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Microfiltration Membranes for Separating Oil / Water Emulsion

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This research was aimed to study the efficiency of microfiltration membranes for the treatment of oily wastewater and the factors affecting the performance of the microfiltration membranes experimental work were includes operating the microfiltration process using polypropylene membrane (1 micron) and ceramic membrane (0.5 micron) constructed as candle; two methods of operation were examined: dead end and cross flow. The oil emulsion was prepared using two types of oils: vegetable oil and motor oil (classic oil 20W-50). The operating parameters studied are: feed oil concentration 50 – 800 mg/l, feed flow rate 10 – 40 l/h, and temperature 30 – 50 oC, for dead end and cross flow microfiltration. It was found that water flux decreases with increasing operating time and feed oil concentration and increases with increasing operating temperature, feed flow rate and pore size of membrane. Also, it was found that rejection percentage of oil increases with increasing flow rate and rejection percentage decreases with increasing time, feed oil concentration, feed temperature and pore size of membrane for dead end and cross flow microfiltration. In cross flow microfiltration, reject concentration (concentrate) increases with increasing flow rate, feed concentration, time and feed temperature. The dead end filter has more flux compared to cross flow filter, while, in cross flow the oil rejection percentage is best than dead end. Flux for vegetable oil is more than motor oil but rejection percentage for vegetable oil is less than that for motor oil. The highest recovery ratio was found is 44.8% for cross flow process with recirculation of concentrating stream to feed vessel. The highest rejection percentage of oil was found is 98 % and 97.8 % for cross flow and dead ends respectively.


Article
Studying the Effect of Addition of Carbon Black on Rheological Properties of Polypropylene and Polycarbonate
دراسة تأثير إضافة الكاربون الاسود على الخواص الانسيابية لبولي بروبيلين والبولي كاربونات

Authors: Najat J. Salah --- Abbas A. Jawad
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2013 Volume: 31 Issue: 5 Part (A) Engineering Pages: 976-991
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In the present research the rheological properties of polymer melt composed of (polypropylene- polycarbonate ) unfilled_ filled with different amounts of Iraqi carbon black (2 – 7) wt% was studied. Single screw extruder was used for development of these blends . The rheological behaviour of these blends was investigated by using rotational concentric type rheometer . The rheological properties shear rate( ( , apparent viscosity (a), dynamic viscosity(ή ), shear stress (τ) and angular frequency (ω),shearing flow at various temperatures ( 220 ˚C, 240˚C and 260 ˚C) were studied and found to be increase with increasing the amount of filler and decrease with increasing temperature. The flow curves were determined in the range of shear rate from about (10 to10 2 ) s-1. The activation energy was also measured, the values of activation energy varied from(11.939 to 20.892) KJ/Mole for different formation.

في هذا البحث تم تحضير منصهر بوليمري من بولي برولين وبولي كاربونات المدعمة بنسب وزنيه مختلفة من الكاربون الاسود(السخام) العراقي (2 – 7)% باستخدام جهاز الباثقة الأحادية. وبعد ذلك جرت دراسة الخواص الانسيابية باستخدام جهاز لقياس الانسيابية ثنائي المركز. تم التوصل الى ان الخصائص الانسيابية التي تم دراستها في تدفق القص والمتضمنة معدل القص (( , اللزوجة الظاهرية (ha) ، اللزوجة الديناميكية (ή) ، إجهاد القص (τ) والتردد الزاوي (ω) ، كانت متذبذبة في درجات حرارة المختلفة ( 220 ˚C, 240˚C and 260 ˚C) حيث تزداد بزيادة كميه الماده المدعمه وتقل مع زيادة درجه الحرارة وتم تحديد منحنيات التدفق في نطاق معدل القص من حوالي( 10 إلى 2 ( 10 لكل ثانيه فضلا عن طاقة التنشيط تفاوتت من (11.939 إلى25.368) كيلو جول /مول للخلطات المختلفة.


