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Article
Synthesis and characterization of Mercury (II) complexes of N-Phenyl-N-(2-Pyridyl or 2-benzothiazole) thiourea.
تحضير وتشخيص معقدات الزئبق (II) مع N-Phenyl-N-(2-Pyridyl or 2-benzothiazole) thiourea.

Author: Adnan A. N. Al- Dulaimi عدنان عبد النبي حمادة الدليمي
Journal: Tikrit Journal of Pure Science مجلة تكريت للعلوم الصرفة ISSN: 18131662 Year: 2010 Volume: 15 Issue: 1 Pages: 226-230
Publisher: Tikrit University جامعة تكريت

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Abstract

Mercury(II) complexes of the type [HgX2(LH)] {X= Cl, Br, I, or SCN; LH= N-Phenyl-N-(2-pyridyl)thiourea or N-Phenyl-N-(2-benzothiazole)thiourea were prepared and characterized by elemental analysis and infrared spectra. The complexes were highly insoluble in common organic solvents to be characterize by NMR or conductivity measurements.

تم تحضير وتشخيص معقدات الزئبق (II) من نوع HgX2(LH)] {X= Cl, Br, I, or SCN; LH= N-Phenyl-N-(2-pyridyl)thiourea or N-Phenyl-N-(2-benzothiazole)thiourea .بواسطة التحليل الدقيق للعناصر ومطيافية الاشعة تحت الحمراء. المعقدات عديمة الذوبان بصورة كبيرة في معظم المذيبات العضوية الشائعة لذلك لم يتم التمكن من اجراء قياس التوصيلية الكهربائية وطيف الرنين المغناطيسي (NMR) لهذه المعقدات.


Article
Effects of Prenatal metallic mercury vapor exposure on the developing teeth of rats

Author: Ghada M. Mustafa B.D.S . M.Sc.* د. غادة مصطفى
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2006 Volume: 3 Issue: 2 Pages: 197-201
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

This Study represents an attempt to investigate histologically the effect of metallicmercury vapor on the developing rat teeth after inhalation by pregnant rats .In this study albino – wistar rats were used and divided into control andexperimental groups.The control group consisted of 8 pregnant rats, and the experimental groupconsisted of 12 pregnant rats. Then 20 born rats from the control group and 20 bornrats from the experimental group were selected to be sacrificed at the ages of (3&13)days.The specimens were prepared for processing and staining with haematoxylin andeosin, and examined under light microscope.Results showed no histological abnormalities in the dental tissue of theexperimental group when compared to that of the control group .This Study represents an attempt to investigate histologically the effect of metallicmercury vapor on the developing rat teeth after inhalation by pregnant rats .In this study albino – wistar rats were used and divided into control andexperimental groups.The control group consisted of 8 pregnant rats, and the experimental groupconsisted of 12 pregnant rats. Then 20 born rats from the control group and 20 bornrats from the experimental group were selected to be sacrificed at the ages of (3&13)days.The specimens were prepared for processing and staining with haematoxylin andeosin, and examined under light microscope.Results showed no histological abnormalities in the dental tissue of theexperimental group when compared to that of the control group .


Article
A comparative study between the atomic absorption and spectrophotometric method in the assessment of the corrosion

Author: Suhad.J.Hemed
Journal: journal of kerbala university مجلة جامعة كربلاء ISSN: 18130410 Year: 2011 Volume: 9 Issue: 4 Pages: 21-25
Publisher: Kerbala University جامعة كربلاء

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Abstract

Back ground: Atomic absorption method is the most accurate method in the assessment for the determination of corrosion of dental alloy. The spectrophotometric method with the use of chromogenic complex was used also in the assessment of the corrosion. The aim of this study was to compare between the two methods.Material and Methods: twenty amalgam specimens were used: each was stored in 5 ml of normal saline solution for 1 month. The specimens were randomly grouped into two groups (group A and group B). Then the assessment of the corrosion was done by measuring of the released mercury, for group A is done by the atomic absorption method and for group B by the spectrophotometric method.Result: there is no statistical significant difference between two methods.Conclusion: the spectrophotometric method was successful alternative method to the atomic absorption methods in the assessment of the corrosion.

