This paper describes the sensing characteristics of conductive polymer/enzyme-coated microarray electrodes consisting of assembly of microband electrodes with a few μ m width and a few mm length. The sensing principle of the array devices is based on detection of conductometric changes induced by chemical reactions of analytes. The followings are the contents of this paper: 1. Fabrication of ultrathin conductive polymers at hydrophobically-pretreated microarray electrodes. 2. n situ conductivity measurements using microarray electrodes coated with conductive polymers. 3. Redox behavior of polypyrrole-coated microarray electrodes. 4. NADH switching behavior of polypyrrole/diaphorase-coated microarray electrodes. 5. pH sensing behavior of polypyrrole- or polyaniline-coated microarray electrodes. 6. Penicillin sensing behavior of polypyrrole/penicillinase -coated microarray electrodes. 7. Glucose sensing behavior of polyaniline/glucose oxidase-coated microarray electrodes.

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Although it has been reported that 9, 9-bis (9-fluorenyl) fluorene (1) which belong to a class of compounds of Csp³-Csp³-Csp³ system has two stable rotational isomers at room temperature, we confirmed that this compound 1 existed only in the gauche-gauche form at room temperature by DNMR method. On the derivatives of 9-aryl-9, 9'-bifluorenyl (2) (belong to Csp³-Csp³-Csp² system) and 9, 9-diarylfluorene (3) (belong to Csp²-Csp³-Csp² system), it was able to presume that their two C-C single bonds rotated as gear bit each other, respectively. On 9, 9'-bifluorenyl derivatives (4) (belong to Csp³-Csp³ system) which have substituents at 1 or 1, 8-positions of fluorene ring, we observed a remarkable rotational barrier in the C-C single bond. As the compounds of Csp³-Csp² system (5), many 9- (2-substituted phenyl) fluorene derivatives and 1-substituted or, 1, 8-disubstituted 9- (2-methylphenyl) fluorene derivatives were chosen to investigate their conformational equilibrium between anti and syn conformers which was revealed by the restricted rotation of the C-C single bond. In these cases, the conformational equilibrium was able to explain due to their electronic and steric interaction between the two substituents or the substituent and the fluorene ring.

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The natural polymer “ chitin” has the property of being an anion-exchanger in an acidic medium, because the acetylamino groups of chitin are protonated in an acidic medium. The property of chitin was applied to the preconcentration and determination of sub ppb level of Au (III) by adsorption to the chitin as their anionic complex with metal furnace atomic absorption spectrophotometry. Au (III) reacts with anion such as halogenide ion, cyanide ion to form the anionic complex. The adsorption isotherm of Au (III)as their anionic complex on the chitin was known to be fitted by. Freundlich equation. The adsorption quantity of Au (III) as their anionic complex becomes larger in order of the complex, chloro anionic complex, bromo anionic complex, iodo anionic complex, cyano anionic complex. Especially, Au (III) was quantitatively collected as its chloro anionic complex on chitin over the range of pH 2.0 to 4.0. The chitin which adsorbed the Au (III) was separated from the sample solution with a membrane filter and dispersed in pure water. The resulting suspension was introduced directly into the tungsten metal furnace atomizer. The detection limit for Au (III) was 0.05 μg/500 cm³ (S/N ≥ 3). The proposed method was a plied to the determination of trace amounts of Au (III) in several water samples.

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The adsorption behavior of octadecylsilylated silica gel (ODS) particles which were loaded with bis (2-ethylhexyl) hydrogenphosphate (B2EHP) was studied for a series of rare-earth metal ions (RE)except Pm³⁺ in the dilute HCl solution. Based on the resultant adsorption equations for each metal ion, each RE was separated by the flash column chromatography using ODS particles loaded with B2EHP as the solid phase in high efficiency. Pairs of neighboring ions in the atomic number such as La³⁺-Ce³⁺, Ce³⁺-Pr³⁺, Sm3³⁺-Eu³⁺, Eu³⁺-Gd³⁺ and Tb³⁺-Dy³⁺ were separated each other completely by developing with 0.20 M to 1.2 M HCl at the eluting rate of 100 cm³/h and 45° C. At the smaller eluting rate, Pr3+ was separated from Nd³⁺. The heavier ions than Ho³⁺ were separated from their neighboring ions in the value of distribution ratio by developing with 1.8-3.5 M of HCl at the eluting rate of 30 cm³/h and 45° C. On the other hand, the separation of Y³⁺-Er³⁺ pair was incomplete with the resolution =0.52, coinciding with its smallest separation factor, 1.10 calculated from the present data of distribution ratios, among all the pairs.

