The interactions between cyclodextrins (CD) and hydrophobic normal tetraalkylammonium bromides in water were investigated by the conductance measurements at 25°. The conductance corrections based on the solution viscosities were made by Eq. ( 3 ). As shown in Fig.1, the corrected values of the equivalent conductances ( Λcorr) for tetramethyl-, tetraethyland tetrapropylammonium bromide in CD solutions agreed respectively with those in pure water, indicating that these salts had no significant interactions with CDs. However, the values of Λcorr for tetrabutyl- and tetrapentylammonium bromide in α-CD solutions were smaller than those in pure water, indicating that the formation of inclusion complexes took place in these systems. The formation constants evaluated by using Eq. (10) are shown in Table 1. The CDs enhanced the fluorescence intensities of 8-anilino-1-naphthalenesulfonate (ANS)in aqueous solutions (Fig.4). The formation constants of inclusion complexes were calculated from the fluorescence intensities by using Eq. (15). As shown in Table 2, the magnitude of the formation constants lies in the order of α- <β<γ- CD, indicating that anilinogroup of ANS were better accommodated in the cavity of γ-CD than in those of α- and β-CD. The salt effects on the complex formation between γ-CD and ANS were discussed in terms of the formation constants. Formation constants in 0.1 mol·dm-3 salts solutions were plotted against the values of (B_η - 0.0025 V⁰), where B_η and V⁰ were the viscosity B-coefficient and the partial molar volume of the cation, respectively. As shown in Fig.8, LiBr increased the formation constant, while the tetraalkylammonium bromides decreased it. These results were interpreted in terms of the structural interactions between the hydration cosphere of ANS and these cations.533

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Surface properties of hydrous titanium(IV) oxides (HTiO) precipitated from solutions of different pH (pH(prc)), 3 to 8.7, were investigated by means of two methods: nitrogen adsorption at -196° and fluoride ion adsorption. The precipitations were classified into two types BDDT 1V1p repared at pH below 6 and BDDT I at pH above 7. The pore structure changed from mesoporous to microporous with raising pH(prc). The most probable pore radius was about 2 nm for the precipitate prepared at pH(prc) below 5, 0.8 nm at pH(prc)6, and 0.44 nm at pH(prc) above 7, respectively. The surface area of the HTiO increased with raising pH(prc), while the pore volume and the surface density of hydroxyl group decreased. Comparing present data with those in literatures, it is suggested that the surface area of HTiO is strongly affected by the starting materials used and ionic impurities as well as the pH(prc).

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The electrofluorination of sulfur-containing compounds such as (NH₂)2CS, H₂NSO₃H, H₂NSO₃NH₄, CH₃CSNH₂ and NH₄SCN was studied in a molten KH₂F₃ at 120° by a few kinds of electrochemical methods. Amorphous carbon was used as the anode and Pt-rod as the reference electrode. Anodic products were analyzed by both gas chromatography and infrared spectroscopy. In the case of (NH₂)2CS, the anodic products were composed of N₂(+O₂), CF₄, NF₃, CO₂(+COF₂), SF6, N₂O, SO₂F₂, sulfur and a few unknown compounds. The critical current density (C. C. D. ) obtained by galvanostatic method was 400 mA ·cm^-2 in 0.4 mol% (NH₂)2CS. In contrast, the anode effect did not occur at the current density of 600 mA · cm^-2 in 4.0 mol%(NH₂)2CS, and the anode was often broken during electrolysis. In the case of H₂NSO₃H and H₂NSO₃NH₄, the anode gas was composed of N₂(+O₂), CF₄, CO₂, N₂O and SO₂F₂, and neither NF₃ nor SF6 was detected in the anode gas. The anode effect did not occur in 0.4mol% H₂NSO₃NH₄, and the anode was also broken during electrolysis at the current density of 3.4 mA·cm^-2 in 2.5 mol% H₂NSO₃NH₄. On the other hand, in the case of CH₃CSNH₂ and NH₄SCN, NF₃ or SF6 was detected in the anode gas besides N₂(+O₂), CF₄, CO₂, N₂O and SO₂F₂. A black or a yellow substance was observed at a surface of the fluoride melts besides these gaseous compounds. During electrolysis, the anode was not broken, but the gas outlet was closed with a black or a yellow solid substance. From these results, it is found that the starting material as the compound containing sulfur would prevent the atomic fluorine formed on the anode from the formation of (CF). n film, but that the carbon anode would be broken in the presence of both H₂O and sulfonyl fluoride such as SO₂F₂ in this melt. Mechanism of electrofluorination of (NH₂)2CS would be similar to that of (NH₂) 2CO as follows.

