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Article
Evaluation of Observed Energy From Adiabatic Impact on Composite Lamenates
تخمين الطاقة الممتصة نتيجة التصادم الاديباتي مع صفائح مركبة

Author: Kadhim H. Ghlaim
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2010 Volume: 28 Issue: 8 Pages: 1545-1567
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this paper, the energy observed due to impact of conical projectiles oncomposite laminates is investigated. Four types of energies observed were studied.They are strain energy due to deformation of plate, large deformation near theimpact zone, delaminating energy and energy losses due to friction.The equation of motion of plate was developed for orthotropic laminatedplate and solved with its boundary conditions. Large deformation of delaminatedzone was derived assuming deformation shape formulation to calculate thepenetration depth and delaminating radius. Delaminating energy was calculatedby solving the delaminating failure criteria with equation of motion. Frictionenergy was calculated assuming constant friction coefficient.The results show that the energy of deformation of plate is smaller thanthat for the large deformation and delaminating energy. And as cone angleincreases the energy observed will be increased and the depth of penetrationdecreases. Numerical and experimental results quoted in published papers show agood agreement with that of the presented work.

في هذا البحث تم التخمين النظري للطاقة الممتصة نتيجة اختراق اطلاقة جاسئة مخروطيةلصفيحة طباقية مركبة, تم تقسم الطاقات الممتصة الى اربعة انواع, هي طاقة الانفعال نتيجةتشويه الصفيحة, طاقة التشويه العالي حول منطقة الاصطدام, طاقة التفصخ و الطاقة الممتصةنتيجة الاحتكاك.اشتقت معادلة الحركة المطورة للصفيحة الطباقية المركبة وحلت بمعلوميةالشروط الحدية لها. كذلك تم معالجة منطقة التشويه العالي بطريقة مبتكرة هي طرية افتراضشكل التشويه ومن حلاله تم تخمين قطر منطقة التفصخ. ومن ثم تم احتساب طاقة التفصخباستخدام معامل التفصخ المعتمد وتعويضه في معادلة الحركة المطورة. بينما تم احتساب الطاقةالممتصة خلال الاحتكاك تحت فرضية ثبوت معامل الاحتكاك.اظهرت النتائج ان طاقة الانفعال الممتصةهي اقل من طاقة التشويه العالي و كذلك اقل منطاقة التفصخ. وكذلك اظهر النتائج زيادة في الطاقة الممتصة ونقصان في عمق الاختراق عندنقصان زاوية مخروط الاطلاقة. تم مقرنة النتائج مع اعمال عددية و عملبة منشورة وانتجتتوافقا مقبولا اثبت اهلية الحل النظري المقترح مع امكانية تطوير اكثر مستقبلا.


Article
A new technique for producing high-velocity liquid-like jet
طريقة جديدة لأنتاج نفث شبيه بالسوائل وعالي السرعة

Authors: Mazin Y.A مازن ياسين عبود --- Riyah N. K. رياح نجم كطر
Journal: Anbar Journal of Engineering Sciences مجلة الأنبار للعلوم الهندسية ISSN: 19979428 Year: 2008 Volume: 1 Issue: 2 Pages: 118-132
Publisher: University of Anbar جامعة الانبار

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Abstract

A new technique is presented by which lateral outflows of material , from an oblique impact collision between wax projectile and a rigid surface , are collected to form a high speed single jet. This jet has been shown to be capable of producing cavities in semi-infinite target of wax in a manner similar to that produced in a hypervelocity impact situation. The produced jet capability of penetration is found to be maximum at higher velocities of impact , lower values of standoff and with projectiles having angle of obliquity in the range (â=20-25o). A preliminary theoretical model is also presented in an attempt to describe the process of jet creation and jet characteristics. The present technique is proved to be promising in simulating penetration of semi-infinite targets by the impact of high speed jet .

