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  • Author: Y. Tomita x
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Abstract

Small samples of tobacco powder, prepared by grinding the dried tobacco leaves, were heated in a micro-thermo-balance in different atmospheres and at different heating rates. The size distribution and the mass concentration of the smoke particles produced were measured simultaneously with a laser particle counter and a piezo balance mass monitor. In addition, the change of weight loss with time was also measured during each experiment. It was found that a larger amount of smoke particles was produced when tobacco was heated in the atmosphere of inert gas and/or at higher heating rates. Furthermore, comparison of measured and calculated size distributions showed that the particle size distribution was governed mainly by coagulation.

Summary

A new resin system, in which liquefied wood was reacted with various epoxy compounds, was previously developed. This paper reports the syntheses of two types of liquefied wood/epoxy resins with the ratio of liquefied wood to epoxy compounds (L/E ratio) of either 1/0.5 or 1/1. Furthermore, the viscoelastic properties obtained from the dynamic mechanical measurements of the cured resins and their adhesive bond properties measured as tensile shear strength are reported. The results from dynamic mechanical measurements indicated that the resins with a L/E ratio of 1/0.5 could be cured at 90°C, while the resins with L/E ratio of 1/1 were cured at 150°C. The resins cured with triethylene tetramine (TETA) at 150°C or 90°C had almost the same level of the normal adhesive shear strength as that of the commercial epoxy resin. The high level of adhesive shear strength of the resin cured at 150°C was maintained after the glued specimens were soaked in water at 60°C, while the share strength of the resins cured at 90°C was reduced by either the water soaking at 60°C or the cyclic boiling test.

Abstract

Optical characteristics of capillary U-tube Ar-Hg high frequency glow discharge plasmas were experimentally investigated. Based on optimization study of UV emission attenuations, the contaminated water treatment reactor based on bubbly column was developed, and NH4OH neutralization characteristics in demineralized water were obtained with and without photo-catalyst TiO2 . The results show that 1) The optical intensity increases with increasing applied voltage and decreases with increasing distance between sensor and tube; 2) The optical intensities for UV-A, -B and -C were observed; 3) Optical intensity can be enhanced by placing a UV mirror; 4) NH4OH in water can be neutralized by superimposing an external UV emission with TiO2 and aeration into the solution, where a significant shorten water treatment time was observed.

Singlet oxygen was generated by the photosensitization of erythrosine. The lifetime of singlet oxygen and the quenching rate constant for singlet oxygen by NaN3 were measured by a thermal lensing method in MeOH-H2O mixed solvents. The reciprocal of the lifetime increased linearly with the increase of the H2O mole fraction. Semi-log plot of the quenching constant against the reciprocal of the solvent polarity exhibited a linear relation. The quenching of the singlet oxygen by NaN3 may proceed through a partial charge-transfer intermediate. The activation energy for the quenching reaction of N3 - + 1O2 →[N3·1O2 -] increased with the increase of the solvent polarity. The lifetime was also measured in MeOH-ethyleneglycol mixed solvents, and its relation with viscosity was obtained

Abstract

We have cloned the gene of a new transmembranetype serine protease from rat kidney, which activates sodium channels. The amino acid sequence deduced from a full-length cDNA revealed that transmembrane serine protease-1 (TMSP-1) is a member of the clan SA/family S1 of serine proteases, comprising a 30 amino acid prepropeptide, a mature form sequence of 274 amino acids starting with the Ile-Val-Gly-Gly-Gln motif, and a common catalytic triad of serine proteases. The hydrophobic amino acid sequence in the carboxyterminus of this enzyme suggests that it is a glycosylphosphatidylinositol-anchored protein. As revealed by quantitative reverse transcription-polymerase chain reaction analysis, it is highly expressed in kidney, small intestine, and stomach, and moderately expressed in lung, thymus, spleen and skin. The recombinant protease had an optimal pH at 9.0, selectively cleaved synthetic peptide substrates of trypsin, and was inhibited by aprotinin, leupeptin and benzamidine. Immunohistochemical studies revealed that this protease is predominantly expressed in cells from collecting ducts of the renal medulla. We also demonstrate that a C-terminally truncated variant of TMSP-1 significantly activates the epithelial sodium channel, and that its mRNA levels are upregulated by aldosterone. These observations suggest that it is a new member of the trypsin-type transmembrane proteases, which regulate sodium balance by activating the epithelial sodium channel.