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تصنيع التراكيب النانوية Co3O4 / ZnO / Si للتطبيقات الكهروبصرية == Fabrication of Co3O4/ZnO/Si Nanostructures for Optoelectronic Applications

Author name: ابتهاج هادي حمود
Supervisor name: ازهار عناد حسن
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Technology - Department Of Applied Sciences
Language: English
University location: Baghdad
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تطوير نظام ذكي من اوكسيد الحديد - البوليمري النانوي بطريقة الاستئصال بالليزر وتوظيفه في توصيل دواء الباكليتاكسيل == Development of Smart Iron Oxide-Polymeric Nano-Carrier System by Laser Ablation and Functionalized as Targeted Paclitaxel Drug Delivery

Author name: رسل عبد الرسول عباس
Supervisor name: عدوية جمعة حيدر | شرف الدين الموسوي
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Doctorate
University: University of Technology - Department Of Applied Sciences
Language: English
University location: Baghdad
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فعالية المضاد البكتيري للجسيم النانوي الهجين Fe3O4 - Au المحضر بواسطة الاستئصال بالليزر == Anti-Bacterial activity of HyBrid Fe3O4-Au Nanoparticle prepared By Laser ablation

Author name: اسراء برهان راضي جليل
Supervisor name: خولة صلاح خشان | غسان محمد سليمان
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Doctorate
University: University of Technology - Department Of Applied Sciences
Language: English
University location: Baghdad
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تاثير التكثيف بالليزر على ثنائي اوكسيد السيليكون ذو البنية النانوية المحضر بتقنية Sol - Gel == The Effect of Laser Densification on Prepared Nanostructured SiO2 by Sol - Gel Technique

Author name: نور محمد عبد الملك
Supervisor name: محمد كريم ظاهر
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
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المنصة الورقية النانوية القابلة للحمل للكشف عن الملوثات == A Portable Nanomaterial Catalyst Based on Paper Platform to Detect Contamination

Author name: امين وليد جبار
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
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تصنيع متحسس بخار كيميائي المستند على فجوة الهواء لمتداخل ماخ - زنيدر == Fabricate of Chemical Vapor Sensor Based on Air - Gap of Mach - Zehnder Interferometer

Author name: ضحى نهاد عيسى
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

تكوين معاملات انكسار لا خطية متنوعة وفعالة لموائع نانوية مختلفة القواعد بواسطة التشعيع الليزري == Formation of Tunable Effective Nonlinear Indices of Nano Fluids at Various Bases by Laser Irradiation

Author name: اكرم شاكر احمد
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

تصميم العدسة الثنائية اللونية الملتصقة باقل الزيوغ اللوني ,الكروي والمذنب == Design of Chromatic Cemented Doublet Lens with Minimum Chromatic, Spherical and Coma Aberrations

Author name: ميديا اسماعيل سليمان الكاكـي
Supervisor name: ضياء نوري رؤوف
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Technology
Language: English
University location: Baghdad
First pages:

تحضير ودراسة مركبات جديدة لتطبيقات الخلايا الشمسية == Preparation and study new composite for solar cell applications

Author name: ماجد كاظم عبد الحمزة بنيان
Supervisor name: غالب عبد الوهاب الدهش | سيف محمد حسن الشريفي
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Babylon - College Of Science For Girls - Department Of Laser Physics
Language: Arabic
University location: Babylon
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تضمين الاتصالات لليزر شبه الموصل النقطي الكمي بوجود التغذية العكسية البصرية == Modulation Of Communication By Quantum Dot Semiconductor Laser(QDSL) With Optical Feedback

Author name: نور ضياء محود تقي علي
Supervisor name: باسم عبد اللطيف غالب | رياض ناجي علي
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Babylon - College Of Science For Girls - Department Of Laser Physics
Language: Arabic
University location: Babylon
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تحضير المتراكب النانوي اوكسيد الخارصين المعطم بالكاربون C/ZnO كنموذج لدراسة الخصائص والتطبيقات البصرية في ازالة بعض الصبغات الملوثة == Synthesizing Carbon-doping ZnO Nano Composites as a Model of Optical Properties and Applications of Some Pollutants Dyes Removal