يقدم هذا البحث طريقة جديدة وغير مسبوقة لأنتاج نفث شبيه بالسوائل وعالي السرعة وذلك باطلاق مقذوفات من الشمع ومجوفة مخروطيآ من المقدمة وجعلها تتصادم مع صفيحة جاسئة . وجد ان هذا النفث له القابلية على احداث فجوات في الاهداف السميكة المصنوعة من الشمع ايضآ وان هذه الفجوات شبيهة بتلك التي تنتج عن التصادم فائق السرعة . كما وجد ايضآ ان هذه القابلية تزداد بأزدياد سرعة المقذوفة وتقليل المسافة الفاصلة بين الهدف والصفيحة مع أستخدام تجاويف مخروطية للمقذوفة ذات زوايا ( o 20 o - 25 ) . قدم البحث ايضآ رؤيا نظرية تحليلية لوصف عملية انتاج هذا النفث والوقوف على خصائصه . أستنتج ايضآ ان هذه الطريقة واعدة لكي تستخدم في تطبيقات هندسية وخصوصآ في محاكاة التغلغل الحاصل في الأهداف السميكة نتيجة صدمها بنفث عالي السرعة


Article
A comparative study to evaluate the sealing ability of a prisma dycal placed in cervical root perforation versus other materials (in vitro study)

Authors: Ahmed H. Ali احمد علي --- Raghad A. Mohammed رغد محمد --- Shatha Abdul- Kareem شذى عبد الكريم
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2005 Volume: 17 Issue: 3 Pages: 1-3
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Calcium Hydroxide preparations are used extensively in dentistry, and one of these aspects is treatment of root perforations. The purpose of this in vitro study was to compare the sealing ability of a prisma (visible light cure dycal), amalgam with varnish and chemical cure dycal are used to repair lateral root perforations.Materials and Methods: Thirty extracted human maxillary anterior teeth were used; each tooth was sectioned longitudinally into facial and palatal halves .The perforations were made into each half tooth at the cervical third of the root. The samples were divided into three groups; group I was repaired with prisma, group II repaired with chemically cured dycal and group III with varnish and amalgam .The teeth halves were placed in methylene blue dye for one week period then linear dye penetration was measured from where the repair materials were made.Results: The results showed that a prisma (visible light cure dycal) demonstrated less dye penetration than other groups, the difference was statistically significant (p<0.01) from other groups, non significant differences (p>0.05) were present between amalgam with varnish and the chemically cured dycal.Conclusion: Calcium Hydroxide including the visible light cured and the chemically cured, and the amalgam with varnish, each possess a therapeutic potential for treating known and undetected root perforations. Percentage of leakage was more in amalgam with varnish group than prisma and Kerr Dycal


Article
Estimation of Rate of Penetration Considering Mechanical, Hydraulic, and Formation Characteristics for Mishref Formation

Author: Kadhim Hmood Mnati
Journal: Journal of Petroleum Research & Studies مجلة البحوث والدراسات النفطية ISSN: 22205381 Year: 2017 Issue: 17 Pages: E20-E38
Publisher: Ministry of Oil وزارة النفط

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Abstract

This paper presents a detailed formulation of a rate of penetration (ROP) model, considering many drilling parameters and conditions for obtaining maximum drilling rate as well as minimizing the drilling cost.A regression analysis technique has been usedfor ROP modeling in Mishref formation.The data were extracted from routinely available mud and wirelinelogs. These data includes weight on bit ,rotary speed,horse per square inch,and transit time.For ROP modeling, data of five wells inHalfaya oil field in south Iraq were extracted.Statistical software called SPSS was used for improving the modeling data and to perform linear and nonlinear multiple regression analysis. This improving approach included detection the outliers of modeling parameters, grouping the modeling data, moving average and finally applying the regression analysis.Results of modeling showed that the grouping of modeling data exhibited good convergence with actual data and the overall model of oil field could producegood fitness with the actual data in both cases of linear and nonlinear models.Also,a good estimation of drilling cost could be obtained when using this model.


