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Article
Analytical Investigation of Charging Ability of Insulators under Electron Beam Irradiation inside SEM Chamber

Author: Hassan N. Al-Obaidi1, Ali S. Mahdi2
Journal: Almuthanna Journal of Pure Science (MJPS) مجلة المثنى للعلوم الصرفة ISSN: 22263284 Year: 2016 Volume: 3 Issue: 2
Publisher: Al-Muthanna University جامعة المثنى

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An analytical procedure has been carried out to measure the charge that may trapped in an insulator sample andrelated electrostatic surface potential in sense of mirror effect phenomenon. In fact, scanning electron microscope mirrormethod (SEMME), sometimes called electron mirror method (EME) and/or magnification factor method (MFM), has beenused to accomplished that purpose. However, this work has been carried out concerning the theoretical point of view, themirror plot curve has been adopted as an evaluation scale for the quality of the mirror image. Therefore, this procedure hadbeen used to investigates the experimental mirror plot curves for PMMA material with different accelerating potential andstudying the most important parameters that affects in these curves. Results have clearly shows that the radius of irradiatedarea play an important rule in the shape of mirror plot figure and then the quality of the image.


Article
A scanning electron microscopical study of initial changes in human premolars teeth after orthodontic tooth movement

Author: Dalia Kubad Taher, B.D.S., M.Sc د. داليا طاهر
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2005 Volume: 2 Issue: 2 Pages: 230-234
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

scanning electron microscope was used to study the effect of orthodontic tooth movement by using a force of 50 grams on the pressure side of 2l upper left premolarmt for 5- 75 days while the contralaterl side 14 teeth were used as a control. In order toruiy the morphology and occurrence of root resorptions, the organic tissue was removedrsigg sodium hypochlorite and the denuded root surface were re—examined in thescanning electron microscope. Initially, tissue affected by pressure was mainly located inhe marginal region and subsequently the mid- portion of the roots became generallyuri genced. The resorption process of cementum begins after 5 days as around cavitiesmeasuring about 4u. Further resorption in cementum was characterized by measuringsmall, thin—walled round lacunae which confluence into extensive, shallow resorptionsafter 25 days and more


Article
Easy and New Chemical Synthesis of Stable Nano Sliver using Propylene Glycol and Glycerin as Reducing Agents

Authors: Abdulah A. Mohammed --- Sarab T. Mahmood
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 2 Part (B) Engineering Pages: 131-135
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this present work we have synthesized stable silvernanoparticles (Ag-NPs) by chemical reduction with aqueous solutions ofsilver nitrate (i) propylene glycol (ii) glycerin as reducing agents and guargum as a stabilizer. The reaction were done at room temperature and atpH=8. Systematic characterizations of the Ag-NPs were done using UV-Vis,zeta potential analysis, X-Ray diffraction (XRD), AFM and SEM whichreveal stable Ag-NPs. These measurements indicate that the particles aremostly spherical in shape. The UV-Vis spectra of the result solution of AgNPsshow an absorption peak at 412 nm and 424 nm for using propyleneglycol and for using glycerin respectively. These color occurring due toSurface Plasmon Resonance (SPR). The SEM measurements gave a particlesize of 40 -70 nm. Nano silver showed stability for long periods of time tomore than nine months, and this can be an economical and effective way forwide scale synthesis of Ag-NPs which applicable for various medicaltherapies.


Article
Evaluation of marginal gap at the composite/enamel interface in Class II composite resin restoration by SEM after thermal and mechanical load cycling (An in vitro comparative study)

