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Article
CAUSES AND TREATMENT OF DYSTOCIA IN IRAQI AWASSI EWES
مسبباث وعلاج حالاث عسر الولادة في النعاج العواسية العراقية

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Abstract

A one hundred thirty two Awassi ewes aged between 1.5-4 years old suffering from dystocia, were brought by farmer to Veterinary Teaching Hospital related to College of Veterinary Medicine- University of Mosul-Mosul governorate- Iraq, treated during the lambing seasons for three years started from November 2010 to end of December 2012. Results of this study were recorded ring womb as main causes of dystocia, the maximum percentage was 81.8 %( 108,132). The other causes of dystocia were fetal mal-position 8.3% (11,132), narrow pelvic 5.3 %( 7,132), monster fetus %3.0(132,4), complicated cases (interfering more than one cause) 1.5%(2,132). although several methods of treatment have been tried, correction and manual treatment, hormonal treatment, cesarean section and fetotomy: Cesarean section had higher a positive response during treatment 61.2%, correction and manual traction recorded as second best treatment of dystocia 24.2%, hormonal treatment 12.8% and fetotomy 0.7%. It could be concluded that ringworm (maternal origin) was the major causes of dystocia in Iraqi Awassi ewes; cesarean section appears to be a safe and successful procedures for management of dystocia if performed as early as possible.

Keywords

Dystocia --- Awassi --- treatment


Article
Negative Effect of Laser Treatment with Nd:YAG on the Corrosion of Amalgam in Artificial Saliva
التأثير السلبي للمعاملة الليزرية بليزر Nd:YAG على تأكل الحشوة الزئبقية في اللعاب الاصطناعي

Author: Lec. Fatima I.Sultan
Journal: journal of the college of basic education مجلة كلية التربية الاساسية ISSN: 18157467(print) 27068536(online) Year: 2013 Volume: 19 Issue: 79 / علمي Pages: 863-873
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

This work involves study the corrosion behavior of amalgam in artificial saliva at pH=6 and 37oC after using Nd: YAG, where this laser used for healing the cancer. This study indicates that laser surface treatment affecting corrosion resistance of amalgam, and the results indicate that the laser treatment don`t give the desired purpose because the nature of amalgam and the presence of mercury in this alloy which may be evaporate and it give toxicity for human and the energy of treatment must be low to avoid evaporation. In this work, laser treatment with two pulses under experimental conditions gave little improvement in corrosion resistance of amalgam compared with one and three pulses through the corrosion parameters of polarization behavior.

يهدف هذا البحث الى دراسة سلوك التأكل للحشوة الزئبقية بعد المعاملة الليزرية بليزر Nd:YAG في اللعاب الصناعي عند اس هيدروجيني 6 ودرجة حرارة 37 درجة مئوية حيث يستخدم هذا الليزر لمعالجة الاورام في اللثة. ان الدراسة الحالية اثبتت بان المعاملة الليزرية تؤثر على مقاومة التأكل بسبب طبيعة الحشوة الزئبقية الحاوية على الزئبق والذي قد يتبخر معطياً تأثيراً سمي وان الطاقة الليزرية يجب ان تكون اقل ما يمكن. ان المعاملة الليزرية في هذا البحث بضربتين ليزريتين اعطت تحسناً قليلاً في مقاومة التأكل مقارنة مع المعاملة الليزرية نبضة واحدة وثلاث نبضات كما تبينه متغيرات التأكل المقاسة من سلوك الاستقطاب.

