Control of the rhodium particle size of the silica-supported catalysts by using microemulsion

The control of the rhodium particle size of silica-supported catalysts by using microemulsion was investigated in terms of the structure of surfactants and organic solvents. The use of nonionic surfactants and anionic surfactants is effective for the preparation of catalysts having narrow size distribution. Especially, in nonionic surfactants, the rhodium particle size varied in the range of 3.0–8.2 nm according to the structure of surfactants and organic solvents regardless of rhodium content. The length of the hydrophilic group of surfactants and the carbon number of n-alcohol as an organic solvent were effective factors for the size control. The rhodium particle size increased with decreasing length of the hydrophilic groups of surfactants and with increasing carbon number of n-alcohol.     

Poly(ethylene oxide)/poly(propylene oxide)/poly(ethylene oxide) triblock copolymer as a sustained-release carrier for perfume compounds

The volatility behavior of perfume compounds in poly(ethylene oxide)/poly(propylene oxide)/poly(ethylene oxide) copolymer was investigated by means of dynamic and static headspace analyses. Suppression of the volatility of perfume compounds by EO₁₀₅PO₂₇EO₁₀₅ copolymer was markedly greater than by polyethyleneglycol. This suppressive effect may be due to micelle and gel formation of EO₁₀₅PO₂₇EO₁₀₅ copolymer. EO₁₀₅PO₂₇EO₁₀₅ copolymer is expected to be useful as a novel sustained-release carrier that maintains constant release rates for the volatility of perfume compounds over a wide temperature range.     

Phosphate group requirement for mitogenic activation of lymphocytes by an extracellular phosphopolysaccharide from Lactobacillus delbrueckii ssp. bulgaricus

The mitogenic activity of extracellular polysaccharides produced by Lactobacillus delbrueckii ssp. bulgaricus OLL 1073R-1 and NCFB2483 was examined in murine lymphocytes. The extracellular polysaccharide from Lactobacillus delbrueckii ssp. bulgaricus OLL 1073R-1 was fractionated into neutral and acidic polysaccharides by anion-exchange chromatography, while that of Lactobacillus delbrueckii ssp. bulgaricus NCFB2483 were all fractionated into neutral polysaccharide(s). The acidic polysaccharide stimulated mitogenic responses of murine splenocytes and Peyer's patches but not of thymocytes. The optimal concentration of the acidic polysaccharide at the highest stimulation was 160 μg/ml. A significant increase of mitogenic activity was initiated at 24 h, and the highest response was obtained after stimulation for 48 h. The acidic polysaccharide purified by high performance liquid chromatography also had substantial mitogenic activity, and the molecular weight was estimated to be 1.2×10⁶. The acidic polysaccharide was a phosphopolysaccharide consisting of glucose, galactose and phosphorus. Dephosphorylation by hydrofluoric acid degradation reduced the mitogenic activity in lymphocytes. The phosphopolysaccharide produced by Lactobacillus delbrueckii ssp. bulgaricus 1073R-1 is a potent B-cell-dependent mitogen in which the phosphate group acts as a trigger of the mitogenic induction.     

Risk‐based Replacement Scheme: Rational Replacement under Supply Risk

Though many studies on life extension of power apparatus have been carried out recently, it is inevitable to replace them in the not too distant future. However, if replacements of apparatus occur simultaneously, manufacturers may not able to supply the apparatus within a reasonable cost. This letter proposes a rational replacement scheme to avoid such supply risk. Copyright © 2008 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Numerical simulation of emulsified fuel spray combustion with puffing and micro-explosion

The purpose of this study was to develop numerical simulation of spray combustion of emulsified fuel with considering puffing and micro-explosion. First, a mathematical model for puffing was proposed. In the proposed puffing model, the rate of mass change of a droplet during puffing was expressed by the evaporation rate of dispersed water and the mass change rate due to fine droplets spouted from the droplet surface. The mass change rate due to fine droplets was related to the evaporation rate of the dispersed water and each liquid content. This model had only one experimental parameter. The essential feature of this model was that it was simple to apply to numerical simulation of spray combustion. First, the validity of the proposed puffing model was investigated with the experimental results for a single droplet. The calculated results for a single droplet with the experimental parameter varying from 5.0 to 10 were in good agreement with the experimental results. Moreover, numerical simulation of spray combustion of emulsified fuel was carried out. The occurrence of puffing and micro-explosion was determined by the inner droplet temperature. When micro-explosion occurred, a droplet changed to vapor rapidly. When the proposed puffing model was used in numerical simulation of spray combustion, the experimental parameter in the puffing model was determined for each droplet by random numbers within the range 5.0-10. The calculated results of spray combustion of emulsified fuel without considering puffing or micro-explosions were different from the experimental results even where combustion reactions were almost terminated. Meanwhile, the calculated results when considering puffing and micro-explosions were in good agreement with experimental results at the same location.     

