The chemical fixation of CO₂ into organic compounds has drawn much attention as an alternative for reducing its emittion into atmosphere. Especially, its oxygen-retaining fixations are of great advantage over oxygeneliminating ones such as methanation in respect of the energy consumption and the usefulness of products. The author and his co-workers have found that ruthenium complexes such as rutheniumcarbonyl and ruthenium chloride catalyze the reaction of CO₂, amines and alkynes including acetylene (Scheme 1) to give vinyl carbamate derivatives (2, 3, 4, 7, 8). The similar reaction of primamines with acetylene (eq.5) gave 1, 3-dialkylurea derivatives (9) at lower temperatures than the reaction without catalysis which requires ca.180 °C.
Although the attempt of synthesizing carbob nates from CO₂, alkohol, and alkynes in the presence of ruthenium complex/ t-amine catalyst system was unsuccessful (eq.6), the previously known reaction of CO₂ with 2-propynols catalyzed by copper salts (eq.7) has been found to proceed at much lower temper ature and to give linear diesters of carbonic acid (11, 12) in addition to the previously synthesized cyclic carbonate (14c) using this catalytic system (Scheme 2). When sec-amines or prim-amine was used instead of t-amine, carbamates (16) or 2 (3H) -oxazolones (17) were formed respectively (Scheme 3). Furthermore, the presence of prim-alcohols has led to the formation of carbonates (18) in the reaction of 2propynols and CO₂ catalyzed by the combination of ruthenium complex and amine (Scheme 4).
The reaction mechanism for the addition of carbamic acid to alkynes may include the nucle ophilic attack of carbamate anion to alkyne which should be activated by coordinating to ruthenium (Scheme 5). The intramolecular addition of alkyl carbonate anion is postulated for the reaction of 2-propynols with CO₂( S cheme 6). The further reactions occur according to the active hydrogen compounds presen t in the reaction media.

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On the basis of the general rules to get propagators under the Rückel approximation, practical calculation methods for the quantum chemical quantities of the topological reference systems are proposed. Where a topological reference system is replaced by a corresponding tree conjugated system. Quantum chemical quantities of a topological reference system are obtained by calculating the Hückel molecular orbitals of a corresponding tree conjugated system. In order to get a corresponding tree conjugated system of a topological reference system, simple diagrammatical methods are proposed. For exercises, several quantum chemical quantities for some [n]-Hückel annulene, n= 3 to 10, are calculated.

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Adsorption amounts, obtained from the differences between initial and equilibrium concentrations roitin-6--sulfate and sodium carboxylatomethylcellulose by silica Micon FN from an aq, u oef- scohdoinudm ous solution of 0.9% NaCl exhibited negative values in the presence of poly (N -vinylpyrrolidone). Sur- face pore and interparticle void space due to the aggregation of Micon FN were responsible for the nega-ti ve adsorption. Water molecule could penetrate into them while polymer molecule could not owing t o it s large size, resulting in concentrating the polymer in the bulk phase during the adsorption. Three methods to estimate the void volume were theoretically and experimentally developed: (1) 2-steps dilution method, by determining the polymer concentration in the supernatants before and after diluti on with a known amount of the solvent;. (2) graphic method, through determining the negative slope of an isotherm of apparent/negative adsorption; and (3)Na⁺-activity method, by measuring the Na⁺-activity i n the presence of known amounts of a polymer and Micon FN. The void volumes (V_p), estimated through these 3 methods, coincided each other ( V_p = 2 - 6 ml/g of Micon FN). The true amounts of adsorption became positive after the correction by using V_p.

