A new composite of technologies was developed and has been introduced in amateur-use color photographic papers. This consists of a key technology of a novel magenta coupler whose dye has excellent absorption characteristics and other two assisting technologies, i. e. a specific light stabilizer and anti-dirt (anti-stain) agents. The magenta coupler has a novel 1 H-pyrazolo[1, 5-b][1, 2, 4]triazole skeleton, which is quite different from an usual magenta coupler 5-pyrazolone, and which was a five ring-five ring fused heterocycle first synthesized by nitrogen-nitrogen bond formation reaction. Spiroindan compound was discovered mostly useful for a light stabilizer of p yrazolotriazole dye through the research of light fading mechanism and also by screening of various light stabilizers. This compound was found to act a quencher of singlet excited state participated by bimolecular pyrazolotriazole dyes (probably excimer) and has lead to 1.5-2.0 times faster magenta image on new color papers than that on the previous one. Anti-stain agents are an active carbonic ester (electrophile) a nd a sulfinic acid compound (nucleophile), which are designed to react effectively with p-phenylendiamine (color developer)and quinone dimine (oxidized color developer), respectively. Magenta stain, which is occasionally formed by oxidative coupling reaction of the pyrazolotriazole coupler and a very small amount of color developer remained in a paper after color development process, is completely suppressed by these two scavengers.

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In order to clarify the mechanism of tautomerization of 1-hydroxy-2(1H)-pyridinethione (HPT) giving 1-pyridinethiol 1-oxide, we investigated the effects of triplet quenchers and deuterium substitution on the phosphorescence behavior of a tautomeric HPT molecule at 77 K. The finding that both 2, 4-hexadien-l-ol and naphthalene quench the phosphorescence of enethiol isomer while the thione isomer phosphorescence is not affected by these quenchers (Figs.1 and 2) demonstrates that the tautomeric equilibrium between the thione and enethiol isomers cannot be established during the triplet-state lifetime of the thione isomer. This finding coupled with a consideration of the relative triplet-state energy of both tautomers makes the tautomerization in the excited triplet state (Scheme 2), proposed in our previous study (Ref.2), less likely. Deuterium substitution of the N-hydroxyl hydrogen in HPT suppresses the tautomerization to the enethiol isomer (Figs.4 and 5), whereas this substitution affects the UV spectrum of HPT to a negligible extent. Although this observation is consistent with the mechanism in which the ground-state enethiol isomer is generated photochemically from the thione isomer in excited states (Scheme 3), it is difficult for this mechanism to explain the effect of photoirradiation on the phosphorescence intensity ratio of two tautomers. From both an analysis of temperature and deuterium isotope effects on the UV spectrum of HPT and a comparison of the UV and fluorescence spectra of HPT with those of 2-ethylthiopyridine 1-oxide, it was found that the phosphorescence quantum yield of enethiol isomer should be much larger than that of thione isomer, and thus that the ground-state tautomeric equilibrium (Scheme 4), which lies practically completely in favor of the thione isomer, is reflected much more remarkably in the phosphorescence behavior than in the fluorescence behavior.

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An amperometric solid-state sensor using a proton conductor (antimonic acid) thick film was developed for detecting small amounts of hydrogen in air at room temperature. The thick film (ca.10 μm) was formed on a porous alumina substrate by a spin-coating method (Fig.1). The sensor element had a laminated-type structure in which the thick film was sandwiched by an inner and outer electrodes (sputtered platinum) (Fig.2). The short-circuit current of the sensor was in direct proportion to the hydrogen concentration in the range from 200 ppm to 6000 ppm (Fig.4). The 90% response time to 1000 ppm H2 was as short as 10 s at 30°C (Fig.3). The direction of the current was reversed when the outer electrode was changed from sputterd platinum to platinum black (Figs.3, 7) and this was ascribable to the difference in activity of the electrodes for the electrochemical reduction of oxygen (Fig.5). The large humidity dependence of the current response could be mitigated when the circuitry was modified to include resistance (in series) with the sensor element (Fig.8). The current response in the modified circuitry was also proportional to the hydrogen concentration (Fig.9).

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The catalytic hydrogenolysis of endo/exo isomers of amino- or dimethylamino-substituted bicyclo[3.1. Olhexane and bicyclo[4.1.O]heptane with Pd-C and Raney Ni catalyst was studied in order to investigate the regioselective behavior of the amino and N, N-dimethylamino groups on the cyclopropane ring hydrogenolysis. When the hydrogenolysis carried out in hexane or pentane, the endo and exo isomers of the bicyclo[3.1.O]hexane and bicyclo[4.1.0]heptane were hydrogenolyzed at the adjacent bond of the substituent, whereas the opposite bond of the substituent was hydrogenolyzed in acetic acid solution. The endo isomers of the bicyclo [3.1. O]hexanamines were hydrogenolyzed readily at the opposite bond accompanied by the synchronous elimination of the subsituent and the exo isomers of the bicyclo[4.1.0]heptanamines were hydrogenolyzed slowly at the opposite bond without elemination of the subsituent. These results show clearly the difference of the role between the amino group and the ammonio group. The amino group adsorbs tightly to the catalyst surface and assists the cleavage of the adjacent bond. In the case of the ammonium compounds, the driving force of the hydrogenolysis is releasing the strain which causes the preferential cleavage of the opposite bond. Furthermore, the synchronous elimination of the endo ammonio group contrihutrs to accelerate the reaction.

