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Article
The effect of TiO2 addition on the thermal conductivity of Polymethylmetha acrylate, Polycarbonate and Polystyrene Polymers
تأثير اضافة اوكسيد التيتانيوم على التوصيلية الحرارية لبوليمرات البولي مثيل ميثا اكريليت, البولي كاربونيت و البولي ستايرين

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Abstract

Thermal conductivity measurement was done for specimens of Polystyrene/ titanium dioxide, Polycarbonate/ titanium dioxide and Polymethylmetha acrylate/ titanium dioxide composites for weight ratio of 1.9/ 0.1 and 1.8/ 0.2 wt% for different thickness of the samples. The experimental results show that the thermal conductivity is increased with the increasing of thickness of layers and with the weight ratio of TiO2.

تم في هذا البحث دراسة التوصيلية الحراراية لعينات من متراكبات البولي ستايرين / ثاني اوكسيد التيتانيوم, البولي كاربونيت / ثاني اوكسيد التيتانيوم و البولي مثيل ميثا اكريليت / ثاني اوكسيد التيتانيوم وبنسب وزنية 0.1/1.9و 0.2/1.8من ثاني اوكسيد التيتانيوم .تشير النتائج الى ان التوصيلية الحرارية تزداد بزيادة كل من سمك طبقة المتراكب ونسبة تركيز ثاني اوكسيد التيتانيوم .


Article
Structural and Optical Properties of Annealed TiO2 Powder Synthesized by Hydrothermal Method
الخصائص الهيكلية والبصرية من مسحوق ثاني أكسيد التيتانيوم النانوي توليفها بواسطة طريقة الحرارية المائية

Authors: Sariya D. Al-Algawi ساريه العلكاوي --- Rashed T. Rasheed راشد رشيد --- Zeena R. Rhoomi زينة رباح رحومي
Journal: Iraqi Journal of Science المجلة العراقية للعلوم ISSN: 00672904/23121637 Year: 2017 Volume: 58 Issue: 3C Pages: 1683-1693
Publisher: Baghdad University جامعة بغداد

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Abstract

Titanium dioxide (TiO2) Nano powder has been synthesized by hydrothermal method. The reaction took place between titanium tetrachloride (TiCI4) and mixture solution consisted of deionized water and ethanol, in the ratio (3:7) respectively. Structure and surface morphology of TiO2 Nano powder at different annealing temperatures in the range 200-800°C for 120 min were characterized by X-ray diffraction (XRD), Atomic Force Microscope (AFM), Scanning Electron Microscopy (SEM), FT-IR and UV/visible spectroscopy measurements. The results show that with an increase in annealing temperature, the value of the intensity of (110) peak for rutile phase increases while the value of the full-width at half maximum (FWHM) decreases, and the band gap decreases with increasing temperature.

حضر اوكسيد التيتانيوم بتقنية الحراره المائيه في الأوتكليف، حصل التفاعل بين رباعي كلوريد التيتانيوم ومزيج متكون من ماء لاايوني وايثانول بنسبة (37:) بالتتابع. تركيب وطبغرافية السطح لاوكسيد التيتانيوم النانوي الملدن بدرجات حرارية مختلفة (200-800) ͦ م لمدة 120 دقيقة تم تشخيصها بواسطة قياسات حيود الاشعة السينية (XRD)، مجهر القوة الذرية (AFM)، المجهر الألكتروني الماسح (SEM) ومطيافية الأشعة تحت الحمراء (FT-IR) والأشعة فوق البنفسجية/المرئية (UV/Visible). اظهرت النتائج ان شدة القمة (110) لطور روتايل تزداد بزيادة درجة حرارة التلدين بينما العرض عند منتصف الارتفاع (FWHM) يقل وان فجوة الطاقة تقل مع زيادة درجة حرارة التلدين.


Article
Evaluation the Castability of Titanium Casting Alloy

Authors: Lamia T Rejab --- Ibtehal H Hasan --- Salwan F Al-Hamdani
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2013 Volume: 13 Issue: 23 Pages: 396-402
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: is to evaluate the castability of titanium alloy and compare it with that of nickel-chromium and cobalt-chromium alloys by measuring castability and porosity values. Materials and methods: A total of 30 samples were prepared for castability and porosity tests. Castability was measured by castability test according to Hinman method by measuring the numerical number of the reproduced segments of casting samples . Porosity value was measured by determined the porosity percentage according to (Archimedes) method . ANOVA and Duncun,s multiple range test were carried out to determine the significant difference at p ≤ 0.05% . Results: the results showed that titanium alloy has a lowest value of castability and the highest value of porosity percentage, While cobalt-chromium alloys has intermediate values. Nickel-chromium alloy has highest value of castability and the lowest value of porosity. Conclusion: there is a significant differences between the castabilty and porosity values among different casting alloys used. The differences between the catability values are related to variance between the melting temperature of the different casting alloys, the higher the melting temperature the less castability value.

