Studies of clusters are important to understand the properties of clusters and chemical reactions in a condensed phase. Liquid ionization (LI) mass spectrometry provides informations about cluster ions produced at the surface of a liquid under atmospheric pressure and was applied to study of the cluster formation in carboxylic acid-water binary systems. Although the LI mass spectra were dependent to some extent on the experimental conditions, such as the acid concentration and the temperature of a sample, cluster ions represented as (R=CH, to CH3(CH02)3) acid-water binary systems. Some differences were observed in th e H+(RCOOH)77, (H20)(mostly m=1, ----8 and n=0-4) were observed commonly for mon ocarboxylic cluster ion distributions between m<4 and m>5. Besides, it is interesting to note that the anomaly abundant H+(RCOOF1)51-120 ions (referred to as 5-1 ion) were observed with very few 5-2 ions. These results strongly suggest that the 5-1 ions are stable and may have a ring structure composed of five acid molecules with one water molecule located inside the ring. Calculations were performed by the AM 1 method inplemented in MOPAC program packages. The optimized structure with the lowest heat of formation as far as examined, has the ring structure composed of five carboxyl groups connected with intermolecular hydrogen bonds. Alkyl groups are directed outward the ring and one oxonium ion is attached to slightly above the center of the ring. Hydrogen bonds play very important role to form clusters. Agreements between the observations and the calculations indicate that LI mass spectrometry is useful for studies of cluster ions and a liquid phase.

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Catalytic reduction of low concentration NO (10 ppm) with NH3 (20 ppm) was studied at the ambient temperatures (0-50 °C) over pitch based active carbon fiber (ACF) further activated with sulfuric acid. A fiber of the lowest surface area among the ACFs showed a significant activity in dry air, providing NO (10 ppm) conversion of 59% with 20 ppm NH3at 10 °C by WIF=5x 10-8 gmin/m/. Humidity in the air decreased very severely the activity, the lower reaction temperaure emphasizing the retardation, although non-trivial activity (NO conversion, 13 and 2% respectively) was still observed even at 22 and 0 °C under 100%humidity. Large WIF increased the conversion according to the first order kinetics. A slight heating up of the wet feed gas was very effective to increase the conversion comparable to that in dry air by decreasing the relative humidity at the reaction temperature. Humidity was found to severely reduce the adsorption of NO, the adsorption of NH3 being slightly influenced. The catalysis at 20 °C appeared to follow the Langmuir equation in a concentration range of 10 to 400 ppm of the reactant gases in both dry and wet air where the reaction order in NO was always first regardless of its concentration, while that in NH3 varied from first to zero, reflecting its concentration. The catalytic activities of ACFs and their further activated forms under variable conditions were correlated to the amount of evolved CO, at a temperature range of 200-450 °C in Temperature Programmed Decomposition Analyses. Two separate lines were obtained with the activities in wet and dry air, suggesting that the CO, giving acidic site on the ACFs is a common active site for the catalysis regardless of humidity, which reduces the effective number of the site through retarding the adsorption of both reactants. Polar ammonia may suffer less retardation of its adsorption by humidity.

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Absorption of nitrogen oxides (NO, ) is one of the NO removing processes. The absorption behavior of nitrogen monoxide (NO) with some oxide compounds was studied. NO, removal of employed four samples which were Y-Sr-Co-O, Y-Sr-Mn-O, Y-Sr-V-O, Y-Ba-Co-O compounds, were investigated. The NO removal meant (a reduced values of NO after reaction/a reactant NO values) x 100 at the point after 30 min reaction, when the N2 gas including NO 300 ppm, 02 3% pass thorugh 3 cm' sample oxides at flow rate 1000 m//mm. Then Y-Sr-Co-O oxide compounds indicated highest activity, ca, 100% for NO removal at 300 °C among the employed samples shown in Fig.1. When Y-Sr-Co-O was saturated by NO at 300 °C reaction, the amount of NO absorbed was 1.55 mol per 1 mol sample, and it clearly absorbed in the bulk. The absorption of NO by Y-Sr-Co-O occurred only in oxidizing atmosphere, and it was found that NO was oxidized to NO3- and absorbed by the oxide compounds because NO, - signals could be seen in FT-IR spectra (Fig.6). Y-Sr-Co-O included Co304 and Y203 crystals and ABO3 type perovskite consisting of Y, Sr, Co and 0. Since Co304 and Y203 crystals didn't absorb NO and the ABO3 type perovskite disappeared after NO absorption, the ABO3 type perovskite in Y-Sr-Co-O might be absorbing NO. It was found that Y-Sr-Co-O had active oxygen in compounds which was desorbed from sample at about 500 °C in TPD spectra. It implied that these active oxygen help NO oxidation and absorption. We suggested the schematic diagrams in Fig.8 for NO absorption of Y-Sr-Co-0.

