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Corona, flame, atmospheric plasma, and liquid flame spray (LFS) techniques were used to create highly hydrophilic surfaces for pigment-coated paper and board and machine-glossed paper. All the surface modification techniques were performed continuously in ambient atmosphere. The physical changes on the surfaces were characterized by field emission gun-scanning electron microscopy (FEG-SEM), atomic force microscopy and Parker Print-Surf surface roughness. The chemical changes were analysed by X-ray photoelectron spectroscopy. The superhydrophilic surfaces, i.e. contact angle of water (CAW)

We compare predictions of effective medium theories with the results of numerical modeling of linear optical properties of two-dimensional disordered dielectric structures. A type of Maxwell Garnett effective medium theory is found to be in good agreement with the results of the plane-wave-expansion computations for pseudo-random samples of nanoscale cylindrical rods in a host medium, except for very high volume fractions of the rods. We analyze the extent and the reasons of the deviations of the effective medium theory from the numerical results, as well as the degree of applicability of our numerical model to real random samples of porous dielectrics.

Nanostructured coatings have been prepared on a flexible, moving paperboard using deposition of ca. 40-nm-sized titanium dioxide nanoparticles generated by a liquid flame spray process, directly above the paperboard, to achieve improved functional properties for the material. Properties such as surface wettability can be extensively improved by a thin layer of nanoparticles on the substrate. Owing to the vulnerability to heat, the substrate needs to be moved rapidly through the flame. This, on the other hand, generates a setting for a roll-to-roll coating process, which favors upscaling of the method. In this article, we characterize the flame process for nanoparticle coating and quantify the operational window for this method. The amount of deposited material as a function of substrate speed through the flame is discussed. Although the thermophoretic flux of nanoparticles is estimated to be very high from the hot flame onto the cold substrate, other factors were observed to limit the deposited amount of ...

A formalism based on dyadic Green functions is applied to the reflection and transmission of fields generated in the presence of anisotropic media. Our approach is general and treats the fields immediately in terms of s- and p-polarized components. Hence, the Fresnel reflection and transmission coefficients appear naturally in our expressions. The asymptotic far-field expansions of the dyadic Green functions are easily obtained, and numerical calculations in experimental geometries are straightforward.

We show that surface plasmon resonance reflectance measurement can be used to extract the effective complex refractive index of a Bruggeman nanoliquid, i.e. a solution consisting of spherical nanop...