The acidity of silanol groups on the surface of silica sol particles has been investigated by potentiometric titrations of the sol in KNO₃ solutions at 25°C. The total number of dissocia- ble surface sites per unit surface area was 2.1inm² at an ionic strength of 0.1 mol/l. The value of intrinsic acidity constant (K₂⁰) of the surface group ≡SiOH was pK₂⁰=7.0, which indicated that silica was more acidic than monosilicic acid. The intrinsic acidity constant (K₁⁰) of the surface group ≡SiOH₂⁺ was estimated to be pK₁⁰=0 from the values of pK₂⁰ and the point of zero charge (pzc=3.5). The value of surface fraction (3 × 10^-4) of each charged site at the pzc shows that the surface of silica consists essentially of a neutral site at the pzc. Oxides were classified into four groups according to the values of pzc and ΔpK(=pK₂⁰ -pK₁⁰), which are the parameters of the surface acidity of oxides. The adsorbability of alkali metal ions was in the order C_s⁺>Li⁺ for silica having large values of ΔpK and small values of pzc.

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The effect of poly (vinylpyrrolidone) (PVP) and sodium dodecyl sulfate (SDS) on flocculation and dispersion of kaolinite suspension in water was studied. The mean diameter, d_m, of kaolinite particles in suspension was measured by a sedimentation balance method under the various concentrations of PVP and/or SDS. Flocculation was observed when solutions with PVP concentrations less than O.0025% were added, but it was found that the floc of kaolinite was re-dispersed by the addition of SDS, whose concentration required for the re-dispersion increased with increasing concentration of PVP as the flocculating agent. It was also found that the required concentration of SDS depends on the preparation method for the kaolinite suspension; the required concentration of SDS, when a PVP solution was added to kaolinite before the addition of an SDS solution (method I ), was larger than that in method II, in which the adding order of PVP and SDS was reversed. These relations are shown in Figs.4 and 5.
In high concentrations of PVP, where PVP acts as a dispersing agent for kaolinite, d_m had both minimum and maximum values with increasing SDS concentration when the suspen- sion was prepared by method I at a constant PVP concentration. On the other hand, d_m had neither maximum nor minimum but decreased with increasing SDS concentration in the case of the preparation method II. The co-operative dispersing effect of PVP and SDS was also observed in the method II. These relations are shown in Figs.4 and 5, where the contour lines of d_m are given as a function of the concentrations of SDS and PVP.
The equilibrium pH of the kaolinite suspension increased with the increase of the concentration of SDS, and increased remarkably in the presence of PVP and SDS, as shown in Fig.6. The results were explained by the cooprative and/or competitive adsorption of PVP and SDS on the kaolinite surface and the subsequent formation of a complex of PVP with SDS.

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The catalytic activity for NO decomposition over the mixed catalysts of Pt/SiO₂. Al₂O₃, and metal oxides, or over the Pt catalysts supported on metal oxides was studied by pulse technique. The reduction of the catalysts remarkably enhances the NO decomposition. But the oxygen produced during NO decomposition is strongly adsorbed on the catalyst surface resulting in a decrease in catalytic activity. After catalytic activity reaches the low stationary value, the formation of NO₂ probably at a low temperature part is suggested by examining material balance of nitrogen. In the mixed catalysts, any metal oxide does not show promoting effect on the catalytic activity at the stationary state.
However, the catalytic activities for NO decomposition over the Pt catalysts supported on metal oxides, which were prepared from [Pt₁₅(CO)₃₀].2N (C₂H₅)₄/acetone or [Pt (NH₃)₄](NO₃)₂/H₂O solution, are significantly different depending on catalyst. The metal oxide supports show the following order for the apparent effect on the catalytic activity: ZnO, Cr₂O₃>γ-Al₂O₃, Co₃O₄, NiO>MgO, Fe₂O₃, SiO₂, SiO₂, Al₂0₃, Pr₆O₁₁, Mn₂O₃>CuO>V₂O₃. The N₂/N₂O ratio and apparent activation energy (3∼19 kcal/mol) are also widely different depending on catalyst.
In order to compare the effect of metal oxide support, the dispersion of Pt was examined in some Pt catalysts supported on γ-Al₂O₃, SiO₂, Al₂O₃, MgO, SiO₂, ZnO. It was found that the specific activity for NO decomposition increases remarkably with increasing Pt particle size.

