The effects of surface acoustic waves (SAWs) and resonance oscillations generated on ferroelectric substrates, which have been studied in an attempt to design heterogeneous catalysts with artificially controllable functions, are summarized. A thin film catalyst was deposited on the propagation path of Rayleigh and shear horizontal leaky SAWs which were generated on ferroelectric LiNbO₃ and LiTaO₃ single crystals. The SAWs caused considerable increases in the activity of ethanol oxidation on Ag, Pd and Ni catalysts and CO oxidation on a Pd catalyst. The enhancement of the catalytic activity is associated with the electromechanical coupling coefficients of the ferroelectrics employed and with the surface states of the catalysts. While the SAWs were on, the activation energy and reaction orders varied significantly for the reactions on the oxidized catalytic surfaces, whereas much smaller changes occurred for the reduced surfaces. The effects of SAWs are discussed on the basis of lattice displacement at surface, the generation of electric fields, and interactions between the carriers in the catalysts and ultrasonic waves. For the resonance oscillations, a disc of polycrystalline Sr-doped lead zirconate titanate was employed as a substrate. For ethanol oxidation on Pd, the activity increased 140-460 fold at a resonance frequency, which is related to a large lattice distortion at the same frequency. Both SAWs and resonance oscillations are concluded to be useful for the development of catalysts with artificially controllable functions.

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We examined the effect of microbes on several polymer samples which were buried under bio-active soil for over 32 years. We found that low density polyethylene (LDPE) films degraded considerably un, der biotic action, while no evidence was obtained for the degradation of urea formaldehyde resin (UF), polystyrene (PS), and poly (vinyl chloride) (PVC). The part of LDPE which was in directly contact with soil was severely degraded and characterized by whitening. On the other hand, the part which was not in contact with soil was transparent. A distinct difference was observed in surface FT-IR spectra of the whitened and transparent parts. The main oxidation products observed for the clear parts are carboxylic acids and ketones, while for the whitened parts the carbonyl absorption bands considerably decreased and was supplemented by the increase of the absorption by the carbon-carbon double bonds. By comparing with the results of the bio-degradation of LDPE under a well controlled environments, we concluded that the degradation of the clear parts proceeds by the normal oxidative process, while the d egradation of the whitened parts was explained by the complex mechanism of the oxidative degradation and bio-degradation. Under the biotic conditions, it has been suggested that the scission of alkoxyl radicals may proceed via γ-scission mechanism to form vinyl groups and volatile products in addition to the normal β-scission mechanism.
Our results showed t hat even the high molecular weight LDPE is degradable to form low molecular weight products by a biotic oxidation process, if they were concealed under bio-active soil for several ten years. It was also shown that the formation of active oxidation sites is essential for the acceleration of the bio-degradation of LDPE.

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The topological reference systems of the polycyclic conjugated systems are the hypothetical reference systems for which construction of all substructural details of the systems, except the cycles, should be taken into account. General methods to get propagators under the Hückel approximation are presented for the topological reference systems of the polycyclic conjugated molecules with same atoms and with the bond alternation. This method enables us to discuss the influences of the bond alternation on the energy stabilization and chemical reactivity of the polycyclic conjugated systems. The topological reference systems of the Hückel annulene with same atoms and with bond alternation are examined. Some quantum chemical quantities (such as the total π electron energy, the total π electron density, the bond order, the self-atom polarizability, and the frontier electron density) of the Hückel annulene and its topological reference system are obtained in general formulae.

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Non-isothermal kinetics was theoretically re-examined to inspect 3 dogmas in previous non-isothermal kinetics;
1) Rate equation for the irreversible reaction under the non-isothermal or the isothermal process comes to simillar formula.
2) Reaction w hich can be pursued is a simple elementary reaction.
3) Non-isothermal process should be lineally conducted. These were proved by the sliding model which was modified the Katoh model. The rate equations for irreversible reaction under the cooling process and reversible reaction were contrived by the use of its model. On the basis of our non-isothermal kinetics, NMR measurement of the activation parameters under stepwise non-isothermal process was constructed;
1) Product concentration is approximat ed by the power of time t.
C_pr=a₀+a₁t+a₂t²+a₃t³
2) Reaction rate is contrived from differentiating above formula by t.
3) Temperature for stepwise-nonisothermal process is corrected.
4)Activation parameters are calcuiated from 1)∼3) and next formula.
for irreversible reaction
for reversible reaction (2nd order and 2nd order)