Author name: اسراء برهان راضي جليل
Supervisor name: يىاس محمد الربيعي | اياد فاضل القيم
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Babylon - College Of Science For Girls - Department Of Laser Physics
Language: English
University location: Babylon
First pages:

دراسة تاثير اضافة عناصر (النيكل والفضة والكوبالت ) في توليف محاليل الحديد النانوية بطريقة الاستئصال بالليزر وتاثيرها على النشاط البكتيري == Study the Effect of (Ag,Ni,Co) Elements in Nano-Iron Solutions Syuthesized by Laser Ablation and its

Author name: سمية جعفر عباس عمران
Supervisor name: فيصل علي مصطفى البصام | سامي عبد الحسين هاتف حبانه
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Babylon - College Of Science For Girls - Department Of Laser Physics
Language: Arabic
University location: Babylon
First pages:

تصميم وبناء خلية وقود غشاء تبادل البروتون ذات حبيبات البلاديوم النانوية == Design and Construction of Proton Exchange Pd Nanoparticle Membrane Fuel Cell

Author name: مناف صالح مجيد
Supervisor name: محمد كريم ظاهر
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

دراسة تشخيصية لتراكيب نانوية لاغشية ثنائي اوكسيد السليكون الرقيقة المحضرة بتقنية السول - جل == Characterization Study of Nanostructured SiO2 Thin Films Prepared By Sol Gel Technique

Author name: حسن علوان خيون
Supervisor name: محمد كريم ظاهر
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

الكشف عن الرطوبة النسبية باستخدام مقياس التداخل لليف البلوري الفوتوني == Relative Humidity Detection Using Photonic Crystal Fiber Interferometer

Author name: سعاد صاحب هندال
Supervisor name: حنان جعفر طاهر
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

الخواص اللاخطية للموائع النانوية باستخدام تقنية حيود الليزر == Nanofluids Nonlinear Properties Using laser Diffraction Technique

Author name: مناف قاسم خلف
Supervisor name: مازن مانوئيل الياس
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

دراسة مصدر اشعاع قوس التفريغ الكهربائي المعزز بالليزر من القصدير السائل في المدى الطيفي للاشعة فوق البنفسجية القصوى == INVESTIGATION OF A LASER ASSISTED VACUUM ARC RADIATION SOURCE OF LIQUID TIN IN THE EUV SPECTRAL RANGE

Author name: وسام حسن مهدي العجيلي
Supervisor name: خليل ابراهيم حاجم
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

دراسة اداء جهاز مرشح الليف البصري ذو الحزمة الضيقة باستخدام محززات براك لليف البصري == Study the Performance of Implemented Narrow Band Optical Fiber Filter Using FBGs

Author name: مناف صالح مجيد
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

دراسة تجريبية للحيود الحراري في صبغات مختلفة == Experimental Study of Thermal Self - Defocusing in Different Dyes

Author name: عمار محمد طعيمة
Supervisor name: مازن مانوئيل الياس
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:
Abstract: This thesis discusses the effect of three factors on self defocusing technique used to measure the nonlinear optical properties of two solutions, the first one is safranin O dissolved in ethanol (SOE), and the second one is diphenylecarbazone dissolved in chloroform (DCC). These factors are the intensity of laser, the concentration of the solution and the effect of the temperature on the solutions.After providing the necessary solution and equipment to complete the designed experiment, an appropriate model of nonlinear system was chosen to extract the diffraction rings contains the following parts : (Diode Laser, Attenuator, Mirrors, Beam Splitter, Lens, CCD Camera, Laser Power Meter and PC) In this work the maximum change and the thermo - optical coefficient for the nonlinear refractive index as well as the nonlinear refractive index were measured, for the two different solutions (SOE & DCC) including three ratios and grains for each one. The measurements were performed using diode laser at and variable intensity (0.5 - 22) and the laser beam was focused on glass cuvette which has a thickness of through a lens with a focal length of .From this work it was found that increasing the laser intensity leads to increase the number of diffraction rings, the nonlinear refractive index and the maximum change of the nonlinear refractive index, also it was found that increasing the concentration of the solutions leads to increase the nonlinear refractive index as well as increasing the maximum change of the refractive index.Also it was found that increasing the temperature of the solution at certain intensity and concentration the obtained results for the thermooptical coefficient , and the nonlinear refractive index are found to be of the order of and at 298, 303 and 308K respectively for SOE solution, and and at 298, 303 and 308K respectively for DCC solution, in which all the thermooptical coefficient and the nonlinear refractive index are deceased.

