The polarized absorption spectrum of benzil was measur ed in the stretched polymer film at 101 K. MO calculations were carried out by the modified PPP method, in which the interactions between the nonbonding electrons and π-electrons and those between the two π-electron systems being almost perpendicular to each other were taken into account. Benzil, shows three ππ bands at 296nm, 263.5nm and 256nm, and three nπ, bands at 382.0nm, 334nm and 228nm. The intensity of the nπ* band at 228nm is considerably great compared with those of 382nm and 334nm bands. This is explained by the intensity borrowing derived from the torsion of the molecule. From the observed- and calculated results, the torsion angle between the two carbonyl groups is estimated to be about 75°.

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Choloride ion content in freshly prepared concrete was evaluated by chlonoamperometric method. A square-wave voltage was applied to the small silver electrode and the anodic current, generated by a formation of silver chloride at the electrode was measured. Fresh concrete was prepared by mixing ordinary portland cement, mineral aggregate, admixture and water, in which reagent-grade sodium chloride was added, to make a fresh concrete of the desired chloride ion concentration (0-1% NaCl as weight). The silver electrode was immersed into cement pastes or its supernatant solutions containing sodium chloride and the current in both media was measured. It was found that the currents obtained both in the paste and in the solution depended on chloride concentration, and variation of coefficient of the current was smaller for the supernatant solution than for the pastes. A comparative study using the Volhard titration method showed that the chlonoamperometric method works as well in slush concrete as in an aqueous chloride solution. No interference from the admixture was observed.

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Langmuir type adsorption of 1, 1, 1, 3, 3, 3-hexafluoro-2-propanol (HFIP) on metal oxides, such as Nb₂0₅, TiO₂, Si0₂, γ-Al₂0₃ and MgO, took place when HFIP vapor came into con-tact with metal oxide powders at 50°C in a closed system (Fig.2). The amounts of HFIP adsorbed on the metal oxides increased with an increase in isoelectronic point (IEP), or basicity of the metal oxides (Table 1). Pretreatment with NH₃ enhanced the adsorption of HFIP on Si0₂. Occupation areas of HFIP molecules on various metal oxides were calculated to be 63-98 A² (Table 2).
IR spectra showed th at HFIP adsorbed on Si0₂ or MgO was not perfectly removed even at 400°C. The MgO surface became hydrophobic by the adsorption of HFIP. On the other hand, the surfaces of MgO and r-Al₂0₃ also became lipophobic by the adsorption (Fig.7).

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ZSM-5 zeolites were synthesized with Si0₂/Al₂0₃ of which molar ratio were varied from 70 to 3300. The catalyst activity for conversion methanol into hydrocarbons at 400-600°C and their physicochemical characterization were studied on these ZSM-5 zeolites. The reaction was carried out using an atmospheric pressure fixed bed fl ow reactor at LHSV =2.3 h_-1 from 400 to 600°C. Fig.1 shows the results of methanol conversion into hyd-rocarbons on ZSM-5-70-3300 zeolites. From Fig.1 it was found that the catalyst activity was decreased with increasing Si0₂/Al₂0₃ ratio and 'the deactivation easily took place on these zeolites above 500°C. On the catalyst of low Si0₂/Al₂0₃ ratio, methanol completely converted into hydrocarbons below 500°C, but the catalyst activity decreased above 500°C. The yield of light olefins increased with increasing Si0₂/Al₂0₃ ratio, or raising the reaction temperature to 500°C. The maximum (C₂=+C₃=) selectivity was 44% on ZSM-5-200-400. Further, these zeolites were characterized by determining BET surface area, the particle size by SEM, and the acid property by the methods of NH₃-TPD and FT-IR (Table 1). On the other hand, coke contents of these catalysts were measured after the reaction. Each of these zeolites showed a considerable tendency for coke formation. ZSM-5-1100showed the comparatively smaller coke content of 6.7 wt%. Coke contents of many zeolites were over 10 wt% (Table 1). From Fig.7, it was showed that the deactivation was mainly attributed to coke product at these reaction conditions, and there was the relation between coke content and B. T. X yield.