Keywords

Amalgam --- Laser treatment --- Corrosion


Article
Biotreatment of Al-Yarmook Hospital Wastewater Using Packed Bed Bioreactor
المعالجة الحيوية لمياه صرف مستشفى اليرموك باستخدام مفاعل حيوي نوع العمود المحشو

Author: Mohammed B. Abdul Kareem
Journal: Iraqi Journal of Biotechnology المجلة العراقية للتقانات الحياتية ISSN: 18154794 Year: 2013 Volume: 12 Issue: 1 Pages: 91-100
Publisher: Baghdad University جامعة بغداد

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Abstract

Biotreatment systems of wastewater for hospitals are a challenge for environmental engineers. In this study, a pilot- scale system of aerobic fixed film packed bed was constructed for wastewater treatment of Al-Yarmok hospital which located in Baghdad. The aim of this study was to test the performance of fixed film packed-bed for elimination of the organic compounds from wastewater under aerobic condition. The parameters studied were: inoculums concentration, circulation rate, packing type and temperature. The results showed that the system efficiently removed about 85% of the chemical oxygen demand (COD) and 82% of Biological oxygen demand (BOD), while percent reduction in turbidity was about 93% and reduction in nitrate concentration was about 85%. It was found that temperature of 35oC and circulation rate of 16 L/min and inoculums concentration of 5% gave the best results for biotreatment of wastewater.

تعتبر عمليات معالجة مياه الصرف الخاصة بالمستشفيات من الامور المهمة بالنسبة لمهندسي البيئة. في هذا البحث تم نصب عمود محشو لغرض اجراء دراسة تجريبية لمعالجة مياه الصرف الخارجة من مستشفى اليرموك في بغداد وتحت ظروف هوائية. ان المتغيرات التي تمت دراستها تتضمن تركيز اللقاح ,معدل تدوير المياه الملوثة خلال العمود ,نوع الحشوة المستخدمة ودرجة الحرارة. بينت النتائج ان الجهاز يزيل تقريبا 85% من الاوكسجين المطلوب كيمياويا ((COD وكذلك 82% من الاوكسجين المطلوب حيويا (BOD). بينما كانت نسبة ازالة العكورة 93% ونسبة ازالة ايونات النتروجين بحدود 85%. اوضحت النتائج العملية ان درجة حرارة 35 مْ ومعدل تدوير 16 لتر / دقيقة وتركيز لقاح 5% تعطي افضل النتائج لمعالجة مياه الصرف. يمتاز العمود المحشو المستخدم بسهولة نصبه وصيانته فضلا عن انه ذو كفاءة عالية في عملية المعالجة.


Article
Outcome of 50 Iraqi Patientswith Acute Lymphoblastic Leukemia Treated by Modified German Multicenter Study Group (GMALL) Protocol

