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.
Introduction The Hybrid Gamma Camera (HGC) is being developed to enhance the localisation of radiopharmaceutical uptake in targeted tissues during surgical procedures such as sentinel lymph node (SLN) biopsy. Purpose To assess the capability of the HGC, a lymph-node-contrast (LNC) phantom was constructed for an evaluative study simulating medical scenarios of varying radioactivity concentration and SLN size. Materials and methods The phantom was constructed using two methyl methacrylate PMMA plates (8 mm thick). The SLNs were simulated by drilling circular wells of diameters ranging between 10 mm and 2.5 mm (16 wells in total) in one plate. These simulated SLNs were placed underneath scattering material with thicknesses ranging between 5 mm
... Show MoreReceipt date:2/17/2021 acceptance date:3/16/2021 Publishing date:12/31/2021
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Objective: This paper investigates the contradictions in the decision-making process of the United States, which historically proven to be successful policies in the short term, but in the long term proven to be wanting and failure. Methodology: The paper uses descriptive, historical, comparative method. A
... Show MoreThis study aims to derive a sustainable human development index for the Arab countries by using the principal components analysis, which can help in reducing the number of data in the case of multiple variables. This can be relied upon in the interpretation and tracking sustainable human development in the Arab countries in the view of the multiplicity of sustainable human development indicators and its huge data, beside the heterogeneity of countries in a range of characteristics associated with indicators of sustainable human development such as area, population, and economic activity. The study attempted to use the available data to the selected Arab countries for the recent years. This study concluded that a single inde
... Show MoreThis study aims to characterize traumatic spinal cord injury (TSCI) neurophysiologically using an intramuscular fine-wire electromyography (EMG) electrode pair. EMG data were collected from an agonist-antagonist pair of tail muscles of Macaca fasicularis, pre- and post-lesion, and for a treatment and control group. The EMG signals were decomposed into multi-resolution subsets using wavelet transforms (WT), then the relative power (RP) was calculated for each individual reconstructed EMG sub-band. Linear mixed models were developed to test three hypotheses: (i) asymmetrical volitional activity of left and right side tail muscles (ii) the effect of the experimental TSCI on the frequency content of the EMG signal, (iii) and the effect
... Show MoreThis study is intended to examine the concept of transcultural identity in the travel book The Global Soul: Jet Lag, Shopping Malls, and the Search for Home by (Iyer, 2001). Jeffries’ model of critical stylistics (2010) (henceforth, CS) has been selected to analyze the book. To be more specific, Negation is selected to analyze the concept under study. As such, the study aims at finding out how Negation is used to portray ideological meanings representing the concept of transcultural identity in one non-fictional travel book; and finding out the ideologies related to the concept analyzed. The analysis of the data shows that Negation is a suitable analytical tool to reach the ideational meaning of the text towards the concept of tra
... Show MoreThe corrosion behavior of mild sleet in saturated aerated and de-aerated Ca(OH)2 solution was investigated using electrochemical measurements. The work was carried out with small coupons immersed in solutions containing different quantities of NaCl in presence of various NaN02 concentrations as corrosion inhibitors. It has been found thal:(1 ) In presence of NaCl, the time required to reach O2 evolution potential in de-aerated Ca(OH)2 polarized at 10μA/cm 2 is function of inhibitor concentration and it becomes lass as NaN02 increases compared with zero presence indicating the effectiveness of N
... Show MoreIn this study, a proposed process for the utilization of hydrogen sulphide separated with other gases from omani natural gas for the production of sulphuric acid by wet sulphuric acid process (WSA) was studied. The processwas simulated at an acid gas feed flow of 5000 m3/hr using Aspen ONE- V7.1-HYSYS software. A sensitivity analysis was conducted to determine the optimum conditions for the operation of plant. This included primarily the threepacked bed reactors connected in series for the production of sulphur trioxidewhich represented the bottleneck of the process. The optimum feed temperature and catalyst bed volume for each reactor were estimated and then used in the simulation of the whole process for tw
... Show MoreThe personality characteristics of the Leader are considered one of the main elements to reach into business organizations entrepreneurship; and because of the development of the organizations of the continuous transformations as result of huge Competition in private High Education sector, there is a great need for Leaders characterized of certain personality capable of managing their organizations and can positively effect on them. Also these organizations' success to reach into entrepreneurship requires a main significant element that is (strategic flexibility) which is considered one of the important elements for success.
Accordingly, this research is trying to fin
... Show MoreObjective: to evaluate the increase in weight after biological agents and the association of weight gain with the body mass index among a sample of patients attending Baghdad Teaching Hospital Methods: A prospective study is carried out in Baghdad teaching hospital biological units and outpatient clinic of rheumatology for a period of one year starting On April 2015 and ending on March 2016. 120 patients were included in the study 40 psoriatic arthritis .40 ankylosing spondylitis and 40 rheumatoid arthritis Results : The study findings indicate that significance differences are seen regarding weight gain and b