Calixarenes are cavity-shaped, cyclic oligomers synthesized from phenols and formaldehyde. We designed and synthesized a number of new host molecules from calixarenes. Introduction of ionophoric groups into the lower rim of the calixarene cavity brought up calixarenes as cyclic ionophores with crown-like functions. In particular, calix[5]arene and calix[6]arene with carboxylate groups acted as "super-uranophiles" exhibiting the record-breaking uranyl affinity (K=10^18.4-19.2 M^-1) and uranyl selectivity (10^10.6-17). Inclusion of organic guest molecules in solution was effected for the first time by using water-soluble calixarenes. Chiral, water-soluble calixarenes changed their conformation upon inclusion of guest molecules, which was conveniently detected by the CD spectra and provided several lines of important information for the host-guest-type complex formation. Through these studies, it was shown that the moderate rigidity and the remaining conformational freedom play important roles in the complex formation with calixarene-based host molecules.

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The microwave spectra of propargyl nitrite, HC≡CCH₂ONO, and its ¹⁵N isotopic species were observed in a frequency range from 18 to 32 GHz. The ground state a-type R-branch and b-type Q-branch transitions were assinged. They were found to correspond to a cis, trans form (sp, ap form) { τ1(CO-NO) =0°, τ2(CC-ON) =180°}. The following rotational constants for the ground state were determined:
A B C
HC≡CCH₂ONO 19631.05±0.25 MHz 1794.5 0±0.01 MHz 1661.9 7±0.01 MHz
HC≡CCH₂0¹⁵NO 19419.7 8±0.20 MHz 1774.8 7±0.01 MHz 1643.61±0.01 MHz
The γ0 structure of cis, trans-propargyl nitrite was derived from a least-sq uares fit of these six rotational constants with reasonably assumed parameters for propargyl group as shown in Table 4.

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A theoretical equation which represents the effects of batch factor, β(=L/W) (cm³/g) and Cs loading, Q(meq/g) on distribution coefficient for Cs⁺, Kd(cm³/g), was derived for the adsorption of Cs⁺ from the outer solution(L cm³) on some ion exchangers of Mⁿ⁺ form(Wg), and compared with experimental results.
Kd was found to be constant with respect to β when the outer solution contains large amounts of Mⁿ⁺ initially, but it is proportional to n√β at constant Q for the adsorption from pure Cs⁺ solutions. It was also found for the adsorption from a solution containing large amounts of coexistent univalent cations except Mⁿ⁺ that Kd, being generally dependent on β, is an increasing function of β in the case of n<<2, although it becomes approximately constant with respect to β for the special case of [A⁺]E=(C_0EC-Q)/β in Eq. (14). These relationships between Kd and p have been expected to hold irrespectively of ideality of ion exchange process and found to be consistent with experimental results by assuming (∂KCS+MN+/∂β)_Q=0 (KCS+MN+: selectivity coefficient).
On the other hand, Kd is a decreasing function of Q for usual ion exhanger (n<<2) of (dKCS+MN+/dQ<<0), and it approaches a constant at infinitely small Q except for Cs⁺ adsorption from pure Cs⁺ solutions. These expectations were in accord with exprimental results except those for Zn₂[Fe(CN)₆] (ZFC). The ion-exchange behavior of Cs⁺ on ZFC was specific in its increasing tendency of Kd with Q and its high Kd value at a relatively large value of Q for the adsorption not only from pure Cs⁺ solutions but also from a 3 mol⋅dm^-3 NaNO₃solution. These findings indicate that ZFC might be preferable as an inorganic ion exchanger for the separation of Cs⁺ by a batch process from a highly concentrated solution of NaNO₃.