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Three types of SnO₂ films, screen printed (20 μm thick, A), sputtered (20-500 nm, B) and SnO₂sol-derived (0.6 μm, C), were found to have very different sensing properties to 5 ppm H₂S in air. Films A and B showed sluggish response at 200 °C, increasing the response rate with incresing temperature accompanied by significant losses in sensitivity. On the other hand, film C showed sharp response as well as high sensitivity at 200 °C. As revealed from pore size distribution measurements, both A and B possessed a significant volume of micropores (less than 3 nm in diameter) while C possessed only mesopores (10-20 nm). These facts suggest that the difficulty of gas diffusion inside micropores is responsible for the sluggish response of films A and B at 200 °C, and that the development of large uniform mesopores leads to excellent H₂S sensing characteristics of film C. Even with film C, however, the response was degraded to a lower intermediate concentration range of H₂S (typically 0.1-1 ppm), suggesting that the gas diffusion inside mesopores becomes rate determining in that range.

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The reactions of methane and carbon dioxide over the catalysts based on the perovskite structual oxide, LaFeO₃, were examined. The reactions were carried out at 923∼1073 K and the conversions of methane and carbon dioxode attained to 10∼27% and 12∼46%, respectively, producing CO, H₂ and H₂O. It was found that two reactions exhibited below occurred at the same time, CH₄ + 3CO₂→+4CO +2H₂O and CH₄+ CO₂→2CO +2H₂.
The catalysts substituted with alkali metal or alkali earth metal for a part of La or Fe in LaFeO₃ catalyst formed C₂ compounds (C₂H₆, C₂H₄). The substitution effect of alkali metals was superior to that of the catalysts substituted with alkali earth metals. When 30% of Fe was replaced with alkali metals (M) such as LaFe_0.7M_0.3O_3-δ, the highest selectivity to C₂ compounds was obtained. The relationship between acid, base properties of the catalysts and C₂ compounds selectivity was examined. The acidic surface on the catalyst produced mainly CO and H₂ and basic one promoted to the C₂ compounds selectivity. By the reaction of CH₄ only and the TPD (Temperature Programmed Desorption) measurements, it could be clarified that the oxygen on the LaFeO₃ catalyst was mobile and that on the catalysts substituted with alkali metal rather hardly moved. These facts will be related to the reaction activity and to the C₂ compounds selectivity. By comparison with the results of XPS the active species of oxygen (O-, O₂^2-) on the catalyst surface were supposed to enhance C₂ compounds selectivity.

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The relations among the composition of CO₂-derivedspecies, their IR. frequencies and surface basicrty were investigated for various alkali metal-doped MgO. The doped alkali metals induced the decrease of the intensity of the absorption of linear CO₂ and thest ructuralchange of carbonate species; from bidentate to unidentate . These results are discussed in relation with the change of acid-base propeties. (Δγ)-¹'s, recipracal wavenumber-difference af asymmetric and symmetric str. vib. of OCO of unidentate carbonate were in the order of Li-doped MgO > Na-doped MgO > K-doped MgO > non-doped MgO, in agreement with the order of basicity obtained from analysis of the TPD profies of CO₂.
Furthermore, a distinct effect of the addition of Li on promating the ratio of acetone / propene produced in the decomposition of 2-propanol supported this order of basicity. The surface composition of unidentate carbonate was thought to be a key parameter to evaluate surface basicity.

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The dependence of growth parameters (deposition temperature and gas composition) on the deposition rate of tungsten nitrides on a qualtz substrate was studied by chemical vapor deposition (CVD) at temperatures of 500 to 803 °C under total pressure of 0.12-0.17 kPa, total flow rate of 60 ml/min in a gas mixture of WCl₆-NH₃-H₂ (in Ar). The mechanism of the deposition of tungsten nitride film with time on stream was also discussed. The tungsten nitride films were analyzed by scanning electron microscopy, X-Ray diffraction, and X-Ray photoelectron spectroscopy. W₂N (200) plane was preferably deposited for thickness of 0.5 μm, but W₂N (111) plane was mainly orientated above thickness of 1 μm. The thin film was smoothly deposited about 500 °C and has a fine structure without defects such as cracks and tearings. The reaction orders for W₂N deposition were 0.4, 0.3, and 0.3 with respect to WCl₆, NH₃, and H₂, respectively.