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Beckmann rearrangement of acetone oxime over B₂O₃-based binary metal oxide catalysts was studied with a continuous flow reactor at atmospheric pressure. For investigation of the relation between the catalytic activity and the acidity, DTA measurements and butylamine titration were also carried out. The best condition for this reaction was obtained at a reaction temperature of 350°C and at a contact time of 47 g-cat/mol/hr. The high activities for the generation of N-methylacetamide were observed in P₂O₅-B₂O₃, Al₂O₃-B₂O₃, and Si02-B₂O₃ catalysts, which had many acid sites of -3.0 > H₀> -8.2. On the other hand, the formation of acetonitrile, which was a by-product, was affected by acid sites of.H₀>-3.0. It was shown that the contents of B₂O₃ in the catalysts also affected the rearrangement activity greatly and had the optimum value; the activity decreased for higher contents of B₂O₃.

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Vapor-phase catalytic oxidation of isobutylene over supported copper and bismuth arsenate and phosphate has been investigated with reference to the nature of oxygen species incorpo- rated into methacrylaldehyde formed. The reaction of isobutylene with Cu₂O at 340°C in the absence of gaseous oxygen did not give methacrylaldehyde in contrast to the case with fully oxidized copper catalyst (CuO-SiC). However, when the adsorbed oxygen species was eliminated from the copper catalyst, a rapid decrease in selectivity for methacrylaldehyde formation was observed. As Cu₂O and the copper catalyst have hydrogen abstracting property, adsorbed oxygen species would be considered to be that incorporated into methacrylaldehyde. On the contrary, the reaction of isobutylene with catalysts containing bismuth and having no adsorbed oxygen species at 550°C in the absence of gaseous oxygen brought about methacrylaldehyde, benzene, and toluene; which showed incorporation of lattice oxygen into methacrylaldehyde. Furthermore, a preferential formation of methacrylaldehyde or the aromatic hydrocarbons was observed in the reaction of isobutylene with and in the oxidation of isobutylene catalyzed by BiAsO₄ and BiPO₄ or Bi₂O₃-Cu₂O, respectively, and the ratio of yield (methacrylaldehyde/ aromatics) increased with increasing strength and amount of acid existing on the surface. Formation of methacrylaldehyde and furan was observed in the co-oxidation of isobutylene with butadiene catalyzed by Cu₂O-SiC in contrast to that catalyzed by CuO-SiC. Based on these findings, mechanism of the incorporation of oxygen species into methacrylaldehyde was discussed. It was proposed that the incorporation proceeded through a nucleophilic addition of lattice oxygen O^2- or adsorbed electronegative oxygen species to, π-allyl, formed on Bi³⁺ in the case of catalysts containing bismuth, or to π-allyl, formed on Cu⁺ in the case of copper catalyst, respectively.

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The relation between surface structure and catalytic properties of ZnO for propylene oxidation was studied at 500°C using three kinds of the oxide particles; needle-like, granular and plate-like particles. Needle-like ZnO (Fig.2) was obtained by the air oxidation of zinc vapor. The needle axis was found to be parallel to the c axis of the crystal. The particles in this shape were unstable and transformed into particles in granular shape by prolonged heat treatments at 500∼600°C, as shown in Fig.3. However, change in the morphology was very. small in the reaction at 500°C within an hour. Granular catalysts of three different origins were used; commercial ZnO (Kadox 25), ZnO prepared by the thermal decomposition of zinc acetate and of zinc oxalate. Plate-like ZnO (Fig.5) was obtained by the thermal decomposition of the mist particles of zinc nitrate solutions at 600°C. Electron diffraction analysis indicated the plane of this particle was perpendicular to the c axis.
Results on the catalytic reactions were shown in Figs.8∼10 and Table 2. All samples showed some activities for allylic oxidation forming 1, 5-hexadiene and benzene and for complete oxidation. At a low conversion level where enough gaseous oxygen was present, the morphology of ZnO did not play an important role in the catalytic activity, and the selectivity for allylic oxidation was less than 15% in every case. At a high conversion level where the effective surface of the catalyst was reduced, on the other hand, the catalytic properties were greatly influenced by the morphology. Needle-like catalysts were highly active for the formation of benzene, and their selectivity was about 40%. Plate-like catalysts were not very active for the formation of benzene, and the selectivity was less than 5%. Three granular catalysts showed activity and selectivity slightly higher than plate-like catalysts. With these results, the active sites on ZnO particles for allylic oxidation were concluded to be Zn²⁺ ions exposed on the plane parallel to the c axis, for example, {1010} where the reduction takes place.