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Kinetics of the complexation of 2, 2'-(ethylenediimino)bis[(2-hydroxyphenyl)acetic acid](H₄ehpg or H₄L) with copper(II) ion (pH 2.4-2.9) and nickel(II) ion(pH 3.8-5.6), and the substitution reaction of the nickel(II)-complexes of ehpg with copper(II) ion (pH 5.0-5.6) have been studied in 0.1 mol%·dm^-3 NaClO4 at 20°. The observed rate constants suggest that the reactions of H₃L-, with Cu²⁺and Ni²⁺ contribute significantly to the CuH₂L. and NiH₂L, chelate formation and the reactions occur through the formation of the intermediate protonated complexes CuH₃L+ and NiH₃L+. The deprotonation of the intermediate complexes is the rate-determining step for the CuH₂L and NiH₂L chelate formation. From the Substitution reaction of the nickel(II)-complexes of ehpg with copper(II) ion, the rate constant for reaction of H₂L^2- with Ni²⁺ was evaluated to be (6.0+0.2) x 106 dm³·mol^-1·s^-1, which was larger than that expected from the Eigen-Tamm mechanism.

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This paper describes. Cd, Pb, Cu, Ni and Zn concentrations in the noted Quaternary Tephras in the Northern Kanto District. Thirty-five samples (including nine ones collected. from different zones at Minasawa) were well-known pumice-fall or pumice-flow deposits originated from Asama, Akagi, Haruna and Nantai volcano (Table 1). These were taken from some localities in Gunma (10 localities), Nagano (3 locs. ) and Tochigi Prefecture (4 locs. ). The samples were decomposed by acid digestion and analyzed by diethyldithiocarbamateisobutyl methyl ketone extraction-atomic absorption spectrometry.
Data show considerable concentration ranges of 0.28 to 0.77 ppm for Cd, 9.3 to 51.1 ppm for Pb, 2.0 to 60.8 ppm for Cu, 8.1 to 103 ppm for Ni and 17.3 to 124 ppm for Zn. The average concentrations of thirty-five samples were O.46 ppm for Cd, 22.8 ppm for Pb, 22.2 ppm for Cu, 41.2 ppm for Ni and 67.4 ppm for Znthe samples had some correlation between eiements. The Kanuma pumices from Akagi had noticeable low Cu, Ni and Zn concentrations as compared with another one from Akagi volcano and those from other volcanoes.

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A differential pulse polarographic method has been studied for the determination of molybdenum by use of the catalytic maximum wave. A well-defined differential pulse polarographic peak of molybdenum(VI) in 0.5 mol·dm^-3 acetic acid containing 0.1 rnmol·dm^-3α-hydroxy phenylacetic acid and 2 mmol·dm^-3 potassium bromate is observed in the potential range from O to -0.5 V vs. Ag/AgCl. The peak current is much larger than a diffusioncontrolled one, being proportional to the concentration of molybdenum(VI) between 5.0 ×10^-9and 5.0 × 10^-8 mol·dm^-3 under the good conditions. The relative standard deviation at 5.0 × 10-8 mol·dm^-3 molybdenum(VI) was 1.31% (n=7), the calculated detection limits being 8.49 × 10^-8 mol·dm^-3 (k=2, confidence level 97.2%). The method was applied to the determination of molybdenum in the stock feeds such as indian corn silage and orchard grass by the combined use of the column chromatography with a chelating resin. The chromatographic behavior of rhenium, tungsten and vanadium is similar to that of molybdenum(VI). However, 100-fold amount of these ions as mole ratio hardly interferes with determination, because the electrode reaction as to these ions is not sufficiently accelerated in the polarographic solution like molybdenum(II) is. The other common metal ions also do not interfere with the determination because of the pretreatment of the sample solution with the chelating resins.