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It is becoming increasingly important to decompose chlorofluorocarbons(CFCs) whi chdestruct ozonelayer. Catalytic decomposition process is expected to be an effective method which can be operatedat lower temperatures if catalyst of highactivity and duabilityisdeveloped. CFC113 decomposition activitieswith H₂O by metal oxide catalysts were investigated. Amongthem, TiO₂cataly stshowed high activity for decomposition. Buttheactivitywasdecreased to 97% afte r2h. To maintain high actiVity, anothermetaloxide(WO₃, Zr0₂, Nb₂O₅)was added to TiO₂. High decomposition activity waskept by TiO₂-WO₃ catalyst for 2h. Measurement of acidamounts for these TiO₂-based catalysts showed that TiO₂-WO₃ catalyst has more acidity of H₀≤-5.6 than TiO₂ does. From these results, it was assumed that acidity of H₀≤-5.6 had durability against decomposition reaction of CFC and it has become clear that the CFC decomposition actiVity is closely related to the amount of acid sites over catalytic surface. Durability test for continuous decomposition of CFC1130 ver Ti0₂-WO₃catalyst was carried out and the conversion of CFC113 during 100 h was above 99.5%. It was shown that TiO₂-WO₃ catalyst had long durability against decomposition of CFC113.

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In recent years, much attention has been devoted to the synthesis of zeolites from fly ashes and their aAplpthlication for the adsorbents for ammonium ion concerning the effective usage of industrial waste. ogh it is well known that natural zeolites such as clinoptilolite and mordenite have very good ionexchangeability for NH₄⁺, the characteristics of zeolites synthesized from fly ashes have been little known. In this study, NH₄⁺-adsorption characteristics of zeolites synthesizedfrom fly ash were investigated.
Phillipsite, analcime and hydroxysodalite were synthesized by hydrothermal treatment of fly ash with NaOH solution, and the amount of NH₄⁺-adsorbed by these zeolites in ammonia solution was measured under various conditions. It was found that only phillipsite has very high ability for NH₄⁺-adsorption among these three kinds of zeolites. Analcime and hydroxysodalite have very poor ability for NH₄⁺-adsorption.
The amount of NH₄⁺-adsorption increased linearly with increasing the content of philli. p-site The amount of NH₄⁺-adsorbed by 100% phillipsite was estimated to be 3.5 mmol/g by extrapolation of the linear relationship of NH₄⁺-adsoebed vs. comtent of phillipsite. On the other hand, the amount of NH₄+-adsoebed by 100% moedenite or A-type zeolite, Which are known as very good adsorbents for ammonium ion, measured under the similar condition was was 2.6 mmol/g. Therefore, it is concluded that phillipsite has higher ability for NH₄⁺-adsorption than mordenite or A-type zeolite. The amount of NH₄⁺-adsorbed by phillipsite changed with pH of ammonia solution, and showed a maximum at pH=6.5∼9.0.

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A specific and sensitive high performance liquid chromatographic method using immobilized enzyme membrane electrode is described for the simultaneous determination of ethanol and glucose.
Photo cross-linked polymer (PVA-SbQ) membrane coimmobilized alcohol oxidase and glucose oxidase was attached on the platinum electrode in the flow cell. The flow cell with the immobilized enzyme membrane was positioned after the column in HPLC. Phosphate buffer solution (pH 7.0, 0.05 mol/dm³)was used as a mobile phase and was flowed at a rate of 0.8 ml/min. At first, glucose was eluted through the HPLC column at ca.12 min and enzymically oxidized to gluconolactone and hydrogen peroxide by glucose oxidase in the immobilized enzyme membrane. Next, ethanol was eluted from HPLC column at ca.14 m in and oxidized to acetaldehyde and hydrogen peroxide by alcohol oxidase at the same enzym e membrane. Finally, produced hydrogen peroxide was amperometrically detected by the electrochemical method. The minimum detectable amounts of the ethanol and glucose were found to be 30 ng and 50 ng, respectively. The combination of specific immobilized enzyme membrane and electrochemical method enabled to perform highly selective detection of ethanol and glucose. This method was successfully applied for the determination of ethanol and glucose in alcoholic beverages.

