The promotive transformation for III →V phase in Na₂SO₄ crystals due to the sorption of water vapor was studied under various relative humidities at 25°C. In addition, the effect of a foreign sulfate (Eu₂(SO₄)₃, Y₂(SO₄)₃, SrSO₄, T12SO₄ or Cs2SO₄) on the transformation was investigated under 90% relative humidity at 25°C. The relationship between the fraction of 111IT tiansition and the logarithm of the reaction time was elucidated by the three regions: ( i ) the starting step of the transition with formation of the sorption layer of water vapor on the crystals, (ii) the step of rapid progress of the transition caused by the presence of the saturated sorption layer near the crystal surface, (iii) the final step in which the transition proceeded sluggishly. The promotive action in the III, V transition due to the sorption of water vapor was remarkably inhibited by blending Eu₂(SO₄)₃ or Y₂(SO₄)₃, while the action was accelerated by blending Tl₂SO₄ or Cs2SO₄. The effect of the foreign sulfate on the promotive action was discussed as follows: ( i ) the inhibitive effect on the action was resulted from the formation of a solid solution between Na₂SO₄ and the foreign sulfate, (ii) the accelerative effect on the action was resulted from the epitaxialcy due to the segregation of T12SO₄ or Cs₂SO₄crystal on the grain boundary in Na₂SO₄ crystals.

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  It was found that cobalt(III) ion supported on active carbon (Co³⁺/C) was highly active for the oxidation of normal paraffin at 120°C. Results by atomic absorption/flame spectrophotometry showed that cobalt ion supported on active carbon was insoluble in the reaction mixture. Cobalt(III) acetate was catalytically inactive for the oxidation in water or acetic acid used for impregnation. Cobalt(II) acetate supported on active carbon showed no catalytic activity even at 140°C for the oxidation. These results suggest that the oxidation is not catalyzed by residual solution of cobalt(III) ion in the pore of active carbon but that it is catalyzed by cobalt(III) ion supported on the active carbon.
   In order to elucidate the reaction mechanism, the oxidation catalyzed by Co³⁺/C was studied kineticaly. The oxidation rate was one-half order with respect to the cobalt(III) ion concentration and was independent of oxygen pressure. The apparent activation energy was 17 kcal/mol over the temperature range 107-130°C. The fraction of fatty acids, esters, ketones and alcohols in the product was 3: 3: 3: 1 in molar ratio. These results can be explained by the reaction mechanism which has been proposed for the homogeneous oxidation with metal ions. This suggests that the oxidation mechanism over Co³⁺/C is similar to that of the homogeneous oxidation with cobalt ion. Therefore, the active site of the catalyst was concluded to be cobalt(III) ion on active carbon.

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It was confirmed that mercaptohydroquinone (H₂QSH) reacts with p-benzoquinone to give bis(2, 5-dihydroxyphenyl) sulfide via 1, 4-addition in the Britton-Robinson buffer (20% Et0H)at room temperature. this fact suggests that 1) H₂QSH is electrolytically oxidized to give mercapto-p-benzoquinone, 2) the oxidation product reacts with H₂QSH to form a. dimer, 2(2 5-dihydroxyphenylthio)-6-mercapto-1, 4-benzenediol, 3) the dimer is oxidized further and 4) H₂QSH, SaHd ds successively to the oxidation product of the dimer. Using a glassy carbon electrode (GC) as the working electrode, stable polymers were obtained by electrolytic oxidation of H₂QSH through alternative oxidation and addition reactions on GC both in acidic and neutral media. The behaviors of this polymer electrode were examined by cyclic voltammetry.