Article
Mechanical Properties of High Performance Fiber Reinforced Concrete
الخواص الميكانيكية للخرسانة العالية الاداء المسلحة بألالياف

Authors: Wasan Ismail Khalil --- Ikbal Naeem Gorgis --- Zeinab Raad Mahdi
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2013 Volume: 31 Issue: 7 Part (A) Engineering Pages: 1365-1387
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

An experimental work was carried out to produce high performance concrete (HPC) using superplasticizer and silica fume reinforced with fiber. The variables studied were fibers type (steel fibers and polypropylene fibers), aspect ratio of steel fibers (60 and 100) and fiber volume fraction (0.0%, 0.5%, and 0.75%). The effect of fibers on the mechanical properties (compressive strength, splitting tensile and flexural strength, static modulus of elasticity, toughness, and resilience) of normal strength and high performance concrete was also studied. The results show that the optimum dosage of silica fume is 5% as addition by weight of cement with superplasticizer dosage 2 liter/100kg of cement. This dosage of silica fume improves the compressive strength of concrete by about 25% relative to concrete mix without silica fume. The addition of steel fibers causes a slight increase in compressive strength of HPC as fiber volume fraction increases, while the compressive strength decreases as fiber aspect ratio increases. Both splitting tensile and flexural strengths show a significant increase as the fiber volume fraction and aspect ratio increases. The percentage increase in compressive, splitting tensile and flexural strengths for HPC with steel fiber volume fraction 0.75% and aspect ratio 100 at age 60 days is about 9%, 75%, 64%, while for HPC containing polypropylene fiber with volume fraction 0.5% is about 8.5%, 2%, 0% respectively relative to non fibrous HPC.

يشمل البحث دراسة الخواص الميكانيكية للخرسانة العالية الاداء المسلحة بألالياف. يتضمن البرنامج العملي انتاج خرسانة عالية الاداء بأستخدام الملدن المتفوق وابخرة السيلكا المكثفة والمسلحة بالالياف. المتغيرات التي تم دراستها هي نوع الالياف (الالياف الفولاذية والياف البولي بروبلين) , النسبة الباعية للالياف الفولاذية (60, 100) والنسبة الحجمية للالياف (0%, 0,5%, 0,75%). تم دراسة تأثير اضافة الالياف على الخواص الميكانيكية (مقاومة الانضغاط, مقاومة الشد الانشطاري, مقاومة الانثناء, معامل المرونة الستاتيكي, الصلابة, الرجوعية) للخرسانة الاعتيادية والعالية الاداء. اظهرت النتائج ان الوزمة المثالية لابخرة السيلكا المكثفة كانت 5% كأضافة من وزن الاسمنت والوزمة المثالية للملدن المتفوق هي 2لتر لكل 100 كغم من الاسمنت . الوزمة لابخرة السيلكا المكثفة ساعدت في تطوير مقاومة الانضغاط للخرسانة حوالي 25% بالمقارنة مع الخلطة الخرسانة بدون ابخرة السيلكا.بينت النتائج ان اضافة الالياف الفولاذية تسبب زيادة طفيفة في مقاومة الانضغاط للخرسانة عالية الاداء عند زيادة النسبة الحجمية للالياف, بينما تقل مقاومة الانضغاط بزيادة النسبة الباعية للالياف. كذلك تبين بأن مقاومة الشد الانشطاري ومقاومة الانثناء تزداد بشكل واضح بزيادة النسبة الحجمية والنسبة الباعية للالياف. حيث كانت نسبة الزيادة في مقاومةالانضغاط والشد الانشطاري ومقاومة الانثناء للخرسانة عالية الاداء الحاوية على نسبة حجمية 0,75% ونسبة باعية 100 بعمر 60 يوم حوالي 9% و 75% و 64% اما بالنسبة للخرسانة عالية الاداء الحاوية على الياف البولي بروبلين بنسبة حجمية 0,5% فكانت نسبة الزيادة 8,5%و2% و0% على التوالي بالمقارنة مع الخرسانة عالية الاداءغير حاوية على الياف.