Keywords

Castability --- Titanium --- porosity


Article
Comparison Study for the Quantity of Titanium Exist in Different Type of Dental Implant Alloy

Author: Jameel MA Sulaiman
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2013 Volume: 13 Issue: 23 Pages: 560-565
Publisher: Mosul University جامعة الموصل

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Abstract

The current study aims to compare alloys of dental implants and to find the ratio of titanium element (Ti) with different origins which are used by dentists in dental implant to restore the missing teeth. Materials and Methods: Three types of dental implants from Germany, Italy and Korea used in this study for statement the chemical structure of these alloys using (XRD: X-Ray Diffraction) (Model S1TurboSD LECE, BRUKER). Hardness, tensile strength, and flexibility coefficient tested by hardness measuring device Micro Hardness – AMSLER, Germany, 1978. The microstructure of samples obtained by Metrology Microscope (600X), ME-3125, UNION, 1978, Japan. Results: Different elements appeared in each alloy, and the titanium (Ti) ratio was the main one, where the Germany type (95.14%), Italy, (91.21%), while Korea type was the highest (95.21%). Tension Resistance in Germany model (755) N/(mm)2, Italian (781) N/(mm)2, and Germany (785) N/(mm)2. Hardness Vickers (HV) in Germany (277), Italy (285) and for Korean type (287). Modulus of elasticity, in Germany (107) Gpa, in Italy (115) Gpa. and in Korean (107) Gpa. The classification according to the American Society for Testing and Materials found in Germany Ti 3-2.5, Italy Ti6-2-1-1, and in Korean Ti 3-2.5. Conclusions: The Korean sample is best for three reasons the quantity of Titanium, Hardness Vickers (VH) and Tension Resistance are more. The Italy type is found better for Modulus Elasticity, while the Germany type is better in Microstructure. In general, and since, the three types have more than (90%) of Titanium there for all the types of dental implant are good against corrosion from acid and Hydrofluoric (HF).

Keywords

Dental Implant --- Titanium --- Alloy


Article
Corrosion Behavior of Ti-6Al-4V Alloy in Different Media
سلوك التأكل لسبيكة Ti-6Al-4V في اوساط مختلفة

Authors: Slafa I. Ibrahim سلافه إسماعيل إبراهيم --- Majid H. Abdulmageed ماجد حميد عبد المجيد
Journal: Al-Khwarizmi Engineering Journal مجلة الخوارزمي الهندسية ISSN: 18181171 23120789 Year: 2010 Volume: 6 Issue: 3 Pages: 77-84
Publisher: Baghdad University جامعة بغداد

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Abstract

In this work the corrosion behavior of Ti-6Al-4V alloy was studied by using galvanostatic measurements at room temperature in different media which includ sodium chloride (food salt), sodium tartrate (presence in jellies, margarine, and sausage casings,etc.), sodium oxalate (presence in fruits, vegetables,etc.), acetic acid (presence in vinegar), phosphoric acid (presence in drink), sodium carbonate (presence in 7up drink,etc.), and sodium hydroxide in order to compare.
Corrosion parameters were interpreted in these media which involve corrosion potential( Ecorr) and corrosion current density (icorr), since the results of (Ecorr) indicate that Oxalate ions are more corrosive than other materials while the results of (icorr) indicate that NaCl is more corrosive than other materials. Cathodic and Anodic Tafel slopes that were used to calculate the polarization resistance (Rp) to know which materials effect on Ti-6Al-4V alloy uses in dental materials and the results of (Rp) were: Na2CO3 >Oxalate >H3PO4 >CH3COOH >NaOH >Tartrate >NaCl.
The change in free energy (&#8710;G) and rate of corrosion in (mpy) were calculated, and the results of rate indicate that increasing in the following sequences: NaCl>Tartrate >NaOH >Oxalate> CH3COOH> H3PO4> Na2CO3.