Author: Alaa Fadhil Alwan
Journal: Mustansiriya Medical Journal مجلة المستنصرية الطبية ISSN: 20701128 22274081 Year: 2013 Volume: 12 Issue: 2 Pages: 45-51
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Background and aim: Acute lymphoblastic leukemia (ALL) is a lymphoidmalignancy, which arises from bone marrow,appearing in marrow, blood circulation and otherorgans. Treatment outcome have significantly improved since the adaptation of intensification and risk adapted therapy-based on identified prognostic markers. Treatment programs in adult ALL have evolved from the successful strategies employed in pediatric ALL and incorporate multiple active agents into complex regimens. The goal of these doses intensive regimens is rapid cytoreduction with restoration of normal hematopoiesis, The aim of the study was to assess the efficacy of a modified German multicenter study group for Acute Lymphoblastic leukemia (GMALL) protocol in adult acute lymphoblastic leukemia (ALL( in respect to disease free survival (DFS) and overall survival(OS) and to determine the prognostic factors affecting this outcome. Patients and method: A prospective study conducted in the hematology unit in Baghdad Teaching Hospital on 50 patients with newly diagnosed (ALL) between January 2006 to January 2008.A written informed consent were obtained from all patients. All patients were undergone full clinical examination with full laboratory investigations. The diagnosis based on morphology and cytochemical stains (periodic acid-Schiff, Sudan Black) of bone marrow examination. In Modified GMALL, induction phase consist of 2 phases, phase 1 induction was given over 5 weeks with weekly vincristine (VCR), Doxorubicin(DOX), and continuous oral prednisolone(RDN), Phase II induction consisted of 3 doses of weekly cyclophosphamide(CYCLO) alternating with 3 doses of weekly cytosine arabinoside (ARA-C) combined with CNS directed therapy using intrathecal Methotrexate (MTX) with daily 6-mercaptopurine(6-MP) followed by cranial irradiation. Consolidation consisted of weekly VCR and two courses of 5 days Ara-C and Etoposide (ETOP) with dexamethasone (DEXA) over a period of 4 weeks and maintenance therapy of daily 6-MP tablets and weekly MTX tablets. Results: The study included 50 patients with median age of (28.5 years), ranged from 16-71 years. Thirty-one patients (62%) were males, while 19 patients (38%) were females. All patients received modified GMALL protocol; forty-two patients (84%) achieved complete remission (CR). The DFS and median OS were 8.5 months, 10 months respectively. The median OS at 1 year was 54%. Deaths occurred in 19 patients (38%). Infection was the main cause of death.In univariate study analysis, age less than 30 years, absence of hepatomegaly and lymphadenopathy, and peripheral blast percent less than 50% were associated with better OS while presence of lymphadenopathy was considered poor prognostic factors and associated with low CR rate, short DFS, and OS. Conclusion: The modified GMALL protocol produced good induction remission rate but with lower survival rate in comparison to other intensive adult protocols. This study also showed that there are certain bad prognostic factors such as age more than 30 years, hepatomegaly and lymphadenopathy which adversely affect the outcome


Article
Gender differences, facial profile and treatment need of malocclusion for a sample of Al-Muthanna governorate students aged 15 years

Author: Hayder S. Al-Atabi
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2013 Volume: 25 Issue: 3 Pages: 142-148
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Survey of the occlusion in population groups usually include in their objections the academicassessment of occlusal feature, the planning resources for public health treatment programmers, the comparison ofdifferent population and the screening of groups for orthodontic treatment. Likewise a thorough investigation of theoccurrence of malocclusions among school–students would be of major importance in the planning of orthodontictreatment in the public dental health services. For this purpose it is necessary to have detailed information on theprevalence of individual malocclusion among boys and girls at different ages distributed regionally, and moreover,an analysis of the need for orthodontic treatment in the different school classes.Materials and methods: This study was conducted from 20th October 2011 to 9th May 2013 on (3424 ) students (1712males and 1712 females); from which 62 students (1.8%) were excluded because of incomplete information (nomolar relation can be attended) giving a valid sample of 3362 (1681 males and 1681 females) aged (15) years oldwere studied with respect to facial profile ,sagittal occlusion according to Angle's classification, overjet, overbite,anterior crossbite , posterior crossbite, scissorsbite, rotation and displacement spacing and crowding.Results: The normal profile were presented in (73.76%) students (74%) males and (73.53%) females. Convex profileswere presented (20.34%) students (20.46%) males and (20.23%) females. A concave profile were presented in (5.9%)students (5.54%) males and (6.24%) females), The malocclusion were presented (73.05%) students (73.46%) malesand (72.64%) females, According to the Dental health component of index of the orthodontic treatment subjectswith no need for treatment were about 44.11% , the subjects who need little treatment were about 26.82%, 13.06% ofthe subjects who need moderate treatment, 10.03% great treatment need and about 5.98% very greatly treatmentneed.Conclusions: Orthodontic treatment need according to IOTN shows that there was no significant difference betweenmales and females in the malocclusion, Facial profile and treatment need


Article
Wear Performance of a Laser Surface Hardened ASTM 4118 Steel
سلوك البلیان للفولاذ 4118 ASTM المصلد سطحیا باللیزر

