Series of trans- and cis-diorganopalladium(II) complexes, trans- and cis-PdRR'L₂ (R, R'=alkyl and/or aryl groups L=tertiary phosphine ligands) have been prepared, and their reductive elimination reactions and reactions with organic iodides examined in detail. The following features emerge from the studies. (a) For reductive elimination to take place the two organic groups must be situated in mutually cis positions. (b) trans-Diorganopal-ladium complexes isomerize to their cis isomers prior to reductive elimination. (c) Ease of reductive elimination varies depending on the ligands and organic groups. (d) Aryl groups reductively eliminate more easily than alkyl groups. (e) In the presence of organic iodides trans-diorganopalladium complexes are isomerized to their cis isomers, the process being catalyzed by monoorganopalladium species generated in the systems. (f) cis-Dime-thylpalladium(II) probably forms a Pd(IV) species on interaction with organic iodides and reductive elimination proceeds from the organopalladium(IV) intermediate. On the other hand, cis-PdMe(Ar)L₂ complexes afford MeAr without participation of organic iodides.

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The electrolytic conductivities of several tetrabutylammonium nitrophenolates in pyridine were measured at 25°C, and the dissociation of tetrabutylammonium salts and the behavior of tetrabutylammonium ion (Bu₄N⁺) were examined. The conductance behavior (Fig.1)of all the salts examined was Interpreted as the dissociation of simple ion pairs, similar to that of the strong electrolytes. The conductometric data were analyzed by the FuossKraus method, and the dissociation constants of the tetrabutylammonium salts were calculated. The limiting molar conductivity of Bu₄N⁺ was determined to be 21.87 S.cm².mol^-1 on the basis of the limiting molar conductivity of tetrabutylammonium tetraphenylborate (Table 1). By taking account of the electrophoretic and relaxation effects of the oppositely charged ions, a new method for calculating the electrolytic conductivity of ions was proposed. Through this method, a new relationship was found between the electrolytic conductivity of Bu₄N⁺ and the ionic concentration. The ionic electrolytic conductivity of Bu₄N⁺ was dependent only upon the ionic concentration of Bu₄N⁺ regardless of the kind of counter ions (Fig.3). It was o bserved that the radius of the solvated Bu₄N⁺ in pyridine obtained by using eq. (8)became larger with the increase in the ionic concentration (Fig.5). The Stokes radius of Bu₄N⁺ in pyridine was almost the same as that in water. The difference between the degree of dissociation of the tetrabutylammonium salts in water and that in pyridine is attributable to the difference in the size of the region in which ion pairs are formed, rather than the size of solvated ions.

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Zeolites containing alkaline earth metals (AEZ-M'-X, M'=Alkaline earth metals, X=Si0₂/Al₂0₃ ratio) were known to be effective catalyst for the production of light olef ins from methanol. The catalytic performance of these AEZ-M' zeolites in methanol conversion to light olefins was studied by varing the kind of alkaline earth metals and the SiO₂/Al₂O₃ratio of the zeolites. The reaction was carried out under an atmospheric pressure with a fixed bed flow reactor at LHSV=2.3 h^-1 and temperature ranging from 400 to 600°C. As shown in Fig.1, the value of the optimum Si0₂/Al₂0₃ ratio of AEZ-M' to give the maximum yield of ethylene and propylene at each reaction temperature was dependent on the kind of alkaline earth metals. The yield of light olefins increased with the reaction temperature. Among AEZ-M', AEZ-Ca with Si0₂/Al₂0₃ ratio of 100-300 were the most effective catalysts for the production of light olefins from methanol, and gave the maximum yield of (ethylene and propylene) of 65% at 600°C (Fig.2). However, the yields of B. T. X and paraffins at 600°C and the amount of coke were very low. Further, it was found that the deactivation of the catalyst at high temperature was attributed to the poisoning of the active sites by coke deposition. The characteristics of zeo lites were done by BET surface area and the particle size by SEM (Table 1, Fig.3). Further, AEZ-Ca, which was the most effective catalyst for the production of light olefins from methanol, was characterized by FT-IR (Figs.4, 5)and ²⁷Al-MAS NMR (Fig.6). It was found that most of the strong acid sites were changed to the weak acid sites by the modification with Ca, and that Ca occluded was present in the neighbourhood of Al.

