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معالجة المياه الصناعية من المعادن السامة باستعمال مادة امتزاز محلية جديدة == A new Local Adsorbent for The Treatment of an Industrial Wastewater from Toxic Metals

اسم المؤلف: سحر فاضل عبد الرزاق الجمعة
اسم المشرف: الهام هاشم شمخي | مصطفى محمد رضا الفائز
الموضوع العام: الهندسة الكيمياوية
السنة: 2011
الموضوع الدقيق: الهندسة الكيمياوية
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

تقييم استعمالات الارض الحضرية في مدينة البصرة باستخدام نظم المعلومات الجغرافية وتقنيات الذكاء الاصطناعي == Evaluation of Urban Land Use in Basra City Using Geographical Information Systems and Artificial Intelligence Techniques

اسم المؤلف: لمياء صباح شهاب
اسم المشرف: كريم راضي حسين | خديجة عبد الزهرة حسين
الموضوع العام: علوم الحاسبات
السنة: 2018
الموضوع الدقيق: علوم الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

الصفات المظهرية والتشريحية والكيميائية والوراثية لثلاث اصناف متباينة النضج من نخيل التمر Phoenix dactylifera L == Morphological, anatomical, chemical, and genetic characteristics of Three cultivars varying in maturity stage of Date Palm(Phoenix dactylifera L

اسم المؤلف: يحيى نوري خلف
اسم المشرف: كاظم جاسم حمادي | عبد الكريم محمد عبد
الموضوع العام: علوم الحياة
السنة: 2017
الموضوع الدقيق: النبات - التشريح
الدرجة: دكتوراه
الجامعة: جامعة البصرة
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

دراسة تصنيفية وبيئية للنباتات المتطفلة في العراق == Taxonomical and Ecological Study of Parasitic Plants of Iraq

اسم المؤلف: وداد مزبان طاهر الاسدي
اسم المشرف: عبد الرضا اكبر علوان
الموضوع العام: علوم الحياة
السنة: 2017
الموضوع الدقيق: النبات - التصنيف
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

انتشار طفيلي الابواغ الخبيئة في بعض المجموعات المعرضة للاصابة في محافظة البصرة == Prevalence of Cryptosporidium in some risky groups at Basrah governorate

اسم المؤلف: هبة عبد الحسين كاظم
اسم المشرف: غازي يعقوب عزال الامارة | نائل حسين علي
الموضوع العام: الطب البيطري
السنة: 2015
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

دراسة مناعية - وبائية لداء المقوسات بين النساء المجهضات والقطط في محافظة البصرة == Immunological and Epidemiological Study of Toxoplasmosis Among Miscarriaged Women and Cats in Basrah Province

اسم المؤلف: منتهى عبد الحميد ناصر
اسم المشرف: غازي يعقوب عزال | ميسون شريف فليفل
الموضوع العام: الطب البيطري
السنة: 2015
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

تقيين السائل المنوي لذكور الماعز المحلي بالطريقة التقليدية وجهاز تحليل النطف بعد الحقن بمادة البروستوكلاندين اف 2 الفا == Evaluation of local Bucks semen by Traditional and Computerized Analyzer after injection of Prostaglandin F2 alpha

اسم المؤلف: زيد قتيبة معتوق
اسم المشرف: طاهر عبد المحسن فهد | عبد الباري عباس الفارس
الموضوع العام: الطب البيطري
السنة: 2015
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

ارتباط بعض اليلات الصنف الثاني HLA في الحساسيه للحم الاغنام والماعز في محافظة البصرة == Association of some of HLA class II alleles with allergy to lamb and goat meat in Basrah province

اسم المؤلف: رواء بناي زبيري
اسم المشرف: فوزية علي عبد الله | عدنان موسى الروضان
الموضوع العام: الطب البيطري
السنة: 2015
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

دراسة مظهريه - نسجيه وكيمونسجيه مقارنه بين الماشية و الجاموس المحلي في الغدد اللعابية الكبيرة == Comparative Histo - Morphological and Histochemical Study of the Major Salivary Glands Indigenous Cattle and Buffaloes

اسم المؤلف: رنا عماد المشهداني
اسم المشرف: عادل جبار حسين
الموضوع العام: الطب البيطري
السنة: 2016
الموضوع الدقيق: التشريح والانسجة والاجنة
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

دراسة تشخيصية تصنيفية لطفيليات القناة الهضمية في البط والوز في محافظة البصرة == DIAGNOSTIC AND TAXONOMICAL STUDY OF DIGESTIVE TRACT PARASITES IN DUCKS AND GEESE IN BASRAH GOVERNORATE

اسم المؤلف: اسراء فائق جعـفر
اسم المشرف: سـوزان عبد الجبار عبد العزيز
الموضوع العام: الطب البيطري
السنة: 2015
الدرجة: ماجستير
الجامعة: جامعة البصرة
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:

دراسة جيولوجية لتلي حرير، جنوب العراق == Geological study of Hareer's Tells, Southern Iraq