Article
The effect of addition of untreated and oxygen plasma treated polypropylene fibers on some properties of heat cured acrylic resin

Authors: Waffaa I. Mohammed --- Intisar J. Ismail
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 4 Pages: 33-38
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The polymethyl methacrylate is the most reliable material for the construction of complete and partialdentures, despite satisfying esthetic demand itsuffered from having unsatisfactory properties like impact strength andtransverse strength.This study was designed to improve the impact strength and transverse strength of heat cure acrylic resin by addinguntreated and oxygen plasma treated polypropylene fibers and investigate the effect of this additive on someproperties of acrylic resin materials.Materials and methods: Untreated and oxygen plasma treated polypropylene fibers was added to PMMA powderby weight 2.5 %. Specimens were constructed and divided into 5 groups according to the using tests; each groupwas subdivided in to 3 subgroups. The tests conducted were impact strength, transverse strength, surface hardness,surface roughness, water sorption and solubility. Data were analyzed by one way analysis of variance (ANOVA) andleast significant differences (LSD).Results: After incorporation of untreated and oxygen plasma treated polypropylene fibers there was a highlysignificant increase in impact strength and surface hardness; while there was a non significant difference intransverse strength. Also the value of water sorption increase significantly but with the limit of ADA specification.Conclusion:Within the limit of this study it can be concluded that the reinforcement with polypropylene fiberseffective method to increase fracture resistance of denture base; while reinforcement with oxygen plasma treatedpolypropylene fibers further increase fracture resistance


Article
Influence of Poypropylene Fibers on the Soil Stabilization
تأثير ألياف البولي بروبلين على تثبيت التربة

Author: Heba Dawood Salim
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2013 Volume: 31 Issue: 20 Part (A) Engineering Pages: 316-323
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this paper the polypropylene fiber was chosen as the additive material to know how it is effect on the soil stabilization, which it is used as additive for concret mixture; the polypropylene fiber is inert material and does not interact with water. The paper studies the addition of this material to a silty clay soil and its effect on the consistency limits, shear strength and compaction of the blended materials. The results show that there is an improvement in the shear strength only when the addition of the rate 1% and 2%from soil weight; either the effective of the consistency limit it was increasing the water content with increasing the rate of the addition material, because it have drink of water. At the compaction test it was founded that the increasing in dry density at the addition of 1% and 2% and reducing its value at the addition of 3% with increasing of water optimization.

في هذا البحث، تم اختيار ألياف البولي بروبيلين كمادة مضافة لمعرفة تأثيره على تأثير على تثبيت التربة، والتي تستخدم كمضاف لخليط الخرسانة، وألياف البولي بروبلين هي مادة خاملة لا تتفاعل مع الماء. يدرس البحث إضافة هذه المادة إلى التربة الطينية الغرينية وأثرها على حدود القوام، قوة القص والرص للمواد المخلوطة. وتظهر النتائج أن هناك تحسنا في قوة القص فقط عند إضافة نسبة 1٪ و 2٪ من وزن التربة؛ إما حدود القوام الفعالة تعمل على زيادة محتوى الماء مع زيادة نسبة المواد بسبب شرب الماء. في اختبار الرص، وجدت زيادة في الكثافة الجافة عند إضافة 1٪ و 2٪ و تقل قيمتها عند إضافة 3٪ مع الزيادة المثلى للمياه.


