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Study of Catalysts Deactivation in Isomerization Process to Produce High Octane Gasoline
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In this study  the isomerization of desulfuerized light Iraqi petroleum naphtha (Al-Dura Refinery) with boiling point range of 37 to 124 °C , 80.5 API specific gravity and 68.2 octane number has been investigated. Two types of catalysts were prepared (Pt/HX and Pt/SrX) by impregnation of 0.8 wt% Pt on l 3X-zeolite. The catalyst activity and selectivity toward isomerization, and catalyst deactivation were investigated.

The isomerization unit consisted of a vertical tubular stainless steel reactor of 2 cm internal diameter, 3 cm external diameter and 68 cm height. The operating pressure was atmospheric for all experimental runs.  The liquid flow of light­naphtha was 0.4 Uh, and the catalyst weight was 50 gm, H/ H.C ratio used was 4 for all experimental runs. The isomerization process was studied at different temperatures of 250, 270, 275, 300, 325, and 350 °C . It was found that, the optimum isomerization temperature is 270 °C.

The isomerization activities and selectivities as a function of time showed high activity at the beginning of the reaction and were deactivated rapidly. This indicates that the deactivation of Pt/HX and Pt/SrX results from the blocking of pore mouth by the deposited carbon. The following deactivation decreasing order, Pt/HX > Pt/SrX was found. On the other hand, Pt/HX catalyst shows higher activity and selectivity than that of Pt/SrX

It was concluded that, only an average o/ 90 wt% of the carbon atoms feed  into the reactor (light naphtha) is detected " the product stream due to formation of coke deposits which leads to catalyst deactivation. The results clearly showed 1at hydrogen is necessary for the hydrogenation of olefins in order to prevent oligomerization reaction that leads to coke formation and catalyst deactivation.

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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
The House of Illusions A Study in Genet's The Balcony
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The definition of "prostitute" and prostitution is a difficult one and a
question over which the legislators of many lands and nations differed. A
notable feature of prostitution is its epidemic increase at times of war,
revolution and armed commotion, on account of economic, social and
psychological factors generated by such conditions of mortal conflicts. Wars
invariably deprive young wives and lovers of their men folk, resulting in
financial , sexual and emotional frustrations . At no time is the natural
balance between the sexes more seriously disturbed than during wars, when
thousands of men are thrown into one sector of the country and hundreds of
towns and villages are left to women and children only. Lo

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Publication Date
Fri Jun 15 2018
Journal Name
Journal Of Baghdad College Of Dentistry
Bacterial Contamination of Acrylic Resin Complete Denture : In Vitro Study
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Background: Cross contamination of dental appliances in the dental clinics and laboratories may potentially be a health hazard to the dental team and the patient. This study aimed to evaluate bacterial contamination of acrylic complete denture as received from dental laboratory before delivery to the patient, and then to evaluate the effectiveness of disinfection with 2% chlorhexidine and Kin denture cleaner tablet. Materials and methods: 45 newly made upper complete dentures undergone biaacterial examination for contamination before delivered to the patient. Samples were examined in two stages, first after finishing and polishing; when collected from the laboratory and before inserting to the patient mouth, second; after the samples were

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Publication Date
Sun Nov 07 2021
Journal Name
Iraqi Journal Of Embryos And Infertility Researches
Histochemical Study of Human Placental Tissues in Gestational Diabetic Mellitus
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Gestational Diabetes Mellitus (GDM) is the most common metabolic disorder that found during gestation and is define as hyperglycemia of variable severity with onset or first recognition during gestation that does not clearly characterize any form of the preexisting diabetes (American Diabetes Association [1]). It affects approximately 16.5% of pregnancies worldwide (Plows, et al.[2]). The placenta is an organ that connects the mother and her fetus during pregnancy (Gul, et al.[3]). In the placenta, glucose can be transformed into glycogen for storage by either glycogen synthase or using glycogenin as a prime. However, the function of glycogen deposition stays a matter of debate, it may be the source of fuel for placenta itself or the storag

