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We report the electronic and magnetic properties along with the Curie temperature (

Background Patients' perceptions and beliefs about medicine are affected by their culture, tradition, socioeconomic status, peer influence, educational level, advertisements among other factors. Objective To explore the perception about medicines among the general public in different semi-rural areas of Nepal. Method Cross-sectional study was conducted at different locations within Kathmandu valley from July 2015 to December 2016; 385 individuals were approached using simple random sampling but only 260, aged 18 years and above, who were taking medicines for their health problems, completed the interviewer-administered survey. Their perceptions about medicines were studied using a structured questionnaire based on the WHO booklet "How to investigate the use of medicines by consumers" and analysed using SPSS version 22. Association between respondents' age, gender, education level and perception were statistically analysed using χ2 test and/or Fisher's exact test and multivariate analysis of variance. Result Sixty-one respondents (23.5%) were in age group 56-65 years. Patients' perceptions of medicine safety based on colour, shape, name of medicine, method of administration, compatibility, etc. was statistically different among respondents with regard to their level of education (p = 0.022). More individuals with lower education believed that expensive medicines were more effective (p0.001). Increased level of education made them more aware of negative consequences of reusing previous prescriptions (p=0.039). Conclusion Problems with knowledge about medicines were noted among lesser educated individuals. Based on findings, policy makers may develop educational strategies to increase awareness about medicines.

This paper focuses on the electronic and thermoelectric properties of monolayer MoS

To study the structural and electronic properties of cubical perovskite KCaF3, the first principles calculation within the full potential linearized augmented plane wave (FP-LAPW) method is applied. The exchange correlation effects are included through the GGA exchange potential. The calculated structural properties such as equilibrium lattice constant, the bulk modulus and its pressure derivative are in agreement with the published results of other authors. From our study we have found that the band gap of KCaF3 is 6.4 eV which is the indication of insulating behavior.The Himalayan Physics Vol. 6 & 7, April 2017 (100-103)

With the help of density functional theory calculations, we explored the recently synthesized double perovskite material Ca

A density functional theory (DFT) approach employing generalized gradient approximation (GGA) and the modified Becke Johnson (TB-mBJ) potential has been used to study the electronic and thermoelectric (TE) properties of ZrxHf1−x−yTayNiSn.

The ground state electronic properties of bulk (W) were studied within the density functional theory (DFT). We have also analyzed the momentum- (q-) dependent loss function, dielectric constant, and optical conductivity (OC) within TD-DFT random-phase approximation (RPA). The loss function is plotted in the energy range 0–55 eV. The energy loss function spectrum shows four prominent peaks, two lower peaks below along with two sharp peaks above 30 eV. The different nature of peaks depends on the momentum transfer q. The peak caused by interband transition showed a less pronounced dispersion. From the dielectric function curve we have predicted the plasmon excitation at around 1.75 eV and calculated the corresponding plasma frequency (ωp)=26.585×1014 s−1.

Glicksman’s viscous limit set of dimensionless parameters have been investigated using experimentally verifi ed computational fl uid dynamics model. Simulations have been performed for the two bubbling fl uidized beds with different particle sizes and densities. Dimensionless average pressure drops across the bed height, dimensionless pressure standard deviations and dimensionless relative pressures have been investigated as a function of dimensionless superfi cial gas velocities for the two beds. Fluctuation of solid volume fraction and contours of solid volume fraction have also been investigated at different dimensionless gas velocities. Time series data of the pressure fl uctuation and solid volume fraction are compared. The results indicate that the fl uid dynamic similarity between two beds holds up to particle Reynolds number of 15. After this, the bubble activities in the two beds start to deviate signifi cantly. The results of the work show that the analysis of solid volume fraction fl uctuation gives higher accuracy than time-series pressure fl uctuation when scaling the bubbling fl uidized bed within the viscous limit.