اسم المؤلف: خليل جبار موله السوداني
اسم المشرف: بدر نعمة عكاش البدران | جينفر رينيه بورونيل
الموضوع العام: علم الارض
السنة: 2015
الموضوع الدقيق: علم الارض
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: edimentology and dating studies were carried out for four archaeological sites, located in Hareer area. These sites are located in the southern part of Mesopotamian plain, north Basrah Governorate between two streams : Al - Mashab and Al - Sallal. The sites were visited four times in between 2013 and 2014. During three visits, 80 samples were collected, 20 Samples from each sample point were selected, individual site. At any sample point, specimens were taken at 0.25 m depth interval up to 5 m total depth. These samples were analyzed to determine grain size, fossils and their environments, sediments ages, minerals contents, carbonate content and organic material percentage. The last site visit was dedicated to a geophysical survey. Ground Penetrating Radar data of 783 m of total length was performed to prove archaeological structure existence.Grain size analysis showed three types of sediments : silt, mud, and sandy silt. These sediments were deposited by low - energy conditions. They can be classified as poorly sorted, platy kurtic and very platy kurtic to meso kurtic and course skewed to symmetrical skewed. Fossils assemblages suggest three biofacies : first B1, a marsh to fluvial environment was found in sites 1, 2, 3 and 4 at depth; from surface to about 1 - 1.5m. Second B2, a shallow/ upper estuarine, brackish marsh environment, was found in sites 1, 2, 3 and 4 at depth; 1.5m to about 3 - 3.5m. Third B3, a lower estuarine to marine environment was found in sites 1, 2, 3 and 4 at depth 3.5 - 5m. The existence of Elphidum excavatum, Ammonia beccarii, and Cyprideis torosa, could indicate that the environment was estuarine influenced by marine water. Out of 80 samples, only eight specimens were analyzed by C14 method to delineate the sediments ages. These ages were - 6638 to - 6456 cal CE in depth 4.8m; - 4717 to - 4546 cal CE in depth 4.25m; 1385 to - 1146 cal CE in depth 1.25m; - 385 to - 196 cal CE in depth 0.6m and 69 - 245 cal CE in depth 1m; 568 - 665 cal CE in depth 1,1m; 1167 - 1276cal CE in depth 0.25m; 1296 - 1415 cal CE in depth 0.5m which fall in Ubaid 0 - Neolithic; Ubaid 2; Kassite; Parthian - Sassanian; Sassanian; Seljuk - Abbasid - Mamluk/Mongol; Abbasid respectively.Mineral content analysis showed that calcite, quartz, dolomite and feldspar are the dominant bulk minerals. Their percentages graded from high to low. Calcite was the highest percentage (48%) and Feldspar was the lowest percentage (5%). Clay minerals assemblages analysis indicate that Kaolinite, illite, chlorite, montmorillionite, palygorskite, and mixed - layer of montmorillionite - chlorite, palygorskite - illite are presented in the four sites. The percentages of carbonate content in the sediments of sites 1,2,3, and 4 were 10.31% - 24.04% , 8.61% - 22.32% , 10.31% - 29.11% , and 8.58% - 25.56%, respectively; while the percentage of total organic carbon in the sites were 1.27% - 8.33% , 1.48% - 7.89% , 4.53% - 7% , and 1.86% - 5.70%.The GPR data at Tell 1 showed good evidences for archaeological features, that may represent buried archaeological walls of about 60 cm width. However, no archeological remains showed evidence at tell 2 that may be due to incorrect profile setting or bad layer dielectric contrasts. In both tells, scattered hyperbolas features were

قياس تراكيز الرادون للمستشفيات ,المراكز الصحية والمنازل وقياس البورون في مياه محافظة ذي قار - العراق == Measurements of Radon in Hospitals, Health Centers and Dwelling as well as Boron Measurements in Water of Thiqar Governorate(Iraq)

اسم المؤلف: احمد عباس محمد
اسم المشرف: عيسى جاسم محمد الخليفة
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: دكتوراه
الجامعة: جامعة البصرة
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: العمل الحالي يتضمن ثلاث دراسات اجريت جميعها في محافظة ذي قار جنوب العراق, حيث استخدم 976 نموذج فيها.الدراسة الاولى استخدمت 625 نموذج من كاشف الاثر LR 115 Type II جمعت من 40 منزل في كل قضاء , حيث تم قياس مستويات الرادون وخطر الاصابة بسرطان الرئة من خلال الطريقة السلبية . النتائج اظهرة مستويات مرتفعه وخصوصا في المطبخ مقارنتا مع الاماكن الاخرى وذلك بسبب غاز الطبخ والمياه المستعملة. ان المعدل للجرعة المكافئة السنوية للمطبخ تتغير من 2.316±0.172 في الناصرية الى0.759±0.0348 في سوق الشيوخ .اما الدراسة الثانية فقد استخدمت 186 نموذج من كاشف الاثر LR 115 Type IIجمعت من 57 مستشفى ومركز صحي , حيث استعملت الطريقة اعلاه لقياس مستويات الرادون وخطر الاصابة بسرطان الرئة هناك.لقد اظهرت النتائج ان مستويات الرادون في المستشفيات اعلى من نظيرتها في المراكز الصحية. ان اعلى معدل للجرعة المكافئة السنوية للمراكز الصحية 2.504±0.114 mSv/y بينما للمستشفيات3.150±0.091 mSv/y. في كلى الدراستين اعلاه وجد ان اغلب الجرعات الاشعاعية , ليست اعلى من المعدل العالمي 2.4 mSv/y , ولذلك فانها لا تشكل خطرا جديا على المتواجدين.ان الدراسة الثالثة هدفها قياس تراكيز البورون في مياه محافظة ذي قار , حيث ان امدادات المياه تاتي من مصدرين رئيسين وهما نهري دجلة والفرات, حيث جمع 165 نموذج من 55 موقع لثلاثة انواع من المياه (مياه نهر, مياه اسالة , مياه شرب) واستخدمت الطريقة اللونية لقياس تركيز البورون في عينات الماء. ان اعلى التراكيز سجلت لمياه الانهر في قضاء الناصرية 1.729 mg/l , ولمياه الاسالة سجلت في قضاء الجبايش 0.3 mg/l , اما مياه الشرب فسجلت في قضاء الجبايش 0.286mg/l ,حيث النتائج اظهرت كذلك ان نهر الفرات اكثر تلوثا بعنصر البورون وذلك بسبب ان المناطق ذات الكثافة السكانية العالية ,المصانع والمنشات الكبيرة تقع على ضفافه , حيث ان معدل لتراكيز البورون لنهر دجلة 0.244 mg/l , بينما لنهر الفرات 0.794 mg/l . الدراسة الحالية اظهرت ان تراكيز البورون لنهر دجلة ليست اعلى من المعدل العالمي (اقل من 0.5 mg/l) . بشكل عام نتائج نهر الفرات اعلى من المعدل العالمي 0.5 mg/l , ولكنها تبقى ضمن المستويات المنخفضة لتراكيز البورون , حيث حدد الاتحاد الاوربي المستويات المقبولة ب 1.0 mg/L عام 1998 , اما نيوزيلندا فحددته ب 1.4 mg/L. | The present work included three studies carried out in Thiqar Governorate southern of Iraq, where 976 samples has been used .The first study used 625 samples of LR 115 Type II dosimeters where collected from 40 dwelling in each distract, Passive method is used to measure the radon indoor levels and lung cancer risk. The results show higher indoor radon levels and radon effective dose especially in kitchen as compared to other locations. High values of radon activity may be due to use of water and cooking gas in kitchen.The average annual effective dose for kitchen varying from 2.316±0.172 mSv/y recorded in Al Nasiriya district to 0.759±0.0348 mSv/y recorded in Suq AlShyouk district.The second study used 186 samples of LR 115 Type II dosimeters collected from 57 Hospitals and Health centers, also Passive method is used to measure the radon indoor levels and lung cancer risk. The results show that the calculated indoor radon levels and radon effective dose in Hospitals are higher than that in Health Centers.The maximum average annual effective dose in Health Centers is 2.504±0.114 mSv/y , while for Hospitals is 3.150±0.091 mSv/y.In the two studies most of the radiation dose are not higher than the world wide average back ground dose of 2.4 mSv/y and hence they does not pose any serious threat to the occupants.The third study aims is to measure the concentration of boron in waters of Thiqar Governorate (southern of Iraq), the water is supplied from two major sources (Tigris and Euphrates Rivers). 165 samples collected from 55 location for three types of water (rivers water, Tab water, drink water). Colorimetric curcumin method is used to measure the boron concentration in the water samples. The maximum Boron concentrations in Thiqar Governorate for River water (surface water) (1.729 mg/l) in Nasiriya district, Tab water(0.3 mg/l) in Chibiesh district and Drink water (0.286mg/l) in Chibiesh district. The results shown that Euphrates river is more polluted with boron element, because its pass in highly occupied region and meager factories ,facilities lay on it, where Tigris average value 0.244 mg/l,while Euphrates average value 0.794 mg/l.The present work shows most of the boron concentration in Tigris river aren't higher than the world wide back ground <0.5 mg/l. In general Euphrates river results are higher than the world wide back ground, but it's still in the low concentration levels for boron, where the European Union established a value of 1.0 mg/L for boron in 1998 for the quality of water intended for human consumption, also New Zealand has established a drinking water standard for boron of 1.4 mg/L