Author: Assifa M. Mohamad
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2013 Volume: 31 Issue: 17 Part (A) Engineering Pages: 3235-3244
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this investigation ASTM 4118 steel was treated by using pulse Nd: YAGlaser with wave length 1064nm and pulse duration 100ns. In order to assess thenew tribological properties of laser surface hardened ASTM 4118 steel, the wearresistance between specimens treated with laser and those of conventionallyhardened under dry sliding conditions was compared. The change of wearmechanisms in laser hardened 4118 steel resulted in distinct difference in wearrates.The results showed that quenched zones not only had sufficient depth ofhardening and higher hardness, but had more retained austenite and finer carbidesbecause of a higher degree of carbide dissolution. Laser surface hardened ASTM4118 steel specimens exhibited superior wear resistance to their conventionallyhardened specimens due to the change in the microstructure hardening, highhardness. The wear mechanism for both the laser quenched layer andconventionally hardened layer was highly similar, generally involving adhesivewear mechanism , material transfer, wear induced oxidation and plowing. Also theresults of hardness show that increases with increasing of laser energy by 70%.


Article
EEFECT of ROW SPACE and PRE-HARVEST TECHNIQUE TREATMENTS on QUALITATIVE CHARACTERS of WHITE MUSTARD (Sinapis alba L.)
تأثير مسافات الز ا رعة بين الخطوط ومعاملات ما قبل الحصاد في الصفات النوعية لمخردل الأبيض (Sinapis alba L)

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To study the effect of row space and pre-harvest technique treatments on qualitative characters of white mustard, Sinapis alba L, Experiment was conducted in the field of experiments at the College of Agriculture , University of Baghdad /Abu - Graib during 2003 - 2004, using split plots design with three replications arranged in RCBD , the main treatments included three row space 20 , 40 and 60 cm. while the sub – plot treatments included pre-harvest treatment of plants which included plants harvested at physiological maturity stage, harvest of plants at full maturity stage , harvest of plants at full maturity stage after GA3 application, and harvest of plants at full maturity after Auxin application. The results obtained showed: Row space of 20 cm lead to significant increase in oil percentage of seeds , oil yield and volatile oil yield which were 39.02% , 879.7 kg / ha , and 1.67 L / ha respectively as compare with row space of 60cm which gave 36.34 %, 518.23 kg/ha, and 1.16 L/ha respectively. Row space of 60 cm lead to significant increase in percentage of seeds field germination 84.17% followed by row space of 40 cm while row space of 20 cm gave least percentage to this character 76.58%. Treatment of plant harvested at full maturity stage after Auxin application affected significantly percentage of oil in seed ,oil yield and volatile oil yield which were 38.83%, 773.86 kg/ha and 1.46 L/ha respectively comparative with treatment of plants harvest at physilogical maturity stage which gave least percentage of oil in seed, oil yield and volatile oil yield which were 35.63%, 642.7 kg/ha and 1.30 L/ha, respectively. However treatment of plants harvested at philological maturity stage affected significantly in increase the percentage of protein which gave %19.45 as compare to treatment of plants harvested at full maturity after Auxin application which gave 15.76% . Also the same treatment lead to significant increase in percentage of unsaturated fatty acid Eicosenoic acid, seeds laboratory and field germination which were %15.47, 93.22% and 83.89%, respectively. while treatment of plants harvested at full maturity gave 14.22 %, 91.00% and 75.67%, respectively.


Article
Delayed Management in Acute Abdomen: causes and consequences
إرجاء التدابير العلاجية في حالات البطن الحادة: الاسباب والنتائج

Authors: Haqqi I. Razzouki حقي اسماعيل رزوقي --- Amer H. Salman عامر حسن سلمان
Journal: IRAQI JOURNALOF COMMUNITY MEDICINE المجلة العراقية لطب المجتمع ISSN: 16845382 Year: 2013 Volume: 26 Issue: 1 Pages: 78-84
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

