Addition of La or Ba to automotive Pd 3-way catalyst has been found effective in improving the NO_x reduction activities of the catalyst. Effects of these additives on the catalytic activities and durability were compared using Pd/γ-alumina catalyst and the ones with La or Ba added, after aging in simulated exhaust gases at temperatures from 600 to 900 °C. Catalytic activities of the catalysts were measured in simulated exhaust gases by two methods, a function of temperature and a function of air/fuel. The aged catalysts were characterized by BET, XRD, TEM and IR spectroscopy. After the agings above 800 °C, the NO_x reduction activities of the Pd/Ba catalyst were found superior to those of the Pd/La catalyst under reducing conditions. Both the BET surface areas and the Pd particle size on the catalysts aged at 900 °C were almost the same between the Pd/La and the Pd/Ba catalysts. On the other hand, some of La and Ba reacted with the y-alumina to form LaAlO₃ and BaAl₂O₄, but the decrease in the amount of carbonate on the Pd/La catalyst was larger than that on the Pd/Ba catalyst. These results indicate that the Pd/Ba catalyst maintaines high NO_x reduction activity even after aging at high temperatures, because Ba was more difficult to react with γ-alumina than La.

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In order to synthesize pillared micas with controlled microporous properties, expandable Li⁺exchanged fluorine micas having different layer charges (x)[Li_xMg_3-x Li_xSi₄O₁₀F₂(x=0.5, 0.8)] were allowed to react with various polynuclear hydroxochromium (III) solutions having different OH/Cr ratios and aging conditions, and the effects of layer charge on formation and properties of chromia pillared fluorine micas were studied. When host mica crystals had larger layer charge (x=0.8), Cr(III) monomer and Cr(III)-oligomers such as dimer and trimer having smaller cross sectional area per a positive charge were selectively intercalated into the interlayer region of mica. On the other hand, when host micas had smaller layer charge (x=0.5), highly polymerized Cr(III)-species with larger cross sectional area were selectively intercalated. Furthermore, intercalated Cr species were not only dependent On layer charge but also the containing ratios of Cr(III)-ion species in solutions. When pillared micas having larger layer charge were heated at 200∼300 °C, micropores were formed, resulting in larger specific surface area and pore volume. However, the pillared micas with smaller layer charge, as the result of intercalated large polymers, had larger basal spacings and thermal stability than the ones having larger layer charge, exhibiting relatively larger surface area and pore volume at high temperatures.

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Water-soluble sodium hydroxycalix[n]arene-p-sulfonates (Na_n1_n, n=4, 6 and 8), which were prepared by introducing the sulfonic acid groups into the p-positions of the hydroxyl groups of calix[n]arenes, behaved as a metal ligand even in the acidic solution and formed slightly soluble metal complexes in water with rare earth-, alkali earth- and some other metal ions, such as zirconium (IV), hafnium (IV) and thorium (IV). The composition of the metal complexes with rare-earth metal ions (Ln³⁺) was found to be NaLnl₄⋅mH₂O (m=7-40), Ln₂l₆⋅mH₂O (m=17-40) and Ln₂H₂l₈⋅ mH₂O (m=14-35), respec-ti vely, by the elemental analyses and IR spectra. The effects of the molar ratio of the metal ion to the ligand and the presence of the coexisting anions in the reaction mixture upon the yield of the complex also supported the above composition and indicated that the metal ion in the complex is bound with sulfonate groups of the ligand molecule forming the sulfonate chelate like a salt in property. A series of alkali earth metal ions (M²⁺) such as Ca²⁺, Sr²⁺ and Ba²⁺ also formed metal complexes having the sim ilar molecular formulas, M₂l₄⋅ mH₂O (m=5-10), M₃l₆. mH₂O(m = 5-22) and M₄l₈⋅ mH₂O (m= 6-20), respectively. On the other hand, tetravalent metal ions such as Zr(IV), Hf(lV) and Th (IV) form ed the complexes in which both sulfonate groups attached at the upper rim and deprotonated hydroxyl groups attached at the lower rim of the ligand coordinated to a metal ion in the complex.

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Lactate oxidase, glutamate oxidase and glucose oxidase were co-immobilized in a membrane through the photoreaction a poly (vinyl alcohol) bearing styrylpiridinium group (PVA-SbQ). The co-immobilized enzymes membrane was placed on the Pt anode of an electrochemical detector. The enzymes membrane sensor thus prepared was incorporated with analytical column in HPLC. Lactic acid, glutamic acid and glucose in the sample employed reacted with lactate oxidase, glutamate oxidase and glucose ox-id ase, respectively, to produce hydrogen peroxide, and the product was monitored electrochemically. Th e sensitivity of this detection system was nearly 100-fold greater than when using differential refrac tive index detection. The lower detection limit of each analyte was ca.70 ng (S/N= 3). The use of specific enzymatic reaction and electrochemical detector could simplify the pretreatments of the sample used. This method was successfully applied for the determination of lactic acid, glutamic acid and glucose in wine, sake, sour milk and sarad dressing.

