The thermal conversion routes of Mo2S₂(μ-S)2L2 (S4 complex), where L is S₂CN(2- ethylhexy1)₂, were investigated quantitatively by HPLC. The S₄ complex was converted by heating in air to Mo₂OS(μ-S)₂L₂ (S₃ complex) and MoO(S₂)L₂ (compound [1]). Compound [1] was further decomposed to HPLC-nondetectable compounds via MoO₂L₂ (compound (2)). The S₃ complex was converted simultaneously to Mo₂O₂(μ-S)₂L₂ (S₂ complex), Mo₂0₂(μ-O, S)L₂ (S₁ complex), compound [1] and compound (3). The S₂ complex was formed via compound [3] as well as directly from the S₃ complex. The S₁ and S₂ complexes were stable compared to the S₃ and S₄ complexes. The Si complex was not produced from the S₂ complex. In air oxidation the terminal sulfur in the S₄₂ complex was found to be replaced more easily to oxygen than the bridged one.

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The determination of 2- and 4-aminopyridine in environmental water and sediment samples was studied. Aminopyridine(AP) was acylated with N-(pentafluropropionyl)imidazole and determined by a gas chromatograph with an electron-capture detector (GC-ECD). To 200 ml of water sample, 4 ml of 1-butanol, 76 g of sodium chloride, and 4 ml of 25(w/v)%-sodium hydroxide solution were added and APs were extracted with ethyl acetate(100 ml x 1 and 50 m/ x 2). The extract was concentrated to 2 ml. A 1 ml portion of the extract concentrated was placed in a vial bottle(5 ml), and then mixed with O.25 ml of concentrated hydrochloric acid-methanol(1/3)solution. After dryness in a stream of nitrogen, APs were derivatized with N-(pentafluoropropionyl)imidazdle(0.1 ml) by heating at 85°C for 1 h. Pentafluoropropionylated APs were extracted with benzene and washed with water. The extract was transferred to a 5% hydrated silica-gel column(10 mm I. D. x 100 mm) and eluted hexanebenzene(1/2). The first 60 ml of eluate was discarded the next 120 ml of eluate(containing 2-AP) was collected and concentrated to 10 ml. After 50 ml of hexane-ethyl acetate(3/1) solution was eluated, the next eluate, hexane-ethyl acetate(1/1)solution, was collected for 4-AP and concentrated to 10 ml. A sediment sample(10g) was mixed with 100 ml of water and O.1 ml of hydrochloric acid and APs were extracted by shaking for 30 min. The aqueous extract was filtrated, neutralized, and treated in the same way as the water sample. The sample extract was measured with the GC-ECD using a glass column(2 mm I. D. x 1.8 m), into which Gaschrom Q (100-120 mesh) coated with 5% FFAP was packed at the column temperature of 120(2-AP) and 160°C(4-AP). The detection limits of 2-AP and 4-AP were 0.13 and 0.6 pgll for water samples, respectively, and 0.0025 and 0.012 figig for sediment samples. The recoveries of 2-AP from river water, sea water, and sediment samples were 80.1, 69.1, and 58.0%, respectively and for 4-AP they were 89.8, 46.8, and 55.7% (Table 1).

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In the present study, conductometric titration of elementary sulfur with potassium permanganate in pyridine was studied. Elementary sulfur and potassium permanganate were well dissolved in pyridine.
Pyridine solution of potassium permanganate was stable about 10 days and could be used as a standard solution. The permanganate solution was prepared by the ordinary method which was carried out in aqueous solution. Elementary sulfur was slowly oxidized with potassium permanganate in pyridine. Excess of potassium permanganate added to the elementary sulfur solution and elapsed for 30 minutes at about 50°C, and then, unreacted potassium permanganate was titrated with pyridine solution of selenous acid conductometrically. Titration was carried out at the speed from 0.5 cm³.min^-1 to 1.0 cm³.min^-1 at about 20°C.
It was found that the reaction ratio of elementary sulfur and potassium permanganate was observed at 1: 2 from the inflection point. The equation was presumed as
S + 2KMnO₄→K20 + 2MnO₂ + SO₃
The experimental results of this method for commercial elementary sulfur agreed with the results of the bomb or JIS K 8088 method.
Mixed solution of elementary sulfur and hydrogen sulfide or thiophenol were studied by iodometry and permanganometry in pyridine.
As the results, hydrogen sulfide and thiophenol was determined by iodometry and observed reaction ratio of hydrogen sulfide to iodine was 1: 1 and thiophenol to iodine was 2: 1. Coexistence of elementary sulfur gave no influence on iodometry. Total amount of ele- mentary sulfur and sulfur compounds was determined with permanganometry. Less than 1% water gave no influence on the method.

