Numerical investigation of zoomable holographic projection without a zoom lens

Holographic projection is for laser displays and has the merits of being aberration free, producing high‐contrast images, having the ability of color reconstruction with one spatial light modulator, and so on. In this paper, we propose a zoomable holographic projection without using a zoom lens and verify the proposed method by using numerical simulation. Although such a system can be readily realized to use the features of holography, which is capable of recording a large image exceeding the hologram size, the required calculation is very time consuming. For acceleration, we used shifted Fresnel diffraction for setting different sampling rates on a hologram and projected image. The proposed method can project any zoom‐in and zoom‐out image between zeroth‐order and first‐order lights, and the processing time and required memory for the zoom are constant.     

Electrochemical characteristics for redox systems at nano-honeycomb diamond

Electrochemical characteristics for several redox systems at diamond films with highly ordered nanometer-scale cylindrical pores (‘nano-honeycombs’) were examined with cyclic voltammetry (CV) and electrochemical impedance measurements. The cyclic voltammetric anodic-cathodic peak separations for these nano-honeycomb electrodes were in the same range as those for polished polycrystalline diamond films, indicating that the involvement of the oxygen-terminated surface of the nano-pore walls, which should give rise to large peak separations for certain redox couples was only slight. Moreover, the peak currents in the CV were not enhanced to the extent expected on the basis of the roughness factors of the nano-honeycomb films. Ac impedance plots results indicated the existence of a concentration gradient of the reactant in the nano-pores, which is in agreement with theoretical predictions for charge transfer reactions in porous electrodes. The average concentration of the reactant (Fe^2+/3+) inside the nano-pores was a factor of ca. 80 lower than that in the bulk electrolyte. The results of the impedance analysis also indicated an increase in the reaction resistances with decreasing pore diameters.     

Concentration of acetic acid in sulfite pulp evaporation drain by reverse osmosis

The evaporation drain of sulfite pulp spent liquor contains few volatile fatty acids, most of which is acetic acid. The main objective of this study is to recover acetic acid as the concentrated solution (about 4%), which could be used as a culture medium of the yeast. As acetic acid can easily pass through the cellulose acetate membrane, SP drains neutralized by NaOH, NH₄OH and Ca(OH)₂ were used as the feed solutions. In all cases, concentration by reverse osmosis was successfully carried out provided the appropriate pretreatment was employed. The recovery of acetic acid was 95.6, 90.5 and 98.2% for Na-, NH₄-, and Ca-drain, respectively. In addition, the recovered (permeated) water may be used as an industrial one.     

Polymerization of methyl methacrylate by tri-n-butylborane in the presence of amino acid esters

The polymerization of methyl methacrylate by tri-n-butylborane in the presence of amino acid esters was investigated. The binary systems of tri-n-butylborane and amino esters were found to be more effective for initiating the polymerization than tri-n-butylborane alone. Co-catalytic effects of amino acid esters were in the order: tyrosinate > glutamate > aspartate ? phenyl alaninate > serinate > glycinate. The rate of polymerization in a mixture of dimethylsulphoxide and toluene was proportional to the square root of the concentration of the initiator system, to the monomer concentration, and to the concentration of dimethylsulphoxide in the solvent. The overall energy of activation was estimated to be 4.6 kcal/mol for the tri-n-butylborane/methyl tyrosinate system. Copolymerization curves gave a typical free-radical character.     

Copolymerization of phenylacetylene with various acetylenes by W- and Mo-based catalysts

In the copolymerization of phenylacetylene with various acetylenes catalysed by WCl₆·Ph₄Sn, the relative reactivity of monomer decreased with increasing steric effect of monomer, e.g. HC  Cn-Bu, HC  Cn-Hex > HC  CPh, HC  Cs-Bu > HC  Ct-Bu, MeCCPh, CICCPh. While 1-chloro-2-phenylacetylene (a disubstituted acetylene) showed high reactivity in the homopolymerization by Mobased catalysts, the reactivity was remarkably depressed in the presence of phenylacetylene as comonomer. Based on these results, the relative reactivity of the acetylenic monomers in copolymerization was explained in terms of competitive coordination of monomers to the propagating end.     

Development of a high‐resolution RGBW flexible display using a white organic light‐emitting diode with microcavity structure and that of a side‐roll touch panel

In this study, white organic electroluminescent devices with microcavity structures were developed. A flexible high‐resolution active‐matrix organic light‐emitting diode display with low power consumption using red, green, blue, and white sub‐pixels formed by a color‐filter method was fabricated. In addition, a side‐roll touch display was developed in combination with a capacitive flexible touch screen.     

Melt viscosity and flow birefringence of polycarbonate

Melt viscosity and flow birefringence of bisphenol A-type polycarbonate were measured and analyzed by the application of rubber-like photoelastic theory. The melt viscosity in the Newtonian flow region increased with the molecular weight to the power of 3.4. In polycarbonate, the shear stress of the Newtonian flow region was to 10⁶ dyn/cm², whereas in PMMA it was at most 3 = 10⁵ dyn/cm². The flow birefringence δn has a linear relation with shear stress S, that is δn = 5.7 × 10^?10 S. The principal polarization difference of flow unit α₁ – α₂ was 1.62 × 10^?23 cm³, which was obtained by the application of the rubber-like elastic theory. In PMMA, it was 3.9 = 10^?25 cm³; about 1/40 of that was polycarbonate. The anisotropy of polarizability of the flow unit of polycarbonate was also about 40 times larger than that of PMMA. So the anisotropy reflected the large flow birefringence of the polycarbonate.     

Interfacial tension of demixed polymer solutions near the critical temperature: polystyrene + methylcyclohexane

Interfacial tension between demixed solutions of polystyrene + methylcyclohexane has been measured near the critical temperature as a function of temperature using polystyrenes with molecular weights 9000 ～ 1.26 × 10⁶. The critical exponent for the interfacial tension was determined to be about 1.30 for the lower molecular weight systems. However, for higher molecular weights the exponent could not be obtained because the system departed from critical behaviour. Magnitudes of the interfacial tension were proportional to about N^?0.44, where N is the polymerization index. Experimental results were compared with the recently-proposed theories and found to be in qualitative agreement. The tricritical theory of polymer solutions was also compared with the experimental results.     

A superconducting filter to separate an oxygen and argon mixture

Hot isostatic pressing in an oxygen atmosphere, known as O₂-HIP method, has been used successfully to synthesize oxide materials, as well as to produce porous materials. In this paper a porous superconducting oxide is synthesized by this method and its application as a gas filter is described. Porous superconductors can be used to separate a mixture of paramagnetic and diamagnetic gases, such as oxygen and argon. Separation occurs after a magnetic field is applied and is based on the Meissner effect. Experimental results showed that the oxygen content of an oxygen/argon mixture increased after passing through a filter with large pore size (about 10 m).