Article
An evaluation the sealing ability of a three retro-filling materials

Author: Raghad A. Mohammed رغد محمد
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2005 Volume: 17 Issue: 2 Pages: 5-7
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Retro end filling is important to establish a seal between the root canal space and the periapical tissue. The purpose of this in vitro study was to evaluate the quality of seals obtained with various retro-grade filling materials using dye penetration method of micro leakage measurement.Materials and methods: Forty extracted human single rooted teeth were used. Following root canal obturation, 30 teeth were divided into three experimental groups and each group was subjected to one of the three filling techniques: acold burnishing of gutta percha, bcalcium phosphate cement, csuper EBA cement. The remaining 10 teeth were considered as a control group. The teeth were placed in methylene blue dye for a period of 10 days after which they were washed, sectioned and the apical dye penetration measured.Results: The results showed that (CPC) and super EBA cement demonstrated less dye penetration than other experimental groups; the difference was statistically significant as compared with groups 1 & 4 and not significant as compared between groups 2&3.Conclusion: A general trend was observed that the apical leakage was found in all teeth but with different degrees, some leaked more than others, dye penetration was more with the cold burnished gutta percha


Article
The effect of canal size on the penetration depth of endodontic irrigants

Author: Nawfal A Zakaria
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2006 Volume: 6 Issue: 11 Pages: 84-87
Publisher: Mosul University جامعة الموصل

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Abstract

Aim: To evaluate the effectiveness of canal size change on the penetration level of endodontic irrigant solution. Materials and Method: Five canals of different sizes (20, 25, 30, 35 and 40) were tested by preparing Class I cavity in the apex. Paper point was placed in this cavity and sealed 4 mm by sticky wax. Irrigation was done by methylene blue solution 15 times for each canal size, then the paper point piece examined under stereomicroscope for discoloration and wetness. Results: The irrigant solution was penetrated up to the apical area of the all canal sizes in the all 15 irrigation trials. The volume of fluid, the degree of fairing, the use of apical patency files, and the needle depth were the other different factors improving penetration depth of irrigating solution. Conclusions: There was no effect of canalsize on the penetration level of the endodontic irrigant.


Article
The effect of subsoiler (double tines ) plow on some physical and mechanical properties for silty clay soil
تأثير محراث تحت التربة ( ثنائي الأسلحة ) على بعض الصفات الفيزيائية و الميكانيكية للتربة الغرينية طينية

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Abstract

This research was conducted by a subsoiler (double tines ) plow of mounted type to study its effect on the mechanical and physical soil properties (soil bulk density, soil penetration resistance and soil cohesion ) . The experiments using four depth (25,35,45and 55 cm ) in eultiuoted and uneultiuoted silty clay soils . The results showed that the subsoiler plow reduced the soil bulk density ,soil penetration resistance and soil cohesion by 25% ,78% and 82% respectively . The subsoiler had greater effection the three soil properties as the plowing depth increased especially at plowing depth of 50 cm .

تضمن البحث استخدام محراث تحت التربة ثنائي الأسلحة المعلق على جرار ماسي فركسن لمعرفة تأثير المحراث على بعض الخواص الفيزيائية و الميكانيكية والتي شملت الكثافة الظاهرية ومقاومة التربة للاختراق و قوة التماسك في التربة .


Article
Correlation of Penetration Rate with Drilling Parameters For an Iraqi Field Using Mud Logging Data

Author: Hassan Abdul Hadi
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2015 Volume: 16 Issue: 3 Pages: 35-44
Publisher: Baghdad University جامعة بغداد

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Abstract

This paper provides an attempt for modeling rate of penetration (ROP) for an Iraqi oil field with aid of mud logging data. Data of Umm Radhuma formation was selected for this modeling. These data include weight on bit, rotary speed, flow rate and mud density. A statistical approach was applied on these data for improving rate of penetration modeling. As result, an empirical linear ROP model has been developed with good fitness when compared with actual data. Also, a nonlinear regression analysis of different forms was attempted, and the results showed that the power model has good predicting capability with respect to other forms.