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7, 7-Difluro-, 7-chloro-7-fuluoro- and 7-bromo-7-fluorobicyclo[4.1.O]heptanes were hydrogenated over Pd-C in methanol solution at room temperature under the atmospheric pressure or at 80°C under 50 kg/cm' in order to investigate the effect of halogens in the regioselective cleavage of the cyclopropane ring and the effect of amines as additives. The hydrogenolysis of the cyclopropane rings occurred at the C₁-C₅ bond selectively to give ring-enlarged products. The endo-fluoro isomers gave cycloheptane solely while the exo-fluoro isomers gave cycloheptane and fluorocycloheptane. The addition of amines retarded the cleavage of the ring but accelerated the hydrogenolysis of the C-Br bond. The hydrogenation of 7fluoro-, 7-chloro- and 7-bromobicyclo[4.1.O]heptane was investigated under the same conditions. The endo-isomers of 7-fluoro and 7-chloro derivatives were hydrogenolyzed at the C₁-C₆ bond to give cycloheptane but the exo-isomers resisted to the hydrogenolysis. On the other hand, the endo-7-bromo derivative was cleaved at the C₁-C₆ bond accompanied by the cleavage of the C-Br bond and the exo-7-bromo derivative was cleaved at the C-Br bond preferentially accompanied by the cleavage of the C₁-C₇ bond.

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Garnet-type Y₃Fe₅O₁₂ powders were synthesized using an amorphous citrate process. The amorphous citrate precursor gel prepared through a liquid phase was at first thermally analyzed in air up to 1000°C a ta heating rate of 10°C/min by means of TG-DTA in order to study its thermal decomposition process. The gel was calcined at 800, 900 and 1000°C in air since no weight change of the sample was detected above 800°C in the TG curve. The powders thus calcined were molded into pellets and sintered in air under various conditions. The sinterabilities of the powders were studied in comparison with those prepared by a solid state reaction of Y₂O₃, and Fe₂O₃ powders. In the amorphous citrate process, the maximum density of 4.83 g/cm³ (93.3% T. D. ) was obtained for the pellet sintered at 1450°C for 2 h using the powders calcined at 900°C for 2 h. Microstructure of its fracture surface observed with a SEM showed its grain size was small and uniform, although the maximum sintered density was lower than that from the solid state reaction. From the XRD line profile analysis and its results on the XRD peak positions for CuK a, radiation, crystallite sizes and lattice constants characterizing the resultant Y₃Fe₅O₁₂ bodies were estimated to be about 30 to 33 nm and 1.236 to 1.236 nm in the calcining range of 800 to 1000°C, respectively.

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In order to investigate the transport of soil particles and pollutants t o the ocean and their concentration distribution in the marine atmosphere, atmospheric concentrations of Al, Si, Fe, S and Cl were measured in the Pacific Ocean, the Indian Ocean and the Antarctic Ocean. The marine aerosol samples, collected on board the Antarctic observation ship "Shira se", were analysed by X-ray fluorescence analysis. The samples were taken every day by the low volume air sampler at the flow rate of 20-30 //min, during the cruises of "Shirase" from Tokyo to Fremantle in November 1988, from Fremantle to Syowa station in December 1988 and from Syowa station to Sydney in March 1989. As a result, the average concentrations of soil derived elem e nts were 11.9 ng/m³ for Al, 50.6 ng/m³ for Si, 12.6 ng/m³ for Fe, over the western Pacific Ocean between Tokyo and Fremantle. These values were so low as 1/100 of atmospheric concentration in the land. Especially, over the Indian Ocean and the Antarctic Ocean between Fremantle and Syowa station, concentrations were very low, 6.5 ng/m³ for Al, 13.4 ng/m3 for Si, 3.5 ng/m3 for Fe with average. It is considered that these values are the background concentrations of soil derived elements in the marine atmosphere. The main source of S and Cl in th e marine atmosphere is sea salt. Therefore, a strong correlation between concentrations of S and Cl was observed over the Indian Ocean and the Antarctic Ocean. However, over the western Pacific Ocean between Tokyo and Fremantle, a correlation between concentrations of S and Cl was not observed. The concentration of S was highly correlated with that of soil derived elements. The western Pacific Ocean was not far from the land such as Asia Continent and Southeast Asia. It is considered that S orignated from oil burning in East Asia and Southeast Asia with soil particles. The marine atmosphere over the western Pacific Ocean is strongly influenced by anthropogenic sources in the land.

