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Characterization of Metal Dispersion of Some Naphtha Reforming Catalysts by Methylcyclohexane Dehydrogenation Reaction
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The dispersion of supported Pt and Pt–Ir reforming catalysts have been studied, after treatment with oxidative and reducing atmosphere. Methylcyclohexane dehydrogenation reaction in the absence of hydrogen was used as a test reaction. An attempt was made to relate the behavior of the catalysts upon subject to reaction, to the dispersion of the same type of catalysts upon treatment with similar atmosphere and temperatures which appeared in literature. The total conversion of reaction can be explained by a change in metal dispersion. Thus, methylcyclohexane dehydrogenation reaction appears to be a really “structure sensitive” reaction.

      The toluene yield increases as the oxidation temperature increases over the studied catalyst RG-402, RG-412, RG-422 and RG-432 respectively and reached a maximum value at 550°C. Above 550 the conversion decreases due to the effect of catalyst sintering.

      No significant change were observed for reduction temperature range 400-600°C for the above studied catalysts.

      The selectivity order for the studied catalysts and for reduction treatment experiments arranged as

follows:

RG-422> RG-432> RG-412> RG-402

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Publication Date
Fri Aug 30 2024
Journal Name
مجلة كلية اللغة العربية بأسيوط
Shades of meanings of letters in Arabic (Some double and triple letters are an example)
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Meaning letters in Arabic are characterized by the diversity and abundance of their linguistic material, and are also distinguished by their large number and types, to the point that some of them have reached a hundred letters confined to five categories

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Publication Date
Tue Jun 21 2022
Journal Name
Journal Of Planner And Development
Evaluation of some indicators of urbanization in the city of al-Qaim in the Iraqi province of Anbar
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Urban Balance is one of the important indicators that leads to an assessment of the urbanization process in a particular country  , province or even a city that is multi-centered. By examining  the data related to Anba  province, it was found that the value of this indicator is equal to 0.96, which is less than the absolute one, and therefore the urbanization in the province is distributed collectively  

The development of a mathematical or statistical model for estimating urban growth is a complex process due to the overlap between indicators or variables that can be adopted to calculate estimate growth rates Al-Qaim city has been considered as an example to develop a statistical method by which changes

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Publication Date
Wed Dec 31 2014
Journal Name
Al-khwarizmi Engineering Journal
Energy Saving of Heat Gain by Using Buried Pipe Inside a Roof
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Abstract

    This work deals with a numerical investigation to evaluate the utilization of a water pipe buried inside a roof to reduce the heat gain and minimize the transmission of heat energy inside the conditioning space in summer season.     The numerical results of this paper showed that the reduction in heat gain and energy saving could be occurred with specific values of parameters, like the number of pipes per square meter, the ratio of pipe diameter to the roof thickness, and the pipe inlet water temperature. Comparing with a normal roof (without pipes), the results indicated a significant reduction in energy heat gain which is about 37.8% when the number of pipes per m

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
Some Methodological Notes on Ibn Al-Jezri Book: Ghayat Al-Nihaya (The Aim of the End): Some Methodological Notes on Ibn Al-Jezri Book: Ghayat Al-Nihaya (The Aim of the End)
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Abstract
Dame Ngaio Edith Marsh (1899-1982), a writer of detective fiction, was born
at Christchurch, New Zealand. Her hero, Chief Detective Inspector Roderick Alleyn,
appears in her first novel, A Man Lay Dead (1934), and in subsequent novels
including Death and the Dancing Footman (1942). She wrote twenty detective novels.
The Dancing Footman, Thomas, listening to a playful song from the smokingroom's
radio where William lay dead after being killed by his brother, Nicholas,
provides the most suspected guest at Highfold with badly needed alibi. The murderer,
Nicholas, plans an almost perfect crime, but the dance of this footman spoils his
scheme. When Alleyn and his group of policemen stage a show in which the

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Publication Date
Tue Oct 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of some robust methods in the presence of problems of multicollinearity and high leverage points
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Abstract

The multiple linear regression model of the important regression models used in the analysis for different fields of science Such as business, economics, medicine and social sciences high in data has undesirable effects on analysis results . The multicollinearity is a major problem in multiple linear regression. In its simplest state, it leads to the departure of the model parameter that is capable of its scientific properties, Also there is an important problem in regression analysis is the presence of high leverage points in the data have undesirable effects on the results of the analysis , In this research , we present some of

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Publication Date
Tue Mar 28 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Preparation, Characterization, and in - vivo Evaluation of Daptomycin Poly(D,L-lactide-co-glycolide) Microspheres
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             Polymeric microsphere devices occupy a wide range in the field of controlled drug delivery. Subcutaneous injectable preparations of Poly(Lactide-co-Glycolide) (PLGA) microsphere of Daptomycine were prepared by solvent extraction/evaporation technique using different copolymers ratio and molecular weights. Four formulations were prepared (F1-F4) and characterized in term of particle size, surface morphology, bulk density and porosity in addition to the drug content. The effects of the above parameters on the in-vitro release study were evaluated. These formulas were evaluated also for their in-vivo release profile using rat (as an animal model) and

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Publication Date
Sun Apr 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis And Characterization of 5-(Mercapto-1,3,4Thiadiazole-2yl)α,α-Diphenyl Methanol From Benzilic Acid
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  5-(mercapto-1,3,4-thiadiazole-2yl)α,α-(diphenyl)methanol have been synthesized by ring closer of potassium xanthate[which  have been prepared by reaction of benzilic acid hydrazide with carbon disulphide in potassium hydroxide] using conc.sulphuric acid at (0-5)°C scheme(I).       Their characterization was carried out from T.L.C, M.P, FT.IR and 1H-NMR.

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Publication Date
Mon May 22 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis , Characterization and Study The Liquid Crystalline Properties of N-Acyl , Thiourea and Imidazole Derivatrives.
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    The synthesis , characterization and mesomorphic behaviour of new Nacyl , thiourea and imidazole derivatives which derived from corresponding Schiff bases are reported.             All the synthesized compounds which contain flexible methylene group in the centre of the molecule did not show any liquid crystalline properties . The derivatives of N- acyl [III]e  and thiourea [VI]e  which contain  biphenyl and all compounds with one phenyl in the centre of the molecule display liquid crystalline behaviour .While the imidazoles did not show any liquid crystalline properties except [V]b [V]e  with biphenyl in the centre of the molecule . All th

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Publication Date
Fri Jul 01 2016
Journal Name
Tetrahedron
Novel bent-core mesogenic of 4-amino-triazole derivatives: synthesis, characterization and liquid crystalline study
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Publication Date
Sun Nov 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Fatigue Characterization for Composite Materials used in Artificial Socket Prostheses with the Adding of Nanoparticles
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Abstract<p>The prostheses sockets use normally composite materials which means that their applications may be related with the human body. Therefore, it was very necessary to improve the mechanical properties of these materials. The prosthetic sockets are subjected to varying stresses in gait cycle scenario which may cause a fatigue damage. Therefore, it is necessary or this work to modify the fatigue behavior of the materials used for manufacturing the prostheses sockets. In this work, different Nano particle materials are used to modify the mechanical properties of the composite materials, and increase the fatigue strength. By using an experimental technique, the effect of using different volu</p> ... Show More
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