الكشف عن البخار الكيميائي بحساسية عالية المستند على مقياس التداخل لليف البلوري الفوتوني == Chemical vapor detection with high sensitivity based on Photonic crystal fiber interferometer

Author name: رواء كاظم زرزور
Supervisor name: حنان جعفر طاهر
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:
Abstract: استخدمت مقاييس تداخلات الالياف البلورية الفوتونية في العديد من تطبيقات التحسس. في هذا البحث, تم استخدام الالياف البلورية الفوتونية ذو القلب الصلب المستندة على مقياس تداخل ماخزندر, الذي يسلك حساسية عالية لمعامل الانكسار ومختلف المركبات العضوية المتطايرة، من دون الحاجة الى اي مواد قابلة للاختراق. مقياس التداخل المدمجة ,القوية ويتكون من نهاية ليف بصري بلوري ,الليف البصري البلوري مرتبط مع الليف التقليدية ذات النمط المنفرد ((SMF - 28هذا الارتباط يكون باقل خسارة dB(0.19) في منطقة الارتباط فتحات فراغات الليف تنهار كليا, وتسمح بلتهيج واعادة التركيب للانماط القلب والغلاف .وفي منطقة الارتباط الانماط الاساسية لليف البصري التقليدي تبدا بالحيود عندما تدخل الجزء المنهار من منطقة الارتباط لليف البلوري الفوتوني . بسبب الحيود ، يوسع النمط ويسمح لاثارة نمطين رئيسيين في نهاية اليف البصري الفوتوني.الجهاز يعكس الطيف ويظهر نمط تداخل كدالة جيبية التي تظهر ازاحة بالطيف البصري بشكل مختلف عندما تتسل جزيئات المركبات العظوية المتطايرة الى فتحات الليف البصري البلوري. استخدم ليزر دايود كمصدر ضوئي وبطول موجي 1550 nm ، حيث تم استخدام محلل الطيف الضوئي (OSA) الحساس للغاية في رصد وتسجيل الطيف المنعكس. استخدم ثلاثة انواع من السوائل الكيميائية (N - الهكسين، الميثانول وبروبانول)، كل هذه السوائل الكيميائية وابخرتها لها شفافية عالية في منطقة الطيف المرئي والمنطقة تحت الحمراء القريبة. في هذه التجربة، وجدنا افضل زمن الاستجابة لهذا المتحسس هو من (30 - 35) ثانية لكميات قليلة جدا من هذه السوائل، كما تم دراسة تاثير طول المتحسس على قيمة الازاحة للطول الموجي ، تم اختبار خمسة اطوال مختلفة من PCF ذو القلب الصلب70,50,40,30and 20) nm). حدود الكشف في هذا الجهاز تم من خلالها تسجيل ازاحة في الطول الموجي لنسب من ابخرة مواد كيمياوية تصل لغاية (4.4) nm للبخار الهكسان عندما يكون طول رئس المتحسس (20)mm . في هذا العمل, الحد الاقصى للحساسية التي تم الحصول عليها للمركبات العضوية المتطايرة هي mol \15420 nm في بخار الهكسان .وقد تحققت بعض نتائج المحاكاة باستخدم برنامج COMSOL multiphysics ,تم استخدم هذا البرنامج لتصميم الليف البصري البلوري وايجاد توجيه دايود ليزر 1550 nm داخل الليف البصري البلوري عندما يتغير معامل الانكسار نتيجة لدخول ابخرة المركبات العضوية المتطايرة(هكسان, بروبان, وميثان) وملئها لفتحات الليف. نتائج mulyiphsics COMSOL عندما تسلل ابخرة السوائل الى فراغات الليف البلوري الفوتوني بدلا من الهواء. وعندما يتسلل بخار السائل الى PCF ذو النواة الصلبة (LMA - 10) الذي يؤدي الى تغيير في معامل الانكسار الفعال للPCF، والتي بدورها تؤثر على انتقال ليزر داخل PCF بسبب قيمة معاملات الانكسار للمركبات العضوية المتطايرة. ويظهر نتيجة لذلك ان طاقة طيف انتقال الليزر تخفضت بعد تسلل البخار مع