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Catalytic reduction of nitrogen monoxide with ammonia over a PAN-ACF, an active carbon and their derivaties further activated with sulfuric acid was studied at 150°C using a fixed catalyst-bed in a flow reactor. It was found that the catalytic conversion was influenced by nitrogen monoxide and oxygen concentrations in the reactant gas. The catalytic activities of these carbons were very much enhanced by the activation with sulfuric acid, PAN-ACF exhibiting the highest activity to convert ca.60% of nitrogen monoxide at W/F of O.02 (g.min/ml) for 20 h when the reactant gas contained 1% nitrogen monoxide without oxygen. Although the low concentration of nitrogen monoxide (400 ppm) decreased very much the stationary conversion over all carbons at the same W/F, addition of oxygen into the reactant gas (4%) increased very much the conversion and maintained the conversion level for longer than 20 h. Thus, PAN-ACF-B activated with sulfuric acid exhibited a conversion of ca.73% at W/F of 0.005 (g.min/ml). The kinetics, the reactivities of carbons against NO and TPDE of carbons (to produce CO and CO₂) suggest, that the active sites for this reaction are a portion of surface oxygen functionalities and that they are produced and regenerated during the catalytic reaction through the oxidation with NO or oxygen of relatively high concentrations (a few %) in the reactant gas.

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CO2 of atmospheric pressure containing saturated water Vapor reacted with ZnO fine particles at temperatures of 5, 10 and 20°C to form the following three kinds of basic zinc carbonates (zinc carbonate hydroxides): (1) at 20°C, the basic carbonate, whic h has the same composition ratio of metal, H₂0 and CO₂ and the same X-ray diffraction pattern as rosasite (Cu, Zn) CO₃(OH)₂ (JCPDS 35-402), and the metal which consists of only Zn. (2) at 10°C, hydrozincite Zn₅(CO₃)₂(OH)₆ (JCPDS 19-1458). and (3) at 5°C, the basic zinc carbonate, which has a X-ray d iffraction pattern not ever reported and not listed in JCPDS and the composition ratio of 1:2 between CO₂ and H₂0. All the above three kinds of basic zinc carbonates, when they were reacted fu rther under the respective conditions described above, finally changed to the neutral zinc carbonate ZnCO₃, smithsonite (JCPDS 8-449). The thermal analyses of these four kinds of reaction products were carried out by DTA and TGA. The measurements of CO₂-releasing properties upon heating, and their quantitative analyses were also carried out by FID gas chromatography. As the analyses have revealed that there exists a liqud phase between the solid and the gas phases in the reaction steps, the mechanism of the reaction was examined. This reaction, with its conditions precisely controlled, will be effective for adding new functions or reforming the surface of ZnO particles.

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The study of the anion adsorption on various hydrous metal oxides in the aqueous phase showed that the adsorption of fluoride ion on the hydrous rare earth oxides was excellent. The results were due to the relatively small ionic potential and strong basisity of rare earth ions. Therefore, they had strong tendency to dissociate OH group into hydroxy ion (Table 1, Fig.1). The adsorption on hydrous ceric oxide, which was prepared by drying at 50°C or -80°C under vacuum and consisted of microcrystallines having disordered structure (Fig.3), was studied in detail. The specific surface area of hydrous ceric oxide decreased with the elevation of drying temperature, due to the crystallization of microcrystallines (Table 2). The adsorbability decreased with the decrease of specific surface areas (Fig.5). As for monovalent ions, the adsorption decreased in the following order: F^->Cl^->NO₃^->BF₄^->Br^->Cl0₄^- (Table 3). It was suggested that the large ions suffe red from a strong steric effect because of the limited available space of the ion-exchange site. Hydrous ceric oxide was found to have the adsorbability towards F^-, HPO₄^2-, As(III) and B(OH)₄^- (Fig.7). The adsorption selectivity of coexisting anions was in the following order: F^->HPO₄^2->SO₄^2->Cl^-, Br^-, NO₃^- (Table 4). The extremly high selectivity for F^- was a ttributable to the smaller ion radious of F^- compared to that of OH^-. An infrared absorption peak (1500 cm^-1), which is attributable to the OH groups of hydrous ceric oxide, disappeared by the adsorption of anions (Fig.8). The ion exchange between the OH groups of hydrous ceric oxide and anions was confirmed to be reversible.

