The surface state of negatively charged mixed micelle prepared by addition of anionic surfactant, sodium dodecyl sulfate (SDS), to nonionic heptaethylene glycol dodecyl ether (HED)has been investigated and the surface potential (Δψ) of the micelle has been estimated by measuring the fluorescence intensity of ammonium 8-anilino-1-naphthalenesulfonate (ANS) as a fluorescent probe. A correction was necessary for the fluorescence intensity of ANS because of its absorption (Fig.1).
Since the binding coe fficient of ANS, K, is dependent on the surface potential of the micelle, the value of Δψ was determined according to the equation Δψ=-59.16 log (Ko/K)at 25°C, where Ko, is K of HED micelle. As the result, it has been found that (-Δψ)increases with mole fraction of SDS (x_SDS) when the ionic strength (J) is kept constant, and decreases with J when x_SDS is kept constant, as illustrated in Fig.8 and 10, indicating the effect of the negative charge of SDS and of ion atmosphere of Na⁺, respectively. Surface charge density ( σ ) was, therefore, determined from Δψ according to the Gouy-Chapman theory and the value of σ was found to be nearly independent of J and proportional to x_SDS, as shown in Fig.9. These results lead to the conclusions that ANS enters in the Stern layer at the micelle surface and that the state of diffuse layer surrounding the Stern layer is represented well with the Gouy-Chapman theory.

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The reducibilities of heteropoly compounds with carbon monoxide (CO) was drastically affected by their countercations. Among the following salts of H₃PMo₁₂O₄₀, i e., A g⁺, Na⁺, K⁺, Cs⁺, Ni2⁺, cu²⁺, zn²⁺, , mg²⁺, Ca²⁺ and Fe³⁺, nickel salt was most readily reduced and copper salt was next (Fig.1). Other salts were less reducible than the two and show ed almost the same or even lesser reducibility than H₃PMo₁₂O₄₀ tself. Silver salts, whic h was highly reducible by hydrogen, was hardly reduced by CO. It was found in Fig.4 that t he reduction of copper salt occurred through two stage processes: in the first stage the counterc a tions, Cu(II), were reduced to a lower valency state and in the second stage M o(VI) in polyanions were reduced. Temperature programmed desorption of CO for a variety of oxidize d and reduced 12-molybdophosphates revealed that the reduced salts of nickel and copp er had an ability for CO adsorption while oxidized salts and reduced acid as well had no abili t y.. These findings indicate that the role of countercations in the reduction is to adsorb CO which then react with polyanions. This clearly explains the presence of induction period which was found in the low temperature reduction of copper salt.

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The oxidative dehydrogenation of 1-butene to 1, 3-butadiene was investigated with Fe-Sb-O catalysts. The catalytic activity tests were carried out by a conventional flow method under the atmospheric pressure. By the use of a pulse method in which the butene pulses were repeatedly injected, the reduction process of the oxide catalysts was investigated in detail. The temperature-programmed reduction and reoxidation were also applied.
The catalysts having an atomic ratio of Sb/Fe higher than the un ity showed a high activity and selectivity for the oxidative dehydrogenation to butadiene. The extent of simultaneous isomerization of 1-butene to 2-butenes was usually small. The reaction rate was approximately of the first order in butene pressure and of the zeroth order in oxygen pressure. The comparison of the results obtained from the flow method with those from the pulse method indicated that the catalyst surface under the reaction conditions of the flow methed was in the oxidation state slightly lower than FeSbO₄.