التغير في الطول الموجي المركزي لليزر الدايود. | Photonic crystal fiber interferometers are used in many sensing applications. In this work, an in - reflection photonic crystal fiber (PCF) based on Mach - Zehnder (micro - holes collapsing) (MZ) interferometer, which exhibits high sensitivity to different volatile organic compounds (VOCs), without the needing of any permeable material. The interferometer is robust, compact, and consists of a stub photonic crystal fiber of large - mode area, photonic crystal fiber spliced to standard single mode fiber (SMF) (corning - 28), this splicing occurs with optimized splice loss 0.19 dB. In the splice regions the voids of the holey fiber are completely collapsed, which allows the excitation and recombination of core and cladding modes. The device reflection spectrum exhibits a sinusoidal interference pattern which shifts differently when the voids of the PCF are infiltrated with VOC molecules. Laser diode with wavelength 1550nm has been used as a pump light source, where a highly sensitive optical spectrum analyzer (OSA) was used to monitor and record the reflected spectra. Three types of chemical liquids used (N - Hexane, Methanol and Propanol), all of these chemical liquids and their vapor have a high transparency for visible and NIR spectrum. In this experiment, we found the best response time to this sensor is from (30 - 35) sec for very few quantities from these liquids which approximately measured in microliter, also it was studied the effect of the length of the head sensor on the volume of shift of the wave length, five different lengths of solid core PCF (LMA - 10) (70,50,40,30, and 20) mm were tested.The detection limits of our device associated with the maximum shifts of the wave length is 4.4nm for N - Hexane vapour when the length of the head sensor 20mm.In this work, the maximum sensitivity obtained of volatile organic compounds is 15420nm/mol at the vapor of N - Hexane.Some simulation results have been achieved by using the COMSOL mulyiphsics program. It used to design the photonic crystal fiber large - mode area and find the guiding of laser 1550 nm at this fiber when change the refractive index cladding of the photonic crystal fibers by filling the hole of cladding in vapor of (N - Hexane, propanol, methanol) at 1550 nm, The results of the COMSOL mulyiphsics when infiltration of the air holes for the PCF by vapor liquids instead of air, due the change value of the effective refractive indices of the VOCs, the power of the transmission spectrum of laser decreased after infiltration with change in the center wavelength of the laser diode

التوليد والسيطرة على التشويش في اتصالات التردد الراديوي - البصري == Chaos Generation and Control in RF - Optical Communications System

