Low-Cost Bipolar Plates of Ti4O7-Coated Ti for Water Electrolysis with Polymer Electrolyte Membranes.

Although hydrogen is expected to play an important role in the storage of energy from renewable energy sources, technology to produce hydrogen at low cost is needed for its widespread use. The key to the low-cost production of hydrogen with a polymer electrolyte membrane (PEM) water electrolysis system, which is widely used today, is to replace the Au- or Pt-coated Ti with a low-cost material that can be manufactured from inexpensive, corrosion-resistant, and conductive components. We studied titanium suboxide (Ti4O7)-coated titanium (Ti) bipolar plates, which can be substituted for commonly used Pt-coated Ti bipolar plates, as an inexpensive way of producing the PEM water electrolysis system. The water electrolysis characteristics of the cell were evaluated using Ti4O7-sputtered Ti for the bipolar plates of the water electrolysis cell, and the applicability of Ti4O7-sputtered Ti was investigated. The Ti4O7-sputtered Ti had a very low contact resistance (4-5 mΩ cm2) before and after voltage application that was equivalent to that of gold or platinum plating. The efficiency of water electrolysis in this study was comparable to those of previous reports using bipolar plates coated with precious metals. This development opens the door for fabrication of low-cost electrolyzers as well as related electrochemical devices such as fuel cells, sensors, catalysts, and air or liquid cleaning devices.

Simple and scalable preparation of master mold for nanoimprint lithography.

Nanoimprint lithography (NIL) is one of the most prominent bottom-up techniques for duplicating nanostructures with a high throughput. However, fabrication of starting master mold commonly requires expensive equipment of top-down techniques, or additional steps to transfer the fabricated patterns from bottom-up methods. Here we demonstrate that a SiO2 nanostructure manufactured from a self-assembled block copolymer, polystyrene-b-polydimethylsiloxane (PS-b-PDMS), directly serves as a master mold for NIL without further modification. A hexagonally aligned pattern over the entire substrate is established using a simple technique; solvent annealing and etching. Etching also plays an important role in endowing fluorine on the surface of SiO2, thus promoting smooth demolding upon imprinting. The obtained pattern of the SiO2 nanostructure is transferred to a polymer surface using UV nanoimprint. Identical patterns of the SiO2 nanostructure are elaborately reproduced on Ni and Cu nanodot arrays via electroplating on the polymer transcript, which was verified by morphological observations. The uniformity of the replicated Ni nanodot array is evaluated using spectroscopic ellipsometry. The measured optical response of the Ni nanodot is validated by electromagnetically simulated results, indicating that the pattern transfer is not limited to a small local area. In addition, the durability of the SiO2 mold pattern is corroborated after the imprinting process, thus guaranteeing the reusability of the fabricated nanostructure as a master mold. The proposed approach does not require any high-end lithographic techniques; this may result in significant cost and time reductions in future nanofabrication.

Three-Dimensional Periodically Ordered Nanohetero Metallic Materials from Self-Assembled Block Copolymer Composites.

We report a synthetic route to inorganic nanoheterostructures with tunable size and morphology via self-assembled block copolymer mesophase templates. Two Fe precursors, tricarbonyl(cyclooctatetraene) iron and acetylacetonate iron(III), and one Pt precursor, platinum dimethylcyclooctadiene, were selectively introduced into separate polymer blocks of a block copolymer, polystyrene-b-poly-4-vinylpyridine, and then the block copolymer templates were removed by pyrolysis. Self-assembled inorganic nanoheterostructures (spheres, hexagonal cylinders, and layers of hard magnetic phase FePt in a matrix of soft magnetic phase α-Fe) were produced. The morphology and domain size of the nanoheterostructures could be tailored by controlling the molecular weight and relative block lengths of the block copolymers. The controlled size and morphology of the inorganic nanoheterostructures demonstrate the method's utility for producing highly functional materials.

Theoretical analysis of concerted and stepwise mechanisms of Diels-Alder reactions of butadiene with silaethylene and disilene.

The concerted and the stepwise mechanisms of the Diels-Alder reactions of butadiene with silaethylene and disilene were studied by ab initio MO methods. For the reaction of butadiene and silaethylene, an asymmetric concerted process that is almost stepwise and two stepwise processes were located. For the first step of the stepwise process, the C-Si bond formation is more favorable than the C-C bond formation. The activation energy barrier of the concerted transition state is only 0.89 kcal/mol lower than that of the first-step transition state of the C-Si bond formation for the stepwise process by the CASPT2 calculation level. For the reaction of butadiene and disilene, the activation energy barrier of the concerted-type transition state constrained with Cs symmetry is about 9 kcal/mol higher than that of the stepwise transition state by the CASSCF method. The energy barrier of the first step of the stepwise reaction disappears at the CASPT2/6-311++G(d,p) calculation level including the nondynamical correlation energy, although the reaction of the butadiene with disilene occurs through the stepwise-like process.

Development of the sport achievement orientation questionnaire for Japanese athletes by exploratory factor analysis.

In this study, a questionnaire to assess achievement orientation in sport for Japanese athletes was developed. We created the questionnaire by picking items from free descriptions of Japanese athletes and using factor analysis of the responses in a Japanese sport setting. The subjects were 2,415 athletes (M=16.7 yr., SD=2.7) in Japan. Factor analyses in this study identified three factors. Top Level Orientation, Demonstrating Ability Orientation, and Win Orientation, respectively. An examination of the intercorrelations among the three scores showed the subscales were related. There were no correlations between the new measure and the Japanese versions of the Sport Orientation Questionnaire and the Task and Ego Orientation in Sport Questionnaire except that the correlation of Win Orientation and the SOQ Athletic Success Orientation was low and negative. These results suggested that the three subscales appeared to be separate but related factors, and that it is an original measurement for only Japanese athletes. The overall factor reliability and validity based on the sample suggested that the Sport Achievement Orientation Questionnaire for Japanese Athletes can be valuable means for the investigation of achievement orientation in Japanese sport and exercise settings.

Exploratory factor analysis of the Sport Orientation Questionnaire and the Task and Ego Orientation in Sport Questionnaire in a Japanese sport setting.

This study examined sport achievement orientation within the japanese sport setting. 1,836 male and 425 female athletes (M age = 18.6 yr.) from 47 sports completed the Japanese version of the Sport Orientation Questionnaire (24 items), and 1,781 males and 421 females (M age = 18.6 yr.) from 47 sports completed that of the Task and Ego Orientation in Sport Questionnaire (14 items). While the original English versions of the questionnaires are composed of three and two factors, respectively, present exploratory factor analyses identified four factors in the Sport Orientation Questionnaire and three in the Task and Ego Orientation in Sport Questionnaire. In this study, two types of the SOQ Competitiveness and the TEOSQ Ego Orientation emerged even though the original versions included only one type. A one-way analysis of variance indicated that sex differences were significant for all subscales. Sex differences in the Sport Orientation Questionnaire of Japanese resembled those of Americans. The overall factor reliability and validity based on the sample suggested that the modified Japanese versions of the two questionnaires can be valuable in the investigation of sport achievement orientation in Japanese sport and exercise settings.