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Article
Solvent- Free Synthesis and Spectroscopic Identification of Some Chalcones and Imines Derived From p-Amino acetophenone
التشيد و التشخيص الطيفي لبعض مركبات الجالكون و الأيمينات المشتقة من بارا-امينو اسيتوفينون بدون استخدام المذيب

Author: Farouq E. Hawaiz فاروق امام حويز
Journal: Tikrit Journal of Pure Science مجلة تكريت للعلوم الصرفة ISSN: 18131662 Year: 2010 Volume: 15 Issue: 2 Pages: 78-86
Publisher: Tikrit University جامعة تكريت

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Abstract

Two series of Chalcones (3a-j) and Imines (4a-j) have been synthesized in high yield via simple and convenient solvent- free process from the same starting material p-amino acetophenone with different substituted benzaldehydes(2a-j) by using the catalysts sodium hydroxide and acetic acid respectively. The structure of the synthesized compounds were elucidated spectroscopically using FT-IR, 1H-NMR, 13C-NMR and 13C-Dept- 135 spectra

بطريقة مبسطة وملائمة وبدون استخدام المذيب (4a-j) والايمينات (3a-j) تم تحضير سلسلتين من الجالكونات مع معوضات مختلفة للبنزالديهايد باستخدام عاملين بارا-امينو اسيتوفينون من نفس المواد الاولية المستخدمة مساعدين مختلفين هيدروكسيد الصوديوم وحامض الخليك على التوالى. تراكيب المركبات المحضرة تم تشخيصها طيفيا باستخدام اطياف 13C-Dept 135 و 13C-NMR، 1H-NMR ، FT-IR .

Keywords

solvent free --- chalcones --- imines


Article
Experimental Investigation on Factors Affecting Oil Recovery Efficiency during Solvent Flooding in Low Viscosity Oil Using Five-Spot Glass Micromodel

Authors: Mohsen Safari --- Mohammad Parvaz Davani --- Hamed Hematpur
Journal: Journal of Petroleum Research & Studies مجلة البحوث والدراسات النفطية ISSN: 22205381 Year: 2014 Volume: 377 Issue: 10th Pages: 205-222
Publisher: Ministry of Oil وزارة النفط

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Abstract

Lack of experimental study on the recovery of solvent flooding in low viscosity oil is obvious in previous works. This study concerns the experimental investigation on oil recovery efficiency during solvent/co-solvent flooding in low viscosity oil sample from an Iranian reservoir. Two micromodel patterns with triangular and hexagonal pore structures were designed and used in the experiments. A series of solvent flooding experiments were conducted on the two patterns that were initially saturated with crude oil sample. The oil recovery efficiency as a function injected pore volume was determined from analysis of continuously captured pictures. Condensate and n-hexane were employed as base solvents, and Methyl Ethyl Ketone (MEK) and Ethylene Glycol Mono Butyl Ether (EGMBE) used as co-solvents. The results revealed that not only does the solvent flooding increase the recovery in low viscosity oil but also this increase is evidently higher with respect to viscous oil. But, type of solvent or adding co-solvent to solvent does not noticeably increase the recovery of low viscosity oil. In addition, further experiments showed that presence of connate water or increasing injection rate reduces the recovery whereas increasing permeability improves the recovery. The results of this study are helpful to better understand the application of solvent flooding in low viscosity oil reservoirs.


Article
The Effect of Solvent Extraction of Light Lubricating Oilon Viscosity Index and Chemical Composition

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Abstract

An investigation was conducted for the improvement of viscosity index of light lubricating oil fraction (40 stock) obtained from vacuum distillation unit of lube oil plant of Daura Refinery, using solvent extraction process.In this study furfural solvent was used to extract the undesirable materials which reduce the viscosity index of raw lubricating oil fraction.The studied effecting variables of extraction were extraction temperature range from 70 to 110°C, and solvent to oil ratio range from 1:1 to 4:1 (wt/wt).The n-d-M method was used for calculation of carbon distribution and structural group analysis of the raffinate produced from furfural extraction.Also the three component phase diagram for a mixed-base oil and furfural at different temperature was drawn.The results of this investigation show that the viscosity index of lubricating oil fraction increases with increasing extraction temperature and increasing the solvent to oil ratio and reaches 115.6 at extraction temperature 110°C and solvent to oil ratio 4:1.Further more, the results show that the viscosity, refractive index, density, sulfur content and percentage yield of produced raffinate were decreased as the extraction temperature or solvent to oil ratio increases for extraction process.