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In order to obtain basic data for preparing of noble metal-coated electrodes, the decomposition processes of iridium chlorides such as H₂IrCl₆⋅6H₂O, IrCl₃ and IrCl₄⋅H₂O and ruthenium trichloride, RuCl₃⋅nH₂O, and also the alcoholic solutions of these chlorides were studies by means of TG, DTA. and X-ray diffraction. Although H₂IrCl₆ decomposed stepwisely according to the order of H₂IrCl₆⋅6H₂O→IrCl₄→IrCl₃→Ir→IrO₂, IrCl₄ separately prepared decomposed in a different way from IrCl₄ detected under the heating process of H₂IrCl₆. A small difference in the crystalline structure would cause a difference in the process of decomposition. Addition of an alcohol like-l-butanol (n-BuOH) to the chlorides remarkably decreased the decomposition temperature and the matallic Jr was taken out below 450°C and IrO₂ was obtained above 450°C.
From RuCl₃, under air, matallic Ru was obtained neither in the presence nor in the absence of n-BuOH, but Ru0₂ was taken out directly above 500°C. Under the atmosphere of Ar, Ru was easily taken out by heating RuCla dissolved in n-BuOH.

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In order to obtain high-performance noble metal supporting electrodes by the thermochemical method, studies were made on thermal decomposition processes of rhodium chloride and palladium chloride and their alcoholic solutions. When RhCl₃ alone was heated, the decomposition occurred at the temperature higher than 700°C, giving Rh₂O₃ as a final product. Though the rhodium oxide is a very effective electrolytic catalyst, it is not profitable to obtain it under the conditions of such high temperature. Therefore, an attempt was made to dissolve such chlorides in 1-butanol (n-BuOH) for ' the thermal treatment. The decompositon temperature was decreased and Rh₂0₃ was obtained at 500°C through the formation of Rh metal. By heating the alcoholic solution in Ar, Rh metal was also obtained at 300°C.: On the other hand, a high temperature such as 600°C was required for decomposition of PdCl₂ to Pd metal. The decomposition temperature was lowered by addition of allyl alcohol, , and PdO, as an effective electrolytic catalyst, was obtained above 400°C.

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In order to improve the performance of catalytic metal-coated ele ctrodes, TG, DTA and Xray diffraction 'studies were made on the thermal decomposition processes of binary metal chlorides, i. e., Pt-Ir, Pt-Ru and Pt-Rh systems solved in 1-butanol. The temperature of thermal decomposition to metal was lower for various composition ratios of Pt to Ir than those of the individual metal chlorides for the Pt-Ir system, and was in between for Pt-Ru and Pt-Rh systems.
By decomposition of the binary chloride mixtures, solid solutions were obtained in all these systems. However, as the solid solutions were not well crystallized, a part of Ir, Ru, and Rh was oxidized to Ir0₂, RuO₂ and Rh₂0₃ when heated at higher temperatures than the decomposition temperature.
Electrodes su pported by the binary catalysts on Ti metal were prepared by the thermal decomposition method, and were examined for their electrolytic characteristics. Rhodium and Ru, in the solid solution, were dissolved by multiple cyclic potential sweeps and the resulting Raney-Ni type spongy surface served as high roughness Pt electrodes.

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Effects of adsorbed water on the proton conduction in antimonic acid are discussed on the basis of complex impedance analyses (Fig.1) as well as water sorption isotherms. It was possible to separate the resistivity associated with the intergranular contact from those associated with the bulk and outer surface of individual granules by applying a Cole-Cole plot technique to the samples equilibrated at various water vapor pressures at 60°C (Fig.2). Comparison of these results with those obtained for a Cs⁺-exchanged sample (Fig.4) evidences estimation that proton conduction through the bulk (channels) is more important than or at least comparable with that through the outer surface, depending on the water vapor pressure (Fig.5). The water sorption isotherms (Fig.6) indicate that water is sorbed in to the channels of antimonic acid to far larger amounts than onto the outer surface. The protonic conductivity increased first with increasing amounts of sorbed water, while no further increase was observed after condensation of water in the channel began. Activation energies for conduction (Fig.9) suggest that the proton conduction mechanism may change from a hopping type to a Grotthus type with an increase in the amounts of adsorbed water.

