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Article
Design Of A solar Dryer Provided With Back And Heating systems And Its Testing In The Drying Of Fishes And meats
تصميم مجفف شمسي مزود بمنظومتي الراجع والتسخين واختباره في تجفيف الاسماك واللحوم

Author: Asaad R. AL-Hilphy Ghyath.H.majeed
Journal: Journal of Basrah Researches (Sciences) مجلة ابحاث البصرة ( العلميات) ISSN: 18172695 Year: 2007 Volume: 33 Issue: 3B Pages: 20-30
Publisher: Basrah University جامعة البصرة

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Abstract

A solar dryer was designed for fish and meat drying . Its consist of solar collector with ribbed absorbent plate , its dimensions 1*0.5 m2 and drying chamber contains ten beds , plastic pipe that humid air carry to the head of solar collector and small kerosene cooker under drying chamber .The results showed that the solar dryer enable usage in the winter and summer semesters, rainy and cloudy days for drying fishes and meats .The consumption time to drying , drying efficiency , rate of dehydration , drying rate and mean of humidity reducing higher than usage of natural sun drying . And showed the results the drying rate for fish and meat was multi stage for two methods of drying, exception dried fish by natural sun drying. .

تم تصميم مجفف شمسي للاسماك واللحوم سعته 25 كغم يتكون من مجمع شمسي ذي صفيحة امتصاص مضلعة ابعادها 0.5*1 م وغرفة تجفيف تحتوي على عشرة اطباق وانبوب بلاستيكي ينقل الهواء المحمل بالرطوبة الى مقدمة المجمع الشمسي وطباخ نفطي صغير اسفل غرفة التجفيف .اظهرت النتائج امكانية استعمال المجفف الشمسي في فصلي الصيف والشتاء وكذلك في الايام الغائمة والممطرة في تجفيف الاسماك واللحوم . كما ان الزمن المستغرق للتجفيف وكفاءة التجفيف ونسبة استرجاع الماء ومعدل التجفيف ومعدل انخفاض الرطوبة باستعمال ذلك المجفف الشمسي كانت اعلى من تلك عند استعمال التجفيف الشمسي الطبيعي .كما بينت النتائج ان معدل التجفيف للسمك واللحم كان من نوع متعدد المراحل ولكلا طريقتي التجفيف ماعدا السمك في حالة التجفيف الشمسي الطبيعي.


Article
Evaluation of Some Properties of Iraqi Plaster by Using Some Additives and Microwave Drying Technique

Author: Dr. Areej Shehab Ahmad. (Lecturer), M.Sc. in Prosthodontics د. اريج شهاب احمد
Journal: MUSTANSIRIA DENTAL JOURNAL مجلة المستنصرية لطب الاسنان ISSN: 18138500 Year: 2015 Volume: 12 Issue: 1 Pages: 39-52
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Aims of this study:1- Evaluation of some properties of Iraqi plaster, compressivestrength & surface roughness. 2- Improving the quality of Iraqi plaster byincorporation of some additives. 3- Studying the effect of microwave drying onthe compressive strength & surface roughness of Iraqi plaster.Methods: 56 samples of Iraqi plaster used in this study, divided into two main groupsaccording to the main tests used, 28 samples for compressive strength & 28samples for surface roughness.Samples of each test were divided into two groups (each group 14 samples).The first group was without additives, while the second includes the modifiedgypsum products (Iraqi plaster) with additives, (Gum Arabic 0.5%, calcium oxide0.75%, and ferric oxide 0.2%).Samples of each subgroup are subdivided into two subgroups also according tothe drying method of Iraqi plaster, Open air drying method & Microwave dryingmethod (7 samples for each)Measuring of both tests was done in Technology University in Baghdad.Compressive strength measurement by using (unconfined compression machine),while, surface roughness of the samples was measured by Profilometer.Results: The results showed that incorporation of additives to Iraqi plaster result inchanging their evaluated properties & Comparing with open air drying method,microwave drying enhanced the properties tested in this study.Conclusions: incorporation of additives to Iraqi plasters result in (Improvement of thecompressive strength, reduction of the surface roughness and increasesmoothness).