Article
Spectrophotometric Determination of Micro Amount of Copper (II) in Different Enviromental and Vital Samples by New Organic Reagent

Authors: Shawket K. Jawad شوكت كاظم جواد --- Senaa K. Ali --- Safa M. Hameed
Journal: Iraqi National Journal Of Chemistry المجلة العراقية الوطنية لعلوم الكيمياء ISSN: 22236686 Year: 2011 Issue: 43 Pages: 299-309
Publisher: Babylon University جامعة بابل

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Abstract

Abstract 2-[4-Chloro-2-methoxy phenyl azo]-4,5-diphenyl imidazole used as a new complexing organic reagent for extraction and determination of copper (II) in different samples include plants leaves, soil and water from different position in Al-Najaf governorate as well samples of human serum, cow liver and kidney, vitamins and spices. All these measurement carried out at the optimum condition for complexation reaction. Beer's law is obeyed over the concentration rang 0.5-30µg/mL with a detection limit 8×10-5 µg.mL-1 and molar absorptivity 8459.79L.mole-1.cm-1. Sandell’s sensitivity 7.5×10-8µg.cm-2.

الخلاصة 2-[4-كلورو-2-ميثوكسي فنيل ازو]-4,5- ثنائي فنيل اميدازول استخدم ككاشف تعقيد عضوي جديد لاستخلاص وتقدير النحاس (II) في نماذج مختلفة تضمنت أوراق النباتات، التربة، المياه من مناطق مختلفة في محافظة النجف الأشرف وكذلك نماذج مصل دم الإنسان، كبد وكلية البقر فضلا عن بعض الفيتامينات والتوابل. وكل هذه القياسات تمت تحت الظروف المثلى لتفاعل التعقيد. المطاوعة لقانون بير كانت في حدود التراكيز 0.5-30µg/mL وكان حد الكشف 8×10-5 µg.mL-1 وقيمة الامتصاصية المولية 8459.79L.mole-1.cm-1. حساسية ساندل 7.5×10-8µg.cm-2.


Article
With Solvent Extraction Method, and via new Organic Reagent 2-(Benzo thiazolyl azo)-4,5- Diphenyl Imidazole for Spectrophotometric Determination of Copper (II) in different Samples
بواسطة طريقة الاستخلاص بالمذيب وباستخدام الكاشف العضوي الجديد 2-[بنزوثيازوليل ازو]-5,4-ثنائي فنيل اميدازول للتقدير الطيفي للنحاس (II) في نماذج مختلفة

Authors: Sahar Aqeel Hussein سحر عقيل حسين --- Safa Mageed Hameed صفا مجيد حميد --- Shawket Kadhim Jawad شوكت كاظم جواد
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2014 Volume: 11 Issue: 1 Pages: 147-157
Publisher: Baghdad University جامعة بغداد

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Abstract

The new organic reagent 2-[Benzo thiazolyl azo]-4,5-diphenyl imidazole was prepared and used as complexing agent for separation and spectrophotometric determination of Cu2+ ion in some samples include plants, soil, water and human blood serum. Initially determined all factors effect on extraction method and the results show optimum pH was (pHex=9), optimum concentration was 40μg/5mLCu2+ and optimum shaking time was (15min.), as well stoichiometry study appears the complex structure was 1:1 Cu2+: BTADPI. Interferences effect of cations were studied. Synergism effect shows MIBK gave increasing in distribution ratio (D). Organic solvent effect appears there is no any linear relation between dielectric constant for organic solvent used and distribution ration (D). Thermodynamically found the reaction was Endothermic reaction, with ΔHex= 0.0131 KJ.mole-1,ΔGex=-54.20 KJ.mole-1 ,ΔSex= 167.84 J.mole-1.Beer’s law was obeyed over the concentration 1-30μg/5mL, and ε=922.90 Lmol-1.cm-1,with detection limit 1.7×10-5and Sandell’s sensitivity 6.8× 10-7 gcm-2.

