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The hydrogen desorption and absorption reactions of the complex metal hydride NaAlH4 are disproportionation processes, and the kinetics can be improved by adding a few mol% of Ti compounds, although the catalytic mechanism, including the location and state of Ti, remains unknown. In this study, we aimed to reveal the generating mechanism of catalytic Al–Ti alloy in NaAlH4 with TiCl3 using quantum multiprobe techniques such as neutron diffraction (ND), synchrotron X-ray diffraction (XRD), anomalous X-ray scattering (AXS), and X-ray absorption fine structure (XAFS). Rietveld refinements of the ND and XRD, profiles before the first desorption of NaAlD(H)4–0.02TiCl3 showed that Al in NaAlD(H)4 was partially substituted by Ti. On the other hand, Ti was not present in NaAlH4, and Al–Ti nanoparticles were detected in the XRD profile after the first re-absorption. This was consistent with the AXS and XAFS results. It is suggested that the substitution promotes the formation of a highly dispersed nanosized Al–Ti alloy during the first desorption process and that the effectiveness of TiCl3 as an additive can be attributed to the dispersion of Ti.

A method to obtain the quantitative lithium distribution of a lithium-ion battery cathode using laser-induced breakdown spectroscopy (LIBS) measurements is proposed. We perform LIBS measurements in a reduced argon atmosphere of 1000 Pa and use a calibration curve obtained by measuring the emission intensities at 610.4 nm of standard samples, whose atomic ratios of lithium to cobalt are 0, 0.10, 0.30, 0.51, 0.62, 0.80, and 0.99. The lithium distributions of cycled cathodes, which contain LiCoO2 as an active material, obtained by this method are relatively consistent with the Co(III) distributions obtained by X-ray absorption spectroscopy (XAS). XAS is the conventional method to quantitatively display the reaction distribution of a cathode material used in a lithium-ion battery. Additionally, LIBS can detect the precipitating decomposition products of the electrolyte, LiF, on the cathode. However, the precision of the lithium ratio using LIBS is not as good as that achieved for the Co(III) ratio obtained using XAS. Therefore, LIBS is suitable to obtain a semi-quantitative lithium distribution in a cathode of a lithium-ion battery through a much simpler procedure than XAS. Furthermore, LIBS has an advantage to detect the decomposition product of the electrolyte using laboratory-scale measurements.

Biomass yields and biofuel production were examined in a dual (solid and liquid)-phase cultivation system (DuPHA) with the unique filamentous cyanobacteria, Pseudanabaena sp. ABRG 5-3 and Limnothrix sp. SK1-2-1. Continuous circular cultivation was driven under the indoor closed (IC) or indoor opened (IO) conditions and provided biomass yields of approximately 8–27 g dry cell weight (DCW) floor m−2 d−1. Alkanes of heptadecane (C17H36) or pentadecane (C15H32) as liquid biofuels were also recovered from the lower liquid-phase, in which cyanobacteria were dropped from the upper solid-phase and continuously cultivated with a small amount of medium. After the main cultivation in DuPHA, the upper solid-phase of a cotton cloth on which cyanobacteria grew was dried and directly subjected to a combustion test. This resulted in the thermal power (kJ s−1) of the cloth with microalgae increasing approximately 20–50% higher than that of the cloth only, suggesting a possibility of using the solid phase with microalgae as solid biofuel.

In the present study, a novel system for the hypoxic culture of individual tissues was established for the subculturing of cell lines for research as well as for clinical culture of primary cells. To provide a hypoxic environment throughout the process of tissue handling and culture, we designed a clean bench with CO2 gas circulation and a hypoxic culture incubator containing disposable capsules. The bench top was covered with an acrylic chamber, and an atmosphere of 5.0% CO2-air was maintained using a sensor control. The cleanliness class of the chamber could easily be improved to 1 within 5 min of circulative filtration, even though it was found to be 105 before the unit was operated. Gas buffer solution (220 ml of 20 mM HEPES, 25 mM NaHCO3, pH 7.4) placed in a 500-ml plastic capsule in the unit stabilized the culture environment by functioning as a heat storage and gas pool. The inflow of air that occurred by the cap of the capsule was opened was excluded by the infusion of purging gas (5.0% CO2 and 95% N2); the O2 level returned to 2.0% within 4 min, after which the gas supply automatically switched to the culture gas (2.0% O2, 5.0% CO2, and 93% N2). If this purging process was omitted, restoration of the O2 level required 120 min, even though the inner volume was only 280 ml.