Promoting the production of industrially important aromatic chloroamines over transition-metal nitrides catalysts has emerged as a prominent theme in catalysis. This contribution provides an insight into the reduction mechanism of p-chloronitrobenzene (p-CNB) to p-chloroaniline (p-CAN) over the γ-Mo2N(111) surface by means of density functional theory calculations. The adsorption energies of various molecularly adsorbed modes of p-CNB were computed. Our findings display that, p-CNB prefers to be adsorbed over two distinct adsorption sites, namely, Mo-hollow face-centered cubic (fcc) and N-hollow hexagonal close-packed (hcp) sites with adsorption energies of −32.1 and −38.5 kcal/mol, respectively. We establish that the activation of nitro group proceeds through direct pathway along with formation of several reaction intermediates. Most of these intermediaries reside in a significant well-depth in reference to the entrance channel. Central to the constructed mechanism is H-transfer steps from fcc and hcp hollow sites to the NO/–NH groups through modest reaction barriers. Our computed rate constant for the conversion of p-CNB correlates very well with the experimental finding (0.018 versus 0.033 s–1 at ∼500 K). Plotted species profiles via a simplified kinetics model confirms the experimentally reported high selectivity toward the formation of p-CAN at relatively low temperatures. It is hoped that thermokinetics parameters and mechanistic pathways provided herein will afford a molecular level understanding for γ-Mo2N-mediated conversion of halogenated nitrobenzenes into their corresponding nitroanilines; a process that entails significant industrial applications.
The extraction of Cupressus sempervirens L. or cypress essential oil was studied in this paper. This cypress oil was extracted by using the hydro-distillation method, using a clevenger apparatus. Cupressus sempervirens L. leaves were collected from Hit city in Al-Anbar province – Iraq. The influences of three important parameters on the process of oil extraction; water which used as a solvent to the solid ratio (5:1 and 14:1 (ml solvent/g plant), temperature (30 to 100 °C) and processing time, were examined to obtain the best processing conditions to achieve the maximum yield of the essential oil. Also, the mathematical model was described to calculate the mass transfer coefficient. Therefore, the best conditions, that were obtained in
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The present study was conducted to estimate the antimicrobial activity and the potential biological control of the killer toxin produced by
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In this work, the possibility of utilizing osmosis phenomenon to produce energy as a type of the renewable energy using Thin Film Composite Ultra Low Pressure membrane TFC-ULP was studied. Where by forward osmosis water passes through the membrane toward the concentrated brine solution, this will lead to raise the head of the high brine solution. This developed static head may be used to produce energy. The aim of the present work is to study the static head developed and the flux on the high brine water solution side when using forward and reverse osmosis membranes for an initial concentration range from 35-300 g/l for each type of membrane used at room temperature and pressure conditions, and finally calculating the maximum possible po
... Show MoreIn this research , Aprocess ( LICVD) was used for producing silicon nitride powders with chemical compositon Si3N4 ,by using TEA-Co2 Laser to induc reaction in the gas phase, NH3 was used as on additive to SiH4. Reactant gases that were vibrationaly heated by absorbing energy emitted from TEA-Co2 Laser decomposes throug coillsion assisted multiple photon dissociation causing Si3N4 powders. By the dependence of the LICVD process on varios parameters such as Laser intensity , total gas pressure, partial pressures of SiH4 and NH3 were investigated. Dissociation rate as a function of Laser intensity and pressure was investigated. The powders obtained exhibit various colors from brown which is rich in Si to white.This
... Show MoreObjectives: In developing countries like Iraq, diarrhea was responsible for 70% of deaths among pediatrics. This study was designed to determine Iraqi mothers’ knowledge and malpractices associated with diarrhea management in pediatrics.Methods: A cross-sectional pilot study was done on a convenient sample of mothers in Baghdad – Iraq. Data collection was done using a validated questionnaire specifically designed for this study.Result: Most participants preferred to consult physicians or pharmacists about pediatrics diarrhea management. Breastfeeding was stopped by 19% of participants, whereas 35% of mothers who depend on formulated milk discontinued it. Only 30% of participants use oral rehydration solution therapy always as a
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Decision making is vital and important activity in field operations research ,engineering ,administration science and economic science with any industrial or service company or organization because the core of management process as well as improve him performance . The research includes decision making process when the objective function is fraction function and solve models fraction programming by using some fraction programming methods and using goal programming method aid programming ( win QSB )and the results explain the effect use the goal programming method in decision making process when the objective function is
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I n this paper ,we 'viii consider the density questions associC;lted with the single hidden layer feed forward model. We proved that a FFNN with one hidden layer can uniformly approximate any continuous function in C(k)(where k is a compact set in R11 ) to any required accuracy.
However, if the set of basis function is dense then the ANN's can has al most one hidden layer. But if the set of basis function non-dense, then we need more hidden layers. Also, we have shown that there exist localized functions and that there is no t
... Show MoreIn this research, a modified artificial hand with direct control has been designed using electrical artificial muscle wires that receive direct sensory impulses through human hand instead of using the mechanical action to open and close this artificial hand. Each finger is designed as a chain and its movements achieved through the conventional arrangement control of the electrical muscles wires. The results indicate that it is possible to design an artificial hand using electrical muscle wire for control it with high accuracy.
Nanocrystalline ZnO/Zeolite type A composite was prepared by simple method of operation by . the precipitation of zinc oxide and loading on zeolite 5A in one step. Characterization was made by X-ray diffraction (XRD), X-ray fluorescence(XRF), N2 adsorption- desorption for BET surface area, and Atomic force microscopy (AFM). Results showed that zinc oxide was loaded on zeolite as noticed by the characteristic peaks and was of nano scale having an average diameter of 88.57nm. The percentage loading of ZnO on zeolite A was 28.37% and the surface area was 222m2/g. The activity of the prepared catalyst was examined in the desulfurization of double hydrogenated diesel fuel. The process was investigated in a
... Show MoreInformation about soil consolidation is essential in geotechnical design. Because of the time and expense involved in performing consolidation tests, equations are required to estimate compression index from soil index properties. Although many empirical equations concerning soil properties have been proposed, such equations may not be appropriate for local situations. The aim of this study is to investigate the consolidation and physical properties of the cohesive soil. Artificial Neural Network (ANN) has been adapted in this investigation to predict the compression index and compression ratio using basic index properties. One hundred and ninety five consolidation results for soils tested at different construction sites
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