Increasing demands on producing environmentally friendly products are becoming a driving force for designing highly active catalysts. Thus, surfaces that efficiently catalyse the nitrogen reduction reactions are greatly sought in moderating air-pollutant emissions. This contribution aims to computationally investigate the hydrodenitrogenation (HDN) networks of pyridine over the γ-Mo2N(111) surface using a density functional theory (DFT) approach. Various adsorption configurations have been considered for the molecularly adsorbed pyridine. Findings indicate that pyridine can be adsorbed via side-on and end-on modes in six geometries in which one adsorption site is revealed to have the lowest adsorption energy (–45.3 kcal/mol). Over a nitrogen hollow site adsorption site, initial HDN steps proceed by the stepwise hydrogenation of pyridine into piperidine followed by the Langmuir–Hinshelwood mechanism. The obtained findings are the first to theoretically model the hydrogenation pathways of pyridine to form piperidine and then the hydrogenolysis of piperidine producing C5H12 and NH3 over metal nitride. These paved the way for further investigations to better understanding such an important nitrogen removal reactions.
شهد العالم مع بداية القرن الحادي والعشرين تدشين مرحلة جديدة من التطور شملت مختلف الميادين لاسيما في مجال التطورات العلمية والثورة المعلوماتية.. كما إن مسار الديمقراطية في بعض دول العالم يصبح سالكا خاصة في تركيا, فمنذ اواسط الثمانينيات من القرن الماضي فتح المجال السياسي امام قوى كانت مسحوقة ومهمشة, ويكاد ان لا يكون لها وجود في الحياة السياسية للنزول الى ساحة العمل السياسي اسوة ببقية القوى ا
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The wall of the esophagus in Mabuya aurata septemaeniata as in high vertebrates consists of four layers, mucosa, submucosa,muscularis and serosa. Mucosa forms many unorganized short and long folds penetrate inside the esophageal cavity. Mucosa contains two sub layers, first one is lining epithelium which includes two types of cells, simple ciliated columnar epithelial cells and goblet cells, second one is lamina properia. Mucosa does not have muscularis mucosa. There is no esophageal glands within esophagus. Many special stains were used as (Periodic Acid Schiff (PAS)) to detect Carbohydrates in goblet cells. Alcian blue were used to detect the amount of goblet cells within lining epithelium. Alcian blue + PAS together confirm that the
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the sera levels of luteninizing hormone were investgaited prior tq surgery in 10 postmenopaisal women with benign and 10 postmenopausal women with maliganant healthy
Simple and sensitive spectrophotometric method is described based on the coupling reaction of tetracycline hydrochloride (TC. HCl) with diazotized 4-aminopyridine in bulk and pharmaceutical forms. Colored azo dye formed during this reaction is measured at 433 nm as a function of time. Factors affecting the reaction yield were studied and the conditions were optimized. The kinetic study involves initial rate and fixed time (10 minutes) procedures for constructing the calibration graphs to determine the concentration of (TC. HCl). The graphs were linear for both methods in concentration range of 10.0 to 100.0 μg.mL-1. The recommended procedure was applied successfully in the determination of (TC. HCl) in its commercial formulations.
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The aim of this stud to isolate and identified of A. fumigatus from different sources and study the genetic diversity among these isolates by using RAPD and ISSR markers.Collected 20 samples from 7samples were isolated A. fumigatusisolates were characterized depending on its morphological, then extracted DNA from its.RAPD markersrandomly bandingwith sitesof genome more than ISSR markers where the primer OPN-07 achieved discriminative power (19.1) and 43 bands, while ISSR6 achieved discriminative power (17.1) with 32 bands.ISSR were more efficiency in specific binding then RAPD, ISSR primers has great a binding to production unique band, when 9 primers from 01 primers, ISSR9 was produce (5) unique bands, while RAPD markers was low ability
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The objective of this study was to isolate and identify the asparaginase-producing bacteria, then purify and characterize the enzyme in order to investigate their properties in the future. Fifteen local bacterial isolates were isolated from various sites in the city of Baghdad, identified by conventional morphological and biochemical procedures, and confirmed using vitek 2 methods, and submitted to primary screening processes for asparaginase production. For secondary screening, eight isolates with the greatest yellow zone ability on a specific solid medium were chosen. Bacillus sp. was reported to have the highest enzyme production (7.5 U/mg proteins). After 24 hours of incubation, submerged fermentation yielded optimal conditi
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Poly(L-lactic acid) (PLLA)/poly(caprolactone) (PCL) and two types of organoclay (OMMT) including a fatty amide and ocatdecylamine montmorillonite (FA-MMT and ODA-MMT) were employed to produce polymer nanocomposites by melt blending. Materials were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), elemental analysis, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Mechanical properties were also investigated for these nanocomposites. The nanocomposites showed increasing mechanical properties and thermal stability. XRD results indicated that the materials formed nanocomposites. SEM morphology showed that increasing content of OMMT reduc
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The current research dealt with the development of sciences and arts over the course of human history, and the development of sciences with their natural and human trends are important areas in developing the knowledge and application base for industrial product design and design in its various fields. Bionic science is one of the sciences that works on applying biological methods and systems found in nature to study and design engineering systems and modern technology, and for industrial products to be highly efficient, durable and resistant to natural variables in daily life for use. The transfer of technology between life forms and industrial products is desirable because the processes of development at the level of science in general
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