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Reactions of 2- (1-haloalkyl) oidranes (1) with ammonium thiocarbamate (2) have been investigated. (RS) -2-E (RS) -α-Bromobenzylloxirane (la) with N-phenethylthiocarbamic acid phenethylammonium salt (2a) in methanol gave a N-phenethylthiocarbamate derivative (3a). Then, (3a) was treated with phenethylamine in DMSO to provide trans-2-phenyl-3-thietanol (4a) stereospecifically. Several other 3-thietanols (4b-d, 7, 12) were synthesized from the 2- (1-haloalkyl) oxiranes (1b-d, 6, 10) by the same procedure. These results demonstrate that this procedure is effective for synthesis of 3thietanols employing (2) as a sulfur source of 3-thietanols. A plausible mechanism of the 3-thietanol formation is presented.

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Synthesis of N- (2, 4, 6-tribromophenyl)maleimide (TBPMI) from maleic anhydride (MAN) and 2, 4, 6-tribromoaniline (TBA) was investigated. Although N-phenylmaleamic acid (PMA) is really p repared by the reaction of aniline (ANL) and MAN, N- (2, 4, 6-tribromophenyl)malearnic. acid (TBPMA)was not obtained by attempted reaction of TBA with MAN even at higher temperature. NPhenylmaleimide (PMI) is produced with a high yield using orthophosphoric acid as catalyst. Unlikely TBPMI was synthesized with only a low yield under similar conditions. However, it was found that TBPMI can be prepared with a high yield in mesitylene under reflux conditions at 168 °C. According to energy calculations, it was considered that the highest energy barrier of the reaction to yield N-substituted maleimide from MAN and primary amine presents in the first step by which N-substituted maleamic acid is produced. Formation of TBPMA is difficult because ΔΔG of TBPMA is about 2.6 times larger than that of PMA. These results seem to consistent with the above mentioned experimental findings, and orthophosphoric acid was found to be the effective catalyst for production of TBPMA and TBPMI. TBPMI as slight grayish white powder having mp of 142 °C was obtained by extraction of impurities with water and methanol, and its structure was confirmed by ¹H-NMR and IR spectroscopies.

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DSC (differential scanning calorimetry) and X-ray diffraction have been used for study of retrogradation of waxy corn starch. DSC measurments were performed in the temperature ranges of-15 °C to 15°C and 30 °C to 100 °C. For a waxy corn starch solution, a sharp endothermic peak was detected at about 0 °C immediately after gelatinization, and no other endothermic peaks were confirmed. After the solution was retrograded, a re-gelatinization endothermic peak was observed, and the endothermic peak at 0 °C was separated into two peaks. This result and the endothermic peak which is observed in the re gelatinization process were related to each other, and these are regarded as a result of the retrogradation. For refrigerated samples at -18 °C, no endothemic peak to be attributed to retrogradation was detected even after 72 days. X-Ray powder diffraction of the material obtained from the retrograded waxy corn starch solution, by precipitating with acetone, indicated that the diffraction patterns can be attributed to a crystalline B-forms. While, the heat of re-gelatinizetion on the basis of dry starch was approximately constant, this fact suggests that the mechanism of retrogradation may not be influenced by the concentration of solution. From these results, we propose that the waxy corn starch molecular structure can be attributed to gelatinization and retrogradation.

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The change in the circular dichroism spectra induced by immersion of the membranes into the aqueous tryptophan solution was measured using the immobilized serum albumin membranes prepared by the Langmuir-Blodgett (LB) method and the entrapment method. The α-helix content of the albumin membranes prepared by the LB method was observed to decrease on the immersion of the membranes into 0.01 M _D-tryptophan solution, whereas the completely opposite tendency was observed when the albumin membranes prepared from the entrapment method were used. The change in the circular dichroism originates from the conformational change of the immobilized albumin membranes induced by the binding between the albumin and tryptophan on the membranes. It is considered that orientated albumin on the LB film of poly (α-amino acid) makes the different conformational responses to the tryptophan binding to the albumin compared to randomly located albumin in the immobilized albumin membranes prepared by the entrapment method, because albumin on the LB film of poly (α-amino acid) was observed to be orientated from focal laser scanning microscopic measurements.