مقدمة :-تعتبر طريقة الامتصاص الذري الطيفي من أفضل الطرق وأدقها وأكثرها صحة في قياس مدى تآكل المعادن المستخدمة في طب الأسنان . قدمت الطريقة الطيفية مع استخدام مركبات معقدة ملونة وحساسة خاصة ايضا لقياس التاكل حيث انها طريقة اسرع واقل تعقيداَ . يهدف هذا البحث لاجراء مقارنة بين الطريقتين. المواد والطرق: اخذت عشرون عينة من كبسولات حشوات الاملغم ، وضعت بعد تحضيرها في 5مل من السائل الفسيولوجي الطبيعي وحفظت لمدة شهر في حاضنة بدرجة 37 درجة مئوية ، ثم قسمت عشوائيا الى قسمين : قسم أ وقسم ب تم قياس الزئبق المطروح في سائل الحفظ لعينات القسم أ بطريقة الامتصاص الذري اما القسم ب فقد تم القياس بطريقة الطيف مع المعقد الملون.النتيجة: لا فرق بين نتائج الطريقتين.الاستنتاج: طريقة القراءة الطيفية يمكن ان نعتبرها بديلا ناجحا لطريقة الامتصاص الذري في قراءة تآكل المعادن.


Article
Measurement of Mercury Concentration in Saliva of Selected Sample of Children in relation to Amalgam Fillings

Authors: Abdul Wahab T. Shakir عبد الوهاب شاكر --- Ban Ali Salih بان علي صالح
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2011 Volume: 23 Issue: special issue Pages: 134-140
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Dental amalgam fillings interact in a complex way with the environment in the oral cavity as they aresubjected to chemical, biological, mechanical, and thermal forces. These forces change the restoration’sappearance and properties, causing metal ions, amalgam debris, non-metallic corrosion products, and mercuryreleased into the oral cavity. The aims of this study were Measure the concentration of mercury in saliva of children inrelation to the number of amalgam fillings before and after chewing and measure the continuous release of mercuryvapor from amalgam fillings in children and its relation to gender and age.Materials and methods: The sample consists of 51 children between 8-10 years of age and they were divided intothree groups according to the number of amalgam fillings they have in their teeth (1st group children didn't haveamalgam fillings in their teeth, 2nd group children had 1-2 amalgam fillings, 3rd group children had ≥3 amalgamfillings). Then saliva samples were collected from each child before and after chewing of sugar free chewing gum insterilized disposable cups.Results: The results indicated that minute amount of mercury were continuously released from amalgam restorationsand the release is accelerated after stimulation (chewing).Also the results demonstrated a positive correlationbetween the number of amalgam fillings and mercury concentration in saliva, mercury in saliva of children whodidn't have amalgam fillings in their teeth may come from other sources such as air, water and food. There was norelation between mercury concentration in saliva of children and the gender and age of children

Keywords

children --- mercury --- saliva --- amalgam filling


Article
Synthesis of New Nucleoside Analogues from Theobromine

Authors: Thanaa M. Al-Mouamin --- Sumaya J. Abid
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2019 Volume: 00 Issue: 2 Pages: 17-29
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

Nucleoside Analogues play important role in different medical drugs,therefor we synthesized new nucleoside analogues using theobromine as a nucleobase, for the first time, by convertion to it's mercury salt, [1]. Then coupled with three kinds of sugar, including (glucose, galactose and mannose), after protection [2-4] and activation as bromo sugar [5-7] afforded blocked nucleoside analogues [8-10] which subsequently hydrolyzed to give our synthetic goal the free nucleoside analogues [11-13]. All prepared compounds were identify by FT-IR and some of them with 1H-NMR spectroscopy. The synthesized compounds (11-13) were screened for their in-vitro antibacterial and antifungal activity.


Article
Relation Between Serum Copper and Iron with Mercury Pollution in Dentists Used Amalgam Fillings
العلاقة بين العناصر الاساسية الحديد والنحاس والتلوث بالزئبق من خلال تعرض أطباء الاسنان للحشوات الزئبقية

Authors: Salah Alnuaimi صلاح الدين النعيمي --- Kawther Alzubaide كوثر عبدالرزاق الزبيدي --- Soud Turky Alazzawi سعاد تركي علي
Journal: Al-Ma'mon College Journal مجلة كلية المامون ISSN: 19924453 Year: 2018 Issue: 32 Pages: 341-355
Publisher: AlMamon University College كلية المامون الجامعة