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Graphite-nitric acid-intercalation compounds with different stages (from 1 st to 5 th) were prepared by direct immersion into nitric acid with various concentrations. The temperature dependence of the identity period (I_C) was measured by X-ray diffraction over the temperature range +25 to -196°C.
The following results were obtained.
1) Anomalous expansion widths in I. due to the phase transition for the 1 st stage, 2 nd stage and 3 rd-5 th stage were O.025, O.031, and O.045 A, respectively. The phase transition temperature for the 1 st stage was about 10°C, but those for the higher stages and slightly. decomposed samples fell to 1328°C.
2) Another phase transition around 5°C was found from anomalous expansion and from the discrepancy between thermal expansion coefficients above and below 5°C.
3) Thermal expansion coefficients for the 2 nd stage to the 5 th stage at room temperature were a (2 nd) =49.9×10^-6/K, a (3 rd) =43.0 × 10^-6/K, a (4 th) =41.9 × 10^-6/K and r(5 th) =37.0× 10^-6/K.

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In the growth of single crystals from high-temperature solutions, the flux has been normally chosen by trial and error procedures, taking into account of previous experiences. In this study, a guide to the choice of suitable fluxes for the crystal growth of oxides from high-temperature solutions was proposed. In this guide, the criteria were made up by use of some fundamental informations, e. g. ionic radius, melting point, ionicity of chemical bondings, Dietzel's parameter and acidity and basicity. The results on growth ofα-Al₂O₃ single crystals were shown and discussed. A method for growing CaWO₄ single crystals was proposed and the experiment was carried out by using Na₂WO₄ as the flux, which showed that the colorless and transparent CaWO4 single crystals were grown by slowly cooling the high-temperature solution. Also, the growth of NaNd(MoO₄)₂ single crystals was discussed.

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The alteration and leaching process of feldspar were investigated under alkaline hydrothermal conditions with NaOH and Ca(OH)₂ solutions, respectively, at 100-400°C. The crystal structure of feldspar was broken and K₂O component was leached out by hydrolysis of Si-O-Si and Si-O-A1 bonds. Components of SiO₂ and Al₂O₃, however, did not dissolve in Ca(OH)₂solution to form insoluble silicates and aluminates as the residues. The maximum extraction ratio of K₂O with Ca(OH)₂ solution was about 60% under conditions of high temperature (above 300°C) and high contents of Ca(OH)2 in 10 minutes of the reaction time. With NaOtt solution the decomposition of feldspar more easily occurred than that with Ca(OH)₂ solution. The extraction ratio of K₂O attained to 100% under conditions of 200°C, 5 mol·dm^-3 of NaOH concentration and 10 minutes reaction time, while 60% of SiO₂ and several percents of Al₂O₃dissolved into the alkaline solution. The feldspar(SiO₂/Al₂O, molar ratio=6) was changed to analcite(SiO₂/Al₂O₃ molar ratio=4) at 1 mol·dm^-3NaOH concentration, and cancrinite and sodalite(SiO₂/Al₂O₃ molar ratio=2) at 5 and 10 mol. drn-3 NaOH concentration, respectively.

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National Chemical Laboratory for Industry Yatabe, Tsukuba-gun, Ibaraki 305 Japan _Lanthanum silicon triarsenide (F-type), LaSiAs3, crystallizes in the orthorhombic system, space group Pbca, with a=6 084( 1 ), b=5 986( 1 ), c=26 235( 3 ), Åz=8. The single crystals were prepared by cooling the melt slowly from 1000°C under the arsenic pressure of 2.5 atm. The crystal structure was determined from 1272 independent X-ray diffraction intensities by the Patterson method, and refined to R=0.063 by the full-matrix least squares method. It has a pseudo face-centered lattice and is closely related to the layer structure of CeSiP₃ (P-type), [Pn2₁a, a=5.861, b=5.712, c=25.295 Å] previously reported. The layer sequence along c-axis can be described as
[As₂]-[La][Si₂As₄][La]As₂[La]Si₂As₄-La-As₂La-La distance is 4.27 A in the [La] layer. La is coordinated to five As's of the [Si₂As₄]layer in 3.09-3.18 Å and to four As's of the [As₂] layer in 3.20-3.23Å. The As-As distances in the [As₂] layer are 2.99 and 3.04 Å. The [Si₂As₄] layer has the same structure as the corresponding layer of CeSiP₃. In this layer, alternate Si and As atoms form a twodimensional infinite network of six-membered rings with boat conformation, Si-As distances being 2.34-2.37 A. The [As₂] layer seems to have no long range ordering of the zigzag chain which is observed in the CeSiP₃ structure.