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The thermal decompositions of four kinds of guanidinium salts, such as guanidinium dihydrogenphosphate (1), diguanidinium hydrogenphosphate (2), diguanidinium carbonate (3), and guanidinium nitrate (4), were investigated. The thermal behaviors of these samples under a nitrogen atmosphere differ from one another. In GC/MS measurements of volatile products generated by the thermal decomposition for these samples, major fragment ions were confirmed as water, ammonia, isocyanic acid, and carbon dioxide. Further, from the mass spectrometry and IR analysis of volatile products for four kinds of samples, the formation of identical guanidine derivative during thermal decomposition process was confirmed in all cases. In IR analyses for residues of 1 and 2 heated to various temperatures, their spectra differed from each other until temperature raised at 300 °C. Above 300 °C, the infrared band of guanidinium ion completely disappeared and then the thermal products of both samples showed identical spectra. Above 500 °C, polymetaphosphates and diphosphorus pentaoxides were formed by the thermal decomposition and subsequently occurred condensation reactions. The kinetics were partially resolved and activation energies were estimated for the thermal decomposition of guanidinium phosphates. The highest value of activation energies for 1 and 2 were observed at weight loss of about 20%. We suggest that guanidinium phosphates decomposed through the formation of guanidine and urea derivatives, such as biguanide and amidinourea.

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Chiral N-monosubstituted benzamides (1a-f), derived from optically active amines and amino acids, caused ortho-lithiation with 2.2 molar amount of n-BuLi and TMEDA in THF at 0 °C. The resulting ortho-lithiated benzamides reacted with aldehydes to afford adducts (2a-f) as diastereoisomeric mix tures, which were converted into phthalides (3) on acidic hydrolysis in high yields. The reaction of benzamides derived from chiral amines with aldehydes exhibited low diastereoselectivity. The optical yields of 3 obtained by the cyclization of 2a-c were also low. The use of benzamides (1d-f) derived from chiral β-methoxy amines remarkably enhanced the diastereoselectivity of 2d-f and the optical yields of 3. The reaction of the dianion derived from (S)-(-)-N-[1-(methoxymethyl)-2-methylpropyl]benzamide (1e) with pentanal followed by the cyclization under acidic conditions produced (S)-(-)-3-butylphthalide, an essential oil of celery, with 78% ee.

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The regioselectivity in the reactions of monosubstituted p-benzoquinone (1) (substituent: a: OMe; b: F; c: Cl; d: COMe; e: COPh; f: COOMe; g: CN; h: Ph; i: p -0₂NC₆H₄, j;p-Me₂NC₆H₄) with N, Ndimethylaniline (2a), N, N-diethylaniline (2b), N, N-dimethyl-m-anisidine (2c) and N, N-diethyl-manisidine (2d) in acetic acid was studied by means of two semi-empirical molecular orbital methods (CNDO/2, MNDO). The regioselectivity found in cases of 1h-j could not be accounted by the LUMO coefficients calculated for neutral 1. On the other hand, those for protonated 1 agreed very well with experimental results except for 1c in which regioselectivity was low. Thus, the largest LUMO coefficients were found at C-5 in 1a and 1b, C-3 in 1d-g, and C-6 in 1h-j, respectively, they are in good agreement with the regioselectivities from experiments. In addition, the LUMO energy levels of 1 are lowered when protonated by acetic acid, which would make the interation easier with the HOMO of 2. It seems that those energy level falls in protonated 1 promote the reaction of 1 with 2.

