The dynamics of gas flow through spinning cone columns (SCCs) have been studied through Computational Fluid Dynamics (CFD) simulations, and the liquid flow characteristics on the rotating surfaces have been correlated through dimensional analysis. The CFD simulations have been carried out in the absence of liquid flow. Flow instabilities are predicted above a critical value of the hydraulic Rey...

Compared to conventional solar cells on a substrate, thin film GaAs cells show a higher efficiency at a lower thickness due to back surface reflection. The optimal cell thickness is 1.7 μm. Thin film cells can also be illuminated from the rear side with an efficiency only 15% (relative) lower than for front side illumination.

The thickness dependence of the order-to-disorder transition (ODT), measured by in situ grazing-incidence small-angle X-ray scattering (GISAXS), has been investigated in thin films of a symmetric polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) on a random copolymer (P(S-r-MMA)) grafted to the substrate where the interfacial interactions are balanced. With decreasing film thickness less than...

Measuring the changing thickness of a thin film, without a reference, using an atomic force microscope (AFM) is problematic. Here, we report a method for measuring film thickness based on in situ monitoring of surface roughness of films as their thickness changes. For example, in situ AFM roughness measurements have been performed on alloy film electrodes on rigid substrates as they react with ...

in order to reduce wear in gudgeon pin, bush and piston boss lubrication is done. oil used in national engine species was 10w40 with dynamic viscosity 5.5 mpa.s at 140 °c (the working temperature). in order to complete investigation the oil film hydrodynamics analysis in small end of connecting rod, a real full model engine with four cylinders has been simulated by avl excite5.1 software. in th...

Scanning- and colloidal-probe atomic force microscopy were used to study the mechanical properties of poly(L-lysine)/hyaluronan (PLL/HA)(n) films as a function of indentation velocity and the number of polymer deposition steps n. The film thickness was determined by two independent AFM-based methods: scratch-and-scan and newly developed full-indentation. The advantages and disadvantages of both...

The effect of impurities on the grain boundary melting of ice is investigated through an extension of Derjaguin-Landau-Verwey-Overbeek theory, in which we include retarded potential effects in a calculation of the full frequency-dependent van der Waals and Coulombic interactions within a grain boundary. At high dopant concentrations, the classical solutal effect dominates the melting behavior. ...

The stratification of thin liquid films formed from micellar solutions or latex suspensions can be explained by layer-by-layer destruction of a colloid crystal structure inside the film. The stepwise decrease of the film thickness is due to appearance and growth of dark spots (of less thickness) in the film. This phenomenon is analyzed in the present paper, and an explanation is proposed. The d...

Moisture absorption in model photoresist films of poly(4-hydroxystryene) (PHOSt) and poly(tert-butoxycarboxystyrene) (PBOCSt) supported on silicon wafers was measured by X-ray and neutron reflectivity. The overall thickness change in the films upon moisture exposure was found to be dependent upon the initial film thickness. As the film becomes thinner, the swelling is enhanced. The enhanced swe...

Liquid film thickness measurements under temperature-varying conditions in a two-phase flow are of great importance to refining our understanding of two-phase flows. In order to overcome the limitations of the conventional electrical means of measuring the thickness of a liquid film, this study proposes a three-electrode conductance method, with the device fabricated on a flexible printed circu...