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Article
The Effect of Sodium Hypochlorite on Shear Bond between Composite and Porcelain Specimens

Authors: Ashraf S Qassim --- Sabah A Ismail --- Emad F Alkhalidi
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2012 Volume: 12 Issue: 2 Pages: 316-320
Publisher: Mosul University جامعة الموصل

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Abstract

Aim of Study: This in vitro study was conducted to evaluate the shear bond strength of intra oral por-celain repair system using 10% sodium hypochlorite and different acid etch. Materials and methods: Forty specimens were prepared in form of metal disks (8mm in diameter, 15mm height) and porcelain was applied according to the manufacturer instructions.The specimens randomly divided into 4 equal groups. In Group I ,II the samples were treated with 9% hydrofluoric acid for one minute. While groups III, IV were treated with 37% phosphoric acid for one minute, after washing the specimens with water and dryness, groups II, III the surfaces treated with 10%sodium hypochlorite for one minute while group I and IV leaved untreated. After that, the surfaces of all samples were washed and dried and silane coupling agent (MonoBond-S Vivadent, Liechtenstein) was applied according to the manu-facturer instructions, then bonding agent (Excite) (Vivadent, Liechtenstein) and composite (tetric N–ceram) (Vivadent, Liechtenstein) were applied according to the manufacturer instructions. All the sam-ples were stored in normal physiological saline for 7 days. Then the samples were thermocycled ma-nually between two water baths After that Shear bond strength was tested using universal testing ma-chine. Results: using ANOVA and Duncan’s multiple range tests. The result showed that there was highly significant difference between groups treated with 10%sodium hypochlorite with untreated one. There was significant difference between samples acid etched using hydrofluoric acid with those etched with phosphoric acid. Conclusions: Sodium hypochlorite and hydrofluoric acid significantly increase the shear bond strength between composite resin and porcelain fused to metal specimens


Article
Influence of Aluminum Oxide Conditioning Before Acid Etching on Tooth Surface: an Experimental Study

Author: Arkan Muslim Al Azzawi
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2016 Volume: 13 Issue: 1 Pages: 105-109
Publisher: Babylon University جامعة بابل

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Abstract

Aim of the present study, examination of enamel roughness in palatal aspect of extracted premolars by using aluminum oxide (25%, 27% and 28% µm and phosphoric acid 37%. Twenty of all samples contoured with cylindrical shape forming wax and poured with stone to form cylindrical shape and palatal surface remain fully visible and this surface cleaned and polished with plastic cup and pumice and rinsed with distal water and dried with air. Data divided to 4 group each one is 5 extracted teeth and variable assessed by picture captured before and after adding conditioning material by using camera, light microscope,analyzed by Autocad 3D max and electronic microscope with its three dimensional software. The result of this article clearly there is significant difference between groups with different conditioning materials also the pattern of enamel surface showing highly significant difference. This study approved that the palatal animal conditioned with aluminum oxide particles of 25%, 27%, and 28% µm before conditioned by acid etch result in greater scratched and introduce more regular pattern than that using of phosphoric acid only.


Article
Evaluation of Shear Bond Strength of Ceramic Repair With Resin Composite

Author: Emad F Al–Khalidi
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2007 Volume: 7 Issue: 3 Pages: S119-S123
Publisher: Mosul University جامعة الموصل

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Abstract

Aim: To evaluate the shear bond strength of intra oral porcelain repair system using different surface treatments when fracture of porcelain with complete metal exposure. Materials and Methods: forty specimens were prepared in form of metal disks (8mm in diameter, this diameter is for each specimen and 15mm height) and randomly divided into 4 equal groups. The first two groups were treated with air abrasion. The other groups leaved untouched. Groups I and III were treated with 37% phosphoric acid while in groups II and IV the surface were treated with 9% hydrofluoric acid, after that the surfaces of all samples were treated with silane coupling agent then bonding and composite were applied according to the manufacturer instructions. All the samples were stored in a normal physiological saline for 7 days. Then the samples were thermocycled after that Shear bond strength was tested using universal testing machine. Results: The result showed that there was a highly significant difference between groups treated with Al2O3 with those untreated one, the acid etch material. There was a highly significant difference between samples acid etched using hydrofluoric acid with those etched with phosphoric acid. Conclusion: Air abrasion and the hydrofluoric acid significantly increase the shear bond strength between composite resin and exposed metal of metal ceramic restoration