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Active carbon has been widely used as a low-priced adsorbent. However, there are only few applications on isolation of alkyl glycosides. In this paper, adsorption of alkyl glycosides to active carbon and its application in the isolation of alkyl glycosides were investigated. Alkyl β-glucosides and alkyl β-xylosides were used as representatives of alkyl glycosides. The results suggest that the degree of adsorption of both alkyl β-glucoside and alkyl β-xyloside to active carbon increased with the alkyl chain of the glycoside. (Fig.1 and Table 1). Active carbon column chromatography was used for the purification of alkyl β-xyloside (for example isopropyl β-xyloside) which was synthesized by utilizing the transxylosyl activity of Aspergillus niger /3-xylosidase. Stepwise elution with distilled water and 5%(v/v) ethanol solution was employed and 2.3 g of isopropyl β-xyloside was obtained from 10 g of xylobiose (Figs.2 and 3). Furthermore, heptyl p-xyloside, a nonionic surfactant, adsorbed to active carbon irrespective of its concentration and was recovered almost quantitatively from the active carbon when eluted with 50% (v/v) 1-propanol solution (Fig.4). The adsorptive capacity of 1 g (dry weight) of active carbon was approximately O.5 g for heptyl β-xyloside.

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The stereoselectivity of group 8 metal catalysts has been examined in the hydrogenation of 2, 3-butanedione (1) and 3-hydroxy-2-butanone (2) at ambient temperature under atmospheric pressure of hydrogen. At the initial stage of the catalytic hydrogenation of 1, the primary product was found to be 2 over every catalyst.2, 3-Buatnediols (3) were produced over cobalt, nickel, ruthenium, osmium, iridium and platinum catalysts in further reduction, but 2 was not hydrogenated to 3 over palladium and rhodium catalysts. The catalytic hydrogenation of 1 over Raney nickel and cobalt, or ruthenium and iridium black catalysts yielded a small excess of meso-isomer of 3. A platinum black catalyst gave a high yield of meso-3 from 1 and 2. From these results, it seems that the catalytic hydrogenation does not proceed directly in the 1→3 fashion, and that the isomeric ratio of 3 (racemic to meso) reflects the stereochemistry of 2, the primarily-desorbed product, on the surface of respective catalysts.

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Deithyl 2, 3-pryridine dicarboxylates 3 were easily prepared in one pot synthesis by the reaction of a-chlorooxaloacetate 1, a, p-unsaturated aldehydes 2 and ammonia. Especially, diethyl 5-ethyl-2, 3-pyridine dicarboxylate 3a was obta i ned in a good yield (81%) by the reaction of 1, 2-ethyl-2-prop enal 2a and ammonia in chloroform using an autoclave. In the reaction in an autoclave, the yield of 3 a in chlorobenzene or toluene was similar to that of chloroform. But under atmospheric pressure, the yield of 3a was lower in toluene, benzene, and ethanol than in chlorobenzene.

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The Institute of Space and Astronautical Science Sagamihara-shi 229 Japan The stratospheric ozone significantly protects the life from the harmful ultra-violet solar radiation. In a broad way, stratospheric ozone is produced in a low-latitude region, transported to polar regions, stored, then becomes extinct there. The decrease in ozone concentration in the antarctic region is watched in recent years, but the ozone trend in the low-latitude region, which is the ozone yielding region, is no less important. Dutch's model in 1966 indicates that the total column ozone in the low-latitude northern hemisphere in April is less in the half-circle region around 180°of longitude than in the half-circle region around 0°, and there is the high-density region around 90°. The cause for this distribution has not been manifested yet; They suppose that it is due to topographical effects on the atmospheric circulation. In the present study, we analyze the stratospheric ozone distribution in the low-latitude northern hemisphere by using the data from LAS (Limb-Atmospheric Infrared Spectrometer), which was born on the satellite "OHZORA" (EXOS-C). We confirm that the longitudinal distribution of the total column ozone near surface is essentially in good agreement with Dutch's model and TOMS data. We could obtain the distribution maps at various altitudes. The altitude distribution indicates that the longitudinal variation is large at 40 km and 30 km, where the chemical process in ozone production is important. The longitudinal distributions at these altitudes are very similar to the total ozone distribution. This results indicate that the ozone distribution cannot be explained only by the topographical effect on the atmospheric circulation, and that longitudinal effects on the ozone chemistry in the upper stratosphere are significant. A hypothetical model is described for the present results.

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A conversion of nitrate to nitrite, reduction of nitrite to nitrogen monoxide, gas-liquid separation and a detection of nitrogen monoxide with second-derivative spectrophotmeter are used for continuous or accumulation determination of nitrite and nitrate in seawater. The sample is pumped at 4 ml/min through a converter containing cadmium-copper powder which converts nitrate to nitrite. The effluent is mixed with reducing agent (1 ml/min)(0.13 M sodium iodide-13 M phosphoric acid), which reduces nitrite to nitrogen monoxide at 40-50°C, and the mixture is fed through a gas-liquid separator (pore size 1 gm, microporous Teflon tube, 2 mm o. d., 1 mm i. d.50 cm length). Nitrogen monoxide evolved from a gas-liquid separato r is determined by either continuous system or accumulation system. In the continuous system the nitrogen monoxide evolved is purged by nitrogen (150 ml/min) into a heated optical cell (light pass length 25 cm, cell volume 80 ml, 150°C), where the second-derivative absorbance at 214.0 nm is recorded. Nitrite is determined directly while nitrate is determined indirectly and the sample throughput is 5/h. The method has detection limits of 1×10^-6 M nitrite and nitrate and has been applied to chlorine water. In the accumulation system nitrogen monoxide accumulated (20min feeding time) in the gas layer of separator is introduced by nitrogen into the evacuated optical cell of which operation conditions are same as that of continuous system. The method has detection limits of 2×10^-8 M of nitrite and nitrate and has been applied to seawater. The sample throughput is 2/h. The conversion efficiency of nitrate to nitrite with cadmium-copper column and the reactivation were evaluated by accumulation system.