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Composite beads were synthesized by suspending dichloromethane solution of poly(vinyl alcohol) ester and cellulose ester mixture in aqueous solution of poly(vinyl alcohol) and evaporating the solvent. Then porous poly(viny alcohol) gel beads were prepared from the composite beads by saponification, crosslinking with epichlorohydrin and the subsequent removal of cellulose. In order to change the state of phase separation of two components in the beads, kinds of poly(vinyl alcohol) esters and cellulose esters, and ratio of components were varied. The degree of bulkiness, capacity ratio and molecular weight at exclusion limit increased remarkably by the removal of cellulose from composite gels. Molecular weight at exclusion limit of poly(vinyl alcohol) gels prepared from poly(vinyl acetate)/ cellulose acetate butyrate or poly(vinyl propionate)/cellulose acetate butyrate composite systems were up to 2 x105 in molecular weight of poly(ethylene oxide).
Molecular weight at exclusion limit of poly(vinyl alcohol) gels prepared from other composite systems were lower than those prepared by the above mentioned procedure. Consequently, the porous poly(vinyl alcohol) gels were found to be useful as hydrophilic packing materials for high performance gel chromatography.

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Acrylamide, N, N'-methylenediacrylamide and methacrylamide were suspended in petroleum hydrocarbon and copolymerized to give spherical porous gels in the presence of mixture of water and ethanol as a diluent. The cumulative distribution curves of the pore diameter were obtained by eluting water soluble materials, such as ethylene glycol oligomers and poly(ethyleneoxide), through a column packed with the gels.
The increasing proportion of the number of moles of methacrylamide to the number of moles in all monomer were resulted in the increase of exclusion limits. In the molar ratio of methacrylamide to acrylamide was 0.168, exclusion limit of, degree of swelling(wet-ml/ dry-m/) of, and amount of water regain(g/dry-g) of the gel were 4.1 x 104, 4.15, and 3.59, respectively. On the other hand, in the molar ratio of methacrylamide to acrylamide was O.834, exclusion limit of, degree of swelling of, and amount of water regain of the gel were 2.8 x 105, 3.77, and 3.05, respectively.

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This report deals with the iodimetric titration of metal hydrides (CaH₂, LiH, LiAlH₄, NaH and NaBH₄) using pyridine solution of sulfur. By adding small amount of waier in pyridine solution of sulfur dispersing a metal hydride, nascent hydrogen is generated and reacted with dissolved sulfur by forming -SH compound. The -SH compound is titrated with pyridine solution of iodine potentiometrically using a Pt-Ag bimetallic 'electrode. After taken a metal hydride about from 10 mg to 20 mg in the titration cell, added 40cm³ of pyridine solution of sulfur (0.2 mol.dm^-3) and 15cm³ of pyridine solution dissolving about 10% of water, and then, elapsed for 30 minutes at about 50°C. Titration rate was 1.0 cm'. min-' at room temperature.
In the case of LiH, LiA1H₄ and NaH, NaOH or LiOH which produced during the reaction gave a large amount of positive error on the iodimetric titration but the titration could be carried out by removing of the interference with boric acid dissolved about 20% in N, Ndimethylformamide about 5 times of a metal hydride.
NaBH₄ gave an inflection point at a molar ratio of 2: 1 with iodine by direct conductometric and potentiometric titration in pyridine. Visual titration could be carried out using Methylene Blue as an indicator also Less than 10% of water gave no influence on the iodimetric titration of NaBH₄.