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As the catalyst for synthesis of light olefins from methanol, zeolites containing alkaline earth metals (AEZ) were synthesized. The AEZ-W-200 (M'=alkaline earth metal, 200=SiO₂/Al₂0₃ ratio) was synthesized by a hydrothermal method with a gel mixture from (Na₂0, M'O)-(TPA)₂0-Al₂0₃-Si0₂-H₂0 system, where a source of M'O was alkaline earth metal acetate such as Mg, Ca, Sr and Ba. The catalyst activity of methanol conversion into light olefins was studied on the AEZ-M' in compared with the ZSM-5.
The reaction was carried out using an atmospheric pressure fixed bed flow reactor at LHSV=2.3 h_-1 from 400 to 600°C. From these results, the high catalyst activity and t he high yield of ethylene and propylene were demonstrated on AEZ-Mg, Ca and Sr. The maximum yield of ethylene and propylene was 66% on the AEZ-Ca. On the ZSM-5, the deactivation was observed at high temperature. On AEZ-Ba, light olefins were hardly produced.
These zeolites were characterized by determining BET surface area, the particle size by SEM, and the acid property by the methods of NH₃-TPD and FT-IR, and X-ray diffraction (Table 1). Coke contents of these catalysts were measured after the reaction. The AEZM'showed the comparatively smaller coke content. From these physicochemical measurements, it was indicated that on the AEZ-M', not only the amount of strong acid decreased, but also the acid strength became weak. It seemed that the high selectivity to light olefins was demonstrated on the AEZ-M' by the minimization of B. T. X, paraffins and coke products.

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A sensitive method for the spectrophotometric determination of ruthenium(III) with 2-(5bromo-2-pyridylazo)-5-(N-propyl-3-sulfopropylamino)phenol (5-Br-PAPS) is described.5-Br-PAPS reacts with ruthenium(III) to form a 1: 2 (metal: ligand) complex in weakly acidic media upon_ heating at 95°C. The complex has two absorption maxima caused by resonance structure, but the absorbance at 615 nm is largest. The complex gives a constant absorbance in the pH range of 4.4-6.0. The molar absorptivity and sensitivity for an absorbance of 0.001 are 5.90 x 10⁴l./mol^-1cm^-1 and 2 ng. cm^-2, respectively. The complex, once formed, is not decomposed by the addition of EDTA. Thus, the selectivity of the method can be increased by the use of EDTA as a masking agent. The sensitivity of the method can be increased by employing analogue-derivative spectrophotometry, ruthenium(III) determination at parts-per-billion levels being feasible.

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A few electrophilic substitutions of 2, 8-dimethoxydibenzofuran (DMD) and 2, 8-diethyldibenzofuran (DED) have been carried out. The isomer distributions obtained here have been compared with the electrophilic reactivity order estimated by HMO calculations, 3->1->4positions. Reactions of DMD with 99% HNO₃/Ac₂0 or AcOH, with n-BuONO₂/AlCl₃, and with AcCl or PhCOCl in the presence of Aida gave a mixture of the 1- and 3-substituted isomers in agreement with the estimated order, though the isomer ratios depended on the reaction. Nitrations and benzoylation of DED also gave a mixture, of the 1- and 3-isomers. In contrast, acetylation, propionylation, and isobutyrylation of DED in dichloromethane solution gave only the 3-substituted products. These acylations in nitrobenzene gave the 4acylated products as the major product along with the 3-isomer. A steric hyndrance of the 9-hydrogen and the ethyl group against to the attack of acylinium ion at the 1-position of DED has been considered.

