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Article
CLEANING AND STERILIZATION EFFECT ON THE TORSIONAL PROPERTIES OF PROTAPER ROTARY TITANIUM COBALT (Ti-C0) ENDODONTIC INSTRUMENT
تأثير التنظيف والتعقيم على عزوم الالتواء لمادة التيتانيوم كوبالت المستخدمة في توسيع قنوات جذور الاسنان.

Author: Ibrahim H. Mukhlif ابراهيم حمد مخلف
Journal: Journal of university of Anbar for Pure science مجلة جامعة الانبار للعلوم الصرفة ISSN: ISSN: 19918941 Year: 2011 Volume: 5 Issue: 1 Pages: 37-40
Publisher: University of Anbar جامعة الانبار

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Abstract

This study was conducted to evaluate the effect of the number of cycles of cleaning using NaOCl solution of different concentration and sterilization using autoclave and dry heat oven on the torsional properties of rotary (Ti-Co) instruments. A total of forty five rotary protaper finisher instruments were divided into 3 groups: Group 1 were subjected to neither cleaning nor sterilization cycles and assigned as the control group. Group 2 and group 3 were subjected to 5 and 10 cleaning and sterilization cycles respectively, soaked within (2% and 5%) NaOCl, were sterilized with autoclave and dry heat oven. Then, all instruments were subjected to a clockwise torsional load until fracture, the torsional moment and angular deflection at fracture were calculated. The results show a significant reduction in the torsional strength after cleaning and sterilization cycles regardless the concentration of NaOCl, type and number of sterilization cycles. For the angular deflection, there was a highly significant reduction, where, the number of cycles was the most influencing factor for reduction of the angular deflection whereas, the concentration of NaOCl and the type of sterilization were show no significant influence on the angular deflection.

أجریت هذه الد ا رسة لتقییم تأثیر عدد م ا رت (دو ا رت) التنظیف باستخدام محلول القاصر بت ا ركیز مختلفة والتعقیم باستخدام جهاز التعقیمبواسطة البخار المحمي و الضغط و فرن الح ا ررة الجاف على خواص الالتواء للأدوات الدوارة المصنوعة من التیتانیوم كوبالت. تماستخدام خمسه أداة دوارة نوع (بروتیبر المتممة) وقد تم تقسیمها إلى ثلاثة مجامیع:- المجموعة الأولى :أدوات لم تعرض لأي من دو ا رت التنظیف والتعقیم وتم تحدیدها كمجموعة سیطرة.- المجموعة الثانیة والثالثة : تم تعریضهما لخمس وعشر دو ا رت ( تنظیف وتعقیم ) بالتعاقب، غم رت بمحلول القاصر بت ا ركیز ٢% و٥% بمحلول القاصر، تم تعقیمها باستخدام جهاز التعقیم بواسطة البخار المحمي و الضغط وفرن الح ا ررة الجاف. كل الأدوات تمتعریضها لأحمال التواء باتجاه عقارب الساعة حتى الكسر وقد تم احتساب قیم عزوم الالتواء والانح ا رف ال ا زوي لكل أداه بعد الكسر.أظهرت نتائج الد ا رسة تأثی ا ر ملحوظا في تقلیل قیم عزوم الالتواء بعد دو ا رت التنظیف والتعقیم بصرف النظر عن تركیز محلول القاصر ونوع التعقیم وعدد م ا رت التنظیف والتعقیم. بخصوص الانح ا رف ال ا زوي كان هناك تأثی ا ر عالیا ملحوظا في تقلیل قیم الانح ا رف ال ا زويللأدوات. حیث أن عدد م ا رت التنظیف والتعقیم كانت عاملا مؤث ا ر بینما كان تركیز محلول القاصر و نوع التعقیم ذو اثر غیر ملحوظ

Keywords

torque --- angular deflection --- Ti-Co


Article
Influence of Immersion Period on the Corrosion Behavior of Heat Treated Biomedical Alloy Ti -5Al - 2.5Fe
تأثير فترة الغمر على سلوك التأكل السبيكة الطبية Ti -5Al - 2.5Fe المعاملة حراريا