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The catalytic effect of magnesium ion on the reactions of a NADH-model compound with carbonyl compounds has been studied electrochemically.1-Benzyl-1, 4-dihydronicotinamide (BNAH) was used as a NADH-model compound and ethyl benzoylformate, benzil, 2-acetylpyridine, or 4-acetylpyridine as a model substrate. Relative reactivity of the substrate with BNAH, studied in the homogeneous phase reaction, depends not only on the reduction potential of the substrate, but also on the complex formation between the substrate and magnesium ion. The reaction proceeds via such a bridged complex as [BNAH-Mg²⁺-substrate], and is classified in a Michaelis-Menten type.

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The growth of ZrN crystals on a graphite plate from a gas mixture of ZrCl₄, H₂ and N₂ was investigated at the temperature range of 600∼4400°C. Coatings became deposited at 600∼1400°C and whiskers grew at 1100∼1300°C on the coatings. The growth rate of whiskers showed a maximum at the initial gas composition of [H₂]0=50∼80%, [N₂]₀=20∼50% and [ZrCl₄]₀= 0.6∼0.9% (total pressure: 1 atm). The axial growth rate showed a maximum against [ZrCl₄]₀. The maximum growth rates observed were ca.1.3 mm/hr in the axial direction and ca.0.04 mm/hr in the radial direction. ZrN whiskers grew along ‹111› or ‹100› direction and were predominantly bounded by {110} surfaces. The lattice constant of the whisker showed the possibility that the whiskers grown above 1100°C were contaminated with carbon.

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Thirty-seven pyrimidine reagents have been tested for the spectrophotometric determination of iron(II).2-Dimethylamino-5-nitroso-1, 4, 5, 6-tetrahydropyrimidine-4, 6-dione (DNPD) having the functional group, -C(=0)-C(NO)-C(=O)-, in the pyrimidine ring reacts with iron(II) to form water-soluble blue complex. DNPD-iron(II) complex has an absorption maximum at 660 nm against a reagent blank and shows a constant absorbance over the final pH range from 9.5 to 10.5. Beer's law holds over the range from 0 to 3 μg/ml of iron(II) at 660 nm; the molar absorptivity of the complex and the sensitivity for log(l₀/l)=0.001 are 2.40 × 10⁴l.cm^-1.mol^-1 and 2.32 × 10^-3μg.cm^-2, respectively. The coefficient of variation was 0.42% for 1 μg/ml of iron(II). A large amount of cobalt(II) and copper(II) interfered with the determination, but could be masked by the addition of 1N hydrochloric acid. The ratio of iron (II) to DNPD in this complex was found to be 1: 3 by the continuous variation method.

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It was found that porous spherical silica gel for high-performance liquid chromatography was formed by emulsifying silica sol in the combined medium of polar and non-polar solvent such as alkyl alcohol and liquid paraffin. The suitable oarbon number of alkyl alcohols is from C₄ to C₉ and good shaped spherical silica gel was obtained in the range 20∼60% (v/v) of the alkyl alcohol to the liquid paraffin. Silica sol was prepared by mixing sodium silicate solution and hydrochloric acid which are both cheap and commercially available easily. The particle size of the spherical silica gel can be controlled by the stirring speed of a stirrer and also by the viscosity of the mixed organic solution used for dispersing media. Figures 2 and 3 show their effects on particle size distribution and mean particle diameter, respectively. The pore structure of spherical silica gel, which is characterized in terms of specific surface area, pore volume and pore diameter, can be controlled by heating or acid treatment during hydrogel state. By the heating treatment the pore of the silica gel is enlarged and the acid treatment after heating can make it larger. The pore structure is one of the most important factors for adsorption chromatography. By controlling the pore diameter of silica supports, various kinds of samples can be applied to the adsorption chromatography using silica gel supports. Compared with irregularly-shaped silica gel supports, the spherical silica gel supports prepared by the proposed method showed higher column efficiency as shown in Fig.7.

