In this study, the fatigue properties of additively manufactured titanium clasps were compared with those of commercially pure titanium (CPTi) and Ti-6Al-4V (Ti64), manufactured using laser powder-bed fusion. Methods: Fourteen specimens of each material were tested under the cyclic condition at 1 Hz with applied maximum strokes ranging from 0.2 to 0.5 mm, using a small stroke fatigue testing machine. A numerical approach using finite element analysis (FEA) was also developed to predict the fatigue life of the clasps. Results: The results showed that although no significant differences were observed between the two materials when a stroke larger than 0.35 mm was applied, CPTi had a better fatigue life under a stroke smaller than 0.33 mm. The distributions of the maximum principal stress in the FEA and the fractured position in the experiment were in good agreement. Conclusions: Using a design of the clasp of the present study, the advantage of the CPTi clasp in its fatigue life under a stroke smaller than 0.33 mm was revealed experimentally. Furthermore, the numerical approach using FEA employing calibrated parameters for the Smith-Watson-Topper method are presented. Under the limitations of the aforementioned clasp design, the establishment of a numerical method enabled us to predict the fatigue life and ensure the quality of the design phase before manufacturing.

In order to solve the problems of global warming and depletion of energy resource, renewable energy systems such as wind generation are getting attention. However, wind power fluctuates due to variation of wind speed, and it is difficult to perfectly forecast wind power. This paper describes a method to use power forecast data of wind turbine generators considering wind power forecast error for optimal operation. The purpose in this paper is to smooth the output power fluctuation of a wind farm and to obtain more beneficial electrical power for selling.

A novel α,β-unsaturated iminium salt (3) incorporated into a rigid dibenzobarrelene backbone was synthesized by heating N-(anthracen-9-ylmethyl)-2,6-diisopropylaniline (2) and 3-phenyl-2-propynal in THF in the presence of excess amounts of magnesium sulfate and 0.5 equivalents of an HBF4-Et2O complex. The molecular structure of 3 was characterized unambiguously by NMR spectroscopy and single-crystal X-ray diffraction (SCXRD) analyses. Compound 3 exhibits yellow luminescence in CH2Cl2 (λem = 516 nm) and in the solid state (λem = 517 nm) with relatively high to moderate quantum yields (ΦF(CH2Cl2) = 0.63; ΦF(solid) = 0.34).

Recently, miniaturizing electronic devices, such as handy phone, have been strongly requested. Number of mounted electronic components has been abruptly increased. Therefore, the high density of the component is mounted, the need for heat dissipation is increased. A heat radiation substrate is one of the most promising candidates to suppress increasing temperature of electronic devices. The heat radiation substrates need both high thermal conductivity and low coefficient of thermal expansion. A semiconductor has low coefficient of thermal expansion. A copper-molybdenum alloy has both high thermal conductivity and low coefficient of thermal expansion. An electroplated Cu-Mo alloy film has been investigated. However, deposition rate was decreased with high molybdenum content in the alloy. High molybdenum content is necessary to obtain low coefficient of thermal expansion. The low deposition rate is serious issue to put into industrial usage. The purpose of this study is to produce a film with high molybdenum content by high deposition rate. The chemicals used in bath preparation were CuSO4・5H2O 0.13 mol/L, Na2MoO4・2H2O 0.53 mol/L, C6H5Na3O7・2H2O 0.91 mol/L. The bath was adjusted to pH 9.0 and then electroplated. Nickel plate is used as the substrate and platinum plate is used as the anode. In this study, both bath temperature and current density have been investigated. Higher bath temperature makes deposition rate lower as shown in Fig.1. Higher current density makes deposition rate higher, but the current density dependence of the deposition rate is different on the bath temperature as shown in Fig.2. Lower dependence is observed in the case of higher bath temperature and effect of bath temperature on molybdenum content is different in the case of each current density. In the case of high current density, the molybdenum content increased with increasing bath temperature as shown in Fig.3. Therefore, when both bath temperature and current density are high, the films with high molybdenum content are plated by relatively high deposition rate as shown in Fig.4. The three micrometers thick copper-molybdenum alloy film with 23.9 at% molybdenum content film are plated for 1 hour under the condition of 50℃ bath temperature and 10 mA/cm2 current density. This deposition time to obtain 3 micrometers is one twentieth to obtain previously studied film with 17.9 at% molybdenum content. Figure 1

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