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Ni alloys are examined as redox-resistant alternatives to pure Ni for solid oxide fuel cell (SOFC) anodes. Among the various candidate alloys, Ni–Co alloys are selected due to their thermochemical stability in the SOFC anode environment. Ni–Co alloy cermet anodes are prepared by ammonia co-precipitation, and their electrochemical performance and microstructure are evaluated. Ni–Co alloy anodes exhibit high durability against redox cycling, whilst the current-voltage characteristics are comparable to those of pure Ni cermet anodes. Microstructural observation reveals that cobalt-rich oxide layers on the outer surface of the Ni–Co alloy particles protect against further oxidation within the Ni alloy. In long-term durability tests using highly humidified hydrogen gas, the use of a Ni–Co cermet with Gd-doped CeO 2 suppresses degradation of the power generation performance. It is concluded that Ni–Co alloy cermet anodes are highly attractive for the development of robust SOFCs. • Ni–Co alloy cermet anodes for solid oxide fuel cells were developed. • Durability up to 50 redox cycles was improved by alloying Ni with Co. • 1000-h durability using highly-humidified hydrogen fuel was verified. • Ni–Co alloy is a robust anode material even in 80%-humidified hydrogen fuels. [ABSTRACT FROM AUTHOR]

It was reported that wax matrix (WM) particles composed of low-melting-point microcrystalline wax showed unique release behaviors; the particles released only a small amount of the entrapped drug (non–diffusion-controlled release) at 37°C, whereas it showed comparatively fast drug release in a diffusion-controlled manner at 25°C. However, the mechanism of the drug release is still unclear. The objective of this study was to determine the mechanism of drug release from the WM particles using X-ray computed tomography. In the WM particles collected during dissolution tests at 25°C, the void space derived from drug release increased with increasing time, and there was no change in the structure, indicating that the WM particles released drug while maintaining the particle shape at 25°C. In the WM particles collected during dissolution tests at 37°C, the void space was confirmed at initial time point; however, at subsequent time points, the void space was disappeared, and the roughness of the surface was evident. This structural change may have blocked the conveyance pathway of the outer medium, which would inhibit the drug release. The difference between the drug-release mechanisms of the WM particles at the 2 temperatures will be valuable for developing cooling-triggered, temperature-sensitive formulations. [ABSTRACT FROM AUTHOR]

Low-melting-point substances are widely used to develop temperature-sensitive formulations. In this study, we focused on microcrystalline wax (MCW) as a low-melting-point substance. We evaluated the drug release behavior of wax matrix (WM) particles using various MCW under various temperature conditions. WM particles containing acetaminophen were prepared using a spray congealing technique. In the dissolution test at 37 °C, WM particles containing low-melting-point MCWs whose melting was starting at approx. 40 °C (Hi-Mic-1045 or 1070) released the drug initially followed by the release of only a small amount. On the other hand, in the dissolution test at 20 and 25 °C for WM particles containing Hi-Mic-1045 and at 20, 25, and 30 °C for that containing Hi-Mic-1070, both WM particles showed faster drug release than at 37 °C. The characteristic drug release suppression of WM particles containing low-melting-point MCWs at 37 °C was thought attributable to MCW melting, as evidenced by differential scanning calorimetry analysis and powder X-ray diffraction analysis. Taken together, low-melting-point MCWs may be applicable to develop implantable temperature-sensitive formulations that drug release is accelerated by cooling at administered site. [ABSTRACT FROM AUTHOR]

Abstract: Snowpack samples were collected from a snow pit sequence (6 m in depth) at the Murodo-Daira site near the summit of Mt. Tateyama, central Japan, an outflow region of Asian dusts. The snow samples were analyzed for a homologous series of low molecular weight normal (C1–C10) and branched (iC4–iC6) monocarboxylic acids as well as aromatic (benzoic) and hydroxy (glycolic and lactic) acids, together with major inorganic ions and dissolved organic carbon (DOC). The molecular distributions of organic acids were characterized by a predominance of acetic (range 7.8–76.4 ng g−1-snow, av. 34.8 ng g−1) or formic acid (2.6–48.1 ng g−1, 27.7 ng g−1), followed by propionic acid (0.6–5.2 ng g−1, 2.8 ng g−1). Concentrations of normal organic acids generally decreased with an increase in carbon chain length, although nonanoic acid (C9) showed a maximum in the range of C5–C10. Higher concentrations were found in the snowpack samples containing dust layer. Benzoic acid (0.18–4.1 ng g−1, 1.4 ng g−1) showed positive correlation with nitrate (r = 0.70), sulfate (0.67), Na+ (0.78), Ca2+ (0.86) and Mg+ (0.75), suggesting that this aromatic acid is involved with anthropogenic sources and Asian dusts. Higher concentrations of Ca2+ and SO4 2− were found in the dusty snow samples. We found a weak positive correlation (r = 0.43) between formic acid and Ca2+, suggesting that gaseous formic acid may react with Asian dusts in the atmosphere during long-range transport. However, acetic acid did not show any positive correlations with major inorganic ions. Hydroxyacids (0.03–5.7 ng g−1, 1.5 ng g−1) were more abundant in the granular and dusty snow. Total monocarboxylic acids (16–130 ng g−1, 74 ng g−1) were found to account for 1–6% of DOC (270–1500 ng g−1, 630 ng g−1) in the snow samples. [Copyright &y& Elsevier]