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Dehydration and ring closure of N-phenylmaleamic acid (PMA) to N-phenylmaleimide (PMI) in oxylene was investigated. A temperature-time plot showing a curvature was found to be divided into two parts, and the inflection point was observed at the boundary between these two parts. PMA crystals were dispersed in the organic solvent at the first half of the reaction time, and the organic phase became homogeneous at the latter half. The structure of ten types of compounds were separated from reaction mixture and identified by elemental analysis and IR, NMR, and GC/MS spectroscopies. Reactions yielding the identified compounds were proposed for the reaction stages. The following reactions are proposed for the first half of the reaction time.
1) PMI is produced by dehydration an d ring closure of PMA.
2) Hydrolysis of PMA yields maleic acid (MA) and anil ine (ANL).
3) PMI reacts with ANL to produce 2-anilino-N-phenylsuccinimide (APSI)
4) MA is dehydrated to be maleic anhydride (MAN).
5) Reaction of APSI with MAN leads to formation of N - (2, 5-dioxo-1-phenyl-3-pyrrolidinyl) -Nphenylmaleamic acid (PPMA).
6) MA isomerizes to fumaric acid (FA).
7) PMA also isomerizes to N-phenylfuma ramic acid (PFA)
During the latter half of the reaction, PPMA is mainly converted to PMI. The effects of the molar ratio of [MAN]/[ANL] and amount of catalyst on dehydration and ring-closure reactions of PMA were investigated. The reaction time of the first half increased with a decrease in the amount of catalyst, and the composition of the organic phase at the inflection point is almost constant. The amount of the catalyst influenced the degradation rate of PPMA at the latter half. APSI produced until the inflection point was converted to PPMA by adding MAN, and further reaction of PPMA to PMI after the inflection point improves the selectivity of PMI and increases the total yield of PMI.

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The possibility of new electrochemical model reaction of cytochrome P-450 utilizing proton as an activator instead of acid anhydrides was studied with voltammetry and controlled potential electrolysis. (5, 10, 15, 20-Tetraphenylporphinato) iron (III) chloride (Fe(TPP)Cl) was used as a metalloporphyrin and N-methylimidazole was used as an axial ligand. Cyclic voltammetric studies on the effect of orga nic acids, used as a proton source, on the electrochemical behavior of Fe(TPP)Cl suggested that electrocatalytic cycle shown in Scheme 1 seems to be operating. Oxidative demethylation of N, N-dimethylaniline was performed under potentiostatic condition at -0.23 V (vs.SCE) in ethanol solution containing acetic acid under air atmosphere. N-Methylaniline, the oxidized product, was formed in 70% faradaic yield.

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The thermal decomposition were studied for melamine cyanurate which was a very effective fire retardant for polyamide resins. The hydrogen bond distances increase with an increase in temperature. Some intermolecular hydrogen bond bridges of melamine cyanurate are broken at a temperature near 360 °C. At this temperature, melamine cyanurate do not always yield corresponding equimolar amounts of melamine and cyanuric acid. The pyrolysis of melamine cyanurate led to the formation of volatile or sublimate compounds such as ammonia, water, carbon dioxide, cyanic acid, melamine, and cyanuric acid. The resulting ammonium cyanate is due to the gas-phase reaction between ammonia and cyanic acid, and the deposited melamine cyanurate is also due to the gas-phase reaction between melamine and cyanuric acid sublimed. On the other hand, the residual melamine cyanurate condensed in the temperature range of 420 to 450 °C, and transformed to an material above 450 °C. The implications of thermal decomposition behavior for melamine cyanurate were discussed based on crystal structure and thermal decomposition products.

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A perfluorinated sulfonate cation exchange membrane was employed as a receiving sheet capable of developing color formers without any developing agent. The membranes treated with solutions containing one or two types of metallic ion such as Li⁺, Na⁺, Mg²⁺, and Ni²⁺ ions acted as developers for spiropyran, azomethine and diphenylmethane color formers. The effect of monovalent metallic ions as counter ions of the membranes on the developing ability was increased in the order of Li⁺ > Na⁺ > K⁺ ions according to the electronegativity of these metals. The same effect was observed in the case of divalent metallic ions, in which the effect was increased in the order of Ni²⁺ > Mg²⁺ > Ca2⁺ ions. In addition to the effect of these metallic ions, the developing ability of the membranes depended on the pH value of the treating solutions for the ion exchange, the water content of the membranes and the developing temperature of color formers. The dye forming reactions of these color formers with the membranes would be similar to the well-known reactions with acids.
The images so formed with the membranes were extremely stable and resistant to dark and light fadings, except for the light fastness of spiropyran dye.