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Three composites CF-Al, CF(Ni)A1 and CF(Cu)Al of carbon fiber/aluminium were prepared by the hot pressing techniques at temperatures of 500°C (P-method) and 670°C (M-method), and at a constant pressure of 200kg/cm2 (2.03×10⁷ Pa). Carbon fiber was co ated by Ni or Cu metals in order to have a good joining with the aluminium matrix. The maximum tensile strength of CF(Cu)A1 composite was abo u t three times as large as that of (Cu)Al metal composite. Although two hot pressing techniques of P- and M-methods were used, the former was superior to the latter because it gives the composi te with better joining characteristics between carbon fiber and metal matrix (plus a coating agent) and less solibility of metals into carbon fiber. EPMA study of CF(Cu)Al composite revealed that about 50-60% Al diffused to Cu and that Cu diffused only 5% to Al and slightly diffused to carbon fiber. On the other han d, in a case of CF(Ni)Al composite, 2-10% of Ni diffused to Al, but about 30% o f Al diffused to Ni. It was fou n d that the tensile strengths of the three composites studied were in agreement with those obtained by the use of Telelman's fracture toughness mechanism.

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An investigation was made on the photochemical reaction of Co^II(dmgBF₂)₂ (the BF₂ capped species of bis(dimethylglyoxpato)cobalt(II)complex (Co^II(dmgH)₂), Fig.1) in methanot solution containing an excess amount (with the molar ratio of about 2-6: 1) of tributylphosphine (P(n-C₄H₉)₃). The color of the methanol solution, which was purple at temperature higher than -20°C and blue at temperature lower than -40°C, was changed from purple to blue by the irradiation with a low-pressure Hg lamp at room temperature. The visible absorption spectrum of the blue solution was quite similar to that of the blue solution at the temperature lower than -40°C. Therefore, the photoproduct and the low-temperature species of the methanol solution were identified as the same species. The absorption spectrum of the blue solution was also similar to that of Na⁺[Co^I(dmgH)₂.P(n-C₄H₉₃)]^-. Thus, the photoproduct was assigned to H⁺[Co^I(dmkBF₂)₂.P(n-C₄H₉)₃]^-. The photochemical color-change reaction was not observed in benzen or dichloromethane solvent. Therefore, it was proposed that the present photochemical reaction was interpreted by the mechanism in which the central divalent cobalt ion was reduced to the monovalent cobalt ion by methanol.

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Flotation of citric, malonic and oxalic acids by complexing with iron(III) and its application to the determination of the acids were investigated. A 20 ml of 2.0×10^-4 mol.dm^-3 organic acids and iron(III) was adjusted to the desired pH and was subjected to flotation using 6.0×10^-4 mol.dm^-3 dodecylaminium acetate (DAA) as a surfactant and nitrogen bubbles in a cell (20 cm×2.7 cm I. D.) for 10-20 min. Recoveries of the acids were 97-99% at pH 5-6. The composition of the scum determined by the mole ratio met hod was consistent with the analytical results for nitrogen and ironan. From the composition of the scum, it seems that the flotation of citric acid proceeds through the formation of the ion-pair complexes of RnFeL(OH)n, s, where R and L denote the cation of DAA and the anion of citrate, respectively. One liter of waste water in an orange juice factory was subjected to flotation in a cell (40 cm×6.6 cm I. D.). After iron(III) in the scum was removed by using a cation-exchange resin column (5 cm×0.9 cm I. D.), citric and oxalic acids in the effluent were determined by ion chromatography. From the results, it was found that this method was applicable to the determination of 0.1-1.5 ppm citric and oxalic acids in a waste water.

