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Article
Study of Heat Storage in Shallow Fluidized Beds
دراسة الخزن الحراري في الطبقات المميعة الضحلة

Author: Burhan Mahmood Ahmad Al-Ali الدكتور برهان محمود احمد العلي
Journal: AL Rafdain Engineering Journal مجلة هندسة الرافدين ISSN: 18130526 Year: 2011 Volume: 19 Issue: 3 Pages: 69-75
Publisher: Mosul University جامعة الموصل

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Abstract

AbstractThis paper presents the theoretical analysis and experimental study of the performance of a shallow fluidized bed as a storage system for thermal energy.River sand is used as a bed with different height values and compressed heated air as an external fluidizing.A bundle of finned tubes is used as a heat exchanger immersed in the bed for the extraction of stored energy from the bed.Empirical correlations are offered by experimental work, which show the relations between the instantaneous local temperature within the bed and time as a function of both bed height and inlet air velocity. Keywords: Heat, Transfer, Fluidized Beds, Heat Storage,.

المستخلصيقدم هذا البحث دراسة عملية وتحليل نظري لأداء مبادل حراري يعمل بالطبقات المميعة الضحلة عند خزن الحرارة فيه.استخدم الرمل النهري وبارتفاعات مختلفة كطبقة مميعة ، والهواء المضغوط الساخن كمميع خارجي.استخدمت في البحث حزمة من الأنابيب المزعنفة كمبادل حراري مغمور داخل الطبقة من اجل حساب كمية الحرارة المخزونة في الطبقة. كما يعرض البحث مجموعة من المعادلات التجريبية والتي تم التوصل أليها من خلال الجزء العملي والتي تربط بين درجة الحرارة الموضعية والوقت اللازم لشحن المنظومة بدلالة ارتفاع الطبقة وسرعة الهواء.


Article
Influence of Heating Rates and Residual Monomer on Dimensional Changes of Acrylic Resin Denture Base

Author: Dr.Ghassan A. Al-Taie, BDS, MSC.* د.غسان الطائي
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2008 Volume: 5 Issue: 4 Pages: 393-397
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background: Most of spaces between the denture base and master cast produced by shrinkage of the base material during polymerization and by the difference in coefficient of thermal expansion of the cast and acrylic resin. The aim of this study is to evaluate the effect of the different heating rates and the presence of residual monomer on the accuracy different curing denture base by recording the gap space between the cast and the dentureMaterials and methods: 18 maxillary edentulous stone cast were prepared then divided into three main groups, denture bases were constructed. In Group A, using Biostar plates (free of monomer) in the pressure champers. In group B, using short curing cycle while group C, using long curing cycle . The gap space between the cast and denture base was recorded using traveling microscope measuring device.Results: Biostar curing resin (group A) showed significantly the highest dimensional changes among groups (short and long curing resins). There was no significant difference between group B ( short curing resin) and group C (long curing resin). The lowest gap space values were obtained in long curing resin. All samples showed maximum discrepancy in mid palatal reign and minimum dimensional changes at the crest of ridge. Minimum gap space values were shown in the canine reign for record bases cured with short and long curing cycles, while minimum gap space values were shown in the posterior palatal seal for record base cured with Biostar machine.Conclusion: The dimensional changes of record bases mainly depend on the amount of heat applied during processing rather than the amount of residual monomer. Greater distortion was shown in record base processed by Biostar machine (Free of monomer), while the least distortion in record base processed by long curing cycle. All samples showed maximum discrepancy in the mid palatal region and minimum dimensional changes at the crest of ridge.


Article
Effect of Supplementation of Withania somnifera L. Roots on Some Blood Physiological Parameters of Japanese Quail Hens Reared Under High Environmental Temperature

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Abstract

Abstract:An experiment was conducted to assess the antistress efficacy of Withania somniferaroots ethanolic on some blood physiological traits of Japanese quail hens reared under highenvironmental temperature (27-37-27ºC).Three hundred Japanese quail hens of six weeks old were randomly distributed intofive treatments T0 untreated group (control), T1, T2 quails supplemented orally with 50, 100mg/kg/day root ethanolic extract(WSRE) respectively,T3, T4 received 1,2 g/kg diet rootpowder(WSRP) respectively.Results revealed significant increase in Hb and PCV % in quails supplemented with T4at 10 and 15weeks of age, and in T3 and T4 groups at 12 weeks of age in comparison with T0and WSRE groups. At 10 and 15 weeks old, T2 resulted in significant increasing inHeterophil/Lymphocyte ratio in comparison withT0and other treatments. At 15 weeks ofage,T1and T2 significantly increased Heterophil% in comparison with T0 and WSRP groups,while, quails in T4 showed significant reduction in Heterophil% and significant increasing inLymphocyte% compared with T1, also results showed that supplementing quails with T4significantly increased serum iron .Thyroid hormones didn’t affected significantly due totreatments while T3 significantly increased TSH.