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Methyl 2-pyrone-5-carboxylate[1] readily reacted with an electron-rich olefin such as ethyl vinyl ether at room temperature to give a quantitative yield of a [4+2]cycloadduct [2]. The activation energy was estimated to be 13.7 kcal.mol-1. However, the reaction of [1] with an electron-deficient olefin such as acrylonitrile took place only under irradiation in the presence of sensitizers (ET≤59 kcal.mol-1) to afford two types of [4+2]cycloadducts, [3] and [4], together with a poor yield of [2 +2]cycloadduct [5]. The structures of these thermally stable adducts, [2] to [5], were assigned as follows. [2] and [3]: methyl endo-8-substituted 3-oxo-2-oxabicyclo[2.2.2]oct-5-ene-6-carboxylates; [4]: an exo isomer of [3]; [5]: methyl endo-7-cyano-3-oxo-cis-2-oxabicyclo[4.2.0] oct-4-ene-6-carboxylate.
The sensitized photoreaction of [1] with dimethyl acetylenedicarboxylate or phenylacetylene gave 1, 2, 4-tris(methoxycarbonyl)benzene or methyl m-phenylbenzoate, respectively, which has been formed through the decarboxylation of the corresponding [4+2]adduct.

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The reaction conditions for the ring transformation of 4-phenyl-3, 5-bis(methoxycarbonyl) isoxazoline 2-oxide [1c] with Lewis acids such as TiCl₄ etc. were examined to obtain more favorable results. The reaction was applicable to the ring transformation of 4-(1-naphthyl) isoxazoline 2-oxide derivative [1a] to afford preferentially 3 a, 4-dihydro-5 aH-naphtho [1', 2' 4, 5] furo[3, 4-d] isoxazole-3, 4-dicarboxylate [2 a] in a yield of 55%. The scission of N-0 bond in the presence of Raney Ni-acetic acid under a hydrogen atmosphere gave [4] and lactone [5] of [4]. The diamide[7], dibromide [8], and dihydro adduct [9] were also derivated from [2a].

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Common salt effects on the ring-opening reactions of propylene oxide (PO) with dichloroacetic acid (DCA) were studied kinetically in aprotic solvents, dioxane, monoglyme, diglyme, toluene, and acetonitrile. Potassium and cesium dichloroacetate used as common salts were dissolved into the solvents by complexing with 18-crown-6 (18 CR 6). In each reaction system except for int-the reaction in acetonitrile the ring-opening of PO was found to obey the following kinetics,
v=k3(a-x)2(b-x)+k3'C0(a-x)(b-x)
where a-x and b-x were the concentration of DCA and PO at time t, respectively, and the second term on the right hand was based on the reaction in the presence of the initial concentration Co of common salts. In toluene the PO-DCA reaction in the presence of potassium salt was carried out in the same concentration of 18 CR 6 as that in the absence of the salt, because the reaction was retarded by adding only 18 CR 6 into the reaction mixtures. The PO-DCA reactions were accelerated to a considerable extent in the presence of the common salts. For example, the rate constants k3 (l2/mol2.s) and activation parameters (ΔH* (kcal/mol) and ΔS* (e. u.)) at 40°C for the PO-DCA reactions in the absence of potassium salt were 0.763 x 10-5, 13.4 and-39.2 in dioxane, and 2.51 x 10-4, 11.3 and -37.0 in toluene containing 18 CR 6 (0.456 mol/l). The constant k3' (l2/mol2. s), activation enthalpies (kcal/ mol) and activation entropies (e. u.) at 40°C for the reactions in the presence of potassium salt were 2.29 x 10-3, 19.8 and -7.3 in dioxane, and 7.95 x 10-3, 15.9 and -17.5 in toluene. The acceleration of the reactions in the presence of the common salts could be accounted for by the activation entropies rather than the activation enthalpies. In acetonitrile the kinetic study of the PO-DCA reaction in the presence of potassium salt was difficult because there was no linear relationship between the apparent second-order rate constant and the initial potassium salt concentration.