تحضير ودراسة الخواص البصرية والكهربائية للمتراكبات البوليورية النانوية المواصلة PANI - DBSA/ MWCNTs وتطبيقاتها في الخلايا الشمسية == Preparation and Study The Optical and Electrical Properties of Nanocomposite (PANI - DBSA / MWCNTs) and Application in Solar Cell

اسم المؤلف: هناء هاشم عناية
اسم المشرف: كريمة مجيد زيدان
الموضوع العام: علوم الفيزياء
السنة: 2017
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: The present thesis Conducts polymer (polyaniline) doped with Dodycyl Benzene Sulfonic Acid (DBSA) was prepared by chemical polymerization and with the help of ammonium persulphat (NH4)2S2O8 as oxidizing agent.Multi well carbon tubes MWNTs are ultrasonically treated with strong acide using a 3 : 1 mixture of concentrated H2SO4 and HNO3, producing carboxylic groups c - MWNTs .Nanocomposite conducting polymers PANIDBSA/ MWCNTs was prepared with adding different weight ratios (0%,1%,2%,3%,5%)(MWNCTs to PANI - DBSA). Accordingly, films of these nanocomposite polymer were prepared by spin coating technique .To study the optical properties, these films were deposited on glass, and on interdigitated finger electrode for the - electrical properties.The chemical structure of the prepared polymers PANI - DBSA, c - MWNCT and PANI - DBSA/MWCNTs are characterized by the FTIR spectra .The results indicated an appearance of functional group of doping with DBSA and MWNCTs changed to c - MWNCTs.The structure of preparation films are characterized by X - RAD diffraction .The results show crystalline peaks partial crystallinity of the PANI - DBSA/MWNCTs. The grain size of polymer was calculated by Scherrer relation.Morphologies and diameters of the nanocomposite were studied by Atom ic Force Microscope(AFM) and Scanning Electron Microscope (SEM). The average diameters of nanocomposite change between (81 - 118) nm and the roughness increased with increasing of MWNCTs in nanocomposite. Ology and the thickness were measured by Scanning Electron Microscope (SEM).The result shows the polymer covered MWNCT.The optical properties of preparation film were studied from absorbance spectra at wave - lengths of (300 - 1100 nm). The analyses of optical measurement shows direct transition with energy gap decreasing increases MWNCTs about(3.4 - 1.9) eV. The reflection spectrum is analysed to find same optical constant like extension coefficient and refraction coefficient.The electric conductivity was measured and it was found that the thin films correlate with the ohmic behaviour at voltage under 10V.The electricalconductivity increases as the ratios of MWNCTs increases in PANIDBSA/ MWNCTs nanocomposite from(6.17x10 - 3 S/cm ) at 0wt% to (1.12x10 - 1 ????/cm ) at 5wt% .The effect of temperature on the electric conductivity of all ratios of thenanocompositesare also studied. The resultindicated the activationenergy decrease as MWNCTs increase from 0.15 at (0wt %) to 0.05 at (5wt %).In electronic applications of nanocomposite conducting polymers solar cell,two kinds of solar cells (ITO/TiO2/PANI - DBSA/MWCNTs/C/ITO ) and (ITO/TiO2/PANI - DBSA/MWCNTs/dye/C/ITO) were fabricated. The currentvoltage characteristics are measured at light source 100mw/cm2.The solar cell parameter like open circuit voltage VOC ,short circuit current JSC, shunt resistance RSh, series resistance RS, full factor FF, and efficiency η, are calculated. The efficiency of solar cell at different ratios of MWNCTs in PANI - DBSA/MWNCT were calculated. The result indicated that the efficiency increased as MWNCTs increase. The efficiency of solar cells also increases with adding dye.