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Abstract

The aim of this study is the investigation of copper and iron levels in blood serum of dentists exposed to mercury which was undertaken. from mercury dental amalgam preparation .The study includes (70) dentists divide into three groups according to the period of exposure (Group B exposed for (3-10) years), (Group C exposed for (10-15) years), (and Group D exposed for (15-30) years). Twenty healthy controls with no chance of exposure to mercury were chosen as control group (A). Mercury, copper and iron concentration were measured.The result revealed that copper level increased with duration of exposure compared to the control group. A decrease in iron level was noticed in all dentists group compared with the control. It’s concluded that mercury vapour from the dental amalgam could be a serious pollution poisoning source of dentists inhaling mercury vapor which inhibits some metabolic enzymes through their sulfhydryl (-SH) group. The alteration of essential and trace elements in the body could be due to damage the occur to the biological membranes and the imbalance of the ion transports across these membranes.

إن الهدف من هذه الدراسة هو قياس مستوى النحاس والحديد في مصل دم اطباء الاسنان الذين يستخدمون الزئبق في حشوة الاسنان الدائمية وذلك من خلال مزجه مع مسحوق السبيكة لتكوين مادة بلاستيكية تحشى في الحفرة المحضرة. كان عدد المتطوعين من اطباء الاسنان سبعين طبيباً وقد قسموا الى ثلاث مجاميع:(مجموعة (B) فترة التعرض (3 – 10) سنة)، (مجموعة (C) فترة التعرض ( 10- 15) سنة)، (مجموعة (D) فترة التعرض ( 15- 30) سنة). كما اخذت عينات من دم متطوعين اصحاء من غير العاملين في هذا المجال واعتبروا كمجموعة سيطرة (المجموعة A ) وعددهم (20) متطوعاً. اظهرت النتائج زيادة في تركيز النحاس وقلة في تركيز الحديد لدى العاملين بزيادة فترة التعرض مقارنة مع مجموعة السيطرة، مما يعطي دلالة على ان التعرض للزئبق من خلال تحضير الحشوة قد يؤدي الى التسمم بالزئبق نتيجة استنشاق الابخرة وقد يعزى ذلك الى ان ايون الزئبق يعمل على تثبيط بعض الانزيمات الايضية والحاوية على مجموعة الثايول (-SH) في الجسم كما ويعمل على عدم حصول موازنة في العناصر الاساسية والضئيلة نتيجة تضرر اغشية الخلايا الحية وعدم السيطرة على عمليات النقل خلال المضخات المختصة بعمليات نقل الايونات.


Article
Comparison Study between Dubinin-red Ushkevich and Temkin Model for Adsorption of Mercury onto Activated Carbon

Author: Hayder Mohammed Abdul-Hameed
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2008 Volume: 14 Issue: 1 Pages: 2331-2336
Publisher: Baghdad University جامعة بغداد

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Abstract

Activated carbon has been used as an adsorbent in this work to remove mercury from aqueous solutions. The aim of the work is to test how best activated carbon can be used as an adsorbent for mercury. Equilibrium isotherms, both, Dubinin-Redushkevich, and Temkin have been test. The batch experiments were conducted at room temperature (30oC) and at the normal pH (7.0±0.1) of the solution. HYBRID fraction error function analysis shows that the best-fit for the adsorption equilibrium data is represented by (D-R) model rather than Temkin model. Its found that the correction factor (R2) for (D-R) is 0.9928 while for Temkin model is 0.942, also the HYBRID fractional error was conducted for the both models and (D-R) model give minimum value of (0.0128) while it was (0.129) for Temkin.

يهدف البحث الى اجراء المقارنة لفاعلية موديلين رياضيين هما موديل Dubinin-Redushkevich وموديل Temkin لوصف عملية امتزاز الزئبق ضمن المحلول المائي باستخدام الكاربون المنشط . وقد تم اجراء التجارب المتقطعة في درجة حرارة 30ْ وقيمة (pH=7) وقد وجد ان معامل التصحيح (R2) للموديل الرياضي الاول يساوي (0.9928) بينما كانت القيمة للموديل الثاني تساوي (0.942) كذلك تم تطبيق معيار (HYBRID) الانحرافي للخطأ ووجد ان قيمته للموديل الاول يساوي (0.0128) بينما للموديل الثاني (0.129)