Article
Clinical assessment of stainless steel brackets failure rate after reduction of phosphoric acid concentration and etching time

Author: Ali R AL-KHATIB
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2001 Volume: 1 Issue: 3 Pages: S353-S362
Publisher: Mosul University جامعة الموصل

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Abstract

The purpose of this study was to evaluate clinically the effect of reduction of phosphoric acid concentration and etching time during bonding procedure of stainless steel brackets. As (240) metal mesh-backed brackets were bonded by using no-mix adhesive orthodontic composite, they were divided into (3) equal groups, each of (80) bracket (10 patients), the labial and buccal Surfaces of the first group was conditioned with (37%) phosphoric acid for (45) seconds, the second with (20%) for (10) seconds, and the third group was conditioned with (5%) for (15) seconds, all patients were received the orthodontic treatment by the same operator, the study period was (1) year of, the results indicate that the percentage of failure rate for the second and third groups did not significantly differ from the first group, this was calculated by using the Z-test of two proportions at (p<0.05). However, the evaluation of the adhesive remnant index (ARI) after bracket failure, revealed that the application of (37%) acid for (45) second resulted in higher amount residual adhesive left on the teeth The present study demonstrated that phosphoric acid concentration of (5%) for (15) seconds could be sufficient for bracket bonding on anterior or premolar teeth.


Article
Bond Strength of Aluminum Oxide Surface Treatment on Sandwich Restoration

Authors: Maha A AL-Murad --- Sawsan H Al–Jubori --- Nadia H Hasan
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2012 Volume: 12 Issue: 1 Pages: 89-95
Publisher: Mosul University جامعة الموصل

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Abstract

Aims: The aim of this study is to evaluate the effect of aluminum oxide as a surface treatment on shear bond strength of etched and non-etched GIC for sandwich restoration with different types of tooth co-lored restorations .In addition, failure type was assessed. Materials and Methods: Sixty Teflon molds (5mm diameter and 4mm height) of a chemically cured GIC were prepared. They were divided into two main groups 1st control, 2 ed air-abraded with 50μm aluminum oxide particles. Both groups were sub divided into two subgroups 1st control, 2 ed etched with 37%phosphoric acid. Bonding material was applied to the treated surface of all groups and cured. The second split of Teflon mold (3mm di-ameter and 4mm height)was placed onto the prepared specimenEach subgroups (1st control, 2 nd etched with phosphoric acid) were farther subdivided into three subgroups which entrain filled as fal-low: 1st split filled with a tg microhybrid, in 2 ed split filled with tg fine glass, and in 3 rd split filled with Ceram X. Shear bond strength was measured by using Universal Testing Machine, and mode of failure examined by a stereomicroscope. Results: Anova test showed that there was a highly significant difference for all variables except acid etching effect. Aluminum oxide surface treatment displays supe-rior shear (2.280MPa). tg micro hybrid composite and Ceram X showed highest shear bond strength. Conclusions: Phosphoric acid etching did not improve shear value of sandwich restorations, while uses of aluminum oxide surface treatment, tg micro hybrid and Ceram X filling material gave an improve-ment on it. The failures were mainly cohesive within the GIC except tg fine glass was cohesive in fill-ing material itself.


