Dynamic surface tension and surface dilatational elasticity properties of mixed surfactant/protein systems

We present the study on dynamic surface tension and surface dilatational elasticity properties of dilute aqueous systems of pentaglycerol fatty acid esters (pentaglycerol monostearate, C18G5, and pentaglycerol monooleate, C18:1G5, whey protein, sodium caseinate, and mixed surfactant and protein at room temperature. The adsorption kinetics at the air-liquid interface has been studied by bubble pressure tensiometer and the oscillation bubble (rising drop) method. It has been shown that the dynamic surface tension curve basically presents two-regions; namely induction region and rapid fall region. During the induction time the adsorption is the diffusion-controlled process of amphiphilic surfactant or protein molecules from the bulk of the solution to the interface. Whey protein and sodium caseinate showed longer induction time approximately 10000 ms compared to the surfactant systems, where induction time was estimated to be approximately 1000 ms. However, in both the protein and surfactant systems, the induction time goes on decreasing with increasing the concentrations. The similar behavior was observed in the mixed system, and lower surface tension values were observed at higher concentrations. The fitting of the experimental data to the theoretical equation shows the presence of two relaxation mechanisms of widely different time scale for the adsorption of surfactant or protein molecules at the interface. The relaxation time strongly varies with the concentrations following the power law, and at fixed concentration it was the highest for whey protein and the lowest for C18:1G5 system. The surface dilatational elasticity determined within the frequency range of approximately 0.1 to 1 cycle/s supports the dynamic surface tension data.     

Aphananthe aspera kernel oil: A rich source of linoleic acid

The seed kernels ofAphananthe aspera Planch. yielded 50.8% of a pale yellow oil. The fatty acid composition determined by gas liquid chromatography was: 5.3% palmitic, 0.1% hexadecenoic, 3.0% stearic, 6.1% oleic, 85.1% linoleic, and 0.4% linolenic acids.     

Modification of cation exchange membrane by grafted poly(4-vinyl-N-methylpyridinium-iodide)

It is well known that cation exchange membranes, having a very thin layer of a cationic polyelectrolyte on the membrane surface, have preferential permselectivity for monovalent cations in a monovelent-divalent cations system. We studied the relationship between preferential permselectivity and molecular structure of the cationic polyelectrolyte. Grafted poly(4-vinyl-N-methylpyridinium-iodide) was used and was compared with poly(4-vinyl-N-methylpyridiniumiodide). The backbone polymers were poly(styrene-co-p-benzylstyrene) and poly(benzyl), onto which 4-vinylpyridine was grafted by anionic polymerization and then quaternized with CH₃I. The grafted poly(4-vinyl-N-methylpyridinium-iodide) is effective in making the cation exchange membrane preferentially permselevtive for Na⁺ - Ca²⁺ system and is more preferable than poly(4-vinyl-N-methylpyridinium-iodide) in terms of electric resistance of the membrane. However, the relationship between the molecular structure of the cationic polyelectrolyte and the durability of the preferential permselectivity is not clear.     

A full integration of electromagnetic resonance sensor and capacitive touch sensor into LCD

We have developed a transmissive and reflective LCD that integrates electromagnetic resonance (EMR) and capacitive touch sensors using existing in‐cell process. This development has been achieved by utilizing our hybrid‐in‐cell technology with low resistance material for the RX, which is an improvement of over 80% compared with conventional indium thin oxide (ITO) material. For EMR detection, we have slightly modified the TX layer used for capacitive touch sensing, by making a coil loop that generates a magnetic field on the panel. The direction of current on the coil can be modulated by the low‐temperature polycrystalline silicon (LTPS) circuit. Our in‐cell touch sensing has separately assigned timings for display and touch units. This time‐sharing method provides immunity from display noise and consequently better signal‐to‐noise ratio (SNR) than other out‐cell types. In parallel, we have developed a new controller that can support both EMR and capacitive sensing as a one‐chip solution, with the capability of maximizing signal levels lowering noise and detecting the frequency precisely when there is pressure on the pen tip. Our in‐cell technologies contribute not only a good SNR for EMR pen but also the added benefits for thin design, lightweight panel, compared with conventional LCD techniques.     