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The surface properties and states of SnO₂-Sb₂O₄ catalysts were investigated to reveal the promoting effects of the catalyst system. Temperature programmed desorption of oxygen from a series of the catalysts with varying Sb contents (x atomic %) showed that oxygen desorption increased with an increase in x reaching a maximum at x=30% (Fig.1 and 2). The same trend was also observed in the specific activity for the acrylaldehyde formation in the pulse reaction of propene (Fig.4). These results indicate that the catalyst surface is modified properly by the addition of Sb₂O₄ to SnO₂. While X-ray diffraction analysis detected Sb₂O₄ only for x>30% (Fig.5), XPS revealed the surface enrichment of Sb which b ecomes most remarkable at x=20∼30% (Fig.6). The thickness of the Sb-enriched surface layer was estimated to be 20Å or thinner of from SIMS experiments (Fig.7). It is concluded that the active sites of the SnO₂-Sb₂O₄ catalysts are provided by the Sb-enriched surface layer (Fig.8).

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In order to elucidate the mechanism of electrodeposition of gold from tetracyanoaurate(III )complex ions, cathodic current-potential curves was obtained use of a rotating disk electrode and the conductivity and kinematic viscosity of K[Au(CN)₄]-KCN-K₂C0₃ solution were also measured. The slope of Tafel relation was found to be 0.17 V in the potential range of -0.85∼-1.00 V (SCE). The exchange current density io was determined by extrapolating the Tafel relation to the equilibrium potential. The cathodic transfer coefficient a and apparent valence n were also determined to be 0.47 and 0.74, respectively. From the experimental results, the following electrodeposition mechanism was inferred.
Eventually, electrodeposition of gold from tetracyanoaurate(III) ions proceeded through the intermediate dicyanoaurate(I) ions. The diffusion coefficient of Au(CN)₄ - ion obtained from diffusion current density in the solution was 2.44 × 10^-6 cm²/s at 25°C.

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Various fluoride oxides listed on Table 2 were obtained by a high temperature reaction between rare earth fluorides and rare earth or zirconium oxides. The formation of neodymium fluoride oxides and their properties as an electrocatalyst and/or a solid electrolyte used for a fuel cell were studied by means of X-ray diffraction and electrochemical methods. An equimolar mixture of NdF₃ and Nd₂O₃ reacted quantitatively above 1100°Ct o give NdFO under the argon atmosphere. It was found that the crystal structure of NdFO was affected by the reaction temperature and the cooling procedure (Fig.3). Three crystal phases of the rhombohedral, the cubic aiid the tetragonal were identified. The rhombohedral phase was 1-ansformed into the cubic one above 530°C. This transformation was reversible and its enthom measured by the differential thermal analysis was 1.46 kJ/mol (Fig.5).
The cubic NdFO, with a fluorite type structure (Fig.4), was found to be electrocatalytically active for both the hydrogen oxidation and the oxygen reduction. The cubic phase compound, denoted by (NdF0)_0.9(Nb₂O₅)_0.1, which was obtained by the addition of Nb₂O₅ to the cubic NdFO at 1250°C, had the higer catalytic activity and the oxide ion conductivity than N dFO p or t the stabilized zirconia. These neodymiu m fluoride oxides will be useful for a fuel cell as new ceramics having the Characteristics of both a catalyst and a solid electrolyte.

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The initial extraction kinetics of Cr (VI) ion from chromite ore under the hydrothermal conditions of the temperature range: 250 to 420°C, concentration of NaOH solution: 5 mol⋅dm^-3and atmosphere: 20 MPA of O₂ gas, has been investigated. The grain size and shapes of chrome ore were almost kept constant during extraction period, and the initial kinetic curves were examined in consideration of the core-model. The rate of extraction is in good agreement with the following zero-order equation:
where x is the extraction ratio of Cr(VI) ion from chrome ore, k the constant, t the reaction time. Arrhenius plots showed two slopes in the range from 360 to 420°C. The apparent activation energies were found to be about 37.2 kcal⋅mol^-1 in the range of 360∼380°C and 52.8 kcalmo1^-1 in the range of 400∼420°C, respectively. These results showed the existen ce of two different extraction processes. The apparent activation energy of extraction rate of Cr(VI)I ion from the synthesized-MgCr₂O₄ under the same conditions as the case of the chrom e ore was found to be about 14.3 kcal⋅mol^-1. It was suggested that the two extraction processes from the chrome ore were respectively expressed by the following equations:
and that iron and aluminium affected the extraction of chromium as an inhibitors.