Article
Effect of Acetic Acid on Electrochemical Behavior of Sealed AA2319-T3 Al-Alloys Anodized in Phosphoric Acid Electrolytes
تأثير حامض الخليك على السلوك الكهروكيمياوي لأنودة وختم مسامات سبيكة المنيوم 2319 في محاليل حامض الفوسفوريك الأليكتروليتية

Author: Khalid H. Rashid خالد حامد رشيد
Journal: Al-Khwarizmi Engineering Journal مجلة الخوارزمي الهندسية ISSN: 18181171 23120789 Year: 2015 Volume: 11 Issue: 4 Pages: 1-7
Publisher: Baghdad University جامعة بغداد

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Abstract

The present study investigates the effect of acetic acid on corrosion behavior and its potential of hydrothermally sealed anodized AA2319-Al-alloys. Anodizing treatment was performed in stagnant phosphoric acid electrolyte with or without addition of acetic acid. Hydrothermal sealing was carried out in boiling water for each anodized specimen. The open circuit potential of the unsealed and sealed anodized samples was examined using open circuit potential measurement for the purpose of starting in scanning polarization diagrams. The potentiostatic polarization technique measurements were performed to assess corrosion behavior and sealing quality (i.e., degree of sealing) of the unsealed and sealed anodized aluminum. It was shown that the potentiostatic anodic and cathodic polarization of anodized aluminum was sensitive to degree of seal, which was more efficient in the case of anodized aluminum formed in acetic-phosphoric acid electrolyte mainly due to their higher corrosion potential and lower corrosion current, generally passes lower anodic and cathodic currents obtained at sealing exposure time 60 min. This suggests a specific role of the species on the sealed anodized aluminum surface coating, which contributes to the increasing of the performance in terms of corrosion improvement. The present study clearly validates the beneficial role of acetic acid in phosphoric acid anodizing baths for the corrosion protection of AA2319-Al-alloys.

في هذا البحث تم دراسة التأثير لحامض الخليك على سلوك وجهد التآكل لسبيكة الألمنيوم AA2319 المأنودة المختومة المسامية بأستخدام الماء المغلي. تم إجراء عملية الأنودة في المحلول الأليكتروليتي الساكن لحامض الفوسفوريك بوجود أو بدون إضافة حامض الخليك. تم إنجاز عملية الختم (غلق المسامات) بطريقة الماء المغلي لكل نموذج مأنود. تم إجراء فحص جهد الدائرة المفتوحة للنماذج المأنودة المختومة وغير المختومة المسامية بأستخدام قياس جهد الدائرة المفتوحة لغرض البدأ في مسح مخططات الأستقطاب. تم إستخدام تقنية الأستقطاب للجهد الساكن لتعيين سلوك التآكل وجودة الختم (أي درجة الختم) للألمنيوم المأنودة غير المختوم والمختوم المسامية. من النتائج تبين أن عملية الأستقطاب الأنودي والكاثودي الساكن للألمنيوم المأنود كانت حساسة وتتأثر بدرجة الختم و كانت أكثر كفاءة في حالة الألمنيوم المأنود المتكون في المحلول الأليكتروليتي لحامض الفوسفوريك-الخليك بشكل رئيس نتيجة لجهدهم التآكلي الأعلى قيمة والأقل تيار التآكل , بعامة يسمح بمرور أقل تيارات أنودية وكاثودية حصلت عند زمن تعرض ختم 60 دقيقة. هذا يقترح للدور المحدد للدقائق على أكساء سطح الألمنيوم المأنود المختوم مساميته الذي يساهم في تحسين الأداء من وجهة نظر التآكل. أثبتت الدراسة الحالية بشكل واضح الوظيفة المفيدة لحامض الخليك في أحواض الأنودة لحامض الفوسفوريك لحماية التآكل لسبيكة الألمنيوم AA2319.