استخدام البكتريا المختزلة للنترات المعزولة من مياة انتاج حقول النفط في البصرة في السيطرة على الانتاج الحيوي لغاز كبريتيد الهيدروجين المنتج بفعل البكتريا المختزلة للكبريت == Using of Nitrate Reducing Bacteria Isolated From Produced Water of Oil Fields in Basra in Control of Biogenic Hydrogen Sulfide Produced by Sulfate Reducing Bacteria

اسم المؤلف: وجدان حسين عبد الصاحب التميمي
اسم المشرف: كوثر هواز مهدي
الموضوع العام: علوم الحياة
السنة: 2015
الموضوع الدقيق: الاحياء المجهرية
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: تضمنت الدراسة الحالية استخدام تقنية الاقصاء بالتنافس الحيوي للسيطرة على الانتاج الحيوي لغاز كبريتيد الهيدروجين H2S من قبل الجراثيم المختزلة للكبريت في مزارع الدفعة والمفاعل الحيوي, اذ ان اضافة النترات او النتريت يحفز نمو الجراثيم المختزلة للنترات التي تنافس الجراثيم المختزلة للكبريت على المصادر العضوية وتستقصيها. جمعت 40 عينة من مياه انتاج حقول نفط نهران عمر واللحيس في البصرة خلال 6 اشهر للفترة من اب 2013 الى كانون الثاني 2014, عزلت مزارع خليطه من الجراثيم المختزلة للكبريت والمختزلة للنترات من تلك العينات وحسبت اعداد الخلايا لكلا النوعين باستخدام طريقه العد الاكثر احتمالا وقد اظهرت النتائج ان اعداد الجراثيم كانت منخفضة اذ بلغت اعداد الجراثيم المختزلة للكبريت بين7 - 4 خلية/100مل في حين كانت اعداد الجراثيم المختزلة للنترات اقل من 4 - 2 خلية/ 100مل. كما تضمنت الدراسة الحالية ايضا تنقيه للجراثيم المختزلة للكبريت والمختزلة للنترات واجراء التشخيص الجيني بتقنيه التفاعل التسلسلي لانزيم البوليمريز PCR والذي من خلاله تم تضخيم الجين16S rRNA وحدد تتابعه للتشخيص الى مستوى السلالة وقد اظهرت تحاليل المجتمع الجرثومي ان عزلات الجراثيم المختزلة للنترات قد امتلكت تطابقا بنسبة 99% مع الانواع Pseudomonas stutzeri وP. putida وHerbaspirillum huttiense وBacillus licheniformis اما عزلات الجراثيم المختزلة للكبريت فقد اظهرت النتائج انها امتلكت تماثل 99% للانواعShewanella hafniensis وDesulfotomaculum acetooxidans وDesulfosporosinus orientis مع افتراض ان جميع العزلات هي سلالات جديدة عالميا. كما اظهرت نتائج المعاملة بالنترات او النتريت في مزارع الدفعة وجود تاثير مثبط قوي على الجراثيم المختزلة للكبريت اذ لم يزداد مستوى الكبريتيد في جميع التراكيز المستخدمة ( 200 و400 و600 و800 و1000) ملغم/لتر من النترات والنتريت فقد تراوح مستوى تركيز الكبريتيد بين 4.2 و21 ملغم/لتر عند المعاملة مع النترات و23 و5.2 ملغم/ لتر مع النتريت, وتطابقت هذه النتائج مع تركيز الخلايا في جميع القناني المعاملة, اذ تراوح بين 0.26 - 0.001 و0.003 - 0.17 مع النترات او النتريت على التوالي بينما كانت هناك زيادة معنوية في تركيز الكبريتيد الذي بلغ 121 ملغم/لتر وتركيز الخلايا بامتصاصية بلغت 0.84 في عينات السيطرة.كان للجراثيم المختزلة للنترات تاثير مثبط قوي على نمو الجراثيم المختزلة للكبريت وانتاج الكبريتيد عند اضافة المغذيات المشجعة لنموها بمختلف التراكيز, اذ ازدادت فعاليه الجراثيم المختزلة للنترات واستهلكت كل من النترات او النتريت المضاف خلال 3 - 2 يوم من الحضن وكان اعلى تاثير مثبط لانتاج غاز كبريتيد الهيدروجين عند التركيز 1000 ملغم/لتر من النترات اذ اظهرت النتائج وجود انخفاض معنوي في مستوى الكبريتيد الى34 ملغم/لتر في حين كانت اعداد البكتريا 34.8 خلية/مل بعد عشرة ايام من المعاملة. اظهرت نتائج معالجة الحموضة طويلة الامد باستخدام المفاعل الحيوي وجود انخفاض حاد في انتاج غاز كبريتيد الهيدروجين بنسبة 94% بعد اضافة النترات والنتريت خلال فترة 60 يوما من المعاملة ,الاضافة المستمرة للنترات والنتريت بحوالي ( 333ملغم/اليوم للنترات و133ملغم/اليوم للنتريت) ادت الى تثبيط الفعالية الحيوية للجراثيم المختزلة للكبريت وانتاج غاز كبريتيد الهيدروجين, اذ انخفض مستوى الكبريتيد من 155 الى 10 ملغم/لتر واعداد الخلايا اكبرمن 1100 الى 3.5 خلية/ مل بما يعادل 99.6% , بينما ازدادت فعالية واعداد الجراثيم المختزلة للنترات من 1100 الى اكبر من 1100 خلية/مل.اظهرت نتائج معدل تاكل عينات الحديد المطاوع في المفاعل الحيوي بعد 60 يوما ان اعلى معدل للتاكل كان 70.7 ملغم/ سم2/ سنه في المفاعل غير المعامل بالنترات والنتريت بينما انخفض معدل التاكل الى 15.8 ملغم/ سم2/ سنه بعد نفس الفترة من التعرض في المفاعل المعامل وبنسبة انخفاض بلغت 55% مقارنة مع المفاعل غير المعامل. | This study includes the used of Bio Competitive Exclusion technology (BCX) to control biogenic production of hydrogen sulfide (H2S) by Sulfate Reducing Bacteria (SRB) in batch cultures and bioreactors. The injection of nitrate (NO3) and nitrite (NO2) promotes the growth of nitrate reducing bacteria (NRB) which outcompete (SRB) on carbon sources. A total of 40 samples were collected from produced water of oil production facilities in Basra including Nahran Omer and Al - Lahis oil fields in a period time of 6 months from August 2013 to January 2014. Mix cultures of (SRB) and (NRB) were isolated from these samples, the two types of bacteria were enumerated by using most probable number method, the results show that the numbers of both bacteria were generally quite low, the viable count of (SRB) was between 4 - 7cell/100 ml whereas the (NRB) was between <2 - 4 cell/100 ml. This study also includes purification of isolates for both (SRB) and (NRB) and the genetic identification by polymerase chain reaction (PCR) technique through which the universal 16S rRNA gene of 1500 bp is amplified and sequenced for identification to the level of strains. Microbial community analysis showed that isolates of (NRB) were have identity of 99% Pseudomonas stutzeri, P. putida, Herbaspirillum huttiense and Bacillus licheniformis while isolates of (SRB) were have identity of 99% Shewanella hafniensis, Desulfosporosinus orientis and Desulfotomaculum acetooxidans with supposing that all isolates new world strains. The results of the treatment with nitrate or nitrite showed a strong inhibitory effect on (SRB) growth and (H2S) production, sulfide levels do not increase at all concentrations (200, 400, 600, 800 and 1000) mg/l of nitrate or nitrite range between 4.2 - 21 mg/l in treatment with nitrate and 5.2 - 23 mg/l in treatment with nitrite. This is consistent with the concentrations of bacteria in all treatment bottles which range between 0.001 - 0.26 and 0.003 - 0.17 in treatment with nitrate or nitrite respectively, while there is a significant increase in sulfide 121 mg/l and concentration of bacteria 0.84 in control as optical density. (NRB) has a certain inhibitory effect on the growth of (SRB) and (H2S) production when the (NRB) nutrient (nitrate or nitrite 200, 400, 600, 800 and 1000) mg/l were adding , the activity of (NRB) increases after treatment, and it consumed all nitrate or nitrite during 2 - 3 days of incubation, the strong inhibition of (H2S) production is at concentration 1000 mg/l of nitrate where the results showed that there was significant decrease in sulfide level 34 mg/l and number of bacteria, 34.8 cell/ml during 10 days of incubation.Souring control at long term treatment in bioreactors show sharp decrease in production of (H2S) to 94% after injection of nitrate and nitrite during the period of 60 days, the continuous dosing of nitrate and nitrite (333 mg/l/day nitrate and 133 mg/l/day nitrite) inhibited the metabolic activity of (SRB) and (H2S) production severely, the sulfide levels decrease from 155 to 10 mg/l and number of (SRB) from >1100 to 3.5 cell/ml the percent in number decreased was to 99.6%, at the same time activity and numbers of (NRB) increase from 1100 to >1100 cell/ml over the duration of experiment. The results of corrosion rate measurement on mild steel after 60 days showed that the highest corrosion rate was 70.7 mg/cm2/year in control reactor while the lowest corrosion rate was 15.8 mg/cm2/year in treated reactor at the same period time of exposure with percent of decreasing in weight loss to 55% comparing with control reactor.