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The effect of magnetic field on the viscosity of hematite colloid was investigated. Our experimental results and theoretical considerations revealed that although the hematite parti cles have strong magnetic moments enough to orient along the external magnetic field, the moments are not large enough to cause aggregation in dilute electrolyte aqueous solution. Namely, the magnetoviscous effect of hematite colloid was not caused by the aggregation due to the magnetic interaction. The effect could be accounted for by the hindrance to paricle rotation caused by the magnetic torque.

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Synthesis of 2-methyl-2-propanethiol was studied by the catalytic reaction of isobutene with hydrogen sulfide. Active alumina catalyst was most effective for this reaction, and 2methy1-2-propanethiol was afforded at high yields over 90% by use of an active alumina catalyst under the optimum conditions.
The conversion of isobutene increased proportionally with an increase in the acid amount of the catalyst, and at acid amounts above 0.8 meq.⋅g^-1, the activity for this reaction reached the highest level.
Results obtained by use of Neobead C catalyst, an active alumina from Mizusawa Chemical Co., Ltd., showed that it was necessary to treat the catalyst at 500-700°C prior to use in order to develop its highest acid amount.
In a fixed bed reactor at 80°C with a space velocity between 120 h^-1 and 480 h^-1, 2-methyl2-propanethiol was obtained in a high conversion (above 95%) and a high selectivity (above 93%).
Using a moving bed reactor with a continuous supply of the fresh catalyst, 2-methyl-2propanethiol was produced in a high yield of 88% throught the reaction period (32 h) giving a stationary activity of 1.3 kg/l⋅cat⋅h as STY.

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Glass-forming region were determined in the Mg0-Al₂0₃-B₂0₃ system by the melt quenching method. Phase separation occurred at B₂0₃ rich compositions. Raman spectroscopy and IR spectroscopy measurements revealed that boroxol ring moieties exist at the B₂0₃ rich compositions and that diborate moieties of 4-fold coordinated boron exist at MgO rich but Al₂0₃ poor compositions. Pyroborate or orthoborate moieties of 3-fold coordinated boron were found at MgO rich compositions in the ternary systems. With the increase in the Al₂0₃ content, the concentration of diborate is reduced and Al0₄-tetrahedra are formed. The chemical shift measurements confirmed the variation of the coordination number of Al³⁺ ion in the Mg0-Al₂0₃-B₂0₃ system. From the comparison between the Mg0-Al₂0₃-B₂0₃ and CaO-Al₂0₃-B₂0₃ systems, it was I concluded that Mg0-Al₂0₃-B₂0₃ system has not formed a continuous network of 6-membered rings consisting of Al0₄-terahedra.
The variations of the peak shifts associated with pyroborate or orthoborate moieties suggested that Al³⁺ ions might in part be incorporated in these moieties. The smooth variation in density and refractive index of the glass with composition suggested that the structure changed continuously with composition.

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Reactions of 9 H-xanthen-9-one, 9 H-thioxanthen-9-one, 9 H-fluoren-9-one, 9(10 H)acridinone, anthraquinone and anthrone with ammonia, primary amines and secondary amines in the presence of titanium tetrachloride were studied.9H-xanthen-9-one, 9H-thioxanthen9-one and 9-fluoren-9-one reacted with ammonia and methylamine to give the corresponding 9-imino compounds, while the reaction with secondary amines afforded 9-amino compounds.9(10 H)-Acridinone reacted with secondary amines to give N, N-dialkyl-9-acridine amine. The reactions anthraquinone with ammonia, and secondary amines gave 9, 10-anthracenediol, and 9, 10-diaminoanthracenes respectively. Anthrone reacted with ammonia to give 10-aminoanthrone, and with secondary amine to give 9, 10-diaminoanthracene.

