Temporal and latitudinal variations of the length-scales and relative intensities of the chromospheric network

2018 ◽  
Vol 478 (4) ◽  
pp. 5056-5062 ◽  
Author(s):  
K P Raju
Keyword(s):  
Length Scales ◽  
Chromospheric Network ◽  
Latitudinal Variations

An Analytical Thermodynamic Approach to Friction of Rubber on Ice

2012 ◽  
Vol 40 (2) ◽  
pp. 124-150
Author(s):  
Klaus Wiese ◽  
Thiemo M. Kessel ◽  
Reinhard Mundl ◽  
Burkhard Wies
Keyword(s):  
Coefficient Of Friction ◽  
Liquid Layer ◽  
Contact Area ◽  
Leading Edge ◽  
Viscous Friction ◽  
Analytical Approximation ◽  
Real Contact Area ◽  
Length Scales ◽  
Real Contact ◽  
Ice Surface

ABSTRACT The presented investigation is motivated by the need for performance improvement in winter tires, based on the idea of innovative “functional” surfaces. Current tread design features focus on macroscopic length scales. The potential of microscopic surface effects for friction on wintery roads has not been considered extensively yet. We limit our considerations to length scales for which rubber is rough, in contrast to a perfectly smooth ice surface. Therefore we assume that the only source of frictional forces is the viscosity of a sheared intermediate thin liquid layer of melted ice. Rubber hysteresis and adhesion effects are considered to be negligible. The height of the liquid layer is driven by an equilibrium between the heat built up by viscous friction, energy consumption for phase transition between ice and water, and heat flow into the cold underlying ice. In addition, the microscopic “squeeze-out” phenomena of melted water resulting from rubber asperities are also taken into consideration. The size and microscopic real contact area of these asperities are derived from roughness parameters of the free rubber surface using Greenwood-Williamson contact theory and compared with the measured real contact area. The derived one-dimensional differential equation for the height of an averaged liquid layer is solved for stationary sliding by a piecewise analytical approximation. The frictional shear forces are deduced and integrated over the whole macroscopic contact area to result in a global coefficient of friction. The boundary condition at the leading edge of the contact area is prescribed by the height of a “quasi-liquid layer,” which already exists on the “free” ice surface. It turns out that this approach meets the measured coefficient of friction in the laboratory. More precisely, the calculated dependencies of the friction coefficient on ice temperature, sliding speed, and contact pressure are confirmed by measurements of a simple rubber block sample on artificial ice in the laboratory.

Lossless Photon management – Optical design for manufacture at different length scales - NOLOSS - H2020

Impact ◽  
2018 ◽  
Vol 2018 (1) ◽  
pp. 48-50
Author(s):  
Toralf Scharf ◽  
Paul Urbach ◽  
Carsten Rockstuhl ◽  
Frank Setzpfand
Keyword(s):  
Optical Design ◽  
Length Scales ◽  
Design For Manufacture ◽  
Photon Management

Strain tuned high thermal conductivity in boron phosphide at nanometer length scales – a first-principles study

2020 ◽  
Vol 22 (36) ◽  
pp. 20914-20921 ◽  
Author(s):  
Rajmohan Muthaiah ◽  
Jivtesh Garg
Keyword(s):  
Thermal Conductivity ◽  
First Principles ◽  
High Thermal Conductivity ◽  
Biaxial Strain ◽  
Length Scales ◽  
First Principles Study ◽  
Boron Phosphide

We report novel pathways to significantly enhance the thermal conductivity at nanometer length scales in boron phosphide through biaxial strain.

scholarly journals Hybrid fluorescence-AFM explores articular surface degeneration in early osteoarthritis across length scales

2021 ◽  
Author(s):  
Mathaeus Tschaikowsky ◽  
Tanja Neumann ◽  
Sofia Brander ◽  
Heiko Haschke ◽  
Bernd Rolauffs ◽  
...  
Keyword(s):  
Articular Surface ◽  
Early Osteoarthritis ◽  
Length Scales

scholarly journals Correlating nanoscale secondary ion mass spectrometry and atom probe tomography analysis of uranium enrichment in metallic nuclear fuel

The Analyst ◽  
2021 ◽  
Vol 146 (1) ◽  
pp. 69-74
Author(s):  
Elizabeth Kautz ◽  
John Cliff ◽  
Timothy Lach ◽  
Dallas Reilly ◽  
Arun Devaraj
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Fuel ◽  
Atom Probe Tomography ◽  
Secondary Ion Mass Spectrometry ◽  
Atom Probe ◽  
Uranium Enrichment ◽  
Length Scales ◽  
Atom Probe Tomography Analysis ◽  
Secondary Ion ◽  
Tomography Analysis

235U enrichment in a metallic nuclear fuel was measured via NanoSIMS and APT, allowing for a direct comparison of enrichment across length scales and resolutions.

scholarly journals Hydrodynamic and Ballistic Transport over Large Length Scales in GaAs/AlGaAs

2021 ◽  
Vol 126 (7) ◽  
Author(s):  
Adbhut Gupta ◽  
J. J. Heremans ◽  
Gitansh Kataria ◽  
Mani Chandra ◽  
S. Fallahi ◽  
...  
Keyword(s):  
Ballistic Transport ◽  
Length Scales ◽  
Large Length
Sign in / Sign up

Export Citation Format

Share Document