Synthesis and properties of a cyclic oligo(aryl ether ketone) based on bisphenol A and its polymerization

A cyclic oligo(aryl ether ketone) based on bisphenol A (CBAEK) was successfully synthesized via the nucleophilic substitution reaction of 4,4'-difluorobenzophenone and bisphenol A with the use of pseudo-high dilution condition. The structure of the cyclic oligomer was characterized by IR and NMR spectroscopy as well as matrix-assisted laser desorption ionization time-of-flight mass spectroscopy (MALDI-TOF-MS), in comparison with those of the corresponding fluorine- and hydroxy-terminated linear (aryl ether ketone) oligomers (BAEK-F and BAEK-OH). From differential scanning calorimetry and wide angle X-ray diffraction measurements it was revealed that CBAEK exhibits a high degree of crystallinity, while BAEK-F and BAEK-OH are amorphous. Ring-opening polymerization of CBAEK proceeded smoothly in the presence of potassium carbonate at 400°C to give a linear poly(aryl ether ketone).     

Crystallization and melting behavior of poly(p‐phenylene sulfide) in blends with poly(ether sulfone)

Crystallization and melting behaviors of poly(p‐phenylene sulfide) (PPS) in blends with poly(ether sulfone) (PES) prepared by melt‐mixing were investigated by differential scanning calorimetry (DSC). The blends showed two glass transition temperatures corresponding to PPS‐ and PES‐rich phases, which increased with increasing PES content, indicating that PPS and PES have some compatibility. The cold crystallization temperature of the blended PPS was a little higher than that of pure PPS. Also, the heats of crystallization and melting of the blended PPS decreased with increasing PES content, indicating that the degree of crystallinity decreased with an increase of PES content. The isothermal crystallization studies revealed that the crystallization of PPS is accelerated by blending PPS with 10 wt % PES and further addition results in the retardation. The Avrami exponent n was about 4 independent on blend composition. The activation energy of crystallization increased by blending with PES. The equilibrium melting point decreased linearly with increasing PES content. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1686–1692, 1999     

Depolymerization of poly(butylene terephthalate) using high‐temperature and high‐pressure methanol

Poly(butylene terephthalate) (PBT) was depolymerized in excess methanol at high‐temperature (473–523 K) and high‐pressure (4–14 MPa) conditions. Considering the critical point of methanol (512.6 K, 8.09 MPa), the reaction pressure was varied over the range of 6–14 MPa at the reaction temperature of 513 K. As a result, ca. 20 min was required to recover dimethyl terephthalate and 1,4‐butanediol, quantitatively, at any pressure, indicating that the supercritical state of methanol is not a key factor of degradation of PBT and that the effect of pressure is little. On the contrary, when the reaction temperature was varied over the range of 473–523 K at the pressure 12 MPa, the decomposition rate constant of PBT at the reaction temperatures (503–523 K) higher than the melting temperature of PBT (500 K) was much higher than that at 473–483 K. This result indicates that melting of PBT is an important factor for the short‐time depolymerization of PBT. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 3228–3233, 2000     

Effect of air space in waterproof sealed case containing transmitter and receiver of wireless power transfer in sea water

In this study, the effect of air space in waterproof sealed case of undersea magnetic field resonance type wireless power transfer (WPT) is reported. It has been reported that the transmission power is increased by the air space between the transmitter and receiver coil in the waterproofing case and the wall surface of the case. We evaluated the dependence of the thickness of the air space from measurement and magnetic field analysis. The measurement and magnetic field analysis results indicated the similar tendency to increase the transmission power by 9.8% with the 10‐mm air space at the transmitter side and the 30‐mm air space at the receiver side.     

Purified Canola Lutein Selectively Inhibits Specific Isoforms of Mammalian DNA Polymerases and Reduces Inflammatory Response

In the screening of DNA polymerase (pol) inhibitor, we isolated lutein, a carotenoid, from the crude (unrefined) pressed oil of canola (low erucic acid rapeseed, Brassica napus L.). Commercially prepared carotenoids such as lutein (1), zeaxanthin (2), β-cryptoxanthin (3), astaxanthin (4), canthaxanthin (5), β-carotene (6), lycopene (7), capsanthin (8), fucoxanthin (9) and fucoxanthinol (10), were investigated for the inhibitory activities of pols. Compounds 1, 2 and 8 exhibited strong inhibition of the activities of mammalian pols β and λ, which are DNA repair- and/or recombination-related pols. On the other hand, all carotenoids tested had no influence on the activity of a mammalian pol α, which is a DNA replicative pol. Lutein (1) was the strongest pol inhibitor of mammalian pols β and λ in the prepared ten carotenoids tested, but did not influence of the activities of mammalian pols α, γ, δ and ε. The tendency for pols β and λ inhibition by these carotenoids showed a positive correlation with the suppression of TPA (12-O-tetradecanoylphorbol-13-acetate)-induced inflammation. These results suggest that cold pressed unrefined canola/rapeseed oil, or other oils with high levels of lutein and other carotenoids, may be useful for their anti-inflammatory properties.