش الكيميائي الحراري وهي طريقة ملائمة ومناسبة للترسيب على مساحات كبيرة . وتم انماء مزيج محاليل MgxZnO1 - x بنسب حجمية مختلفة (0 ،30 ،50 ،70 و90)% ومرسبه على قواعد زجاجية وسليكونية وعند درجات حرارة مختلفة (400، 450 و500) درجة مئوية وتم تثبيت السمك من خلال تثبيت عدد الرشات وكان سمك جميع الاغشية يتراوح بين (5±80) نانومتر وقد تم اجراء الرش باستخدام غاز النيتروجين . تم تشخيص التركيب البلوري للاغشية بتقنية حيود الاشعة السينية (XRD) واظهرت النتائج ان جميع الاغشية المحضرة كانت متعددة التبلور واظهرت تحسن في البنية البلورية من خلال تغير درجات الحرارة. درست طبوغرافية السطح للاغشية باعتماد مجهر القوى الذرية (AFM) والمجهر الالكتروني الباعث الماسح FESEM)) ومشتت الطاقة للاشعة السينية (EDX). ان زيادة نسبة محتوى المغنيسيوم في الاغشية ادت الى نقصان خشونة السطح . وان (EDX) اظهرت احتواء الاغشية على عناصر( Si، N ،O ، Zn وMg ) كما هو متوقع . تم قياس استطارة رامان لاغشية MgxZnO1 - x/n - Si الرقيقة لمختلف نسب محتوى المغنيسيوم ، حيث اظهرت شدة ذات حزمتين cm - 1(601 و1202) المقابلة الى انماط استطارة رامان ذات الرتبة الاولى العليا E_2^high, ونمط الرتبة الثانية هو A1(LO) وهو نمط الرتبة الاولى بالنسبة لاوكسيد الزنك، اذ انه بزيادة محتوى المغنيسيوم الى اكثر من(50) % فان نمط الرتبة E_2^high سوف تنخفض شدته. وتمت دراسة الخصائص البصرية للاغشية المحضرة من خلال قياس النفاذية البصرية في المنطقة الطيفية (700 - 300) نانومتر، وكانت نتائج النفاذية تتراوح من (89 - 65)% عند زيادة محتوى المغنيسيوم من (30 - 90)% في درجة حرارة (400) درجة مئوية ، وتزداد النفاذية اكثر عند زيادة درجة الحرارة الى (500) درجة مئوية لتصبح من(95 - 84) % عند محتوى المغنيسيوم نفسه مما يجعلها ملائمة لتطبيقات المتحسسات الغازية. وتم قياس الامتصاصية والانعكاسية لجميع الاغشية وكانت تتناقص بارتفاع درجات الحرارة، بالاضافة الى ذلك تم قياس معامل الامتصاص لجميع الاغشية وكانت قيمته اعلى من cm - 1 (104) . وحسبت فجوة الطاقة المباشرة لاوكسيد الزنك النقي وكانت (3.18 ،3.21 و3.19) الكترون فولت التي تقابل درجات الحرارة (400، 450 و500) درجة مئوية على التوالي . وتم حساب الثوابت البصرية كمعامل الانكسار ومعامل الخمود وثابت العزل الحقيقي والخيالي لجميع الاغشية المحضرة. وتم حساب فجوة الطاقة البصرية من خلال مطياف الاستضائية وكانت القيم تتراوح بين (3.558 - 3.531) الكترون فولت، تم دراسة الخصائص الكهربائية كالتوصيلية الكهربائية المستمرة وتاثير هول، واظهرت نتائج قياسات تاثير هول ان غشاء اوكسيد الزنك النقي من النوع السالب (n - type) اما اغشية MgxZnO1 - x فهي من النوع الموجب(p - type) وتمتلك طاقتي تنشيط (Ea1 وEa2). تم قياس سعة كاشف MgxZnO1 - x /n - Si كدالة لفولتية الانحياز العكسي وبتردد يتراوح بين 0.6) (1 - ميكا هيرتز، واشارت تلك النتائج الى ان كاشف المفرق الهجين من النوع الحاد. كما وجد ان جهد البناء الداخلي تنخفض قيمته بزيادة محتوى المغنيسيوم وتزداد عند نسبة محتوى المغنيسيوم (90)% . واظهرت خصائص تيار - فولتية لكاشف MgxZnO1 - x /n - Si ان تيار الظلام الامامي يتغير اسيا مع فولتية الانحياز، كذلك لوحظ تناقص عامل المثالية وتيار الاشباع العكسي بزيادة محتوى المغنيسيوم في الاغشية في حين يزداد عند درجات الحرارة العالية كما تم في هذا العمل دراسة الخصائص الطيفية للكاشف ووجد ان قيم الاستجابة الطيفية ، الكفاءة الكمية والكشفية النوعية تزداد بزيادة نسبة محتوى المغنيسيوم ، بينما القدرة المكافئة للضوضاء تنخفض بزيادة محتوى المغنيسيوم . وظهرت قمم الاستجابية عند الطول الموجي (450) نانومتر وكانت تساوي الى (13.51) A/W وعند الطول الموجي (900) نانومتر وكانت تساوي الى (36.83)A/W . كما تم حساب الربحية للكاشف ووجد ان الكسب يزداد عند ارتفاع درجات الحرارة . وتم قياس تحسسية المتحسس لغاز NO2 في الهواء المحيط في منظومة استشعار الغاز . وتم فحص جميع العينات في نسبة %3 NO2 : الهواء وفولتية انحياز (6 (فولت. وكانت افضل نسبة اشابة لمحتوى المغنيسيوم %(5x=) ، ودرجة حرارة القاعدة السليكونية هي (400) درجة مئوية ودرجة حرارة تشغيل (200) درجة مئوية. وكانت اقصى تحسسية عند هذه النسبة هي (90.80)% وسرعة زمن الاستجابة هو (15.3) ثانية وزمن الاسترجاع هو (42.3) ثانية. | In this work MgxZnO1 - x thin films have been prepared using a chemical spraying pyrolysis (CSP) technique which is an easy and suitable way of deposition over large areas. Mixed solutions have been growth at different volumetric percentages (0, 30, 50, 70, and 90)% and deposited on glass and silicon substrates at temperatures (400,450, and 500) oC. The thickness was installed by installing the number of sprays. The thickness of all the films were (80 ±5) nm, have been using nitrogen gas. The crystal structure was examined by using X - ray diffraction (XRD) technique. The results showed that all the prepared were polycrystalline films, showing improvement in the crystal structure by change at temperature. Topography of the surface of the prepared films have been studied by using atomic force microscope (AFM), field emission scanning electron microscopy (FESEM), and energy dispersive X - ray spectroscopy (EDX). The increase in the percent of Mg - content in the films lead to decrease in surface roughness. (EDX) showed that films contain elements (Si, N, O, Zn, and Mg) as expected. Raman scattering have been measured for MgxZnO1 - x/n - Si thin films at different Mg - content. It exhibits two intense bands at (601 and 1202) cm - 1, corresponding to the E_2^high first - order Raman modes, and second - order mode the A1(LO) first - order mode of ZnO. As it increases Mg - content up to (50)%,the E_2^high mode the decrease in intensity. The optical properties of the films prepared by the optical transmittance measurements in the spectral region (300 - 700) nm. The results of the transmittance rang from (65 - 89)% when increasing the Mg - content from (30 to 90)% at substrate temperature of (400)oC and increased transmittance more when increase the temperature to become (84 - 95)% at the same Mg - content, which makes it suitable for applications gas sensors. Absorbance and reflectivity have been measured which were decreases by increasing temperatures. Absorption coefficient was measured for all the films, and its value more than (104) cm - 1. Direct energy gap was calculated for pure ZnO was (3.18 and 3.21 and 3.19) eV and the corresponding to substrate temperatures (400,450, and 500) oC respectively. The optical constants such as refractive index, extinction coefficient and dielectric constant have been calculated for all preparing films. The optical energy gap was calculated by photoluminescence spectrometer were few sensitive between (3.558 - 3.531) eV. The electrical properties such as D.C electrical conductivity and Hall effect have been studied, results showed measurements Hall that the pure ZnO film was negative type (n - type), while MgxZnO1 - x films were (p - type), and have two activation energies (Ea1,and Ea2). Capacity of MgxZnO1 - x/n - Si photodetector have been measured as a function of voltage reverse bias at frequency ranges (0.6 - 1) MHz. These results indicated that the photodetector is abrupt type. It was found that the value of built - in potential, decreases with increasing Mg - content and increases when Mg - content ratio (90%). The current - voltage characteristics of the MgxZnO1 - x/n - Si under dark conditions showed that forward bias current varied exponentially with voltage bias. The ideality factor and current saturation decreased with increasing Mg - content in the films whereas increased at high temperatures has been noticed. In this work the study of the spectral characteristics of the photodetector MgxZnO1 - x/n - Si and found that the spectral response values, quantum efficiency and specific detectivity increased with increasing Mg - content ratios, while the noise equivalent power (NEP) decrease when the Mg - content is increased. The beaks response appear at (450)nm equal to (13.51) A/W, and (900) nm equal to (36.83)A/W. It has been found that the gain for the MgxZnO1 - x/n - Si increases with increasing temperatures. The sensitivity of the MgxZnO1 - x/ n - Si to (NO2) gas in air ambient has been measured in the gas sensing system. All samples were tested at a ratio 3% NO2 : air and 6V bias voltage. The best ratio dopant of the Mg - content is x=(5)%, (200)oC operating temperature, and substrate temperature (400) oC of the silicon substrate. The maximum sensitivity is (90.80) % , fast response time is (15.3s) and recovery time is (42.3s).