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Publication Date
Thu Apr 27 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Taxonomical Study of The Genus Oxalis L. (Oxalidaceae) in Iraq
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   The current study included collection for many fresh specimens, the observation of specimens in some Iraqi herbaria have been studied, although morphological characters of roots, stems, flowers, inflorescences and fruits were included in this work, however indumentums  and pollen grains were studied

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Publication Date
Thu Mar 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Administrative competencies in many of Iraqi public Organizations: comparative study.
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Competencies topic in general , and Administrative competencies in specific, are considered as important subject in the contemporary administrative literature in all countries as well as in public and privet Organizations. For this reason, we have need to study those competencies in many Iraqi Organizations.

Two Organizations wer chosen for this research one of them is the Institution of taxation, and the other is the General company of Electric the data and information related to the research have been collected by desined questioner which has been given to a sample of (50) persions divided eqully between the two maintioned organizations.

The results of the study had differences

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Publication Date
Sun Apr 02 2017
Journal Name
Journal Of Educational And Psychological Researches
Assisting Students of Al-Quds Open University to Design Computerized Lessons According to ADDIE
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This Action research aimed at Assisting Students of Faculty of Educational Sciences  at Al-Quds Open University to design computerized  lessons using the Power Point software and according to ADDIE model. The study sample consisted of 40 students  who were taking a course titled Technology of Education during the second semester of the 2014-2015 academic year and three academic instructors . To collect the required date  , the researchers used  focus group technique and structured interviews to get information from the 40 students and the three academic instructors involved in the course Technology of Education in QOU /Nablus Branch. In addition to these methods, a workshop with a guiding checklist was employed t

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Publication Date
Wed Mar 01 2023
Journal Name
Accounting And Financial Sciences Journal
The Extent to which the Quality of Accounting Information Systems Contributes to Reducing Material
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This research dealt with shedding light on the nature of material misrepresentations, in addition to knowing the extent to which the quality of accounting information systems contributes to reducing material misrepresentations On the theoretical side, a number of sources were relied upon in dealing with the research problem and presentation of the topic, while in the practical side, it was relied on the questionnaire form, where the research sample was (accountants and auditors), where 50 forms were distributed and 50 were received, and the data was analyzed and hypotheses tested through the program Statistical spss to show the relationship between the variables. The research reached a number of conclusions, the most important of which is t

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Publication Date
Wed Aug 16 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Mass Spectrometric Determination OF Radioactive Decay OF 87Rb TO 87Sr IN Some Iraqi Geological Minerals
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Determination of isotopic composition of strontium and Rubidium in some geological samples was performed by using thermal ionization mass spectrometry. The optimum evaporation and ionization currents were determined for each of strontium and Rubidium, employing double rhenium filament by using faraday cup as detector. The results were compared  with  reference  mater ials (NBS Standards) of Sr and Rb. The

radioactive decay of 87Rb to 87Sr was also determined.

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Publication Date
Wed Mar 16 2022
Journal Name
Journal Of Educational And Psychological Researches
Learning Cleverness of Physics Teachers in Secondary Stages According To the Variable Years of Service
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This current research aims to reveal the difference between the levels of teaching expertise of physics teachers according to the years of service by answering the following question: does the educational skill level of physics teachers work according to the service? The sample of the study consisted of (225) physics teachers by (125) females (56%), and (100) males (44%), distributed on (4) education directorates in Baghdad governorate on both sides of al-Karkh and al-Rusafa. In order to achieve the aim of the study, the researcher prepared a note card for expertise teaching, consisting of (39) paragraphs distributed into (5) fields. The apparent validity and reliability of the card were verified through an agreement (the researcher hers

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Publication Date
Fri Mar 19 2021
Journal Name
Plant Archives 21 (1), 1463-1469‏
Effect of addition of organic fertilizer and rootstock in Lemon transplants exposed to water stress‏
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