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Rainwater was collected at two areas of Saga city in Saga plain field and Hokuzan in Sefuri mountains. It is about 20 km from Saga city to Hokuzan. Rainwater of the two sites were collected at the same time with every rainfall. The annual mean pH value of the rainwater of Hokuzan is higher than that of Saga city. The total ion equivalent in the rainwater of Hokuzan is about 1.2 times that of Saga city. Na + and Cl- derived from sea salt in rainwater of Hokuzan are from 2.7 to 6 time that of Saga city on the conditions of northern west wind or the typhoon. It is considered that rainwater of Hokuzan area is influenced by salinity of the Genkai Sea. The salinity of Genkai Sea is more than that of Ariake Sea. Concentrations of SO42-, NO3- and NH4+ in rainwater of Hokuzan station are much lower than those Saga city. t S tudies on Rainwater of Saga Prefecture. Ill.

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Potassium thiosulfatoargentate ( I ) have been used as anti-microbial materials. One of the complexes was grown as a single crystal in the solution composed of silver acetate and potassium thiosulfate (S₂O₃/ Ag = 6). The structure refinement suggests that the crystal is monoclinic system Kio[Ags (S₂O₃)8], and th e lattice dimension of the crystal is a=20.205, b= 11.267, c= 19.274, β= 108.49 deg. By means of powder X-ray diffraction analysis for the materials with the S₂O₃/Ag ratios of 2, 3 and 6, the materials have several unknown peaks at low angles, about 2θ= 10°, together with the peaks of the crystals K₂S₂O₃, K₂SO₃ and K₂SO₄. X-Ray diffraction peaks of the single crystal were calculated with the obtained d ata of th e single crystal lattice dimension; these calculated peaks were included in the peaks for the ab ove mentioned crystals. The complex Kio[Ags (S₂O₃)₈] should have the lowest solubility among th e crystals used as the anti-microbial materials in the thiosulfato complexes.

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The Grignard reaction of 10-bromo-7-methyldeca-2, 6-diene (5) with a C₂-symmetric chiral imide 1gave a corresponding hydroxy lactam 6 in 67% yield. Acid cyclization of 6 gave chiral carbocycles 7 and 8 in 53 and 15% yields, respectively. The stereochemistry of 8 was deduced by the NOE and CD spectra of the derived ketone 10. In a similar manner, the acid cyclization of the hydroxy lactam 12, prepared from the bromide 5 and a chiral imide 11, afforded a chiral carbocycle, which was purified as an acetate 13 in 27% yield. The stereochemistry of 13 was confirmed by correlating to that of 8.

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The reaction of guaiazulene (1) with a 1.3 molar amounts of an aldehyde reagent (i.e., acetaldehyde, benzaldehyde, glyoxal, glyoxylic acid, and furaldehyde) in acetic acid at room temperature (25 °C) for 1-4 h under argon readily gave the corresponding 3, 3'-methylenediguaiazulene having a substituent at C-ot position (2, 3, 4, 5, and 6, respectively) in good yield (83-98%). A rearrangement product, trans 4, 5-di- (3-guaiazuleny1)-2-cyclopenten-1-one (7), was also obtained as a minor product (8% yield) by the reaction of 1 with furaldehyde. The structures of these products were established on the basis of their spectroscopic (UV/VIS, MS, IR, and NMR) data. Possible reaction pathways for the formation of these compounds are discussed.

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Ytterbium and samarium-benzophenone complexes react with 1-alkynes to generate lanthanide. (II)acetylides having diphenylmethoxo ligand. It has been found that these acetylides act as reductants as well as nucleophiles, depending on the electrophiles used. Thus, their reaction with aldehydes and aliphatic ketones gives propargylic alcohols in good yields, while, with aromatic ketones and alkyl halide, the reductive coupling products are obtained selectively.

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Soluble fluoride ion in atmospheric deposits collected from Niigata Prefecture, located along the coast of the Sea of Japan, were determined. Soluble fluoride ion was a miner component in the atmospheric deposits. In the long term sampling stations, the averaged non-seasalt fluoride ion (nssF^-) concentration ranged from 0.56 to 0.63 μeg l^-1, while nssF^- deposition flux ranged from 2.43 to 3.91 μeg m^-2. d^-1. Seasonal variation of nssF^- concentrations and deposition fluxes showed a tendency similar to that of non-seasalt sulfate, which was higher in winter and lower in summer.

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