Article
Effect of Wetting and Drying Cycles on Behavior of Concrete Externally Strengthened with CFRP Laminates

Authors: D.H. Mohammed --- T.S. Al-Attar --- H.A. Dawood
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2017 Volume: 35 Issue: 7 Part (A) Engineering Pages: 675-684
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This study describes an experimental work that was made to evaluate the effect of wetting and drying cycles on the behavior of concrete specimens externally strengthened with CFRP laminates. The experimental work included testing of twenty-three concrete specimens externally strengthened with CFRP laminates in different positions, with two compressive strength levels. The experimental variables considered in the test program include, compression strength of concrete, number of carbon fiber reinforced polymer (CFRP) strip layers, using CFRP strips throughout the total length of the specimen or within the middle third, and the number of wetting and drying cycles. The testing program included compression strength test, four-point flexural test, direct tension test, single and double face shear tests. The experimental results show that the increasing time of exposure to wetting and drying cycles lead to a significant increase in compressive strength, increasing the cracking loads which reached up to 22%., and decreasing the ultimate load carrying capacity.


Article
Effect of Feed Concentration on the Production of PregelatinizedStarch in a Double Drum Dryer

Author: Riyadh S. Al-Mukhtar
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2007 Volume: 8 Issue: 4 Pages: 13-17
Publisher: Baghdad University جامعة بغداد

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Abstract

Double drum dryer is operated for producing pregelatinized maize starches using feed starch slurries of different solids(7, 10 and13 g/100 g )content . Steam pressure (2,3,and 4 bar), the level of pool between the drums (4,7,and 10cm) , and speed of drums rotation (3,4,and 6 rpm) are varied together with the feed solids content in a practical range of values. The response of the dryer is registered by measuring several output variables, i.e. external drum temperature,product moisture content, mass flow rate.


Article
The effects of drying techniques on the compr-essive strength of gypsum products

Authors: Radhwan H Hasan --- Kasim A Mohammad
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2005 Volume: 5 Issue: 1 Pages: 63-68
Publisher: Mosul University جامعة الموصل

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Abstract

Excess water in set dental stone decreases its strength.So different methods were used to expel excess water but thecompressive strength may be affected by drying technique.The purpose of this study was to evaluate the compressive strengthof two types of set dental stone after air, conventionaloven and microwave drying techniques.A total of 60 stone specimens (30 specimens made fromSilky Rock stone and 30 Zeta stone) were prepared by the aidof an acrylic split mold according to ADA Specification No.25. Specimens were divided into six groups of 10 identicalspecimens for each. Then groups were either dried by air,conventional oven or microwave oven. Using UnconfinedCompression Machine, the specimens were loaded by a crosshead speed of 1 mm/minute till the specimen being fractured.The load required to fracture the stone specimens was recordedand analyzed using analysis of variance followed by Duncan’sMultiple Range Test for the statistical comparisons betweendrying techniques at a significance level of p< 0.05, andStudent’s t–test was used to compare between the two stonetypes.The results revealed that high significant differenceswere present between the different drying techniques(p<0.0001) with air dried specimens were significantly strongerthan others and microwave dried specimens were significantlystronger than conventional oven dried specimens. SilkyRock (type IV) stone was significantly stronger than Zeta(type III) stone (p<0.001).From this study, it could be concluded that the highestcompressive strength can be obtained by air drying of the stonefor 24 hours, while microwave drying technique give betterresults than conventional oven drying technique with theadvantage of time saving over the two other drying techniques.