الكاشف العضوي الجديد 2-[بنزوثيازوليل آزو]-4,5- ثنائي فنيل اميدازول تم تحضيره واستخدم ككاشف عضوي للفصل والتقدير الطيفي لأيونات النحاسCu2+ في نماذج مختلفة تضمنت عينات نباتية وتربة ومياه ومصل دم الإنسان. وفي البداية تم تحديد كافة العوامل المؤثرة على عملية الفصل وإشارات النتائج إلى أن الدالة الحامضية المثلى لعملية الاستخلاص كانت (pHex=9)والتركيز الأمثل لأيونCu2+ في المحلول المائي40μg/5mL وزمن الرج الأمثل (15دقيقة). أما دراسة التركيب الأكثر احتمالاً أظهرت أن تركيب المعقد كان 1:1 Cu2+: BTADPI. كما تم دراسة تأثير التداخل للأيونات الموجبة ودراسة تأثير توليف المذيبSynergism بينت أن MIBK أعطى ارتفاعاً في نسب التوزيع(D) أما دراسة تأثير المذيب العضوي أظهرت عدم وجود أي علاقة خطية بين ثابت العزل الكهربائي(ε) للمذيبات العضوية المستخدمة وقيم نسب التوزيع(D) وفي الجانب الثرموديناميكي للدراسة فقد أظهر أن التفاعل كان ماص للحرارةEndothermic reaction وقيم الدوال الثرموديناميكية كانتΔHex= 0.0131 KJ.mole-1, ΔGex=-54.20 KJ.mole-1, ΔSex= 167.84 J.mole-1.وكانت المطاوعة لقانون بير في مدى التركيز μg/5mL30-1 وقيمة الامتصاصية المولية كانت 922.90Lmol-1cm-1وإن حد الكشف هو 1.7×10-5mgL-1. أما حساسية ساندل فكانت -7gcm-210×6.8.


Article
Crude Oil Desalting Using Multi-Surfactant Based on a Best Dosage, Solvent and Mixing Ratio

Authors: Ali Hussein Khalaf --- Mohammed Salah Rajab
Journal: Tikrit Journal of Engineering Sciences مجلة تكريت للعلوم الهندسية ISSN: 1813162X 23127589 Year: 2019 Volume: 26 Issue: 2 Pages: 23-27
Publisher: Tikrit University جامعة تكريت

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Abstract

Crude oil desalting is the first processing step in a refinery. The objectives of crude desalting are the removal of salts, solids, and the formation of water from unrefined crude oil before the crude is introduced in the crude distillation unit of the refinery. The experimental work is divided into three schemes covering the effect of surfactant dosage, test different types of surfactants, and the effect of salt content on desalting efficiency. The results show that the crude oil desalting efficiency, increased with increasing surfactant quantity., The results indicate that desalting efficiency has lowered with increasing the salt content in crude oil. Also, the results show that the best solvent was toluene, and the best mixing ratio of solvent was 10 Vol. %.


Article
Preparation, Infra-red and solvent effects On the Electronic absorption spectra of Magnesium Phthalocyanine

Author: JABBARS.HADI
Journal: Misan Journal of Acodemic Studies مجلة ميسان للدراسات الاكاديمية ISSN: 1994697X Year: 2012 Volume: 11 Issue: 20 Pages: 13-18
Publisher: Misan University جامعة ميسان

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Abstract

Abstract:Magnesium Phthalocyanine (abbreviated MgPc) like othermethallophthalocyanines have limited solubility in most solvents this behaviourprevented complete spectroscopic studies. In this paper MgPc was prepared andInfra-red peaks were characterized, and MgPc has been found to be soluble inseveral solvent (DMF, DMSO, THE, Pyridine and Chlorobenzene). The studyshow that tlie position of Q-band show very small change in non aromatic solventDMF, DMSO and THF. The blue shift was observed in aromatic solvent(chlorobenzene, this is because of the aggregation of MgPc molecules and theaggregation increase as the concentration increase. In pyridine a red shift of Qbandwas observed.


Article
A study of the solvent effect on the low temperature spectra of benzoanthracene molecules
دراسة تاثير المذيب على اطياف درجات الحرارة الواطئة لجزيئات البنزوانثراسين

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Abstract

Low temperature spectroscopy of benzoanthracene solutions at fixed molar concentration has been studied. The temperature range has been taken at room temperature down to liquid nitrogen temperature (77K). Polar and nonpolar solvents have been used to study the solvent effect on the absorption and fluorescence spectra of solute molecules. Some of the spectroscopic parameters have been determined as functions of solvent polarity and temperature. The results indicate that the band width FWHM increases with increasing the solvent polarity and temperature, while the peak emission cross section decreases with increasing of solvent polarity and decreases with increasing the temperatures. Clear vibrational structure spectra of benzoanthracene molecules have been observed in Nonane and Hexane solvents at 77K.