Article
WORLD PHOSPHATE INDUSTRY
الصناعة الفوسفاتية في العالم

Author: Hijran Z. Toama هجران زين العابدين طعمة
Journal: Iraqi Bulletin of Geology and Mining مجلة الجيولوجيا والتعدين العراقية ISSN: 18114539 Year: 2017 Volume: SPECIAL ISSUE - Iraqi Phosphate Deposits Issue: 7 Pages: 5-23
Publisher: Ministry of Industry and Minerals وزارة الصناعة والمعادن

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Abstract

Phosphate rocks are the commercial source used as raw material for manufacturing phosphoric acid, phosphate fertilizers and certain other chemicals. Phosphate rocks can be used directly in some applications, whereas beneficiation is required to upgrade the ore to more than 29% of P2O5 when used as a raw material for the production of fertilizers, phosphoric acid and many other phosphate compounds. Phosphatic fertilizers are the most important end-product of phosphoric acid. Production of phosphoric acid is the first step in the manufacture of many phosphatic fertilizers. Phosphoric acid and phosphate compounds can be used directly in chemical industries or as a key ingredient in the production of many other chemicals required in detergents, animal feed, food, beverages, surface treatment (metal cleaning, coating), water treatment, dentistry, tooth pastes, fire extinguishers amongst many others. High purity phosphate compounds are also used in food and pharmaceutical production. Phosphorus as an element and some other phosphoric chemicals derived from phosphate rocks are used in pesticides, matches, fireworks and also in many military applications.

تعتبر الصخور الفوسفاتية المصدر الرئيسي لتصنيع حامض الفوسفوريك والأسمدة الفوسفاتية وبعض الكيمياويات الأخرى. يمكن استخدام الصخور الفوسفاتية مباشرة في بعض التطبيقات، ولكن معظم الصخور الفوسفاتية يتم تركيزها الى نسبة لاتقل عن 29% من خامس أوكسيد الفوسفور لتستخدم كمادة أولية في إنتاج الأسمدة وحامض الفوسفوريك والعديد من المركبات الفوسفاتية. الأسمدة الفوسفاتية هي المنتج النهائي الأهم لحامض الفوسفوريك، الخطوة الأساسية لتصنيع معظم الأسمدة الفوسفاتية هي إنتاج حامض الفوسفوريك. يمكن أن يستخدم حامض الفوسفوريك، والمركبات الفوسفاتية الأخرى مباشرة في الصناعات الكيميائية، كما يمكن استخدامها كعنصر أساسي أو ثانوي في عمل وتصنيع العديد من المنتجات المستخدمة في المنظفات، الأعلاف الحيوانية، الأغذية، المشروبات، المعالجة السطحية للمعادن (تنظيف المعادن والطلاء)، معالجة المياه، طب الأسنان، معاجين الأسنان، مطافىء الحريق، وغيرها من الاستخدامات. العديد من مركبات الفوسفات عالية النقاوة تدخل في إنتاج الأغذية والأدوية. من جانب آخر، يستخدم عنصر الفوسفور بالإضافة الى بعض المواد الكيميائية الفوسفورية الأخرى المشتقة من صخور الفوسفات في صنع المبيدات الحشرية، الألعاب النارية، وفي العديد من التطبيقات العسكرية.


Article
RECOVERY OF SOME TRACE ELEMENTS FROM IRAQI PHOSPHATE PRODUCTS
استخلاص بعض العناصر النزرة من منتجات الصناعة الفوسفاتية في العراق

Authors: Moayyed G. Jalhoom مؤيد كاصد جلهوم --- Khaldoun S. Al-Bassam خلدون صبحي البصام --- Abbas H. Humaidi عباس هادي حميدي
Journal: Iraqi Bulletin of Geology and Mining مجلة الجيولوجيا والتعدين العراقية ISSN: 18114539 Year: 2017 Volume: SPECIAL ISSUE - Iraqi Phosphate Deposits Issue: 7 Pages: 79-92
Publisher: Ministry of Industry and Minerals وزارة الصناعة والمعادن

