208,421 research outputs found
Life detection
Compact automated laboratory unit has 60 independently treatable culture chamber assemblies for metabolic studies of cultured microorganisms on the surface of Mars or other planets
Improved circuit-board interconnectors
One component serves three functions, electrical interconnections, thermal control, and mechanical integrity, at same time. Several versions of design: (1) Insulated support plate contains holes; (2) Alternate support plate configuration uses rivets instead of pins; and (3) Another configuration includes leaf-spring contacts instead of pins or rivets
Simulation of Material Properties Below the Debye Temperature: A Path-Integral Molecular Dynamics Case Study of Quartz
Classical and path integral molecular dynamics (PIMD) simulations are used to
study alpha-quartz and beta-quartz in a large range of temperatures at zero
external stress. PIMD account for quantum fluctuations of atomic vibrations,
which can modify material properties at temperatures below the Debye
temperature. The difference between classical and quantum mechanical results
for bond lengths, bond angles, elastic modulii, and some dynamical properties
is calculated and comparison to experimental data is done. Only quantum
mechanical simulations are able to reflect the correct thermomechanical
properties below room temperature. It is discussed in how far classical and
PIMD simulations can be helpful in constructing improved potential energy
surfaces for silica.Comment: 8 pages, 9 figures, submitted to J. Chem. Phy
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