The semiconducting behavior of silver-doped barium titanate ceramics heated at elevated temperatures was investigated. The anomaly of positive temperature coefficient of resistance (PTCR) was observed in the silver-doped barium titanate semiconductor. By the measurements of Seebeck effect and the apparent electric conductivity using various types of electrodes, it is found that the semiconduction behavior is essentially the same as that of rare-earth-doped barium titanate n-type semiconductor. The results of both the oxygen diffusion and the conductivity measurements suggested that the concentration of extrinsic oxygen vacancy is higher than that of intrinsic oxygen vacancy. It is concluded that the electric conduction may be due to the electrons excited from the oxygen vacancies, which were preferentially farmed at elevated temperatures. The amount of the vacancies decreases during slow cooling. Then the higher conductivity can be obtained by the rapid cooling down to the room temperature.

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Hydrodenitrogenation of pyrrole over various Poly (metal phthalocyanine) catalysts (Poly-MPc)was studied by a continuous flow system at the atmospheric pressure. The reaction products were ammonia, C₁C₄ hydrocarbons, and other nitrogen compounds. The yield of ammonia depended on the kind of central metal. The catalytic activity was found to decrease in the following order, Co >Pt> the other 8 metals (Mo, Fe, Ni, Mn, Zn, Cr, Pd, Cu). The mixedtype catalysts of Poly-Co-Fe-Pc, Poly-Co-Pt-Pc were more active for hydrodenitrogenation than the single type catalysts such as Poly-Co-Pc, Poly-Fe-Pc, or Poly-Pt-Pc. Insertion of two kinds of metal ions to the enlarged conjugated system of the catalysts gave a special effect on the yield of ammonia. The same effect was found on the mixed-type catalyst of PolyFe-Ni-Pc. The order of the reaction over Poly-Co-Pc catalyst was found to be 0.4 with respect to pyrrole, and 0.8 with respect to hydrogen. The activation energy observed was 15.9kcal/mol for this catalyst in the range of 450-525°C,

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The electrode reactions of deposition and dissolution of zinc were studied by the faradaic impedance method. The electrode reaction in aqueous zinc sulfate solution was controlled by the charge-transfer reaction (Zn²⁺ + 2e^- ⇔ Zn) accompanied by an adsorption process. In the solution of alkaline zincate, the diffusion of Zn(OH)₄^2- toward the interface from the ulk and dissolution of the zinc hydroxide film on the zinc electrode were the rate-determining step in the processes of cathodic deposition and anodic dissolution, respectively. The charge transfer resistance and the diffusion resistance of zincate ion were remarkably decreased. when the solution temperature reached to 50°C, but the rate-determining step was almost independent of the temperature. The charge-transfer step was determined when the overpotential was larger up to about 5-10 mV.

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The hydrous manganese(IV) oxide, which contained a large amount of alkali and chemically bound water, was prepared from a highly alkaline solution. Then, the hydrous manganese (IV) oxide suspended in aqueous potassium hydroxide solutions was electrolytically oxidized using a nickel anode at a constant current of 3.2 A/dm² without diaphragm. The electrolysis reaction, in the presence of a small amount of permanganate as an initiator for the oxidation reaction, is believed to take place in two simultaneous reactions, i. e. chemical oxidation and electrolytic oxidation given by:
MnO₂+2MnO₄^-+4OH=3MnO₄^2-+2H₂O, MnO₄^-=MnO₄^-+e
The current efficiency was found to increase with the increase of the amount of MnO₂, free KOH concentration and temperature. This effect is attributed to the fact that the chemical oxidation is the rate determining reaction. However, too much KOH, say more than 5 mol/l, resulted in the decomposition of permanganate into manganate(VI)
A typical set of conditions which realized a high current efficiency was: MnO₂; 0.65 mol/l, free KOH; 4.2 mol/l, temperature; 80°C. The effect of additives was also discussed.

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The ¹³C-NMR spectra for compounds containing a phosphorus and arsenic atom are reported. On the basis of the results obtained for diphenylalkylphosphines, the chemical shifts and coupling constants (Jp_0) of tertiary aliphatic phosphines are determined. A good linear relation is found between the carbon chemical shifts of the alkyl parts in the phosphines, arsines and their onium salts and those of the corresponding aliphatic hydrocarbons. The chemical shifts of a number of primary aliphatic phosphines have been investigated in hope of proving the information about α, β, γ, and δ effects of -PH₂ group.

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Chlorination of 2-halobutanes and chlorine addition to 2-butenes with CuCI, were investigated from the viewpoints of stereochemistry, regio-, and stereoselectivity. The reactions studied were mostly non-catalytic. But as for the chlorine addition, it was demonstrated that the reaction proceeded catalytically when CuC12-alkali chlorides were used as catalysts and HC1 and 02 as oxidizing reagents (Table 3).
At about 100°C, the main reactions of 2-halobutanes were acid-base reactions such as halogen exchange and dehydrohalogenation, which had been studied previously. At higher temperatures, halogenation and halogen addition became predominant (Fig.1). Chlorination was exclusively at carbon-3, and. dl or threo form was major product (Table 1). The chlorine addition proceeded almost completely by anti-addition (Table 2).
All of these results are rationally explained by a reaction scheme which assumes a halogenbridged cyclic intermediate. Of this intermediate the Z form is assumed to be more stable than the E form, owing to the repulsive interaction between the methyl groups and the surface (Fig.6).