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Copper in water was determined by a spectrophotometric method involving flow injection coupled with solvent extraction. An ion associate formed between dihalogenocuprate(I)ion and a dye cation was extracted into an organic solvent and the absorbance of the separated organic phase was measured. Three triphenylmethane dyes and three analogues of the azo dye 4- (4-diethylaminophenylazo) N-alkylpyridinium cation were examined as counter cations, and three kinds of dihalogenocuprate(I) ions and various kinds of extraction solvents were examnied. The best extraction system for FIA was the system CuBr₂ ^--PEP⁺ (the propyl derivative of the azo dye)-chlorobenzene. The carrier stream was 0.02 M L-ascorbic acid solution, the reagent stream contained 10^-4 M PEP⁺ and O.03 M KBr (pH 5), and the extraction solvent stream was chlorobenzene. The organic phase was separated with a polytetrafluoroethylene porous membrane. The sampling rate was 30 per hour. The calibration graph was linear at concentrations below 3×10-5 M using samples of 300 id. The detection limit corresponding to a signal to noise ratio of 3 was 2×10^-8 M, and the relative standard deviation for 11 measurements of 1×10^-6 M copper solution was 0.7%. Anionic surfactants were separated from the peak of copper by using a 3 m dilution coil.

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The three methods for the mass spectrometric determination of volatile chlorocarbons were developed. In the discharge-CIMS method, atmosphere sample was directly introduced into the ion source through a short capillary tube (0.25 mm i. d.×1 m). And (M-Cl)⁺ for 1, 1, 1-trichloroethane, M⁺ for trichloroethylene and M- for tetrachloroethylene, which formed by ionization reactions such as charge exchange or nondissociative electron resonance capture with air as the reagent gas, were monitored. In the GC/NCIMS methods wihout or with preconcentration using the collection tube packed with Tenax GC and active carbon, chloride ion Cl^- produced by dissociative electron resonance capture were detected by selected ion monitoring for detecting chloroform and carbon tetrachloride as well as the above 3 cornpounds. The detection limits were 0.5-1 ppb by discharge-CIMS and 0.01-0.1 ppb by GC/NCIMS with a precision of RSD 3-6%. Chlorocarbons in the atomospheric and the indoor air in many places were determined by the proposed methods.

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A simple diffusive ozone sampler, which allowed to determine atmospheric ozone with high sensitivity, was developed. It utilized oxidative dimerization of p-acetamidophenol by ozone, which gave a strongly fluorescent dimer. The fluorescence intensity was measured at 425 nm with excitation at 337 nm. The determination limit was 2 ppb for one-hour exposure. Fluorescence intensities measured by the present method showed a good linearity with ozone concentrations determined by an ultraviolet-absorption ozone analyzer. The effects of the temperature, humidity, wind velocity and wind direction on the obserbed values were within a tolerance limit.

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The river water of the Yoshinogawa was investigated by ion chromatography and discussed on characteristics of water. Water temperature, pH, electric conductivity, anion concentrations (chloride, phosphate, nitrite, nitrate, sulfate ions), and cation concentrations (sodium, ammonium, potassium, calcium and magnesium ions) were measured. The ion concentrations increased almost linearly toward the lower reaches of the river. And the electric conductivities were nearly proportional to the ion concentrations in this river. The equations between electric conductivity and dissolved ion concentrations (chloride, nitrate, sulfate, sodium, potassium, calcium and magnesium ions) in the river water were proposed. High correlations were obtained. In all ions, coefficient of correlations were O.955 or above. Accordingly, ion concentrations of the river water were estimated from electric conductivity by proposed equations and compared with the analytical values obtained by ion chromatography. The equations were also applied to the data of the Yoshinogawa water after 2 years. These values were in fair agreement with the analytical ones except nitrate ion.

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The EPMA of studded tire-generated dust (dust fall) in winter season in the Matsumoto area (about 600 m above sea level) in Nagano Prefecture was carried out by a SEM equipped with an EDS instrument. The sample was collected in a dust jar during winter season as dust fall. The characteristic particles in the EPMA data are as follows : 6-2, spherical porous shape; main element, sulfur; followed Si, Al; about 40 pm, 6-9, long and slender shape; main element, Si and Al; 91-4 long and slender shape about 50 pm; main element -5, Fe sharp peak; 91-1, Mg relatively large peak, respectively (Figs.1-4).