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While reaction of 2-chloro-4-(2-hydroxyethylamino)-6-(p-toluidino)-1, 3, 5-triazine [ 5 ] with p-toluidine gave normal aromatic nucleophilic substitution product 2-(2-hydroxyethylamino)4, 6-di(p-toluidino)-1, 3, 5-triazine [ 8 ], 2-arylamino-4-chloro-6-(2-chloroethylamino)-1, 3, 5triazines, [ 3 ] and [ 4 ], with arylamines at 110°C gave 2, 4-diamino-6, 7-dihydroimidazo [1, 2-a] [1, 3, 5] triazine derivatives, [ 6 ] and [ 7 ] respectively, in good yields.
These novel bicyclic heterocyclic compounds are probably formed through aromatic nucleophilic substitution followed by intramolecular cyclization. IR, ¹H-NMR and ¹³C-NMR spectral data of [ 6 ] and [ 7 ] are discussed.

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Naphthothiopyrans such as 2, 3-dihydro-1 H-naphtho[2, 1-b]thiopyran-1-ol [2a], 3 H-naphtho[2, 1-b] thiopyran [3a] and 2, 3-dihydro-1 H-naphtho [2, 1-b] thiopyran [4a] were obtained easily by the protic acid-catalyzed ring-closure reaction of 3-(2-naphthylthio)propionaldehyde [1a] which was formed by 1, 4-addition of 2-naphthalenethiol (2-NT) to acrylaldehyde (AAa). In thes e reactions the ratio of the products can be varied by change of the reaction conditions, and [2a], [3a], and [4a] were synthesized as the main product, respectively. On the other hand, in the presence of nucleophiles (thiols, thiocarboxyl ic acids, acetonitrile), the ring-closure reaction of [1a] proceeded via the addition of nucleophiles to the formyl group to give the corresponding 1-substituted 2, 3-dihydro-1 H-naphtho[2, 1-b]thiopyrans. Similar results were also obtained for 3-(2-naphthylthio)butyraldehyde [1b] and 2-methyl-3-(2-naphthylthio)propionaldehyde [1c].

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It was found that, N-silylamines selectively added to N-cyanoamino compounds affording the corresponding guanidine derivatives at moderate temperature. N-(Trimethylsilyl)diethylamine [3b] reacted rapidly and exothermically with (ethoxyearbonypcyanamide (ECC), Ncyanoutea [8] and cyanamide [10a]. [3b] also reacted at room temperature with N-phenylN'-cyano-S-methylisothiourea [4a], N-butyl-N'-cyano-S-methylisothiourea [4b], N-cyanoguanidine [6a] and N-butyl-N'-phenyl-N"-cyanoguanidine [6b]. N-(Trimethylsilyl)isopropylamine [3a] reacted quantitatively with [4a] at 60°C, whereas the yield of guanidine derivatives obtained by the reactioti with [4b] was only 9% under the same conditions. NCFrimethylsilypaniline [3c] was less reactive and the reaction product with [(methylthio)carbonyl]cyanamide (MCC) or with ECC was salt of MCC or ECC with the corresponding guanidine derivative.

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The conditions, of the reaction of N-silylamines with N-cyanoamino compounds were investigated in detail. Solvents containing no oxygen or nitrogen atoms were found to be preferable. For example, the reaction of N-butyl-N'-cyano-S-methylisothiourea [2a] with N-(trimethylsilyl)diethylamine [1a] afforded 73-75% of the corresponctrig guanidine derivative [3a] in dichloromethane, whereas only 42-49% in dioxane, acetone or acetonitrile under the same conditions.
In the presence of amine salts, especially pyridine nitrate, the reaction was remarkably accelerated. Thus the reaction of [2a] with N-(trimethylsilyl)isopropylamine [1b], N-phenyl-N'-cyano-S-xnethylisothiourea [2b] with N-(trimethylsily)aniline [1c], N, N-dimethylN'-cyano-S-metliylisothiourea [2c] with [1b] and dimethyl cyanoimidodithiocarbonate [4] with [1a] proceeded successfully in the presence of equimolar amounts of pyridine nitrate.