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¹³C NMR spectra of seven β-diketones were measured in chloroform-d (CDCl₃) and dimethyl-d₆ sulfoxide (DMSO-d₃) and diffrences in carbonyl ¹⁸C chemical shift between these two solvents were found to change with the groups substituted at 1 or 3 position (Table 1). On the basis of the correlation between the diffrences in the carbonyl ISC chemical shift and the dissociation constant (Fig.1), it may be considered that the differences between the carbonyl ¹⁸C chemical shift in CDCl₃ and those in DMS0-d₆ show the stabilities of the chelated ring of 8-diketones.

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Esterification of benzoic acid (BA) with ethylene oxide (EO) in the presence of various amines (A) was studied in organic solvents. On the basis of the isolation of the intermediate and kinetic data, it was proved that the catalyst for the esterification was not amines them- selves but their quaternary ammonium benzoates (C₆H₅COOCH₂CH₂OH, Q) formed from benzoic acid, ethylene oxide, and amines.
The rates of formation of Q and 2-hydroxyethyl benzoate (ES) were found to be represented by the following equations:
Kinetic data showed that k_ES was larger than k_Q. Values of k_ES for esterification of several p-substituted benzoic acids with ethylene oxide followed the Hammett's equation in the range of σ value -0.27∼ + 0.78 and the ρ value was positive. This result suggests that the formation of hydrogen bond between p-substituted benzoic acid with ethylene oxide in the transition state plays an important role in accelerating the reaction.

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The reaction of some allylic alcohols in terpene field with 2, 3-dichloro-5, 6-dicyano-1, 4- benzoquinone (DDQ) has been investigated. When the allylic terpene alcohols were treated with DDQ in 1: 1 molar ratio in toluene, benzene or cyclohexane, the corresponding α, β-unsaturated aldehydes or ketones were isolated by column or gas chromatography (GC), and 2, 3-dichloro-5, 6-dicyanohydroquinone (DDQH₂) was separated by filtration from the reaction mixture. Identity of the reaction products was established by comparison of their mp, to in GC, R_f in thinlayer chromatography, MS, IR and UV spectra with those of the authentic samples.
The reaction of the bicyclic or monocyclic allylic alcohols with DDQ gave a good yield of the corresponding aldehydes or ketones. The reaction of the a cyclic allylic alcohols with DDQ in benzene or toluene yielded the corresponding aldehyde and the isomer, but in cyclohexane gave a good yield of the corresponding aldehydes in contrast with the oxidation by chromium trioxide.

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2-Hydroxyethylaminium dihydrogenphosphate (1), HOCH₂CH₂NH₂.H₃PO₄, was heated at 100∼200°C, and then the reaction mixture was separated by ion exchange chromatography. The mechanism of the conversion of ( 1 ) into 2-aminoethyl dihydrogenphosphate (3), H₂O₃POCH₂CH₂NH₂, was elucidated in terms of the following results:
( 1 ) The conversion of [1] into [3] proceeded slowly by heating (1) below 120°C. In addition to [ 3 ], small amounts of bis (2-aminoethyl) hydrogenphosphate [4], HO₂P(OCH₂- CH₂NH₂)₂, and diphosphoric acid were obtained by heating [ 1 ] above 140°C. The yield of (3) decreased linearly with molar ratio of 2-aminoethanol to phosphoric acid increasing from 0.5 to 2.0.
( 2 ) 2-Aminoethanol reacted with diphosphoric acid rapidly by heating them above 140°C to give [ 3 ] in excellent yield.
( 3 ) The amount of diphosphoric acid, obtained by heating 2-ethoxyethylaminium dihydrogenphosphate, C₂H₂OCH₂CH₂NH₂.H₃PO₄, was comparable to that of [3], obtained from (1) under the same conditions.
It was concluded that the conversion of [1] into [3] proceeded via bis(2-hydroxyethylatni- nium) dihydrogenpyrophosphate [2], (HOCH₂CH₂NH₂)₂.H₄P₂O₄, which was formed by dehy- drating two moles of [1].