السيطرة الاحيائية واللااحيائية على نمو الفطر Aspergillus flavus والتعبير الجيني للجينين aflDو aflR وانتاج الافلاتوكسين B1 == Biotic and Abiotic Control on Aspergillus flavus Growth, aflD and aflR Expression and Aflatoxin B1 Production

اسم المؤلف: لبيد عبد الله نجم السعد
اسم المشرف: عدنان عيسى البدران | سامي عبد الرضا الجميلي
الموضوع العام: علوم الحياة
السنة: 2015
الموضوع الدقيق: التقنيات الاحيائية
الدرجة: دكتوراه
الجامعة: جامعة البصرة
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: Fifteen isolates of Aspergillus flavus (AFL1 - AFL15) were isolated from multiple sources included soil, compost, seeds, fruits, feed and air. The isolates were identified morphologically then confirmed by molecular techniques. Only thirteen isolates were confirmed positively (AFL1 - AFL5 and AFL8 - AFL15) while two of them were not. A phylogenetic analysis was made which revealed that the isolates grouped according to their source of isolation. The aflR profile and phenotypic AFB1 production confirmed that all thirteen isolates posses the ability to produce AFB1 with significant differences (P ≤ 0.05) among them. Growth rate profile was performed under 30ºC which showed significant differences (P ≤ 0.05) among isolates. According to the above tests, A.flavus AFL14 was selected to be the experimental isolate for the rest of experiments in this study. Comparing to A.flavus NRRL3357 type strain, the impact of temperature, water activity aw and isolate factors was examined to determine the limits and optimum ecological conditions of growth of A.flavus AFL14. The results displayed that the best growth rate was (7.217 mm/day) at 0.98 aw where the lowest was (4.069 mm/day) at 0.9 aw with no growth at 0.85 aw while the impact of temperature demonstrated by outweigh of growth rate at 35ºC (6.201 mm/day) followed by 30ºC (5.272 mm/day) which exceeded 25ºC and 40ºC (4.604 and 4.051 mm/day), respectively.Bacillus subtilis (isolates : BSS1, BSS2, BSS3, BSS4 and BSW) and Pseudomonas fluorescens (isolates : PFMst and PFDL) were elected to be used as biocontrol agents. All the isolates were passed the biochemical identification tests moreover, BSS4 and BSW isolates of B.subtilis and PFMst and PFDL isolates of P.fluorescens were confirmed molecularly which used later in all biocontrol experiments in this study. The ability ofbiocontrol agents to inhibit fungal growth was investigated and the resultsshowed significant inhibition impact represented by significant outweighof B. subtilis BSS4 (99%) on the rest of B. subtilis isolates followed by P.fluorescense PFDL and PFMst (92.29 and 86.19) %, respectively, with nosignificant differences (P ≤ 0.05) among them. The extra - cellular abilityof biocontrol agents to degrade AFB1 showed a high degradation abilityIpreformed by B. subtilis BSS4, BSW isolates and P. fluorescence PFMst,PFDL isolates (100, 100, 97.805 and 97.396%), respectively. Thedegradation residues administrated to rats to determine their effect onbiosystems, the blood parameters showed a significant reduction ofWBC, HB, RBC, and P.C.V while there was a significant increase inUrea, Glutamic pyruvate transaminase (GPT) Glutamic oxaloacetictransaminase (GOT) and MCV in AF+DMSO treatment comparing tothe negative and positive control. Water activity and biocontrol factorswere examined to control aflD and aflR expression and phenotypic AFB1production. When the experiment held using Nutrient Agar medium, asignificant inhibition of aflD and aflR expression (P=0.000 and 0.003),respectively performed by BSW at 0.94 aw comparing to 0.98 aw whileno significant inhibition was observed in the rest of the treatments. Allbiocontrol agents revealed high significant reduction of aflD and aflRexpression (P≤0.001) in each water activity level separately whichconfirmed by HPLC results. The phenotypic results showed that 0.94 awexceeded 0.98 aw in AFB1 reduction (2011 and 4280 ng/gm),respectively which agreed with gene expression results. When MaizeMeal Agar used as a medium, aflD expression presented a highsignificant increase at 0.98 aw relating to the NM level of each individualtreatment (P= 0.000 - 0.03) except PFDL+AFL14 which showed nosignificant aflD expression between both levels. aflR expression revealeda high significant reduction (P= 0. 000) caused by 0.98 PFDL+AFL14and 0.98 BSW+AFL14, respectively, while no significant differenceswere observed in the rest of the treatments or control. The HPLC resultsdisplayed a high significant reduction of AFB1 at 0.98 aw (8447 ng/gm)compared to (219000 ng/gm) at NM aw. The biocontrol agents caused ahigh significant reduction for both aflD and aflR expression (P=0. 000 - 0.043) under each individual water activity level while, HPLC resultsshowed non significant low reduction to the AFB1 performed by BSS4and BSW (25160 and 44790 ng/gm), respectively, followed by asignificant increase in AFB1 amount caused by PFMst and PFDL(267600 and 184100 ng/gm), respectively