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
RHEOLOGICAL PROPERTIES OF VACUUM GAS OIL – POLYPROPYLENE BLENDS SYSTEM
خصائص الجريان لمزيج زيت الغاز مع البولي بروبلين

Authors: S. R. Sultan --- Adnan A. Abdul Razak --- A. M. Hameed
Journal: DIYALA JOURNAL OF ENGINEERING SCIENCES مجلة ديالى للعلوم الهندسية ISSN: 19998716/26166909 Year: 2015 Volume: 8 Issue: 4 Pages: 804-812
Publisher: Diyala University جامعة ديالى

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Abstract

The present work is concerned with study of the flow behavior of poly propylene (PP) and Vacuum Gas Oil (VGO) blends. Viscosimetry measurements of the blends with different polymer weight fractions between 0 and 10 wt%., temperatures between 391 K and 491 K at shear rates up to 1000 S-1 were performed. These blends were shown to have peculiar flow behavior exhibiting Newtonian fluid flow property at higher temperatures and lower polymer concentrations, while at lower temperatures and at higher polymer concentrations, showing non-Newtonian shear thinning or pseudo-plastic behavior. These properties have been shown to be more pronounced at lower shear rates than at higher shear rates. The application of Ostwald-De Waele power law model for the prediction of the viscosity under different operating conditions of shear rates, temperature and base components weight fractions has been given a good fit for the experimental viscosimetry data.

في هذا البحث تم دراسة سلوك الجريان لمزيج من زيت الغاز والبولي بروبلين , حيث تم قياس اللزوجة للمزيج عند نسب مختلفة من البوليمر تتراوح بين (0-10)% ودرجات حرارة تتراوح بين 391 الى 491 كلفن وبمعدلات قص اعلى من 1000 ثانية-1 . اثبتت النتائج لهذا المزيج سلوك تدفق نيوتيني عند ارتفاع درجات الحرارة وتراكيز قليلة للبوليمر في حين , عند درجات الحرارة المنخفضة ويتراكز اعلى للبوليمر يكون السلوك غير نيوتيني, حيث تكون هذة الخصائص اكثر وضوحاً في انخفاض معدلات القص. تم تطبيق نموذج Ostwald-De Waele power law للتنبؤ بلزوجة المزيج في ضروف تشغيل مختلفة من معدلات قص ودرجة حرارة ونسبة البوليمر حيث اعطت النتائج تطابق جيد مع النتائج العملية.


Article
Evaluation of the Effect of silanized Zirconium Oxide nano-fillers and Plasma Treated polypropylene fibers Addition on some Properties of Heat Cured Acrylic Resin Denture Base Material

Author: Dr. Noor Falah Abdul-Hadi, B.D.S., M.Sc. * د.نور فلاح عبدالهادي
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2016 Volume: 13 Issue: 1 Pages: 70-76
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background: The polymethylmethacrylate is the most reliable material for theconstruction of dentures but it has the disadvantages of lacking strength andradio-opacity. The purpose of this study was to evaluate the effect of addition ofmodified nano-zirconium oxide (zro2 ) and plasma treated polypropylene fiberson some mechanical properties of heat cure acrylic resin materials.Materials and methods:- Zirconium oxide nanoparticles were coated with a layer ofpropyltrioxysilane before dispersed and sonicated in monomer(MMA)inpercentage of 2% by weight . The plasma treated polypropylene fibers were inpercentage of 2% by weight added to polymer powder. Sixty specimens wereconstructed and divided into 3 groups according to the using tests; each groupwas subdivided into two subgroups. The tests used were impact strength,transverse strength and surface hardness. Data were analyzed T-test.Results:- After the addition of plasma treated polypropylene fibers and modifiednano-Zro2 fillers there was a highly significant increase in impact strength,transverse strength and surface hardness.Conclusion: It can be concluded that the addition of modified nano-Zro2 fillers andplasma treated polypropylene fibers effective method to enhance the fractureresistance of acrylic denture base material.