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Abstract

Heat treatment by solid solution method in the + phase region was used at 970°C for Ti-5Al-2.5Fe alloy. The specimens cooled under different cooling media [water quenched (WQ), air cooled (AC) and furnace cooled (FC)], and subsequently aged at 550°C for 4 hours. Five specimens from each treatment were immersed in simulated body fluid SBF for a period of time (3 months). The dependence of corrosion rate on compositional variation in the phases resulted from various type of cooling rates are discussed based on immersion tests. The EDXA results show the precipitation of phosphate and calcium compounds on the alloy after 3 months of immersion in blood plasma solution forming a bone-like apatite, which enhanced the alloy biocompatibility making it more suitable to use as biomedical implant.

تم استخدام السبيكة (Ti-5Al-2.5Fe) المعاملة حراريا (المحلول الصلب) والمدرفلة في طور(+) وبدرجة 970 م °وبثلاث أوساط للتبريد هي (الماء ، الهواء وداخل الفرن) ثم اجريت عملية التعتيق لمدة أربع ساعات للنماذج التي بردت بالماء والهواء وبدرجة550 م °.تم غمر خمسة نماذج من كل معاملة حرارية تم غمرها في مشبهات محاليل الجسم لمدة 3 أشهر. الدراسة اوضحت تاثير نوع التبريد للمعاملة الحرارية على سلوك التاكل للنماذج المغمورة في محول بلازما الدم. أظهرت فحوصات EDXRF ترسب الكالسيوم والفوسفور على السبيكة مكوناً طبقة شبيهة بالعظم مما يساعد في زيادة ملائمتها البايولوجية للاستخدامات الطبية.


Article
Generation of Intense 8-fs Pulses at 400 nm

Author: O. Duhhr
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2006 Volume: 2 Issue: 3-4 Pages: 15-17
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

Frequency-doubled pulses from a sub-40-fs, 1-kHz Ti:sapphire amplifier system are spectrally broadened in an argon-filled hollow waveguide. Compression of the self-phase-modulated pulses is implemented with chirped mirrors and a prism pair, yielding 8-fs, 15-mJ pulses in the violet spectral range.


Article
The influence of instrument application frequency on the apical extrusion of debris using rotary ProTaper, hand ProTaper and hybrid technique (An in vitro study)

Authors: Majida K. Al-Hashimi ماجدة الهاشمي --- Zaid K. Al-Doory زيد الدوري
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2012 Volume: 24 Issue: 4 Pages: 34-39
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Various kinds of hand-held or rotary instruments and techniques are used for mechanical preparationof the canal during root canal treatments. These instruments and techniques may push debris out of the canalswhich may induce inflammation within the periapical area; therefore, instrumentation technique that causes lessextrusion of debris is more desirable. The aim of this study was to compare the effect of instrument applicationfrequency on the amount of apically extruded debris.Materials and Methods: One hundred and twenty extracted human teeth were used in this study; all teeth wereshortened to a length of 15 mm. Each experimented root was mounted on a centrifuge tube that forced through aprecut hole in a rubber stopper of a glass vial. The roots were divided randomly into 3 groups, each group contained40 roots. Group R: prepared by rotary ProTaper, Group H: prepared by hand ProTaper, Group S: prepared by Hybridtechnique. Each group was further subdivided in to five subgroups (A, B, C, D, and E). Debris extruded from apicalforamen was collected in a centrifuge tube containing 0.5 milliliter of distilled water. Each empty centrifuge tube wasweighed before preparation by 0.0001g. sensitive weighing machine. Then at the end of canal preparation, thesecentrifuge tubes were completely dried using an incubator at 68 C° for two days and weighed again. The differencebetween the weights of tubes in two stages represented the weight of debris extruded from apical foramen duringinstrumentation.Results: No significant difference recorded for the mean weight of apically extruded debris regarding the instrumentapplication frequency within the same instrumentation technique; but there was a high significant difference for thesubgroups (A, B, C, and D) and a significant difference for subgroup E, regarding the effect of instrumentationtechniques on amount of apical extrusion of debris among tested groups.Conclusion: The hand ProTaper extruded smaller amounts of apical debris than the rotary ProTaper and largeramounts than Hybrid technique


Article
Intense Femtosecond Pulse Generation

Author: Krausz F.
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2013 Volume: 9 Issue: 2 Pages: 15-17
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

Frequency-doubled pulses from a sub-40-fs, 1-kHz Ti:sapphire amplifier system are spectrally broadened in an argon-filled hollow waveguide. Compression of the self-phase-modulated pulses is implemented with chirped mirrors and a prism pair, yielding 8-fs, 15-mJ pulses in the violet spectral range.


