Fabrication of optically transparent cotton fiber composite

In this study, we fabricated optically transparent cotton fibers composite by resin impregnation without having to prepare cellulose nanofibers. Although the surface acetylation of the cotton microfibrils aided the resin impregnation process, excess acetylation resulted in the gradual breakdown of the cellulose crystal structure, with the resulting composite showing a high coefficient of thermal expansion (CTE). To prevent this, a swelling pretreatment, namely surface carboxylation by TEMPO-mediated oxidation, was performed to facilitate the surface acetylation of the microfibrils and hence the resin impregnation process. After the swelling pretreatment and the subsequent surface acetylation process, an optically transparent cotton fiber composite with a high regular light transmittance (83.23% at 600 nm) and a low CTE (19.5 ppm/K) was obtained. Finally, when this technique was used with a commercial cotton cloth, a transparent composite with a high total transmittance (88.5% at 600 nm) could be obtained.     

Effect of Anti-Encrustation Additives on Zirconium Molybdate Hydrate

Anti-encrustation additives were mainly investigated in nitric acid solution with zirconium (Zr), molybdenum (Mo), and tellurium (Te) to prevent the encrustation of zirconium molybdate hydrate (ZMH). The ZMH generated by reaction crystallization of Mo and Zr as main fission products has a high adhesion property in spent nuclear fuel reprocessing. In addition, it is reported that Te, which is also one of the fission products, precipitates together with ZMH. Encrustation of precipitates containing Te was effectively prevented by adding molybdenum trioxide (MoO₃) crystals as an anti-encrustation reagent. The encrustation amount was found to be larger than that under the condition of only Zr and Mo without Te. Consequently, it was suggested that the high adhesion property of Te affected the encrustation amount of ZMH.     

Involvement of actin and polarisome in morphological change during spore germination of Saccharomyces cerevisiae

We studied the morphological changes of Saccharomyces cerevisiae ascospores during germination. Initiation of germination is followed by polarization of actin patches, maintaining their localization to the site of cell surface growth. Loss of polarisome components, Spa2p, Pea2p, Bud6p or Bni1p, results in depolarization of actin patches. Green fluorescent protein-fused polarisome components exhibit the polarized localization, implying that polarisome is involved in the polarized outgrowth during germination. At the late stage of germination, we found that actin patches temporally depolarize before bud emergence. The observation that loss of Cla4p extends the polarized growth period suggests that Cla4p is involved in the actin-depolization step. Actin polarization in the initial stage is accelerated by overexpression of Ras2p, whereas hyperpolarization is continuously observed by overexpression of Rho1p. Thus, yeast spore germination is a morphological event that is regulated by a number of factors implicated in mitotic bud morphogenesis.     

Diltiazem blood cardioplegia in patients of severe valvular heart disease

This study was undertaken to analyze the effect of diltiazem blood cardioplegia (D-BCP) in patients of valvular heart disease with severe left ventricular dysfunction (EF = 56.3%, FS = 26.0%, CI = 2.241/min/m3), they were satisfied with NYHA functional class 3 and 4, also cardiothoracic ratio over 65%. By negative choronotropic action of D, the heart rates in D added group tend to be less than those of D free group 4 to 16 hours postoperatively, although that may diminish the incidence of ventricular arrhythmia postoperatively. D-BCP improved better functional recovery (mPAWP-LVSWI relation) during the early postoperative period than those seen in preoperatively. The pulmonary vascular resistance index of D added group showed significantly lower levels than those in the preoperative period, 0 to 16 hours after surgery. Consequently, D-BCP might be safe and provide superior protection for severe valvular heart disease.     

A strain sensor using twisted optical fibers

A sensor using twisted optical fibers to detect the strain distribution along the length of an object is discussed. This sensor is based on the optical loss due to fiber curvature. The distributed strain along the sensor axis is converted into distributed optical loss. The relation between the strain and optical loss is theoretically derived and experimentally confirmed for uniform tensile strain. The dependence of the sensor characteristics on sensor structure and fiber parameter are also shown. Measurement of the strain applied to fibers in an optical cable is also discussed     

Alanine metabolism in pyridoxine-depleted rat liver

Alanine metabolism in normal and pyridoxine-deficient rats was studied in vivo and in vitro. Incorporation of 14C-alanine into various liver components was determined and no difference was shown between normal and deficient animals in the incorporation into liver homogenates, lipid, protein and plasma glucose. Using the liver slice syste, gluconeogenic activity from alanine or pyruvate was 40% lower in deficient rats compared with the activity of normal rats. However, inhibition was completely removed by the addition of 2-oxoglutarate to alanine. Penicillamine did not affect glucose formation alanine in the liver slice.     

The activity of transition metal nitrides for hydrotreating quinoline and thiophene

An investigation has been conducted of the activity of AlN, BN, TiN, VN, Mo₂N, and W₂N as catalysts for quinoline hydrodenitrogenation (HDN). The activity of Mo₂N and VN for thiophene hydrodesulfurization (HDS) and the concurrent hydrotreatment of quinoline and thiophene have also been examined. Bulk AlN, BN, and TiN were obtained with low surface areas and found to be inactive for the HDN of quinoline. Bulk Mo₂N, W₂N, and VN could be obtained with high surface area. Each of these nitrides exhibited high activity for quinoline HDN, the turnover frequency for this reaction decreasing in the order Mo₂N>W₂N>VN. Highly dispersed VN supported on SiO₂ was found to have a specific activity for quinoline HDN identical to that of bulk VN. Both bulk Mo₂N and 27% VN/SiO₂ exhibit high activity for the HDS of thiophene. The behavior of these two catalysts for the concurrent hydrotreatment of quinoline and thiophene is also discussed.     

Thermal conductivity of ramie fiber drawn in water in low temperature

To understand the effect of extension of molecular chain in amorphous region in polymer fibers to thermal conductivity, the thermal conductivity, tensile modulus and crystal orientation angle of ramie fibers and those drawn by the stress of 17.4 kg/mm² (water treatment) in the water were investigated. The tensile modulus of ramie fiber in fiber direction increased from 61 to 130 GPa by drawing in the water. The crystal orientation angles of ramie fiber with and without water treatment were measured by X‐ray diffraction. The orientation degrees of ramie fibers without and with water treatment were estimated as 92.9 and 93.6%, respectively. Therefore, the tensile modulus increases two times as that of blank ramie by water treatment although crystal orientation angle does not change distinctly. The increasing of tensile modulus of ramie fiber by water treatment was explained by extension of the molecular chains in the amorphous region. Thermal conductivities of ramie fibers with and without water treatment were measured in the fiber direction in the temperature range from 10 to 150 K. Thermal conductivity of ramie fiber in the fiber direction increased by water treatment. The increasing ratio of thermal conductivity by water treatment agreed to that of sound velocity induced by increasing tensile modulus. Those results suggest that thermal conductivity of polymer fiber increase by the extension of molecular chains in the amorphous region. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2196–2202, 2006