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Hexaboron monoxide (B80) was prepared by the reaction of other oxides such as ZnO, CuO, 1n203, MgO, Bi208, Ga203 or Li2B4O7 and amorphous boron powders as starting materials in the range 1200 to 1450 °C for 2 h under an argon atmosphere. B60 powders were obtained from the strarting materials with the weighted-in atomic ratio boron/oxygen =6. O. The powders were examined by X-ray diffraction measurements. W hen starting materials were amorphous boron and 1n203, ZnO or Li2B407, the strongest relative X-ray diffraction intensities were obtained. The influence of reaction temperature on the formation of B80 phase began at 1300 °C in 1n203-B mixtures. The B60 phase formation from ZnO-B or Li2B407-13m ixtures began at above 1200°C. The B80 powders obtained from 1n203-B and ZnO-B mixtures had a reddish brown colour, and those from Li2B407-B mixtures had a black color. The lattice constants of the hexaboron monoxide are as follows: from 1n203a=5.340( 2 )A, c=12.3 50( 3 ) A, V=305.0( 2 ) A3----a=5.3 46( 3 ) A, c--=123.3 1( 3 ) A, V: 7-305.2( )A8; f rom ZnO: a =5.361( 2 ) A, c=12.348( 2 ) 1i, V=.307.3( 1 )A.8, --a-75.364( 2 ) A, c=12.3 33( 3 ) A, V=307.3( 2 ) Aa; from Li2B407: a=5.303( 2 )A, c=12.311( 3 ) A, V=299.8( 2 ). A.3320( 2 ) A., c=12.366( 3 ) 11, V=303.1( 2 ) 2U.

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A simple and highly effective pre-concentration method for a graphite furnace atomic absorption spectrometry of trace cobalt which involves the filtration of an ion pair of cobalt Nitroso R and a quarternary ammonium ion on an organic solvent soluble membrane filter followed by the redissolution using small volume of dimethylformamide is described. The optimum pre-concentration conditions were examined. The highest recovery was obtained by using benzyldimethyl (tetradecyl) ammonium for counter ion. The mechanism of the collection of the ion pair on the membrane filter was also discussed. The recommended procedure is as follows. To 1 dm' of sample containing 0-1 pg of cobalt(II), 1 cm3 of 0.02moldm-8 nitroso R solution and phosphate buffer, pH 8, are added, and after 3 min, 15 c m 3benzyldimethyl (tetradecyl) ammonium chloride solution is added. After 1 min, the solution is filtered by membrane filter (cellulose nitrate, diameter; 47 mm, pore size; 1 pm). The membrane filter is dissolved in 2 cm3 or 5 cm3 of DMF.20 mma of the solution is transfered to the graphite furnace of AAS and cobalt is determined at 2=-240.7 nm. The concentration factor (CF) was achieved 200-500. When CF was 200, RSD was 2.9%(n=5) and the sensitivity (=2 x SD) was 10 ppt and when CF was 500, RSD was 6.0% (n=5) and the sensitivity was 5 ppt. An application of the method for cobalt in river water was also descsribed.

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Various kinds of alkyl phenylcarbamates (Substituents in phenyl ring =3-i-Pr, 4-i-Pr, 3-isopropenyl, 2-OH, 3-OH, 4-OH, 4-(p-chlorophenoxy), 2-Me-5-i-Pr, and 2, 6-(i-Pr)2)were prepared by the reaction of anilines with chloroformates. Their biological activities were investigated. The compounds with 3-isopropyl group in phenyl ring were found to be active in herbicidal action to weeds and the cyclohexyl ester was the most active amoung them. The compounds with 3-OH group in phenyl ring were also found to be active in hypnotics. S-Alkyl phenylthiocarbamates (Alky1=Et, Pr, i-Pr, Bu, i-Bu, and s-Bu; substituents in phenyl ring = H, 3-Me, 4-Me, 4-Me(); 3-i-Pr, 3-i-PrO, 3-isopropenyl, 2, 6-(i-Pr)2, 4-OH, 4-C1, and 4-NO2) were prepared mainly by the reaction of anilines with carbonyl sulfid e and alkyl bromides in the presence of BuLi and their herbicidal activity was investigated. All the compounds were found to have herbicidal activities to weeds and the compounds with 3-isopropyl group in phenyl ring were the most active.727

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The direct photolysis of the title hydroxylamine (NT, 1) in protic polar solvents gives rearrangement (2, 3) and fragmentation (4, 5) products (Scheme 1). On raising the solventviscosity, the quantum yields for the disappearance of NT(0_, ) and for the appearance of 3-5 (q3_5) decrease, whereas the quantum yield for the formation of 2 (02) increases (Table 1). The finding that 02 and 0, clearly exhibit different solvent-viscosity dependence allows us to propose that rearrangment products 2 and 3 are formed by recombination reactions of singlet contact and solvent-separated radical pairs, respectively. A quantitative analysis of the reaction kinetics reveals that the extent of viscosity dependence of the rate for formation of a solvent-separated radical pair is a key factor governing the viscosity dependence of &NT and 02_5. On the other hand, the formation of a strong hydrogen bond between the amide carbonyl oxygen in NT and the hydroxyl hydrogen in methanol results not only in enhancement of the reactivity of singlet NT but also in acceleration of the production of a singletexciplex intermediate involved in the pyrene-sensitized reaction of NT.