التزامن ورنين التشاكه والعشوائي في الاتصالات البصرية العشوائية == Synchronization, Coherence And Stochastic Resonance In Chaotic Optical Communications

Author name: عيدان عاصي عبد الله الزبيدي
Supervisor name: قيس عبد الستار النعيمي
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Baghdad
Language: Arabic
University location: Baghdad
First pages:
Abstract: في هذا العمل، درسنا ثلاث ظواهر ناجمة عن الضوضاء، تم تطبيقها على نظام شواش، ليزر شبه والتزامن )CR) رنين التشاكه، (SR) موصل بتغذية الكتروبصرية عكسية هي : الرنين العشوائي التام، بالرغم من ان تطبيقاتها لازالت واعدة نسبيا الا انه ليس هناك شك في ان تصبح مستقبلا | In this work, we studied three noise - induced phenomena, applied to a chaotic semiconductor laser system with optoelectronics feedback regime : the stochastic resonance (SR), coherence resonance (CR) and noise - induced complete synchronization, while th

تحضير ودراسة بعض الخصائص الفيزياوية والميكانيكية لمتراكبات الايبوكسي الدقائقية الهجينة == The Preparation And Studying of Some Physical And Mechanical Properties For Hybrid Particular Composites Epoxy

Author name: سعاد حامد العيبي الربيعي
Supervisor name: عبد الحميد رحيم الصراف | بلقيس محمد ضياء الدباغ
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Baghdad - Ibn Al-Haytham College Of Education For Pure Sciences - Physics Department
Language: Arabic
University location: Baghdad
First pages:
Abstract: اجريت هذه الدراسة باستعمال راتنج الايبوكسي (Epoxy) نوع Thortex بوصفها مادة اساس للمواد المتراكبة وتم استعمال راتنج الفينول - فورمالديهايد نوع نوفولاك كمادة مطعمة ومسحــوق الزجاج (Glass - Powder) ومسحوق الالمنيوم (Al - Powder) بوصفها مواد مدعمة وبكسر حجم | This study was performed by using the Epoxy resin type Thortex as matrix to the composite materials with the phenol - formaldehyde type Novolac and with glass powder and the Alum. Powder were used as reinforced material of volume fraction amounting to 40%

تقنيات مطورة للكشف عن اورام الدماغ == Adaptive Techniques For Brain Tumor Detection

Author name: رباب سعدون عبدون
Supervisor name: صالح مهدي علي | لؤي كاظم عبود
General topic: Physics
Specific topic: Physics
Degree: Doctorate
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: تعتبر او ا رم الدماغ من احد الاسباب الرئيسية للوفاة الا انه من الممكن زيادة فرص البقاء على قيد الحياة اذا تم اكتشاف الورم بشكل صحيح في مرحلته المبك رة ومعالجته. الا ان عملية الكشف عن هذه الاو ا رم في صور الرنين المغناطيسي للدماغ تمتاز بالصعوبة في المناطق | Brain tumors are one of the major causes of death among people. The chances of survival can be increased if the tumor is detected correctly at its early stage. Detection of tumors in MRI of brain is not an easy task when the tumor is overlapped with dense
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