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Thermolysis of dibenzyl ether in tetralin and 1-methylnaphthalene as typical hydrogendonating and -nondonating solvents \was studied at temperature of 380 to 400°C, pressure of 10 to 80 MPa and reaction time of 5 to 40 min by continuous flow reactor. The major products from dibenzyl ether at low initial concentrations was identified as toluene and benzaldehyde with small amounts of benzene and carbon monoxide in both solvents. The product distribution was listed in Table 1. The disappearance of dibenzyl ether obeyed good first order kinetic expression regardless of the changes of solvent used as shown in Figs.2 and 3. The decomposition of dibenzyl ether increased considerably with increasing pressure. Assuming that dibenzyl ether would thermally decompose to afford toluene and benzaldehyde by first-order reaction and benzaldehyde as intermediate decomposes successively to toluene and benzene within our reaction conditions, the rate constant for each of the reaction pathways was estimated by nonlinear regression. These results were summarized in Table 3. Effect of pressure on each step of the reaction was shown in the van't Hoff plot given in Figs.5and 6. The activation volume of dibenzyl ether thermolysis was determined to be 20-30 cm³/mol, such a large negative value suggested fairly polar transition state of the reaction. It may be concluded, therefore, that dibenzyl ether thermolysis under coal liquefaction conditions mainly proceeds by intramolecular hydride-transfer mechanism.

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The chemical structure of coal-derived distillate was studied by high-performance liquid chromatography (HPLC), mass spectrometry (MS) and electronic data processing.
The distillates were accurately characterized by "the diagram of com pound type distribution"obtained by these analyses. The diagram of compound type distribution on hydrocarbons of each distillate indicated the structural distribution of the numbers of aromatic rings (R_a), naphthenic rings (R_n) and carbons of alkyl groups attached to these rings (C_al)as based on the separation behaviour in HPLC and type analyses according to Z number by MS (Figs.5, 6, 7).
The polar co mpounds were characterized by a wide distribution of, polar compound types, though more detailed analyses, using high resolution mass spectra and IR spectrometry, were necessary to determine the chemical structure of polar compound types (Figs.8, 9, 10).
Data processing by electronic computer was irreplaceable in obtaining the above results.

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2-Amino-4-anilino-6-(2-anilino-1-methylethyl)-1, 3, 5-triazine [2] was prepared by the addition reaction of 2-amino-4-anilino-6-isopropenyl-1, 3, 5-triazine with aniline. The above reaction was applied to the synthesis of a new type polyguanamine [3]. The polyguanamine [3] was prepared by the self-polyaddition of 2-amino-4-(m-aminoanilino)-6-isopro penyl-1, 3, 5-triazine [1]. Decomposition temperature of [3] determined by means of TG-DTA method was 330°C.

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2-Acetylamino-4-isopropenyl-6-(N-methylanilino)-1, 3, 5-triazine (AcIMT) was prepared from the reaction of 2-amino-4-isopropenyl-6-(N-methylanilino)-1, 3, 5-triazine (AIMT) with acetic anhydride. The heat of polymerization(δH)for AcIMT was -12.9 kcal/mol derived from the solution polymerization carried out in dimethyl sulfoxide using azobisisobutyronitrile as an initiator. The δH_D for AcIMT was also obtained to be -12.5 kcal/mol using the method of the differential scanning calorimetry. The δH_p for AIMT reported was -12.0 kcal/mol. It was found that thezlHpwas increased by the acetylation of AIMT. The monomer reactivity ratios for the copolymerizations of AcIMT (M₂) with styrene and methyl methacrylate (M₁) at 60°C obtained by considering that the equilibrium monomer concentration of AcIMT was 0.035 moli/ at 60°C were r₁=0.08 and r₂=4.9 for styrene and r₁=0.18 and r₂=6.3 for methyl methacrylate.