واقع التلوث بالمركبات الهيدروكابونية في المياة والرواسب وبعض الاحياء المائية في مهر الكحلاء محافظة ميسان / العراق == The Status of Hydrocarbon Compounds Pollution of Water, Sediments and Some Aquatic Biota in Al - Kahlaa River - Missan Province /Iraq

اسم المؤلف: صالح حسن جازع
اسم المشرف: عبد الحسن يوسف العضب | حامج طالب السعد
الموضوع العام: علوم الحياة
السنة: 2015
الموضوع الدقيق: البيئة - التلوث البيئي
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: The present study was performed to have knowledge of hydrocarbon compounds pollution status in the water (dissolved and particulate fractions),sediments ,two species of aquatic plants (Ceratophyllum demersum and Paspalum pespaioides) ,two species of fishes(Liza abu and Carassius auratus) and one species of molluscs (Pseudodantopsis euphraticus) .The samples were collected monthly for the period November 2012 to October 2013 from four different stations ) Al - Magideh, Treatment unit, Al - Husaichi and Al - Zubair) distributed along Al - Kahlaa River in Missan province , in addition to Reference station lies on the Tigris River before entering Amara district about 25 Km .The sampling's months were divided into four typical seasons although this is incompatible with Iraq climate.As well as measures of some ecological parameters (water and air temperatures ,pH ,turbidity, electrical conductivity ,dissolved oxygen , biological oxygen demand BOD5 and total suspended solid) which ranged between 22 and 42 C˚ , 18 and 31 C˚ , 6.9 and 7.82 , 42 and 172 NTU , 12 and 118 μS/cm , 4.66 and 9.25 mg/l , 1.46 and 5.04mg/l ,33 and 108 mg/l respectively .In addition to that the Organic Matter(OM) and the texture were measured in the sediment samples. OM values ranged between 0.078 and 0.927% , whereas the percentage of the texture was ( 15 %clay, 71% silt and 14% sand),(31 %clay, 63% silt and 6% sand), (33 %clay, 57% silt and 10% sand) , (40 %clay, 47% silt and 13% sand) and (18 %clay, 55% silt and 27% sand) in Al - Magideh, Treatment unit , Al - Husaichi , Al - Zubair and Reference stations respectively .The concentrations of total petroleum hydrocarbons (TPHs)were measured by using spectrofluorometer. Concentrations of total petroleum hydrocarbons in dissolved fraction ranged between 1.36 μg/l in Reference station and 13.87 μg/l in Treatment unit station during summer and winter respectively ,and in particulate fraction between 2.69 μg/g dry weight in Reference station and 29.92 μg/g dry weight in Treatment unit station during summer and winter respectively ,while in sediments they ranged between 3.16μg/g dry weight in Reference station and 135.18 μg/g dry weight in Treatment unit station during summer and winter respectively. Concentrations of total petroleum hydrocarbons in C. demersum ranged between 5 μg/g dry weight during winter and 58.97 μg/g dry weight during summer , while in P. pespaioides between 3.18 μg/g dry weight during winter and 43.44 μg/g dry weight during summer. Concentrations of total petroleum hydrocarbons in L. abu ranged between 4.81 μg/g dry weight during spring and 37.3 μg/g dry weight during summer ,while in C. auratus between 2.51 μg/g dry weight during spring and 29.303 μg/g dry weight during autumn . Concentrations ofbtotal petroleum hydrocarbons in P. euphraticus ranged between 5.98 μg/g dry weight during spring and 119.75 μg/g dry weight during summer .The concentrations of Polycyclic Aromatic Hydrocarbons(PAHs) and n - alkanes were determined in the laboratories of Nihran Omer (South Oil Company in Basrah province ) ,using Gas Chromatography.Total concentrations of n - alkanes in dissolved fraction ranged between 0.027μg/l in Reference station and 0.192 μg/l in Al - Husiachi station during winter and between 0.016 μg/l in Reference station and 0.039 μg/l in Treatment unit during summer ,and for particulate fraction between 0.108 μg/g dry weight in Reference station and 2.096 μg/g dry weight in Treatment unit station during winter and between 0.101 μg/g dry weight in Reference station and 0.160 μg/g dry weight in Treatment unit station during summer ,while in sediments they ranged between 4.491 μg/g dry weight in Reference station and 51.32 μg/g dry weight Treatment unit station during winter and between 2.31 μg/g dry weight in Reference station and 19.31 μg/g dry weight in Treatment unit station during summer.The range of carbon chain length of n - alkanes in dissolved fraction ranged from C8 to C34 and in particulate fraction from C15 to C34 distributed in two patterns ,the first pattern included compounds between C8 and C25 with the abundance of C19,C21,C23 and C25 odd carbon number of and C18,C20,C22 and C24 for even carbon number ,while the second pattern included compounds with the range from C26 to C35 predominated by C27 and C29 odd carbon number and C26,C28 and C30 even carbon number.In sediments they ranged from C14 to C35 and distributed in two patterns, the first pattern included compounds between C8 and C25 with the abundance of C17,C19 and C21 odd carbon number and C18,C20 and C22 for even carbon number ,while the second pattern included compounds with the range from C24 to C35 with predominance of C31and C33 odd carbon number and from C24 to C34 even carbon number.Total concentrations of n - alkanes in C. demersum ranged between 6.467 μg/g dry weight during spring and 59.483 μg/g dry weight during summer ,whereas in P. pespaioides between 34.7 μg/g dry weight during winter and 166.6 μg/g dry weight during summer .The distribution of n - alkanes compounds in plants chain length ranged from C15 to C35 with bimodal