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The mercury content was determined for some spring waters collected from areas without recent fumarolic activity (Yashio, Gumma pref.; Boso penin., Chiba pref.; Shiobara, Tochigi pref.; Atsushio, Fukushima pref.; Izu penin., Shizuoka pref. and Northern Tohoku dist., Japan).
Chemical characteristics of spring waters discharged from 72 springs, with pH ranging from 5.4 to 8.8 and temperature ranging from 14.5 to 100°C, showed that they were chloride spr ings (52 springs), sulfate springs (8 springs) and simple springs (12 springs). Mercury contents in those spring waters were from less than 0.001μg/l to 3.5 μg/l. Among those waters, three samples (Atami, Shiobara-Motoyu, Atsushio) contained mercury more than 0.05 μg/l and twenty-five samples contained mercury less than 0.005 μg/l.
The temperature of waters were proved to be importa nt as a factor controlling the mercury concentration. However, there was little positive correlation between the mercury and chloride contents in waters. Particularly, the spring waters containing chloride more than 5 g/l -were characterized by low concentrations of mercury. Ten samples among fifteen waters containing chloride more than 5 g/l contained mercury less than 0.005μg/l.

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Semimethylxylenol Blue (SMXB) forms a reddish-violet 1: 1 complex with gallium at Dptimum pH from 1.3 to 1.7 and its aqueous solution has an absorption maximum at abou t 561 nm. This coloration is applied to the spectrophotometric determination of gallium. The recommended procedure is as follows.
To a sample solution contain ing up to 50 μg of gallium in a 50 cm³ Erlenmeyer's flask, 10cm³ of buffer solution of sodium acetate-hydrochloric acid and 2 cma of 0.1% SMXB solution are added. Then, the volume is made to about 20 cm³ with water. After being kept for five minutes in a boiling water bath, the solution is cooled with running water, transfered to a 25 cm³ volumetric flask, and diluted to the mark with water (the final pH: 1.6). The absorbance is measured at 561 nm against the reagent blank as a reference.
Beer's law is followed over the range of 0.2∼2.0 μg/cm³ of gallium and the sensitivity of the determination is 2.2 × 10^-3μg Gaicm² for 0.001 of absorbance. Of 44 diverse ions examined, aluminium, tin(IV), bismuth(III), scandium, zirconium, thorium, vanadium(V) and iron (III)interfere with the determination. But aluminium, tin (IV), scandium, zirconium and thorium can be masked by the addition of sodium fluoride. The effect of iron(III) is eliminated by L-ascorbic acid and the interference from bismuth(III) and vanadium(V) can be removed by the separation of gallium from these ions by ether extraction.

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The ¹³C-NMR spectra of hydroxyanthrones and naturally occurring anthrones are reported and all chemical shifts are assigned. The calculated chemical shifts using empirical additivity rule agree well with the observed chemical shifts except 9 a, 4 a, 10 a and 8 a carbons. The observed chemical shifts for the anthrones are discussed in relation to charge densities calculated for the system using simple LCAO-MO and CND0/2 method. The chemical shifts are not linearly correlated with π-electron density. On the other hand, the total electron densities calculated by using CNDO/2 method correlated fairly well with the chemical shifts observed.

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On the retention volume in gas chromatography was studied theoretically and experimentally. A linear relationship was derived between the ratios of adjusted retention volume to column length (V_R/Z) and the reciprocals of distribution coefficient (1/K') of solutes between mobile and stationary phases (Eq. ( 9 )) from theoretical considerations based on the regular solution theory and the Van Deemter equation. This relationship was experimentally confirmed by gas chromatography of propylene, butane, 1-butene, 1, 3-butadiene, pentane and isopentane on squalane or Apiezon L supported on fluorocarbons (Flusin-T) (Fig.2∼4) at 30°C and at carrier gas (hydrogen) flow rates of 15 to 50 ml/min. This result suggests that the retention volume for any solute can be calculated from Eq. ( 1 ) if the formation of regular solution is expected between the solute and the stationary phase. In addition, if solutes are nonpolar or nearly nonpolar, it may be permitted that retention volumes were approximately calculated by using equation ( 1 ) for diocty phthalate system which is polar system.