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Department of Applied Chemistry, Faculty of Science and Technology, Keio University; Hiyoshi, Kohoku-ku, Yo kohama-shi 223 Japan The daily and weekly variations of the concentration of tire tread in the atmosphere were measured at the high density urban area in Shinjuku, Tokyo in summer and spring. The air samples were continuously collected through the monitoring periods with a 4-8 h sampling cycle to discuss the variations of the concentrations of tire tread in relation to a fundamental cycle of human activities. The concentration of tire tread in the urban air was clearly high in the day time compared to that in the night and higher weekdays than sunday. These tendencies are in accordance with a cycle of human activities or a cycle of daily life in the urban area. The concentration of tire tread in Hiyoshi, Yokohama located about 20 km from the center of Tokyo depends on the direction of the wind. Particularly, it was high when the wind came from the north-west and the north-east. The vertical distribution of tire tread in the atmosphere indicated that the particle sizes of tire tread are larger than those of suspended particulate matter other than rubber particles.

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The concentrations of tire tread and inorganic salts in suspended particulate matter were measured in the high density urban area in summer and spring (Aug.1988 and March 1989). One of the sampling sites was located in the high density urban area of Shinjuku, Tokyo and another was in Hiyoshi, Yokohama about 20 km south-west of Tokyo. The concentration and vertical distribution of cations such as ammonium and sodium ions as well as anions such as chloride, nitrate and sulfate ions were monitored and compared to those of tire tread in the urban area. A good correlation was found between the concentration levels of ammonium ions and those of sulfate ions. The variation of the concentrations of tire tread in the urban atmosphere is highly correlated to that of suspended particulate matter. The daily and weekly behavior of tire-tread particles in the high density urban area is explained by a cycle of human activities such as motor vehicles. A useful component for the evaluation of air quality was found to be tire tread by examining a correlation of the concentrations of tire tread to those of inorganic salts and to human activities in the urban area.

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The seasonal variation of mutagenic activity of air at residential site in Sapporo City was studied over a two year period. Particulate matter was collected on tissue quartz filters for 5 days per month with the standard high-volume air sampler. The mutagenic activity of extracts was tested by the Ames Salmonella assay with and without liver S 9 fraction. The monthly average of the mutagenicity varied between 5.2 and 48.2 revertants/m³ of air for TA 98 and between 2.4 and 44.5 revertants/m3 of air for TA 100 with and without liver S 9 fraction. The increasing order of mutagenic activity per cubic meter of air was clear (summer <spring <autumn <winter). The mutagenicity was 4-6 times as high for the winter period as for the summer period. The monthly variation of mutage nicity showed a pattern similar to those of PAH, 1-NP concentration and kerosene consumption for space heating. The mutagenicity was strongly correlated with PAH and 1-NP concentration. The mutagenicity was negatively correlated with the temperature below 10°C but not correlated between 15°C and 20°C. BaP accounted for 0.3-2.0% and 0.7-4.5 % of the indirect acting mutag enicity of the whole extracts with TA 98 and TA 100, respectively.

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In order to estimate the origin of polycyclic aromatic hydrocarbons (PAHs) in surface and core sediments from The Western Sea of Suo, the horizontal and the vertical distributions of PAHs and the composition ratio of PAHs (BkF/BaP) in sediments were investigated. Moreover, the topographic factor of this sea area and the relationships between heavy metals concentrations and PAHs concentrations have been investigated. Two compossition ratios of PAHs (BaP/BghiP, BkF/BaP) in atmospheric suspended particulate matter that were admitted a difference to these composition ratios with each emission sources, were util ized to estimate of the origin of PAHs in sediments. On the vertical distribution, an evide nt change appeared in the composition ratio of PAHs (BkF/BaP) in 4045 cm layer, corresponds to about 1920 by ²¹⁰Pb-chronology, at Site 23(Fig.2). On the other hand, surface sediments except for Sites 10, 15, 23 were classified into 2 groups (Cluster A and B) by the Cluster analysis. Significant difference in the composition ratio of PAHs (BkF/BaP) at each Cluster were found (Cluster A: 0.425, Cluster B: O.355). Furthermore, the difference was admitted to the slope of the regression line between Pb concentration and BaP concentration in each Cluster (Cluster A: 0.114, Cluster B: 0.054) (Table 3). At Cluster A, the relationship between Fe concentration and BaP concentration was linear (r=0.829), and PAHs concentrations in sediments correlated negatively with the depth of water (Fig.4). However, the correlation was not admitted between the distance from Site 20 and PAHs concentrations in sediments. On the other hand, the negative correlation was admitted between the distance from Site 20 and PAHs concentrations in sediments at Cluster B (except site 8) (Table 5). As these results, it was estimated that the origin of PAHs at sea area of Cluster A was mobile source and at sea area of Cluster B were both mobile source and industrial source, respectively.