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For the purpose of clarification of the factors influencing the Diels-Alder (DA) reactivity of 2-pyrones and the stability of the DA adducts, the DA reactions of four 2-pyrones with N-substituted maleimides were investigated. Wher as the reactions of methyl 2-pyrone-5carboxylate (MP) with N-substituted maleimides only gave endo-DA adducts [1], those of 2-pyrone [1] and ethyl 4, 6-dimethyl-2-pyrone-5-carboxylate (EP) with the maleimides gave ( I) and 1: 2 endo-endo-D A. adducts [2] which were formed through decarboxylation of the corresponding [4+2] adducts, followed by, addition of another molecule of the maleimides. On the other hand, the reactions of 4, 6, dimethy1-2-pyrone (DMP) afforded, only [2] even under mild conditions.
The reactiv ity of 2-pyrones with maleimide diminished in order; DMP>P>EP>MP, showing that electron-rich 2-pyrones are more reactive than the electron-defficient ones. However, the acceleration effect of 4, 6-dimethyl groups seems to be smaller than the deceleration effect of 5-ethoxycarbonyl group. The reactivity of MP with N-substituted maleimides diminished by more electron-withdrawing N-substituents, suggesting that a 5-niethoxycarbonyl group on 2-pyrone makes the 2-pyrone an inverse electron-demand manner even in the reaction with maleimides.
The thermostability of [1] was found to be enhanced by an electron-withdrawing substituent of 2-pyrone at 5-position and to be decreased by 4, 6-dimethyl groups.

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The mechanism of the oxidation of deoxybenzoins by cobalt(III) acetate has been studied in acetic acid under nitrogen through product analysis and kinetic measurement. The main products were benzoin acetate and benzil. The ratio of the two products increased with an increase in the ratio of the initial concentration of cobalt(III) acetate to that of the substrate. The rate of oxidation of deoxybenzoins was of second order in cobalt(III) acetate, of inverse first-order in cobaltan acetate and of first order in the substrate. It increased on addition of sodium acetate. The Hammett plots for substituents in benzoyl moiety gave straight lines in the presence (p= +1.03) and absence (p=-0.60) of sodium acetate, while both electron-releasing and -withdrawing substituents in benzyl moiety accelerated the reaction in both media. Oxidation of benzoin, which was an intermediate to benzil, was also studied under similar conditions. The rate was of first-order in both benzoin and cobalt(III) acetate and was independent of cobalt(II) acetate. These facts are explained in terms of competitive reactions between metal-assisted enolization of ketone and direct electron transfer from benzene ring in benzyl moiety followed by the departure of a benzylic proton.

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The dipole moments were measured for 1, 1′-bis(4-chlorophenyl)-, 1, 1′-bis(4-chloro-2methylpheny1)- and 1, 1′-bis(3, 5-dichlorophenyl) ferrocene.1, 1′-Bis(4-chlorophenyl)ferrocene was concluded to be an equivalent mixture of five antiprismatic conformers, but on the other compounds, the rotation of cyclopentadienyl rings was considerably restricted. For example, the intramolecular repulsion between the substituents was recognized on 1, 1′-bis(4-chloro-2methylphenyl) ferrocene, whereas the attractive force was induced on 1, 1′-bis(3, 5-dichlorophenyl)ferrocene. Further, the relation between the conformation and the proton chemical shift values was also discussed.

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Preparation of ion-exchange COPNA resin was carried out by sulfonation of COPNA resin with conc. sulfuric acid.
The COPNA resin, used was prepared from the mixture of pyrene and phenanthrene added 1, 4-benzenedimethanol (PXG) as a crosslinking reagent.
The optimum conditions of sulfonation was det ermined. The ion-exchange capacity of the resulting resin was measured and then the resin was examined for thermostabilities.
The highest ion-exchange capacity of ca.3.5 meq/g was given to the post-cured resin at 200°C for 1 h when the resin was ground under 105 urn and sulfonated with conc. sulfuric acid in continuously stirring at 120°C for 2 h.
Observation of resin particle surface an d its cross section shows that sulfonation proceeds from particle surface to interior side with reaction time to cause cracking like annual ring. This ion-exchange COPNA resin is outstanding in wettability and not swelled in water. Consequently, the rate of ion exchange is fast.
The resin in boiling water for 1 h decreas ed ion-exchange capacity by only 10%.

