The effect of hydrogen on the magnetic properties of FeV superlattice

The electronic and magnetic structures of a hydrogenated and hydrogen free superlattice of 3 iron monolayers and 9 vanadium monolayers are studied using the first principle full-potential augmented-plane-wave method as implemented in WIEN2k package. The volume, the total energy and the magnetic moments of the system are studied versus the hydrogen positions at the octahedral sites within the superlattice and also versus the filling of the vanadium octahedral location by hydrogen atoms. It is found that the hydrogen locations at the interior of vanadium layer are energetically more favourable. The local Fe magnetic moment and the average magnetic moment per supercell are found to increase as the H position moves towards the Fe-V interface. On the other hand, the average magnetic moment per supercell is found to initially decrease up to filling by 3 H atoms and then increases afterwards. To our knowledge, this is the first reporting on the increase in the computed magnetic moment with hydrogenation. These trends of magnetic moments are attributed to the volume changes resulting from hydrogenation and not to electronic hydrogen-metal interaction.Comment: 13 pages, 5 figures and 2 table

Evaluation of serological test in the diagnosis of Helicobacter pylori and risk factors associated with the infection

Background: Serological testing has been widely used for the diagnosis of H. pylori. This study aimed to evaluate the serological test and to determine the sensitivity and specificity of the test in the diagnosis of H. pylori. The study also aimed to address if there are risk factors like blood grouping, Smoking, Age, gender, and residence of the patients associated with H. pylori infection.Methods: A prospective cross‑sectional study was performed among 100 symptomatic patients attending Dr. Suliman dispensary, Elnehoud city in west Kordofan state-Sudan, from March to September 2016. H. pylori were detected on plasma by using Healgen immunochromatography test cards from Xiamen Boson Biotech Co., Ltd (China), and identified from a stool by using monoclonal antigen detection from the same trademarked company. Data for the risk factors associated with the infection were assessed in a participant interview.Results: The serological test showed significant differences when compared to the stool antigen test p-value = 0.000. The statistical analysis showed moderate sensitivity and high specificity of the serological test compared to the stool antigen detection test. The study also showed that smoking [odds ratio (OR): 1.20, 95% confidence interval (CI): (1.24-4.02) and blood grouping (OR: 1.10, 95% CI: (1.08-1.60) were risk factors for H. pylori infection.Conclusions: The serological test showed high specificity and moderate sensitivity in comparison to the stool antigen test. The increased risk of H. pylori infection associated with smoking and blood grouping

Partial distance-learning training for information technology higher education trainers

Teachers must be able to adapt to a rapidly changing IT knowledge and technology. This requirement is further compounded by the need that this knowledge and technology be incorporated in the curriculum at the same rate. This paper presents a strategic approach for updating curriculum and technical know-how of information technology through training the IT trainers. This approach is expected to help modernize the IT training in the developing country by educating the youth who are at the receiving end of this training. In order to ensure the economic feasibility of this approach, teaching methods conducted were based on a combination of traditional methods and modern distance learning techniques.Education for the 21 st century - impact of ICT and Digital Resources ConferenceRed de Universidades con Carreras en Informática (RedUNCI

Partial distance-learning training for information technology higher education trainers

Teachers must be able to adapt to a rapidly changing IT knowledge and technology. This requirement is further compounded by the need that this knowledge and technology be incorporated in the curriculum at the same rate. This paper presents a strategic approach for updating curriculum and technical know-how of information technology through training the IT trainers. This approach is expected to help modernize the IT training in the developing country by educating the youth who are at the receiving end of this training. In order to ensure the economic feasibility of this approach, teaching methods conducted were based on a combination of traditional methods and modern distance learning techniques.Education for the 21 st century - impact of ICT and Digital Resources ConferenceRed de Universidades con Carreras en Informática (RedUNCI

Partial distance-learning training for information technology higher education trainers

Teachers must be able to adapt to a rapidly changing IT knowledge and technology. This requirement is further compounded by the need that this knowledge and technology be incorporated in the curriculum at the same rate. This paper presents a strategic approach for updating curriculum and technical know-how of information technology through training the IT trainers. This approach is expected to help modernize the IT training in the developing country by educating the youth who are at the receiving end of this training. In order to ensure the economic feasibility of this approach, teaching methods conducted were based on a combination of traditional methods and modern distance learning techniques.Education for the 21 st century - impact of ICT and Digital Resources ConferenceRed de Universidades con Carreras en Informática (RedUNCI

Analytical solutions of the space–time fractional Kadomtsev–Petviashvili equation using the (G’/G)-expansion method

This paper focusses on the nonlinear fractional Kadomtsev–Petviashvili (FKP) equation in space–time, employing the conformable fractional derivative (CFD) approach. The main objective of this paper is to examine the application of the (G’/G)-expansion method in order to find analytical solutions to the FKP equation. The (G’/G)-expansion method is a powerful tool for constructing traveling wave solutions of nonlinear evolution equations. However, its application to the FKP equation remains relatively unexplored. By employing traveling wave transformation, the FKP equation was transformed into an ordinary differential equation (ODE) to acquire exact wave solutions. A range of exact analytical solutions for the FKP equation is obtained. Graphical illustrations are included to elucidate the physical characteristics of the acquired solutions. To demonstrate the impact of the fractional operator on results, the acquired solutions are exhibited for different values of the fractional order α, with a comparison to their corresponding exact solutions when taking the conventional scenario where α equals 1. The results indicate that the (G’/G)-expansion method serves as an efficient method and dependable in solving the nonlinear FKP equation

First principle calculation of the electronic and magnetic properties of Mn-doped 6H-SiC

The electronic and magnetic properties of 6H-SiC with Mn impurities have been calculated using GGA formalism. Various configurations of Mn sites were considered. It was found that 6H-SiC doped with Mn atoms possess a moment for both types of substitution. The Mn atom at Si site possesses larger magnetic moment than Mn atom at C site. The energy levels appearing in the band gap due to vacancies and due to Mn impurities are determined and the calculated densities of states (DOSs) are used to analyse the different value of the magnetic moments for different types of substitution. A model that explains the magnetic moment at Mn site is proposed

Mössbauer Study of Weathered H-meteorite from the Desert of Oman

A number of meteorites from the desert of Oman, classified as H-chondrites, with known and unknown ages, were studied by using 57Fe Mössbauer spectroscopy to determine their Fe3+-bearing compositions. Mössbauer spectra measured at 78 K were composed of paramagnetic doublets superimposed on magnetic sextets. The doublets are assigned to the silicate minerals olivine and pyroxene and Fe3+ phases. The magnetic sextets in most samples showed the presence of at least three magnetic phases, namely troilite, magnetite and kamacite, which commonly exist in most ordinary chondrites. The relative amounts (area %) of Fe3+ in the known-age meteorites, determined from the Mössbauer spectra, were plotted against their terrestrial ages. The plot was used to estimate the terrestrial ages of meteorites with unknown terrestrial age