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In order to clarify the behavior of dissolved organic substances in a shallow lake water, the western part of Lake Inba-numa was chosen and the stational, seasonal changes of the concentrations and component of the dissolved organic substances were examined. The lake is known as one of the most polluted lakes in Japan. Water sampling was made once in a week dur ing the period from June 1985 to June 1988. Each water sample was filtered through a 0.45 gm membrane filter and used for the determination of concentrations. From the se results, the mean values of the dissolved TOC of spring, summer, autumn and winter seasons in the western part of Lake Inba-numa were 8.8 mg/l, 9.8 mg/l, 9.4 me and 8.3 mg/l, respectively. The TOC value tends to increase from June to September and decrease from November to March excepting aquatic plant area but in the aquatic plant area this tends to increase from October to November. The dissolved TOC of summer season was composed of proteins, 22-27 %; carbohydrates, 24-32 %; volatile organic acids, 1022 % ; anionic surfactants, 2-3 % ; humic acids, 1-3 %; lignin, 1-4; tannin, 2-4 %; urea, 4-9 %; and lipids, 1-4 %. The sum of the components of proteins, carbohydrates, volatile organic acids and anionic surfactants was 68.8 % of dissolved TOC and that in the influent of domestic wastewater about 67 %. As one of the causes of the pollution of the western part of Lake Inba-numa, the influx of organic substances from the catchment area similar to those present in the domestic wastewater, may contribute greatly. The western part of Lake Inba-numa may be strongly affected by the matter production of Trapa vegetation.

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From the analysis of the desorption of inorganic phosphorus (IP) from the surface of river sediment heated at 550°C or untreated by an addition of NaHSO₃ aqueous solution, the presence of adsorption sites with different strength was postulated. IP released into 10 ppm, 10-100 ppm and above 100 ppm NaHSO3 solutions were tentatively defined as weaklyadsorbed, intermediately-adsorbed and strongly-adsorbed IP, respectively. The IP released into NaHSO₃ aqueous solution might be those adsorbed to Fe rather than Al which were present on the surface of sediment. From the model experiment for release, it was suggested that IP released from sediment was weakly-adsorbed IP. This method which is used to estimate weakly-adsor bed IP was applied to river waters. Seasonal variations of this weakly-adsorbed IP on the surface of sediment particles in different size and the relation between this IP and dissolved inorganic phosphorus in overlying water were studied.

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Behavior of organic matter in the airborne aerosols during the long -range transport of photochemical air pollution was investigated in summer (29-31 July 1986). Measurements were made for every 3 hours along the transport route from the Tokyo Bay area to the i nland mountainous region. C₂₁-C₃₂ n-Alkanes, phthalates (dibutyl and bis(2-ethylhexyl)), C₂-C₁₀ dicarboxylic acids, pinonaldehyde, C₁₀-C₂₆ fatty acids, nonpolar unresolved complex mixture (NPUCM) and polar unresolved complex mixture (PUCM) were detected and their fraction of anthropogenic and natural components and those of primary and secondary compo nents were discussed. Concentration of organic matter in total increased when the poliuted air ma ss arrived at the observation sites. NPUCM and PUCM were much abundant. From the ratio of odd and even carbon number components, more than a half of n-alkanes was estimated to be anthropogenic. Biogenic compounds (pinonaldehyde, long-chain C₁₂-C₂₆ fatty acids and nalkanes)were minor contribution in the airborne aerosols, a large part of them, in particular the pinonaldehyde which was produced in the photochemical reactions, however existing in the gaseous phase in the daytime. Almost all of dicarboxylic acids and about a half of NPUCM and PUCM were also produced during the transport. Thus, the secondary components attained 42-53 % of organic compounds analyzed in the polluted air mass over the inland area. Here, the organic compounds analyzed, including NPUCM and PUCM attained 30-50 % of the total organic carbon.

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Coulometric measurements of electroreduction of CO₂ were conducted with a Cu electrode in the presence of Cd²⁺ in the electrolytes (KHCO₃). Cd²⁺ is deposited durng the reduction (in situ electrodeposition). Fig.2 shows the current efficiencies of the products plotted against the apparent coverage of Cd (S). With an increase in the deposited Cd, hydrocarbon formation decreased, whereas CO and HC00- increased. The CO formation reached a maximum at 8=1. The amounts of Cd on the Cu electrode, composed of adatom and bulk (multilayer) Cd, were measured by the anodic stripping method, and agreed well with those calculated under the assumption of random deposition model under the limiting current conditions. These results indicate that CO is formed on the adatom Cd on the Cu electrode.

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Chelate resin, together with cation-exchange resin, is used as deodorant. Much is not known about the cobalt ion, which is the center metal atom in the chelating system, particularly about its oxidation state and coordination state in the process of deodorant reactions. Therefore, an ESR study of this resin has been tried. The ESR spectra observed, when the resin was set in a vacuum line and either NH₃ or H₂S was introduced into it, showed that there are two differently reactive (with respect to redox reactions) cobalt ions in the system. They are suggested to be two differently coordinated cobalt ions, namely six- and four-coordinated ions. The four-coordinated ion has higher reactivity. It has also been suggested from the results of ESR spectra that the four-coordinated cobalt ion can, catalytically, oxidize H₂S with air.

