Preferred Language
Articles
/
alkej-574
Characterization of Metal Dispersion of Some Naphtha Reforming Catalysts by Methylcyclohexane Dehydrogenation Reaction
...Show More Authors

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

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Dec 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Synthesis and Characterization of Nano Y Zeolite Using MWCNT as Media for Crystal Growth
...Show More Authors

   The present research was conducted to synthesis Y-Zeolite by sol-gel technique using MWCNT (multiwalled carbon nanotubes) as crystallization medium to get a narrow range of particle size distribution with small average size compared with ordinary methods. The phase pattern, chemical structure, particle size, and surface area were detected by XRD, FTIR, BET and AFM, respectively. Results shown that the average size of Zeolite with and without using MWCNT were (92.39) nm and (55.17) nm respectively .Particle size range reduced from (150-55) nm to (130-30) nm. The surface area enhanced to be (558) m2/g with slightly large pore volume (0.231) km3/g was obtained. Meanwhile, degree of crystallization decrease

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Tue Feb 12 2013
Journal Name
International Journal Of Engineering Sciences And Research Technology
Synthesis, Characterization of New Azo Compounds and Studies Effect on the Ach Enzyme(Invitro)
...Show More Authors

Three azo compounds were synthesized in two different methods, and characterized by FT-IR, HNMR andVis) spectra, melting points were determined. The inhibitory effects of prepared compounds on the activity of human serum cholinesterase have been studied in vitro. Different concentrations of study the type of inhibition. The results form line weaver-Burk plot indicated that the inhibitor type was noncompetitive with a range (33.12-78.99%).

Publication Date
Tue May 29 2018
Journal Name
Journal Of Pharmaceutical And Scientific Research
Synthesis and characterization of substituted 1, 2,4-triazole and their derivatives on poly ethylene
...Show More Authors

Abstract New derivatives of 1,2,4- triazole , 1,2,4-triazole -3-one and 1,2,4-triazole-3-thione were obtained through this research. Acid hydrazide derivative was present from reaction of poly acryloyl chloride with hydrazine hydrate in presence of DMF as a solvent then reacted with benzonitrile and its derivatives to give 1,2,4-triazole derivatives. After that reaction of poly acryloyl chloride with semicarbazide and semithiocarbazide to form semicarbazone and semithiocarbazone derivatives respectively. Finally, closing of semicarbazone and semithiocarbazone derivatives with 2% NaOH gave 1,2,4-triazole -3-one and 1,2,4-triazole-4-thione derivatives respectively. These new synthesized products have been characterized by infrared, 1 H-n

... Show More
Publication Date
Sun Oct 01 2023
Journal Name
Journal Of Ovonic Research
Composite nanostructured growth of (CdS)0.75 (PbS)0.25/Si solar cell and its characterization
...Show More Authors

By using vacuum evaporation, thin films of the (CdS)0.75-(PbS)0.25 alloy have been deposited to form a nanocrystalline composite. Investigations were made into the morphology, electrical, optical and I-V characteristics of (CdS)0.75-(PbS)0.25 films asdeposited and after annealing at various temperatures. According to AFM measurements, the values of grain sizes rise as annealing temperatures rise, showing that the films' crystallinity has been increased through heat treatment. In addition, heat treatment results in an increase in surface roughness values, suggesting rougher films that could be employed in more applications. The prepared films have direct energy band gaps, and these band gaps increase with the increase in the degrees

... Show More
View Publication
Scopus Clarivate Crossref
Publication Date
Wed Jun 01 2016
Journal Name
Chalcogenide Letters
Characterization, morphology and electrical properties of chemically deposited nanocrystalline PbS/Si heterojunction thin films
...Show More Authors

A nanocrystalline thin films of PbS with different thickness (400, 600)nm have been prepared successfully by chemical bath deposition technique on glass and Si substrates. The structure and morphology of these films were studied by X-ray diffraction and atomic force microscope. It shows that the structure is polycrystalline and the average crystallite size has been measured. The electrical properties of these films have been studied, it was observed that D.C conductivity at room temperature increases with the increase of thickness, From Hall measurements the conductivity for all samples of PbS films is p-type. Carrier's concentration, mobility and drift velocity increases with increasing of thickness. Also p-PbS/n-Si heterojunction has been