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Isomeric of 5-methoxy-4, 8, 8-trimethyl-2 H, 8 H-benzo[1, 2-b: 5, 4-b']dipyran-2-one [1] and 5-methoxy-2, 2, 10-trimethyl-2H, 8H-benzo[1, 2-b: 3, 4-b']dipyran-8-one [2] were synthesized by reduction of the dihydropyranone ring of 4-methylcoumarin derivatives with sodium borohydride, followed by dehydration of the corresponding alcohol.
The ¹H NMR chemical shifts of aromatic protons of 4-methylcoumarin derivatives exhibited the trend similar to those observed in the case of 4-phenylcoumarin derivatives; each chemical shift of aromatic protons of the linear isomers appeared at a field lower (0.17∼0.27 ppm) than, those of the angular isomers.

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The catalytic reduction of p-nitrotoluene (PNT) to obtain p-toluidine (PTD) with hydrazine hydrate in the presence of active carbon and iron(III) chloride was studied kinetically.
It was found that on active carbon total Fe ions and 0.2g of hydrazine hydrate per g of active carbon were adsorbed under the reaction conditions. It was confirmed that nitrogen gas evolved quantitatively during the reaction. The intermediate product of this reaction was p-tolylhydroxylamine. From these results, the reaction was expressed by the following equations:
Ar-NO₂ + N₂H₄ → Ar-NHOH + H₂O + N₂
Ar-NHOH + 1/2 N₂H₄ → Ar-NH₂ + H₂O + 1/2 N₂
Ar=p-Me-C₆H₄
On the basis of the kinetic study, following rate equation was suggested.
where, C is the amount of active carbon.

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The chirality of cholesteric liquid crystals of concentrated polyglutamates solutions has been determined by measuring the sign of induced circular dichroism (CD) of Acridine Orange, an achiral dye dissolved in the cholesteric mesophase. The samples used in this study are poly[γ- (benzyl, butyl, hexyl and octyl)-L-glutamates] abbreviated as PBLG, PBuLG, PHxLG and POcLG respectively and their characterizations are shown in Table 1. The solutions were introduced slowly into a quartz cell having 1 mm path length. The CD spectra were recorded on a Jasco J-20 A spectropolarimeter. The helical sense of cholesteric mesophase was presumed by reference to the study of CD spectra due to the selective reflection of helical structure in solid films of polyglutamates.
The chirality of polyglutamate liquid crystals was found to depend on temperature, concentration, solvent and side-chain length of the polyglutamates as follows (see also Table 3).
( 1 ) PBLG and PBuLG solutions in 1, 2-dichloroethane, as well as in dichloromethane form left-handed cholesteric mesophase at room temperature when the volume fraction of the solute is below 0.164. ( 2 ) When the volume fraction of the solute is above 0.191, the cholesteric structure of PBLG in 1, 2-dichloroethane reverses its helical sense. ( 3 ) In the solutions of PBLG in m-cresol and of PHxLG in chloroform, the chirality of cholesteric structure changes sign from the right-handed direction to the left-handed one through nematic structure as temperature increases. ( 4 ) POcLG solution in chloroform forms left-handed cholesteric mesophase in contrast to that of PBuLG in the same solvent.

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Poly (^α-methacryloyl-L-histidine) (PMHis) and ^α-pivaloyl-L-histidine (PHis) were synthesized and used as catalysts for hydrolyses of p-nitrophenyl esters of D- and L-phenylalanine (Phe-PNP), N-methoxycarbonyl-D- and -L-phenylalanine, α-isobutyl L-aspartate and acetic acid. The hydrolysis was carried out in water-ethanol (31: 1, vol/vol) mixture at 26°C. The effect of Cu²⁺ ion was also studied. In buffer solutions of pH 7.20, 8.25 and 9.31, PHis was more effective catalyst toward any substrates than PMHis. The addition of about 10% copper (II) nitrate to imidazolyl group brought about a great enhancement of the hydrolysis rates of Phe-PNP and Asp-PNP by buffer solution alone and by PHis. However, in the presence of PMHis, the effect of Cu²⁺ ion was significantly depressed. In all hydrolyses, D- and L-substrates were hydrolyzed at similar rates.

