Epidermal Layers Characterisation by Opto-Magnetic Spectroscopy Based on Digital Image of Skin

According to the most literature data, the skin is usually observed as a simple structure with equivalent electrical model, which includes general properties of epidermis, basal membrane and dermis. In this paper, we analyzed the skin structure as a more complex system. Particularly we analyzed epidermis based on layers approach and its water organization in lipids ordered in sub-layers. Using opto-magnetic spectroscopy method, which is very sensitive to paramagnetic/diamagnetic properties of the tissue, we found out that nanowater structure ordering in lipids of epidermal layers play very important role in skin properties. We use bioimpedance as complementary and compatible method to opto-magnetic spectroscopy in skin characterization. In our investigation we found out the difference of the skin properties of the people who are drinking two different type of water (Z and N). We observed the significant difference in middle part of stratum granulosum, where water-lipid sub-layers exists. These results indicate importance of water nanolayers presence in epidermis and type of drinking water reflecting on human skin properties

Charge Transport Characteristics of High Efficiency Dye-Sensitized Solar Cells Based on Electrospun TiO2 Nanorod Photoelectrodes

In this report, dye-sensitized solar cells (DSSCs) with high energy conversion efficiencies were fabricated using TiO2 nanorods electrospun from a solution mixture of titanium n-propoxide and poly(vinyl acetate) in dimethyl formamide. Investigation of the charge transport characteristics of this unique type of DSSC disclosed that the efficiency of the DSSCs was enhanced by optimizing the nanorod morphology to facilitate charge transport. Our TiO2 nanorods have an intrinsically higher sensitizer loading capability than conventional TiO2 nanoparticles and have much slower recombination lifetimes compared to conventional nanoparticles. Long electron lifetime in nanorod electrode contributes to the enhanced effective photocarrier collection as well as the conversion efficiency. The electron transport behavior of nanorod photoelectrodes was further improved by TiCl4 post-treatment. The post-treatment reduces the pore volume of nanorod photoelectrodes while improving inter-rod connectivity and enhancing electron diffusion. The electron diffusion coefficient of post-treated nanorod was similar to 51% higher than that of an untreated one, leading to a charge collection efficiency that was 19% higher at a incident photonflux of 8.1 x 10(16) cm(-2) s(-1). Finally, the efficiency of nanorod-based DSSCs was optimized at a photoelectrode thickness of 14 mu m to achieve 9.52% under masked illumination of simulated solar light, AM 1.5 Global (V-oc = 761 mV, J(sc) = 17.6 mA cm(-2), fill factor = 70.0%)

Optical Properties of Rotationally Twinned Nanowire Superlattices

We have developed a technique so that both transmission electron microscopy and microphotoluminescence can be performed on the same semiconductor nanowire over a large range of optical power, thus allowing us to directly correlate structural and optical properties of rotationally twinned zinc blende InP nanowires. We have constructed the energy band diagram of the resulting multiquantum well heterostructure and have performed detailed quantum mechanical calculations of the electron and hole wave functions. The excitation power dependent blue-shift of the photoluminescence can be explained in terms of the predicted staggered band alignment of the rotationally twinned zinc blende/wurzite InP heterostructure and of the concomitant diagonal transitions between localized electron and hole states responsible for radiative recombination. The ability of rotational twinning to introduce a heterostructure in a chemically homogeneous nanowire material and alter in a major way its optical properties opens new possibilities for band-structure engineering