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In order to obtain information on the dyeing mechanism of polyester fibers with disperse dyes, interactions between poly(ethylene terephthalate) film (PET) and disperse azo dyes have been investigated by the analysis of visible absorption spectra in terms of a modified McRae's equation. From the results, a more real estimation of the interactions was obtained. The following disperse azo dyes were used: The wavenumber shifts of the absorption maxima of the dyes in dyeing PET were measured. A linear relationship was obtained between the calculated and observed frequency shifts. The dipole-dipole force of the azo dyes estimated from the equation was 0.2-O.5kcal/mol and/or 2-3% of the total dye-PET interaction. The sum of the dispersion and induction force of the azo, dyes estimated from the equation was 9-15 kcal/mol and/or 97-98% of the total dye-PET interaction. It appears that the dispersion force ma kes a considerable part of contribution to the dye-PET interaction, and dipole-dipole force and induction force make a much smaller contribution to the interaction.

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Interesting substrates, N-carboxy α-dehydroamino acid anhydrides (ΔNCA) were easily prepared by cyclization of N-(benzyloxycarbonyl (Cbz) α-dehydroamino acids (Cbz-DHA)with thionyl chloride. In addition, it was found that hydrolysis of N-carboxy N-(tbutoxycarbonyl(Boc))- α-dehydroamino acid anhydrides (Boc-ΔNCA), derived from ΔNCA and (Bu'OCO)₂O as unstable intermediates, took place to give Boc-DHA in good yields, for the first time. Subsequently, a few direct and indirect esterifications of Boc- and Cbz-DHAs with alcohol by the usual methods- were tried successfully. Especially, the reaction of Cbz-DHA with t-butyl acetate or isobutene in t-butyl alcohol in the presence of concentrated sulfuric acid proceeded to give previously unknown Cbz-DHA t-butyl esters in good yields. On the other hand, facile alcoholysis of Boc-ΔNCA with an appropriate alcohol except t-butyl alCohol was performed to give the expected Boc-DHA esters. Consequently, esterification, by using t-butyl acetate and by the ΔNCA method were found to be very effective for obtaining DHA esters having the useful N-protecting groups.

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The thermal ring opening reactions of 1-(polyfluoroalkyl)-4-aza-1-azoniabicyclo[2.2.2]octane o-nitrobenzenesulfonates [1a, b-I] and chlorides [1a, b-II] were investigated under various conditions. [1-II] reacted much more easily than [1-I]. the former afforded ring opening products 1-(polyfluoroalkyl)-4-(2-chloroethyl)piperazines [2-II] at 110°C for 20 minin nitrobenzene, and ring-opening dimers 3, 12-bis(polyfluoroalkyl)-3, 12-diaza-6, 9-diazoniadispiro [5.2.5.2]hexadecane dichlorides [3-III] at 160°C for 1h in the same solvent, in high yields (78-430 and 80-81% respectively), while the latter were stable at 110C, but gave the corresponding ring-openihg dimers [3-I] in good yields (52-65%) at 180°C. In water (100°C, 20 h), no ring opening took place fur [1-I] and [1-II].

