Oils, petroleum products, plastics etc. are degraded by autoxidation, and the inhibition of such oxidations is an important problem. Phenols, used for such purposes, are known to show activities depending on t heir molecular structures, especially substituents on p henolic nuclei; the relationship betwe en activity and substituent was established in the 1960's. Consequently, new phenols have not been developed since. The authors have some doubts about the relationship, and molecular-designed phenols having an olefinic group on ο-position (ο-hydroxycinnamates) as new antioxidants. Surprisingly, they were more highly active than phenols developed in the past. The high acitivities were found to be derived from (1) the enhancement of peroxyl radical-trapping rate due to the high stability of the phenoxyl radical, (2) the inhibition of coupling of phenoxyl radicals by localization of the electron of t he phenoxyl radical, and (3) the trapping of peroxyl radicals. The effect of other substituents, in addition, was examined as well, and more active phenols were synthesized by introduing two substituents on ο-and ρ-positions of the hydroxy group. The reason, why ο-hydroxycinnamates exhibit such high activities, was discussed by a semi-empirical molecular orbital method, and a possible action mechanism was proposed.

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The paper introduces development of the molecular probe for bioimaging of nitrogen monoxide (NO). First, we review the biological importance of NO and the NO detection methods. There are several strategies used most widely to detect NO: 1) a chemiluminescence assay based on the reaction of NO with ozone, 2) a spectrophotometric assay which measures the product in the nitrite azo-coupling reaction, 3) an oxidation assay of hemoglobin to methemoglobin by NO, 4) a GC/MS assay for direct detection of NO, 5) electron paramagnetic resonance (ESR) assay for detection of a stable adduct formed in the reactions of NO and certain compounds, 6) electrochemical assays with specific electrodes for NO, 7) radioisotope assay, 8) fluorescence assay using 2, 3-diaminonaphthalene, and 9) chemiluminescence assay with luminol + hydrogen peroxide system. Secondly, we introduce how to develop the novel probes, diaminofluoresceins (DAFs), for detection of NO produced in living cells, tissue cultures or in vivo s ystems. Finally DAFs are applicable for detection of NO produced from induced NO synthase (i-NOS) or constitutive NO synthase (c-NOS). In addition, we review the biological application of 3', 6'-diacetoxy5, 6-diaminospiro [isobenzofuran-1 (3H), 9'-[9H] xanthen] -3-one (DAF-2DA) useful for bioimaging of NO in living cells.

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Cathodic oxygen reduction reaction on a steel in neutral unbuffered sodium chloride solutions was studied by a linear potential sweep technique. The experiment was performed before the steel lost its luster in order to avoid the complication resulting from the corrosion products.
The steady state current was observed at the potential sweep ra te ranging from 0.5 to 10 mVs^-1. The steady state polarization curves showed no significant hysteresis. The cathodic Tafel slope was -130mV/decade and the reaction order was 0.5 with respect to the partial pressure of oxygen. The concentration of NaCl did not affect the cathodic current. The mechanism of oxygen reduction reaction was disccussed.

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Hydrogels of silica, alumina, and five silica-aluminas were prepared with aqueous solutions of sodium silicate and aluminium nitrate using the instantaneous mixing method. For purification the hydrogels were dispersed with a fixed volume of de-ionized water against a gel using high speed mixer (150 rps) and then filtrated. Such operations with water repeated up to fifth, and finally the same operation with ammonia water was added. The seven hydrogels were calcined, ground and sieved to be these xerogels with the size under 100 mesh. Resulting from the decrease of sodium remained with repetition of filtration for all the hydrogels, a mechanism how the sodium was removed from the gels through washing process, was considered. Moreover, it was considered how the sodium remained has influences on solid acid amount, catalytic activity for isomerization of 1-butene and specific surface area.
In silica-rich gels, a large amount of sodium is caught into the bulk phase, and that sodium can not be removed, consequently the sodium remained became high. Because sodium acts as base to neutralize acid sites, removal of the sodium results to bring about recovery of latent acid sites, followed by increasing amount of solid acid sites and catalytic activity. Generation of strong acid sites results in increase in the surface area, because sintering is depressed by repulsion of surface charge between the primary particles. Increasing of the specific surface area agreed with increasing of the acid amount of strong acid region.

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Ammonium-ion exchange experiment has been carried out on the cation exchange property of the fibrous titanium dioxide hydrate having layer structure. The sum of the yield ion-exchanged and adsorption in aqueous ammonium solution increased with reaction time and reached 3.7 mmol/g at the maximum within 24 h. It was found that those two kind of yields, by adsorption on the surface and by ion-exchange, could be distinguished from each other. The composition of the substance obtained after the ion-exchange was (NH₄) _1.0H_1.0Ti₄O₉·nH₂O, n≅1, of which chemical properties was examined.

