How localized are energy dissipation processes in nanoscale interactions?

This paper presents a thermodynamic model for studying the energy dissipation processes such as friction, wear, and the adhesion phenomenon in order to predict the built-up layer (BUL) and built-up edge (BUE) formation conditions in dry cutting of SUS304 stainless steel. The model is composed of three parts: the extended representative contact model (RCM) at the tool and chip interface, the thermodynamic analysis within the RCM, and the growth model. At a typical region, the RCM is characterized by three material elements and two boundary elements, which support the contact conditions between two material elements. Thermodynamic analysis within the RCM reveals that apart from friction and wear, the BUL/BUE formation is also an irreversible energy dissipation process. The BUL/BUE can be called as a “dissipative structure substance,” which can reduce tool wear. Meanwhile, the RCM is an open system because it allows for the transfer of energy and matter with its surrounding. Energy exchange and mass exchange exert significant influences on the BUL/BUE growth. It is verified that the BUL/BUE growth depends significantly on four energy dissipation processes: workpiece fracture, friction, workpiece accumulation, and reduction of adhesion. In addition, the proposed model is verified by comparing simulations with the corresponding experimental results of dry cutting of SUS304 stainless steel. It is verified that the BUL/BUE develops its characteristics with cutting time and that the proposed model can accurately predict the BUL/BUE formation conditions. These results have provided a deeper understanding of the BUL/BUE formation mechanisms.

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Energy dissipation processes in scanning tunneling microscopy

Physical Review B ◽

10.1103/physrevb.34.2899 ◽

1986 ◽

Vol 34 (4) ◽

pp. 2899-2902 ◽

Cited By ~ 39

Author(s):

F. Flores ◽

P. M. Echenique ◽

R. H. Ritchie

Keyword(s):

Energy Dissipation ◽

Scanning Tunneling Microscopy ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Dissipation Processes

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Particle Acceleration in the Heliosphere

Highlights of Astronomy ◽

10.1017/s1539299600011308 ◽

1995 ◽

Vol 10 ◽

pp. 307-309

Author(s):

Loukas Vlahos

Keyword(s):

Particle Acceleration ◽

Energy Dissipation ◽

Electric Field ◽

Solar Surface ◽

Interplanetary Medium ◽

Acceleration Process ◽

Mhd Turbulence ◽

Dissipation Process ◽

Planetary Magnetospheres ◽

Dissipation Processes

The heliosphere could be divided in three major acceleration Laboratories, the solar surface (Laboratory 1), the interplanetary medium (Laboratory 2) and Earth and Planetary magnetospheres (Laboratory 3). Our understanding of the acceleration process depends strongly on the nature of the drivers and the energy dissipation process. The energy gain by a particle with velocity where is the variation of the electric field in space and time. All three Laboratories mentioned above share a common characteristic, the drivers and the energy dissipation processes are closely connected to fully developed MHD turbulence. We can show that our understanding of particle acceleration depends strongly on the interaction of particles with fields resulting from fully developed MHD turbulence.

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Energy Dissipation Processes of a Biological Protein in Condensed Phase.

The Review of Laser Engineering ◽

10.2184/lsj.31.195 ◽

2003 ◽

Vol 31 (3) ◽

pp. 195-201

Author(s):

Masahide TERAZIMA

Keyword(s):

Energy Dissipation ◽

Condensed Phase ◽

Dissipation Processes

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Photochemistry, energy dissipation and cold-hardening in Eucalyptus nitens and E. pauciflora

Functional Plant Biology ◽

10.1071/pp98027 ◽

1998 ◽

Vol 25 (5) ◽

pp. 581 ◽

Cited By ~ 6

Author(s):

Mark J. Hovenden ◽

Charles R. Warren

Keyword(s):

Electron Transport ◽

Energy Dissipation ◽

Low Temperatures ◽

Heat Dissipation ◽

Photosynthetic Electron Transport ◽

Thermal Dissipation ◽

Photon Flux ◽

Photon Flux Density ◽

Eucalyptus Nitens ◽

Dissipation Processes

The allocation of absorbed photon energy to thermal energy dissipation and photosynthetic electron transport was investigated as a function of photosynthetic photon flux density (PPFD) and temperature in two species of subalpine eucalypt, Eucalyptus nitens (Deane et Maiden) Maiden and E. pauciflora Sieb. ex Spreng. The proportion of absorbed light utilised in photosynthetic electron transport decreased with increasing PPFD, and the decrease was more pronounced the lower the temperature. The proportion diverted into dissipation processes increased with increasing PPFD to a maximum where it reached a plateau. This maximum increased with decreasing temperature. Exposure to a succession of cold (4˚C) nights increased the photochemical quantum yield of photosystem II and decreased the allocation of excitation energy to thermal dissipation processes in conditions of excess light, particularly at low temperatures. Consequently, the photosynthetic electron transport rate (ETR) was higher and heat dissipation rate (HDR) was lower in hardened plants than in non-hardened plants at low temperatures. At 20˚C, ETR was generally higher than HDR in all plants, but as the temperature decreased, HDR became the dominant process. The PPFD at which HDR exceeded ETR decreased with decreasing temperature, and at low temperatures was always lower in non-hardened plants than hardened plants, although quite similar between species.

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Electron beam scattering in an organic specimen

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108179 ◽

1978 ◽

Vol 36 (1) ◽

pp. 206-207

Author(s):

Ilesanmi Adesida

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Electron Beam ◽

Energy Dissipation ◽

Primary Electron ◽

Organic Sample ◽

Direct Technique ◽

Beam Scattering ◽

Dissipation Processes ◽

Scanning Electron

The understanding of electron-solid interactions is of prime importance to both conventional transmission and scanning electron microscopists. Monte Carlo simulation of electron beam scattering in various target samples has made fundamental contributions to this understanding, especially in scanning electron microscopy where primary electron beams of a few to many kilovolts are utilized. A significant example is the understanding of energy dissipation patterns of incident electrons in an organic sample (polymethylmethacrylate-PMMA) which is very useful in electron beam lithography (1). Furthermore, with the close similarity between the organic sample and a biological specimen, a Monte Carlo approach is also very useful for the study of energy dissipation in biological specimens (2).To enhance our knowledge of these dissipation processes, a more comprehensive Monte Carlo simulation program has been developed. The program is based on the semi-direct technique of simulating individual inelastic scattering and elastic scattering with probabilistic weightings.

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