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Several polysaccharides were employed as a molecule-sieving additive for the separation of biological macromolecules in capillary electrophoresis (CE). Especially, glucomannan with an average molecular weight of 3x10⁵∼2x10⁶ Da, prepared from the crude polysaccharide of Amorphophallus konjac, exhibited good resolution and reproducibility on separation of biological macromolecules. Under optimized conditions, restriction DNA fragments were separated into each size. Based on its migration time, estimation of fragment size of the several restriction digests was performed without internal stan dards. And an enzyme-hydrolysed glucomannan with low molecular weight was also applied to separate oligonucleotides in CE. Highly reproducible separation was achieved by refilling the capillay with fresh glucomannan solution in each analytical cycle.
We concluded that the glucomannan is a good alternative to the conventional sieving additives for CE, such as polyacrylamide and hydroxypropylmethylcellulose, and this method would be applied to molecular cloning of a gene, separation and analysis of DNA fragments generated by restriction enzyme digestion or produced by polymerase chain reaction.

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Optical properties of thin crystalline films (thickness 0.3-0.5 pm) of even-numbered saturated fatty acids having carbon numberes of 16-24, which were grown on glass substrates with vacuum-evaporated Cr thin films, have been studied in an attempt to apply these films to optical recording materials. The laser beam (wavelength 830 nm, diameter 1 iim) was irradiated on the thin films at a scan rate of 4 m/s. This irradiation formed recording portions in the thin film through the process of partial melting and recrystallization of the fatty acid. The recording portions revealed high optical contrast against the nonirradiated portions under crossed-Nicols polarizing microscope. The recording portions were erased by the heating treatment at the temperature just below the melting point of the fatty acid, or by the laser beam scanning (diameter 5, um, scan rate 50 mm/s). Polarizing microscopic observation, X-ray diffraction and FT-IR RAS (Reflection Absorption Spectroscopy) spectra have been employed to analyze the recording and erasing processes. No difference in the polymorphic form was detectable between the recorded and original portions. However, it was found that the long-chain axes of the fatty acid molecules in the crystals of the recorded portion are parallel to the film plane. This makes a contrast to the original crystalline films in which the long-chain axes are normal to the film plane. In addition, we have found the regular relationships in the crystallographic axes between the recorded and original portions, by carefully observing the polarization behavior of the recorded portions under varying intensity of the laser beam. The crystallographic axes of the recorded and original portions are in such a specific relation that the optical anisotropy of each portion is canceled out, giving the high optical contrast of the recorded portions.

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As reported in the preceding paper, a recording device with high optical contrast can be formed by high-speed irradiation of laser beam on thin crystalline films of long-chain fatty acids grown on glass substrates with vacuum-evaporated Cr thin films. This article describes molecular-level analysis of the recording process, using a model substance of palmitic acid. Polarized FT-IR spectra of the palmitic acid crystals of the recorded and original films were analyzed in a comparative manner. The irradiation of the laser beam induced the change in the orientation of the long-chain axis of the crystalline film through the process of partial melting and recrystallizaion. The long-chain axis orientation of the original film was normal to the film plane, while that of recrystallized portion was parallel. In more detail, the intensity changes of CH₂ scissoring and CH₂ stretching bands in IR spectra with varying polarization directions showed that the c-axis of unit cells in the recrystallized portions of the recorded film was parallel to the b-axis, and hence normal to the a-axis, of the original film. To confirm this, the crystal growth process occurring after the laser irradiation was observed with SEM. The small crystals grew on the surface of the recorded portions, whose crystallographic axes were arranged with respect to the original film in the same directional relations as those observed by the FT-IR analyses. Consequently, it was proved that the high optical contrast of the recorded portion under the crossed-Nicols polarization is caused by superimposed arrangement of two types of crystalline films, the original film and the recrystallized film, with the specific relations of the crystallographic axes. The optical anisotropy of each crystal film is canceled out by this arrangement.