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A method for the determination of submicrogram levels of fluoride by gas chromatography was developed. Fluoride ion is treated with trimethylchlorosilane (TMCS) in the acidified solution to form trimethylfluorosilane (TMFS), which can be extracted with a toluene solution containing 4.0 × 10^-3% isopentane as an internal standard. The extraction is done through the diffusion of TMFS into the toluene layer without shaking.
Take 100 mm³ of a sample solution containing 10-200 ng fluoride in a 1 cm³ reaction tube (8 mm i. d. ) with a ground glass stopper and insert a small glass rod (7 mm∅) into the tube quietly (Fig.1). Add 0.1 cm³of TMCS-saturated 9 mol/dm3 hydrochloric acid and 30 mm3 of the toluene solution. The stopper is sealed with concentrated phosphoric acid in place of vaseline. After standing overnight, set the tube on the vibrator (Fig.1-b) and vibrate gently for 1 minute to make the toluene layer uniform. Inject 1 mm3 portion of the extract into the gas chromatograph with a flame ionization detector. Calculate the peak height ratio of TMFS to isopentane from the chromatogram (Fig.2) and determine the amount of fluorine from the calibration curve (Fig.9). The GC conditions are as follows; column packing: 2% OV-3 on Uniport HP (80/100 mesh), column size: 2 m × 3 mm i. d., column temperature: 50°, injection temperature: 140°, carrier gas: N₂ 30 cm³/min.
Minimal detectable amount by the proposed method is I ng F. Most ions encountered in natural or environmental samples do not interfere (Table 2). Aluminum ion in 1000: 1 or silicate ion in 800: 1 weight ratios to fluoride can be tolerated. Several types of geothermal water samples were analysed for fluorine by the proposed method (Table 3). The results agreed well with those obtained by a fluoride ion-selective electrode method.

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For concentration of trace amounts of chromium(VI) in water, the adsorption of chromium (VI) on iron(III) hydroxide, bismuth(III) chloride oxide, bismuth(III) hydroxide oxide, bismuth(III) hydroxide, and mixed hydroxide of iron(III) and bismuth (VI) was studied. Chromium(VI) adsorption was found to increase in the following order; mixed hydroxide of iron(III) and bismuth(III)>bismuth(III) hydroxide oxide> iron(III) hydroxide > bismuth (III)hydroxide>bismutha(III) chloride oxide. The presence of chloride, nitrate, and sulfate suppressed the chromium(VI) adsorption to a greater extent on iron (III) hydroxide and to a lesser extent on mixed hydroxide of iron=and bismuth(III), and on bismuth(III) hydroxide oxide. Mixed hydroxide of iron(III) and bismuth (III), which was prepared by adding sodium hydroxide to a equimolar solution of iron(III) chloride and bismuth (III) chloride, was the most favorable for adsorbing chromium(VI) from synthetic sea water. A 0.5 ml portion of a mixture containing 1 mol/l each of iron(III) and bismuth (III) was sufficient for the complete adsorption of 0.1 mg chromium(VI) in 100 ml of synthetic seawater at pH 6.5.