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Functional group transformation reaction of α-trifluoromethylated alcohols was investigated. Nucleophilic substitution of the trifluoromethylated alcohol derivatives is difficult to proceed because of high electronegativity of the fluorine atom. It was revealed that the substitution reaction was achieved by conversion of the alcohols into trifluoromethanesulfonic ester. This reaction took place by using salts of carboxylic acids as nucleophiles, and in S_N2 manner with complete inversion of configuration of the substrate. It was found that alkali metal salts were good nucleophiles but heavy metal salts were not. As the nucleophiles, not only the carboxylic acid salts, but also dithiocarboxylic acid salt and even inorganic salts were also applicable.

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1, 6-Anhydro-2-deoxy-glucose derivatives having two kinds of protective groups were polymerized and copolymerized in order to synthesize branched polysaccharides. Deoxy-glucose monomers showed high polymerizability. The obtained polymer was selectively deprotected and then glucosylated to give 2-deoxy- (1→6) -α-D-glucopyranan with glucose branch at C-3. In the present report, it is firstly described that the comb-shaped branched polysaccharide (100% branching) was synthesized by the glycosylation of the polysaccharide derivative.

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A polyurethane film that is useful for medical application, especially for wound dressing, was prepared, and its physicochemical properties were investigated. Bis (4-isocyanatocyclohexy1) methane was allowed to react, in the presence of a catalyst, with polyol derived from tetrahydrofuran and ethylene oxide, and the intermediate prepolymer then reacted with isophorone diamine to form segmented polyurethane consisting of “soft” and “hard” segments. The physicochemical properties of the polyurethane, synthesized under industrial scale, were the same as those of the polyurethane, prepared in a loboratory scale. DMF was removed by blowing hot air on the surface of a thin layer of the polyurethane solution to prepare a thin film of the polyurethane with 10-100 μm thickness. The newly prepared polyurethane film which contained as high polyol moieties as possible showed the highest water vapor-permeability. Besides high water vapor-permeability, the film had such features as low size-increase-ratio under water absorption conditions, high UV light resistance, high mechanical strength, large elongation, and low toxicity. The selection of the polyurethane film (from the viewpoints of both thickness and water vapor-permeability for the best wound dressing material) was also studied referring the volume of lost water vapor from the surface of wound patients' skin, proposed by Lamke et al.

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A novel wound dressing was prepared from a polyurethane film, which has high water vapor-permeability, and a non-woven fabric, which has high water absorbing capacity. An antibiotic, N- (1, 3-diazin-2-y1) sulfanilamide silver salt (silver sulfur diazine), was dispersed without localizaton in the polyurethane film. Using two dispersion methods, silver and/or sulfur atoms of the antibiotic were homogeneously dispersed in the polyurethane film, which was confirmed by an X-ray fluorescence analysis or an atomic absorption spectrometry. In order to vest high water absorption capacity to the nonwoven fabric, an appropriate ratio of a conjugated polyester and a rayon was selected. Then the mixed fiber was treated with hot air of 160 °C to form a unique non-woven fabric which could absorb 20 g water per one gram of the fabric.
Next, using a coater mach ine, a roll of sheet for the final wound dressing was prepared by laminating the antibiotic-impregnated polyurethane and the non-woven fabric. The following manufacturing conditions for unit processes, a) -f), were investigated, and finally a roll of laminated sheet was produced under the best conditions determined. Conditions studied: a) preparation of polyurethane isopropyl alcohol solution, b) dispersion of antibiotic, c) selection of carrier paper, d) dryness of laminate (removal of solvent), e) roller pressure during lamination, f) slitter pressure.

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Mixtures of sodium dihydrogenphosphate (NaH₂PO₄) with biuret, cyanuric acid, or melamine were heated in a stream of nitrogen gas. Crystalline sodium polyphosphate of high-temperature type of Maddrell's salt was produced at above 300 °C in the NaH₂PO₄-cyanuric acid or NaH₂PO₄-melamine mixtures. Sodium cyclo-triphosphate was produced in the NaH₂PO₄-biuret mixture in a similar manner to the thermal reaction of NaH₂PO₄-urea mixture reported previously, which was considered to be responsible for the enhanced water-vapor pressure in samples caused by the the formation of a kind of “shell. ” An increase in amount of biuret added was available for the formation of cyclo-triphosphate.

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ABA block copolymers of DL-amino acids and alkylene oxide were studied as alignment films for ferroelectric liquid lciqryusitda ls (FLC). When the equal amount of D-NCA (N-carboxyamino acid anhydride) and L-NCA was mixed at first and polymerized as an ABA block copolymer with α- (3-aminopropy1) ω-aminoethylpoly (oxyethylene) [poly (ethylene oxide) diamine], uniform alignment of FLC was observed on the copolymer. When _D-NCA and _L-NCA were added one by one, uniform alignment of FLC was not observed. Furthermore, block copolymer of DL-γ-methyl glutamate and alkyleneoxide aligned FLC normal to the rubbing direction of the thin film. In the case of block copolymer of ethylene oxide and _DL-leucine, FLC was aligned in parallel to the rubbing direction.

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