Article
Prediction of penetration Rate and cost with Artificial Neural Network for Alhafaya Oil Field
تخمين معدل الحفر والكلفة بواسطة الشبكة العصابية الصناعية لحقل الحلفاية النفطي

Authors: Kadhim Hmood Mnati --- Hassan Abdul Hadi
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2018 Volume: 19 Issue: 4 Pages: 21-27
Publisher: Baghdad University جامعة بغداد

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Abstract

Prediction of penetration rate (ROP) is important process in optimization of drilling due to its crucial role in lowering drilling operation costs. This process has complex nature due to too many interrelated factors that affected the rate of penetration, which make difficult predicting process. This paper shows a new technique of rate of penetration prediction by using artificial neural network technique. A three layers model composed of two hidden layers and output layer has built by using drilling parameters data extracted from mud logging and wire line log for Alhalfaya oil field. These drilling parameters includes mechanical (WOB, RPM), hydraulic (HIS), and travel transit time (DT). Five data set represented five formations gathered from five drilled wells were involved in modeling process.Approximatlly,85 % of these data were used for training the ANN models, and 15% to assess their accuracy and direction of stability. The results of the simulation showed good matching between the raw data and the predicted values of ROP by Artificial Neural Network (ANN) model. In addition, a good fitness was obtained in the estimation of drilling cost from ANN method when compared to the raw data.

التخمين الدقيق لمعدل الحفر ذو اهمية كبيرة في الحفر الامثل بسبب تاثيره المحوري على كلفة عمليات الحفر. وعادة يكون هذا التخمين صعب بسبب تداخل العوامل التي تؤثر على عملية الحفر.في هذا البحث تم استخدام طريقة الشبكة العصابية الصناعية كاسلوب جديد لتخمين معدل الحفر والكلفة ,حيث تم بناء موديل الشبكة العصابية من ثلاثة طيقات اثنان مخفية وواحدة للنواتج باستعمال بيانات مجسات الطين والمجسات الاخرى لحقل الحلفاية النفطي. العوامل التي تم اسخدام قيمها هي العوامل الميكانيكية (الوزن المسلط ,سرعة الدوران),العوامل الهيدروليكية,وزمن انتقال الموجة الصوتية . تم استخدام خمس مجاميع للبيانات والتي نمثل خمس تكوينات في الحقل حيث تم استخدام 85%من البيانات لتدريب الموديل و15% لاختبار صلاحيته. بينت النتائج التطابق الجيد لقيم معدل الحفر المحتسبة من الموديل مع القيم المقاسة وكذلك لقيم الكلفة المحتسبة مع القيم الاصلية.


Article
Tissue penetration of Toxoplasmosis in experimental rats

Author: Zahraa Sadoon Al-Ghezy
Journal: Journal of Education for Pure Science مجلة التربية للعلوم الصرفة ISSN: 20736592 Year: 2017 Volume: 7 Issue: 3 Pages: 150-160
Publisher: Thi-Qar University جامعة ذي قار

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Abstract

Abstract:Toxoplasma gondiiis an intracellular protozoa, widespread throughout the world, and it has theability to infect many organs in the body such as the brain, eyes, liver and spleen.In this study, 56rats(28 males and 28 females) were divided into two groups, the first group28 rats(14 male and 14female) was inoculated with normal saline to serve as control,and the second group 28 rats(14 maleand 14 female)was infected intraperitonealy with placental fluid containing1×107tachyzoites ofToxoplasma gondii. After 2 months of infection, the infection was confirmed by using real-timePCR, and the animals were scarified. Brain, liver and spleen tissues were fixed in 10% formalin forhistological examination.The results indicated that the parasite invaded many tissues and causedmany histopathological changes. The parasite (tissue cyst stage containing bradyzoite and tachyzoitestage) were recorded in the braintissues of both males and females.The brain tissues also revealedmany histological changes included inflammatory manifestations and a wide areas of edema. Thegroups of laboratory rats which infected with T. gondii showed several histological changes in theliver tissue, included congestion of the central vein, expansion of the jaundice and accumulation ofthe inflammatory cells in several sites of the liver. The spleen of infected group showed hemorrhage,extra-medullary mega karyocytosis, necrosis, fibrosis and degeneration of spleen tissues.

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