الخلاصة:من خلال تأثیرھا Withania somnifera أجریت الدراسة بھدف اختبار الفعالیة المضادة للاجھاد لجذور نبات27 °م). -37- في بعضصفات الدم الفسلجیة لطائر السلوى الیاباني المربى تحت درجات حرارة بیئیة مرتفعة( 27مجموعة غیر T استخدم في ھذه الدراسة 300 طائر انثى وزعت عشوائیا على خمس معاملات وكما یلي: 0مجموعتي المعاملة بالمستخلص الكحولي للنبات وبجرعتي 50 و 100 ملغم/كغم/یوم وعلى التوالي T و 2 T معاملة(سیطرة) و 1مجموعتي المعاملة الیومیة بالمسحوق وبمستوى اضافة 1 و 2 غم/كغم علف على التوالي. T و 4 T و 3في الاسبوعین T لدى الطیور المعاملة 4 (%PCV) و (Hb) أظھرت النتائج حصول زیادة معنویة في كل منعند عمر 12 أسبوع بالمقارنة مع السیطرة ومجموعتي المستخلص. بینت T و 4 T 10 و 15 من العمر ولدى طیور المعاملة 3قد ادت الى زیادة معنویة في نسبة الھتروفیل/اللمفوسایت بالمقارنة مع T نتائج الاسبوعین 10 و 15 ایضا بأن المعاملة 2السیطرة وبقیة المعاملات كما أدت المعاملة بالمستخلص الكحولي الى حصول زیادة معنویة في النسبة المئویة لخلایاالى حصول T الھتروفیل عند عمر 15 أسبوع بالمقارنة مع السیطرة ومجموعتي المسحوق، في حین ادت المعاملة 4وبینت النتائج ایضا ان المستوى الاعلى T انخفاضمعنوي في الھتروفیل% وزیادة معنویة في اللمفوسایت% بالمقارنة مع 1قد ادى الى زیادة معنویة في حدید مصل الدم ولم تتأثر معنویا مستوى ھرمونات الدرقیة (T من مسحوق جذور النبات( 4.TSH قد ادت الى حصول زیادة معنویة في T نتیجة المعاملات المختلفة في حین ان


Article
The Effect of Incorporation of Two Different Fibers on Some Mechanical Properties of Heat Cure Acrylic Resin Dr. Abdalbasit A Fatihallah BDS, MSc, PhD

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Abstract

To evaluate the effect of addition of different fibers on some mechanicalproperties of heat cured acrylic resin (flexural strength, impact strength and hardness).210 specimens were used in the study.70 specimens were used for flexuralstrength with measurements (65mm*10mm*2.5mm) length, width and thicknessrespectively. The specimens were divided into seven test groups (n=10). The firstgroup is the Control one and it was without fiber reinforcement, second groupreinforced with 2mm polyester fibers, third group reinforced with 4mm polyesterfibers, fourth group reinforced with 2mm Polypropylene fibers, fifth group reinforcedwith 4mm Polypropylene fibers, sixth group reinforced with 2mm of both fibers(polyester and Polypropylene), and seventh group reinforced with 4mm of both fibers(polyester and Polypropylene). 70 specimens were used for impact strength in sevengroup (n=10) with measurements (80mm*10mm*4mm) length, width and thicknessrespectively. 70 specimens were used for hardness test in seven groups (n=10) withmeasurements (65mm*10mm*2.5mm) length, width and thickness respectively.The Results Show that there are highly significant differences between all groupsexcept for a significant differences between control and combination 2 mm fiberlength (mean differences=33.45). For the hardness test the comparisons show thatthere is no significant differences between groups except for a significant differencesbetween control and combination of both fibers with 2mm length (mean differences=-1.34). For impact strength; there are highly significant differences between all groupsexcept for a significant differences between Polyester fiber of 2mm length andcombination of the two fiber of 2 mm length (mean differences=-3.1).In conclusion, the addition of different fibers (polyester and Polypropylene) toacrylic resin gives it more resistance to break and more resistance to bend.


Article
Evaluation of Transverse strength, Impact strength and Hardness of Thermosense denture base material and compare the result with heat cure acrylic denture base material (in vitro study)

Author: Dr. Hadeel Adnan Mohsin, B.D.S., M.Sc. * د. هديل عدنان
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2016 Volume: 13 Issue: 1 Pages: 64-69
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background: Thermosense material is the innovative virtually unbreakable, newmonomer free rigid denture base material easy and quick to polish and availablein 10 colors, suitable to patients unable to accept denture made from materialsthat could result in allergic reactions or other sensitivity problems. This type issuitable for full and partial denture and can be used for rebase and reline jobs.Also suitable for overdenture on implant and for repair.Material and methods: sixty samples were prepared and divided in to two maingroups according to the type of material that used (thermosense denture basematerial and heat cure acrylic denture base material). Each main group weresubdivided in to three subgroups according to the type of test that has used(Hardness, impact strength, and transverse strength). Data were analyzed by onewayanalysis of t-test.Results: for this study the result for three tests; hardness, transverse strength andimpact strength show high significant difference.conclusion: This study showed Thermosense denture base material had higher impactstrength than Heat cure acrylic denture base material but this material had highertransverse strength and hardness than Thermosense denture base material.