from C15 to C27and from C28 to C35 with predominance of C17 to C25 odd carbon number and C18 to C24 even carbon number in the first one ,whereas in the second the dominance compounds were from C29 toC33 for odd carbon number and from C26 to C32 even carbon number.cTotal concentrations of n - alkanes in muscles of L. abu ranged between 14.60 μg/g dry weight during winter and 73.15 μg/g dry weight during summer and C. auratus between 34.76 μg/g dry weight during winter and 166.61 μg/g dry weight during summer . The distribution of n - alkanes compounds in fish muscles chain length ranged from C16 to C35 with bimodal from C16 to C25 and C26 to C35 with predominance of C17 to C25 and C18 to C24 for the first one ,and from C27 to C33 and from C26 to C34 for the second. These reflected nutrition nature for these kinds of fishes which depend on algae ,phytoplankton ,zooplankton ,diatoms ,insects and crustacean . While in the mollusc (P. euphraticus) ranged between 95.16μg/g dry weight during spring and 220.36 μg/g dry weight during summer. The distribution of n - alkanes compounds in P. euphraticus chain length ranged from C14 to C35 with bimodal from C14 to C27 and from C28 to C35 with predominance of C17 to C21 and from C18 to C24 for the first one ,and from C29 to C33 and from C30 to C34 for the second.The values of Carbon Preference Index (CPI) and pristane to phytane ratio was calculated to know the hydrocarbon compounds source in water ,sediments and biota of Al - Kahlaa River ,since the CPI value ranged between 0.142 and 1.314 in dissolved fraction and between 0.045 and 2.193 in particulate fraction , 0.160 and 1.872 in sediments,1.075 and 8.638 in plants , 0.285 and 1.537 in fishes and between 0.354 and 4.457 in mollusc .Whereas the values of pristane to phytane ranged between not detected and 1.579 in dissolved fraction , not detected and 0.601 in particulate fraction , 0.447 and 3.008 in sediments, not detected and 0.821 in plants , not detected and 2.176 in fishes and between 0.822 and 1.347 in mollusc .These indicate that there are two sources of hydrocarbon compound in water ,sediments and biota ,biogenic from living organisms and anthropogenic from domestic ,industrial and petroleum pollutants except in plants .Total concentrations of PAHs in dissolved fraction varied from 0.739 ng/l in Reference station to1.974 ng/l in Treatment unit during winter ,and from 0.300 ng/l in Reference station to1.125 ng/l in Treatment unit during summer ,and in the particulate fraction they varied from 0.79 ng/g dry weight in Reference station to 24.42 ng/g dry weight in Treatment unit during winter ,and from 4.369 ng/g dry weight in Reference station to10.545 ng/g dry weight in Al - Husaich during summer ,while in sediments they varied from 4.906 ng/g dry weight in Reference station to 35.479 ng/g dry weight in Treatment unit during winter ,and from 2.391 ng/g dry weight in Reference station to 25.886 ng/g dry weight in Treatment unit during summer.It had been noticed that there were a predominance of high molecular weight PAHs on low molecular weight PAHs ,while Benzo(a)dAnthracene/(Benzo(a)Anthracene+ Chrysene) BaA/(BaA+Chr) ratio ranged from 0.218 to 0.804 in water and 0.520 to 0.66 in sediments. The Indeno (1,2,3 - cd)pyrene /(Indeno (1,2,3 - cd)pyrene + Benzo(ghi)perylene) InP/(InP+BghiP) ratio ranged between not detected and 0.578 in water and between not detected and 0.681 in sediments .The Fluoranthene/ Pyrene (Fl/Py)ratio ranged between 0.150 and 2.47 in water and between 0.10 and 8.490 in sediments ,this give an indication of the source of PAHs compounds in water and sediments which were mainly pyrogenic and few from them petrogenic .Total concentrations of PAHs in C. demersum ranged between 24.124 ng/g dry weight during winter and 87.289 ng/g dry weight during summer ,whereas in P. pespaioides between 1.616 ng/g dry weight durig winter and 16.661 ng/g dry weight during summer .The Lower Polycyclic Aromatic Hydrocarbons to Higher Polycyclic Aromatic Hydrocarbons ratio ranged between 0.006 and 0.009 in C. demersum and between 0.008 and 0.103 in P. pespaioides. TheBaA/(BaA+Chr)ratio ranged from 0.995 to 0.997 in C. demersum and 0.756 to 0.995 in P. pespaioides. The InP/(InP+BghiP) ratio ranged between 0.342 and 0.807 in C. demersum and between 0.19 and 0.645 in P. paspaloides . The Fl/Py ratio ranged between 0.096 and 0.988 in C. demersum and between 0.018 and 5.018 in P. pespaioides. These indicate that the sources of PAHs in these plants were both pyrogenic and petrogenic .Total concentrations of PAHs in muscles of L. abu ranged between 2.301 and 16.661 ng/g dry weight during winter and summer respectively and in C. auratus between 1.095 and 8.675 ng/g dry weight during winter and summer respectively ,whereas in mollusc (P. euphraticus) ranged between 1.86 and 6.88 ng/g dry weight during spring and summer respectively. According to ratios of Low Polycyclic Aromatic Hydrocarbons(LPAHs) to High Polycyclic Aromatic Hydrocarbons (HPAHs), BaA/(BaA+Chr), InP/(InP+BghiP) and Fl/Py ,they certainly reflected that the PAHs sources in fishes and mollusk are pyrogenic as a main sources and petrogenic as a small part .Also results of this study revealed the presence of seasonal and spatial variations in concentrations of TPHs ,n - alkanes and PAHs in water ,sediments and aquatic biota from Al - Kahlaa River ,the highest concentrations were recorded during winter whereas the lowest during summer ,also the highest values of these compounds were recorded in Treatment unit station in comparison with other stations.