Author name: اسراء علي ياسين
Supervisor name: قيس عبد الستار النعيمي
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: Arabic
University location: Baghdad
First pages:
Abstract: تتناول هذه الاطروحة تنفيذ وتقصي موضوع الاتصالات الضوئية الفوضوية .ونظرا لمتطلبات السرية العالية، تستخدم الاتصالات الضوئية الفوضوية لتشفير الرسائل بين وحدات الارسال والاستقبال.ان الطريقة التي استخدمت للحث على السلوك الفوضوي هي طريقة التغذية المرتدة الضوئي - الالكتروني باستخدام جهاز من محاسن هذا المضمن هو عرض النطاق الترددي ودرجة التعقيد العالية. استند عمل النظام الى طريقة التغذية المرتدة. في هذا النظام، يكون جهاز مذبذب وحدة الارسال مسار مغلق بينما يكون جهاز الاستلام مسار مفتوح يستلم اشارة الفوضى من وحدة الارسال عبر وصلة الالياف الضوئية. تم البحث عمليا في طريقتين لتشفير الرسائل الى اشارة الفوضى. ان هاتين الطريقتين هما التعديل المشوش والتنكر المشوش. لقد بدانا من اختراع نظام الفوضى ودراسة خصائصه وتحديد عناصر السيطرة التي تؤدي الى حالات مختلفة من سلوك النظام. وهكذا تم تقصي الطريق الى الفوضى في مذبذب جهاز الارسال. ولملاحظة سلوك النظام، تم تحديد الرسم المتشعب من خلال تغيير العنصر المتحكم. ان عنصر التحكم هو القدرة البصرية الخارجة من الثنائي الليزري . وجرى بحث التسلسل الزمني وطاقة الطيف واعادة تكوين مساحة الطور. وقد تم بحث موضوع تزامن كلا الطريقتين. وتم الحصول على الرسالة المرسلة في وحدة الارسال من خلال تزامن المذبذب في وحداتي الارسال والاستقبال. وهكذا تم الحصول على الرسالة المستخرجة عند وحدة الاستلام. ان عرض النطاق الترددي لاشارة الفوضى الحاملة هو 200 ميكاهيرتز. وتكون قيمة القدرة الضوئية الخارجة من ثنائي اليزر والذي هو العامل المتحكم في نظامنا هذا في كسب الطوق المرتد في مذبذب الارسال بين (0.8 - 0.9) ملي واط. الرسالة كانت عبارة عن تردد راديوي 100 ميكا هيرتز وقدرة 0 ملي ديسبل. | In this thesis, the chaotic optical communication is implemented and investigated experimentally. Due to the high security requirements, chaotic optical communication is used to encrypt the message between the transmitter and the receiver units. The method which is used to induce chaotic behavior is electro - optical feedback loop by using a Mach - Zehnder modulator. The advantage for this modulator is a high bandwidth and high complexity. The system is a unidirectional feedback loop. In the scheme of unidirectional, the oscillator of the transmitter unit is a closed loop while the oscillator of the receiver unit is an open loop that receives the chaotic signal from the transmitter via an optical fiber link. Two setups were investigated experimentally to encrypt the message to the chaotic carrier signal. These methods are chaos modulation and chaos masking. We have started from creation the chaotic dynamics studied its properties and determined the control parameters that lead to various situations of the behavior of the system. The rout to the chaos for the transmitter oscillator has been investigated. To observe behavior of the system through changing of the control parameter, the bifurcation diagram is plotted. The control parameter is the output optical power of the laser diode. Time series and power spectrum of the time series is extracted by using Fast Fourier Transform FFT. The phase space reconstruction has been examined. The synchronization of two setups has been investigated. The sent message is extracted by the oscillators synchronization in the transmitter unit and the receiver unit. The extracted message has been obtained at the receiver unit. The bandwidth of the chaotic signal is about 200 MHz. The output optical power of the laser diode which is the variable control parameter of our setup in the feedback loop gain of the transmitter oscillator is between (0.8 - 0.9) mW.The message is a radio frequency at 100 MHz with power 0 dBm and is attenuated below this level with the noise level when modulated with the chaotic carrier.