Article
Removal of mercury contamination from the dental clinic with metal backing for X-ray film

Author: Angham G. AL-Hashimi انغام الهاشمي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2005 Volume: 17 Issue: 2 Pages: 24-27
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Mercury in dental clinic has been recognized as a potential health hazard. This evaluated the removal of Hg spills from different surface in dental clinic with tin in the metal backing for dental x-ray film.Materials and Methods: Hg 90 drops (each one of 0.2 g) placed on 9 different surfaces in the dental clinic, and were divided into: Group I (protective surfaces) subgroup 1 (mask) subgroup 2 (gloves) subgroup 3 (dental apron)Group II (dental instrument and equipment) subgroup 1 (metals, for example, the metal tray of sterilizer) subgroup 2 (dental chair unit) subgroup 3 (wet surfaces, for example, the vacuum suction tank of the sucker). Group III (other clinical surfaces) subgroup 1 (working bench) subgroup 2 (the floor) subgroup 3 (the carpet). The metal backing for x-ray film (0.4 g) placed on each Hg spill, and the time of adsorption was recorded in seconds using a digital timer.Results: The results showed adsorption of Hg spills to the metal backing for x-ray film in all groups except in the crevice of the carpet. Group I subgroup 2 showed the faster interaction (7.1 + 2.828 sec.) while group II subgroup 3 showed the slowest interaction (90.3 + 20.981 sec.).Conclusion: Hg spills on dental protective surfaces can be removed easily, while the most difficult spills to be removed were on the wet surface. Furthermore, Hg spills in crevis of the carpet can not be removed

Keywords

Mercury --- metal backing --- x-ray film


Article
Urinary Mercury concentrations associated chewing gum in students of Faculty of Dentistry

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Abstract

The aim of this study was to measure the urinary mercury concentration instudents after chewing gum for certain period of time. Sixteen students from facultyof dentistry had used chewing gum for five hours a day for seven days. Urine samplecollected 24 h before and after the experimental time. Total mercury in urine (U-Hg)was determined by means of inductively coupled plasma mass spectrometry (ICPMS).t-test was used for the comparison of mercury before and after chewing gum. Anon significant difference was found after chewing than before chewing gum.


Article
Determination of Mercury concentration in the sediment and blood samples of fuel stations area using cold vapor atomic absorption spectrometry

Author: Ibrahim M. Jassim
Journal: journal of kerbala university مجلة جامعة كربلاء ISSN: 18130410 Year: 2010 Volume: 8 Issue: 4 Pages: 219-224
Publisher: Kerbala University جامعة كربلاء

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Abstract

A cold mercury vapor atomic absorption spectroscopy (CVAAS) Technique has been used for the determination of mercury in both of blood and sediment samples. After the blood Samples were digested in a mixture of (3:2:1) [Nitric, Perchloric and sulfuric concentrated acids] respectively and a sediment samples were digested in a mixture of (1:1) [Nitric and Hydrochloric concentrated acids] , a 25% (W/V) of Tin Chloride has been added as a reduction agent also a 1% (W/V) of Potassium dichromate have been added in order to improve sensitivity of measurements. The results show that average of mercury contents in the fuel stations worker blood samples are in range [22-36] ng/ml; whereas its contents in the fuel station area sediment samples are in range [30-48] ng/g.

تم استخدام طريقة الامتصاص الذري بتوليد بخار الزئبق البارد في تقدير محتوى الزئبق في عينات من الدم للعاملين في محطات تعبئة الوقود وكذلك والرواسب الترابية في محطات التعبئة. بعد عملية هضم عينات الدم بمزيج من (3 : 2 :1) من حوامض النتريك , البركلوريك والكبريتيك المركزة على التوالي , وهضم عينات الرواسب الترابية بمزيج من (1:1) من حامضي النتريك والهيدروكلوريك المركزين تم اضافة 25 % من مادة كلوريد القصديروز كعامل مختزل كما اضيفت 1 % من مادة داي كرومات البوتاسيوم لتحسين حساسية القياس.اظهرت النتائج بأن معدلات محتوى الزئبق في نماذج الدم للعاملين في محطات تعبئة الوقود تتراوح ضمن المدى (22-36) نانوغرام/ مليلتر بينما تكون معدلات المحتوى للزئبق في نماذج الرواسب الترابية تتراوح (30-48 ) نانوغرام /غرام.

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