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In the series of the investigation on reactivities of azoxybenzenes, this report deals with isomeric conversion in the reaction of three sets of para-substituted azoxybenzenes with sulfuric acid. Under the conditions of the Wallach rearrangement, 4-(phenyl-ONN-azoxy)- [1α] and 4-(phenyl-NNO-azoxy)benzoic acid [1β] underwent α, β-interconversion in both monoand diprotonated states. Methyl 4-(phenyl-NNO-azoxy)benzoate [2β] was also converted into methyl 4-(phenyl-ONN-azoxy)benzoate [2α] under the Wallach rearrangement conditions, while [2α] did not undergo α, β-conversion under the same conditions. In the reaction of a mixture 4-(phenyl-ONN-azoxy)phenyl [3α] and 4-(phenyl-NNO-azoxy)phenyl acetate [3β](α/β=0.63) with sulfuric acid, 4-hydroxyazobenzene [7] was obtained as a major product with a small amount of 4-(phenylazo)phenyl acetate [10], and β, α-aconversion was observed during the reaction.

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In the equimolar reaction of benzhydrol and its derivatives with iron(III) chloride (FeCl₃)in nitromethane, chlorination took place to yield chlorodiphenylmethanes with corresponding benzophenones as a by-products. The use of FeCl₃ with small amounts of tribenzylamine can bring about the increasing yield without the formation of benzophenones. Similarly, the yield of chlorodiphenylmethanes increased with elavated molar ratio (benzhydrols/FeCl₃=1.5).

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Oxidative decompositions of phenol and ethylene gylcol by ozone were studied in aqueous solution. Formic acid, glyoxal, glyoxylic acid, oxalic acid, muconic acid and maleic acid were detected as principal reaction products in the oxidation of phenol. The decrease of TOC was recognized, which was assumed to be caused by both the anomalous ozonolysis of α, β-unsaturated carbonyl compounds and the decomposition of formic acid formed. On the other hand, glycolaldehyde, glyoxal, glyoxylic acid and oxalic acid were detected as reaction products in the oxidation of ethylene glycol. In this case, the decrease of TOC wasn't recognized. The decomposition reactions of phenol and ethylene glycol were both expressed as follows. Where So and S are substrate's concentrations at t=0 and t, respectively, and D is an ozone dosage rate. The apparent rate constant and the apparent activation energy for the phenol oxidation were 4.2-5.7×10^-1 mol of phenol. mol ozone^-1 and 12.4 kJ/mol respectively, and those for the ethylene glycol oxidation were 5.6-10.3×10^-2 mol of ethylene glycol. mol ozone^-1 and 47.4 kJ/mol respectively. In the TOC removal for phenol oxidation, plots of the residual rate of TOC versus the ozone dosage per mol phenol presented two linear portions, the position of the break changing with temperature. From the fact that catechol, hydroquinone, muconic acid, maleic acid and fumaric acid showed the same break while formic acid didn't, it was assumed that the break corresponded to the transition state from a system composed of unsaturated compounds to one composed of aliphatic compounds.

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The kinetics and mechanism of the pyrolysis of thietane have been studied below 1100 K at 10^-2 Pa by using the very low pressure pyrolysis technique (Table 1). Thietane decomposed above 900 K (Fig.1) to yield ethylene and th ioformaldehyde. The amount of ethylene produced was nearly equal to that of thietane reacted (Table 2), meaning the stoichiometry of this reaction as follows. Assuming that biradical mechanism is valid in this system, unimolecular reaction rate constant k_unl (Table 3, Fig.2) obtained is considered to be separated to the following three cases. Combining the estimated entropy change of each case (Table 4), high pressure Arrhenius parameters were given as follows (Table 5), by means of RRKM unimolecular theory (Table 6). These activation energy values are closed to those, which are estimated on the assumption that thietane decomposes via biradical. From these values, the activation energy for decomposition and the ring closure of biradical C-C-C-S are estimated to be the same, about 10-20kJ.mol^-1. It is concluded that thietane decomposes via biradical mechanism in both thermolysis and photolysis, as is in contrast to the case of cyclobutane.