Article
Evaluation of corrosion behavior of bioceramics coated commercially pure titanium and Ti-6Al-4V alloy

Authors: Hanan Ali حنان علي --- Shatha Saleem شذى سليم --- Thair L. Al-Zubaydi ثائر الزبيدي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 3 Pages: 41-48
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study report the corrosion behavior of commercially pure titanium and Ti-6Al-4V alloy sampleswithout coating and with hydroxyapatite, partial stabilized zirconia and mixture of partial stabilized zirconia andhydroxyapatite coating and comparison between them through electrochemical polarization tests in 37 0 C Hank'ssolution.Materials and methods: Electrophoretic deposition technique (EPD) was used to achieve the coating from each oneof three types of the coating materials (HAP, PSZ and mixture of 50% HAP and 50%PSZ) on Cp Ti and Ti-6Al-4V alloysamples. The electrochemical corrosion test was performed when samples were exposed to Hank's solution preparedin the laboratory and the polarization potential, corrosion rate and the open circuit potential of the samples weremeasured.Results: The results indicated that the corrosion rate is significantly higher for Ti-6Al-4V than for Cp Ti .The three types ofcoating significantly reduced the corrosion rate for Cp Ti while did not for Ti-6Al-4V alloy .After coating the corrosionrate for Ti-6Al-4V remained significantly higher than the coated Cp Ti samples .The open circuit potential (OCP) forboth Cp Ti and Ti-6Al-4V samples was in the following sequence PSZ > HAP> mixture of HAP and PSZ >uncoated.Conclusions: Cp Ti showed less corrosion rate than Ti-6Al-4V alloy with and without coating .Coating significantlydecreased the corrosion rate of Cp Ti but did not for Ti-6Al-4V alloy

المقدمة: ان تحقق نجاح عملیة زراعة الاسنان سریریا لیس بسبب المتانة المیكانیكیة او الانسجام الحیوي المتمیز لمادة الزراعة وحسب بل بسبب صفات اخرى لمادة الزراعة مثلخواصالسطح وسلوك التاكل.المواد وطریقة العمل: استعمل الترسیب بالھجرة الكھربائیة للحصول على طلاء متجانس لواحد من ثلاثة انوع من طبقات الطلاء (الھایدروكسي ابیتایت ,الزركونیا المثبتة جزئیا وخلیط.(Ti-6Al-4V ) الھایدروكسي ابیتایتاوالزركونیا المثبتة جزئیا)على النماذج المكونة من التیتانیوم النقي وسبیكةاما بالنسبة لاختبارات التاكل الكھروكیمیاوي فقد تم قیاسھا للنماذج في محلول الجسم المماثل المحضر مختبریا وایضا قیاس جھد الاستقطاب ومعدل التاكل وجھد الدائرة المفتوحةعند مقارنتھا مع التیتانیوم النقي .ولقد لوحظ ان معدل التاكل قل بشكل واضح لنماذج التیتانیوم النقي Ti-6Al-4V النتائج: تشیر نتائج ھذة الدراسة الى ان ھناك معدل تاكل عالي لسبیكةبعد الطلاء أعلى من التیتانیوم النقي . Ti-6Al-4V وایضا بقي معدل التاكل لسبیكة .Ti-6Al-4V المطلیة بالطلائات الثلاث بینما ذالك لم یظھر لسبیكةTi-6Al- ثر على سلوك سبیكة θ قبل الطلاء وبعد الطلاء .الطلاء قلل معدل التاكل للتیتانیوم النقي بینما ذالك لم ی Ti-6Al-4V الاستنتاجات: معدل التاكل للتیتانیوم النقي اقل من سبیكة.4V


Article
Physical and Mechanical Properties Estimation of Ti/HAP Functionally Graded Material Using Artificial Neural Network