تصنيع مواد متوافقة احيائيا للعظام التعويضية باستخدام الليزر ووسائل تقليدية == Fabrication of Biocompatible Material for Bone Implants Using Laser and Conventional Means

Author name: هدیل فیاض عباس
Supervisor name: رائد عبد الوھاب اسماعیل | ولید خلف حمودي
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Technology
Language: English
University location: Baghdad
First pages:
Abstract: The present work describes coating the titanium implants with biocompatible materials (ceramics or composites). Three techniques were implemented to materialize this work; these are : pulsed laser deposition, spray pyrolysis, and electrochemical deposition. In these techniques, the influence of deposition temperature, solution concentration, polymer and H2O2 addition, buffer layer sandwiching, and electrolytes combinations were tested. The obtained films’ properties were investigated by using Fourier Transform Infrared Spectroscopy (FTIR), Atomic Force Microscope (AFM), Optical Microscope, X - ray Diffraction (XRD), Scanning Electron Microscope (SEM), Vickers’ hardness instrument, and Simulated Body Fluid (SBF).Composite films prepared by pulsed laser deposition showed the formation of polycrystalline hydroxyapatite of low crystallinity due to the addition of polymeric shrimp crusts. These films had (80 - 90 nm) spherical grains and constitute only (20 - 25%) of the favorable range (80 - 200 nm), and good hardness (≈550 HV). Pure hydroxyapatite (ceramic) films had (11 - 15 nm) surface roughness and an average grain size of (48 - 65 nm) which represents (7 - 31%) of the favorable range. All these films were porous, have good adhesion, and uniform surface morphology. Best results of pulsed laser deposition technique were obtained at 125oC deposition temperature. Films prepared by spray pyrolysis showed porous polycrystalline A and B - type carbonated hydroxyapatite and single crystalline α - Ca3(PO4)2; of relatively low crystallinity and hardness increased with deposition temperature. Post annealing at 400oC and 800oC for film prepared at 350°C of (0.0325 M) solution concentration has raised the hardness from 222 HV to 488 HV and 1204.25 HV respectively. The films of (0.0325 M) solution concentration had (101 - 105 nm) average grain size and were (78 - 100%) of the favorable range, whereas the films of (0.0406 M) solution concentration had (92 - 96 nm) and made (74 - 100%) of the favorable range. Good bioactivity and adhesion strength were obtained from these films which were enhanced significantly after post annealing. Optimum results were obtained from films prepared at 350oC of (0.0325 M) solution concentration after post annealing. Films prepared by electrochemical deposition technique showed uniform and highly porous polycrystalline B - type carbonated hydroxyapatite and polycrystalline α - Ca3(PO4)2. These films had an average grain size of (66 - 93 nm) when prepared from ((NH4)2HPO4 and Ca(NO3)2) whereas the grain size was (87 - 118 nm) when prepared from (Na3PO4 and Ca(NO3)2) with low roughness values. They had (45 - 68%) and (64 - 87%) respectively of the useful grain size in the favorable range (80 - 200 nm). The films covering area increased after H2O2 addition. These films had poor adhesion but this slightly improved together with the roughness after a buffer layer was deposited.The composite films had low crystallinity, grain size, hardness, and poor adhesion. Films prepared at 70oC from both electrolytes combinations ((NH4)2HPO4 with Ca(NO3)2, and Na3PO4 with Ca(NO3)2) had the best surface morphology and crystallinity with an optimum hardness (≈475HV). All these films had very fast dissolution rate in Simulated Body Fluid. Spray pyrolysis deposition technique proved to be the most promising technique for biocompatible materials fabrication for bone implants requirement

فعالية المضاد البكتيري لاكاسيد المعادن النانوية المحضرة بواسطة الاستئصال بالليزر في سائل == Antibacterial Activity of Metals Oxide Nanoparticles Induced by Laser Ablation in Liquid