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A series of 9-substituted 9-(2-methoxyphenyl)fluorene derivatives (9-bromo-[2], 9-methoxy[3a], 9-ethoxy-[3b], 9-hydro-[4], 9-methyl-[6a], 9-ethyl-[6b], 9-carboxy-[7], 9methoxycarbonyl-[8a], 9-ethoxycarbonyl-[8b], 9-acetyl-[9a], 9-benzoyl-[9b], 9-(4-bromobenzoy1)[9c], and 9-(4-methoxybenzoyl)-9-(2-methoxyphenyl)fluorene [9d] were prepared from 9-(2-methoxyphenyl)-9-fluorenol [1] as the starting material, and their conformationalequilibria between two conformers, sp and ap forms, caused by rotation around the C(9)-(2methoxyphenyl) single bond were investigated based on theσ values of methoxy group of 2-methoxyphenyl in their 'H-NMR spectra measured in CDCl3 at room temperature. The ap form was found to be predominant for the compounds [2], [3], and [6], and the sp form for the compounds [1], [4], [7], [8], and [9]. In the cases of [7], [8], and [9], it was assumed that a nonbonded intramolecular attractive interaction between methoxyl group and carbonyl group should contribute to stabilization of the sp form. Both rotational isomers (sp and ap) were observed only for [4] at a low temperature, and the ratio of the isomers was evaluated as sp/ap=17/1 at -55°C. The free energy value of activation ([ΔG]) for the process sp-[4] → ap-[4] and ap-[4]) →sp-[4] were found to be 13.1 kcal/mol and 11.3 kcal/mol, respectively.
Furthermore, it turned out that the conformation of [1] was affected by the solvents; the sp form was predominant in CDCl₃, but ap form in DMSO.

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Palladium-catalyzed reaction of diaryliodonium salts in the presence of zinc powder took place readily under mild conditions to give biaryls and aryl iodides almost quantitatively according to equation:
2 [Ar-I-Ar]X+ Zn →Pd-cat Ar-Ar+2Ar-1+ZnX₂
The most effective palladium species was [Pd(acac)₂] and activities Of the species decreased in the order: [Pd(acac)₂]>Pd(OAc)₂>[Pd(dba)₂]≥[PdCl₂(PPh₃)], Pd-black, PdCl₂ (Table 1), Metallic tin and copper were not so effective for selective formation of biphenyl (Table 2). Among various solvents used as the reaction medium, tetrahydrofuran was the most suitable one (Table 3). Under the optimum conditions of catalyst, reducing agent, and the reaction medium, the yields of biphenyl and iodobenzene were 96 and 99%, respectively. The reaction was applied to various kinds of substituted diphenyliodonium salts. The corresponding biaryls were formed in high yields (Table 4). In the reaction of unsymmetrical substrates such as arylphenyliodonium salts three kinds of coupling products, biphenyl, biaryl and phenylarene were obtained (Table 5). When the Hammett equation was applied to the distributions of the coupling products, the p-value was obtained as +0.4, and it was the nearly the same in other reactions of diaryliodonium salts. This suggests that the present reaction proceeds via two intermediates i. e. arylpalladium species and diaiyfpalladium species, and that the former intermediate determines the distribution of the coupling products. Transition Metal Catalyzed Reactions of Diaryliodonium Salts. IV.