Authors: Jawad K. Oleiwi --- Rana A. Anaee --- Sura A. Muhsin
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 12 Part (A) Engineering Pages: 2174-2180
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This study presents the effort in applying neural network-based system identification techniques by using Back- propagation algorithm to predict somephysical mechanical properties of functionally graded and compositesamples from Ti/HAP, these samples were fabricated by powder metallurgy method at various volume fraction of hydroxyapatite and at n equal (0.8, 1, and 1.2). Because of important of advanced materials such as FGMs as alternative industrial material, it is necessary to measure the physical properties of these materials such as porosity, density, hardness, compression …etc. Therefore the ANN will be used to estimate these properties and give a good performance to the network.

Keywords

Ti/HAP --- ANN --- FGM --- Physical properties


Article
DEVELOPMENT OF MICRO-HARDNESS AND WEAR PERFORMANCES OF BIOMEDICAL TITANIUM

Author: Mohsin T. Mohammed
Journal: KUFA JOURNAL OF ENGINEERING مجلة الكوفة الهندسية ISSN: 25230018 Year: 2018 Volume: 9 Issue: 2 Pages: 131-138
Publisher: University of Kufa جامعة الكوفة

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Abstract

In the present work, the influence of thermal oxidation (TO) process on the micro-hardness and wear performances of a pure titanium (Ti) was studied. The process has been carried out at various values of temperature for determined time followed by furnace cooling to room temperature. The TO has supported the development of strong surface film on the Ti without spallation. This surface structure improved the results of micro-hardness and wear compared to untreated samples.


Article
The Effect of Addition of CeO2 Nanoparticles on the Microstructure and Mechanical Properties of Ti-Al-Mg Compact Samples

Authors: Mahdi M. Hanoon --- Akeel A. Al-Attar --- Ali M. Resen
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 11 Part (A) Engineering Pages: 1189-1195
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this research, Ti-15Al-5Mg alloy with different amount of CeO2nanoparticles was prepared by powder metallurgy method, the powders of thesematerials were mixed together by ball mill then the mixed powders werepressed under high pressure, the compacted samples were sintered in electronfurnace under argon gas. The density and porosity measured using Archimedesmethod, XRD and SEM images were used to detect phase's peaks andmicrostructure of all alloy sets. Vickers micro-hardness measured and Braziliancompressive tests, the results of these tests were drawing in charts with porosityand CeO2 nanoparticles percentage. From these results the best amount ofCeO2 is 7 vol.% which give best mechanical and physical properties, becauseof created of (Ti-CeO2)


Article
Compression and Wear Properties of Biocompatible Commercially Pure Titanium and (Titanium-Silicon) Alloys

Authors: Emad S. Al-Hassania --- Jamal J. Dawood --- Balsam M. Al-Sabe’a
Journal: Anbar Journal of Engineering Sciences مجلة الأنبار للعلوم الهندسية ISSN: 19979428 Year: 2019 Volume: 8 Issue: 1 Pages: 54-60
Publisher: University of Anbar جامعة الانبار

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Abstract

The porous Titanium is characterized by high permeability which can assure the ingrowth of bone tissues, and consequently results in a good bonding between the metallic implant and the bone. In this work, Silicon element was added to the Commercially Pure Titanium at different weight percent of (2, 4, 6, 8 and 10) to investigate its effect on the porosity percentage, mechanical properties of the resulted samples. XRD analysis stated that at (Si) content lower than (2 wt%) the alloy is single phase (α- Ti alloy), as the Silicon content increased, in addition to (αphase), (Ti5Si3) intermetallic compound developed in the alloy. Porosity measurement results showed that the porosity percentage increases with the increase in Silicon content. Wear results stated that the wear rate increases with the increase in silicon content due to the increase in porosity percentage while the hardness results stated that there is no significant effect for Ti5Si3 intermetallic compound on improving the hardness of the samples. This is attributed to its low percent and the major effect of porosity on hardness which declined the effect of Ti5Si3 by reducing the hardness of the alloy compared with the master sample. The obtained results of the (yield strength, ultimate compressive strength and Young’s modulus) were within the values that match bone’s properties. This means these materials are suitable for biomedical application

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