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Article
Recovery of Cobalt and Lithium from Spent Lithium Ion Batteries

Authors: N.E. Abdul Latif --- A.M. Ahmed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2017 Volume: 35 Issue: 2 Part (A) Engineering Pages: 139-148
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this research a combination of mechanical separation, reductive leaching and chemical precipitation are used to regain Li as Li2CO3 and Co as Co(OH)2 from waste lithium ion batteries. First batteries are dismantled and different component are separated. Anode and cathode foils are grinded and sieved to extract Al and Cu from spent battery powder. The separation efficiency for copper and aluminum are 97.68% and 84.41% respectively. The separated powder is leached with sulfuric acid and hydrogen peroxide solution to dissolve cobalt and lithium. The effects of sulfuric acid concentration, time, temperature, concentration of hydrogen peroxide and S/L on the leaching efficiency for cobalt and lithium are studied. Design of experiments by Taguchi method is used to determine experiments conditions, analysis the results, and identify the optimum leaching conditions. The optimum leaching conditions are 1.5 M acid concentration, 60 minute, 60 °C, 15% H2O2, and 40 g/l solid to liquid ratio. Leaching efficiencies of 94.07% Co and 98.15% Li are achieved with these optimum conditions. Leaching solution of the optimum experiment is used to recover cobalt as cobalt hydroxide and lithium as lithium carbonate by chemical precipitation. An equivalent volume of 4M NaOH is used to precipitate cobalt as cobalt hydroxide. After 1 hour 99.98%, Co is precipitated and collected by filtration and dried. After collection of the Co(OH)2 product, the remaining solution is treated with equivalent volume of "saturated solution" of Na2CO3 at 100 °C to recover lithium as Li2CO3. After 1 hour, 80 – 85 % Li is precipitated, filtrated and dried. Precipitation products are investigated with XRD, which confirmed that cobalt hydroxide and lithium carbonate are recovered from leaching solution.


Article
Generation of Femtosecond Pulses from Order-of-Magnitude Pulse Compression in a Synchronously Pumped Optical Parametric Oscillator Based on Periodically Poled Lithium Niobate

Author: L. Liforte
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2006 Volume: 2 Issue: 3-4 Pages: 24-26
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

We demonstrate the generation of compressed, transform-limited 250-fs pulses, tunable in the near infrared, by means of synchronously pumped optical parametric oscillation in periodically poled lithium niobate. The almost 20-fold compression from the 4-ps pulse duration of the cw mode-locked Nd:YLF pump results in signal peak powers well in excess of the pump power.


Article
Dielectric properties of Li doped Ni-Zn ferrite
الخصائص الكهربائية للنيكل زنك فرايت المشوب بالليثيوم

Authors: Mukhlis M. Ismail مخلص مولود اسماعيل --- Nasma A. Jaber نسمة عدنان جبر
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2018 Volume: 16 Issue: 36 Pages: 140-152
Publisher: Baghdad University جامعة بغداد

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Abstract

Lithium doped Nickel-Zinc ferrite material with chemical formula Ni0.9−2x Zn0.1LixFe2+xO4, where x is the ratio of lithium ions Li+ (x = 0, 0.01, 0.02, 0.03 and 0.04) prepared by using sol-gel auto combustion technique. X-ray diffraction results showed that the material have pure cubic spinal structure with space group Fd-3m. The experimental values of the lattice constant (aexp) were decreased from 8.39 to 8.35 nm with doped Li ions. It was found that the decreasing of the crystallite size with addition of lithium ions concentration. The radius of tetrahedral (rtet) and octahedral (roct) site were computed from cation distribution. SEM images have been taken to show the morphology of compound. The dielectric parameters [dissipation factor (Df), the dielectric constant (Ԑ') and a.c. conductivity (σac)] of spinal ferrite nano-powder have been measured. The dielectric parameters as a function of concentration have been studied for ferrite synthesis. The saturation of magnetization (Ms), remiensis (Mr) and coersivity (Hc) were found from hysteresis loop. The Ms and Hc varied from 36.47 to 66.15 emu/gm and 103 to 133 Oe for ferrite synthesis, respectively.