Author name: فرح عبد الكريم عبد الامير
Supervisor name: خولة صلاح خشان | غسان محمد سلمان
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Technology
Language: English
University location: Baghdad
First pages:
Abstract: With the increasing of bacterial resistance against antibiotics, nanoparticles studies was appeared together with growing need for substituting theseantimicrobial agents. Recently, it has been demonstrated that metal oxides nanoparticles exhibits bactericidal effect against both bacteria strains.In this research, three kinds of metal oxide nanoparticles (Nickel oxide, Copper oxide and Titanium dioxide) colloidal solutions synthesized using laser ablation of nickel, copper and titanium pellet immersed in de - ionized water. Pulsed Nd : YAG laser with 1٠٦٤ nm wavelength and different laser energies (40, 80, 120, 160 and 200 mJ) was used to irradiate the targets for various ablation times : 5 (75 pulse), 10 (150 pulse), 15 (225 pulse) and 20 min (300 pulse).The UV - Visible absorption spectrum of NiO nanoparticles exhibited broad bands whose intensity decreased continuously above ~210 nm. The UV - Visible absorption spectrum of the CuO nanoparticles solution showed absorption peak around ~275 nm and another peak with low intensity around ~645 nm. While absorption spectrum of TiO2 nanoparticles exhibited strong absorption domination on the spectrum below ~360 nm. In all three metal oxide nanoparticles, absorption intensity increased with the laser energy and ablation time due to increase nanoparticles concentrations in liquid. Fourier Transform Infrared spectroscopy characterization confirmed the formation of metal oxide nanoparticles. All three metal oxides nanoparticles gave absorption bands below ~600 cm−1 arising from inter - atomic vibrations. X - ray Diffraction pattern of nanoparticles proved the presence of (111), (200) planes which belong to NiO and ( - 111), (112) planes that assigned to CuO and (101), (112), ( - 403) planes that related to TiO2. TransmissionElectron Microscopy measurement showed NiO, CuO and TiO2 nanoparticles with nearly spherical shapes and sizes at 2 - 21 nm, 3 - 40 nm and 6 - 30 nm respectively.The antibacterial activity of nanoparticles carried out against four types of bacteria : Escherichia coli, Pseudomonas aeruginosa, and Proteus vulgaris (gramnegative bacteria), Staphylococcus aureus (gram - positive bacteria) firstly by liquid medium method. 1000 μg ml - 1 concentration was the best - used concentration of nanoparticles for inhibiting growth of both bacteria strains. Among the three tested types of nanoparticles (NiO, CuO and TiO2) at highest concentration (1000 μg ml - 1), TiO2 NPs showed the highest antibacterial activity against Escherichia coli and Pseudomonas aeruginosa. NiO NPs showed the highest antibacterial activity against Staphylococcus aureus while CuO NPs showed the highest antibacterial activity against Proteus vulgaris. Results also indicated that metal oxide nanoparticles and amoxicillin would have a synergistic effect on inhibiting of bacterial growth. Amoxicillin showed inhibitory rate about 74.8% against Escherichia coli and 76.28% against Staphylococcus aureus. In the case of NiO, CuO and TiO2 nanoparticles at concentration 1000 μg ml - 1 with Amoxicillin, antibacterial activity of Amoxicillin enhanced to about 81.5%, 90% and 81.9% against Escherichia coli and to about 86.9%, 91% and 90.7% against Staphylococcus aureus. Therefore, CuO nanoparticles and amoxicillin have the best synergic effect on inhibiting both bacteria strains. The antibacterial activity of the three metal oxides nanoparticle combined with Amoxicillin was also tested by well diffusion method against Escherichia coli and Staphylococcus aureus. In this method, CuO NPs at concentration 1000 μg ml - 1 along with Amoxicillin showed the highest inhibition zone against Escherichia coli (26.0±1.00 mm), while showed complete inhibition of bacteria against Staphylococcus aureus.

دراسة عملية تثقيب شرائح الزجاج باستخدام ليزر CO2 == Investigation Of Glass Sheets Hole Drilling Using CO2 Laser

Author name: لينا زكي يحيى محمد
Supervisor name: حسين علي جواد
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Master
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:

تكوين تركيب فضة دقيقة داخل الزجاج المسامي بليزر الفمتوثانية == Fabrication Of Micro Silver Structures Inside Porous Glass By Fs Laser

Author name: عبد الستار خضير عباس الغانمي
Supervisor name: مازن مانوئيل الياس
General topic: Laser Science
Specific topic: Laser Applications in Physics
Degree: Doctorate
University: University of Baghdad - Laser Institute For Postgraduate Studies
Language: English
University location: Baghdad
First pages:
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