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Carbon fibers and 4% solution of pentacarbonyliron in Ph₂CH₂ were heated at 177°C for 10 hours to form carbon fibers coated with Fe metal. The decomposition of Fe(C0)5was accelerated by addition of catalysts such as Pd metal. The catalysts and/or the pretreatment of carbon fibers changed the crystal state of Fe metal deposited on the surface of fibers. In order to deposit Fe metal on the sufface, carbon fibers were treated with H₂SO₄-K₂Cr₂0₇, sensitized by SnCl₂ and subsequently activated by PdCl₂. The coating state of Fe-coated carbon fibers was investigated by scanning electron microscope (SEM) and electron probe microanalyzer (EPMA). Pretreated carbon fibers were uniformly coated (Fig.5). In contrast to this, the carbon fibers without pretreatment oould not be coated well as shown in Fig.4. The 61% of Fe metal obtained from Fe(C0)₅ was deposited on the surface of fibers with pretreatment, whereas only 34% of Fe metal was deposited on the surface of carbon fibers without pretreatment. Pd metal and/or the pretreatment of fibers accelerate and complete the decomposition reaction of Fe(C0)₅. The speed of decomposition increased with an increase of the ratio of Pd/Fe(CO)₅. The crystal state of the Fe metal on Fe-coated carbon fibers was investigated by X-ray diffraction (Fig.6). When Pd metal is added and fibers are pretreated, the spectrum shows sharp peaks assigned to Fe crystals. In the case of Fe₂(CO)₉, only 14% of Fe metal was deposited on the surface of pretreated fibers because of its low solubility in Ph2CH2.

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The decomposition of limonene 1, 2-oxide [1], 2-pinene oxide [2] and 2(10)-pinense oxide [3] with formic acid in the presence of synthetic zeolites (3A, 4A, 13X and TSZ-645-PSH1 zeolite) was investigated. The results obtained are as follows: With formic acid in each synthetic zeolites, the decomposition of [1] gave dihydrocarvone [4] with high selectivity (87% at optimum). The decomposition of [2] with formic acid in the presence of 13 X zeolite afforded predominantly α-campholenaldehyde [9]. Perillyl alcohol [12] was obtained from [3] with 84% selectivity by the reaction with formic acid in the presence of 13X zeolite. Their structures were determined by IR, ¹H-NMR and MS spectra.

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Three sequential glutamic acid polypeptides, ply(X-Glu) (X: Ala, Leu, Phe), were synthesized by the diphenylphosphorazidate method. The conformations of these polypeptides were studied by means of circular dichroism (CD) spectroscopy in water. The conformations depended on the amino acid sequence and the ionization state of the side chain. When pH was changed, the conformational transition was from a helix (partial) to a random coil in poly(Ala-Glu) and poly(Leu-Glu), while a, β-structure participated in the transition of poly(Phe-Glu). Chiral interaction between Lpoly(X-Glu) and a dye (Acridine Orange) was first examined from the absorption and induced CD spectra. On complexation with the dye, the sequential polypeptides exhibited induced CD at the visible wavelengths corresponding to the blue-shifted absorption bands in a wide pH range of 4.5-9.2. The shape and magnitude of the induced CD were affected by the bulkiness and/or hydrophobicity of the side chains in poly(X-Glu). The increased bulkiness exhibited the larger ellipticity in induced CD of the complex.

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In the propagation reaction in radical polymerization, the difference, Δ_X, between Mulliken's electronegativity of monomer(M) and that of radical(R) is expressed by Eq. (5), according to Koopmans' principle. Eigenvalues(E) of HOMO, LUMO and SOMO were calculated by ab initio restricted Hartree-Fock MO method, as shown in Table 1. Since the value of -2Δ_X was positive, as Ishown in Table 1, a formation of following charge-transfer complex, [2], was suggested to be probable. However, it was theoretically denied that the application of Koopmans' principle could give any right result. In fact, the correlation of -2Δ_X with the observed Ep≠ gave no reasonable conclusion (Fig.3 in Text). We proposed a new parameter of Δ_X' which is expressed by Eq. (9) and Fig.4. Δ_X' has following meanings. When HOMO of monomer perturbs with SOMO of radical, electron flows from monomer to radical. Inversely, in the perturbation of SOMO with LUMO of monom er, the electron transfer proceeds from radical to monomer. The largeness of electron transfer can be considered to be in proportion to the perturbation energy (ΔE), that is the, larger the ΔE, the easier the electron transfer. As can be understood by Eq. (8) in Text, when the width between the eigenvalues of two perturbing MO is smaller, ΔE be comes larger. Accordingly, Δ_X' is an index of the difference between the electronegati vies of the reacting radical and the monomer. If Δ_X' in eV is positive, the electron flows from monomer to radical. As Table 3 shows, all Δ_X' are positive. This result gives a strong support for the formation of CT-complex of [2]. As shown in Fig.5, Δ_X' correlated linearly with Ep≠. Eq. (12) was deduced. By a comparison of I E_HOMO-E_SOMO with E_SOMO-E_LOMO, it is clear that the former is neglegibly smaller than the latter. Thus, Eq. (13) was obtained. Equation (13) is the same as that obtained experimentally and theoretically in the former paper.