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Catalytic combustion of methane was performed over monolithic honeycomb catalysts composed of mixed metal oxides. Since perovskite catalysts were significantly deactivated due to sintering into agglomerates and reaction with cordierite at high temperature (Figs.5 and 6), the complete combustion was not achieved at a high flow rate. In contrast, a single phase honeycomb composed of Mn-substituted hexaaluminate was successfully demonstrated for the high-efficiency catalytic combustion (Fig.4). The temperature of the catalyst bed was constantly maintained at 1200°C during the operation. Manganese-substituted hexaaluminate had excellent heat resistance in maintaining the large surface area over 20 m²/g after calcination at 1300°C. The large surface area was very effective in stabilizing and promoting the fuel-lean homogeneous combustion which occurs in a catalyst bed. It also became evident that the formation of thermal NO^x in the combustion process is greatly suppressed by the use of the Mn-substituted hexaaluminate catalysts (Fig.7).

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The decoloration reactions of 1-(4-sulfo-1-naphthylazo)-2-naphthol-3, 6 -disulfonic acid (SNND) and 1-(2-hydroxy-4-sulfo-1-naphthylazo)-2-naphthol-3, 6-disulfonic acid (HSNND)by ozone were studied in aqueous media, and the effects of chelate formation of the dyes with Cu(II), Ca(II) and Mg(II) ions were examined. The decoloration of HSNND by ozone was retarded by the chelate formation of HSNND with the metal ions, and the degree of retardation increased with an increase of the value of the formation constant of HSNND-M(II)chelates. The decoloration rate of SNND by ozone, however, increased in the case of the chelate formation with Cu(II). Difference between the behavior of HSNND-Cu(II) and that of SNND-Cu(II) in the ozone decoloration seems to be partly due to the difference in the steric hindrance of these chelates for an ozone attack.

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As the safe and complete dehalOgenation process of environmentally hazardous organohalogen materials, we have applied the reductive removal method of naphthalenide (naphthalene radical anion) and the Birch type reduction to organic halogen atoms incorporated in poly(vinyl chloride) (PVC) and poly(chlorotrifluoroethylene) (PCTFE). In these processes th e organic halogen atoms were safely converted into inorganic alkali halides effectively. By a proper treatment, PVC was transformed into a colorless solvent-soluble polymer which was f ree of chlorine. PCTFE was also completely and rapidly dechlorinated (100%) and even the organi c fluorine. atoms were removed up to the extent of 96% by the treatment with naphtha lenide at 0°C for 60 min.

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The variation of copper(II)-complexing capacity(CuCC) of intermediate products during the aerobic digestion of glucose and phenol was studied in relation to the concentration of amino acids (free amino acids) and proteins (bound amino acids).
The organic substrate, glucose, diminished sharply after the initial induction period with the increase in turbidity which is the index of the biomass. At the maximum turbidity, the consumption of glucose had almost finished and most of glucose prQbably changed to biomass and/or metabolic products. After the maximum, turbidity decrease due to the autolysis.
A linear relationship was observed between amino acid (free and bound) concentra tion and the CuCC. In addition, the CuCC varied in a similar way to the amino acid concentration. The data during autolysis did not show the above relationships.
The experimental results for phenol were just th e same as thoes for glucose.
In the practical sewage treatment works, the same relationships were observed between the amino acid(free and bound) concentration and the CuCC of the effluent and influent waters of the aeration tank. Consequently, the concentration of amino acids and/or proteins should be taken into account in evaluating the CuCC of the intermediate products in aerobic digestion of sewage.

