Motivated by the vital role played by transition metal nitride (TMN) composites in various industrial applications, the current study reports electronic properties, thermodynamic stability phase diagram, and vacancy formation energies of the plausible surfaces of NiAs and WC-type structures of δ3-MoN and δ-WN hexagonal phases, respectively. Low miller indices of various surface terminations of δ3-MoN and δ-WN namely, (100), (110), (111), and (001) have been considered. Initial cleaving of δ3-MoN bulk unit cell offers separate Mo and N terminations signified as δ3-MoN (100): Mo, δ3-MoN(100):N, δ3-MoN(111):Mo, δ3-MoN(111):Mo, and δ3-MoN(001):Mo. However, the (110) plane reveals mix-truncated with both molybdenum and nitrogen atoms i.e. δ3-MoN (110): MoN. Likewise, the δ-WN faces incur analogous surface terminations. Ab initio atomistic thermodynamic analyses predict that, N-terminated (111) and (100) slabs to be the most energetically favourable surface terminations amongst the explored surfaces of δ3-MoN and δ-WN, respectively. Evidenced by plotted density of states (DOS), bulk and surfaces of δ3-MoN and δ-WN display a metallic character. In terms of surface relaxation and reconstructions, most investigated surfaces experience mainly downward displacements of their topmost layers. Most notably, the relaxed Mo-termination in (111) and (100) surfaces of δ3-MoN demonstrate significant reconstructions resulted in the first layer to be solely truncated with nitrogen atoms instead of molybdenum in the un-relaxed geometry. Nevertheless, no surface reconstruction has been noticed in most of considered δ-WN configurations. Calculated Bader's electronic charges reveal charge transfer from Mo/W atoms to N atoms, largely retaining the ionic bond nature in their bulk phases. Finally, vacancy formation energy (VFE) calculations showed that introducing nitrogen vacancies through the surface is an endothermic process. Furthermore, the energy required to create a vacant cite in the inner layers differ than that needed in the outer layers. Nitrogen-terminated slabs hold the highest concentrations. Results from this study should be useful when studying the activation of doubly and triply bonded molecules such as N2 at surface vacancies.
In this work a novel drug delivery system through modification of poly acrylic acid with Methionine as a spacer between the poly acrylic acid which was converted to its acyl chloride and reacted with Methionine as spacer unit which has been reacted with Ampicillin drug. In vitro drug release study had been conducted successfully in basic medium in pH 7.4 and acidic medium in pH 1.1 at 37?. Due to many problems associated with drug release and, this modification could decrease the side effect of drug. The prepared prodrug polymer was characterized by spectra method [FTIR and 1H?NMR]. Physical properties and intrinsic viscosity of drug polymer were determined. The good results were obtained in the presence of spacer unit with compar
... Show MoreAfter receipt of military commanders power in 1980, they were determined to solve the
Kurdish question by force, just like their predecessors in resolving such issues, and the
situation became worse when the Kurdish resistance in a more organized than previous years
and behind the Party (PKK) .
After the mass support of the Kurdish widespread party get involved most of the Kurdish
youth in the party organization of the (PKK), prompting Turkish President then to make
decisions and take immediate action firm against the party, but the Kurdish issue began
Tthlhal when he arrived at the helm of President Turgut Ozal in 1989, he worked on the
development of the areas inhabited by the Kurds, specifically the Southeast A
Since the property in Islam is based on the principle of succession , "which made you Khalaúv land and raise yourselves above some degree of Iblukm with Atakm The Lord of the fast punishment and it is Forgiving, Merciful " [cattle : 165 ] and human only Mstkhalaf where " God promised you who believe and do good deeds for Istkhalvenhm Normans in the ground as those before them " [Nur : 55 ] , considering that King God alone any talk about having ownership in Islam in the contemporary sense of ownership , containing three rights are:
1- right to dispose of the right of usufruct tenure
2-The concept is ambiguous as long as that man Mstkhalaf does not have the right to dispose
... Show MoreChaotic systems have been proved to be useful and effective for cryptography. Through this work, a new Feistel cipher depend upon chaos systems and Feistel network structure with dynamic secret key size according to the message size have been proposed. Compared with the classical traditional ciphers like Feistel-based structure ciphers, Data Encryption Standards (DES), is the common example of Feistel-based ciphers, the process of confusion and diffusion, will contains the dynamical permutation choice boxes, dynamical substitution choice boxes, which will be generated once and hence, considered static,
While using chaotic maps, in the suggested system, called
This study delves into the properties of the associated act V over the monoid S of sinshT. It examines the relationship between faithful, finitely generated, and separated acts, as well as their connections to one-to-one and onto operators. Additionally, the correlation between acts over a monoid and modules over a ring is explored. Specifically, it is established that functions as an act over S if and only if functions as module, where T represents a nilpotent operator. Furthermore, it is proved that when T is onto operator and is finitely generated, is guaranteed to be finite-dimensional. Prove that for any bounded operator the following, is acting over S if and only if is a module where T is a nilpotent operator, is a
... Show MoreKE Sharquie, AA Noaimi, AH Muhammad Ali, 2008 - Cited by 3
This work is concerned with the design and performance evaluation of a shell and double concentric tubes heat exchanger using Solid Works and ANSY (Computational Fluid Dynamics).
Computational fluid dynamics technique which is a computer-based analysis is used to simulate the heat exchanger involving fluid flow, heat transfer. CFD resolve the entire heat exchanger in discrete elements to find: (1) the temperature gradients, (2) pressure distribution, and (3) velocity vectors. The RNG k-ε model of turbulence is used to determining the accurate results from CFD.
The heat exchanger design for this work consisted of a shell and eight double concentric tubes. The number of inlets are three and that of o
... Show MoreThis article aims to estimate the partially linear model by using two methods, which are the Wavelet and Kernel Smoothers. Simulation experiments are used to study the small sample behavior depending on different functions, sample sizes, and variances. Results explained that the wavelet smoother is the best depending on the mean average squares error criterion for all cases that used.
The objective of this study was to investigate the levels of depression, anxiety, and stress among dentists during covid-19 lockdown and to investigate the relationship between stress and each mental health state.
A cross-sectional survey on 269 dentists was conducted using DASS-21 and PHQ-9 questionnaires. Bivariate and multivariate models were constructed and the odds ratio (OR) was calculated to assess the strength of the association between an independent categorical variable and the outcome.
Being unsatisfied with the job was as