High-throughput method for a kinetics analysis of the high-pressure inactivation of microorganisms using microplates

Using microplates as pressure and cultivation vessels, a high-throughput method was developed for analyzing the high-pressure inactivation kinetics of microorganisms. The loss of viability from a high-pressure treatment, measured based on the growth delay during microplate cultivation, showed reproducibility with the conventional agar plate method and was applicable for the kinetics analysis.     

Wear Resistance of SiO2-Doped Y-TZP Grinding Media During Wet Milling

Grinding media 1 mm in diameter, containing 0.4 and 0.7 wt% SiO₂, were fabricated using Y-TZP powder prepared by the liquid-phase method. The wear resistance of media for grinding, with and without the addition of BaTiO₃ powder, was evaluated at 20–80°C in water and in a nonaqueous solvent, isoparaffin. A rapid increase in the media wear rate of SiO₂-undoped media at 60°C was observed using water as a solvent, but little wear was observed for isoparaffin. The operating time until a rapid increase in the wear rate was observed in water increased with the increase in the grain size of the Y-TZP media. When the media wear became stable, the media surface was observed to be smooth. This suggested that the hydration reaction of Y₂O₃ and/or ZrO₂ by OH⁻ was inhibited by an increase in the grain size, and as a consequence, the decay of the grain boundaries was suppressed. In contrast, several traces of grain loss from the grain boundaries were confirmed on the worn surface of the media when a rapid increase in the wear rate was observed. The wear resistance for grinding BaTiO₃ powder using SiO₂-doped and -undoped media was also investigated. The wear for SiO₂-undoped media increased drastically with increasing slurry temperature; however, the wear for SiO₂-doped media did not increase, but was low and stable, regardless of the slurry temperature. This indicated that the hydration reaction of Y₂O₃ and/or ZrO₂ by OH⁻ was further inhibited by the segregation of SiO₂ at the grain boundaries, and hence SiO₂-doped Y-TZP media have high wear resistance, even with increased slurry temperature.     

Carbon Interlayer Between CVD SiC and SiO2 in High‐Temperature Passive Oxidation

The oxidation behavior of high‐purity silicon carbide (SiC) prepared by chemical vapor deposition was investigated by thermogravimetry, transmission electron microscopy, and Raman spectroscopy in the temperature range 1534–1902 K in pure O₂. The carbon layer formed at the SiC/SiO₂ interface upon oxidation above 1784 K. Raman peaks corresponding to D‐ and G‐bands could be identified from the carbon layer. Bubbles were observed in the SiO₂ scale after the oxidation at 1873 K. This could be attributed to the accumulation of CO gas at the SiC/SiO₂ interface, resulting in the formation of the carbon layer and bubbles. These suggest that the oxidation rate of SiC is limited by the outward diffusion of CO in the SiO₂ scale in this temperature range.     

Iridium‐Catalyzed Annulation of Aromatic Imines with 1,3‐Dienes via Direct Functionalization of an Aromatic C?H Bond

The [3+2] annulation of N‐sulfonyl aromatic imines with 1,3‐dienes proceeded via a direct C H functionalization to give 1‐aminoindane derivatives in high yields with high regio‐ and stereoselectivities. The iridium complex coordinated with a substrate 1,3‐diene displayed high catalytic activity. The reaction proceeds via the direct formation of the aryliridium(I) species from the aromatic aldimine and an iridium(I) acetate species via a concerted metalation‐deprotonation pathway.

     

Bonding Properties of Liquid Crystalline Epoxy Resins Having Different Phase Structures

Liquid-crystalline epoxy resin systems, which have different phase structures (isotropic and nematic polydomain), were prepared. The bonding properties of their systems were investigated and related to their phase structure. As a result, the lap shear strength of the nematic system was lower than that of the isotropic system, although the nematic adhesive layer showed larger deformability than the isotropic one. The interfacial bonding properties of both the isotropic and nematic systems were investigated, and, thus, it was clarified that the low bonding strength of the nematic system was due to the low concentration of hydroxyl groups at the adhesive interface. The decrease in the concentration of hydroxyl groups was due to the restriction of the molecular motion derived from the ordered structure of the nematic system.     