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The stereoisomerism of oxo- and thio-bridged dinuclear molybdenum(V) complexes, Mo₂O₂(μ-O, S)(S₂CNR₂)₂[S₁ complex], Mo₂O₂(μ-S)₂(S₂CNR₂)₂[S₂complex], Mo₂O₂(μ-S)₂(S₂CNR₂)₂[S₃ complex] and Mo₂S₂(μ-S)2(S₂CNR₂)₂[S₄ complex], where R is 2-ethylhexyl group, has been extensively investigated by HPLC, UV and IR techniques in connection with the chemical structure of MMo₂O₂(μ-S)₂[S₂CN(n-Bu)₂]₂ which was determined by X-ray crystallography in the previous paper.
On HPLC employing a Zorbax SIL column, the S₁, S₂ and S₃ complexes gave five, five and three separable components, respectively, whereas the S4 complex showed a single peak. Two series of independent equilibrium relation existed among the five components of the 52 complex, one being cis-trans isomerism of the terminal oxygen atoms bound to the molybdenum atoms, and the other being isomerism due to the difference of a dihedral angle between two Mo(μ-S)₂ planes. Therefore, the five components consist of three cis and two trans isomers as shown in Fig.5. The separation of these components by HPLC can be ascribed to the structural difference in the MoS₂XS₂²⁺ cores rather than the variation in alkyl groups.

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This research seeks to clarify the background levels for natural abundance of mercury in gases discharged to the atmosphere from geothermal areas (Shimokita penin. and Hachimantai, Northern Tohoku dist.; Kusatsu-Shirane and Hakone-Owakudani, Kanto dist.; TateyamaJigokudani, Hokuriku dist.; Beppu, Aso, Otake, Unzen and Kirishima, Kyushu dist. ) of Japan and also will provide basic data, to allow comparison with the situation five or ten years later, for the planning to elucidate the acutual conditions of man-made sources.
The amount of mercury discharged from fumarolic gases, bases upon 72 samples taken during 1980-1983, ranged from 0.096 to 1020 μg/m3 with an average value of 75 Atglm3. Mercury contents in steam condensates ranged from 0.08 to 4.8 gel (av.1.3 μg/l) and those distribution values were less than 1400 of mercury discharged from fumarolic gases. The amount of mercury discharged from hot spring gases ranged from O.078 to 6.5 μg/m3 (av.0.75 μg/m3)and the temperature of hot spring waters were proved to be important as a factor controlling the mercury content of hot spring gases. Mercury contents of air in the geothermal areas were ranged from O.045 to 7.3, μg/m3 and those values were 3 to 500 times as large as the mercury content of ordinary urban ambient air. Rough estimate of the volcanogenic con tribution of mercury released to the atmosphere from volcanic gas sources was 5% by analyti cal results of the fumarolic gases. t Studies on Mercury of Hot Springs. III.

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The ligand substitution reaction between the metal acetylacetonates and EDTA was utilized to estimate the amount of metal acetylacetonates by nonaqueous conductometry. DMF or DMSO was used as a solvent because the metal acetylacetonates readily dissolved in the organic solvents, such as DMF, DMSO, pyridine, etc, while EDTA could dissolve in DMF and DMSO only.
The sample solutions were prepared by dissolving the dried metal acetylacetonates in DMF or DMSO. The used metal acetylacetonates were cobalt copper (II), manganese( II), iron (III) and chromiu m (III) acetylacetonates.
The preparation of EDTA solution has been already described in detail. By conductometric titration of metal acetylacetonate with EDTA, the combination ratios between the metal acetylacetonate and EDTA were obtained at the molar ratios of 4: 1, 2: 1, and 1: 1.
These combination ratios were characteristic of the used metal acetylacetonates. These reactivities between the metal acetylacetonates and EDTA were different by the kind of metal acetylacetonate.
The mixture of metal acetylacetonates could be titrated by taking advantage of these differences of reactivity.
Less than 1% of water, inorganic acids and organic solvents such as benzene and chloroform gave no influence on the inflection points in the conductometric titration curves. The determination limits were from 1 x10-4 moledm-3 to 5 ×10^-4 mol·dm^-3 of the metal acetylacetonate. By using these results, determination of Fe (III) after the extraction with acetylacetone was investigated. The results were in close agreement with the those of the extraction photometry.