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Seven analogues of angiotensin II, in which the N-terminal residue is commonly sarcosine were chemically synthesized in the liquid phase. The activity of those analogues as antagonist against increasing of blood pressure by angiotensin IL was measured for rats. Their 'H-NMR spectra in D20 solutions were measured at 200 MHz to know the relation between the activity and conformation or mobility of the molecules. The assignment of the observed peaks was made with spin decoupling measurements. The half-band widths of His6 e-CH were found to spread from 5 to 29 Hz, among which the two inactive analogues as antagonist were found to have the smallest band widths below 10 Hz. These results show that the imidazole ring of His is immobilized in some state in the conformation of active analogues.

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Poly(oxy-1, 4-phenyleneoxy-1, 4-phenyleneiminoterephthaloylimino-1, 4-phenylene) (PBTA)was prepared by low-temperature solution polycondensation of 1, 4-Bis(p-aminoxy)benzene with terephthaloyl dichloride in the presence of lithium carbonate as the acid acceptor in N-methyl-2-pyrrolidone. The value of inherent viscosity of PB-TA was 1.41 dllg in sulfuric acid (0.5% conc., 25 °C). In order to enhance tensile properties of PB-TA films cast from hexarnethylphosphoric triamide solutions, the films were drawn and heat-treated under various conditions. The tensile properties of PB-TA films were compared with those of poly(oxy-1, 4-phenyleneiminoterephthaloylimino1, 4-phenylene) (P-1), poly(oxy-1, 4-phenylenecarbonylimino-1, 4phenyleneiminocarbonyl-1, 4-phenylene) (P-2), poly[oxy-1, 4-phenylenecarbonylimino(chloro1, 4-phenylene)iminocarbony1-1, 4-phenylene] (P-3), and poly(oxy-1, 4-phenyleneiminocarbony1, 4-phenylenoxy-1, 4-phenylenecarbonylimino-1, 4-phenylene) (P-4) films which have similar structures to PB-TA. It was difficult to en hance the tensile properties of PB-TA films by cold and heat drawing at a constant temperature. Therefore, the films were drawn in an N, N-dimethylacetamide containing 2 wt% lithium chloride/water mixture (80: 20, v/v, 70 °C) and then were heattreated (temperature was raised from room temp. to 250 °C at the heating rate of 12 °C/min). The values of birefringence, strength at break, tensile modulus, elongation, and breaking energy of the drawn and heat-treated PB-TA films (sample 5 in Table 1) were 476 x 10-8, 540 MPa, 5.9%, 21 MPa, 34 M Jrn-8, respectively. The values of strength at break, t ensile modulus, and breaking energy of the sample 5were changed into 420 MPa, 13 GPa, and 29 M Jm-8 after 2 h of heat aging at 300 °C in air. These results showed the high-temperature durability of the drawn and heat-treated materials.

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The changes of the surface properties of graphite powders with direct fluorination was investigated by measuring dispersion stability, water adsorption, and zeta potential. The state of the fluorine atoms on the graphite surfaces was also examined by XPS analysis. The dispersion stability of graphite powders in water largely increased by the sur face fluorination. The fluorinated graphite particles in water were not flocculated and were dispersed stably for long time. The water adsorption an d zeta potential examinations showed that the surface fluorination provided more hydrophilic graphite particles, leading to the dispersion stability. The hydrophilic surface comes from introduction of the ionized fluorine atoms according to the XPS analysis.

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Macroreticular chelating resins containing amidoxime groups were prepared from styrene(divinyl-type compound) copolymer beads. Divinylbenzene and ethylene dimethacrylate were used as divinylmonomer. The chelating resins (RSNH and RSGNH) with various pore structures were prepared by changing the monomer ratio of each monomer in feed and the amount of diluent. The adsorption ability of the resins for Ag+, Cu2+, and UO22+ was investigated. The adsorption of CO+ and UO22+ was greatly affected by the pore structure of the resins. The good chelating resin (RSNH) was prepared from the macroreticular copolymer which was obtained by suspension polymerization of styrene (83 mol%), divinylbenzene (10 mole%), and ethylvinylbenzene (7 mole%), in the presence of 2, 2, 4-trimethylpentane (100 volume% per the monomer mixture) as diluent. The decreasing order of adsorption rate of RSNH for Ag+, Cu2+, and UO22+ is as follows: Ag+ >Cu2+ >UO22+. It was also found that RSNH had a high acid-resistance. The adsorption rate of the resins (RSGNH) with ethylene dimethacrylate as hydrophilic crosslinking reagent for metal ions was faster than that of the resins (RSNH) prepared from styrene-divinylbenzene copolymer beads.