Authors: Mais Yaroub ميس يعرب --- Mohammed R. Hameed
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 4 Pages: 63-70
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study compared in vitro the marginal adaptation of three different, low shrink, direct posteriorcomposites Filtek™ P60 (packable composite), Filtek™ P90 (Silorane-based composite) and Sonic fill™ (nanohybridcomposite) at three different composite/enamel interface regions (occlusal, proximal and gingival regions) of astandardized Class II MO cavity after thermal changes and mechanical load cycling by scanning electronmicroscopy.Materials and methods:Thirty six sound human maxillary first premolars of approximately comparable sizes weredivided into three main groups of (12 teeth) in each according to the type of restorative material that was used:group (A) the teeth were restored with Filtek™ P60 and single bond™ Universal adhesive using horizontal incrementaltechnique, group (B)the teeth were restored with Filtek™ P90 and P90 system adhesive using horizontal incrementaltechnique and group (C) the teeth were restored with Sonic fill™ composite and single bond™ Universal adhesiveusing bulk technique.After specimens were stored in distilled water at 37°C for 7 days, all specimens were subjectedto thermocycling at (5° to 55 °C), then submitted to mechanical load cycling (intermittent axial force of 49N and atotal of 50.000 cycles). The specimens were observed under scanning electron microscope at (2000 X) to measuremarginal gap width (the distance between the dental wall and the restoration) at occlusal, proximal and gingivalregions in micrometer using Tescan software, version 3.5. Data were analyzed statistically by one way ANOVA testand least significant difference tests.Results:The results showed that the silorane-based posterior composite (Filtek™ P90) showed significantly the leastmarginal gap width at the occlusal, proximal and gingival regions after the application of thermal changes andmechanical load cycling in comparison to the two methacrylate-based posterior composite Filtek™ P60 (packable)and the Sonic fill™ (nano-hybrid). Sonic fill™ bulk fill composite that relied on the vibration concept to lower theviscosity of high filler loaded composite material showed significantly lesser marginal gaps width at occlusal, proximaland gingival composite/enamel interface regions in comparison with Filtek™ P60 (packable composite) usinghorizontal incremental technique. The silorane-based composite (Filtek™ P90) showed non-significant difference inmarginal gaps width at the three different regions. While, both methacrylate based Filtek™ P60 and Sonic fill™composite showed significantly lesser marginal gap width at the occlusal region in comparison with gingival regions.Conclusion: None of the low-shrinkage composite restorative materials tested in this study totally prevented microgapformation at composite/enamel interfaces of Class II MO cavity


Article
The Effects of Nano-Hydroxyapatite and Casein Phosphopeptide-Amorphous Calcium Phosphate in Preventing Loss of Minerals from Teeth after Exposure to an Acidic Beverage (An In vitro Study)

Authors: Shahad Zahed Al-Janabi شهد زاهد الجنابي --- Zeyneb A.A. Al-Dahan
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2015 Volume: 27 Issue: 4 Pages: 132-137
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This study aimed to evaluate the effect of antierosive agents (10% Nano-Hydroxyapatite (NHA), 10%Casein Phophopeptide-Amorphous Calcium Phosphate (CPP-ACP), and combination of 10% NHA and 10% CPPACP)on loss of minerals from enamel surface of permanent teeth treated with antierosive agents when exposed toan acidic beverage and investigate the morphological changes of treated enamel surface after demineralizationwith cola based beverage under Scanning Electron Microscope (SEM).Materials and Methods: Sixty maxillary first premolars were randomly divided into four groups, 15 teeth for eachgroup. Group I treated with 10% NHA, Group II treated with 10% CPP-ACP, Group III treated with 10% NHA and 10%CPP-ACP, and Group IV did not treat with any remineralizing agents. The teeth were immersed in the remineralizingsolutions (10% NHA, 10% CPP-ACP, and combination of 10% NHA and 10% CPP-ACP) for 4 minutes twice daily for 28days and then stored in the artificial saliva. The samples were immersed for 40 minutes in 20 ml Pepsi cola (PH=2.5).Atomic Absorption Spectrophotometer (AAS) was used to record the calcium and phosphorus concentrationsinPepsi cola before and after demineralization with cola based beverage. SEM also usedto examine themorphological changes occurs in enamel surface of each group after demineralization with cola based beverage.Results: Statistically, there is a highly significant increase in calcium concentration in Pepsi cola (mg/dl) afterdemineralization with cola based beverage. Group I showed the lowest changes in calcium concentration valuesamong the three studied groups. Group II was the next, which also showed lower changes in calcium concentrationvalues, then group III while the highest changes were recorded in group IV. There is a highly significant reduction inphosphorus concentration in Pepsi cola (mg/dl) after demineralization with cola based beverage. Group I showedthe lowest changes in phosphorus concentration values among the three studied groups. Group II was the next,which also showed lower changes in phosphorus concentration values, then group III while the highest changeswere recorded in group IV. Statistically, a highly significant difference was showed in calcium and phosphorusconcentrations between the four studied groups after demineralization with cola based beverage. Group IV has ahighly significant difference in comparison to group I, group II, and group III.Conclusions: Both the remineralizing agents (NHA and CPP-ACP) were found to be effective in inhibiting thedemineralization caused by cola based beverage.The combination of NHA and CPP-ACP had no synergistic effecton remineralization