في هذا البحث تم دراسة سلوك التآكل لسبيكة (Ti-6Al-4V) باستخدام القياسات الكلفانية الساكنة في درجة حرارة الغرفة وفي اوساط مختلفة تضمنت كلوريد الصوديوم (ملح الطعام) وترترات الصوديوم (المستخدم في الهلام، الزبد النباتي، وأغلفة السجقِ، الخ. ) واوكزالات الصوديوم (الموجود في الفواكه و الخضروات ،الخ.) وحامض الخليك (الموجود في الخل) وحامض الفسفوريك (الموجود في مشروب الببسي) وكاربونات الصوديوم (الموجودة في مشروب السفن اب) وهيدروكسيد الصوديوم لغرض المقارنة. تم تفسير متغيرات التآكل المحسوبة لهذه الأوساط والتي تتضمن جهد التآكل وكثافة تيار التآكل، حيث بينت نتائج جهد التاكل ان مادة الاوكسالات هي الاكثر تأكلاً في حين اظهرت نتائج كثافة تيار التاكل بان كلوريد الصوديوم هو الاكثر تأكلاً من بقية المواد. تم استخدام نتائج ميول تافل الكاثودية والانودية لحساب مقاومة الاستقطاب لمعرفة المواد الاكثر تأثيراً على سبيكة Ti-6Al-4V المستخدمة في مجال طب الاسنان وكانت النتائج كما يلي: Na2CO3 >Oxalate >H3PO4 >CH3COOH >NaOH >Tartrate >NaClكما تم حساب التغير في الطاقة الحره وسرعة التآكل في الاوساط المختلفة. بينت نتائج حساب معدل سرعة التآكل بوحدة (مل لكل سنة) بأنها تأخذ التسلسل التالي: >Na2CO3


Article
Effect of Artificial Salvia on Force Values of Two Types of Nickel Titanium Ortho-dontic Arch Wires

Authors: Afrah K Al -Hamadani --- Enas T Al-Jwary
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2012 Volume: 12 Issue: 20 Pages: 301-308
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: To study the effect of artificial saliva and time interval on the amount of force values of nitinol and superelastic NiTi wires. Materials and Methods: Two types of orthodontic wires chosen for the study nitinol and superelastic NiTi wires of a guage of 0.016 inch in diameter (Dentaurum, Germany). Specimens of the wires were divided in to two groups ;the control group(dry condition) contained the wires as - received condition and experimental groups for the study of the force value of wires which subjected to artificial saliva for three time incubation periods (3 days, 7 days, 28 days) . At end of each incubation periods ,the wire specimens were tested for the effect of artificial saliva on force values of the wire. The measurement of force values of arch wires done with a universal tensile testing ma-chine ,the force values of specimens were evaluated with the help of three point bending test. The re-sults were subjected to the descriptive statistics and to the ANOVA and Duncan’s Multiple Range Analysis Tests to detect the amount of changes among these groups . Result: The findings of the present study showed that the control group of nitinol wires had the highest rate of force value with significant difference (P≤ 0.05) with experimental groups, while the experimental group after 28 days gave rise to the lowest one with significant difference (P≤ 0.05) from other groups. For the superelastic nickel titanium the result showed that the control group had the highest rate of force value while the experimental group after 28 days gave rise to the lowest one with significant difference (P≤ 0.05) from control and non significant difference (P> 0.05) with the experimental groups after 3 days and 7 days. Conclusion: The nitinol wires showed a continuous change in force values with increase time in ar-tificial saliva, so this required reactivating or changing the wire at a certain interval of use. While force values of the superelastic nickel titanium wires decreased after 3 days interval and remained constant after that .


Article
Laser Energy Effects on Optical Properties of Titanium Di- Oxide Prepared by Reactive Pulsed Laser Deposition
تاثیر طاقة اللیزر على الخصائص البصریة لاغشیة اوكسید التیتانیوم المحضرة باستخدام تقنیة الترسیب باللیزر النبضي

Authors: Mukkaram. A Fakhry --- Farah A. Hattab --- Esraa K. Hamed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2012 Volume: 30 Issue: 17 Pages: 3104-3111
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this Work, Laser energy effects on optical and morphological properties ofTiO2 thin film has been carried out using Reactive Pulsed Laser as a Depositiontechnique (RPLD). Q-switched Nd-YAG laser with (ë=1.06ìm, t =7nsec) anddifferent energies have been used to ablate pure Titanium target and deposited thinfilms on glass substrates with constant substrate temperature of (343K). The opticalproperties of the films prepared include Optical transmit ion and absorptionmeasurement, surface uniformity measurement and FTIR structure of these films.The results films show that high transparency reached to about (85-98) % can beachieved with TiO2 film which itself decreases sharply with the increasing of Laserenergy while the optical band gap is (3.7-3.9) eV at optimum Laser energy in allresults (800mJ), the FTIRstructure result at 800 mJ is the optimum and peaksabsorption of TiO2 are (408.91, 439.77, 524.64) cm-1.