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A gas chromatographic (GC) method for the simultaneous determination of mono-, di-, and triphenyltin compounds at ng// (ppt) levels in seawater is described. These compounds in seawater were simultaneously extracted into dichloromethane as their hydrides, such as monophenyltin trihydride (MPTH), diphenyltin dihydride (DPTH) and triphenyltin hydride (TPTH), converted by sodium borohydride and analyzed by GC with flame photometric detection (GC-FPD). The recoveries of monophenyltin trichloride (MPTC), diphenyltin dichloride (DPTC) and triphenyltin chloride (TPTC) from seawater sample were 75.0-82.4%, 79.4--92.6% and 84.5--91.5%, respectively. The detection limits for this method were 5 ng// for MPTC, 5 ng/l for DPTC and 20 ng// for TPTC. The concentrations of MPTC, DPTC and TPTC in seawater samples collected from Maizuru Bay, Kyoto Prefecture, for a period of one year from June 1989 to June 1990 were found to be N. D. (not detected). t Studies on the Determination of Trace Amounts of Organotin Compounds in Seawat e r and the Behavior of their Compounds in the Marine Environment. X.

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One of the most urgent tasks facing in the coke and by-product industry is improvement of the crystalline ammonium sulfate. It has been desirable that the crystal morphology of ammonium sulfate is cubic-like, rice grain-like or sphere form. A method was developed for the granulation of ammoniu m sulfate crystal by using some admixtures. The effect of admixtures (31 compounds) were examined by determining the crystal form. The effective admixtures are summerized as follows. (1) Reducing agents: sulfides, dithionite, ascorbic acid, etc. ( 2 ) Chelating agents: ethylenediaminetetraacetic acid (E DTA), nitrilotriacetic acid, polyphosphates, oxalic acid, etc. ( 3 ) Compounds, which m ake double salt combined with ammonium sulfate: amidosulfuric acid. It was found that the combination of amidosulfuric acid with reducing agents or with chelating agents are very effective for granulation and production of cubic-like ammonium sulfate crystal.

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Effects of heat treatment on IR spectra and b-axis values for various M3+, M2+, M+exchanged fluorine micas were investigated. The Si-0 stretching band frequencies and b-axis values changed on heating for the exchanged micas having smaller interlayer cation such as A13+, Ni2+, etc, whereas those didn't change for the exchanged micas having large cations such as Ba2+, K+ and Cs+. The wavenumber of Si-0 stretching band for the exchanged micas heated at 550 °C increased in the order of A13+>Ga3+>Fe3+>Ni2+>Co2+>Mn2+-exchanged micas, corresponding to the order of ionic rad ius of interlayer cation. The b-axis values of the exchanged micas heated at 500 °C are closely related to the ionic radius of interlayer cation, indicating that the smaller cation can migrate more deeply into the hexagonal hole and extend it during heating. The swelling ability of exchanged fluorine mica were decreased by heating, which can be explained by the degree of migration of interlayer cation.

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Experiments were carried out for the adsorption of aqueous chloroform onto activated carbon in a batch tank. An examination was then made on the parameter values obtainable from the measured adsorbate bulk concentration time data. Various approximate solutions gave values of the two parameters, adsorption equilibrium constant (Henry type) and surface diffusivity, while an exact solution failed to give values of these parameters. The exact solution only showed a relationship between possible values of the equilibrium constant and surface diffusivity: With the adsorption equilibrium constant value measured from a separate experiment the surface diffusivity value was estimated. Although these two parameter values are close to those obtained from a slight modification of Do and Mayfield approximation, it is recommended to carry out a separate experiment to determine the adsorption equilibrium constant value.

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Chemical species in the melted rime were analyzed by analytical electron microscopy, in order to find the evidences of long-range transport of air pollutants from the cities of Asian continent. High concentrations of SO24- and NO, - were found in the solutions of melted rime. These solutions at same time showed very low pH (3.62 and 3.92). In addition, numbers of particles were found in the rime. The particles around 1 pm diameter were considered to be the combustion products of coal, whose concentration ratio of lead and zinic (Pb/Zn) were similar to that at Seoul, Korea. It is suggested that the particles in rime has been transported to Japan accompanied with acid pollutants by prevailing westerlies, and may be deposited on the top of Kyushu mountainous region, Japan.

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