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The palladium-catalyzed carbonylation of diaryliodonium salts has been investigated. In the presence of zinc and a catalytic amount of palladium compounds, diaryliodonium salts were easily carbonylated to give a mixture of mono and double carbonylation products namely diaryl ketones and diaryl a-diketones in good yields under mild conditions. Biaryls were also formed as a by-product.
2 [Ar-I-Ar]X + CO Zn →Pd-cat ArCOAr, ArCOCOAr+2ArI ZnX₂
Diphenyliodonium bromide was used for examination of various factors in the reaction. Catalytic activity of transition metals decreased in the order: Pd>Rh>Ni, and the activity of palladium species was in the order: Pd(OAc)>[Pd(acac)₂]>[Pd(dba)₂]>PdCl₂>[PdCl₂(PPh₃)₂]>Pd-black (Tablel). Zinc was the most effective reducing agent and other metals such as Sn and Cu were only slightly active (Table 2). Various kinds of solvents were satisfactory for the reaction, but in alcoholic solvents larger amounts of benzoates were formed (Table 3). Biphenyl appeared to be formed in preference to the carbonylation products at higher reaction temperature (Table 4). Increase of the carbon monoxide pressure brought about an increase of selectivity in the double carbonylation product (Table 5).
Diaryliodonium salts([Ar₂I]X:Ar=Ph-, 4-CH₃C₆H₄-, 4-t-C₄H₉C₆H₄-, 4-ClC₆H₄-, 4-BrC₆H₄-, X=Cl, Br, 1, BF₄)were effectively transformed to diaryl ketones (38-68%) and diaryl cx-diketones (4-20%) under the atmospheric carbon monoxide pressure with the palladium-zinc system. Effect of substituents on the reaction showed that the electron. withdrawing groups decreased the yields of the carbonylation products and the electrondonating groups increased them (Table 6).
The carbonylation is considered to proceed as follows. The initial oxidative addition of a diaryliodonium salt to palladium(0) yields the arylpalladium species. Disproportionation of the arylpalladium halide by zinc leads to the diarylpalladium species, which then reacts with carbon monoxide to form an acylarylpalladium and diacylpalladium compounds. The diaryl ketone and diaryl ex-diketone are formed by reductive elimination, respectively.

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Benzothiazole and its related compounds, which were chosen as model compounds for hydrodesulfurization and hydrodenitrogenation of heavy fuel oils, were hydrogenolyzed under the constant hydrogen pressure of 40 atm at 200-320° for 90 min with molybdenum(VI) sulfide as a catalyst.
Hydrogenolysis of benzothiazole (Table 1) yielded appreciable amounts of aniline and oand p-toluidine accompanied by small amounts of 2, 4- and 2, 6-dimethylaniline and 2, 4, 6-trimethylaniline. As intermediates, N-methylaniline and o-(methylthio)aniline were obtained at relatively low reaction temperature, while thioanisole, thiophenol and benzene were scarcely produced. In the hydrogenolysis of 2-methylbenzothiazole (Table 4), aniline, o- and pethylaniline, and 2, 4- and 2, 6-diethylaniline were obtained.
The hydrogenolyses of the related compounds of benzothiazole (Table 2) suggested that the bond cleavage between sulfur atom and carbon atom of benzene ring decreased in the following order: o-(methylthio)aniline > m-(methylthio)aniline ≈thioanisole o-aminothiophenol >>m-aminothiophenol≈thiophenol. The ortho amino group in o-(methylthio)aniline and o-aminothiophenol seems to promote this type of sulfur-carbon bond cleavage. It was suggested that the ring-alkylated anilines would result from the elctrophilic aromatic substitution of alkyl cation, which might be formed effectively on the catalytic surface through the thiazole ring cleavage.

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N-polyfluoroalkylations of amines and the potassium salts of phthalimide and benzenesulfonamide with the various polyfluoroalkyl o-nitrobenzenesulfonates [1a-b] were investi gated. The sulfonates ([la] and [1b]) having shorter polyfluoroalkyl groups reacted with primary, secondary, and cyclic secondary amines to afford the corresponding N-(polyfluoroalky)amines ([4]-[10]) in good yields (47-95%), while the reactions with the longer polyfluoroalkylsulfonates ([lc] and [1d]) gave mainly aromatic substitution products ([11]and [12]) in addition to the ordinary N-polyfluoroalkylation products. The reactions of polyfluoroalkyl p-toluenesulfonates [2] and iodides [3] with amines gave the poor results (Table 1). Although phthalimde and benzenesulfonamide did not react with [1], their potassium salts reacted with [1]to give the corresponding N-polyfluoroalkylation products ([14] and [16]) (Tables 3 and 4). In the reactions of potassium benzenesulfonamide, N, N-bis (polyfluoroalkyl)benzenesulfonamide [17] was also obtained. The reaction of potassium phthalimde with [3c] gave HF-elimination product [15] in addition to a small amount of [14c]. These results show that [1] is a much more useful agent for N-polyfluoroalkylation of amines and potassium phthalimde than [2] and [3].