Article
Computer Aided Design for Spray Driers

Authors: Adil A. Al-Hemiri عادل احمد الحميري --- Saad N. Saleh
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2007 Volume: 8 Issue: 1 Pages: 27-34
Publisher: Baghdad University جامعة بغداد

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Abstract

The aim of this work is to develop an axi-symmetric two dimensional model based on a coupled simplified Computational Fluid Dynamic (CFD) and Lagrangian method to predict the air flow patterns and drying of particles. Then using this predictive tool to design more efficient spray dryers. The approach to this is to model what particles experience in the drying chamber with respect to air temperature and humidity. These histories can be obtained by combining the particles' trajectories with the air temperature / humidity pattern in the spray dryer. Results are presented and discussed in terms of the air velocity, temperature, and humidity profiles within the chambers and compared for drying of a 42.5% solids solution in a spray chamber 2.22 m in diameter with a cylindrical top section 2.00 m high and a bottom cone section 1.725 m high.


Article
Spray-dried liposomes: A study of the effect of carbohydrate carrier and concentrations on liposome size and drug entrapment

Author: Nozad Rashid Hussein
Journal: Zanco Journal of Medical Sciences مجلة زانكو للعلوم الطبية ISSN: 19955588/19955596 Year: 2019 Volume: 23 Issue: 3 Pages: 345-353
Publisher: Hawler Medical Univeristy جامعة هولير الطبية

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Abstract

Background and objective: Dry powder inhalation provide many promising features for drug delivery to the pulmonary system, such as localization of drug within the lungs, drug retention in the respiratory tract, and reduced systemic toxicities. This study aimed to prepare dry powders of liposomes containing salbutamol sulfate using spray drying and study the influence of carrier type and concentration on liposome size and drug entrapment following rehydration of liposomal powder.Methods: Ethanol based proliposomes technique was used to generate liposomes containing salbutamol sulfate. Carbohydrate carriers: lactose, trehalose, sucrose, and mannitol in 1:6 or 1:10 (w/w) lipid to carrier ratio were separately incorporated into liposome formulations and dried by Büchi Mini-SprayDryerB-290. The protective effects of the sugars were investigated in terms of product yield (%), volume median diameter and size distribution of liposomes and entrapment efficiency of the drug.Results: The product yield (%) of spray dried liposome formulations with carriers was in the following order; trehalose (94.02 ± 1.20%) > sucrose (69.91 ± 1.75%) > lactose (68.30 ± 1.14%) > mannitol (50.16±0.80%) for the 1:6 formulations. Depending on the carrier type and lipidto carrier ratio, the vesicle size of liposomes with lactose and mannitol increased significantly (P <0.0001 and P = 0.0027, respectively), while the vesicle size with trehalose and sucrose varied to a lesser extent (P >0.05) compared to the control formulations (3.6µm ±0.24). For 1:10formulation, the vesicle size with mannitol (P <0.001) and sucrose (P <0.001) increased significantly. The drug entrapment efficiency using the 1:6 formulations was 20.74±1.78% for sucrose, 35.59±2.42% for trehalose, 67.21±1.89 % for lactose, and 80.84±3.64% for mannitol.Conclusion: Stable spray-dried liposomes were manufactured using sugars as carriers. The findings of this study have demonstrated the potential using of carbohydrate carriers to increase the physical stability of liposomes during the drying process, and trehalose can offer formulations with most desirable characteristics, while mannitol showed the least benefits.


Article
Heat and Mass Transfer During Air Drying of Sweet Potato

Authors: Shaimaa Mohammed Ameen --- Manal H. AL-Hafidh
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2009 Volume: 15 Issue: 3 Pages: 4075-4086
Publisher: Baghdad University جامعة بغداد

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Abstract

This study included the convective air drying of a single sweet potato sample which is taken as an ellipsoid with (40mm) in the longitudinal direction and (20mm) in the thickness direction. Convective heat and mass transfer takes place between the sample surface and its drying environment; while, unsteady heat conduction and moisture diffusion take place within the drying body without phase change for liquid (evaporation occurs at the surface only). The numerical solution of the mass, energy conservation equations was used; by applying the finite difference technique after using the body fitted coordinate system with grid generation techniques. A set of empirical correlations have been employed to determine the product properties and the important affecting factors on the drying process were studied. The results showed that the product temperature is increased and its moisture content is decreased with time and the increase in air velocity caused an increase in the heat transfer coefficient and as a result moisture content will decrease and this accelerates the drying process. The numerical results were compared with experimental results and showed good agreement.