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Department of Applied Chemistry, Faculty of Engineering, Osaka City University; Sugimoto, Sumiyoshi-ku, Osaka-shi 558 Japan Noncatalytic reaction of Solvent-refined Coal derived from Gulf-SRC with tetralin was studied at temperatures of 400 to 470°C and pressures of 20 to 60 MPa by continious flow method. Liquefied products were analyzed by TLC-FID method into mixtures of compounds as classified as preasphaltenes, asphaltenes, and oils, and yield-time profiles with these classes of fraction were obtained. These profiles were the same tendency under our experimental conditions as shown in Figs.1, 2 and 3. The adequacy of two simple kinetic models on the yield-time curves was checked. The model involving a direct path from preasphaltenes to oils was somewhat reasonable for our experimental data. Rate constants estimated by the applicating this kinetic model showed that the reaction from asphaltenes to oils was more accelerated than other reaction with increasing pressure. Activation parameters were evaluated and were compared with those in literature. Effects of pressure on the dehydrogenation of tetralin to naphthalene and on the isomerization of tetralin to 1-methylindan were also discussed.

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The qualitative and quantitative analyses of nonpolar distillable products derived by the liquefaction of Wandoan coal in toluene have been carried out by GC and GC/MS equipped with a cross-linked methyl silicone capillary column(50 m x 0.2 mm). Many low boiling compounds produced from Wandoan coal in toluene were identified by the GC analysis of the total liquid product. (Table 1) The results showed that alkylbenzenes, phenols and normal paraffins were the main components and polyfused aromatic compounds were present in minor amounts (Fig.1). Nonpolar distillates (180-420°C) were separated into four fractions by HPLC. By the GC and GC/MS analyses of each fraction, many minor components such as olefins, (normal alkyl)benzenes and dibenzofurans were identified. As shown in Table 6, normal paraffins and naphthalenes were major components in nonpolar distillate and phenan- threnes and pyrenes/fluoranthenes were minor.

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Coal-derived distillate of Akabira coal was separated into various fractions of hydrocarbons (Fr-P, M, D 1, D 2, T) using HPLC equipped with a Zorbax BP-NH₂ column as reported previously. Oxygen- and nitrogen-containing compounds remaining in the distillate were subsequently separated into three polar fractions (Fr-B, N, A) in a stepwise elution system with different concentrations of solvents from n-hex4ne to chloroform (Fig.3). To examine the HPLC separation behavior for the polar compounds, the character of each fraction was clarified by means of IR spectra (Fig.4) and by GC equipped with a flame thermionic detector (FTD) or FID for nitrogen compounds (Fig.5, 6, 7). GC-MS techniques were employed to identify the individual components of each fraction. The results of the analyses showed that the Fr-B was mainly composed of basic nitrogen compounds such as tetrahydro- quinoline and its alkyl derivatives (Table 1). Fr-A was composed of acidic oxygen compounds such as phenol and its alkyl derivatives (Table 3). On the other hand, the major compounds of Fr-N were alkylcarbazole and alkylphenol (Table 2). These results show that the polar compounds were separated into three fractions according to their polar characters, although some cross-contamination was observed.

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The aroma of odorants solubilized in surface active agents can be different from that of the original blend and therefore the subject of great interest among perfumers and flavorists. To disclose the effect of micelle formation and mechanism of solubilization, the electric conductivity, transference number and osmotic pressure have been measured for the dispersed system of micelles of sodium dodecyl sulfate (SDS) containing geraniol or geranyl acetate at 30°C. The experimental results showed that the number of micelles in the dispersed system increased in proportion to the amount of added geraniol until geraniol molecules filled the palisade layer of the mixed micelle and excess of geraniol molecules over its solubility limit in the layer were solubilized into the hydrophobic zone of the micelle. The partial vapor pressure of odorants solubilized in the micelles was calculated from the amount of aroma of the dispersed system, collected by the sweeping method. When geraniol was solubilized in SDS micelles, the aroma of odorant became weak, since its partial vapor pressure was restricted by the molecular interaction in the palisade layer of mixed micelles and further by the association of geraniol molecules in the hydrophobic layer. On the other hand, when geranyl acetate was solubilized in the micelles, its aroma was not so much weak, since its partial vapor pressure was increased by the weakened molecular interaction in the hydrophobic layer of SDS micelles.