تم تحضير نيكل-زنك فرايت المشوب بأيونات الليثيوم باستخدام تقنية الاحتراق التلقائي (sol-gel auto combustion). من طيف الاشعة السينية تم حساب القيم العملية لثابت الشبيكة (aexp) حيث وجد انه يقل مع إضافة ايونات الليثيوم بالإضافة الى النقصان في حجم البلورة. تم دراسة الخصائص الكهربائية كدالة للتردد ولقد وجد ان ثابت العزل والتوصيلية تقل مع زيادة التردد لكل العينات. لكن عند دراستها كدالة للتركيز فقد وجد ان هذه القيم تزداد مع اضافة الليثيوم. من حلقة الهسترة تم تحديد تمغنط الاشباع MS وحساب القيم العملية والنظرية لعزوم التمغنط.


Article
Evaluation of the effect of surface treatments on shear bond strength between lithium disilicate ceramic and dentin

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Abstract

Purpose: To evaluate the effect of different surface treatments on shear bond strength between dentin and IPS e.max lithium disilicate glass-ceramic.Materials and Methods: Eighteen extracted third molars were embeded in epoxy resin. The tooth was sectioned vertically in mesiodistal direction using a low speed hard tissue microtome. The buccal and lingual surfaces of each section were ground flat using 600 grit Silicone carbide paper. Eighteen ceramic discs consisted of lithium disilicate glass-ceramic were prepared with a diameter of 4.7mm and height of 2.2mm. The discs were divided in two groups (n=10): (1) IPS e.max treated with hydrofluoric acid and Monobond Plus (MBP) and (2) IPS e.max treated with Monobond Etch &Prime (MBEP). The tooth was cemented with Multilink Automix and stored for 24hours at room temperature before thermocycling and subsequently loaded to failure in Universal Testing Machine. Failure mode were recorded for each specimen.Result: Bond strength analysis and t-test analysis MBEP demonstrated the higher shear bond strength (SBS). MBP and MBEP showed no statistically significant difference were found between them. One-way ANOVA and t-test was used to determine differences in bond strength within and between the groups. Cohesive failure in resin cement was predominant with higher results while adhesive and mixed with lower and equal.Conclusion: Surface treatment with Monobond Etch and Prime has a favorable effect on SBS between dentin and lithium disilicate glass-ceramic with resin cement compared with Monobond Plus.


Article
Effects of Different Core Thickness on The Microhardness of Lithium- Disilicate Glass Ceramic

Authors: Ihab Naffea Yassen --- Nawras Adnan Mohammed
Journal: Journal of Oral and Dental Research مجلة طب الفم والاسنان ISSN: 23106417 Year: 2019 Volume: 6 Issue: 1 Pages: 51-58
Publisher: Iraqi Association for Oral Research الجمعية العراقية لبحوث طب الفم

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Abstract

Lithium disilicate is the major crystal phase, and be composed of needle-resemble crystals. These crystals are measured from 3 to 6 μm in length. In general, E.maxpress properties are very slightly uppermost crystals found in E.max-CAD because of the larger and longer crystals. Due to the materials that have different firing temperatures (820⁰C for E.max-press). The objective of this study is to estimate the effect of various thickness on the hardness of a sample prepared by lithium disilicate glassceramic material.Materials and methods Thirty disc-shaped wax patterns wereprepared with three core thickness of (0.5mm, 1mm and 1.5mm). All the specimens fabricated with 10mm in diameter and designed according to the ISO specification 6872. Vickers diamond indenter has widely utilized in this study in accordance with the micro-hardness tester device. Results The present data were analyzed statistically using SPSS (V-22). One-way ANOVA and (LSD) test show that the mean values of 0.5mm core thickness was of 800(±120), while the mean value of 1mm core thickness was of 1229 (±139), and that of 1.5mm core thickness was 1117(±221).Conclusions the results showed that the lithium disilicate glass ceramic material had more advanced surface hardness at thickness of 1mm than that of 0.5mm and 1.5mm thickness of the same materials.