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A solution of cellulose triacetate in a mixed solvent consisting mainly of dichloromethane and a diluent was suspended into a aqueous medium to form droplets of the above mentioned solution, and then dichloromethane in the droplets was removed by evaporation to obtain cellulose triacetate beads containing the diluent. The beads thus obtained were saponified and the diluent was removed subsequently to prepare porous cellulose bead. The permeability into the porous cellulose bead was determined by eluting water soluble materials such as poly(oxyethylene) through a column packed with the gel and a degree of hydrophobic interaction between gel matrix and sample was measured by eluting methanol and 1-butanol through the column. The porosity of the gels could be controlled by a amount of diluents and a permeable range into the gels was 2000-80000 in molecular weight. The hydrophobic interaction between gel and sample was hardly observed. Measurements of electric conductivity showed that the amount of acidic groups in gels was less than 25 μeq/g. The pressureresistance of the column packed with gel was superior to that of the cellulose gels previously reported. The porous cellulose gels were found to be useful as packing materials for gel chromatography.

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A reaction gas chromatographic technique was applied to the determination of nonvolatile aromatic sulfonic acids and sulfonates. It is based on the desulfonation in a reaction precolumn followed by gas chromatographic determination.
The packing of the reaction column was prepared by coating the Chromosorb W, AW 60/80support with phosphoric acid and the column was used at 250-300°C. The aqueous solutions of benzene-, toluene-, dimethylbenzene-, trimethylbenzene-, ethylbenzene-, chlorobenzene-, dichlorobenzene-, trichlorobenzene-, tribromobenzene-, and 2-naphthalenesulfonic acids and their sulfonates were directly injected into the reaction column.
The volatile aromatic hydrocarbons produced by desulfonation were separated and determined by a gas chromatograph equipped with a flame ionization detector. The reaction column was proved to be durable for a long use, more than 150 injections, without deterioration.
The reproducibility of the chromatograms was satisfactory, and little side reaction products were detected when the concentrations of the sulfonic acids and sulfonates were higher than 10^-3mol/l .

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Graft copolymers, which contain 54, 71 and 84 mol% of pendant poly (vinyl acetate) and whose degree of polymerization were about 2000, were synthesized by grafting vinyl acetate to mannan granules which contained an aqueous solution of potassium peroxodisulfate. Beads of acetylated graft copolymer were prepared by suspending a solution of acetylated graft copolymer in dichloromethane in an aqueous medium.. Then, beads of mannan-poly (vinyl alcohol) graft copolymer were prepared from the beads of acetylated graft copolymer by saponification and subsequent crosslinking. Using columns packed with these beads, exclusion limits and capacity ratios were measured by eluting water soluble materials such as poly(oxyethylene) and ethylene glycol. The capacity ratios and exclusion limits of the gels prepared from mannan-vinyl alcohol graft copolymer were higher than those of poly (vinylalcohol)gels. It was estimated that these behaviors were attributed to the existence of highly hydrophilic micro mannan gel phases in the poly(vinyl alcohol) gel matrix. Consequently, these gels were found to be useful as packing materials for the separation of water soluble oligomers.

