Detection of Phase Separation by FTIR in a Liquid-Crystal-Display Substrate Aluminoborosilicate Glass

The effect of heat treatment on the Fourier transform infrared spectrometry (FTIR) reflection peak position of the Si–O structural band near 1087 cm⁻¹ of a liquid-crystal-display substrate glass was investigated. The FTIR peak position shifted more slowly with heat-treatment time, and to a greater extent than expected, for the fictive temperature change. The isochronal shift of the FTIR peak as a function of the heat-treatment temperature exhibited a good correlation with the change of chemical durability in an HCl solution, suggesting that the infrared peak shift was the result of the phase separation induced by the heat treatment. The separated phase, with spherical particles ∼50 nm in diameter, was observed by scanning electron microscopy in a glass sample heat-treated at 750°C for 2500 h. The FTIR peak shift measurement appears to be a sensitive method for detecting the early stage of the glass-in-glass phase separation for borosilicate glasses.     

Adaptive range particle swarm optimization

This paper proposes a new technique for particle swarm optimization called adaptive range particle swarm optimization (ARPSO). In this technique an active search domain range is determined by utilizing the mean and standard deviation of each design variable. In the initial search stage, the search domain is explored widely. Then the search domain is shrunk so that it is restricted to a small domain while the search continues. To achieve these search processes, new parameters to determine the active search domain range are introduced. These parameters gradually increase as the search continues. Through these processes, it is possible to shrink the active search domain range. Moreover, by using the proposed method, an optimum solution is attained with high accuracy and a small number of function evaluations. Through numerical examples, the effectiveness and validity of ARPSO are examined.     

Preparation of nano-grained zirconia ceramics by low-temperature, low-pressure spark plasma sintering

Ce- and/or Y-doped zirconia nanopowders having average particle sizes ranging 12–18 nm have been synthesized by a technique based on mechanochemical processing (MCP). Despite their small particle size, the powders had excellent compactibility with green densities exceeding 50% achieved under a moderate uniaxial pressure of 150 MPa. Nearly fully dense ceramics having grain sizes of around 100 nm were successfully produced from these powders by spark plasma sintering (SPS) at temperatures of 1,050–1,150 °C for 5 min under pressures of 50–80 MPa; these temperatures and pressures are considerably lower than those required for achieving near full density with conventional nanopowders. Hardness and fracture-toughness measurements showed that the ceramics prepared by SPS had superior mechanical properties to those prepared by conventional pressureless sintering. It is argued that the high sinterability of the MCP nanopowders is ascribed to their ability to form uniform powder compacts under relatively low pressure, and that that ability in turn originates in two features of the MCP powders: absence of hard agglomeration and pseudo-spherical particle morphology.     

Improvement of Submerged Biofilter Process by Bioelectrochemical Method

A bioelectrochemical method was applied to a submerged biofilter process to improve its nitrogen removal performance. Packed beds of activated carbon submerged into the aerobic tank of the submerged biofilter process were used as the electrodes and support for attached microbial growth. The experiments were conducted under different temperatures, dissolved oxygen (DO) concentrations and electric currents. The results showed that nitrification and denitrification rates were enhanced by supplying oxygen and hydrogen, respectively, from the substratum through electrolysis of water. The nitrification and denitrification rates were increased with increasing electric current. The effects of electric current on nitrification and denitrification rates were clearly shown under lower bulk liquid DO concentration. There was an optimum DO concentration to give the largest nitrogen removal rate in the bioelectrochemical compartment. The optimum DO concentration was in the range of 1.5–2.0 g∕m3.     

Embedded atom potentials in fcc and bcc metals

A new embedded atom potential has been proposed in this paper. The potential is expressed by simple functions and is applicable to the molecular dynamics simulations of large atomic systems. The potential parameters are determined from the experimental data using the cohesive energy, Born stability, elastic constants, C₁₁,C₁₂ and C₄₄, the formation energy of a vacancy. In case of fcc the stacking fault energy is also used to fit parameters. The potential functions for copper, silver and gold for fcc metals and for bcc metals Nb, Ta and Va are presented.     

Highly Efficient Photoelectrocatalytic Decomposition of Biomass Compounds Using a Nanoporous Semiconductor Photoanode and an O2-Reducing Cathode with Quantum Efficiency Over 100

UV light-activated highly efficient photoelectrocatalytic decomposition of biorelated compounds and biowastes was successfully achieved by a Biophotochemical Cell (BPCC) comprising a nanoporous semiconductor film photoanode and an O₂-reducing cathode with high internal quantum efficiency over 100. Major decomposition reaction was dark auto-oxidation of the activated substrate radicals (R^?) by the bulk O₂ into CO₂ or/and to N₂. Photocatalytic decomposition of aqueous solutions of urea, ammonia, pig urine, and oxalic acid was investigated. Combination cells were fabricated comprising a photoanode/cathode unit for activation of organic compounds and a large volume chamber for autooxidation of activated substrates.     

SAR characterization inside intracranial tumors for case–control epidemiological studies on cellular phones and RF exposure

Epidemiological studies investigating whether mobile phone use is related to cancer risk have been conducted in many countries. The purpose of the work reported here was to introduce the dose metric in the exposure assessment, taking into account the spatial distribution of exposure. Distributions of specific absorption rate (SAR) inside 275 cases of brain tumors (participants in the Japanese epidemiological study) were estimated. Phones had been classified into four categories based on SAR distributions and technical specifications. Results were found to be highly dependent on phone categories. Contralateral tumors were generally categorized as non-exposed tumors (max SAR <2.5% of max SAR in the brain) and, for any phone category, the maximum SAR in 75% of the ipsilateral tumors was less than 15% of the maximum SAR in the brain. Three new exposure indices combining the duration and strength of exposure were created to be used in the Japanese epidemiological study on mobile phone use and the risk of gliomas and meningiomas.     

MPEG-2 AAC 5.1-Channel Decoder Software for a Low-Power Embedded RISC Microprocessor

Presented here is MPEG-2 AAC low complexity profile decoder software for a low-power embedded RISC microprocessor, NEC V830 (300 mW @133 MHz). Fast processing methods for IMDCT reduce execution time by 41% and help achieve real-time decoding of a 5.1-channel audio signal, while using only 64.7% of processor capacity.     

Three-dimensional densification measurement of Vickers-indented glass using digital holographic tomography

We have used digital holographic tomography (DHT) to study the refractive index (density) changes occurring under Vickers indentations in silica, soda-lime, and non-alkaline aluminoborosilicate glasses. The measurements confirm that the maximum refractive index (density) is not constant but increases with load up to 300 gf. At higher loads (500 gf and 1 kgf), a subsurface (median) crack in soda-lime glass is observed with no apparent surface trace. The appearance of this crack reduces the maximum refractive index (density) observed. In addition, the vertical cross section of the 3D refractive index (density) map has been successfully obtained using a square fiber sample and lateral observation. These results clearly demonstrate a promising potential of DHT to evaluate the shape and the density distribution of the structurally modified zone in a Vickers-indented glass.