Ab-initio insights into the structural, elastic, bonding, and thermophysical properties of UHx (x = 1, 2, 3, 5, 6, 7, 8) under pressure: possible relevance to high-Tc superconductivity

Binary uranium hydrides, UHx (x = 1, 2, 3, 5, 6, 7, 8), with different crystal symmetries are potentially interesting compounds for high-Tc superconductivity and as hydrogen storage systems. In this work we have explored the structural, elastic, mechanical, bonding, and thermophysical properties of these systems under uniform pressure via density functional theory based computations. Most of the results disclosed in this work are novel. From the calculations of the cohesive energy and enthalpy of formation, we have found that the titled compounds are chemically stable. The computed elastic constants at different pressures ensure elastic stability. All the binary hydrides are mechanically anisotropic. Pressure induced brittle-ductile transition takes place under high pressure. The compounds are machinable with the cubic {\alpha}-UH3-Pm-3n showing very high value of the machinability index. All the compounds are fairly hard with cubic UH8 showing superhard character. The Debye temperatures and acoustic velocities of these compounds are high; the highest value is found for the cubic UH8. The melting temperature, Gr\"uneisen parameter, minimal phonon thermal conductivity, and the thermal expansion coefficient of these compounds have also been studied at different pressures. All these parameters show excellent correspondence with the estimated Debye temperature, elastic parameters and bonding characteristics

Molecular Basis of Triple Negative Breast Cancer and Implications for Therapy

Triple negative breast cancer is an aggressive form of breast cancer with limited treatment options and is without proven targeted therapy. Understanding the molecular basis of triple negative breast cancer is crucial for effective new drug development. Recent genomewide gene expression and DNA sequencing studies indicate that this cancer type is composed of a molecularly heterogeneous group of diseases that carry multiple somatic mutations and genomic structural changes. These findings have implications for therapeutic target identification and the design of future clinical trials for this aggressive group of breast cancer

First-principles pressure dependent investigation of the physical properties of KB2H8: a prospective high-TC superconductor

Using the density functional theory (DFT) based first-principles investigation, the structural, mechanical, hardness, elastic anisotropy, optoelectronic, and thermal properties of cubic KB2H8 have been studied within the uniform pressure range of 0 - 24 GPa. The calculated structural parameters are in good agreement with the previous theoretical work. The compound KB2H8 is found to be structurally and thermodynamically stable in the pressure range from 8 GPa to 24 GPa. Single crystal elastic constants Cij and bulk elastic moduli (B, G and Y) increase systematically with pressure from 8 GPa to 24 GPa. In the stable phase, KB2H8 is moderately elastically anisotropic and ductile in nature. The compound is highly machinable and fracture resistant. The Debye temperature, melting temperature and thermal conductivity increases with pressure. The results of electronic band structure calculations and optical parameters at different pressures are consistent with each other. The compound is optically isotropic. The compound KB2H8 has potential to be used as a very efficient solar energy reflector. The electronic energy density of states at the Fermi level decreases systematically with increasing pressure. The same trend is found for the repulsive Coulomb pseudopotential. Possible relevance of the studied properties to superconductivity has also been discussed in this paper

Ab-initio insights into the mechanical, phonon, bonding, electronic, optical and thermal properties of hexagonal W2N3 for potential applications

We investigated the structural, elastic, electronic, vibrational, optical, thermodynamic and a number of thermophysical properties of W2N3 in this study using DFT based formalisms. The mechanical and dynamical stabilities have been confirmed. The Pugh and Poisson ratios are located quite close to the brittle to ductile borderline. The electronic band structure and energy density of states show metallic behavior. The Fermi surface features are investigated. The analysis of charge density distribution map clearly shows that W atoms have comparatively high electron density around than the N atoms. Presence of covalent bondings are anticipated. High melting temperature and high phonon thermal conductivity at room temperature of W2N3 imply that the compound has potential to be used as a heat sink system. The optical characteristics demonstrate anisotropy for W2N3. The compound can be used in optoelectronic device applications due to its high absorption coefficient and low reflectivity in the visible to ultraviolet spectrum. Furthermore, the quasiharmonic Debye model is used to examine temperature and pressure dependent thermal characteristics for the first time.Comment: Submitted to Journal of Alloys and Compound