Article
The Effect of Heat Treatment onElastic-PlasticBehaviorand Absorbing Energy for L-shaped Mild Steel Under CompressiveAxialLoad-ENG
تأثير المعاملة الحرارية على سلوك المرونة- اللدونة و امتصاص الطاقة لصفائح الفولاذ على شكل L تحت قوى انضغاطية محورية

Author: Ayad Arab Ghaidan أياد عرب غيدان
Journal: AL Rafdain Engineering Journal مجلة هندسة الرافدين ISSN: 18130526 Year: 2013 Volume: 21 Issue: 5 Pages: 115-126
Publisher: Mosul University جامعة الموصل

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Abstract

AbstractThe paper deals with the experimental investigation to crushing collapse behaviour of thin-walled mild steel L-shaped structural under compressive axial load. The aim of this paper is to show that the increase of plastic region will be on the account of elastic region for L-steel plates under compressive axial load by using heat treatment (Tempering). The result has shown a decrease in elastic region withan increase in plastic region during crushing L- steel plates which caused an increase in absorbing energy. Details of the deformation processes were examined by using theoretical, experimental andthree-dimensional finite element models. The effect of heat treatment processes were presented to increase plastic region with absorbing energy during crushing plates, Heat treatment is a very useful process to improve absorbing energy with decreasing size of plates. Static load-deformation curves were compared with those obtained from theoretical model based on perfect plasticity and finite element simulations using nonlinear ANSYS program and obtained by quasi-static tests. Conclusions have been given concerning the agreement between the results of finite element simulations and the static once.Keywords: Heat treatment processes, Axial crushing, ANSYS, L-shape plate, Finiteelement.

الخلاصةيتعامل هذا البحث مع التجارب العملية لسلوك انهيار فولاذ على شكل حرف (L) تحت قوة انظغاطية محورية. تم مناقشة النتائج باستخدام نماذجَ عناصرِ محددة ثلاثية الأبعادِ وتجريبيةِ ونظريةِ. تم دراسة تأثير معاملة الحرارة على منطقة اللدونة و تاثيرها على امتصاص الطاقة اثناء السحق لصفائح ألفولاذ و تبين ان المعاملة الحرارية مفيدة جدا لتحسين الطاقة الممتصة عند تقليل ابعاد النموذج. تم مقارنة منحنيات القوى و التشويه اثناء السحق للنتائج المستحصلة من التجارب العملية و النظرية و العناصر المحددة من برنامج انسس حيث بينت الاستنتاجات ان هنالك تقارب بين النتائج العملية و النتائج التي تم الحصول عليها من استخدام العناصر المحددة.


Article
Push-out bond strength and apical microleakage of (MTA Plus, Biodentine, and Bioceramic) as apical third filling (An in vitro study)

Authors: Dr. Abeer A. Abass B.D.S. د. عبير عباس --- Prof. Dr. Jamal A. Mehdi B.D.S., M.Sc. دز جمال عزيزىمهدي
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2016 Volume: 13 Issue: 1 Pages: 1-10
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background: This study was conducted to evaluate the sealing ability of (MTA Plus,Biodentine Bioceramic root repair material) as an apical third filling by using(Push-out bond strength test, apical microleakage test).Materials and methods: Sixty straight palatal roots of the maxillary first molars teethwere used in this study, the roots were instrumented by using crown downtechnique with Protaper universal rotary system, the roots were randomly dividedinto three groups according to the materials used for filling apical third(n=20).Group (1): MTA Plus . Group (2): Biodentine. Group (3): Bioceramicrepair material. For all groups complete obturation with easy & quick obturationsystem was used. After incubation period of three days ten roots for each groupwere embedded in clear acrylic resin and each root sectioned in apical to provideslice 2mm in thickness. The bond strength was measured using computerizeduniversal testing machine. Ten roots remain from each group used for apicalmicroleakage study. The roots submerged in 2% methylene blue for three days.The roots were cleared and the degree of linear dye penetration was measured inmillimeter by stereomicroscope under 40 X magnification with calibrated scaleocular grid. The data were analyzed statistically using ANOVA and LSD test.Results: In push-out bond strength showed the Biodentine has the highest meanvalues (19.687) in comparison with other groups followed by MTA Plus groupwhich the mean value was (19.395), while the BC material group has the lowestmean value (10.977). In microleakage the BC material group has the high meanvalues (0.477) of apical dye penetration in comparison with other groups.Biodentine group has lowest mean values (0.359) of apical dye penetration.Conclusions: The Biodentine higher push-out bond strength and less apicalmicroleakage then other test materials.

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