في ھذا العمل، تم دراسة تأثیرطاقةاللیزرعلﯨالخصائص البصریة والشكلیة لاغشیةثاني أكسیدحیث تم .(RPLD) الرقیقةالمنماة باستخدام تقنیة الترسیب باللیزر النبضي , TiO التیتانیوم 2الذي یعمل بتقنیة عامل النوعیة ذو طول موجي Nd-YAG استخدام لیزر الندیمیوم–یاك النبضيعند طاقات ةفلتخم لتشظیة اھداف معدن التیتانیوم (t=7nsec) و امد نبضة (λ=1.06nm)343 ).ان الخصائص البصریة للاغشیة المنماة K) وترسیبھ على قواعد زجاجیة عند درجة حرارةتشمل حساب الامتصاصیة و النفاذیة و معرفة مدى انتظامیة السطح و كذلك الخصائص التركیبیةللمادة حیث اظھرت نتائج الخصائص البصریة لاغشیة اوكسید التیتانیوم ان نسبة النفاذیة عالیة و 310585 ) وانھا تقل بحدة مع زیادة طاقة اللیزر. كما و ان فجوة الطاقة البصریة - تتراوح ما بین% ( 98800 ). اما mJ) 3.7-3.9 ) و ان افضل النتائج كانت عندما طاقةاللیزر تساوي )eV تتراوح ما بینتبین ایضا اعلى قمة امتصاص لاوكسید التیتانیوم (FTIR) نتائج الخصائص التركیبیة للاغشیة.800 mJ عند طاقة لیزر تساو


Article
Histological evaluation of osseointegration around titanium implants in thyroidectomized rabbits (experimental study).

Authors: Zaid M. Ali زيد علي --- Nada M. H. Al-Ghaban ندى الغبان
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: 2 Pages: 75-79
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Thyroid hormones are essential for linear growth and peak bone mass acquisition. Hypothyroidismoccurs when the thyroid gland produces less than the normal amount of thyroid hormones. The present study wascarried out to evaluate the effect of hypothyroidism on osseointegration around the titanium implants screwed inrabbit's tibia.Materials and methods :Fifty four machined surface Iraqi implants were inserted in 27 male rabbits (2implants in eachrabbit's tibia ).Eighteen of these rabbits were subjected to near total thyroidectomy to induce hypothyroidism threeweeks before implantation surgery. While the remaining 9 rabbits were remain as a control group. Blood sample wastaken from each animal at the beginning of this study in order to find the normal range of T3,T4,and TSH .And anotherblood sample was taken for experimental groups to find the levels of T3,T4,and TSH three weeks after thyroidectomyin order to assess the hypothyroidism status .After 2, 4, 6 weeks after implant surgery (6rabbits from experimentalgroup and 3rabbits from the control group) were sacrificed. In the day of scarification, one of the screws wasunscrewed with a torque meter, and the peak torque required to shear off the implant was recorded. Then thedecalcified sections of the bone around the implants were studied histologically and histomorphometrically .The eyepiece reticule was used for morphometrical studies, which were includes: number of osteocytes, number ofosteoblasts, thickness and number of bone trabeculae, and thread widthResults:The results showed that hypothyroid rabbits had delay in osseointegration, bone formation and maturationaround implants in almost all rabbits in experimental groups. While the rabbits in the control groups showedimprovement in osseointegration around titanium implant. Removal torque test illustrated higher torque test value incontrol animals than in experimental one. Moreover, there were increases in torque test values in both groups withtime. Biochemical serum analysis revealed a decrease in T3, T4, and increase TSH levels in experimental animals.Conclusion: It can be concluded that there were low bone quality with a delay in bone healing around titaniumimplants in hypothyroidied rabbits compared with healthy one.