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Induced optical activities of dyes bound to biopolymers have been studied over 20 years, and most of such systems were anionic biopolymer complexes. As one of our recent studies on the chiral interactions between cationic biopolymers and dyes, induced circular dichroism (CD) of the complexes of clupeine sulfate, which contaips about 70% arginine in its primary structure, with anionic azo dyes is reported here. Two dichroic bands associated with the blue-shifted absorption peaks of dyes were observed in the visible wavelength region by complex formation at pH 5∼9. The induced CD arose from the dyes bound to clupeine in random-coil structure. Based on the characteristic CD features of the complexes, the preferential interactions between clupeine and dyes were examined by the induced CD spectra. The dye, which led to the preferential complex formation, was in the order of Congo Red>Orange I>Methyl Orange. The induced CD method seems to have great promise as a facile technique to investigate the preferential interaction between biopolymers and low molecular weight compounds. The results obtained were discussed in comparison with the poly(L-arginine) sulfate-MethylOrange"complex.

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As degree of dissociation and comformation of polyelectrolytes is dependent upon hydrogen ion concentration, many kinds of polyelectrolyte complexes (PEC) are prepared by mixing [2-(diethylamino)ethyl]dextran hydrochloride (EA) with the mixure of (carboxymethyl)- dextran (CMD) and poly(vinyl sulfate) (PVSK) at various concentrations of hydrogen ion and in different orders of mixing.
Elemental analyses, IR spectroscopy, colorimetric reactions with Toluidine Blue and solubilities of PEC have revealed that PEC's in this study are classified into three groups according to their structures and properties. First, the group of PEC prepared in concentrated acidic solution, and are composed almost of EA and PVSK connected by ionic bonding with each other. Second, those in the solution of higher pH, which are made up of EA, CMD and PVSK ionic bonding with one another. Third, the group of PEC formed in the solution of lower pH, which are also constituted of EA, CMD and PVSK. The states of bonding among each component, however, are more complicated than those in the preceding group.

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Foam separation experiments were carried out to study adsorptive characteristics of the ethylhexadecyldimethylammonium bromide(EHDA-Br)-phenol system in alkaline solution at pH 12, 25°C. The surface excess C6H₅O- ion, Γz, and the surface excess EHDA+ ion, Γx, were measured with the concentration of phenol (Zb) varying from 6 x10-5 to 9 x10-4 mol.dm^-3 and of EHDA-Br (Xb) from 7 x10-6 to 4 x10-4 mol.dm^-3. Γz-increased with the increases of Zb and Xb at lower concentration and rz tended to be constant at higher concentration, while r, was virtually independent of Zb and the effect of Xb on Γx was the same as that of Xb on Γz. The adsorption isotherms of both EHDA + ion and C6H₅O- ion were well expressed by the Langmuir equation. It was presumed that the formation of ion pairs occurred at the gas-liquid interface between EHDA + and Br^-, OH- or C6H₅O-. Since the ratio of the surface excess C6HSO- at complete coverage in monolayer, Γz*, to Γx was equal to 1.0, the formation of ion pairing between one phenolate ion and each EHDA cation was verified.