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The effect of hydrogenation severity on transformation of mesophase pitches to the optically isotropic texture and the formation, of anisotropic textures from the hydrogenated pitches were examined to characterize the mesophase pitches, prepared by the sedimentation of Ashland A-240 pitch, FCC decant oil pitch and benzene solubles of coal tar pitch. The extent of hydrogenation was controlled by changing the amount of Li metal added to the.mesophase pitch on Benkeser reaction. Anisotropic textures contained in the mesophase pitch were completely converted to isotropic ones for less hydrogenated samples. When the pitch thus hydrogenated was heat-treated over the-temperature range from 573 to 673 K, fineor coarse-grained mozaics formed by the heating at 623 K for 1h and enlarged flow domains at 673 K for 1h, in contrast with the rnesophase pitch hydrogenated to higher degree, in which the treatment at 673 K for 1h brought about only very fine spheres. Such behavior of the mesophase pitches prepared here suggests that the orientation of the lamellae constituting the mesophase is very labile to the hydrogenation because of weak interaction betWeen the lapellae in the mesophase. In addition, the influence of the hydrogenation on the appearance and the growth of anisotropic textures is discussed in connection, with the structural changes of the constituent molecules.

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Hydrogenation and heat-treatment of mesophase pitch were carried out and the effect of additives was investigated to obtain single mesophase spheres with high concentration. The mesophase pitch prepared from coal tar pitch by sedimentation contains about 30% of toluene solubles and 64% of quinoline insolubles (QI) which are easily converted to quinoline solubles by hydrogenation using the Benkeser reaction. When the mesophase pitch hydrogenated was heat-treated in a sealed tube from 623 to 648 K and then cooled slowly at the rate of 1 K/min, optical anisotropic textures consisting of aggregated and coalesced spheres were observed in the product with a considerable amount of QI. The QI content of the product increased with the heat-treatment temperature, whereas the amounts of toluene and pyridine insolubles were almost the same in these temperature ranges as those of the hydrogenated mesophase pitch without the heat-treatment. On the other hand, the elemental analysis of the heat-treated pitches indicates that H/C atomic ratio gradually decreases with an increase in the heat-treatment temperature. From these results the formation of QI and anisotropic textures is considered to take place through physical changes accompanying molecular orientation as well as chemical reactions. The anisotropic textures with most of the condensed single spheres appeared when, p-terphenyl or 2, 2'-binaphthyl was added to the hydrogenated mesophase pitch and heat-treated under the same conditions. Such a Phenomenon suggests that these additives prevent the coalescence of the spheres because of the adhesion to the surface of the spheres. The fluidity of the pitch is maintained even St a lower temperature by the addition of these chemicals. Consequently, the formation of the spheres is considered to occur at such a low temperature. This effect might also be the another factor for the aggregation of the spheres.

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Polyelectrolyte complexes (PECs) consisting of [2-(diethylamino)ethyl]dextran hydrochloride, glycol chitosan, and the sulfate of poly(vinyl alcohol) have been prepared. The cornposition of the PEC was found to depend appreciably on the experimental conditions.
The PEC membrane prepared in a 2.27 mol.dm^-3 HCl solution was m ost resistant to alkaline and acidic environments. The transport behavior of alkali metal ions through this membrane was much affected by the hydrogen ion concentration providing the driving force, and especially by organic solvents. It is suggested that a change in the chemical and physical properties of the PEC membrane caused by a hydrogen ion concentration change, controls the active and selective transport through the membrane.

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The absorption spectrometry showed that a direct dye type fluorescent brightening agent (FBA [1] ) flocculated in aqueous solution at higher concentrations, at lower temperatures, a nd at lower pH. The dye in flocculation had a new absorption band in the visible region (λ_max 420 nm), and was harder to fade as compared with that in molecular solution. The photofading process of the dye molecularly dissolved was a reversible trans-cis isomerization, reaching a cis-rich photostationary state by UV irradiation. The fraction of the cis-isomer was higher at higher concentrations.