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Reduction of NO into N₂ was examined in a fixed bed flow reactor at 200∼350°C and W/F=1/50∼1/200 g°min/ml over PAN-ACF, Pitch-ACF and active carbon, and their Cu a nd Fe salts (5 wt%) supporting forms. PAN-ACF reduced NO at a conversion of 30% in the very initial stage at 350°C, but it lost activity rapidly to 10% within 3 h. Supporting the salts enhanced the reduction to give the stationary conversion of 55∼60%. Addition of O₂ to the reactant gases markedly increased the NO conversion to 82∼100% at 250°C, producing a large amount of CO₂ at the same time. Copper (II) acetate supported on PAN-ACF exhibited the highest reactivity at smaller carbon consumption. CO and propylene in the reactant gas suppressed the consumption of carbon with slight decrease of NO conversion. Copper (I) salts appeared to be reduced into copper(II) oxide on PAN-ACF at the reaction temperature to give the catalytic actibity. Best dispersion of the oxide from copper acetate on PAN-ACF may be the main reason for its best activity and selectivity

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The composition of wastewater is becoming more complex with the development of new technologies and new materials. One of the difficulties to be overcome in the wastewater treatment is contamination with organic components, which make the neutralizing coagulation of heavy metals diffcult. This paper describes the effects of soluble aromatic compounds bearing one or two OH, CO₂H, NH₂ groups, in coagulation. The mono-substituted benzene derivatives, phenol, benzoic acid, and aniline, did not interfere with the coagulation of Cu. However, in the cases of o-disubstituted benzene derivatives, especially Catechol, Salicylic acid, and Aminophenol, coagulation was impossible. The effects of these compounds in coagulation are explained in terms of formation of complexes of Cu and their solubilities.

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The purpose of this study is to reveal the chemical characteristics of gelation reaction of the soil stabilizer. Analysis of composition of the soil stabilizer (Table 1) and the gel (Table 2 and Fig.3) showed that 80% of formaldehyde in the soil stabilizer exists as the form of N, N'bis(hydroxymethyl)urea (BHU) and the gelation process is essentially an acid-catalyz e d condensation reaction of BHU with urea. The“gel”was found to be the condensation products of 2 molecules of BHU with 1-3 molecules of urea, i. e., N, N'-bis(hydroxymethyl)-5oxo-2, 4, 6, 8-tetraazanonanediamide 7, N-hydroxymethyl-5, 9-dioxo-2, 4, 6, 8, 10, 12-hexaazatridecanediamide 5 and 5, 9, 13-trioxo-2, 4, 6, 8, 10, 12, 14, 16-octaazaheptadecanediamide 6, depending on the amount of urea added. Effects of gelation conditions such as gelation time (Table 4), amount of urea added (Fig.6), concentration of sulfuric acid (Fig.7), amount of water added (Fig.8) and gelation temperature (Fig.9) on the gelation reaction were also examined. These results are consistent with the proposed reaction scheme which includes the formation of Nhydroxymethyl2, 4-diazapentanediamide 8 as a common intermediate (Reaction Scheme of Gelation).

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The hydrodesulfurization of dibenzothiophene and 2, 8-die thyldibenzothiphene over the sulfied CoMo/Al₂O₃ catalyst was studied using a batch method. The experiment was carried out at 250∼350°C and 5.0 MPa of H₂ initial pressure for 4 h. The hydrogenation of biphenyl did not take place until dibenzothiophene was converted completely. The hydrodesulfurization of 2, 8-diethyldibenzothiophene proceeded more readily than that of dibenzothiophene. The percent desulfurization and the amount of H₂ consumption of 2, 8-diethyldibenzothiophene was 1.9 and O.27 times those of dibenzothiophene, respectively (Table 1). The results showed that 2, 8-diethyldibenzothiophene was desulfurized more easily than dibenzothi ophene with relatively samll amount of H₂ consumption during hydrodesuljurization.

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Matsugasaki, Sakyo-ku, Kyoto-shi 606 Japan Halogen atoms (Cl and F) of 1, 1, 2-trichloro-1, 2, 2-trifluoroethane (CFC-113)) were efficiently (nearly 100%) removed as sodium chloride and fluoride by treatment with sodium dihydronaphthylide in THF at room temperature under UV light irradiation. The rate of defluorination under the irradiation was found much faster than that without irradiation, thus the defluorination was completed at a room temperature within 100 min. Analysis of the reaction intermediates was also carried out by a capillary GC-mass spectroscopy to show that the major intermediates were produced by the coupling reaction between dihydronaphthylide and two-carbon unit of CFC-113.

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The pH data was collected at the 29 stations in Phase- I study of Acid Precipitation Survey over Japan by Japan Environment Agency in terms of frequency distribution patterns. This study was undertaken from April 1984 to March 1988, which was the first survey of acid precipitation over Japan with identical sampling procedures and subsequent chemical analyses.
While the annual mean pH at each station ranged from 4.4 to 5.5, the monthly mean varied more widely, from 4.0 to 7.1. Its frequency distribution pattern was obtained for each station, and further grouped into four classes: class I; a mode at the rank of pH 4.54.9, class II ; bimodes above and below this pH region, class III; a mode at a higher pH region, class IV ; a mode at a lower pH region. The bimodal pattern was suggestive of precipitation with and without incorporation of significant amounts of basic aerosol of anthropogenic origin during descent of rain droplet. The patterns of the stations were also classified on a basis of summer-winter difference into another four classes. Winter pH values were appreciably lower than summer pHs in western parts of Japan and on Japan Sea coast, we attribute the winter pH to probable contribution of acidic pollutants transported by strong winter monsoon from Eurasian Continent. At most stations in northern and eastern Japan, the pH was higher in winter months reflecting more incorporation of basic materials, e. g., NH₄⁺ and Ca²⁺.

