Stabilization of bioethanol recovery with silicone rubber‐coated ethanol‐permselective silicalite membranes by controlling the pH of acidic feed solution

In order to produce highly concentrated bioethanol by pervaporation using an ethanol‐permselective silicalite membrane, techniques to suppress adsorption of succinic acid, which is a chief by‐product of ethanol fermentation and causes the deterioration in pervaporation performance, onto the silicalite crystals was investigated. The amount adsorbed increased as the pH of the aqueous succinic acid solution decreased. The pervaporation performance also decreased with decreasing pH when the ternary mixtures of ethanol/water/succinic acid were separated. Using silicalite membranes individually coated with two types of silicone rubber, pervaporation performance was significantly improved in the pH range of 5 to 7, when compared with that of non‐coated silicalite membranes in ternary mixtures of ethanol/water/succinic acid. Moreover, when using a silicalite membrane double‐coated with the two types of silicone rubber, pervaporation performance was stabilized at lower pH values. In the separation of bioethanol by pervaporation using the double‐coated silicalite membrane, removal of accumulated substances having an ultraviolet absorption maximum at approximately 260 nm from the fermentation broth proved to be vital for efficient pervaporation. Copyright © 2005 Society of Chemical Industry     

Accelerated neutrophil apoptosis in mice lacking A1-a, a subtype of the bcl-2-related A1 gene

To elucidate the role of A1, a new member of the Bcl-2 family of apoptosis regulators active in hematopoietic cell apoptosis, we established mice lacking A1-a, a subtype of the A1 gene in mice (A1-a-/- mice). Spontaneous apoptosis of peripheral blood neutrophils of A1-a-/- mice was enhanced compared with that of either wild-type mice or heterozygous mutants (A1-a+/- mice). Neutrophil apoptosis inhibition induced by lipopolysaccharide treatment in vitro or transendothelial migration in vivo observed in wild-type mice was abolished in both A1-a-/- and A1-a+/- animals. On the other hand, the extent of tumor necrosis factor alpha-induced acceleration of neutrophil apoptosis did not differ among A1-a-/-, A1-a+/-, and wild-type mice. The descending order of A1 mRNA expression was wild-type, A1-a+/-, and A1-a-/-. Taken together, these results suggest that A1 is involved in inhibition of certain types of neutrophil apoptosis.     

Novel stabilization system for polypropylene via the Ziegler–Natta catalyzed polymerization in the presence of aluminum aryloxide

The aluminum aryloxide was prepared via the reaction of phenolic antioxidant, 3‐(3,5‐di‐t‐butyl‐4‐hydroxyphenyl)‐N‐octadecylpropionamide, with triethyl aluminum. Propylene polymerization using supported Ziegler–Natta catalyst systems was carried out in the presence of the antioxidant or its aluminum aryloxide. Although the antioxidant gave rise to decrease in catalyst yield and change in hydrogen response, the aluminum aryloxide had no influence on the catalytic polymerization behavior, and thus the obtained polymer characteristics such as molecular weight, polydispersity, and meso pentad as a stereoregularity were comparable to that polymerized without the antioxidant and the aluminum aryloxide. Polypropylene obtained in the presence of the aluminum aryloxide was well stabilized for oxidation and its stability was over 1000 h at 100°C (estimated to be over 30 years at room temperature). © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1350–1358, 2006     

Incorporation of [1-14C] acetate into phospholipids by soybean seedlings

Incorporation of [1-¹⁴C] acetate into lipids by slices of soybean seedlings was studied. The results were as follows: (a) the greatest amount of radioactivity was detected in the phospholipid fraction prepared from the main axis; (b) in the cotyledons, radioactivity was about the same in pigment, phosphatidylethanolamine, and phosphatidylglycerol; (c) phosphatidylcholine was the main phospholipid labeled in the axis; (d) the distribution of radioactive fatty acids in the axis suggested that this tissue has the capacity for both phospholipid synthesis and fatty acid desaturation.     

Determination of fatty acid composition by gas chromatography: II. Analysis with use of flame ionization detector

In this study known mixtures of four or five fatty acid methyl esters were analyzed collaboratively by gas chromatography with flame ionization detectors. The experimental data was treated statistically to examine inter- and intralaboratory scattering. More-over the effect of the use of correction factors was investigated. Even if only the specific analytical values that scattered a little were chosen, the averages of such values did not always approach the actual values. In some laboratories a sort of regularity was observed in the deviation of analytical values from real values throughout the analyses of four samples. The application of correction factors to the analytical values obtained by these laboratories resulted in a considerable decrease of interlaboratory scattering and deviation from the real values. When a constant amount of sample was injected, intralaboratory scattering was decreased, whereas interlaboratory scattering was not. Injection of large sample sizes caused deviation. From this collaborative study it was recommended that 0.5–1.0 μl of 20% solution be injected. Presented at the JOCS-AOCS Joint Meeting, Los Angeles, April 1972.     