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A continuous and automatically-controlled wastewater treatment system is described for simultaneous removal of hazardous metals. The process consists of treatment of wastewater at pH 10 with sodium hypochlorite and subsequent treatment with excess amount of iron(II)sulfate. The hypochlorite concentration was kept at 1.0 mmol.dm^-3 in the treatment tank using a hypochlorite probe. The concentration of the iron(II) was maintained at 5.5 mg.dm^-3 of dissolved oxygen (DO) using a DO meter as the detector. In the subsequent s tep, 1.75 times as much iron(II) as that added in the preceding step was added. Thus ha zardous metals were coprecipitated with the resulting hydrous iron(III) and iron(II) oxides. As (V), Cd(II), Cr(VI), Cu(II), Mn(VII), Pb(II), and Zn(II) were simultaneously removed even in the presence of ammonia, citrate, cyanide, ethylenediamine, oxalate, tartrate, and thiocyanate. These metals were not leached out of resulting sludges on leaching tests. The system was also applied to seawaters with satisfactory results.

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The capacitance and resistance of the titanium(IV) oxide film prepared by anodic oxidation accompanied by sparking in Na₂CO₃ solution were measured as a function of relative humidity (RH). The capacitance and resistance in a parallel equivalent circuit increased with the increase of relative humidity, while the resistance decreased. The response was very sensitive in the humidity region less than 50% RH. The surface of the titanium(IV) oxide film was presumed to be doped with Na₂CO₃ from the infrared spectrum. The mechanism of the humidity response of the capacitance and resistance are discussed from the current measurement under the pulsed voltage.

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The novel Rhodamine B dyes having one or two long alkyl chains were synthesized. Monolayers of these dyes have been prepared at the air-water interface by spreading the mixture of dye molecules and matrix molecules. Absorption spectra of the dye films which were transferred from the water surface to the quartz plate by the Langmuir-Blodgett technique have been measured.
They were comp ared with the dye layers which were prepared by adsorption of Rhodamine B molecules without having long alkyl chains from the subphase to the matrix monolayers.

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Separation among g allium(III), indium(III)and aluminium(III) by the extraction with trioctylamine(TOA) from an aqueous oxthlates solution containing chloride ions or sulfate ions has been studied. Indium(III)is separated into an organic phase from alurninium(III) in an aqueous oxalate solution and from gallium(III)by the addition of sodium chloride to an aqueous oxalate solution with TOA-xylene extraction. For the separation of gallium(III) from gallium(III)-aluminium(III), the addition of sulfate to an aqueous oxalate solution has been found to be more effeptive. However, aluminium(III) can not be extracted selectively into the organic phase leaving gallium(III) or indium(III)in the aqueous phase. Moreover, the dependence of the separation factor on TOA concentration has been investigated. It was observed that the suitable TOA concentration for these investigated system depends on the distribution ratio of more extractable metal species.

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The reaction of acridine hydrochloride with aniline in the presence of lead(IV) oxide, peroxides of alkaline earth metals, metal chloride or mercury(II) sulfate as an oxidizing agent was examined. It was disclosed that metal chlorides (such as silver chloride and mercury(II)chloride) were effective to give 9-(4-aminophenyl)acridine in high yields.

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The polymerization of methyl methacrylate (MMA) or acrylamide using glutathione (reduced form. GSH) as an, initiator was carried out. It was found that GSH showed initiating activity of radical polymerization in the presence of formic acid. Detailed study for the polymerization of MMA gave the following results. The overall activation energy for the polymerization was estimated to be 54.8 kJ.mol^-1. The rate of polymerization (Rp) was shown by the following equation.
R_p = k [MMA]^1.05 [GSH]^0.53
The chain-transfer consta nt to GSH was approximately evaluated as 3.0x10^-2 at 60°C.

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