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For commercial-scale production of highly loaded CWM (coal-water mixture), it is necessary to predict its future stability immediately after production. However, the previously reported method of evalua ting the stability is unable to predict it because it takes a long time to obtain results. We have found a quantitative correlation between the yield point and stability of CWM, from the rheological characteristics of CWM, and the following conclusions have been attained.1) The Saxon Vale coal CWM showing a higher yield point was found to remain stable for a longer period.2) With an increase in the agitating energy applied to CWM, its yield point is improved and the stability period is lengthened.3) With an increase in the amount of a dispersant added, the yield point is lowered to a certain stationary value. This suggests that an optimum dispersant amount exists for stabilization of CWM.4) The smaller t he coal particle size is, the higher the yield point is. Likewise, with an increase in the coal concentration, the yield point is raised.5) A more-immature coal having larger (H) and (0) values shows lower yield point, or is poorer in CWM stability.

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It was found that several new types of chiral smectic C phases composed of chiral molecules exhibit CD (circular dichroism) with large CD magnitude. The observed CD band was discussed in terms of its helical sense and helical pitch, which are in good agreement with those observed by other optical measurements. The pitch band CD in its magnitude and in its wavelength depend on the temperature and the sample thickness, being due to change in the pitch of the phase. Especially, helical pitch variation in the liquid crystal composed of p-(hexyloxy)phenyl 4'-[(S )-2-methylbutyl]biphenyl-4-carboxylate was unusual and discontinuous at the transition temperature of cholesteric to smectic and vice versa. The CD technique provides a useful and powerful tool for the analyses on helical sense, helical pitch, and other twisted structures.

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Synthesis and the structure of the carbazole dioxazine pigment were investigated. The carbazole dioxazine with a linear structure, 5, 15-diethyl-8, 18-dichloro-5, 15-dihydrodiindolo[3, 2-b: 3', 2'-m]triphenodioxazine [I], was newly synthesized by demethanolation of 2, 5-bis(9-ethyl-2-methoxy-3-carbazolylamino)-3, 6-dichloro-1, 4-benzoquinone [9] in 1-chloronaphthalene. Compound [I] is green powder showing the absorption maxima at 540 and 584 nm. Qn the other hand, the ring closure of [9] with p-toluenesulfonyl chloride in DMSO afforded 5, 15-diethyl-9, 19-dichloro-7, 17-dimethoxy-5, 15-dihydrodiindolo [3, 2-a: 3', 2'-1]triphenodioxazine [III] having an angular structure. It was concluded that [X] has not a linear structure by comparing the properties of [I] with those of carbazole dioxazine (X) conventionally obtained. Carbazole dioxazine, 5, 15-diethyl-5, 15-dihydrodiindolo[3, 2-b: 3', 2'-m]triphenodioxazine [IV] (linear structure) and 5, 15-diethyl-7, 17-dimethoxy-5, 15-dihydrodiinolo[3, 2-a: 3', 2'-1]triphenodioxazine [V] (angular structure)not containing chlorine atoms were synthesized and the effect of chlorine atom was examined.