ABSTRACT:Background: Acute abdomen is a serious life-threatening condition which needs prompt diagnosis and management. However, in many situations, there is a delay in management which may affect the clinical outcome and worsen the prognosis.Objectives: To determine the causes of delay in diagnosis and treatment in acute abdomen and to study the effects on prognosis.Patients and Methods: A prospective case-series study done in Al-Yarmouk teaching hospital, surgical department over a six months period from 1st of April 2011 to the 1st of October 2011.Ninety five Patients presented with acute abdomen were divided into two groups according to the duration of their symptoms. Thirty five patients who presented after 24 hours were considered delayed and 60 patients who presented before 24 hours were considered as controlled group. Both groups were followed closely and the operative findings, Post-operative complications and the final clinical outcome were documented.Results: There were 35 patients with delayed acute abdomen. The delay was due to the patient or his family in 19 (54.2%) cases and due to medical factors in 11(31.4%) patients. The most common operative finding was perforated duodenal ulcer 5 (14.2%) patients and perforated appendix 5 (14.2%) patients. Thirty (85.7%) patients developed post-operative complications mainly prolonged paralytic ileus, peritonitis and early surgical site infection. The total post operative complications were 25 (71.4%) patients and full recovery was 5 (14.3%).There were 5(14.3%) deaths due to septic shock or cardiovascular complications. Sixty patients presented within 24 hours and considered as controlled group, The most common operative finding was perforated duodenal ulcer 30 (50%) patients, and obstructed or strangulated hernia was 15 (25%) patients, the total post operative complications in this group was (25%) P-value 0.006 (significant), full recovery was found in 42 (66.6%) patients P-value 0.0007(significant), there was no deathConclusions: Although many factors causing delay management in cases of acute abdomen are mainly related to the patient, there were a significant number of cases in which the attending doctor was responsible for the delay. There was a definite relationship between the delay in diagnosis and management and the incidence of complications and Death. Keywords: Acute Abdomen; Delayed treatment; causes, consequences

خلفية البحث: ان حالات البطن الحاد تكون في اغلب الاحيان شديدة مع خطر الموت و تحتاج الى تشخيص سريع و تداخل عاجل . هناك في حالات عديدة تاءخير في المعالجة مما يؤثر على النتائج السريرية و يؤدي الى تدهور في التكهناهداف البحث: لتحديد اسباب التاخير في التشخيص و المعالجة لحالات البطن الحاد و لدراسة المضاعفات المترتبة على هذا التأخير ومدى تأثيرها على التكهنات.المرضى و طرق البحث: دراسة مستقبلية شملت المرضى المصابين بالبطن الحاد الداخلين الى قسم الجراحة في مستشفى اليرموك التعليمي لمدة ستة اشهر. تم تقسيم المرضى الى مجموعتين حسب الفترة ما بين ظهور الاعراض و وصولهم المستشفى واعتبرت الحالات الواصلة بعد 24 ساعة متأخرة0 لاغراض البحث تم متابعة المجموعتين تفصيليا وتوثيق مشاهدات العمليات الجراحية والمضاعفات بعد العمليات و النتائج السريرية.النتائـــــــــج: كانت هناك 35 حالة بطن حاد متأخرة .كانت العوامل المتعلقة بالمريض او عائلته هي سبب التأخير في 19 مريضا و العوامل المتعلقة بالكادر الطبي هي السبب في 11 مريضا.الحالات الاكثر حدوثا هي انثقاب قرحة الاثني عشري و انثقاب الزائدة الدودية.حدثت مضاعفا ت بعد العملية في 30 مريضا اكثرها شيوعا شلل الامعاء المطول و التهاب غشاء البريتون و التهاب جرح العملية. وحدوث خمس وفيات بسبب الصدمة الجرثومية او اختلاطات متعلقة بالقلب و جهاز الدوران .الاستنتاجات: ان العوامل المتعلقة بمعالجة حالات البطن الحادة المتأخره تعود اساسا الى المريض و عائلته الا ان هناك حالات كثيرة يعود السبب للكادر الطبي و لاسباب متعددة. هناك علاقة مؤكدة بين التدابير العلاجية في حالات البطن الحاد المتأخرة و بين زيادة الاختلاطات بعد العملية و كذلك زيادة وقوع الوفيات مقارنة بالحالات التي تم علاجها مبكرا.