Selection of two arm-swing strategies for bipedal walking to enhance both stability and efficiency

Walking ability, which involves mainly stability and efficiency, is one of the most important issues in humanoid robots. Effective use of a robot’s arms is expected to improve its walking ability under its body constraints. Although several types of arm-swing strategies have been proposed, they are difficult to execute simultaneously. We propose two-stage integration of these strategies to enhance both stability and efficiency. A selection algorithm for locomotion (SAL) selects the appropriate strategy according to the demands of the situation. In the first stage, two strategies are evaluated. One of them, Ro-SAL, entails use and compensation of the moment of the swing leg by hip rotation and arm swing. The other strategy, Su-SAL, entails the support of center of gravity trajectory tracking based on a predictive control. Ro-SAL is effective for the stable state and states with internal model error, whereas Su-SAL is effective in states with external force and environmental complexity. In the second stage of the proposed method (AS-SAL), the robot recognizes the current state and selects the optimal combination of the two arm-swing strategies. As a result, a humanoid robot can exhibit more efficient, stable bipedal walking without falling.     

Novel front‐light system using fine‐pitch patterned OLED

Abstract— A novel front‐light system that uses an organic light‐emitting‐diode (OLED) light source patterned with a fine pitch has been developed. The front‐light system has the following characteristics: (1) excellent uniformity within the light‐emitting area; (2) emittance that is consistent at all viewing angles; (3) no light leakage at any viewing angle from the side of the observer. This system can be adopted for reflective LCDs, electrophoretic displays (EPDs), microelectromechanical systems (MEMS), and other applications.     

The corrosion behaviour of chromium in hydrogen chloride gas and gas mixtures of hydrogen chloride and oxygen at high temperatures

A kinetic investigation of the CrHClO₂ system at 1 atm was carried out varying the oxygen content from 0 to 75 vol% at 400–800°C by the thermogravimetric method in stagnant gases and by measurements of weight loss and weight of sublimates after corrosion tests in flowing gases. In hydrogen chloride gas the corrosion rate is determined by the rates of formation and evaporation of a CrCl₂ scale: the scale was protective, to some extent, up to 600°C, but rapidly evaporated at still higher temperatures. The addition of oxygen led to suppression of corrosion loss up to about 500°C but to catastrophic corrosion at higher temperatures. The scale formed in the gas mixtures consisted mainly of Cr₂O₃ but vigorous vaporization of CrCl₂ and water occurred at the higher temperatures due to oxy-chlorination.     

Drag minimization and lift maximization in laminar flows via topology optimization employing simple objective function expressions based on body force integration

This paper deals with topology optimization of body shapes in fluid flows, where some new ideas for drag minimization and lift maximization problems are proposed. For drag minimization problems, the objective function is expressed as a body force integration in the flow domain. Also a similar expression of objective function is given for lift maximization problems. Employing those objective function expressions, optimum shapes of bodies in incompressible axisymmetric and two-dimensional flows are numerically investigated.     

Enhancement of the Mie scattering effect using floatstone-like TiO2 spherical micropigment

Floatstone-like TiO₂ microparticles with an efficiently enhanced Mie scattering effect were developed by thermofusing of rutile-type TiO₂ submicron particles on the template core of poly(acrylate) microspheres. The light reflectance of the floatstone-like TiO₂ microparticles was approximately 10% higher than that of the usual rutile-type TiO₂ submicron particles in a wavelength range from 400 to 850 nm. The diffuse reflectance of the microparticles is enhanced by the formation of a floatstone-like structure, whereas there is no difference in the specular reflectance of the particles. As an application of the floatstone-like TiO₂ microparticles, the contribution of the particles to the light-trapping effect of a solar cell was examined. The power conversion efficiency of the solar cell was enhanced by 22% with the introduction of a light-scattering layer composed of the floatstone-like TiO₂ microparticles.     

3D Monte Carlo analysis of potential fluctuations under high electron concentrations

Potential fluctuations and hot electron effects associated with the Coulomb interaction among electrons are investigated with the self-consistent 3D MC simulations under the thermal equilibrium condition. It is demonstrated that the present simulations could successfully simulate the collective plasma waves owing to careful optimizations of simulation parameters. As a result, the potential fluctuations due to the plasma waves greatly disturb the local density of states and induce the band-tailing effects, which lead to the electron kinetic energy much larger than that of room temperature, whose magnitude coincides well with the previous results obtained from the 2D MC simulations.