Pulverization mechanism of hydrogen storage alloys on microscale packing structure

In-situ and transient visualizations of the packing structure of a hydrogen storage alloy bed are carried out using an X-ray computed tomography (CT) system. The packing structure is clearly observed on the microscale using the CT system. When the alloy bed is subjected to hydrogen absorption–desorption cycles, the pulverization progresses from the lower to the upper regions of the bed. After several hydrogen absorption–desorption cycles, the packing structure in the lower region of the bed changes and the microstructural void decreases slightly. Based on these results, we propose a pulverization mechanism of the packed bed in which the friction between particles affects the pulverization process.     

Impact of Dynamic Interlayer Interactions on Thermal Conductivity of Ca3Co4O9

The phonon thermal conductivity of misfit-layered Ca₃Co₄O₉ has been calculated by perturbed molecular dynamics using a classical force field. Detailed numerical analyses reveal that, in spite of its smaller cross-sectional area, the CoO₂ layer transports more heat than the thicker rock salt (RS) layer, although its local thermal conduction is more suppressed than in another layered cobaltite, Na _x CoO₂. The origins of these differences have been elucidated through careful examination of the atomic arrangements in each layer. Since thermal conduction in the RS layer can be reduced without deteriorating electronic properties for which the CoO₂ layer is responsible, it is suggested that the RS layer should be modified to further suppress the overall in-plane thermal conductivity. Computational experiments with increasing number of Ca–O planes in the RS layer showed the opposite trend to what can be predicted based on the misfit between two dissimilar layers. Further analyses to reveal the origin of these unexpected results provide yet another strategy to further decrease the thermal conductivity, namely to control the dynamic interference between atoms across the interface between two layers.     

Effects of supercritical carbon dioxide treatment on the morphology of poly(l‐lactide)

Synthetic l ‐lactide random copolymers can be employed as controlled release materials when prepared using supercritical carbon dioxide (scCO₂), since they are biodegradable via hydrolysis. To determine the effects of thermal properties on polymer performance following scCO₂ processing, three types of poly(l ‐lactide) having different properties were assessed. The T_m of one poly(l ‐lactide) sample (H‐100) was found to be approximately 170 °C over the processing pressure range from 8 to 18 MPa, while a second sample (H‐440) also showed a constant value of approximately 152 °C. In contrast, the poly(l ‐lactide) REVODE exhibited a T_m of 146 °C prior to processing but a higher value of 147 °C following treatment at 8 MPa. Unlike the H‐100 and H‐440, the T_m value of the REVODE tended to decrease with increasing pressure. The T_g values increased greatly under mild conditions of 8 MPa pressure and a temperature of 40 °C. In particular, the T_g values for the H‐440 and REVODE increased by 4 °C and 5 °C, respectively. All T_g values were lowest at 12 MPa and increased with increasing processing pressure, although the effect of processing temperature was minimal. The Χ_{c DSC} of the H‐100 was 18% initially but increased to 20% upon scCO₂ processing at 40 °C and 14 MPa, and showed further increases at higher processing temperatures. Although the relationship between processing temperature and Χ_{c DSC} values for the H‐440 showed the same trend as observed with the H‐100, a different trend was seen for the REVODE. The Χ_{c XRD} values obtained from the XRD analyses differed from the values generated by DSC analysis, and showed a maximum degree of crystallinity following processing at 80 °C both with and without scCO₂ treatment. ATR FT‐IR analyses identified peaks due to semicrystalline regions in poly(l ‐lactide) samples treated with scCO₂, even when applying low temperatures. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44006.     

Detection of light-absorbing iron oxide particles using a modified single-particle soot photometer

Copyright © 2016 American Association for Aerosol Research     

Inactivation of Bacillus spores by the combination of moderate heat and low hydrostatic pressure in ketchup and potage

The combination effect of moderate heat and low hydrostatic pressure (MHP) on the reduction of Bacillus subtilis, Bacillus coagulans and Geobacillus stearothermophilus spores in food materials (potage and ketchup) was investigated. These bacterial spores were suspended in potage (pH 7), acidified potage (pH 4), neutralized ketchup (pH 7) and ketchup (pH 4). The suspensions were treated with and without pressure (100 MPa) and temperatures of 65-85 degrees C for 3 to 12 h. The bacterial spores were inactivated by 4-8 log cycles during MHP treatment in potage, acidified potage and ketchup, whereas the spores were highly resistant to long time heat treatment in potage and neutralized ketchup. The degrees of spore destruction were mostly dependent on pH and medium composition during MHP treatment. The inactivation effect in MHP treatment was higher at the pH 7 than at pH 4 both in ketchup and potage. The bacterial spores showed higher inactivation in potage than ketchup during MHP treatment.     