Article
Agent Based Monitoring For Investigation Process And Maintenance Improvement

Authors: Soroor K.Hussain --- Zouhair I. Ahmed --- Ameer Hussein Ali
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2011 Volume: 17 Issue: 5 Pages: 1269-1288
Publisher: Baghdad University جامعة بغداد

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Abstract

Agent technology has a widespread usage in most of computerized systems. In this paper agent technology has been applied to monitor wear test for an aluminium silicon alloy which is used in automotive parts and gears of light loads. In addition to wear test monitoring, porosity effect on wear resistance has been investigated. To get a controlled amount of porosity, the specimens have been made by powder metallurgy process with various pressures (100, 200 and 600) MPa. The aim of this investigation is a proactive step to avoid the failure occurrence by the porosity.A dry wear tests have been achieved by subjecting three reciprocated loads (1000, 1500 and 2000)g for three periods (10, 45 and 90)min. The weight difference after each test is immediately measured to find the losing weight and wear rate for each specimen. Wear test was monitored online by two sensors, force sensor to control the applied load, find friction force and coefficient of friction. The sensor is an acoustic emission to detect crack initiations of the worn surface by transfers the emitted ultrasonic waves from crack initiations to electric signals. Scanning electron microscope has been used to examine the worn surfaces. The overall results include that the effect of pores depends on pore shapes, sizes and concentrations.

تقنية العميل لها استخدام واسع في معظم الأنظمة المسيطر عليها بواسطة الحاسوب. في هذا البحث تم تطبيق تكنلوجيا العميل لمراقبة فحص البليان لسبيكة الأمنيوم سليكون التي تدخل في صناعة اجزاء السيارات ومنتجات اخرى كتروس اللأحمال الخفيفة. بالاضافة الى مراقبة فحص البلي, تم التحقيق من تأثير المسامية على مقاومة البليان. للحصول على كمية مسيطر عليها من المسامية تم تصنيع العينات بواسطة عملية مساحيق المعادن مع ضغوطات متغيرة (100, 200 و600) ميكا باسكال. الهدف من هذا الفحص هو الخطوة الاستباقية لتجنب حدوث الفشل الناتج من المسامية.اختبارات البلي الجاف قد انجزت عن طريق تسليط ثلاثة احمال تبادلية (1000, 1500 و2000) غم لثلاث فترات (10, 45 و 90) دقيقة. تم قياس الفارق بالوزن مباشرة بعد اختبارات البلي الجاف قد انجزت عن طريق تسليط ثلاثة احمال تبادلية (1000, 1500 و2000) غم لثلاث فترات (10, 45 و 90) دقيقة، وتم قياس الفارق بالوزن مباشرة بعد كل عملية فحص لإيجاد فقدان الوزن ومعدل البلي لكل عينة. اما فحوصات البلي تم مراقبتها بصورة مباشرة بواسطة متحسسين، احدهما متحسس القوى واستخدم لضبط الحمل المسلط ، ايجاد قوة الإحتكاك و معامل الاحتكاك. اما المتحسس الاخر هو متحسس الانبعاثا ت الصوتية لكشف بدايات التصدع في السطح المبلي عن طريق تحويل الموجات فوق الصوتية المنبعثة من بداية التصدع الى اشارة كهربائية. تم استعمال المجهر الماسح الألكتروني لفحص السطوح البالية. تضمنت النتائج بشكل اساس ايجاد تأثير المسامية على مقاومة البليان الذي يعتمد على شكل وحجم وتراكيز المسامات على في المعدن


Article
Design and Fabrication of the Single Polepiece Magnetic Electron Lens of Truncated Cone Polepiece Shape
تصميم وتصنيع عدسة الكترونية مغناطيسية أحادية القطب ذات قطب مخروطي الشكل ناقص

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Abstract

AbstractThe magnetic electron objective lens is of a great importance which limit the resolving power of the electron microscope.The present work investigates the objective focal properties of a single polepiece magnetic electron lens of truncated cone polepiece shape of the selected geometrical dimensions for practical applications. The lens has been fabricated consist of cast shield made of mild steel combined with exciting isolated cooper coil of 500 turns.The theoretical and experimental results presented the magnetic flux density distribution and the objective focal properties of the lens, in mode of operation when the direction of incident electrons beam facing the lens back plate of the lens.Moreover, the theoretical and experimental results are in a good agreements.Keywords: electron optics, magnetic lens fabrication, design of magnetic lens, objective properties, low voltage scanning electron microscope.