في العمل الحالي تم دراسة مطيافية درجات الحرارة الواطئة لجزيئة البنزوانثراسين المحضرة بالطور السائل عند تركيز مولاري ثابت. مديات درجات الحرارة بدات من درجة حرارة الغرفة وصولا الى درجة سائل النتروجين (77كلفن). تم استخدام عدة مذيبات قطبية وغير قطبية لتحضيرمحاليل جزيئة البنزوانثراسين لغرض دراسة تاثير المذيب على اطياف الامتصاص والفلورة لهذه الجزيئة. تم تحديد بعض المعلمات الطيفية من الاطياف المستحصلة كدالة لكل من قطبية المذيب ودرجة الحرارة. اظهرت النتائج ان عرض الحزمة عند منتصف القمة يزداد بزيادة قطبية المذيب ودرجة الحرارة بينما يقل المقطع العرضي لقمة الانبعاث مع زيادة قطبية المذيب ودرجة الحرارة. التركيب الدقيق لاطياف لجزيئات البنزوانثراسين ظهر بوضوح مع مذيب النونان والهيكسان عند 77كلفن.


Article
UV-VIS Absorption Spectral Studies of N, N′-Bis(salicylidene)ethylenediamine (Salen) in Different Solvents

Authors: Khaled Muftah Elsherif1 --- Ahmed Zubi --- Hana Shawish --- Eman Almelah --- et al.
Journal: Iraqi Journal of Science المجلة العراقية للعلوم ISSN: 00672904/23121637 Year: 2019 Volume: 60 Issue: 2 Pages: 204-210
Publisher: Baghdad University جامعة بغداد

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Abstract

In the present study, the influence of various solvents on UV-VIS absorption spectra of N,N-Bis(salicylidene)ethylenediamine (Salen) has been investigated. Salen ligand has two absorption maxima (around 260 and 320 nm). To explain the obtained spectra, the frequencies and molar absorptivity values were combined with solvent properties using a total solvatochromic equation suggested by the Kamlet and Taft. The multiparametric examination denotes that non-specific dipolar interactions of the solvents (π*) with the solute play a significant role in absorption maxima in pure solvents. The ionization constant (pKa) of salen in methanol has been determined by spectrophotometric measurements. Two graphical methods have

Keywords

Schiff base --- Salen --- Solvent Effect --- Copper


Article
Theoretical Study of Solvent Effects on 1,3-Dipolar cycloaddition Reaction

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Abstract

AbstractThe correlation between solvents parameters and rate constant (k) of 1,3-dipolar cycloaddition of benzonitrile oxide and N-ethylmaleimideorcyclopentene(k collected from literature) in different hydroxylic and non hydroxylic solvents were studied. Single parameter correlations were found to be poor(R2< 0.9) except for ϭ* and α; R2=0.903,0.914respectively.Avery good multiparameters correlation was found for the reaction of N-ethylmaleimide(logk=-0.145 +0.719+0.0336 ET(30)+0.844α; R2=0.995.sig:=0.091,F=65.131.While excellentdual parametric correlation was shown when the dipolarophile was cyclopentene (logk=-0.0721,-0.895α-0.0148B ;)R2=0.999, sig: =0.035, F=412.438. Which strongly indicates that protic solvents(HBD solvents) facilitate reactions with HBA dipolarophiles. These results may be useful as priori predictions for these reactions.

الخلاصةان العلاقة بين تاثيرات المذيبات ومعدل ثابت سرعة التفاعل لتفاعلات 1،3 تفاعلات الاضافة الحلقية ثنائية القطبية لمركبات اوكسيد بنزونترايل ومركب ن- اثيل مالياميدورسايكلوبنيتين تم دراستها في الادبيات باستعمال مذيبات مائية وغير مائية. لقد تم ايجاد معامل ارتباط منفرد ضعيف (R2‹0.9 ) لانتقالات ϭ* و α وكذلك تم ايجاد معاملي ارتباط (R2= 0.903 ) وكذلك (R2= 0.914 ) على التوالي.بالنسبة لتفاعل اثيل مالياميد تم ايجاد معامل ارتباط جيد (logk=-0.145 +0.719+0.0336 ET(30)+0.844α) R2=0.995.sig:=0.091,F=65.131).) تم ايجاد معامل ارتباط ثنائي بارامتري ممتاز للمركبات ثنائية القطبية مثل السايكلوبنتين (logk=-0.0721,-0.895α-0.0148B ) (R2=0.999, sig: =0.035, F=412.438). هذه النتائج تدل على ان المذيب الهيدروجيني يسهل التفاعل مع المركبات ثنائية القطبية وهذه العملية تعتبر مفيدة عند توقع احتمالية حصول التفاعل مسبقا.

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