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In reductive alkylation reaction of coals with molten potassium, the influence of hydroxy groups in the coals on the yields of soluble products has been studied. It was found that a significant amounts of hydroxy groups remained unchanged after the reductive alkylation reaction of the coals. Perhaps this is because reactivity of various hydroxy groups in the original coals was low due to hydrogen bridging in coal structure. When the coals were selectively O-methylated prior to the reductive alkylation reaction, remarkable increase of the amounts of soluble products was observed. Thus, it turned out that character or amount of various kinds of hydroxy groups in the coal significantly affects the yields of soluble products.

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Copolymer beads having 2-chloro-3-hydroxypropyl group (RCG) were prepared by treating macroreticular glycidyl methacrylate (GMA)- 1, 4-divinylbenzene (DVB) copolymer beads (RG) with hydrogen chloride. RCG-TEP, RCG-TBP, and RCG-TOP were prepared by treating RCG with triethylphosphine (TEP), tributylphosphine (TBP), trioctylphosphine (TOP), respectively. Decyldimethylphosphine (DMDP) dodecyldimethylphosphine (DMDDP), tetradecyldimethylphosphine (DMTDP), and hexadecyldimethylphosphine (DMHDP) were used as alkyldimethylphosphines which had an alkyl group with different length. Tris (3-aminopropyl) phosphine (TAPP) and tris (3-hydroxypropyl)phosphine (THPP) were also used as phosphines. The antibacterial activity was examined against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Antibacterial activity was evaluated by measuring the decrease in the number of viable cells in the bacteria suspension after contacting with the resins for prescribed time.
RCG-TOP exhibite d high antibacterial activity against E. coli and S. aureus in water, however RCGTEP and RCG-TBP did not. RCG-TAPP had high antibacterial activity, while RCG-THPP did not. All the resins which were made by treating RCG with alkyldimethylphosphines described above had high antibacterial activity for bacteria. The resins which exhibited high antibacterial activity had high adsorption ability for anionic compounds such as dodecylbenzensulfonic acid. These results indicate that the antibacterial activity of the resins against bacteria was not only affected by the amount of phosphonium introduced but also the length of alkyl groups and functional groups in the phosphonium residues.

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The 6-O-carboxymethylchitin (CM-chitin) is a chelating polymer. Rheological properties of CM-chitin solution are varied by chelating with metal ions and also depend on the affinity between metal ions and CM-chitin. CM-chitin aqueous solution forms a gel by introducing some kind of trivalent metal cations. The gel attracts attentions for high potential of medical polymer, but the effects of added metal cations on the gelation are not clear. In the present study, these effects are investigated through the rheological properties of the systems. The rheological properties of the CM-chitin aqueous solution added various concentrations of AlCl₃, GaCl₃, or InCl3₃ re measured using a cone-and-plate type rheometer at 25° C. It is revealed that the salt concentration required for gelation of CM-chitin aqueous solution increases in the following order; InCl3₃ < AlCl₃ < GaCl₃. This result is likely attributed to the fact that the constraint in the molecular motion of CM-chitin by In³⁺, Al³⁺, or Ga³⁺ ions in the aqueous solution is decreasing in the following order; In³⁺ > Al³⁺ > Ga³⁺.

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The residue in the preparation of adzuki bean paste was dried and milled (it was designated AZ). AZ allowed to react with 1, 3, 5-triacryloylhexahydro-1, 3, 5-triazine. The adsorbent obtained was designated TAZ. The adsorptive properties of these substrates were examined for Cu²⁺, C. I. Acid Orange 7 and phenol. The uptakes of these solutes were calculated from the concentration of unadsorbed solute estimated by colorimetry and atomic absorption spectrophotometry. C. I. Acid Orange 7 and Cu²⁺ uptakes (mol/10⁵ g) by AZ were 1.5-5.2 and 3.5-7.5, respectively. On the other hand Cu²⁺ uptake by TAZ was slightly less than that by AZ, but C. I. Acid Orange 7 uptake by TAZ was significant. Phenol was not adsorbed by AZ and TAZ. AZ may be effectively used as coagulating agent for anion ic dyes and Cu²⁺. It seems that TAZ is the superior adsorbent for anionic dyes.