فصيلة الموديولات المتصالبة المنتهية اسقاطيا وبعض الازواج المترافقة للمقرنات التغايرية == Category of Profinite Crossed Modules and Some Adjoint Pairs of Covariant Functors

اسم المؤلف: شيماء عبد الرزاق عبد الله السباهي
اسم المشرف: رعد صالح مهدي الزركاني
الموضوع العام: علوم الرياضيات
السنة: 2013
الموضوع الدقيق: الرياضيات
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: كرست هذه الرسالة لتقديم ودراسة بعض الازواج المترافقة للمقرنات التغايرية بين فصيلة الموديولات المتصالبة المنتهية اسقاطيا وبعض الفصائل ذات العلاقة. الزوج المترافق الاول يتالف من المقرن المتناسي من فصيلة الموديولات المتصالبة المنتهية اسقاطيا الى فصيلة زمر التحويلات المنتهية اسقاطيا وكذلك المقرن المرافق الايسر من فصيلة زمر التحويلات المنتهية اسقاطيا الى فصيلة الموديولات المتصالبة المنتهية اسقاطيا حيث ان الاخير يوضح كيفية بناء موديول متصالب منتهي اسقاطيا من زمرة تحويلات منتهية اسقاطيا. الزوج المترافق الثاني يتالف من المقرن المتناسي من فصيلة الموديولات المتصالبة المنتهية اسقاطيا الحرة الى فصيلة التطبيقات المستمرة (من فضاءات منتهية اسقاطيا الى زمر منتهية اسقاطيا) وكذلك المقرن المرافق الايسر من فصيلة التطبيقات المستمرة الى فصيلة الموديولات المتصالبة المنتهية اسقاطيا الحرة حيث ان الاخير يوضح كيفية بناء موديول متصالب منتهي اسقاطيا حر على تطبيق مستمر من فضاء منتهي اسقاطيا الى زمرة منتهية اسقاطيا. اخيرا، تم دراسة الضرب المقابل (المضاد) في فصيلة الموديولات المتصالبة المنتهية اسقاطيا. | In this thesis, we introduce and study some adjoint pairs of covariant functors between the category of profinite crossed modules and some related categories. The first adjoint pair of covariant functors consists of the forgetful functor from the category of profinite crossed modules to the category of profinite transformation groups and the left adjoint functor from the category of profinite transformation groups to the category of profinite crossed modules, where the later one explains how to construct a profinite crossed module from a profinite transformation group. The second adjoint pair of covariant functors consists of the forgetful functor from the category of free profinite crossed modules to the category of continuous maps (from profinite spaces into profinite groups) and the left adjoint functor from the category of continuous maps to the category of free profinite crossed modules, where the later one explains how to construct a free profinite crossed module on a continuous map from a profinite space into a profinite group. Finally, we study the coproduct in the category of profinite crossed modules.

تحليل فيزيائي لاصوات العلة الانجليزية البسيطة في الكلام المتاني وكلام المحادثة == Acoustic Analysis of English Pure Vowels in Clear and Conversational Speech

اسم المؤلف: فراس فتحي علي الفاتح
اسم المشرف: حميد مجيد الحمادي
الموضوع العام: اللغات الاجنبية
السنة: 2010
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: البصرة
الصفحات الاولى:
المستخلص: Recently, the number of researchers and the amount of work in acoustic phonetics have greatly increased. This is because of the great importance that acoustic phonetics has on real life applications. Acoustic phonetics deals with those topics in experimental phonetics that can logically be investigated by the analysis, synthesis, and manipulation of speech. Acoustic phonetics can also be used to bridge the gaps that seem to separate phonetics from linguistics. Despite much research and discussion, the relation betweenacoustic properties and linguistic units remains debatable. However, acoustic phonetics with the aid of sophisticated computer programmes and language laboratories, can provide scientific and reliable results. It is especially for this reason that further progress in acoustic phonetics and linguistic structures is hoped for.The present study aims at conducting an acoustic analysis of BBC English pure vowels in two speaking styles. It aims at examining the acoustic properties of English pure vowels produced by native and nonnative speakers in clear and conversational speech. The present study concentrates on the most important aspects of acoustic phonetic research, acoustic analysis, vowel intelligibility, sex - related differences, as well as comparing clear with conversational speech. It is hypothesized that the acoustic properties of English pure vowels in conversational speech are different from those in clear speech. Moreover, the strategies employed by non - native speakers, i.e., exhibiting the acoustic characteristics of the vowels involved in both speaking styles, are different from those of native speakers. Previous work has provided some important insights into the field of acoustic research, particularly on clear and conversational speech. The current study follows the precise procedures presented by many investigators, particularly those procedures and techniques followed by Ferguson and Port (2002) as far as the work on speech styles and vowel intelligibility is concerned. Two recording sessions are conducted for both groups of talkers•Individual files are made for each vowel produced by each talker in both speaking styles. For the present study, vowel duration and values of fundamental frequency (F , i.e., the native and the non - native speakers. The first recording session is devoted to conversational speech analysis. The researcher has invited each talker to listen to a dialogue and talk in a normal conversational mode. The researcher has made sure to ask some questions that naturally evoke some target words.In the second recording session, the researcher asked each talker to read the selected target words (the carriers of the vowels) in a clear speaking style. The individual recordings are saved in a computer to be analysed using Praat’ which is a software for doing phonetics by computer.• The term Talkers’ is used, as advised by Prof. Sarah Ferguson, to refer to the people who come in and speak materials into a microphone.) are measured. Moreover, following Ferguson and Port (2002), the first two formants of the vowels produced by the talkers are measured at 50% of the vowel duration. Also, values of pitch range (maximum F0 - minimum F0) are calculated. Finally, vowel space areas based on the first two formants derived from each vowel in both speaking styles, are analysed and used for comparison. The results of the experiment revealed that all talkers, for both long and short vowels, produced longer vowel durations, higher values of F0, greater values of pitch range, and larger vowel space areas in clear than in conversational speech. Nearly all female talkers in both groups produced higher values than male talkers as far as the four acoustic measures are concerned. Notably, the findings of this study have also shown that the strategies employed by non - native speakers in exhibiting the acoustic properties of English pure vowels, are different from those of native speakers. Moreover, according to the results, clear speech is more intelligible than conversational speech. In an attempt to make themselves, more intelligible or understandable, most talkers produced the vowels more slowly, more loudly, and in a very careful manner, regardless of their language background. In regard to recommendations and suggestions, the researcher has given some recommendations and has also suggested some important points for further research.
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