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Article
Salivary alkaline phosphatase and acid phosphatase levels in gingivitis diagnosis and treatment
مستويات الفوسفاتيز القلوية اللعابية وحمض الفوسفاتيز الحمضي في تشخيص وعلاج التهاب اللثة

Authors: Bakhtiar Mohiadeen Ahmed --- Sherzad Abdul-Rahman
Journal: Zanco Journal of Medical Sciences مجلة زانكو للعلوم الطبية ISSN: 19955588/19955596 Year: 2014 Volume: 18 Issue: 2 Pages: 726-731
Publisher: Hawler Medical Univeristy جامعة هولير الطبية

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Abstract

Background and objective: Gingivitis is the presence of clinical signs of inflammation in gingiva and is associated with teeth showing no attachment loss. Human saliva contains informative components that can be used as diagnostic markers for human diseases. This study is directed to evaluate salivary phosphatase enzymes levels in diagnosis and follow up the treatment of gingivitis.Methods: Saliva samples were collected from 100 healthy persons, and 50 patients before treatment (scaling and polishing) and 20 days after the treatment. Their age ranged between 20-30 years. Alkaline phosphatase and acid phosphatase activities, some kinetics and thermodynamic parameters were measured.Results: Salivary alkaline phosphatase and acid phosphatase activities elevated in gingivitis, while their levels returned to the control values after treatment. The Michaelis constant (Km) values for salivary alkaline phosphatase and acid phosphatase decreased in gingivitis, while the maximum velocity (Vmax) values increased. These values returned back to normal values after treatment. The changes in the thermodynamic parameters (∆H*, ∆G* and ∆S*) values of transition state for salivary alkaline phosphatase were non-significant, while their changes were significant for salivary acid phosphatase, except for ∆G* value.Conclusion: Salivary alkaline phosphatase and acid phosphatase levels can be relevant for diagnosis and the follow-up of gingivitis treatment.


Article
Corrosion and Corrosion Inhibition of -Brass by Thiourea
تآكل وتثبيط تآكل سبيكة الفا- براص بواسطة الثايويوريا

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Abstract

The corrosion behavior and corrosion inhibition of -brass (65.3% Cu, 34.4% Zn and others 0.3%) in 0.6 mol.dm-3NaCl solution have been investigated using potentiostatic polarization technique, the main results obtained were expressed in terms of corrosion (Ec) and corrosion current(ic).The research was performed in neutral and slightly acidic media [pH=7 and pH=4] over the temperature range (288-318)K. It was found that the rate of corrosion increases with the increase of acidity and the increase of temperature. The rate of corrosion increased with the increase of temperature in conformity with Arrhenius equation. Values of activation energy (Ea*), pre-exponential factor (A) and entropy of activation (S*) have been derived for the corrosion process. Also the thermodynamic quantities (G, S and H) have been determined for the process. The inhibition effect of thiourea on the corrosion of -brass in chloride solution was studied, and it was found that the addition of thiourea to the chloride solution caused a decrease in the values of corrosion current density and changed to some extent the values of kinetic parameters. The values of (Ea) increases in the presence of thiourea, this means that the decrease of the concentration of thiourea.

يتناول موضوع البحث دراسة كهروكيميائية لتأكل وتثبيط تاكل سبيكة الفا براص (-brass)Cu 65.3% ، Zn 34.4% في محلول ملحي لكلوريد الصوديوم بتركيز 0,6 مول. دسم-3 باستعمال تقنية المجهاد الساكن، وتم التعبير عن النتائج من خلال تسجيل قيم جهد التآكل (ic) . درس سلوك التآكل في الوسط المتعادل والقليل الحامضية pH 4 و7 وعلى مدى من درجات الحرارة من 288 الى 318 كلفن. لوحظ ان سرعة التآكل تزداد بزيادة الحامضية وزيادة درجة الحرارة، اذ خضعت حركية تفاعل التآكل لمعادلة ارينيوس التي من خلالها حسبت قيم طاقة التنشيط (Ea*) ومسبوق المقدار الاسي (A) وانثروبي التنشيط (S*) كما امكن حساب الكميات الثرموديناميكية لتفاعل التآكل (G, S, H) كما اشتمل البحث على دراسة استعمال مادة الثايويوريا مثبطاً لعملية تآكل سبيكة الفا براص في محلول كلوريد الصوديوم بالتركيز المشار اليه اعلاه، واتضح ان اضافة الثايويوريا عملت على تقليل سرعة التآكل من خلال قيم تيار التآكل المتناقصة، ولوحظ زيادة قيم طاقات التنشيط عند اضافة الثايويوريا وهذا يعني ازدياد الحاضر الطاقي لعملية التآكل وكانت هذه الزيادة في علاقة عكسية مع تركيز الثايويوريا.

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