تضمنت هذه الدراسة استخدام الهواء كوسط تجفيف لعينة مفردة من البطاطا الحلوة ذات شكل بيضوي ذات (40) ملم طول و(20) ملم سمك. يحصل ا نتقال الحرارة بالحمل بين سطح العينة ومحيط تجفيفها بينما يحصل انتقال الحرارة بالتوصيل وانتقال الرطوبة بالانتشار داخل العينة بدون حدوث تغير بالطور للسائل الرطوبي (التبخر يحصل على السطح فقط). تم استخدام الحل العددي لمعادلات حفظ الطاقة والكتلة باستخدام طريقة الفروقات المحددة بعد استخدام نظام مطابقة احداثيات الجسم مع تقنيات التوليد الشبكي. الحسابات العملية استخدمت في هذا البحث مجموعة من المعادلات التجربية لحساب خواص المنتج مع دراسة اهم العوامل المؤثرة على عملية التجفيف بينت النتائج زيادة درجة حرارة المنتج ونقصان محتواه الرطوبي مع الزمن وان زيادة سرعة هواء التجفيف تسبب زيادة معامل انتقال الحرارة بالحمل وكنتيجة لذلك يتناقص المحتوى الرطوبي وهذا يعجل من عملية التجفيف.قورنت النتلئج العددية مع النتائج العملية وبينت توافق جيد.


Article
Preparation and Formation of Zeolite 5A from Local Kaolin Clay for Drying and Desuphurization of Liquefied Petroleum Gas

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This work deals with preparation of zeolite 5A from Dewekhala kaolin clay in Al-Anbar region for drying and desulphurization of liquefied petroleum gas. The preparation of zeolite 5A includes treating kaolin clay with dilute hydrochloric acid 1N, treating metakaolin with NaOH solution to prepare 4A zeolite, ion exchange, and formation. For preparation of zeolite 4A, metakaolin treated at different temperatures (40, 60, 80, 90, and 100 °C) with different concentrations of sodium hydroxide solution (1, 2, 3, and 4 N) for 2 hours. The zeolite samples give the best relative crystallinity of zeolite prepared at 80 °C with NaOH concentration 3N (199%), and at 90 and 100°C with NaOH concentration solution 2N (184% and 189%, respectively). Zeolite 5A was prepared by ion exchange of zeolite 4A prepared at 90°C and 2N NaOH concentration with 1.5 N calcium chloride solution at 90 °C and 5 hours, the ion exchange percentage was 66.6%. The formation experiments included mixing the prepared powder of 5A zeolite with different percentages of kaolin clay, citric acid and tartaric acid to form an irregular shape of zeolite granules. Tartaric acid binder gives higher bulk crushing strength than that obtained by using citric acid binder with no significant difference in the surface area. 7.5 weight% tartaric acid binder has the higher bulk crushing strength 206 newton with surface area 267.4 m2/g. Kaolin clay binder with 15 weight% gives the highest surface area 356 m2/g with bulk crushing strength 123 newton, it was chose as the best binder for zeolite 5A. The prepared granules of 5A zeolite were used for the adsorption experiments of H2O, and H2S contaminants from LPG. Different flow rates of LPG (3, 4, and 5 liter/minute) were studied. It was found that H2O is the strongly adsorbed component and H2S is the weakly adsorbed component. The best flow rate in this work for H2O, and H2S adsorption is 5 liter/minute of LPG. The adsorption capacity for H2O was 7.547 g/g and for H2S was 1.734 g/g.