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Negative ion chemical ionization (NCI) mass spectra of 31 organochlorine pesticides and related compounds (Table 1) are discussed in comparison with positive ion chemical ionization (PCI) mass spectra for the purpose of revealing their characteristics. Ion abundances of the specific ions are measured by the selected ion monitoring to estimate ion abundance ratios such as negative base peak/positive base peaks and chloride ion peak/negative base peaks. Methane is used as a reagent gas, and ion source temperature and ionization chamber pressure are maintained at 250°C and 0.20 Torr, respectively. The results obtained can be summarized as follows.
1) In general, simple and characteristic NCI spectra based on less fragmentation are obtained for each compounds (Fig.1). Molecular ions, M are mainly generated in aromatic compounds. Fragment ions are primarily consisted of (M-HmCln)-(m≥0, n≥1) and Cl- for all compounds. Pentachlorocyclopentadienide anion, C₅Cl₅-, resulted from retro Diels-Alder reactions are characteristic for chlorinated dimethanonaphthalenes and methanoindenes.
2) Base peaks (above m/z 100) in NCI and PCI spectra have many varieties (Table 2), and the ion abundance ratios of negative/positive ions ranged from several to several hundred, indicating that highly sensitive detections are possible by the NCI method.
3) Chloride ions, Cl are generated in wide range of magnitude (Table 2), and the ion abundances are frequently more abundant than those of negative base peaks.

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Public Health; Shirokanedai, Minato-ku, Tokyo 108 J In Negative ion chemical ionization (NCI) mass spectra of 36 nitroarenes (Table 1) are measured in comparison with positive ion chemical ionization (PCI) mass spectra for the purpose of revealing their characteristics, and also ion abundance of negative and positive base peaks are measured by selected ion monitoring to estimate their ion abundance ratios. Methane is used as a reagent gas, and ion source temperature and ionization chamber pressure is maintained at 250°C and 0.20 Torr, respectively. The results obtained can be summarized as flloows.
1) Ions generated in NCI consist mainly of (1) molecular ions, M^-(2) fragment ions, (M-HxNyOz)^- (x≥0, y≥0, z≥1) such as (M-O)^-, (M-NO)^-, (M-NO₂), and NO₂^-, (3)adduct ions, (M+CH₃)^- and (M+C₂H₅)^-, and quasi-molecular ions, (MH)^- (Table 2). Molecdfai: ions become base peak except for the case of 2, 2'-dinitrobiphenyl (Table 3). Fragment ions are similar to the ions of PCI.2) Ion abundance ratios of negative base peak/positive base peak ranged from several to one thousand indicating that highly sensitive detections are possible with NCI method (Table 3).

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Magnesium salts of ethylenethiourea [1a], 1, 3-dimethylthiourea [2 a], trimethylthiourea [3 a], 1, 3-dibutylthiourea[4 a], and 2-methylthio-2-imidazoline [5 a] captured carbon dioxide and the resulting CO2-adducts [ 1b], [2b] and [3 b] released almost quantitatively the captured CO₂ at room temperature in DMF except for [4 b] and [5 b]. The adducts [ 1b], [2b] and [3 b] transfered the CO₂ moiety easily to active methylene compounds such as indene, cyclohexanone, acetophenone, and 1-tetralone at room temperature under nitrogen atmosphere to give the corresponding carboxylic acids in good yields. However, [4 b] and [5 b] did not work effectively as CO₂ carrier. The potassium ethylenethioureide-CO₂ adduct underwent slight decarboxylation, but was ineffective as a carboxylating reagent. These experimental findings suggest that the C=S bond of the thioureas and the magnesium ion play an important role in the transcarboxylation process.

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The qualitative and quantitative analyses of polar fractions in distillable liquid from Wandoan coal hydrogenation product have been carried out on a Hewlett-Packard 5880 A GC and a Hewlett-Packard 5992 A GC/MS equipped with a fused-silica capillary column (50 m × 0.2 mm)coated with cross-linked methylsilicone. From the distillate (180-420°C) of the coal liquid were separated three polar fractions, acidic, basic and neutral polar fractions.
As shown in Fig.1 and Table 3, the acidic fraction was mainly composed of alkylphenols (76%) and alkylindanolsfalkyltetrahydronaphthols (12%). Since FID gas chromatogram of the basic fraction (Fig.2) was similar to that of NPD, all components in this fraction were concluded to contain nitrogen. As shown in Table 4, this fraction consisted of pyridines, anilines, quinolines, tri- and tetracyclic nitrogen compounds and their hydrogenated compounds. NPD gas chromatogram of the neutral polar fraction showed that the nonbasic nitrogen components, indoles and carbazoles, were contained. Some components of the acidic and neutral polar fractions were observed by FID gas chromatography to overlap each other. The phenolic components with fewer alkyl carbons were in the acidic fraction and the ones with more alkyl carbons were in the neutral polar fraction.