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Hydrogen transfer reactions between ten kinds of hydroaromatic donor solvents and a stable free radical as a model radical fragment of coal, 2, 2-dipheny1-1-picrylhydrazyl, were investigated at mainly 60°C up to 100 MPa using a butchwise high pressure reactor. The kinetic results for seven kinds of donor solvent, as shown in Fig.1 as a typical example, were able to be analyzed statistically as third-order process, and the reaction rate constants were evaluated for each donor solvent. As a consequence, the order of the hydrogen mobilities of these donor solvents was as follows: 1, 2, 3, 4-tetrahydroquinoline >1, 2, 3, 4-tetrahydroisoquinoline >1, 4-dihydronaphthalene >1, 4-cyclohexadiene > 9, 10-dihydroanthracene > 1, 2, 3, 4, 5, 6, 7, 8, -octahydroanthracene> tetralin. The reaction rate constants increased about twice with increasing the pressure from atmospheric to 100 MPa, and these magnitudes were independent of the solvent properties under our experimental conditions. It might be concluded, therefore, that the sequence of reactivity is the same even at high pressures. The estimations of the rate constants for 1, 2-dihydronaphthalene, acenaphthene, and 1, 3 -cyclohexadiene were unsuccessful because of its complicate kinetic behavior as shown in Fig.2. However, the hydrogen transfers from the above three kinds of solvent were also accelerated with increasing pressure as a general tendency. In summary, the results suggest that homolytic hydrogen transfer is accelerated with pressure regardless of the nature of donor solvent and the application of high pressure on coal liquefaction process is advantageous from the viewpoint of the hydrogen transfer reaction. t Study on Coal Liquefaction. II

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Thermal Decomposition reactions of myrtenyl acetate C 1 D, myrtanyl acetate [2], verbenyl acetate C 3D, verbanyl acetate [4], pinocarvenyl acetate [5] and pinocamphenyl acetate [6]were carried out in ZnCl₂/KCl/NaCl fused salts (Chloride fused salts) or NaNO₂/NaNO₃/KNO₃ fused salts (Nitrate fused salts). The salt effects on the product distribution were examined. In the nitrate fused salts, myrcene C 9J and 4E, 6Z-alloocimene [13] were obtained as the principal components from [1]. Piperitenone [20] was obtained from [4] as the main product. The selectivity of this reaction amounted to 82% under the optimal conditions. Pinocarvone[25] was obtained as the principal component (78%) from [5]. The thermal decomposition of [6] predominantly gave pinocamphone [24]. In the chloride fused salts, [9] was obtained from [2] in the high selectivity (92%). Dihydromyrcene [4] was obtained as a main product from [3] and [4].5-Ethyl-1, 5-dimethyl-1, 3-cyclohexadiene [17] was obtained as the principal component from [6] in the 71% selectivity. t Studies on the Thermal Decomposition of Terpenes in Mixed fused Salts.

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The poly (vinyl alcohol) having both hydrophobic groups and hydrophilic groups has been prepared to endow water-solublity and interface activity. The modified poly(vinyl alcohol), derived from the terpolymer of hydrophobic monomer [Veova], hydrophilic monomer Maleic anhydride or itaconic acid, and vinyl acetate, was soluble in water and gave an aqueous solution of low interfacial tention. Its film had water repelling property.
The vinyl acetate emulsion using the poly(vinyl alcohol) as a stabilizer was "high viscosity-low thixotropicity-high stability". The observation indicates that the modified poly(vinyl alcohol) has characters of both fully saponified and partly saponified ordinary poly(vinyl alcohol). It is noteworthy that the paper coated with the poly(vinyl alcohol) gave excellent barrier properties such as oil absorptivity, air permeability and also high surface strength.