Article
Effect of Transverse Base Restraint on the Cracking Behavior of Massive Concrete

Authors: Ala’a H. A. Al-Zuhairi --- Omar Al-Farouq Al-Damluji --- Adnan F. Ali
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2007 Volume: 13 Issue: 3 Pages: 1701-1719
Publisher: Baghdad University جامعة بغداد

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Abstract

The effect of considering the third dimension in mass concrete members on its cracking behavior is investigated in this study. The investigation includes thermal and structural analyses of mass concrete structures. From thermal analysis, the actual temperature distribution throughout the mass concrete body was obtained due to the generation of heat as a result of cement hydration in addition to the ambient circumstances. This was performed via solving the differential equations of heat conduction and convection using the finite element method.The finite element method was also implemented in the structural analysis adopting the concept of initial strain problem. Drying shrinkage volume changes were calculated using the procedure suggested by ACI Committee 209 and inverted to equivalent temperature differences to be added algebraically to the temperature differences obtained from thermal analysis.Willam-Warnke model with five strength parameters is used in modeling of concrete material in which cracking and crushing behavior of concrete can be included. The ANSYS program was employed in a modified manner to perform the above analyses. A thick concrete slab of 1.5m in thickness and 10m in length was analyzed for different widths 2, 4, 8, and 10m to produce different aspect ratios (B/L) of 0.2, 0.4, 0.8, and 1.0 respectively. The results of the analyses show an increase in cracking tendency of mass concrete member as the aspect ratio of the same member is increased due to the effect of transverse base restraint. Accordingly, such effect cannot be ignored in the analysis of base restrained mass concrete structures subjected to temperature and drying shrinkage volume changes.

في هذا البحث، تم إجراء تحري عن تأثير أخذ البعد الثالث في أعضاء الخرسانة الكتلية بنظر الاعتبار على تشققها. وتتضمن الدراسة إجراء التحليل الحراري والإنشائي لمنشآت الخرسانة الكتلية. ويتم الحصول على التوزيع الحقيقي لدرجات الحرارة خلال جسم الخرسانة الكتلية من خلال التحليل الحراري للمسألة نتيجة للحرارة المتولدة جراء إماهة السمنت بالإضافة إلى الظروف الجوية المحيطة. وهذا يجرى من خلال حل المعادلتين التفاضليتين للتوصيل والحمل الحراري باستخدام طريقة العناصر المحددة.كما إن طريقة العناصر المحددة أستخدمت أيضا في التحليل الأنشائي وذلك بتبني فكرة مسألة الأنفعال الابتدائي. كذلك يتم احتساب التقلصات الحجمية المرافقة لجفاف الخرسانة بالاعتماد على الطريقة المقترحة من قبل معهد الخرسانة الأمريكي لجنة 209 والتي يتم تحويلها إلى ما يكافئها من تغير في درجات الحرارة لتضاف جبريا إلى التغيرات بدرجات الحرارة التي تم الحصول عليها من التحليل الحراري.لقد تم تبني نموذج ويلام-ورانك ذات خمسة معاملات مقاومة لتمثيل مادة الخرسانة إذ يتضمن هذا النموذج تصرف الخرسانة في حالتي التشقق والتهشم. هذا وتم استخدام برنامج ANSYS وبطريقة معدلة لإنجاز التحليلين المشار أليهما أعلاه. تم تحليل بلاطة خرسانية بسمك 1.5م وطول 10م وبأعراض مختلفة 2، 4، 8 و10م لتحقيق نسب جانبية عرض/طول مختلفة 0,2، 0,4، 0,8و 1,0 على الترتيب. أظهرت نتائج التحليل زيادة في قابلية تشقق أعضاء الخرسانة الكتلية بزيادة النسب الجانبية بسبب تأثير تقييد القاعدة العرضي. وعليه، فأن مثل هذا التأثير لا يمكن إهماله في منشآت الخرسانة الكتلية التي تتعرض لتغيرات في درجات الحرارة و تقلص الجفاف.

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