... Show More
Publication Date
Fri Aug 25 2023
Journal Name
Journal Of Composites Science
Powder Metallurgy Preparation and Characterization of Titanium-Titanium Diboride Composite Targeted for Dental Implant
...Show More Authors

Due to the advantages over other metallic materials, such as superior corrosion resistance, excellent biocompatibility, and favorable mechanical properties, titanium, its alloys and related composites, are frequently utilized in biomedical applications, particularly in orthopedics and dentistry. This work focuses on developing novel titanium-titanium diboride (TiB2; ceramic material) composites for dental implants where TiB2 additions were estimated to be 9 wt.%. In a steel mold, Ti-TiB2 composites were fabricated using a powder metallurgy technique and sintered for five hours at 1200 °C. Microstructural and chemical properties were analyzed by energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ra

... Show More
View Publication
Scopus (3)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Fri Feb 09 2001
Journal Name
Molecular Crystals And Liquid Crysta
Synthesis and characterization of symmetrical liquid crystalline compounds based on oxazole and thaizole rings
...Show More Authors

Twelve compounds containing a sulphur- or oxygen-based heterocyclic core, 1,3- oxazole or 1,3-thiazole ring with hydroxy, methoxy and methyl terminal substituent, were synthesized and characterized. The molecular structures of these compounds were performed by elemental analysis and different spectroscopic tequniques. The liquid crystalline behaviors were studied by using hot-stage optical polarizing microscopy and differential scanning calorimetry. All compounds of 1,4- disubstituted benzene core with oxazole ring display liquid crystalline smectic A (SmA) mesophase. The compounds of 1,3- and 1,4-disubstituted benzene core with thiazole ring exhibit exclusively enantiotropic nematic liquid crystal phases.

Scopus (9)
Scopus
Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Synthesis and Characterization of New Mannich Bases Derived from 7-hydroxy-4-methyl Coumarin
...Show More Authors

Coumarin is a natural substance isolated from different plants. It belonges to a group of benzobyrones which consists of a benzene ring joined to a pyrone nucleus. In the present research, a new series of coumarin derivatives were formed. Compound (1) (7-hydroxy-4-methyl Coumarin) was converted into 4-methylquinolin-2(H) derivative (2) by reaction with acetamide, and then reaction of (2) with thiosemicarbazide in ethanol leads to the synthesize of hydrazincarbothioamide derivative (3).The reaction of (3) with ethylchloroacetate in presence of sodium acetate leads to closure ring to get [(1-(5-oxo-2-thioxoimidazolidin-1-ylimino) ethyl)]quinolin-2(1H)-one (4). Mannich bases were prepared through the reaction of (4) with primary

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Jul 03 2013
Journal Name
Eur. Chem. Bull
PREPARATION AND CHARACTERIZATION OF UNSATURATED POLYESTER MATERIAL BLENDED WITH CELLULOSE AND WITH ETHYL CELLULOSE.
...Show More Authors

Modified unsaturated polyester (MUPE) was blended with Cellulose (Cls) and with ethyl cellulose (ECls) at ambient conditions in the presence of ethyl methyl ketone peroxide (EMKP) as hardener. The blends containing different weight percentages (5-25 %) of Cls or ECls. Mechanical properties (impact strength, hardness, and bending) and dielectric constant were determined. The results observed that Cls increases the impact strength, hardness, and dielectric constant and decreases the bending of the MUPS, while ECls causes an increase in the three mechanical behaviours and a decrease in the dielectric constant of the MU-PS.

Publication Date
Tue Mar 28 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Design, Synthesis, Characterization and Comparative Cytotoxic Evaluation of bis-(2- mercaptoacetate) gold (III) chloride
...Show More Authors

In recent years , the interest in gold (III) species have gained more and more attention for cancer chemotherapy , this was stimulating by the possibility to develop new agents with mode of action and clinical profile different from the established platinum metalodrugs.

With this frame, recently new square planar Au(III)  complexes (Au(L)(L')n); where L=SCH2COO- ; L'=HSCH2COO- had been synthesized with S/O – donor ligands.

In this article and by the aim to replace, one of (L') ligand by anion chloride ligand (which supposedly more relevant for the biodistribution of the compound than for its pharmacodynamic effects), new complex (Au(L')

... Show More
View Publication Preview PDF
Crossref