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N, N'-Dimethylperylene-3, 4: 9, 10-tetracarboxylic diimide (Me-PTC) was vapor-deposited on an ITO glass, a poly (tetrafluoroethylene) (PTFE) -coated glass and a KBr substrate. The film deposited on an ITO glass was composed of randomly oriented crystallites. On the other hand, Me-PTC grew epitaxially on a PTFE-coated glass and a KBr substrate. The Me-PTC crystals deposited at 100 and 150 °C were oriented with respect to the substrate crystal in the following epitaxial relatins: [010] (001)_Me-PTC//[001] (100) P _TFE-15°C, [010] (001)_Me-PTC//[110] (001)_KBr-100°C, (102)_Me-PTC//(001)_KBr-150°C and [010]_Me-PTC//[110]_KBr-150°C=±15°. The photovoltaic properties of the Me-PTC films were investigated in the ITO/ Me-PTC/I₃^-, I^-/ Pt wet system. The current-voltage measurement in the dark indicated a rectifying behavior due to an n-type semiconduction of Me-PTC. Under illumination, anodic photocurrents were observed. However, photocurrents decreased gradually and cathodic photocurrents were observed finally. The conduction type of Me-PTC film changed from ntype to p-type by the doping of iodine in the solution. The photovoltaic parameters of the epitaxial films were 3 times larger than those of the randomly oriented films. It was very important to control not only the molecular orientation but also the grain size in order to enhance the photovoltaic properties of Me-PTC film.

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The airborne suspended particulate matter (SPM) in urban artificial space consists of many kinds of particles emitted from different sources. The air in these spaces seems to be polluted by SPM particles emitted from sources in these spaces and apart from these spaces. Specifying the emission source of SPM particle is an important subject for environmental hygiene. The composition of each SPM particle is directly related to its origin. The conventional source apportionment methods are based on the bulk chemical analysis. Bulk chemical analysis, however, cannot offer direct information about sources, because only an average composition of collected SPM particles is obtained from such analysis. In this study, we developed a novel approach to the source apportionment of SPM particles by the combination of the sampling by the personal air sampler, the measurement of SPM weight concentration by the Piezo-balance mass monitor, the individual analysis by electron probe microanalyzer and a kind of multivaliant cluster analysis, median cluster analysis, using composition of each particle. This method was applied to SPM particles collected at underground center, underground parking and the traffic route near the ventilation in these artificial spaces in Kyushu area. Three SPM samples were collected at different time on a day: morning, daytime and night. From the results, it was clear that ( i ) the air in these artificial spaces were polluted from the SPM particles emitted from these spaces and pollutants in outside atmosphere, ( ii ) the ventilating system in these artificial spaces had a large effect on the composition of SPM particles in the air in these spaces, (iii) the structure of artificial space and design of ventilating system are very important factors for the control of air pollution in artificial spaces. We concluded that the developed method is powerful for the source apportionment of airborne SPM particles of polluted urban atmosphere.

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The SN reactions of t-alkyl alcohols with 1-adamantyl methanesulfonate and amines (molar ratio 10/1/1) were carried out at 80 - 100 °C under a nitrogen atmosphere. The corresponding products were obtained in 59- 94% yields, i.e., 1-adamantyl t-butyl ether (90%), 1-adamantyl t-pentyl ether (86%), 1-admametl 1, 1-diethylpropyl ether (82%), 1-adamantyl 1, 1-dipropylbutyl ether (59%), 1-adamantyl, 1-adamantyl 1-methyl-1-phenylethyl ether (71%), 1-adamantyl 1, 1-dimethy1-2-propenyl ether (90%), and 1-adamantyl 1, 1-dimethyl-2-propynyl ether (94%). In spite of the steric hindrance of t-alkyl alcohol and 1-adamantyl substrate, the yields o f the ethers were good to excellent. However, 1-adamantyl iodide was much less reactive than 1-adamantyl methanesulfonate even under severe conditions. The electronic effect of the functional group of t-alkyl alcohol was also exhibited. The optimum reaction conditions were examined, and the reaction mechanism was proposed.

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In order to increase the conversion of methane in dehydrogenative coupling of methane using a thermal diffusion reactor, the effects of coexistent inert gas have been tested. Argon is chosen as a coexistent inert gas which induces the concentration of methane in the reaction zone of the reactor without altering the temperature gradient. The methane conversion increased with increasing the molar fraction of argon of feed gas, and the maximum yield of gaseous hydrocarbons (mainly ethylene and acetylene)was obtained when the molar fraction of argon was 30%.

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