Using density functional theory (DFT) calculations, we investigated the electronic and magnetic properties of the Heusler compounds Co2TGe (T = Sc, Ti, V, Cr, Mn, Fe). Among the systems under investigation Co2CrGe and Co2MnGe have given 100% spin polarization at the Fermi energy (EF). Co2CrGe is the most stable half-metallic ferromagnets (HMFs) with an energy gap of 0.24 eV at the Fermi level (EF) in spin down channel. We have also found an increase in the total magnetic moments as T goes from Sc to Fe. The calculated magnetic moments for Co2CrGe and Co2MnGe are 3.999 µB and 5.00 µB respectively. Based on the local spin density approximation (LSDA) calculated results, we have predicted that the compounds Co2CrGe and Co2MnGe are HMFs. We have tried to study the HMFs in Co2ScGe, Co2TiGe, Co2VGe and Co2FeGe by using the local spin density approximation and Coulomb repulsion (U) (LSDA+U) when the simple generalized gradient approximation (GGA) or the LSDA fail.

We performed the structure optimization of Co2TiAl based on the generalized gradient approximation (GGA) and linearized augmented plane wave (LAPW) method. The calculation of electronic structure was based on the full-potential linear augmented plane wave (FP-LAPW) method and local spin density approximation exchange correlation LSDA+U. We also studied the impact of the Hubbard potential or onsite Coulomb repulsion (U) on electronic structure; the values are varied within reasonable limits to study the resulting effect on the physical properties of Co2TiAl system. The calculated density of states (DOS) shows that half-metallicity of Co2TiAl decreases with the increase in U values.

The electronic and magnetic structures of Mn films with thicknesses of up to 12 monolayers on Fe(001) are investigated by means of first-principles calculations, with a focus on the thicker films. The Mn films show an in-layer antiferromagnetic structure and couple antiferromagnetically to the Fe substrate. The magnetic moments at the Mn surface and at the Mn–Fe interface are significantly enhanced, as compared to the respective bulk values. Several surface states are found at the centre of the two-dimensional Brillouin zone, some of which might explain recent experimental scanning tunnelling spectroscopy results.

Materials with perovskite crystal structure represent an interesting class of materials which, due to their simple structures and unique electronic and dielectric properties, has a great potential for applications in various technological fields, such as mechanical, electro-optic and semiconducting. We perform calculation of density of states (DOS) and band structures for fluoride perovskite like RbMgF3 using the full potential linearized augmented plane wave (FP-LAPW) method. To calculate the electronic properties, the exchange-correlation potential has been applied by using the generalized gradient approximation (GGA). From the calculation the lattice parameter of RbMgF3 found to be 4.139 Å. The band gap of RbMgF3 through the electron energy bands by GGA is obtained as 7.6 eV showing insulating behavior which is in good agreement with the available experimental data as well as previously calculated results.Journal of Nepal Physical SocietyVolume 4, Issue 1, February 2017, Page: 23-26

The aim of this study is to develop a robust CFD model for predicting fluid dynamics in a gasification reactor. Experimental tests are performed. A cylindrical bed with pressure sensors is used in the experimental study. A series of simulations are performed using the commercial CFD tool ANSYS Fluent 12.1. A multi-fluid Eulerian model incorporating the kinetic theory of granular flow is applied in the simulations. Fluidized bed reactors in biomass gasification processes use steam as a fluidizing gas. High temperature makes it difficult to study the flow behaviour under the operating conditions. A cold flow model is constructed to study the fluid dynamics. Air at ambient conditions is used as the fluidizing gas for the cold model. The density and viscosity variation between air at ambient temperature and steam at high temperature results in different flow behaviour. The CFD model is developed to also be able to predict the flow behaviour of steam fluidized beds. Computational minimum fluidization velocity, bed expansion ratio pressure drop and pressure standard deviation agree well with experimental measurements. A computational model has been developed and validated against experimental data. The validated CFD-model can be useful in the study of flow behaviour of high temperature steam fluidized gasification reactors.