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The kinetic measurement has been made for bromination of calcium oxide and hydrolysis of calcium bromide in the UT-3 therpochemical water-decomposition cycle. In this cycle, the Ca compound is used repeatedly between bromide and'oxide. The compound; therefore, must be distributed in a solid structure being composed of inert materials. Four kinds of candidate materials such as SiO₂, Al₂0₃, Ti0₂, and Zr0₂ were mixed with CaO powders and examined their reactivities in several cyclic runs. Pellets with TiO₂ showed the best reactivity and reproducibility. Also, it was found that the structural change of pellet occurs in cyclic operation due to the difference of molar volume between reactant and product solid, resulting in the influential effect on the overall conversion.
Applying the homogeneous model, th e hydrolysis rate of calcium bromide rv was given by
where C_H20 is molar concentration of H₂0, C⁰_CaO is initial molar concentration of CaO, and X is conversion based on the bromination.

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We measured temperature and the concentrations of stable species in a methane/air coaxial laminar diffusion flame, and simulated the chemical reactions taking place in this flame by means of a detailed chemical reaction model based on the experimental results.
The air is entrained towards the center line just above the burner rim p roducing a premixed gas mixture as shown in Fig.9. Fig.4 shows the reaction mechanism in this premixed region. Methane is oxidized here through the Cc-route which consists of the steps of CH₄→CH₃O→HCH0→CHO→CO→CO₂. The active species and the thermal energy produced in a very short time hold the whole flame on the burner rim.
In thel uminous region, methane is pyrolyzed through t he C₂-route, which progresses as CH₄→CH₃→C₂H₄→C₂H₃→C₂H₂ Consequently more than 90% of methane is once converte d to acetylene and then oxidized as shown in Fig.6. Fig.8 shows the dominance of the C₂-route in this flame, and Fig.7 also suggests the important role of acetylene because the region of its presence is overlapped with the luminous region.
The oxygen, which was entrained near the nozzle and left unused here, produces hydroxyl radicals in the luminous region. The hydroxyl radicals are consumed by the dehydrogenation of methane. The entrained oxygen hence accelerates the first step of methane combustion as shown in Fig.10 and, therefore, activates all the reactions occurring in this flame including soot formation.

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The catalytic activities of ultramarine blue, violet and pink for the dehydration of 2-propanol were examined at 473 K using a closed circulation system. The order of the activity of these ultramarines was as follows; ultramarine pink>ultramarine violet>>ultramarine blue. Infrared spectra of these ultramarines indicated that there existed the acidic hydroxyl groups and ammonium ions on the surface of ultramarine pink and violet. It was concluded that high activities of ultramarine pink and violet for the dehydration of 2-propanol were attributed to the existence of the Bronsted acid sites on the surface of these ultramarines.

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Synthesis of BaSn(B0₃)₂ by solid-state reactions among BaCO₃, B₂0₃ and SnO₂ during 500-1150°C and sintering of the synthetic powders over 1000-1150°C have been st udied. The reaction seems to proceed as follows: (1) formation of BaB₂0₄ by a reaction between BaCO₃ and B₂0₃ between 500 and 800°C, (2) formation of BaSn(B0₃)₂ by a reaction between SnO₂ and BaB₂0₄ between 800 and 1900°C and (3) increase of SnO₂ content due to a decomposition of BaSn(B0₃)₂ beyond 1000°C. Dense specimens were obtained by calcination at 950°C and sintering between 1100 and 1150°C. The maximum electric resistivity of sintered BaSn(B0₃)₂ was 7.3×10¹⁴Ω.⋅cm for the present experimental conditions.

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2, 3, 5 -Trimethyibenzoquinone (TMBQ) was prepared in about 90% yield through anodic oxidation of.2, 3, 6-trimethylphenol-4-sulfonic acid (TMPS) using 3.2 F/mol of electricity under a constant current density (8 mA/cm²) with a graphite plate as an anode in 40% aqueous acetone containing sulfuric acid [0.42 mol/l] in a divided cell, or in a two-phase reaction.

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