Dissipation by adhesion hysteresis in dynamic force microscopy

Abstract

Power dissipation, as measured in dynamic force microscopy, is usually considered to be proportional to the energy lost in the contact process through the oscillation period. In the presence of adhesion hysteresis, the dissipation is not triggered in each oscillation and only a fraction of the cycles contributes to the dissipated power. We derive a simple analytical closed expression for the dissipated power versus the oscillation amplitude which is in good agreement with the results of numerical simulations. Our theoretical and numerical results predict the existence of two possible dissipation regimes. In the first one, the power dissipated is linear with the energy dissipated by the substrate as expected. In the second regime, a beating pattern appears, causing the fraction of cycles undergoing hysteresis to be inversely proportional to the energy dissipated. As a consequence, the measured power dissipation is a function of a characteristic dissipation length and it is not proportional to the energy lost in a single adhesion process.

Cujtlacochi. El cuitlacoche

“…Por otra parte, en un estudio realizado por Mata (1987), con mayas de Pixoy, Yucatán, se encontró que U. maydis es concebido como algo asociado con la Figura 23. Representación de teonanacatl (Sahagún 1979).…”

“…El cuitlacoche dentro del pensamiento mesoamericano Figura 24. Representación de nanacatl (Sahagún 1979).…”

“…Para acabar con esto, para detener la diarrea que causaron los hongos, axin 4 -cocido, ablandado-se coloca en el recto. En esta misma obra (Sahagún 1979), se menciona el cuitlacoche en el Libro 11, pero no en la sección donde se habla de las setas, sino en el Capítulo 13 "De todos los mantenimientos", párrafo segundo "de cómo se siembra y cultiva el maíz". Los co men ta rios, de por sí breves, sólo se hacen en náhuatl, no en castellano, por ello en esta versión (Sahagún 1985), no se encuentra dato alguno referido al cuitlacoche.…”

“…¿Y dónde queda el cuitlacoche? Si partimos de la información proporcionada por Sahagún (1979) es claro que en el centro de México, a inicios del siglo xvi, sólo se le ve como algo "incluido en la mazorca", es decir, sin autonomía cultural (Andrés Medina, com. pers.…”

Self-organization of adatom adsorption structure at interaction with tip of dynamic force microscope

“…Particularly, the experimental and theoretical data are obtained on structural instabilities, phase transformations, plastic dislocation, neck and adatom structures formation [7][8][9][10][11][12][13][14][15][16][17][18][19][20]. These processes are characterized by hysteresis of dependencies of adhesion force and potential energy surface on the tipsurface distance [11,16,[21][22][23][24] and by hysteresis of the sample stress vs strain curve [25].…”