Article
Distribution of some Chemical Elements in the Marsh Lands of Southern Iraq After Rehabilitation

Author: R S. Adam I J. M. Al-ShawiF J. M. Al-Imarah
Journal: Marsh Bulletin مجلة الاهوار ISSN: 18169848 Year: 2007 Volume: 2 Issue: 1 Pages: 11-17
Publisher: Basrah University جامعة البصرة

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Abstract

This study included the determination of Ten chemical elements: Aluminum, Arsenic, Calcium, Copper, Iron, Lead, Lithium, Magnesium, Mercury and Zinc in water of 12 sites from southern Iraqi marshland. Recorded Calcium and Magnesium values were the highest in the range (5.1- 12.4) and (33.8 – 41.8)mg/l respectively, and higher in Al-Izz river of Central Marsh. Iron in the concentration of 0.02 mg/l was recorded in Al-Izz river of central marsh and Al-Tarabah village of Al-Hawiezah marsh only. Zinc is distributed widely in Iraqi marshes, the highest recorded value for Zn was in Hor Abu-Ijel which reached 0.61 mg/l. Copper was in a lower concentrations and reported values in certain places only with the highest value of 0.02 mg/l in Um- Nakhlah. Mercury and Aluminum each were recorded in one site, 0.11 mg/l Mercury in Al-Izz river and 13 mg/lAl in South of Al-Hawiezh marsh. Lead, Lithium, and Arsenic were absent in this study.


Article
Optimization of Solar-Driven of a small Absorption Air Conditioning System- eng
أمثلية لمنظومة تكييف امتصاصية صغيرة تعمل بالطاقة الشمسية

Authors: Dr. A.S. Dawood د.أمير سلطان داوود --- H. A.Yousif حسين أزهر يوسف
Journal: AL Rafdain Engineering Journal مجلة هندسة الرافدين ISSN: 18130526 Year: 2013 Volume: 21 Issue: 4 Pages: 42-56
Publisher: Mosul University جامعة الموصل

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Abstract

AbstractThis research deals with the optimum design of an absorption cooling system with cooling capacity of 2 ton refrigeratio driven by solar energy and using Lithium Bromide as absorbent and Water as refrigerant. The present system uses water for cooling the absorber, condenser and for heat transfer in the evaporator. A mathematical model is built to simulate a solar collector system and absorption system, in addition to design flat plate solar collector, f-chart method is used to find the optimum required solar collector area to air condition a space in the establishment with eight hour per working day. The coefficient of performance (COP) has been taken as a measurement to find the optimum internal operation conditions, by examining the performance of absorption system with varying temperatures to the generator, absorber, condenser, evaporator and effectiveness of a solution heat exchanger to obtain the optimum values of these operation conditions and also obtain maximum value of the COP. The result show that the collector area has a large effect on the actual useful heat gain and auxiliary heat to the system, and a collector area 26m2 is enough to operate absorption system more than eight hours by using a water storage tank with a capacity of 1.5 m3 and depending on weather data of Mosul city. The results also show that the generator temperature had a great effect on the absorption and solar collector systems. Keywords: absorption system, solar energy, water- lithium bromide solution, air conditioning, optimization.

الخلاصة يتضمن البحث دراسة التصميم الأمثل لمنظومة تبريد امتصاصية سعة2 طن تعمل بالطاقة الشمسية وتستخدم بروميد الليثيوم بوصفه مادة ماصة و الماء بوصفه مائع تبريد. ويستخدم الماء بوصفه وسيطاً لتبريد المكثف ووعاء الامتصاص, كما ويستخدم أيضا كونه وسيطاً لانتقال الحرارة في المبخر وقد تم بناء نموذج رياضياتي لمحاكاة منظومة المجمع الشمسي والمنظومة الامتصاصية, فضلاً عن تصميم المجمع الشمسي من نوع الصفيحة المستوية , إذ اعتمدت طريقة مخطط الكسر الشمسي؛ لإيجاد المساحة المثلى للمجمع الشمسي واللازمة لتكييف صالة في إحدى المؤسسات تعمل لمدة ثمان ساعات يومياً. وتم أخذ معامل أداء المنظومة الامتصاصية بوصفه مقياساً في تحديد ظروف التشغيل الداخلية المثالية, وذلك باختبار أداء المنظومة الامتصاصية عند تغير ظروف التشغيل التي هي درجات الحرارة لكل من المولد, ووعاء الامتصاص, والمكثف, والمبخر, وفعالية المبادل الحراري للمحلول, وبالتالي الحصول على أمثل قيم لمتغيرات الإدخال المذكورة, وكذلك الحصول على أعلى قيمة لمعامل الأداء. وأظهرت النتائج أن مساحة المجمع الشمسي لها تأثير كبير في قيمة الطاقة الحقيقية المفيدة, وفي قيمة الطاقة المضافة لمنظومة المجمع الشمسي , وتبين أن مساحة المجمع26m2كافية لتشغيل المنظومة الامتصاصية سعة 2 طن لأكثر من ثمان ساعات يوميا باستخدام خزان ذي سعة 1.5 m3 وفق بيانات المناخ لمدينة الموصل . كما أن درجة حرارة المولد تؤثر في المنظومتين الامتصاصية والمجمع الشمسي.