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The racemic structure of DL-a-phenylglycine (DL-Phg) sulfate has been studied. DL-Phg sulfate forms a racemic compound at temperatures in the vicinity of the melting point, and the value of free energy of formation of the racemic compound is negative. However, it is suggested that the racemic compound becomes unstable with a decrease in temperature, since the enthalpy is positive. In the solubility ternary phase diagrams in 30 wt% H₂SO₄, the solubility curves at 10 and 20°C showed characteristic patterns of racemic compounds, while those at 0 and 5°C patterns of conglomerates. DL-Phg sulfate crystallized from a 30 wt%H₂SO₄the solution at 0°C showed an infrared spectrum identical to that of D-Phg sulfate, but the spectrum was different from that of DL-Phg sulfate crystallized at 20°C. It was possible to resolve DL-Phg sulfate by preferential crystallization procedure in 30 wt% H₂SO₄ at 15°C. These results indicate that DL-Phg sulfate forms the racemic compound at temperatures higher than 10°C and is conglomerate at temperatures lower than 5°C.

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In the uncatalyzed polymerization, it was realized that the initiation reaction took place through a hydrogen transfer, as shown in Scheme 1 (in Text). The radicals [1] and [2] were caught by the spin-trapping method. In order to support the mechanism, perturbation energies, ΔE, of the hydrogen transfer reaction between acrylonitrile (AN) and the complexes of AN with Lewis base were calculated by Frontier Electron MO method. As the models of the macromolecular anion or Lewis base, HCOO-:, CH₃COO-: and (CH₃)₂O: were applied. The calculations were carried out by the ab initio Hartree-Fock (STO-3 G basisset)method. ΔE of the hydrogen atom transfer reaction from AN to AN, from HCOO: … AN to AN, from CH₃COO:… mAN to AN, and from (CH₃)₂O:… AN to AN were 0.003, 0.030, 0.029 and 0.029 eV, respectively. By complexing of AN with Lewis base, the energy levels of MOs of AN raise. Accordingly, the σ-HOMO of the complex becomes to go near to the π*-LUMO of the free AN. And tIE becomes thus larger and the hydrogen transfer from the complexed AN to a free AN may proceed.

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Kinetics of radical polymerizations of methyl methacrylate (MMA) and styrene in carbon tetrachloride (CCl₄) were investigated. It was determined that the kinetic orders of MMA and styrene were 1.2 and 1.3, respectively, which were contrary to the expectation of the viscosity effect on the basis of termination reaction. It was found that the effect of CCl₄on the kinetic of the polymerization was not caused by either the primary radical termination or the degradative chain transfer. The propagation rate constant (k_p) and the termination rate constant (k_t) were determined by the rotating sector method. The kp values of both MMA and styrene changed little and there was no important role of CCl₄ in the propagation step. The kt values decreased with an increase in the CCl₄ concentration anti-proportionally to the viscosity of the system. The rate of initiation (R₁) decreased with the increase in the CCl₄ concentration and the decrease was found to make the kinetic order of monomer larger than unity.

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Sodium salts of dialkyldithiocarbamates (R₂NCS₂Na) and hetero-ring-containing dithiocarbamates were subjected to capillary tube isotachophoresis to study the effects of substituents to their electrophoretic behaviors. (n-Pr)₂NCS₂Na and (i-Pr)₂NCS₂Na were found to have the same mobility and similar evidence was also observed in the case of (n-Bu)₂2NCS2Na and (n-Bu)₂NCS₂Na. Sodium 4-morpholinecarbodithioate, containing an oxygen and a nitrogen atom in the ring, showed mobility larger than expected from its molecular weight.

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