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Precipitation of atmosphric pollutants was collected by bulk type filtered acid precipitation sampler (Filtered sampler, Japan Environmental Agency type) in Japan from April, 1984 to Match, 1988.
Assum ing that precipitation acidity originates primarily from sulfuric and nitric acids, the equivalent ratio of NO₃^- to SO₄^2- (N/S ratio) was discussed in oder to assess the relative importance of their contributions to precipitation acidity. The ratio was higher in urban areas on Pacific Ocean coast ranging from Hiroshima to Sendai. Particularly, Musashino, Tokyo receives the heaviest deposition of NO₃^- (3.3 g°m^-2°y^-1) in the 29 stations, reflecting large amount of NOx emitted in Tokyo Metoropolitan, which resulted in the highest N/S ratio as well as lowest pH. In contrast, this ratio was lower on Japan Sea coast, from Kyoto to Hokkaido. This region was characterized by considerably large SO₄^2- deposition during winter months. In Toyama, for instance, SO₄^2- deposition amounted to as large as 8.4 g°m^-2°y^-1 as an annual mean. The N/S ratio-pH relations demonstrated that the potential contribution of SO₄^2- to acidity exceeded that of NO₃^2-, especially in Toyama and Ishikawa areas.

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Rainwater was collected by wet/dry sampler (wet: event basis sampling, 553 samples) in Kobe area from June 1984 to May 1990, and the concentrations of dissolved ions, pH and electric conductivity in the water were determined. The annual mean pH values ranged from 4.27 to 4.50 with a mean of 4.39 and mean H⁺ depositin was 0.043 g⋅m^-2⋅y-^-1. The pH values were high in light rain (<10 mm rainfall) and the seasonal variation was not clarified. More than two-third of pH values were pH 4∼5, and the values for light rain were in wide range (pH 3∼7), and the values for heavy rain (>30∼40 mn rainfall)corresponded to the annual mean values. Major ion concentrations averaged over all the samples were as follows; SO₄^2-: 2.55, NO3^-: 1.17, Cl^-: 1.68, NH₄⁺: 0.32, Ca²⁺: 0.47, Mg²⁺: 0.14, K⁺: 0.08, and Na⁺: 0.77μg⋅ml^-1. The equivalent concentration ratios of NO₃^-/nss-SO₄^2-, NH₄⁺/nss-Ca²⁺ and (NO₃^- + nss-SO₄^2-)/(NH₄⁺+nss-Ca²⁺) were 0.39, 0.90 and 0.59, respectively.

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The regional distribution of deposition fluxes of soluble chemical species in bulk precipitation was determined (Figs.2 to 11). The monthly precipitation samples were collected at 41 urban and rural sites of the western Tokyo of Japan (Fig.1), from June to July of 1988, and analyzed for Na⁺, K⁺, NH₄⁺, Mg²⁺, Ca²⁺, Cl⁺, Br⁺, NO₃^-and SO₄^2-by ion chromatography and atomic absorption spectrometry. Hydrogen ion flux was evaluated by the mass balance calculation which assumes that any charge discrepancy in favor of anions is due to hydrogen ion flux. Based on the assumption of the sodium ion being derived from sea salt, the enrichment factor calculations indicated that sea salt is a minor source for the other ion species (Table 2): the maximum contribution of sea salt is 34% for Cl^-. In order to find out the characteristics of deposition flux pattern in geography, sampling sites were located along a 50 km line from coastal industrial zone to mountainous area. Deposition fluxes of Na+, NH₄⁺, Mg²⁺, Ca²⁺, Cl^- and SO₄^- decreased with increasing distance from the coast. Deposition fluxes of NO₃^- and H⁺+NH₄⁺ were different from those of the other ions. A high acid deposition was found in Machida, 20 km far from the coast. These regional distribution patterns indicated that CaSO₄, MgSO₄ and (NH₄)₂SO, were released from the coastal zone, probably as primary particulate matter. The difference of deposition flux patterns between acid substance and sulfate salt was also briefly discussed.

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Rainwater was collected in Saga city from January to December, 1989 to determine pH and major ions: Na⁺, K, Ca²⁺ mg²⁺, NO₃^-, NO₂^-, NH₄⁺ and Zn²⁺. The pH values range from 4.00 to 5.90 with a volume weighted mean value of 5.01. The free acidity was derived both from sulfuric and nitric acids. The [SO₄^2-]nss and [Ca²⁺]nss were evaluated from the Nat concentration under the assumption that all of the Nat originated from sea salt. The amount of [SO₄^2-]nss and [NO₃^-] (eq dm-3) was lower within Saga city than other cities. As [SO₄^2-]s in rainwater of other cities is lower than that of Saga city, the difference between [SO₄^2-]nss+ [NO₃^-] and [Ca²⁺]nss+[NH₄] is somewhat lower that of other cities. Therefore pH of rainwater within Saga city is somewhate higher than that of other cities.

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