الملخصتعد العدسة الالكترونية المغناطيسية الشيئية ذات أهمية كبيرة في المجهر الالكتروني حيث تحدد قدرة تحليله. تناول البحث الحالي استقصاء الخواص البؤرية الشيئية لعدسة الكترونية مغناطيسية ذات قطب أحادي مخروط ناقص الشكل، وتم اختيار أبعادها الهندسية لتلائم التطبيق العملي. صنعت العدسة الالكترونية بغلاف متكون من سبيكة الفولاذ والملف المهيج لها يتكون من (500) لفه من سلك نحاسي معزول. تم الحصول على نتائج توزيع كثافة الفيض المغناطيسي والخواص البؤرية الشيئية للعدسة نظرياً وعملياً، في نظام التشغيل لسقوط الحزمة الالكترونية بالاتجاه المقابل للوح الخلفي للعدسة.فضلا عن ذلك تمت مقارنة النتائج النظرية والعملية وأظهرت أن هنالك توافقاً جيداً


Article
Detection of white mice intestinal immune response against the external surface of Hymenolepis nana by scanning electron microscope
الكشف عن مظاهر الاستجابة المناعية المعوية للفئران المهق تجاه سطح الدودة الشريطية المحرشفة القزمة بواسطة المجهر الاليكتروني التفراسي

Author: Jasim Hameed Taher جاسم حميد طاهر
Journal: Al-Qadisiyah Journal of Veterinary Medicine Sciences مجلة القادسية لعلوم الطب البيطري ISSN: 18185746 23134429 Year: 2016 Volume: 15 Issue: 1 Pages: 54-57
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

The aim of the study was involve the scanning electron microscope to detect any damage to the surface of the Hymenolepis nana worm at different ages due to host intestinal immune response. Fifteen male albino Balb/c mice were used in this experiment. The eggs suspension obtained from gravid proglottid was given to mice by administration tube. The infected mice were killed at different intervals. The intestines of mice were opened and the worms allowed to release. These worms were examined by electron microscope. The results as observed; the surface of the scolex has a smooth structure in both 30 and 63 days old worm. The neck surface was smooth at 10 days and at the 30 and 63 days old worms was pitted. There were puff-like cells attached to the surface; these were lymphocytes, and may be eosinophil. Similar damage was seen on the tegument of posterior part of the worm. We can conclude that there is a progressive destruction of tegument as worm ages, and this is believed to be a consequence of immune response.

هدفت الدراسة الى استخدام المجهر الالكتروني التفراسي للكشف عن الضرر الحاصل لسطح الدودة الشريطية المحرشفــة القزمـة المخمجة للفأر الامهق لمختلف الاعمار نتيجة الاستجابة المناعية المعوية ، استخدمت في الدراسة 15 من ذكور الفأر الامهق. اعطي للفأر عن طريق انبوب الاعطاء معلق البيوض المأخوذ من القطع الحبلى للدودة ، وقتلت الفئران المخمجة على فترات زمنية مختلفة ، وفتحت امعاء الفئران وجرى تحرير الديدان وفحصها باستخدام المجهر الالكتروني. لوحظ من النتائج إن رويس الدودة كان أملسا في عمر 30و63 يوما ، أما عنق الدودة فقد كان أملسا في عمر 10 أيام في حين كان منقرا في عمر 30 و63 يوما. لقــد شوهدت خلايا نفيشة قد تماست مع سطـــح العنق والتـي هي خلايا لمفاويـة إضافة إلى خلايا أخرى قد تكون من الحمضات كما إن ضررا قد لحق بالجزء الخلفي من لحافة الدودة ، أما الشدفة الطرفية الخلفية في عمر 10أيام فقد كانت ملساء ومنقرة ، في حين كانت في عمر 30 و 63 يوما ) والتي من الممكن ان تنفصل عن جسم الدودة ( فأن سطحها يكون منقرا بحاله شبيهه بما موجود في العنق ووجود خلايا يظن أنها من الحمضات والتي تشاهد غالبا بأعداد كبيره.