Abstract: Pheopigments such as pheophytin a, pyropheophytin a and steryl chlorin esters are abundant chlorophyll transformation products in many oceanic and lacustrine sedimentary environments. They have been widely used as direct indicators of phytoplankton and zooplankton activity in aquatic environments. In this study, we evaluate the sources and transformation processes of pheopigments in a sediment core from Lake Haruna (Japan), based on stable carbon (δ13C) and hydrogen (δD) isotopic composition of phytol and sterols as side chains of pheopigments. The isotopic compositions of phytol from sedimentary pheophytin a (δ13C=−29.2‰ to −27.6‰, δD=−388‰ to −376‰) and some sterols from steryl chlorin esters (e.g. 24-methycholesta-5,22-dien-3β-ol; δ13C=−29.4‰ to −27.9‰, δD=−340‰ to −325‰) are close to those of phytol (δ13C=−31.7‰ to −27.0‰, δD=−385‰ to −371‰) and corresponding sterols (e.g. 24-methycholesta-5,22-dien-3β-ol; δ13C=−28.4‰ to −28.1‰, δD=−335‰ to −320‰) from modern phytoplankton. The isotopic signatures are consistent with an origin exclusively from aquatic organisms. In contrast, the isotopic compositions of phytol from pyropheophytin a (δ13C=−31.7‰ to −29.1‰, δD=−379‰ to −341‰) and other sterols from steryl chlorin esters (e.g. 24-ethylcholest-5-en-3β-ol; δ13C=−33.2‰ to −30.2‰, δD=−298‰ to −270‰) vary throughout the core, with values ranging between those from modern phytoplankton (e.g. 24-ethylcholest-5-en-3β-ol; δ13C=−28.7‰ to −28.1‰, δD=−348‰ to −345‰) and terrestrial C3 higher plants (δ13C=−41.5‰ to −31.7‰, δD=−352‰ to −295‰ for phytol; δ13C=−38.6‰ to −28.0‰, δD=−283‰ to −225‰ for 24-ethylcholest-5-en-3β-ol). These results suggest that terrestrially derived phytol and sterols potentially contribute to the side chain of pyropheophytin a and steryl chlorin esters, respectively. [Copyright &y& Elsevier]

Abstract: We determined hydrogen, carbon and nitrogen isotopic compositions of chlorophylls a and b isolated from leaves of five C3 higher plant species (Benthamidia japonica, Prunus japonica, Acer carpinifolium, Acer argutum and Querus mongloica), and hydrogen and carbon isotopic compositions of phytol and chlorophyllides in the chlorophylls to understand isotopic fractionations associated with chlorophyll biosynthesis in these species. Chlorophylls are depleted in D relative to ambient water by ∼189‰ and enriched in 13C relative to bulk tissue by ∼1.6‰. These data can be explained by the contribution of isotopic fractionations during phytol and chlorophyllide biosyntheses. Phytol is more depleted in both D (by ∼308‰) and 13C (by ∼4.3‰), while chlorophyllides are less depleted in D (by ∼44‰) and enriched in 13C (by ∼4.8‰). Such inhomogeneous distribution of isotopes in chlorophylls suggests that (1) the phytol in chlorophylls reflects strong D- and 13C-depletions due to the isotopic fractionations during the methylerythritol phosphate pathway followed by hydrogenation, and (2) the chlorophyllides reflect D- and 13C-enrichments in tricarboxylic acid cycle. On the other hand, chlorophylls are slightly (∼1.2‰) depleted in 15N relative to the bulk tissue, indicating that net isotopic fractionation of nitrogen during chlorophyll biosynthesis is small compared with those of hydrogen and carbon. [Copyright &y& Elsevier]

• Ultra-thin glass (UTG) with its enhanced quality via CO 2 laser fusion cutting. • A new parameter on the assisting air was crucial in edge shape control. • Residual thermal stress was reduced by applying an additional laser beam. • The maximum flexural strength reached ∼ 500 MPa while the large data variation. • Spatter deposition control will be a key to improving flexural strength. The authors demonstrated the cutting of ultra-thin glass (UTG) with a thickness of 100 μm using a laser fusion cutting approach, which showed significant potential for drastically improving flexural strength. The authors proposed a novel control method for optimizing the edge shape to avoid previously reported drooping. Additionally, the authors presented guidelines for reducing the residual stress on the glass edge using two laser-superposed spots, resulting in a reduction in the retardation value by ∼ 43 %. The two-point bending test indicated that the maximum strength exceeded 500 MPa, whereas the minimum strength was approximately 100 MPa, which was likely caused by spatter deposition. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the nucleation behavior in the electroless displacement deposition of metal particles (Pt, Rh, Pd, Cu, Ag, and Au) onto n-Si wafers from a metal-salt solution containing HF. The particle density of metals varies widely from 106 (Pt) to 1011 (Au) cm−2, depending on the kind of metal. Deposited metals can be classified into two types of nucleation behavior. One consists of the platinum group elements, including Pt, Rh, and Pd, which display lower particle densities than elements of the other group and depend on the type of pretreatment of the n-Si wafer, and thus the surface conditions of Si. The second group consists of the copper group elements, including Cu, Ag, and Au, which display higher particle density than the first group and are independent of pretreatment. The size of deposited particles decreases from hundreds nm to tens nm as the particle density increases. Moreover, the displacement deposition of the Pt and Ag particles onto n-Si are in progressive and instantaneous nucleation modes, respectively. [Copyright &y& Elsevier]