Material performance in a solvent extraction Liquefaction plant in Japan

Corrosion behaviour of various steels and alloys in the solvent extraction coal liquefaction process in Japan has been studied by the inplant testing in a 1 ton/ day plant and by the laboratory tests related to it. The severest corrosion was observed in the high pressure separator, corrosion thickness loss and pitting depth being the greatest and stress corrosion cracking being observed for 18–8 series austenitic stainless steels. The cause may be the occurrence of water condensate containing high Cl^? and H₂S. Otherwise corrosion was relatively mild. No obvious symptom of notorious organic-chloride corrosion reported in the U.S. has been observed.     

Inhibitory effects of antihypertensive drugs on mesangial cell proliferation after anti-thymocyte serum (ATS)-induced mesangiolysis in spontaneously hypertensive rats

The effects of antihypertensive drugs on mesangial cell proliferation were studied in spontaneously hypertensive rats (SHR) with anti-thymocyte serum (ATS)-induced glomerulo-nephritis. Rats were treated with either enalapril (Group 1), nifedipine (Group 2), or reserpine + hydrochlorothiazide + hydralazine (Group 3), or were untreated (Group 4). The animals were sacrificed 2, 4 and 7 days after ATS injection and the glomerular cell number and degree of mesangial area expansion were examined. A marked, similar decrease in glomerular nuclear cell number (NC) due to severe mesangiolysis was observed in all of the groups on day 2. Thereafter, an increase in NC reflecting mesangial cell proliferation after mesangiolysis occurred in Group 4 on days 4 and 7. In Group 1 and 2, the NC was significantly smaller than that in Group 4 on days 4 and 7, indicating suppression of mesangial cell proliferation. In Group 3, however, the number of NCs did not differ from that in Group 4 on days 4 and 7, indicating a lack of such suppression by conventional antihypertensive drugs. The degree of mesangial area expansion (MS) showed the same pattern as mesangial cell proliferation. That is, the rapid increases in MS seen in Group 4 on days 4 and 7 were apparently suppressed in Groups 1 and 2, but not in Group 3. Our in vivo observations that both an angiotensin converting enzyme (ACE) inhibitor and a calcium channel blocker suppress mesangial cell proliferation and mesangial area expansion suggest that these agents have practical implications in the treatment of mesangial proliferative glomerular diseases through the suppression of excess mesangial cell proliferation.     

Effect of amorphous silica nanoparticles on in vitro RANKL-induced osteoclast differentiation in murine macrophages

Amorphous silica nanoparticles (nSP) have been used as a polishing agent and/or as a remineralization promoter for teeth in the oral care field. The present study investigates the effects of nSP on osteoclast differentiation and the relationship between particle size and these effects. Our results revealed that nSP exerted higher cytotoxicity in macrophage cells compared with submicron-sized silica particles. However, tartrate-resistant acid phosphatase (TRAP) activity and the number of osteoclast cells (TRAP-positive multinucleated cells) were not changed by nSP treatment in the presence of receptor activator of nuclear factor κB ligand (RANKL) at doses that did not induce cytotoxicity by silica particles. These results indicated that nSP did not cause differentiation of osteoclasts. Collectively, the results suggested that nanosilica exerts no effect on RANKL-induced osteoclast differentiation of RAW264.7 cells, although a detailed mechanistic examination of the nSP70-mediated cytotoxic effect is needed.     

Bonding Properties of Liquid Crystalline Epoxy Resins Having Different Phase Structures

Liquid-crystalline epoxy resin systems, which have different phase structures (isotropic and nematic polydomain), were prepared. The bonding properties of their systems were investigated and related to their phase structure. As a result, the lap shear strength of the nematic system was lower than that of the isotropic system, although the nematic adhesive layer showed larger deformability than the isotropic one. The interfacial bonding properties of both the isotropic and nematic systems were investigated, and, thus, it was clarified that the low bonding strength of the nematic system was due to the low concentration of hydroxyl groups at the adhesive interface. The decrease in the concentration of hydroxyl groups was due to the restriction of the molecular motion derived from the ordered structure of the nematic system.