Article
Phthalanilinc Acid Complexes of Titanium (IV) and Zirconium (IV)

Authors: Wijdan A. Al-Zeadan --- Roaa Haddad
Journal: Tikrit Journal of Pure Science مجلة تكريت للعلوم الصرفة ISSN: 18131662 Year: 2012 Volume: 17 Issue: 4 Pages: 67-71
Publisher: Tikrit University جامعة تكريت

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Abstract

In this paper we report the synthesis of a number of titanium (IV) and zirconium (IV) complexes of the formulas [Ti(LH2)Cl2]Cl2 ,[Zr(LH2)2](NO3)4 , [ZrO(LH2)]Cl2, [Ti(L)Cl2] ,[Zr(L)2] , [Zr(OH)2(L)], by the reaction of the phthalanilic acid ligand, furfuroylhydrazido-ortho-acetobenzoic acid (LH2, scheme 1), with titanium tetrachloride, zirconium nitrate or zirconyl chloride. The ligand prepared by the reaction of furfuroylhydrazide with phthalic anhydride. Reactions of this ligand with the metal salts in both neutral and basic solutions gave cationic and neutral complexes, respectively. The prepared ligand and its complexes were characterized by elemental analysis, molar conductance and by infrared and ultraviolet spectra. In all complexes the ligand acts as neutral tetradentate in neutral medium and dibasic tetradentate in basic medium. Titanium complexes are hexacoordinated with octahedral structure, while zirconium complexes have different structures. Zirconium nitrate complexes are octacoordinated with the most probable square antiprism geometry. On the other hand, the two complexes of zirconyl chloride obtained from neutral and basic media are penta- and hexa-coordinated with the most common square pyramidal and octahedral structures, respectively.

تضمن هذا البحث تحضير عدد من معقدات التيتانيوم والزركونيوم مع الليكاند من نوع حامض الفثالانيليك، فورفورايل هيدرازيدو-أورثو-أسيتو حامض بنزويك (LH2، المخطط رقم 1)، وذلك بتفاعل رباعي نترات الزركونيوم وكلوريد الزركونيل مع الليكاند المذكور. تم الحصول على الليكاند من تفاعل هيدرازيد الفورفوريل مع أنهدريد الفثالانيليك. وحضرت المعقدات في كل من الوسطين المتعادل والقاعدي، إذ نتج عن الوسط المتعادل معقدات أيونية موجبة ذات الصيغ، [Ti(LH2)Cl2]Cl2 و [Zr(LH2)2](NO3)4 و [ZrO(LH2)]Cl2، في حين أعطى الوسط القاعدي معقدات متعادلة لها الصيغ، [Ti(L)Cl2] و [Zr(L)2] و [Zr(OH)2(L)]. وتم تشخيص الليكاند ومعقداته بالتحليل الدقيق للعناصر وقياسات التوصيل الكهربائي وأطياف الأشعة تحت الحمراء وفوق البنفسجية.وقد دلت التحاليل على أن الليكاند يسلك بشكل رباعي السن متعادل في الوسط المتعادل ورباعي السن ثنائي القاعدة في الوسط القاعدي. واتضح أن أيون التيتانيوم في هذه المعقدات يتخذ التناسق السداسي ذو بنية ثماني السطوح، ويأخذ أيون الزركونيوم التناسق الثماني ذو بنية معكوس الموشور المربع، الأكثر احتمالاً. من ناحية اخرى، اتضح أن لمعقد كلوريد الزركونيل الناتج عن الوسط المتعادل التناسق الخماسي ذو بنية الهرم المربع الأكثر شيوعاً. في حين أظهر معقد كلوريد الزركونيل الناتج عن الوسط القاعدي التناسق السداسي ذو بنية ثماني السطوح الشائعة.


Article
Photocatalytic Degradation of Cobalamin by Metalized TiO2

Authors: Ahmed F. Halbus --- Falah H. Hussein
Journal: Journal of University of Babylon مجلة جامعة بابل ISSN: 19920652 23128135 Year: 2012 Volume: 22 Issue: 1 Pages: 445-453
Publisher: Babylon University جامعة بابل

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Abstract

The purpose of this study was to investigate experimentally the degradation of cobalamin by suspensions of platinum and other metals supported on Hombikat UV100 . The effect of temperature on the efficiency of photodegradation of cobalamin was studied in the range 278-298K using UVA source of irradiation. The activation energy was calculated according to Arrhenius plot, and was found equal to 22 ±1 kJ.mol-1 for TiO2. The results showed that pH of reactants was changed at the end of reaction towards 7 independent on the initial pH .The results of the total organic carbon (TOC) analysis indicate that the rate of degradation of dye was faster than the total mineralization. Decolorization and mineralization of cobalamin in the absence of light and/or catalyst were performed to demonstrate that the presence of light and catalyst is essential for the degradation of this cobalamin. The results show that the activity of different types of metals used in this study was in the following the sequence:Pt/TiO2 > Pd/TiO2 > Au/TiO2

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