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Abstract

Trials have been attempted to evaluate the recovery of some trace elements in the Iraqi phosphate rocks and phosphate fertilizers products since the nineties of the twentieth century. Leaching solid-liquid extraction was conducted for the recovery of Cd and Zn from the basic slime wastes produced in the Iraqi Al-Qaim fertilizer complex using various inorganic acids, basis and ammonium salts. Almost quantitative recovery was obtained for Cd and Zn by ammonium chloride and ammonium nitrate solutions.A method has been developed for the recovery of U, Th and other heavy elements from the acidic phosphogypsum produced as waste at Al-Qaim fertilizer complex using the concept of preferential solubility of phosphogypsum over other trace elements sulfates and phosphates in potable water. The undissolved or partially dissolved metal salts remain hanged as colloids then accumulated after 30 – 60 minutes. Most of the trace elements are expected to exist in water as sparingly or insoluble sulfates, phosphates, silicates and fluorides. Chemical analysis of the isolated phosphogypsum, after water evaporation, showed reasonable purity suitable for various industrial applications. The method has been further developed recently using pH, conductimetric and turbidometric techniques to follow the solubility of phosphogypsum as function of various parameters. Uranium, on the other hand, was recovered on industrial scale, from green phosphoric acid by liquid-liquid extraction technique and di-2-ethyl-hexyl-phosphoric acid (DEPA)-trioctylphosphene oxide (TOPO)-kerosene/ phosphoric acid solutions. The plant installed at Al-Qaim depends on mixer settlers as contactors. More than 150 tons of uranium was recovered as yellow cake, but the plant was destroyed during the 1991 war. High purity phosphoric acid was produced from green phosphoric acid on a pilot plant scale using liquid-liquid extraction technique and mixer-settler contactors. The extraction system "40% tributyl phosphate (TBP)-kerosene" was applied as the organic phase. The process revealed group removal of U, Th and other heavy metals as by-products in 20% green phosphoric acid.

تتناول هذه الورقه دراسة وتقييم إمكانية استخلاص بعض العناصر النزره المتوفره في صخور الفوسفات العراقيه ونواتج صناعة الأسمده الفوسفاتيه والتي بدأت في العراق منذ عقد التسعينات من القرن الماضي. أمكن ومن خلال تجارب مختبريه استخلاص واسترجاع الكادميوم والخارصين من مخلفات السلايم القاعديه الناتجه عن عمليات تركيز الفوسفات في مجمع القائم لإنتاج الأسمده الفوسفاتيه باستعمال حوامض غير عضويه وقواعد وأملاح الأمونيوم وتم تحقيق استرجاع شبه متكامل لهذين العنصرين باستعمال كلوريد الأمونيوم ونترات الأمونيوم. كما تم تطوير طريقه لاسترجاع اليورانيوم والثوريوم وعناصر ثقيله أخرى من مخلفات الفوسفوجبسم الحامضيه الناتجه عن إنتاج حامض الفوسفوريك بالطريقه الرطبه في المجمع أعلاه باعتماد قابلية الذوبان الانتقائي للفوسفوجبسم بالمياه العذبه بالمقارنه مع كبريتات وفوسفات العناصر الثقيله حيث تبقى المركبات غير الذائبه عالقه كمحلول غروي وتترسب بعد 30 – 60 دقيقه. بينت التحليلات الكيميائيه للرواسب المسترجعه المجففه نقاوه مناسبه للعديد من الاستعمالات الصناعيه وقد تم تطوير الطريقه باعتماد أساليب جديده. بدأ استخلاص اليورانيوم من حامض الفوسفوريك الأخضر صناعيا في مجمع القائم للأسمده الفوسفاتيه باعتماد التقنيات المتاحه عالميا (DEPA-TOPO) وأمكن خلال سنوات تشغيل وحدة التنقيه استرجاع ما يقرب من 150 طن من أوكسيد اليورانيوم (الكعكه الصفراء) غير أن هذا النشاط توقف بعد تدمير وحدة الاستخلاص خلال حرب الخليج عام 1991. أمكن إنتاج حامض الفوسفوريك عالي النقاوه من حامض الفوسفوريك الأخضر من خلال تجارب رياديه باستعمال تقنية الاستخلاص (TBP-kerosene) لإزالة العناصر الثقيله والمواد العضويه.


