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Polyphenylcarbosilane as a novel preceramic polymer for SiC was synthesized by thermal rearrangement of polymethylphenylsilane at around 350–430 °C. Characterization of the synthesized polyphenylcarbosilane was performed using 29Si NMR, 13C NMR and 1H NMR spectroscopy, FT-IR spectroscopy and TG, XRD, and GPC analysis. From the FT-IR data, the band at 1035 cm−1 was very strong and was assigned to the CH2 bending vibration in the Si–CH2–Si group, indicating the formation of polyphenylcarbosilane. The average molecular weight (Mw) of the polyphenylcarbosilane synthesized was 2,500, and it was found to easily dissolve in an organic solvent. TGA data indicate that polyphenylcarbosilane is thermally stable up to 200 °C. However, rapid weight loss occurs above 200 °C because of the decomposition of polyphenylcarbosilane, and the diffraction peak of the pyrolysis residue at 1200 °C corresponds to β-SiC ceramic. The ceramic yield calculated from TGA is approximately 60%. [ABSTRACT FROM AUTHOR]

The purpose of this practitioner research was to examine my role as a teacher in the context of children's conflicts in an early childhood special education classroom, reflecting on my reactions and choices of different intervention strategies. From videotaped observations and reflective journals I examined when I intervened and what strategies I used. The findings indicate that even though I was not conscious of my assumptions about individual children all the time, these assumptions were unconsciously translated into my daily practice and conflict resolution strategies. Through reflecting on my practices and beliefs I raised important issues concerning a teacher's role in children's conflicts. This study validates how important it is for teachers to reflect on specific issues within their practices and observe how these issues are addressed within the research process. Reflective practices, specifically conducting action research, not only heightens awareness of context but also enables one to take greater control over his/her own professional growth. [ABSTRACT FROM AUTHOR]

Bismuth metal, activated by ammonium hydrogen fluoride, was found to reduce various α-halocarbonyl compounds efficiently and chemoselectively in aqueous media to give the dehalogenated reduction products in excellent yields. [ABSTRACT FROM AUTHOR]

Bismuth metal, upon activation by zinc fluoride, can effect the crossed aldol reaction between α-bromocarbonyl compounds and aldehydes in aqueous media. The reaction was found to be regiospecific and syn-diastereoselective. [ABSTRACT FROM AUTHOR]

Investigates the isolation of cubanethiol and the synthesis of dicubyl disulfide. Properties of cubane derivatives; Stability of ketones; Structure of C-S bond of dicubyl disulfide.

The whole extract or isolated compounds of mushroom have shown biologic effects such as modulation of the immune system. The aim of the present study is to investigate hepatoprotective and immunomodulative activities of water extract from Grifola frondosa, a popular mushroom in Asia for its tasty flavor, against carbon tetrachloride (CCl4)-induced liver injury. Administration of CCl4 (1 ml/kg body weight for 3 days) caused liver injury revealed as increased the serum level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and local infiltration of inflammatory cells. CCl4 administration also induced immunosuppression as indicated by decreased expression of IL-6 and increased expression of MCP-1 and MMP-2. The pre-administration of water extract from Grifola frondosa for 14 days significantly prevented the changes in AST/ALT activity and altered expression of IL-6, MCP-1, and MMP-2 in liver tissue. In addition, water extract from Grifola frondosa blocked the local infiltration of inflammatory cells in the liver. These results indicate that the water extract from Grifola frondosa may have a protective role against CCl4 toxicity in the liver of rat. [ABSTRACT FROM AUTHOR]