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The polymerization of methyl methacrylate (MMA) using vitamin 1312 (cyanocobalamin: BCN) was investigated as an example of the reactions of physiologically active substances in vitro. It has been found that the radical polymerization of MMA can be initiated by the combined system of BCN and reductants such as formic acid, oxalic acid, or 2-mercaptoethanol (MEE; only in the lower concentration). Kinetic studies of polymerization by systems BCNformic acid and BCN-MEE showed the rate (Rp) of the polymerization being approximately expressed by equation:
R_p=k[MMA][BCN]^4.5[HCO₂H or MEE]^0.5
The overall activation energies for the polymerization were estimated to be 12.2 kcal/mol (for formic acid system), 12.6 kcal/mol (for oxalic acid system), and 18.7 kcal/mol (for MEE system), respectively. The spectra of the BCN-reductants mixtures (in H₂O or CH₃OH)and the polymer obtained by these systems were also measured (Fig.7, 8, and 9). The kinetic study and spectral analysis suggest that the initiating radical is produced as a result of the redox reaction between BCN and the reductants (one electron transfer from the reductant to BCN).

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The catalytic activities of several natural zeolites including mordenite and clinoptilolite types in the polymerization of styrene were examined comparing with those of an acid clay and a synthetic zeolite (Y-type). The effects of preheating the zeolites on their catalytic activities were also examined in the range of 100-900°C. The natural zeolites were found to polymerize styrene and the mordenite types gave higher conversion (40-60%) than that of clinoptilolites (10-15%). The catalytic activity of the zeolites and the maximum conversion of monomer was observed at ca.600°C. The weight average molecular weight (Mw) of the resulting polymers was ca.2400-11000. The results obtained were discussed on the basis of acid strength of the zeolites.

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The concentrations of arsenic compounds in the atmosphere at trace levels were measured at various sites in Japan. The particulate arsenic was collected by two stage Andersen impactor, and the gaseous arsenic was collected by a filter impregnated with 10% poly(ethyleneimine)and glycerol solution. Arsenic compounds were analyzed by hydride generation atomic absorption spectrophotometry combined with a cold trap of liquid nitrogen for a trapping of arsines. This method has a high sensitivity and can determine organic and inorganic arsenic compounds separately.
It was concluded that more than 90% of arsenic in the atmosphere was inorganic particulate arsenic (0.38-9.7 ng As/m³), the rest were organic particulate arsenic (0.03-0.27 ng As/m3)and inorganic gaseous arsenic (0.006-0.09 ng As/m³). Most of the organic arsenic was dimethylarsinic acid (DMAA). Methylarsonic acid (MAA) and trimethylarsine (TMA) were not found in any sample. Organic gaseous arsenic was not found either.
Atmospheric concentration of organic arsenic (DMAA) increased in summer and decreased in winter. However, as for inorganic arsenic and gaseous arsenic, seasonal variation was not observed. Thus production of organic arsenic might be due to the methylation of inorganic arsenic through biological processes.
Size distribution of inorganic arsenic in the atmosphere was bimodal with two concentration peaks at 2 μm and 0.5 μm, and its mass medean aerodynamic diameter (MMAD) was 1.0 μm and most of inorganic arsenic existed as fine particles with diameters less than 2 μm. Size distribution of organic arsenic was quite predominant in fine particle with a concentration peak at 0.5 μm, and organic arsenic was not detected at coarse particle region exceeding 4 μm. It is considered that inorganic and organic arsenic compounds are emitted as gas to the air by burning oil and coal and by methylation of inorganic arsenic, and then condense to fine particles. Therefore, it suggests that size distributions of inorganic and organic arsenic in the atmosphere are mainly in fine particle.