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A new Index AQI (Air Quality Index) is proposed for evaluation of air quality. The application to Kanagawa Prefecture is also presented. Pindex, PSI and ORAQI were already proposed in the United States as combined air pollution indexes, but they had some difficulities in application to the situations in Japan, because of differences of air quality, air quality standards and so on. In calculation of AQI, SO₂, NO₂, CO, O_x and suspended particulate were chosen as air pollutants. Sub-AQI was defined as (daily mean concentration/air quality standard)×10 for each pollutant except Ox. Sub-AQI of O_x was taken as daily maximum concentration. The largest sub-AQI was defined as AQI, and the pollutant which gave API was taken as a main pollutant. Pollutants of the sub-AQI of which exceeded 11 were also included in main pollutants. AQIs were divided into 5ranks, clean, moderate, polluted 1, polluted 2 and polluted 3 for simplification of evaluation. The evaluation of AQI for the environmental air in Kanagawa Prefecture agreed well with the actual situation of air quality.

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A simple analytical method is proposed for thermal desorption curves and desorption efficiencies of organic solvent from activated carbon. Basic equations are obtained from mass balance in desorption column, mass transfer of organic solvent vapor from the inside of particles to gas stream, and adsorption isotherm. Two assumptions are made in order to solve these equations analytically.i.e., concentration of solvent vapor is uniform both in the gas and solid phases, and adsorption isotherm is linear. When adsorption isotherm is curved, it is approximated by several straight lines. Comparison of the analytical, process showed that the mass transfer rates of solvent vapors were so rapid, and the shapes of desorption curves were affected mainly by the adsorption isotherm. The estimated desorption curves and desorption efficiencies agreed well with the experimental values for ethyl acetate especially in the case of a large diameter of column. However, the estimated desorption efficiency of toluene was a little lower than the experimental one.

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Effects of underpotential deposition (UPD) on the anodic oxidation of C₁ fuels such as CH3OH or HCOOH were studied by using Pt electrodes of different roughness factors (R.F.). When a small amount of Pb²⁺ was added to the HCOOH solution, an extraordin arily large enhancement was observed on a smooth Pt electrode, while the enhancement became smaller as the R. F. increased. With an electrode of R. F. of 540, anodic currents iincreased bycabGut 20-40% on addition of Pb²⁺ at the constant potential electrolyses.

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The sawdust of Sugi (Cryptomeria japonica D. Don) was extracted with supercritical carbon dioxide (SC-CO₂) at 27.0 MPa and 313 K to obtain the essential oil which corresponded to 19.8% of the hexane extract. GC-MS analysis of the neutral parts of both extracts revealed that SC-CO₂ extract contained moderate amount of sesquiterpenes which we re f ound in the hexane extract as trace components. Furthermore it was found that SC-CO₂ extract did not contain two phenanthrene derivatives which were included in the hexane extract, but contained other two phenanthrene derivatives which were not found in the hexane extract. Microscopical observation of the wood suggested that above mentioned discrepancy was due to a difference of osmotic action between SC-CO₂ and hexane for the contents of the ray parenchyma or longitudinal wood parenchyma.

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Four new peroxy esters, of which three compounds have the carboxy groups in the neighboring positions of the peroxyl group, were synthesized in good yields. t-Butyl 2(carboxy)cyclohexaneperoxycarboxylate and t-butyl cis-6-carboxy-3-cyclohexene-1-peroxycarboxylate were prepared by adding t-butyl hydroperoxide to each corresponding dicarboxylic acid without solvent, t-Butyl o-carboxyperbenzoate and t-butyl o-chloroperbenzoate were prepared by adding t-butyl hydroperoxide to phthalic anhydride and o-chlorobenzoyl chloride, respectively. The polymerimti6n of styrene was carried ogt by using three peroxy esters having the carboxyl groups as the initiators. The polymerization was initiated by the peroxy esters, but it was slow itomparedi with that, initiated by azobisisobutyronitrile under the same conditions.

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