The role of the solder joint as an elastic foundation is investigated first for structural analysis of the pin. Failure mechanisms are discussed. For various pin cross sections, guidelines for computing the foundation constant by analytical and finite element methods are established. Exact expression are derived for the pin stress. The solder stress (radial pressure or tension) is found by an approximate contact analysis. Elasto-plastic pin analysis, for excessive thermal mismatch, is effected by an iterative method. The variation of the plastic domain is examined for various size and material parameters. Axial forces in the presence and absence of pin plasticity are investigated, and the overall effect on the PGA is discussed.

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In this study, we investigate Cu2O film electrically connected with TiO2 film, as a p-n type heterojunction, for enhancing the photoelectrocatalytic (PEC) activity towards degradation of methyl orange (MO) solution under ultraviolet irradiation. By using a versatile magnetron sputtering technique, the Cu2O films were deposited onto three different substrates, i.e., ITO, Ni/Cr and Pt, denoted as Cu2O/It, Cu2O/Ni and Cu2O/Pt, respectively, whereas the TiO2 film was deposited on ITO substrate. All three Cu2O films show about the same characteristics of preferential (111) plane of the Cu2O oxide. While electrically coupled with TiO2, the Cu2O/Pt exhibits the highest PEC activity on MO degradation among four different couples. Thus, the increase in PEC activity of the Cu2O/Pt-TiO2 is due to both the electron affinity of the Pt substrate and the effect of the equilibration of Fermi level of which is more compatible for Cu2O and TiO2 oxides, decreasing the electrochemical capacitances of the p-n heterojunction. The electric-assisted heterojunction offers an efficient way for photogenerated electron transport from TiO2 to holes in the Cu2O, rendering enhanced PEC activity.

A cost-effective multimedia learning system, RICEM, for reciprocating internal combustion engines was proposed in this study. This system contained the graphical introduction of engine components, engine structure animation, thermal theory, feedback and assessment based on Mayer’s multimedia learning cognitive theory. Reciprocating internal combustion engines are used all over the world to drive compressors, pumps, electric generators, motor ships and other equipments. We used multimedia software to construct the learning system. An experiment comprising of two groups of 30 participants separately was conduct to test the effectiveness and showed that there was a significant difference between the pre-test and post-test score in the RICEM group, as compared with the control group. This study suggested that a collaborative application appeared to be promising in supporting effective learning of modern technology, by combining the integration of learning theory and multimedia design.

Three types of visible-light enabled titanium oxide (TiO2) films deposited on indium tin oxide (ITO) substrates at different levels of doping nitrogen (N) and carbon (C) and sputtering power are investigated for their capabilities to both pollution control and splitting water on hydrogen production. All samples are similar in morphological and microstructural features, but differ in their interfacial phase and dopants. For the N,C-codoped TiO2 film prepared at a higher sputtering power, tin ions can permeate into the growing TiO2 film from the ITO substrate and promote the formation of crystalline Ti1-xSnxO2 layer. It shows the highest photocatalytic oxidation rate over methylene blue (MB) solution under ultraviolet and blue light irradiation, respectively. This is ascribed to the photosensitized carbon on the columnar grains, leading an increase in the MB adsorption capacity and light harvesting efficiency. Conversely, the N-TiO2 film prepared at a lower power exhibits the highest photocurrent density and hydrogen yield rate of which a higher Schottky barrier formed at the TiO2/ITO interface. This suggests that the interfacial properties of TiO2/ITO film and C-doping truly control its photocatalytic capabilities in addition to the well-known surface states.