Article
Design of the illumination system in the field emission Scanning Electron Microscope (SEM)
تصميم منضومة الاضاءة في المجهر الالكتروني الماسح ذو الانبعاث المجالي

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Abstract

The main goal of This Work is to survey the field emission scanning electron microscope (SEM) to obtain on the optimal design for illumination system. The SEM optical column contains of illumination system that form a focused beam by electrons are released and animated to incident on the specimen surface, this backscattered electrons from the specimen surfaces, finally forming an image. mainly the optical column include a field emission source as the beam source, illumination system, electron control unit, and unit the vacuum. use of a finite element analyses in the design process of the SEM ingredient to be optimally determined. By the analysis we can predict the beam emission characteristics and relevant trajectories were predicted from the analysis of the present work from which a systematic design of the electron optical system is enabled.

يهدف هذا العمل الى دراسة تصميم منظومة الاضاءة في المجهر الالكتروني الماسح ذو الانبعاث المجالي . يتالف العمود البصري للمجهر الالكتروني الماسح من منظومة الاضاءة التي تنبعث خلالها الالكترونات لتشكل حزمة مبئرة تسقط على سطح العينة ثم تنعكس تلك الالكترونات من سطح العينة لتشكل الصورة . يتالف العمود البصري بصورة اساسية من قاذف الانبعاث المجالي كمصدر للحزمة , منظومة العدسات , وحدة السيطرة علي الالكترونات , وحدة التفريغ. يستعمل تحليل العناصر المحددة في تصميم مكونات المجهر الالكتروني الماسح للحصول على تصميم مثالي , خلال التحليل خصائص مسار الحزمة المنبعثة متوقع من خلال التصميم التخطيطي لمنظومة الاضاءة الالكترونية


Article
Investigation of Superhydrophobic/Hydrophobic Materials Properties Using Electrospinning Technique
التحقق من خصائص مواد نافرة للماء/كاره للماء بأستخدام تقنية البرم الكهربائي

Authors: Hassan Talal Jaafar حسن طلال جعفر --- Balqees Mohammed Diaa Aldabbagh بلقيس محمد ضياء الدباغ
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2019 Volume: 16 Issue: 3 Pages: 632-638
Publisher: Baghdad University جامعة بغداد

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Abstract

The aim of this research is to study the surface alteration characteristics and surface morphology of the superhydrophobic/hydrophobic nanocomposite coatings prepared by an electrospinning method to coat various materials such as glass and metal. This is considered as a low cost method of fabrication for polymer solutions of Polystyrene (PS), Polymethylmethacrylate (PMMA) and Silicone Rubber (RTV). Si were prepared in various wt% of composition for each solutions. Contact angle measurement, surface tension, viscosity, roughness tests were calculated for all specimens. SEM showed the morphology of the surfaces after coated. PS and PMMA showed superhydrophobic properties for metal substrate, while Si showed hydrophobic characteristics for both metal and glass substrate. Polymer solution of (15%Si/Thinner (Th)) owned best roughness for glass substrate and polymer solution of (4%PMMA/Tetrahydrofuran (THF)) owned best roughness for metal substrate.

الهدف من هذا البحث هو دراسة خصائص التغيرات الحاصلة على السطح لطلاءات متراكبة نانوية طارده للماء محضرة بطريقة البرم الالكتروني والتي تعتبر كطريقة غير مكلفة للتصنيع. تم طلاء اسطح مختلفة من الزجاج والمعدن حيث تم تحضير المحلول البوليمري لكل من البوليمرات البولي ستايرين, بولي مثيل ميثا كريليت والسيليكون بنسب مختلفة لكل محلول. تم اجراء اختبار مقياس زاوية التماس للاسطح قبل وبعد الطلاء لغرض معرفة الترطيب الحاصل على السطح . واختبار الشد السطحي واللزوجة وخشونة السطح لجميع النماذج المحضرة. تم الفحص بالمجهر الالكتروني الماسح أيضا لإظهار مورفولوجيا السطح بعد الطلاء. أظهرت النماذج بعد الطلاء بمادة البولي ستايرين ومادة البولي مثيل ميثا كريليت خصائص طارده للماء للسطح المعدني بينما اظهرت النماذج بعد الطلاء بمادة السيليكون خصائص طارده للماء للسطحين المعدن والزجاج. امتلاك المحلول البوليمري المحضر بنسبة 15%Si/Th افضل خشونة لسطح الزجاج وامتلاك المحلول البوليمري المحضر بنسبة4%PMMA/THF افضل خشونة لسطح المعدن.

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