Metal Single-Atom Cocatalyst on Carbon Nitride for the Photocatalytic Hydrogen Evolution Reaction: Effects of Metal Species

Single-atom (SA) catalysts exhibit high activity in various reactions because there are no inactive internal atoms. Accordingly, SA cocatalysts are also an active research fields regarding photocatalytic hydrogen (H₂) evolution which can be generated by abundant water and sunlight. Herein, it is investigated whether 10 transition metal elements can work as an SA on graphitic carbon nitride (g-C₃N₄; i.e., gCN), a promising visible-light-driven photocatalyst. A method is established to prepare SA-loaded gCN at high loadings (weight of ≈3 wt.% for Cu, Ni, Pd, Pt, Rh, and Ru) by modulating the photoreduction power. Regarding Au and Ag, SAs are formed with difficulty without aggregation because of the low binding energy between gCN and the SA. An evaluation of the photocatalytic H₂-evolution activity of the prepared metal SA-loaded gCN reveals that Pd, Pt, and Rh SA-loaded gCN exhibits relatively high H₂-evolution efficiency per SA. Transient absorption spectroscopy and electrochemical measurements reveal the following: i) Pd SA-loaded gCN exhibits a particularly suitable electronic structure for proton adsorption and ii) therefore they exhibit the highest H₂-evolution efficiency per SA than other metal SA-loaded gCN. Finally, the 8.6 times higher H₂-evolution rate per active site of Pd SA is achieved than that of Pd-nanoparticles cocatalyst.     

Mid-Gap State Formed Inside Mott Gap of 1T-TaS2 Single Crystals and Metal-Insulator Transition

We have measured electrical resistivity, Hall coefficient, thermoelectric power, and magnetization for charge-density wave (CDW) material 1T-TaS₂ single crystals grown by varying the excess sulfur content x _es. We have revealed that a small mid-gap state is formed inside the Mott gap and that anomalous low temperature transport is not governed by the Mott gap state itself but by the mid-gap state. The electric properties of the mid-gap state are modified by increasing x _es (or hole doping), and we have found the insulator-metal transition occurs by hole doping below 60K.     

Volatilization and recovery of mercury from mercury wastewater produced in the course of laboratory work using Acidithiobacillus ferrooxidans SUG 2-2 cells

The iron-oxidizing bacterium Acidithiobacillus ferrooxidans SUG 2-2 is markedly resistant to mercuric chloride and can volatilize mercury (Hg0) from mercuric ion (Hg2+) under acidic conditions. To develop a microbial technique to volatilize and recover mercury from acidic and organic compound-containing mercury wastewater, which is usually produced in the course of everyday laboratory work in Okayama University, the effects of organic and inorganic chemicals on the mercury volatilization activity of A. ferrooxidans cells were studied. Among 55 chemicals tested, the mercury volatilization from a reaction mixture (pH 2.5) containing resting cells of SUG 2-2 (1 mg of protein) and mercury chloride (14 nmol) was strongly inhibited by AgNO3 (0.05 mM), K2CrO7 (1.0 mM), cysteine (1.0 mM), trichloroethylene (1 microM), and commercially produced detergents (0.05%). However, the strong inhibition by trichloroethylene and detergents was not observed when these organic compounds were chemically decomposed using Fenton's method before the treatment of the wastewater with SUG 2-2 cells. When 20 ml of water acidified with sulfuric acid (pH 2.5) containing ferrous sulfate (3%), diluted mercury wastewater (17.5 nmol of Hg2+) and SUG 2-2 cells (0.05 mg of protein) were incubated for 10 d at 30 degrees C, 47% of the total mercury in the wastewater was volatilized and recovered into a trapping reagent for metal mercury. However, when the organic compounds in the mercury wastewater were decomposed using Fenton's method and then treated with A. ferrooxidans cells, approximately 100% of the total mercury in the wastewater was volatilized and recovered.     

Growth monitoring and classification of rice fields using multitemporal RADARSAT-2 full-polarimetric data

Spaceborne synthetic aperture radar (SAR) can be used for agricultural monitoring. In this study, three single-polarimetric and four full-polarimetric observation data sets were analysed. A rice paddy field in northern Japan was used as the study site; the data for this site were obtained using RADARSAT-2, which carries a full-polarimetric C-band SAR. Soybean and grass fields were also present within the paddy fields. The temporal change in the backscattering coefficient of the rice paddy fields for the single-polarization data agreed with the temporal change obtained for a rice growth model based on radiative transfer theory. A three-component decomposition approach was applied to the full-polarimetric data. With each rice growth stage, the volume scattering component ratio increased, whereas the surface scattering component ratio generally decreased. The soybean and grass fields showed a smaller double-bounce scattering component than the rice fields for all the acquired data. The results of this study show that multitemporal observation by full-polarimetric SAR has great potential to be utilized for estimating rice-planted areas and monitoring rice growth.