Retarding spreading of surfactant drops on solid surfaces: Interplay between the Marangoni effect and capillary flows

AbstractThin films (1-24 layers) of bis-zinc ethane-bridged porphyrin dimer (1) have been transferred on solid surfaces, by the Langmuir- Schäfer (LS) horizontal method. The related surface pressurearea isotherm curve shows that in dependence of the film pressure different condensed phases may occur in the monolayer. The inspection of the monolayer by Brewster Angle Microscopy (BAM) reveals the presence of peculiar networks whose structural features seemingly change upon film compression. On the other hand, the Scanning Force Microscopy (SFM) analysis performed on LS films shows fractal networks constituted by nanoscopic supramolecular aggregates, whose shape and size depend again on the LS deposition surface pressure. Finally, also UV-vis spectroscopy measurements indicates that the absorption is almost linearly related to the film thickness that is directly connected to the surface pressure.

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Dynamic laser doppler velocimetry on solid surfaces

International Congress on Applications of Lasers & Electro-Optics ◽

10.2351/1.5058429 ◽

1991 ◽

Author(s):

Milind M. Rajadhyaksha ◽

Warren H. Stevenson

Keyword(s):

Laser Doppler Velocimetry ◽

Laser Doppler ◽

Solid Surfaces ◽

Doppler Velocimetry

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Selection of Wear Resistive Nano coating in En8 Steel

Bulletin of Scientific Research ◽

10.34256/bsr1929 ◽

2019 ◽

Vol 1 (2) ◽

pp. 73-80

Author(s):

Ilangkumaran M ◽

Tiruvenkadam N ◽

Saranya M ◽

Thulsidharan R

Keyword(s):

Mild Steel ◽

Mechanical Action ◽

Medium Carbon Steel ◽

Solid Surfaces ◽

Material Surface ◽

Multi Criteria Decision Making ◽

Sliding Surface ◽

Medium Carbon ◽

Nano Coating ◽

Selection Of

Where is the abrasive or gradual removal of materials at solid surfaces? It is caused due to the interaction between the sliding surface by mechanical action. The abrasive wears can be recognised as scratches or grooves. To enhance the wear resistance suitable nanocoating is applied on the material surface for better tribological properties such as hardness and toughness. Wear resistant nanocoating is used to reduce or eradicate wear to extend the lifetime of the EN8 steel. EN8 is unalloyed medium carbon steel with better mechanical properties than mild steel and also readily machinable in any condition. The nanocoating materials such as Al2O3, TiO2, SiC, ZrO2, WS2, Si3N4 etc., are used to reduce wear and to enhance hardness and toughness on mild steel through various nanocoating techniques. This paper deals with selection of suitable nanocoating material through AHP (Analytical hierarchal process) - a multi-criteria decision-making method.

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