Organofunctionalized catalyst surfaces highly active and selective for carbon–carbon bond-forming reactions

This article illustrates two types of organofunctionalized heterogeneous catalysts for variety of organic carbon–carbon bond-forming reactions, summarizing our previous reports and also presenting new data. Organic amines with an alkoxysilane moiety were immobilized on inorganic silica-alumina surfaces (SA-NR₂) by simple silane-coupling reactions between the silica-alumina surface (SA) and the alkoxysilane. This SA-NR₂ acted as acid–base bifunctional heterogeneous catalysts for carbon–carbon bond-forming reactions, such as cyano-ethoxycarbonylation, Michael reaction of nitriles, and nitro-aldol reaction. These reactions did not occur with either SA or homogeneous amine compounds. In addition, the mixture of SA and homogeneous amine showed low catalytic activity due to undesirable acid–base neutralization reaction. Achiral organic silane-coupling reagents with a variety of functional groups were also immobilized on a SiO₂ surface that had been immobilized with chiral bis(oxazoline) (BOX), to which Cu ions were coordinated to make chiral Cu–BOX complexes on the SiO₂ surface. The SiO₂-supported Cu–BOX complex catalyst functionalized with achiral 3-methacryloxypropyltrimethoxysilane dramatically increased enantioselectivity in the asymmetric Diels–Alder reaction of cyclopentadiene and 3-acryloyl-2-oxazolidinone. The organofunctionalized catalysts showed much better performances for the C–C bond-forming reactions compared to the corresponding homogeneous systems. The heterogeneous catalysts thus obtained were characterized by solid-state ¹³C and ²⁹Si MAS NMR, FT-IR, UV/vis, XAFS, ESR, XRF, and elemental analysis.     

Denatured-jacalin derivatives with selective recognition for O-linked glycosides (ST,T, Tn,and STn Type) on IgA1 hinge region

Immunoglobulin A1 (IgA1) concentration in the plasma of patients with IgA nephropathy (IgAN) as the cause of renal failure is higher than that in the plasma of normal controls. IgA1 with abnormal sugars is considered to deposit in the glomerular mesangium, aggravating nephritis in IgAN. Jacalin is a lectin that recognizes sugars on IgA1. However, its selective-recognition for normal-type (ST type, NeuAc-α(2,3)-Gal-β(1,3)-GalNAc) and abnormal-type (T type, Gal-β(1,3)-GalNAc; Tn type, GalNAc; STn type, NeuAc-α(2,6)-GalNAc) sugars α-O-linked to serine/threonine in IgA1 is weak. Therefore, jacalin cannot be used for recognizing specific sugar types on IgA1. We attempted to develop a new recognition method for specific sugar types on IgA1 by utilizing the multirecognition capability of jacalin. Its binding abilities were regulated by heat denaturation with suitable template sugar (galactose or N-acetylgalactosamine). Further, we successfully prepared denatured-jacalin derivatives, which recognized ST-/T-type sugars on IgA1, by sugar-immobilized affinity chromatography. Enzyme-linked immunosorbent assay of denatured-jacalin derivatives, showed the ratios of abnormal sugars on IgA1 in the plasma of IgAN patients and normal controls to be approximately 60% and 20%, respectively. The results proved that profiling of sugar types in IgAN can successfully be performed by solely using jacalin derivatives.     

Antifungal activity of the fermentation product of herbs by lactic acid bacteria against tinea

The fermentation product of herbs by lactic acid bacteria (FHL), in which Enterococcus faecalis TH10 predominated, was assayed for antifungal activity against tinea. The antifungal activity of FHL was as high as that of a synthetic fungicide. Autoclaving FHL did not reduce its antifungal activity, whereas neutralizing it did. The results suggested that nonproteinaceous compounds or organic acids in FHL could inhibit the growth of the dermatophyte tinea under low-pH conditions, and that malonic acid and acetic acid could have especially high antifungal activity against tinea.