Article
Effect of Laser Surface Treatment on Physical Properties of Composite Material (Al-B4C)
تأثير المعاملة الحرارية السطحية بالليزر على الخواص الفيزياوية لمادة متراكبة (Al-B4C)

Authors: Khansaa D. Selman خنساء داود سلمان --- Sabah N. Mahmood صباح نوري محمودد --- Qamar Q. Mohameed قمر قاسم محم
Journal: Iraqi Journal of Science المجلة العراقية للعلوم ISSN: 00672904/23121637 Year: 2013 Volume: 54 Issue: 4 Pages: 882-887
Publisher: Baghdad University جامعة بغداد

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Abstract

This work study the effect of laser surface heat treatment on physical properties (green density, density after sintering, theoretical density and porosity)of a composite material of an Al powder as a matrix with different percentage of B4C powder as additive material. This work was done by two stages: First stage: Production the maincomposite material which is contain Al powder with grain size 24μm as a matrix and B4C powder with grain size 50μm as additive with different weight percentage (5%,10%,15%,20%,25%,30%), and the powders Maxined for suitable time 15min, after that the mixture compacted with 2ton and sintered at 550C0. Second stage: Laser surface treatment was done for the productive composite material after sintering by using pulse Nd: YAG laser with 1J energy, wave length 1064nm and pulse duration 100ns.Laser surface heat treatment was carried out with one pulse and two pulses respectively. Macrohardness of the composite material was measured after the sintering process and after the laser surface heat treatment with one pulse and two pulses, also photo-micrographies were taken for the specimens by using ordinary microscopic after each of sintering process and laser surface heat treatment. The results show that improvement of physical properties mentioned above and macrohardness after laser surface treatment with two pulses more than one pulse.

في هذا البحث تمت دراسة تاثير المعاملة الحرارية السطحية بالليزرعلى الخواص الفيزياوية (الكثافة الخضراء ,الكثافة بعد التلبيد, الكثافة النظرية والمسامية) لمادة متراكبة من مسحوق الالمنيوم كمادة اساس مع نسب مختلفة من مسحوق رابع كاربيد البورون (C4B) كمادة مضافة. تم اجراء البحث على مرحلتين: المرحلة الاولى: انتاج المادة المتراكبة المتكونة من مسحوق الالمنيوم بحجم حبيبي كمادة اساس مع مسحوق (C4B) بحجم حبيبي كمادة مضافة وبنسب وزنية (%5,% 10,%15,%20,%25,%30), ومن ثم تمت عملية خلط المساحيق لمدة min15 ,بعد ذلك اجريت عملية التدميج بكبس الخليط بضغط والتلبيد عند درجة حرارية . المرحلة الثانية: اجريت المعاملة الحرارية السطحية بالليزر للمادة المتراكبة المنتجة بعد عملية التلبيد باستخدام ليزر نيديوم – ياك النبضي بطاقة مقدارها , بطول موجة nm1064 وزمن نبضة ns100. وقد اجريت المعاملة السطحية بالليزر بنبضة واحدة وبنبضتين على التوالي. تم حساب الصلادة الماكروية للمادة المتراكبة بعد التلبيد وكذلك بعد المعاملة السطحية بالليزر لنبضة واحدة ونبضتين, كذلك تم تصوير العينات باستخدام المجهر الضوئي الاعتيادي للعينات بعد كل من عملية التلبيد والمعاملة السطحية بالليزر.اظهرت النتائج تحسن في الخواص الفيزياوية المذكورة في اعلاه وكذلك الصلادة الماكروية بعد المعاملة السطحية بالليزر بنبضتين اكثر مما هو عليه للنبضة الواحدة.