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Novel organoantimony compounds of the type Sb (0SiR₃)₃ [2, R¹=R²=R³= Pr; 3, R¹=R²=R³=i-Pr; 4, R¹=R²= Me, R³ = t -Bu; 5, R¹=R²=R³= Ph] were prepared in 4 1 8 1% yields by the reaction of SbCl₃ with NaOiR₃ (3 molar amounts) in toluene. These compounds were characterized by IR, ¹H, ¹³C, and ²⁹Si-NMR, and MS spectroscopy. According to MS and NMR spectral data, each compound ap pears to be a monomer. They are subject to hydrolysis at room temperature. Thus, treatment of the com pounds 1-4 with a large excess of H₂O under slightly forced conditions resulted in the formation of the corresponding silanols and antimony trioxides. IR and XPD data suggest the resulting antimony trioxides have two polymorph; the first polymorph is senarmontite obtained by hydrolysis of the corn pounds 1-4 in H₂O/CH₃OH and the second polymorph is valentinite given by hydrolysis of 3 and 4 in H₂O/CH₃COCH₃.

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Toxic ozone emissions from corona discharge part of high speed copy machine have been increasing in recent years. Honeycomb-type catalytic supporter is used for such ozone decomposition. We prepared several kinds of cobalt catalysts supported on the honeycomb-type silica-alumina supports, which had the different pore structure in their walls, and investigated the effect of the pore structure on the ozone decomposition performances. Existence of the macro pore, in particular over 50μ m in pore diameter, resulted in an increase of the initial catalytic activity and a minor catalyst deactivation rate. Starch would be a very effective agent to form the above macro pore in the silica-alumina honeycomb-type supports.

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The titled chelate resin showed a good adsorption ability for Ca²⁺, Ba²⁺ and Sr²⁺ in the pH 8.0-10.0. The adsorption capacity of the titled chelating resin for Ba²⁺ was about 1.6 mmol/g-R on a dry resin. The rate of adsorption was high and adsorption equilibrium was attained with in 15 minutes. Ba²⁺ and Ca²⁺ or Ba²⁺ and Sr²⁺ loaded on the resin can be separated from each other by the elution with 1.0 mol⋅ dm^-3 CH₃COONH₄-20 vol% acetone solution, followed with 1.0 mol dm^-3 HCl.

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Synthesis of triisocyanatosilane (TIS) in a mixed solvent system of acetonitrile and benzene was investigated. The yield of TIS varied depending on the composition of the solvents. The reaction did not proceed in benzene, while it proceeded when acetonitrile was added to benzene. When 3 vol% of acetonitrile was added to benzene, TIS was isolated in 70% yield without any by-products. Tetraisocyanatosilane was a by-product when a great amount of sodium isocyanate or acetonitrile was used at higher termperature.

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Autoxidation of 5, 5'-biguaiazulene-3, 3'(5H, 5'H) -dione (2) was studied in CH₂Cl₂ an pyridine (or a mixture) at 25&deg; C for 24 h, giving preferentially 5-isopropylidene-3, 8-dimetyl-1 (5H) -azulenone (3)in CH₂Cl₂ and 3, 5-guaiazulenequinone (4) in pyridine as a major product. Compound 3 was converted into 3, 7-dimethy1-1-oxoindene-6-carbaldehyde (17, Y =95.1%), when the reddish-orange needles of 3 were allowed to stand at 25&deg; C for 7 d. Possible reaction pathways for the formation of these products are also discused.

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Single crystals of perovskite-type LuAlO₃ were successfully obtained for the first time in air at ambient pressure by a flux method using KF. Single crystals are transparent colorless or pale red cubes. Size of the cubes are 30-60 μ m in edge. This compound belongs to orthorhombic system, space group is Pbnm, lattice parameters are a= 5.103 (5) Å, b= 5.332 (5) Å, c= 7.305 (7) Å. Contamination from the flux reagent to the crystals is not observed.

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