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For the purpose of obtaining catalysts with higher activity and stability for the reduction of nitrogen oxides with NH₃, the mechanism of the reduction over V₂O₅-TiO₂, V₂O₅-Al₂O₂, Fe₂(SO₄)₃-TiO₂, Fe₂(SO₄)₃-Fe₂O₃, CuSO₄-TiO₂, CuSO₄-Al₂O₂ and Cu (II) ion-exchanged Y type zeolite catalysts were studied.
The experiments were carried out using a flow reactor (I. D.: 12.0 mm) at atmospheric pressure and 200∼450°C(mainly 350°C). The amount and composition of the inlet gas employed were mainly 500 ppm NO (NO, NO₂, NO-NO₂ mixture), 667 ppm NH₃, 0∼5% O₂, and 10% H20∼N2 and the space velocity of the gas was mainly kept at 1.2 × 10⁵ hr^-1.
It was found that the rate of the equimolal mixture of NO and NO₂ to N₂ was much higher than that of NO or NO₂ and the contribution of oxygen to the oxidation of NO to NO₂ was very large for the reduction of NO with NH₃. Also, for the reduction of NO to N₂, the reduction of NO₂ with NH₃ to NO was important at the beginning of the reduction.
These results suggest that the reduction of NO proceeds at the equimolal ratio of NO and NO₂ and at the equimolal ratio of NO_x and NH₃ as well on the surface of the catalyst, regardless of the kinds of inlet NO_x or catalysts employed. On the other hand, experimental results on the stoichiometry of the reaction showed that the reaction had the following overall reaction equations:

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By using the apparatus based on the gas permeation membrane method, very dilute gas (NO, CO, CH₄ C₂H₆, or C₃H₃) was prepared, in order to calibrate air pollutant monitoring instruments. The amount of the pure source gas, permeating through the membrane (FEP teflon, thickness of 125 and 813 μ), in accordance with the Fick's gas diffusion theory, depended on the pressure of the gas and the temperature of the teflon (Figs.3∼7). It is therefore possible to prepare a desired concentration of gas from the source gas by selecting an appropriate gas pressure or temperature. A scatter of the data on concentrations of the gas, however, increased with decreasing membrane temperature and with increasing size of the gas molecule (NO<CO<CH, <C₂H₆<C₃H₃) in the case of FEP 125 (Table 1). Since the activation energy of the gas for permeation increased in the above order (Fig.8), the pre- cision of teflon temperature control was considered as an important factor to know a scatter of the data. The diffusion constants (D) and lag-times (M₀), being the parameters of gas permeability, were determined from analysis of the change in concentration with time (Fig.2 and Table 3). The time to reach steady permeation rates (T_a), closely associated with practical value of the apparatus, was estimated to be about three times as large as M₀. The variation of T_a with species of gases and change in temperature as well as in thickness of the teflon were also well elucidated in terms of both D and M₀ (Tables 2 and 3).

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When NO in the boiler flue gas is absorbed in Fe(II)-edta complex solutions, SO₂ is simultaneously absorbed by the reaction with Fe(III) hydroxo complex (Fe(III) (OH)-edta) formed in the oxidation by oxygen contained in the gas. Results of the studies of the volume of absorption in saturation and of desorption of SO₂ in the hydroxo complex solution, which was prepared by the partial oxidation of the Fe(II)-edta complex solution showed that the molar equivalent amount of SO₂ was absorbed in the hydroxo complex solution. It was also possible to control the reaction of absorbed SO₂ with Fe (II) nitrosyl complex (Fe(II) (NO)-edta) in Fe( II, III )-edta complex solutions up to a negligibly small level under the reaction conditions of temperatures below 60°C and the values of pH less than 4.2.
Pilot scale tests with a packed column showed that 95% of SO₂ in the boiler gas was absorbed and the concentration of SO₂ in the effluent was 50 ppm in the pH range from 4.0 to 4.2, if the amount of the hydroxo complex formed in the column was more than 1.2 times the amount of SO₂ in the inlet gas in molar ratio.

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The catalytic reduction of NO_x in the real flue gas from a sintering furnace, with NH3 was studied by using V₂O₅ and Fe₂O₃ catalysts supported on γ-Al₂O₃ (Fig.1). Studies were focused on the dust components in the flue gas which would be harmful to the catalyst life.
The dusts consist of such alkaline and alkaline earth metals as K, Na, and Ca (Table 1, 2). Fe and Si were also identified in the dust. The dust components gave different effects on the catalysts. Si and Ca permeated into the catalysts to diminish their micro pore structures (Fig.8, 9). while K selectively reacted with iron ions in Fe₂O₃ catalyst and in the dusts. It was observed that the amount of K in the catalysts lowered the catalytic activities (Fig.10, 11). X-ray diffraction spectra showed that K in the catalysts exists in the form of K₂Fe(SO₄)₂. By means of ion microanalyzer, K was found to permeate into the surface of V₂O₅ catalyst (Fig.5), while, in the case of Fe₂O₃ catalyst, it was concentrated on its surface (Fig.6), and then migrated in the bulk of the catalyst deeper than 150 μ from its surface (Fig.7). This fact resulted in more deactivation of Fe₂O₃ catalyst than that of V₂O₅ catalyst.
It was also clarified in this study that SO₂ in the flue gas less affected the catalytic activities than the dust components. The poisoning effect of the dust components was also elucidated separately.

