Radial honeycomb core

Core alleviates many limitations of conventional nacelle construction methods. Radical core, made of metals or nonmetals, is fabricated either by joining nodes and then expanding, or by performing each layer and then joining nodes. Core may also be produced from ribbons or strips with joined nodes or ribbons oriented in longitudinal planes

Femtosecond probing of bimolecular reactions: The collision complex

Progress has been made in probing the femtosecond dynamics of transition states of chemical reactions.(1) The "half-collision" case of unimolecular reactions has been experimentally investigated for a number of systems and much theoretical work has already been developed.(2) For bimolecular reactions, the case of full collision, the zero of time is a problem which makes the femtosecond temporal resolution of the dynamics a difficult task

Femtosecond real-time probing of reactions. VIII. The bimolecular reaction Br+I2

In this paper, we discuss the experimental technique for real-time measurement of the lifetimes of the collision complex of bimolecular reactions. An application to the atom–molecule Br+I_2 reaction at two collision energies is made. Building on our earlier Communication [J. Chem. Phys. 95, 7763 (1991)], we report on the observed transients and lifetimes for the collision complex, the nature of the transition state, and the dynamics near threshold. Classical trajectory calculations provide a framework for deriving the global nature of the reactive potential energy surface, and for discussing the real-time, scattering, and asymptotic (product-state distribution) aspects of the dynamics. These experimental and theoretical results are compared with the extensive array of kinetic, crossed beam, and theoretical studies found in the literature for halogen radical–halogen molecule exchange reactions

Method of statistical filtering

Minimal formula for bounding the cross correlation between a random forcing function and the state error when this correlation is unknown is used in optimal linear filter theory applications. Use of the bound results in overestimation of the estimation-error covariance

Ab Initio study of neutron drops with chiral Hamiltonians

We report ab initio calculations for neutron drops in a 10 MeV external harmonic-oscillator trap using chiral nucleon-nucleon plus three-nucleon interactions. We present total binding energies, internal energies, radii and odd-even energy differences for neutron numbers N = 2 - 18 using the no-core shell model with and without importance truncation. Furthermore, we present total binding energies for N = 8, 16, 20, 28, 40, 50 obtained in a coupled-cluster approach. Comparisons with Green's Function Monte Carlo results, where available, using Argonne v8' with three-nucleon interactions reveal important dependences on the chosen Hamiltonian.Comment: 7 pages, 5 figure

Exploring the psychological rewards of a familiar semirural landscape: connecting to local nature through a mindful approach

This study analyses a 53,000 word diary of a year engaging with nature through over 200 trips to a semi-rural landscape. Thematic analysis revealed two themes; the transition from observer to nature connectedness and the ways in which the natural environment was experienced once a connection was made. These themes are discussed in relation to theories that seek to explain the positive effect of nature and nature connectedness. The findings are important as they suggest that repeated engagement with local semi-rural countryside can lead to a mindful approach and psychological rewards that do not require travel into the wilderness. The work informs further research into outcomes and processes of nature based interventions such as: trip frequency, duration and diary keeping