Article
Potential Energy Expectation Value for Lithium Excited State (1s2s3s)
القيمة المتوقعة لطاقة الجهد لحالة الليثيوم المتهيجة والايونات المشابهة لها (Be+,B+2)

Authors: Khalil H. Al-Bayati خليل هادي البياتي --- Nasma G. Hussein نسمة جبار حسين --- Ban H. Adel بان حسن عادل
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2015 Volume: 12 Issue: 2 Pages: 394-399
Publisher: Baghdad University جامعة بغداد

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Abstract

The purpose of the present work is to calculate the expectation value of potential energy for different spin states (ααα ≡ βββ,αβα ≡ βαβ) and compared it with spin states (αββ , ααβ ) for lithium excited state (1s2s3s) and Li- like ions (Be+,B+2) using Hartree-Fock wave function by partitioning techanique .The result of inter particle expectation value shows linear behaviour with atomic number and for each atom and ion the shows the trend ααα < ααβ < αββ < αβα .

إن الغرض من العمل الحالي هو حساب القيمة المتوقعة لطاقة الجهد لحالات البرم المختلفة (ααα ≡ βββ,αβα ≡ βαβ) ومقارنتها مع حالات البرم (αββ , ααβ ) لحالة الليثيوم المتهيجة (1s2s3s) والايونات المشابهة لها (Be+,B+2) باستعمال الدالة الموجية هارتري-فوك بإستخدام تقنية التجزئة . ونتيجة القيمة المتوقعة للمسافة البينية يظهر السلوك الخطي مع العدد الذري ومع كل ذرة وآيون فأن يظهر الاتجاه (αβα > ββα > βαα > ααα ).


Article
Fracture strength of laminate veneers using different restorative materials and techniques (A comparative in vitro study)

Authors: Abeer Gh. Abdul Khaliq --- Inas I. Al-Rawi ايناس الراوي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2014 Volume: 26 Issue: 4 Pages: 1-8
Publisher: Baghdad University جامعة بغداد

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Background: Esthetic correction represents one of the clinical conditions that required the use of laminate veneers inpremolars region. Aim of the study: The purpose of this study was to evaluate the fracture strength of the laminateveneers in maxillary first premolars, fabricated from either composite (direct and indirect techniques) or ceramicCAD/CAM blocks.Materials and Methods: Fifty sound human maxillary premolar teeth were used in this in vitro study. Teeth weredivided randomly into one control group and four experimental groups of ten teeth each; Group A: Restored withdirect composite veneer (Filtek Z250 XT), Group B: Restored with indirect composite veneers (Filtek Z250 XT), Group C:Restored with lithium disilicate ceramic CAD/CAM blocks (IPS e. max CAD) and Group D: Restored with resin nanoceramic CAD/CAM blocks (Lava Ultimate Restorative). Standard preparations were done using Ceramic Veneer Set(Komet). Indirect laminate veneers were cemented with the Relyx Veneer Cement (3M ESPE) and all specimenswere stored in distilled water at 37°C for 2 weeks. The load was applied on the occlusal part of the veneer at 45˚ tolong axis of the tooth using universal testing machine. Results were analyzed with one-way ANOVA and LSD tests.Specimens were examined by stereomicroscope at a magnification of 20x to evaluate the mode of failure.Results: Control group showed higher mean of fracture strength with highly significant difference in comparison tothe experimental groups (P<0.01). (Group A) showed higher mean of fracture strength with statistically significantdifference in comparison to (Group B and Group D). On the other hand the difference between (Group A andGroup C) was statistically highly significant. Statistically non-significant difference was found among the threeindirectly restored groups.Conclusions: All veneers used in this study can be considered as acceptable treatment in the premolars region forpatients with normal biting force. Direct composite veneer is the most favorable technique in term of fracturestrength, while IPS e. max CAD laminate veneers were least likely to fracture and most likely to completely debond