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The electrical conductivity changes of SO_x-chemisorbed FeOOH with pretreatment temperature (30∼100°C) were compared with those of pure FeOOH crystals. Above 60°C of pretreatment temperature, the increase in conductivity of SO₂-chemisorbed samples was larger than that of pure samples for all FeOOH. The increase in conductivity of SO₂-chemisorbed γ-FeOOH with the rise of pretreatment temperature was more noticeable than α- and β-FeOOH. Chemisorptive sites for SO₂ are surface oxygens for α- and β-FeOOH, whereas the oxygens in hydroxyls on surface for γ-FeOOH. The formation of oxygen defects in γ-FeOOH was promoted by the detachment of the chemisorbed SO₂ during the heat treatment.

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The residual carbon, formed upon pyrolysis of graphite fluoride, is amorphous in analogy with carbon black or petroleum coke, but has smaller interlayer spacing and larger specific surface area due to its microporous structure than amorphous carbon.
Upon direct fluorination of the residual carbon a more crystalline graphite fluoride was obtained even at a low temperature than the case of amorphous carbon. The reactivity of the residual carbon with fluorine gas at a room temperature was comparable to that of active carbon, and the graphite fluoride obtained from the residual carbon has a similar high ther- mostability to that of graphite fluoride, obtained from graphite at a high temperature under an atmosphere of fluorine gas.

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Three isomers of iminodiacetato(L-ornithinato)cobalt(III) have been prepared and their CD spectra are analysed and understood in terms of configurational and vicinal effects. These three isomers isomerized in water in the presence of active carbon. The measurement of the molar distribution of these isomer after equilibrium revealed that mer-cis N existed almost 100% and mer-trans N and fac isomers have not existed within experimental errors.

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9-Oxoisologifolene [6] was synthesized from longifolene [1] and isolongifolene [2].
The treatment of [1] with molecular oxygen for 32∼48 hr at 110∼130°C in polar aprotic solvents (DMSO, DMF and HMPA) yielded 9-oxoisolongifolene [6] as a major product accompanying longicamphene hydrate [3], longi-β-fenchyl alcohol [4], and longiborneol [5] as minor products. Similarly, the olefin [2] selectively gave [6] in good yield.

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Air oxidation of p-menthadienes (1, 4( 8 )-p-menthadiene [ 1 ], 2, 4( 8 )-p-menthadiene [2], 1, 3-p-menthadiene [3], 1, 4-p-menthadiene [4]), or p-cymene [ 5 ] at 100°C in dimethyl sulfoxide (DMSO) selectively gave p-methylacetophenone [7]. It has been shown that the formation of [7] from [1] or [2] was accompanied by the appearance of 1-methyl-4-isopropenylbenzene [6] as an intermediate and that the formation of [7] from [3] or [4] proceeded via [5].
In N, N-dimethylformamide (DMF) or hexamethylphosphoric triamide (HMPA), the oxidation of [1] or [2] predominantly gave 2- (p-methylphenyl)-2-propanol [8] whereas the oxidation of[3] or [4] merely gave [5].

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The substituent effect on the reaction of (diethylamino)dialkylarsine and -stibine with ethylene carbonate has been studied. In the case of the aminoarsines, the rate varied according to the class of the alkyl substituent on arsenic atom in the order: secondary alkyl>primary alkyl>methyl. The correlations with the Taft's equation were fairly good in each class of the alkyl substituents, and p value was calculated to be positive. The results are consistent with the four-centered mechanism. In the case of the aminostibine, there was no acceleration or retardation of the rate depending on the class of the alkyl substituents. These results show the fact that the hyperconjugation effect of the substituent on the electron density of group V element decreases with the increase of the atomic size of the group V element.

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