Effect of Filler Composition on the Brazing of Alumina to Copper Using Ultrasonic Wave

An ultrasonic wave was applied during brazing of alumina to Cu. First alumina was metallized by applying ultrasonicwave in braze bath. Then the metallized alumina was brazed with Cu using the same filler alloy. The filler used wereZn-Al alloys and Zn-Sn A     

Identification and field evaluation ofAnomala octiescostata (Coleoptera: Scarabaeidae) sex pheromone

Using GC-EAD, the sex pheromone of the scarab beetleAnomala octiescostata was identified to be a 8:2 binary mixture of (R,Z)-5-(–)-(oct-1-enyl)oxacyclopentan-2-one and (R,Z)-5-(–)-(dec-1-enyl)oxacyclopentan-2-one. These semiochemicals have been also reported as sex pheromone constituents of otherAnomala species, either geographically or seasonally isolated fromA. octiescostata. Synthetic sex pheromone was highly attractive in the field; 0.1 mg captured significantly more males than two virgin females. Buried traps were significantly more attractive than those positioned at 30, 90, and 150 cm above the ground. In a dose-response test (0.1–100 mg), no saturation due to overdose of pheromone was observed, but in most cases, two dosages differing by 10-fold were not significantly different. Response of males to traps baited with different ratios of the two components was tested in two experiments with randomized blocks and Latin-square designs. Deviation from the natural ratio (8:2) of sex pheromone did not significantly diminish the response of males. Peak flight activity of beetle was recorded at 9:00–10:00 AM JST on sunny days in the end of April 1993.Presented in part at the 10th Annual ISCE Meeting, July 31–August 4, 1993, Clearwater Beach, Florida.     

An efficient method for the two-dimensional elastostatic boundary element method

In order to obtain accurate results and to reduce computation time, we have proposed in this paper a new strategic method, where quadratic elements are used at the corner points and linear elements at the points off the corner points. A computer program using this method has been developed and applied to several problems of various shapes. The usefulness of this method was illustrated by the application results.     

Stability of Skutterudite Thermoelectric Materials

By multifilling with La, Ba, Ga, Ti, Yb, Ca, Al, and In, the dimensionless figure of merit ZT of filled skutterudites has been improved in this work. ZT reached 0.75 for p-type (La,Ba,Ga,Ti) _x (Fe,Co)₄Sb₁₂ (x = 0.8 to 1.0) and 1.0 for n-type (Yb,Ca,Al,Ga,In) _y (Co,Fe)₄Sb₁₂ (y = 0.7 to 0.9). After annealing at 873 K for 180 h, 300 h, 710 h, 1000 h, and 5000 h in vacuum, the Seebeck coefficient S and the electrical resistivity ρ of the samples increased while the thermal conductivity λ decreased with increasing annealing time. As a result, the ZT values of both p- and n-type skutterudites remained unchanged or were slightly improved, demonstrating the excellent thermal stability of these skutterudites.     

The geodesic dynamic relaxation method for problems of equilibrium with equality constraint conditions

This paper presents an extension to the existing dynamic relaxation method to include equality constraint conditions in the process. The existing dynamic relaxation method is presented as a general, gradient‐based, minimization technique. This representation allows for the introduction of the projected gradient, discrete parallel transportation and pull back operators that enable the formulation of the geodesic dynamic relaxation method, a method that accounts for equality constraint conditions. The characteristics of both the existing and geodesic dynamic relaxation methods are discussed in terms of the system's conservation of energy, damping (viscous, kinetic, and drift), and geometry generation. Particular attention is drawn to the introduction of a novel damping approach named drift damping. This technique is essentially a combination of viscous and kinetic damping. It allows for a smooth and fast convergence rate in both the existing and geodesic dynamic relaxation processes. The case study was performed on the form‐finding of an iconic, ridge‐and‐valley, pre‐stressed membrane system, which is supported by masts. The study shows the potential of the proposed method to account for specified (total) length requirements. The geodesic dynamic relaxation technique is widely applicable to the form‐finding of force‐modeled systems (including mechanically and pressurized pre‐stressed membranes) where equality constraint control is desired. Copyright © 2014 John Wiley & Sons, Ltd.     