یمثل التصحیح التجمیلي واحدة من الحالات السریریة التي تتطلب استخدام القشور التجمیلیة في المنطقة الضواحك العلویة. الغرض من ھذه الدراسة كان لتقییم قوة كسر القشور.CAD / CAM التجمیلیة في أسنان الضواحك, مصنوعة من المواد المركبة أو من قوالب السیرامیك باستخدام ثلاثة طرق مختلفة: المباشرة, الغیر المباشرة و باستخدام تقنیة التم اختیار خمسین سنا من الضواحك العلویة لاشخاص بالغین ، تم تقسیم الأسنان بشكل عشوائي في خمس مجامیع؛ مجموعة قیاسیة و أربع مجموعات تجریبیة (عشرة أسنان لكلالمجموعة (ب): رممت ,(Filtek Z250 XT, 3M ESPE) منھم)؛ المجموعة (أ) :رممت باستخدام القشور التجمیلیة مصنوع من المادة المركبة بصورة مباشرة على الاسنانالمجموعة (ج): رممت باستخدام القشور (Filtek Z250 XT, 3M ESPE) باستخدام القشور التجمیلیة مصنوع بطریقة غیر مباشرة على قالب الحجر باستخدام المادة المركبةو المجموعة (د): رممت باستخدام قشور تجمیلیة مصنوعة من قوالب (IPS e. max CAD, Ivoclar Vivadent) التجمیلیة المصنوعة من قوالب سیرامیك اللیثیوم ثنائي السیلیكاتCEREC inLab ) CAD / CAM في المجموعتین (ج و د), تم صناعة القشور التجمیلیة باستخدام تقنیة ال .(Lava Ultimate Restorative, 3M ESPE) راتنج نانو سیرامیكتم تثبیت تعویضات .(Ceramic Veneer Set) 4.02 )..وقد تم عمل التحضیرات القیاسیة ( داخل المینا) لكل الاسنان في المجامیع التجریبیة باستخدام , milling system, Sironaلمدة اسبوعین ˚ المتصلب بالاشعة الضوئیة وخزنھا بالماء المقطر بدرجة حرارة 37 (Relyx Veneer Cement) القشور التجمیلیة الغیر مباشرة باستخدام السمنت المركب الرانتیجيLSD ) واختبار اقل فرق معنوي (ANOVA) تم تحلیل النتائج احصائیا باستخدام اختبار .(Universal testing machine) قبل اجراء فحص قوة الكسر باستخدام جھاز الاختباروقد تم فحص العینات الفاشلة تحت المجھر لتحدید نمط الفشل. في الختام استنتادا الى نتائج ھذه الدراسة, یمكن استخدام القشور التجمیلیة للاسنان الضواحك العلویة ولكن .(testاستخدامھ للمریضمع خطأ في أداء الوظیفة الاطباقیة ینبغي تقییمھبعنایة. القشور التجمیلیة المصنوعة من المركب الراتنیجي بالطریقة المباشرة ھو الأسلوب الأكثر ملاءمة من حیث قوةالكسر في الضواحك.


Article
Failures of Porcelain Laminate Veneers Using Different Techniques of Bonding, A Comparative Study

Authors: Safa Adnan Gaeed --- Prof. Ammar Atta-Allah Ali
Journal: Journal of Oral and Dental Research مجلة طب الفم والاسنان ISSN: 23106417 Year: 2017 Volume: 4 Issue: 1 Pages: 35-46
Publisher: Iraqi Association for Oral Research الجمعية العراقية لبحوث طب الفم

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