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The thermal reactions of 2-pyrones with several p-benzoquinones gave 1, 4-naphthoquinones and anthraquinones [4] in addition to the Diels-Alder (DA) adducts [1] [3] and [2]. [3]was formed from[1] by elimination reaction (-CO₂, -H₂) and [4] was formed through the reaction of [3]with 2-pyrones.2-Methyl-1, 4-naphthoquinone [3 d] thermally and photochemically gave [2 + 2]cycloaddition dimer [5].
The effects of the substituent in 2-pyrone, re action temperature, and solvents for the formation of the DA adducts were examined. Thus, when p-benzoquinone was used, the DA adduct with 2-pyrone was formed in all the solvents used at 80°C, but that with methyl coumalate was only given in n, onpolar solvents (80, 110°C). The reaction with 4, 6-dimethy12-pyrone proceeded to give [3] or [4] without the formation of DA adduct in all the solvents. The total yields of [1]-[4] were about the same in all the reactions. Namely, DA adducts tend to decarboxylate as increasing the reaction temperature, and polar solvents slow down the DA reactions while accelerate the elimination reaction.2-Pyrone having electronattracting substituent slows down the rate of the decomposition of the DA adduct.

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Solubility to resin, bleeding resistance and light fastness were studied for copolymers of 0.4, 1.02, 2.01, 4.20 and 4.44 mol% N-[m-(methacryloylamino)pheny1]-4-phenylazo-3-hydroxy2-naphthamide[1] and methyl methacrylate. The copolymers with less than 2.01 mol%of the dye showed good light fastness and azo-hydrazone tautomerism similar to compound [1]. The rest copolymers showed poor light fastness. All of the copolymers show ed good solubility to poly(methyl methacrylate) and excellent bleeding resistance.

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To investigate polymeric dyes having excellent bleeding resistance and light fastness, polymeric azo dyes of pyrazolone series were prepared by homopolymerization of 4-arylazo-3methyl-1-[p-(methacryloylamino)pheny1]-2-pyrazolin-5-one, in which the aromatic moieties are C₆H₅, p-CH₃C₆H₄, m-CH₃C₆H₄, p-CH₃C₆H₄, m-CH₃OC₆H₄, p-ClC₆H₄, m-ClC₆H₄, p-NO2CH₄, m-NO2C₆H₄, p-(CH₃)2NC₆H₄.GPC analysis showed that polymeric azo dyes were oligomeric range. It was estimated from IR and NMR spectra that the polymeric azo dyes existed in hydrazone form similarly to the monomeric azo dyes. Light fastness of the polymeric azo dyes in MMA resin cast film was somewhat poor than that of the corresponding monomeric azo dyes, and the fading rate depended on aryl group at 4-position. The polymeric azo dyes, having p-NO₂C₆H₄ or m-NO₂C₆H₄, showed good light fastness. All of the polymeric azo dyes showed good bleeding resistance.