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The marine aerosol was collected by Andersen sampler and two-stage filter sampler during January 13-20 and December 14-20, 1981 on the two remote islands, Hachijo-jima and Chichi-jima in order to investigate its size distribution and atmospheric concentration. The concentrations of Na+, Cl, NO₃^-, and SO₄^2-, in the marine aerosol were determined by ion chromatography. Sulfur dioxide in the marine atmosphere was collected with an alkali filter and also measured by ion chromatography. The size distributions of Na⁺ and Cl^-in the marine aerosol had coarse mode and their modal diameter were 3-5, μm (Fig.1). More than 85% of total Na ⁺ and Cl^- existed in coarse particles (>2, μm), which presμmably originated from sea spray. The nitrate particle in the marine atmosphere was almost coarse and was different from the submicron nitrate usually observed in the urban air (Fig.2), indicating that the reaction between sea salt particles and HNO₃ vapor occured in the marine atmosphere. The size distribution of sulfate was bimodal, suggesting that coarse sulfate particles (>2, μm) were derived from sea spray and fine sulfate particle (<2 pm) were transported from polluted area (Fig.2). The concentrations of nitrate, fine sulfate, and sulfur dioxide in marine atmosphere in Chichi-jima islands, 1000 km remote from Japan, were 0.14, 0.36, and 0.20 pg/rn3, respectively. These concentrations were concluded to be background levels in the marine atmosphere since they were 1/10-1/100 times lower than those in polluted Yokohama area. However these pollutant concentrations in the winter when the north-west seasonal wind blew were 2-4 times higher than the above background levels, and the migration of pollutants from the Japan islands to Chichi-jima was observed.

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The running costs of the deodorant plant by catalytic combustion can be decreased if the designer makes the best use of combustion reaction rate parameters. The purpose of this study is to determine the rate parameters of catalytic decomposition of trimethylamine, triethylamine, ethanethiol, dimethyl sulfide and diethyl sulfide with a commercial spherical Pt/Al203 as a function of temperature (480-680 K), initial molar concentration (500-2000ppm), and oxygen concentration (0.21-1.0 mole fraction).
A continuous stirred tank reactor model with draftiness was chosen as a mathematical model for the tublar reactor, because the inner diameter of the tublar reactor was about 5times as large as the particle diameter. On the basis of this mathematical model, experimental results were analyzed by the nonlinear least squares method. The following overall rate equations were obtained: for trimethylamine (Fig.8 and Table 2), for ethanethiol (Fig.10 and Table 4), for dimethyl sulfide (Fig.11 and Table 5), and for diethyl sulfide (Fig.12 and Table 6).

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The adsoptive capacity of the zirconium(IV) oxide hydrate-active carbon complex (ZrO₂. H₂O-A. C) toward arsenate ions has been investigated. A mixture of an aqueous solution (50 ml) of ZrOCl₂·8 H₂O (2.2-11 g) with granular active carbon (50 ml; 22.5 g) was heated at 160°C with evolutions of water and hydrogen chloride. The product obtained was washed with water to hydrolyze the deposited substance on the active carbon to ZrO₂. x H₂O, and then dried at 110°C. The granular active carbon contained the basic oxides of Fe, Ca and Na, which could adsorb arsenic(V) ion. The deposition of Fe₂O₃. H₂O on the active carbon increased the adsorptive capacity of arsenic(V) ions but the regeneration of the product was impossible. The ZrO₂·H₂O-A. C complex was regenerated by aqueous solutions of NaOH and HCl. Arsenate ions were adsorbed on the ZrO₂-H₂O-A. C complex in acidic and neutral solutions after oxidation of arsenic(III) to arsenic(V) by a catalytic activity of the surface of the complex. Such ions as Na+, K⁺, Cl^-, NO₂- and SO₄2- showed no effect on the adsorption of arsenic(V) ions, but Me and Ca2+ ions shigtly increased the amount of the adsorption owing to the formation of insoluble arsenates. PO43- ion decreased the adsorptive capacity. In a column test, the breakthrough point of the arsenate ions was 330 l/l when the inlet arsenic(III) concentration was 50 mg-As₂O₃/l. It was found that the adsorptive capacity of arsenic ions in the second run became about 25% less than that in the first run, but further reduction in adsorptive capacity was not observed in the successive runs up to 10.

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