Photoelastic Effects in Phosphate Glasses

The stress-optical coefficients of RO-Pz05 glasses (R = Mg, Ca, Sr, Ba, and Zn) were measured, and the photoelasticity mechanisms were analyzed based on the equation expressing the relation among the photoelastic constants, the elastic moduli, and the refractive index of glasses. No simple relation was found between the stress-optical coefficient and the elastic modulus, indicating that the factor (p – q), where p and q are the Neumann strain-optical coefficients, is important. The change of (p – q) with glass composition is governed mainly by changes in the effect of the atoms, rather than the lattice. The atomic effect increases with decreasing radius of the divalent cation, except for Zn²⁺. The ZnO-containing glasses exhibit extraordinarily large atomic effects. The photo-elasticity mechanism is discussed in relation to the nature of the chemical bonds.     

A Ray-Tracing Analysis of ICRH in Tokamaks

Power deposition profiles generated by Ion Cyclotron Resonance Heating （ICRH） in non-circular tokamaks are studied using a ray-tracing technique. The simulation results for the Experimental Advanced Superconductor Tokamak （EAST） D-shaped plasma are presented. It is indicated that the spatial distributions of plasma parameters （plasma density, species temperature, minority ion concentration, etc.） have an significant influence on the power deposition profiles. The findings may be highly useful to the planned plasma heating and experiments in EAST.     

Energy‐Efficient Train Speed Profile Generator Combining Partial Energy‐Oriented Driving Approaches

One way of reducing the energy consumption of trains is to drive them in an energy‐efficient manner. There can be various driving patterns between two adjacent stops, or various speed profiles, because there is a gap called the running time supplement between the planned running time set in a timetable and the shortest possible running time of the train. Previous studies have proposed using up the supplement by changing the driving operation from powering to coasting at optimal points in terms of energy consumption. Others have shown that full use of regenerative braking helps save energy. In this study, we developed an energy‐efficient speed profile generator by combining these partial energy‐oriented driving approaches when the planned running time is given. We added this generator to existing shortest running time calculation software, so that it works for various vehicle and train route data. Numerical experiments showed that our profile provided superior performance compared to manually created ones for artificial and real data.     

Suppression of Surimi Gel Setting by Transglutaminase Inhibitors

Three types of salted meat paste (3% NaCl, 3% NaCl plus 0.66% NH₄Cl or 3% NaCl plus 0.2% EDTA) were prepared from high and second grade surimi, set at 30°C up to 4 br, and subsequently heated at 85°C for 30 min. The gel strength, crosslinking of myosin heavy chain (MHC) and ?-(γ-glutamyl)lysine (?-(γ-Glu)Lys) content were determined. With extended setting time, gel strength, crosslinking of MHC and the content of a crosslinked product, ?-(γ-Glu)Lys, increased markedly in the gel from the high grade surimi. Such changes were suppressed considerably in the presence of NH₄Cl and EDTA and were not observed in the gel prepared from second grade surimi. These results indicated an active participation of intrinsic transglutaminase in the setting process.     

LIQUID-PHASE PHOTOCATALYTIC REACTION ON TiO22 THIN FILM

The photocatalytic decomposition process on TiO₂ thin films, was modeled by taking the decay of illumination intensity via Lambert-Beer law into account. For the sake of experimental verification of the proposed model, Ti02 thin films were prepared on a glass substrate by a dip-coating method combined with a sol-gel process and the photocatalyuc activity of the thin films was evaluated by the decomposition of 2-propanol (IPA) in an aqueous solution under illumination of UV light source. The film thickness up to 1.4 μm increased with the withdrawal speed raised to the power 0.6 and was proportional to the number of application (i.e., repetition of dip-coating process). The TiO₂ gel films prepared by a dip-coating technique, were subject to firing at 500°C. The photocatalytic decomposition rate could be expressed apparently as first-order with respect to IPA concentration. The observed relationship between apparent first-order rate constant of decomposition and the film thickness could satisfactorily be explained by the proposed model.     

ε-(γ-Glutamyl)lysine Crosslink Distribution in Foods as Determined by Improved Method

Quantitative analysis of ε-(γ-glutamyl)lysine crosslink in 127 foods was achieved with a, preliminary separation by reverse phase-HPLC before o-phthalaldehyde derivatization to remove interfering peaks. ε-(γ-Glutamyl)lysine was detected in 96 foods and its contents ranged from 0.2 to 135 μmol/lOOg protein. High levels were found in fish paste products, processed fish, shellfish, meats and soybeans, and raw poultry organs. For fish and meats, the level of ε-(γ-glutamyl)lysine in processed foods and fish paste was relatively higher than that in raw materials. The improved procedure could be applied for screening materials with transglutaminase activities.     

Compositional Trends in Photoelastic Constants of Borate Glasses

The stress-optical coefficients of binary and ternary borate glasses were measured and the factor ( p·q ), where p and q are the Neumann strain-optical coefficients, was determined. As a modifier oxide was added to B₂O₃ glass, the stress-optical coefficient decreased monotonically. It was found that the stress-optical coefficient is determined mainly by the elastic modulus, but the factor ( p·q ) becomes significant when the content and polarizability of the modifier cation are high. It was also found that the factor ( p·q ) decreases when the content and polarizability of the modifier cation increase. The ( p·q ) was divided into the lattice effect and the atomic effect, and their compositional dependences were discussed.     

Chaos and bifurcation in numerical computation by the Runge-Kutta method

In this paper the chaotic phenomenon and bifurcation in numerical computation using the Runge-Kutta method to discretize the nonlinear differential equation are investigated. It is shown that the bifurcation condition in the discretized equation is given by the eigenvalue of the jacobian matrix of the original differential equation. As an example, the bifurcation and chaos when a second-order nonlinear equation is discretized by the Runge-Kutta method is investigated and it is shown that the scenario from a stable fixed point to chaos when the fourth-order Runge-Kutta method is applied is quite different from those of the second-order Runge-Kutta method     

Chaos induced by the generalized Euler method

In this paper, bifurcation and the chaotic phenomenon in numerical computation are investigated using the generalized Euler method. In this method, the forward and backward Euler methods and the trapezoidal method can be represented as special cases. It will be made clear that, for some computation step size, the solution of the difference equation does not always approximate to the solution of the original differential equation; period-doubling bifurcations and the chaotic phenomenon occur in the solution of the difference equation. Two examples are shown to illustrate the effect of step size.     

Gel Strength Enhancement by Addition of Microbial Transglutaminase during Onshore Surimi Manufacture

Surimi from Alaska pollock flesh was manufactured onshore with Microbial transglutaminase (MTGase). Effect of MTGase was investigated by evaluating breaking strength and deformation of gels from MTGase-treated surimi with and without setting at 30°C. Quantitative analysis of ε-(γ-glutamyl)lysine (GL) crosslink was also carried out to monitor the MTGase reaction. In set gels, breaking strength and GL crosslink increased, and myosin heavy chain decreased correspondingly with MTGase concentration. These changes were smaller in gels prepared without setting. Results suggest that surimi gel could be improved through the formation of GL crosslinks by added MTGase in surimi.