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The study was carried out for airborne particulates which were collected inside a chemical laboratory and on the roof of a building using two Andersen samplers of 8 stages. Geometrical, volume and arithmetic mean diameters of the particulates collected on each stage of the sampler were estimated from both optical microscopic photographs and the secondary electron images obtained by an X-ray microanalyzer. Volume mean diameters of the particulates were about 20% larger than the assigned aerodynamic diameters which were calculated as particle density of 1.0g/cm', and arithmetic mean diameters were about 30% smaller than the aerodynamic, diameters.
The reliablity of particle size distribution curves was also discussed. from comparisons between the curves obtained by different drawers, different drawing methods, and two samplers. Two drawers gave up to 20% differences in the peak position (size) and height (frequency) of the curve using a graphic method. The application of Lagrange's interpolation equations of 4-9 th orders to the curve drawing gave good results except the both terminal regions of the curve, though it gave differences of less than 3.5% to the peak position and height of the curve depending on the order. The differences in the peak position and height were less than 12% between the curves of the particulates collected by two identical samplers. Fluctuations ( σ ) in the values, i. e. frequency, on vertical axis of the curve caused by weighing errors were less than 2.5% of the maximum peak height for 60 mg of a total sample from all stages and less than 4% for 21 mg of a total sample. The size distribution curves of the laboratory particu lates were similar to those of the outdoor particulates, though the former particulates were richer in small ones than in the latter.

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The loss of Cl as HC1 from sea salt particles by air pollutants (NO₃^- and SO₄^2-) in the marine atmosphere was discussed, based on both laboratory experiments and field measurements.
In the laboratory experiments, the release of gaseous HCl from sea salt particles was simulated by passing NO₂ or SO₂ through a filter impregnated with sea water. The release of HCl from the filter occurred by the aeration with NO₂ or SO₂, and the concentration of HClreleased depended on both the concentration of NO₂ or SO₂ and relative humidity. The generation rates of HC1 calcurated from the added amounts of NO₂ and SO₂ were 9% for NO₂and 18% for SO₂ (Table 1 and 2).
The marine aerosol was collecte d by Andersen samplers during January 13-20 and December 14-20, 1981 in the two remote islands, Hachijo-jima and Chichi-jima in order to in vestigate the Cl loss from sea salt in the marine atmosphere. The calcurated Cl losses from sea salt particles ( <2 μm) based on the Cl/Na ratio in sea water (1.8) were 0.21 to 0.36 pg/m³, and 2 to 7% of total particulate marine Cl at the two islands. The Cl loss from sea salt particles smaller than 1 gm was more than 20%, while that from particles larger than 2iam was negligible (Fig.4). A linear correlation was observed between measured SO₄^2- concentrations (<2 μm) and Cl losses, indicating a 1.1 iimol/m³ Cl loss per 1 iumol/m³ SO₄^2- (Fig.5). The HCl concentrations estimated from the Cl losses (5.9×10^-3 to 10× 10^-3, μmol/m ³ ) agreed with the measured HCl concentrations in the marine atomosphere (4.8 × 10^-3 to 15 × 10³, μmolf m³) (Table 5), suggesting that the release salt particles is the main source of gaseous HCl in the marine atomosphere.

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The thermal decomposition of 1, 4-dimethyl-1, 4-diphenyl-2-tetrazene [1] in toluene at 110 °C leads to production of two N-methylanilino radicals with a loss of nitrogen. A part of the nitorogen radicals abstract hydrogen atom from toluene to give benzyl radicals. As a result, N-methylaniline, N, N'-dimethylhydrazobenzene [2], N-methyl-N-phenylbenzylamine [3], aniline, and biphenyl are obtained. The thermal decomposition of [1] was also carried out in the presence of 1-butanethiol as a radical trapping agent in toluene. The yield of [2]decreases with the increasing amount of the scavenger. This means that the decomposition of [1] dods not proceed via a concerted mechanism but by a stepwise one.

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The reaction of resorcinol [1] with. methyl acetoacetate [2] in the presence of 10 mol% of concentrated sulfuric acid has been studied. In addition to the expected 7-hydroxy-4-methylcoumarin [3] as the major product, a small amount of by-product (9.2%) [4] was obtained. The structure of [4] was found to be 7, 7'-dihydroxy-4, 4'-dimethyl-3, 4-dihydro-4, 6'-bicoumarin, a dimer of [3], based on microanalytical data, MS, IR, and NMR spectra of [4]and its bis(ethoxycarbonylmethyl)ether [5]. The plausible mechanism for the formation of [4] is discussed briefly.

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