Article
EVALUATION OF TELLOL AL-KIEND CLAY IN MOSUL CITY FOR THE PRODUCTION OF LIGHT WEIGHT AGGREGATES

Authors: Doaa M. Hammed --- Mayada S. Joodi --- Abdul Wahab AR. Al-Ajeel
Journal: Iraqi Bulletin of Geology and Mining مجلة الجيولوجيا والتعدين العراقية ISSN: 18114539 Year: 2013 Volume: 9 Issue: 2 Pages: 151-160
Publisher: Ministry of Industry and Minerals وزارة الصناعة والمعادن

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Abstract

In this research a representative sample from Tellol Al-Kiend clay deposit (Injana Formation), Naenava Governorate, Iraq, was evaluated for lightweight aggregates preparation. Two methods of heat treatment were carried out. Iso-thermal treatment conducted at (1180 – 1200) °C range, for aggregates made from clay only, using different socking time. Whiles, rapid (or flush) firing, were carried out at 1200 °C, for aggregates made from clay with different types and amounts of additives (dolomite, waste engine oil, and straw). The iso-thermal tests reveal that bloating can occurs at 1180 °C only for 45 minutes holding time. The aggregates obtained, have a specific gravity of about 1.38 and 0.8% water absorption. In rapid firing, it was found that, the bloating of the clay can be significantly improved by the addition of dolomite. The results obtained indicated that aggregates having 1.35 specific gravity with about 1% water absorption value could be produced from aggregates made of clay and 5 wt.% dolomite. The firing time has been about 5 minutes. Thereupon, it can be suggested that, Tellol Al-Kiend clay can be used for the production of lightweight aggregates by rapid firing. Concrete made from these lightweight aggregates shows a compressive strength (28 days) of about 173 kg/cm2, which can be designated as structural and insulating concrete.

جرى في هذا البحث تقييم نموذج ممثل لترسبات أطيان تلول الكند (تكوين إنجانة) في محافظة نينوى لإنتاج الركام الخفيف، وجربت طريقتان للمعالجة الحرارية. جرى في الطريقة ألأولى معالجة الركام المحضر من الطين فقط في درجات حرارة تتراوح مابين (1180 ـ 1200) °م وزمن استبقاء مختلف. أما الركام المحضر من الطين مع كميات وأنواع مختلفة من المواد المضافة (دولومايت، مخلفات زيت المحركات والقش) فقد تم معالجتها بالحرق السريع (أو المفاجئ) عند درجة حرارة 1200 °م مع زمن استبقاء 2 أو 3 دقائق. بينت نتائج حرق الركام المحضر من الأطيان فقط بأن الانتفاخ يمكن أن يحصل فقط عند حرارة 1180 °م وبزمن استبقاء 45 دقيقة، وإن الركام الناتج من هذه العملية أعطى كثافة نوعية بحدود 1.38 ونسبة امتصاص للماء 0.8%. ولكن وجد أنه باستخدام الحرق المفاجئ فإن انتفاخ ركام الطين يتحسن بشكل ملحوظ عند إضافة الدولومايت وبينت النتائج المستحصلة من هذه العملية إمكانية إنتاج ركام يمتلك كثافة نوعية بحدود 1.35 ونسبة امتصاص للماء 1% عند إضافة 5% وزناً من الدولومايت للطين وإن الزمن اللازم للحرق هو بحدود 5 دقائق. وعليه يمكن استخدام أطيان تلول الكند في إنتاج الركام الخفيف بإتباع الحرق السريع. كما بينت نتائج فحص الكونكريت المحضر من الركام الخفيف بأن مقاومة الانضغاط بعد 28 يوم بحدود 173 كغم/ سم2 والذي يمكن أن يستخدم في تحضير الخرسانة الإنشائية العازلة.

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