Article
Effect of Adding Polypropylene Fiber on The Behavior of Saline Soil under Washing and soaking
تأثير اضافة مادة بولي بروبيلين على التربة السبخة وسلوكها اثناء غمرها وغسلها بالماء

Author: Saleem Mahmood Imariq سليم محمود معارك
Journal: Wasit Journal of Engineering Sciences مجلة واسط للعلوم الهندسية ISSN: 23056932 Year: 2015 Volume: 3 Issue: 1 Pages: 30-39
Publisher: Wassit University جامعة واسط

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Abstract

Saline soil is a soil rich with salt resulting from evaporation of irrigation water. This soil has good engineering properties when dry, but once is wetted it loses its entire structure (collapse) and undergoes very large instantaneous settlement. The soil is brought from Al-Dalmaj district. A square footing 50mm×50mm made of steel is used. The stress is applied from a fixed loading system designed especially for model tests. In this study effect of adding Polypropylene fiber as percentage 1%,3% by weight on behavior of saline soil at the same loading level was investigated and shows improving in results in collapsibility of soil by percent 62% in percent adding 1%.

التربة المالحة هي التربة الغنية بالملح التي تنتج عن تبخر مياه الري. هذه التربة لها خصائص هندسية جيدة عندما تجف، ولكن بمجرد تعرضها للبلل فإنها تفقد هيكلها (انهيار) ويحصل فيها هبوط فوري كبير جدا. تم جلب التربة من منطقة الدلمج وأستخدم اساس مربع بأبعاد 50×50 مم وضعت بقالب من الصلب. حيث يتم تطبيق الضغط من نظام تحميل ثابت صمم خصيصا لاختبارات نموذجية. في هذه الدراسة، قمنا بدراسة تأثير إضافة الألياف مادة البولي بروبيلين كنسبة مئوية 1٪، 3٪ وزنا على سلوك التربة المالحة على نفس مستوى التحميل وتظهر في نتائج تحسين انهياريه التربة من 62٪ الى 1٪


Article
Evaluation the Effect of Addition of Plasma Treated Polypropylene Fiber and Silanized Silicon Dioxide Nanoparticles Composite on Some Properties of Heat-Polymerized Polymethylmethacrylate

Authors: Ahmed G. Ahmed احمد غيث احمد --- Intisar J. Ismail انتصار جميل اسماعيل
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 4 Pages: 1-8
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Polymethylmethacrylate (PMMA) is the most commonly used material in denture construction. This material is far from ideal in fulfilling the mechanical requirements, like low impact and transverse strength and poor thermal conductivity are present in this material.The purpose of this study was to study the effect of addition a composite which include 1%wt silanized silicone dioxide nano fillers (SiO2) and 1wt% oxygen plasma treated polypropylene fiber (PP) on some properties of heat cured acrylic resin denture base material (PMMA).Materials and methods: One hundred (100) prepared specimens were divided into five groups according to the tests, each group consisted of 20 specimens and these were subdivided into two groups (unreinforced heat cured acrylic resin as control group)and reinforced acrylic resin with ( 1%wt Nano SiO2 and 1% wt oxygen plasma treated polypropylene fibers) group. The transverse strength¸ impact strength, indentation hardness (shoreD), surface roughness and water sorption and solubility were investigated. The results were statistically analyzed using descriptive and t-test.Results: The results of this study show that a highly significant increase in impact strength (10.4939 Kj/m2),surface hardness (89.9375) surface roughness (0.9498) and water sorption (0.0171mg/cm2) was observed with the addition of 1%wt silanized (SiO2) nanoparticles and 1%wt oxygen plasma treated polypropylene fibers to (PMMA) , also significant decrease in transverse strength (103.4753 N/mm2), nonsignificant decrease occurred in water solubility which was (0.0005mg/cm2).Conclusion: The incorporation of 1%wt silanized SiO2 nanoparticles and 1%wt oxygen plasma treated polypropylene fiber to heat cure PMMA form a composite improves the impact strength, surface hardness and surface roughness of acrylic resin, at the same time this addition increase the water sorption and decrease water solubility; while significant decrease in transverse strength

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