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Thermally stimulated current (TSC) of metallophthalocyanine dispersed in polyester (PEs) resin was measured and the photoconduction mechanism was discussed in relation to the carrier trapping and detrapping processes. The relaxation current from the polarized resin and the TSC peaks due to carriers trapped on the eigenlevels by light irradiation were observed.
In the case of a TSC peak made up by the superpos ition of various trapping levels, it was shown that they can be estimated with a curve fitting method by the algebraic sum of several theoretical TSC curves. The magnitude of the TSC peak current strongly depends on the wavelength of irradiation light. The carrier trapping levels were estimated from the TSC results. The distribution of the trapping levels in (oxo) (phthalocyanato) titanium (IV) (TiO (pc)) /PEs systems was found to be influenced by the size, inter-particle distance and crystal form of the TiO(pc) particles. It was concluded that the trapping site were formed on the surface of the TiO(pc) particles and / or at the interface between TiO(pc) and PEs.

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Anti-microbial materials were prepared with thiosulfato -silver complex supported on silic a gel. Thwe emkrea terials neaded with resin, and the color difference value ΔE_ab^* of the surface against natural re sin was measured. The ΔE_ab^* values were improved with an increase of specific surface area, or a doefc preoarvseoe l oufm sieli gceacl a rriers. Heat-treatment for silica gel carriers was usef ul foro ifm thprovement e suppression of ΔE_ab^* values. It was suggested that the color changes of molded resins with anti-microbial materials were caused by oxidatio n of decomposition of the complexes with adsorbed water that was free from silica gel carriers by heat -treatment through molding process -treatment for silica gel carriers decreased the. Heat adsorbed water on the carriers. Then this decrease resulted in reduction of free water from the carriers, and also resulted in inhibition for color changing of th e resin.

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High purity a-quartz was prepared by calcination of silicon dioxide-triethylamine (3/2) at 1000 °C for 24 h in air.
Silico n dioxide-triethylamine (3/2) was obtained by the reaction of triethylamine and silicic acid in a tetrahydrofuran (THF) solution for 24 h at room temperature. The compound was confirmed to be 2(C₂H₅)₃N⋅3 SiO₂ by the elemental analysis, infrared specturm and the thermogravimetric analysis.
Impurity of sodium, potassum, iron and aluminium was not detected by atomic absorption analysys o f α-quartz synthesized, a no uranium as impurity was also detected by fluorescence analysis.
Reaction was considered as follows.
3H₄SiO₄+2 (C₂H₅)₃N→2(C₂H₅)₃N→3 SiO₂+6H₂O
2(C₂H₅)₃N→3 SiO₂+ 21_??_O₂→3 SiO₂₊ 12CO₂+15 H₂O+2NO₂

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Precipitation samples (snow) fallen before and after of a strong low pressure passings along south cMoast of Japan were collected at Joetsu city, Niigata, Japan. Dissolved ions such as Na⁺, K⁺, NH₄⁺, Mg²⁺, Ca²⁺, Cl^-, Br^-, NO₃^-, and SO₄^2- and pH value were analyzed. The concentration of nss-SO₄^2-and nss-Ca²⁺ were very low and that of NO₃^- was high before the low pressure passings when the air mass above the Pacific Ocean would be brought to Joetsu city. The concentration of nss-SO₄^2- and nssCa²⁺ increased and that of NO₃^- decreased after the passings when the air mass above the Japan sea would be brought. The pH value was 5.38 and 4.77 before and after passings, respectively. The d ecrease in pH value corresponded to the increase in nss-SO₄^2-

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The catalytic performance of silver-supported and -unsupported TiO₂-ZrO₂ catalysts for the selective reduction of NO, in the presence of oxygen, was investigated by using a fixed-bed flow reactor system. The addition of silver promoted the catalytic activity of TiO₂, Zr0₂ and TiO₂-ZrO₂ for NO reduction with propene. Compared with Ag/TiO₂ and Ag/ZrO₂, Ag/TiO₂-ZrO₂ could reduce NO into N₂ with more than 90% selectivity. Although the catalytic activity of Ag/TiO₂-ZrO₂ for NO reduction with propene was depressed by water vapor, enhancement of NO conversion by the presence of water vapor was observed when 2-propanol or acetone was used as the reductant.

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