Risk hedging against the fuel price fluctuation in energy service business

Energy service business, or energy service company (ESCO), is expanding among industrial users as a means of energy saving. The ESCO business normally tends to become a long-term operation. During the operation, fluctuations of fuel and electricity costs significantly impact on the stability of the profit from ESCO business. Therefore, it is essential to reduce the risk of fuel and electricity cost fluctuations. Generally, a transaction called “financial derivative” is used as a measure of hedging against the fuel price fluctuation. In the case of ESCO business, it is necessary to manage the risk of both electricity and fuel price fluctuations because the variation in electricity price strongly affects the profit from ESCO as that in fuel price does.     

Characterization of electrode/electrolyte interface for lithium batteries using in situ synchrotron X-ray reflectometry—A new experimental technique for LiCoO2 model electrode

A new experimental technique was developed for detecting structure changes at electrode/electrolyte interface of lithium cell using X-ray reflectometry and two-dimensional model electrodes with a restricted lattice-plane. The electrodes were constructed with an epitaxial film of LiCoO₂ synthesized by pulsed laser deposition method. The orientation of the epitaxial film depends on the substrate plane; the 2D layer of LiCoO₂ is parallel to the SrTiO₃ (1 1 1) substrate (_(0 0 3)LiCoO₂//_(1 1 1)SrTiO₃)$({(003)}_{\text{LiCo}{\text{O}}_2}//{(111)}_{\text{SrTi}{\text{O}}_3})$, while the 2D layer is perpendicular to the SrTiO₃ (1 1 0) substrate (_(1 1 0)LiCoO₂//_(1 1 0)SrTiO₃)$({(110)}_{\text{LiCo}{\text{O}}_2}//{(110)}_{\text{SrTi}{\text{O}}_3})$. The anisotropic properties were confirmed by electrochemical measurements. Ex situ X-ray reflectivity measurements indicated that the impurity layer existed on the as-grown LiCoO₂ was dissolved and a new SEI layer with lower density was formed after soaking into the electrolyte. In situ X-ray reflectivity measurements indicated that the surface roughness of the intercalation (1 1 0) plane increased with applying voltages, while no significant changes in surface morphology were observed for the intercalation non-active (0 0 3) plane during the pristine stage of the charge–discharge process.     

Measuring method of three thermophysical parameters of solids by a thermal probe with instantaneous point contact: Discussion about applicability and measuring conditions

An instrument for the measuring method reported in the previous paper is a handy tester for three thermophysical parameters of solids in situ. Discussions about measurement errors caused by not strictly satisfying the measuring conditions, such as size and shape of the testing body, and about optimum initial temperature difference between thermal probe and testing body have been done. As a result of the experiment varying the shape of a probe end, it is shown that the radius of the contacting surface on a testing body has no influence on measuring thermophysical parameters. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(3): 202–211, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10085     

Comparison of the SiH4---C2H4 and SiH2Cl2---C2H4 systems during the synthesis of silicon carbide ultrafine particles by laser-induced gas-phase reaction

The synthesis conditions of SiC ultrafine particles from SiH₄ and C₂H₄ using a CO₂ laser were studied and a comparison was made between SiH₄---C₂H₄ and SiH₂Cl₂---C₂H₄ systems. Ultrafine SiC particles were synthesized by irradiating a SiH₄ and C₂H₄ gas mixture with a CO₂ laser at atmospheric pressure. SiC particles were obtained at a laser power of more than 0·92 kW/cm².

The behavior of the reaction flame temperature and the extent of the laser light absorption by SiH₄---C₂H₄ was different from that of SiH₂Cl₂---C₂H₄, although an abrupt temperature increase was observed in both cases. In the case of SiH₄---C₂H₄ an abrupt increase in the laser light absorption was not observed, whilst it was observed in the case of SiH₂Cl₂---C₂H₄. This difference resulted from the difference in liability to form solid carbon particles.