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In the presence of inorganic anion, many heavy metal ions are known to be, adsorbed on activated carbon as either [MX4]2- anions or reduced forms. In this paper, the effect of Br^- (or SCN-) concentration on the adsorption of Cd²⁺ on activated carbon was investigated in connection with the amount of [CdXn] (X=Br^-, SCN-) complexes existing in equilibrium solution. The amount of adsorbed Cd²⁺ was analyzed with Langmuir's 41sorption isotherms.
The amount of residual Cd²⁺ showed a minimum at the concentration of Br^-, (or SCN-) about 0.4 mol/l at which the distribution of [CdX2] or [CdX3]- complexes were maximum (Fig.2). The Langmuir's isotherm showed a good linearity at a constant Br^- (or SCN-) concentration (Figs.3, 4). The saturated adsorption capacities obtained from the intercept of the adsorption isotherms were constant for the same activated, carbon even if the concentration of Br^- (or SCN-) changed (Table 2), and the adsorption equilibrium constants for [CdX2] and [CdX0]- were obtained by the analysis of the slopes of adsorption isotherms using Equation (3) (Table 3, Figs.5, 6). The calculated values of residual Cd²⁺ from Equation (4) using these equilibrium constants are in fair agreement with the experimental values on adsorption of Cd²⁺ in the presence of Br^- (or SCN-) (Fig.7). From these results, it is concluded that [CdX2] and [CdX3]- (X=Br^-, SCN-) complexes play an important role in the adsorption of Cd²⁺ on activated carbon.

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The effect of proton donors on the electrochemical reduction of 2, 3-disubstituted 1- indenones (IDO) in N, N-dimethylformamide containing 0.1 mol.dm^-3 n-Bu₄NBF₄ has been investigated. Kinetic study of the reaction of electrolytically generated IDO anion radical with hydroquinone was performed by DC polarography. The results indicate that the IDO in the presence of hydroquinone is reduced via the ' ECE rnechanism ° and rate law is given as -d[IDO']/dt=k[IDO-][Hydroquinone]. The activation parameter was also determined. A good linear correlation of the rate constant, k was observed to Hammett substituent constant, Σσp=σ1-1-0.5σ, for the 2, 3-diaryl-1-indenones, [1]∼[11] or Taft polar substituent constant, Σσ*=σ1* +0.5 σ2* for [1], the 2-aryl-3-alkyl-, [12]∼[16], and the 2-alkyl-3-aryl-1-indenones, [l7], [l8], respectivery.

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The acid-catalyzed rearrangement of 4, 4'-disubstituted azoxybenzenes is generally regarded to give the corresponding o-hydroxy azo compounds as main products. However, 4, 4'- dimethylazoxybenzene gave 3-chloro-4, 4'-dimethylazobenzene (14%), 4-chloromethy1-4'- methylazobenzene (21%), and 4, 4'-dimethylazobenzene (30%), when treated with excess AlCl₃ in nitromethane at 100°C for 4 h. The formation of expected 2-chloro-4, 4'-dimethylazobenzene was not observed. Similarly, the treatment of 4-methylazoxybenzene (a mixture of the NNO and ONN isomers) with AlCl₃ in nitromethane gave a mixture of 3-chloro4-methylazobenzene (9%), 4-(chloromethyl)-azobenzene (20%), 4-chloro-4'-methylazobenzene (24%) and 4-methylazobenzene (27%).

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The reaction of 2-(3 chloro-4-methylbenzoyl)benzoic acid [1] in polyphosphoric acid at 100-140°C gave 2-chloro-3-[3-chloro-2-methy1-10-oxo-9(10 H)-anthrylidenemethyl]anthraquinone [4] along with 1-chloro-2-methyl- and 2-chloro-3-methylanthraquinones [2] and [3]. Only [2] and [3] were formed at 75°C. The structure of [4] was determined based on its MS; -IR.; 'NMR and UV spectra and its chemical behavior. Mechanism for the formation of [4] is discussed.

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The minerals, from which Li+ and K+ had been extracted in high extraction ratios, had high adsorbability of Sr²⁺ and Cs⁺ ions. Hydrothermal extraction residues of lithia-mica and, feldspar had high distribution coefficients (10³∼40⁴) towards Sr²⁺ and Cs⁺ ions in the aqueous solution. Although the red mud prepared from bauxite had high distribution coefficient of Sr²⁺ ion, it had low distribution coefficient of Cs⁺ ion.
These iesidues' obtained by the hydrothermal treatment of aluminosilicate ores are expected as the promising immobilization matrix of ⁹⁰Sr and ¹³⁷Cs found in the nuclear fission wastes.

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