Article
Effect of phosphate ester addition on transverse strength and hardness of heat cured acrylic denture base material

Authors: Zahraa saad abed karkosh زهراء سعد --- Basima M.A. Hussien
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2018 Volume: 30 Issue: 2 Pages: 5-9
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: acrylic resin denture base consider a common denture base material for its acceptable cost, aesthetic and easy processing but still has disadvantages including easy of fracture and low impact strength.Material and method: The experimental group was prepared by addition of 15% phosphoric acid 2-hydroxyethyl methacrylate ester (PA2HEME) with polymethyl methacrylate monomer; the experimental groups was compared with the control one. The specimens were prepared according to ADA specification No. 12 with dimension 65 mm x 10 mm x2.5 mm (length x width x thickness respectively). The prepared specimens were tested by three-point flexural strength utilizing Instron Universal Testing Machine (WDW, Layree Technology Co.), Shore D hardness tester used to measure hardness test. Statistical analysis used student T- test, mean and standard deviation.Results: The result of PA2HEME group showed high significant reduction comparing to the control group for both transverse strength and hardness test.Conclusion: Mixing 15% of PA2HEME with 85% methyl methacrylate (MMA) can reduce the mechanical properties of new modified polymethyl methacrylate (PMMA) acrylic resin


Article
Antibacterial Inhibitor as an Expired Metoclopramide in 0.5M Phosphoric Acid
المثبط المضاد للبكتريا كميتوكلوبراميد منتهي الصلاحيه في 0.5 مولاري من حامض الفسفوريك

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Expired drug Metoclopramide was investigated as an antibacterial corrosion inhibitor for carbon steel in 0.5M H3PO4 solution using the electrochemical method at 30oC and 60oC. The results showed that this drug is an efficient inhibitor for carbon steel and the efficiency reached to 82.244 % for 175 ppm at 30oC and 76.146% for 225 ppm at 60oC. The adsorption of drug on carbon steel surface follows Langmuir adsorption isotherm with small values of adsorption-desorption constant. The polarization plots revealed that Metoclopramide acts as mixed-type inhibitor. Some parameters of inhibition process were calculated and discussed. The surface morphology of the carbon steel specimens was analyzed using scanning electron microscope and energy dispersive X-ray analysis. Antibacterial activity of inhibitor was also tested. Fourier-transform infrared (FTIR) spectroscopy confirmed the inhibitive role of Metoclopramide drug.

الدواء المنتهي الصلاحيه ميتوكلوبراميد تم اختباره كمثبط التأكل المضاد للبكتريا للفولاذ كاربوني في محلول 0.5 مولاري من حامض فسفوريك بأستخدام الطريقة الكهروكيميائية في 30 و 60 درجة مئوية. وأظهرت النتائج أن هذا الدواء هو مثبط فعال للفولاذ كاربوني والكفاءة وصلت إلى 82.244 % لل 175 جزء من مليون عند 30 درجه مئويه و76.146 % لل 225 جزء من مليون عند 60 درجه مئويه. امتزاز الدواء على السطح فولاذ كاربوني يتبع متساوي الحراره الامتزاز مع القيم الصغيره لثابت امتصاص الامتزاز. كشفت سير الاحداث في الاستقطاب ان ميتوكلوبراميد يعمل كمثبط من نوع المختلط . بعض معامل عمليه التثبط تم حسابها ومناقشتها. التشكل السطحي للعينات فولاذ كاربوني تم تحليلها بأستخدام المجهر المسح الألكتروني و تحليل الأشعة السينية المشتتة للطاقة. تم اختبار المثبط الفعال المضاد للبكتريا. أكد التحليل الطيفي دور المثبط للدواء ميتوكلوبراميد.

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