A fully quantum mechanical calculation of the diffusivity of hydrogen in iron using the tight binding approximation and path integral theory

We present calculations of free energy barriers and diffusivities as functions of temperature for the diffusion of hydrogen in bcc-Fe. This is a fully quantum mechanical approach since the total energy landscape is computed using a new self consistent, transferable tight binding model for interstitial impurities in magnetic iron. Also the hydrogen nucleus is treated quantum mechanically and we compare here two approaches in the literature both based in the Feynman path integral formulation of statistical mechanics. We find that the quantum transition state theory which admits greater freedom for the proton to explore phase space gives result in better agreement with experiment than the alternative which is based on fixed centroid calculations of the free energy barrier. We also find results in better agreement compared to recent centroid molecular dynamics (CMD) calculations of the diffusivity which employed a classical interatomic potential rather than our quantum mechanical tight binding theory. In particular we find first that quantum effects persist to higher temperatures than previously thought, and conversely that the low temperature diffusivity is smaller than predicted in CMD calculations and larger than predicted by classical transition state theory. This will have impact on future modeling and simulation of hydrogen trapping and diffusion

Christian Devotional Meditation and Holistic Well Being

Holistic well-being is a concept that implies humans are multidimensional and require a broad approach to help them achieve life contentment and satisfaction. Spirituality, relationships, emotional functioning, and biology all play a part in achieving this life balance and satisfaction. Interpersonal neurobiology suggests that early life experiences can contribute to underdeveloped brain structures resulting in the diminished ability to form meaningful attachment relationships that help foster contentment as an adult. This ability to engage in positive and supportive relationships has impact on life and holistic well-being. Further, the inability to form close relationships, engage, and emotionally connect with others has impacted the church as whole, and can even impact one’s attachment to God. Church-based programs, therefore, are needed to foster holistic well-being. A 6-week program utilizing Christian meditation and mindfulness activities has been developed as a Christian sensitive approach to relationship and life enhancement, and holistic well-being

MobGeoSen: facilitating personal geosensor data collection and visualization using mobile phones

Mobile sensing and mapping applications are becoming more prevalent because sensing hardware is becoming more portable and more affordable. However, most of the hardware uses small numbers of fixed sensors that report and share multiple sets of environmental data which raises privacy concerns. Instead, these systems can be decentralized and managed by individuals in their public and private spaces. This paper describes a robust system called MobGeoSens which enables individuals to monitor their local environment (e.g. pollution and temperature) and their private spaces (e.g. activities and health) by using mobile phones in their day to day life