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The reaction of a large quantity of phenol with isobutyl methyl ketone peroxide derived from isobutyl methyl ketone and hydrogen peroxide in situ has been studied kinetically in the presence of sulfuric acid as a catalyst. The reaction proceeds rapidly, and the rate is of first-order with respect to the concentrations of isobutyl methyl ketone and sulfuric acid, of second-order with respect to the concentration of hydrogen peroxide, and of inverse first-order with respect to the concentration of water. The apparent activation energy value for the reaction is obtained as 11.5 kcal/mol. The mechanism for formation of both catechol and hydroquinone by the reaction of phenol with the peroxide is discussed.

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Anthraquinone was found to react with an alkylamine in the presence of a rhodium( I)complex to give 1- (alkylamino anthraquinone ) along with a small amount of 1, 4-his (alkylamino)anthraquinoneC2 J. This direct amination occurred only at thecr-position of anthraquinone and gave a high selectivity for [1].
Though oxygen was necessary for the amination, it was found to be advisable to reflux the reaction mixture under nitrogen atmosphere, before the reaction was carried out in air (Table 1). Among the metal complexes examined under the reaction of anthraquinone with butylamine in diglyme, the dimeric complex, [RhCl(PPh₃)₂]₂, proved to be most effective. The result seems to show that the formation of a monomeric rhodium ( I ) complex, which is unsaturated in coordination, plays an important role in giving an active species for the amination. The yield of [1] based on the rhodium quantity was in excess of 100% when [RhCl(PPh₃)₂]₂was used as a catalyst, suggesting the efficient recycle of the rhodium ( I ) comlex. The highest yield of (I) was obtained at 120°C under the following conditions; the rhodium(I)complex 2.70 mmolg, an amine 2.6 mol/l and anthraquinone 51 mmolg. The yield was depressed by the oxidation of amine caused by rhodium( I ) complex (Tables 3 and 5). The electronic and steric effects of amines on the reaction were also examined (Table 4). When equi-gram rhodium in [RhCl(PPh₃)₂]₂ to anthraquinone was used, the yield of [1] reached to 40% in j9-picoline, contrary to the results in diglyme (Table 7).

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5-Nitro-, 5-amino-, 5-acetylamino-2, 3-dichloro-1, 4-naphthoquinones and 5-amino-, 5-acetylamino2, 3, 6, 8-tetrachloro-1, 4-naphthoquinones were condensed with aniline, panisidine and p-chloroaniline. The expected two isomers were isolated and their structures were determined by transformation to the known compounds. Effects of substituents at the benzenoid ring on the reactivity at the 2- and 3-positions have been studied by comparing the isomer ratios and electronic absorption spectra. The products provided an almost full spectral range of colors.

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The study was made to know the amount of gas occluded in Yabari Shin Daini coal and that evolved by its thermal decomposition as well as to elucidate: the evolution mech anism. Ab ove coal was heated at 100-283°C in vacuum and the rates of evolution of hydrog en, methane, and carbon monoxide were measured. The relation between the rate and the particle size was also examined. The amounts of these gases evolved on heating its pyridine extracts were measured as a function of heating temperature. It was concluded that: (1) The most of hydrogen, methane, and carbon monoxide occluded in it evolved at lower temperature than 150°C. (2) The temperature at which as evolution occurred in terms of thermal decomposition rose in the follo wing order: carbon monoxide<methane<hydrogen. In the case of hydrogen it was about 200°C. Occluded and th ermally produced hydrogen could clearly be distinguished, but the s ame was not true for methane. Above two kinds of carbon monoxide could not be distinguished. (3) The experimental rate of gas evolution was of the first-order with respect to the activation energy (Fig.5).

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A telomer containing pyridyl group (LVP) was obtained by solution polymerization of 4vinylpyridine using 1-dodecanethiol as a solvent and 2, 2'-azobisisobutyronitrile as an initiator. LV P was treated with benzyl chloride or ethyl bromide in methanol to give the corresponding telomer-type surfactants containing the partially-quaternized 4-vinylpyridine (LVP-BQ, LVP-EQ) (T ables 1, 2).
The catlytic activity of the CuLVP-BQ complex for the polymerization of xylenol (XOH)in water-benzene was higher than that of the partially-quaternized poly (4-vinylpyridine)(IVP-BQ) or pyridine. This may be ascribed to the adsorption of LVP-BQ at the waterbenzene interface and to the emulsification. The activity was affected by the molar ratio of 4-vinylpyridine unit to Cu (Fig.1), the solvent composition, the shaking rate of the vessel (Fi g.2), the nature of emulsifying agents (Fig.3), the polymerization degree of catalysts (Fig.4), the quaternizing agents and the quaternized percent. Linear relationships were observed between the polymerization rate of the 2, 6-disubstituted phenol and the logarithm of the rate constants of the electron-transfer step or Hammett's s values of 2, 6-disubstituted phenol (Fig.5). Therefore, the electron-transfer was considered to be rate -determining.

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Binding isotherms of 4-[bis (2-hydroxyethyl) amino]azobenzene (D- II ), Methyl, Ethyl and B utyl Orange (MO, EO and BO) to poly (vinylpyrrolidone) (PVP) have been determined in an acetate buffer solution at pH 5.65 and 25°C using a new dynamic dialysis cell (Fig.1) The cell was found to reproduce the literature values for the binding constant and the number of binding sites for MO-bovine serum albumin system. The binding isotherms for D- II, MO and EO -PVP are linear (Fig.4) or slightly convex downward (Fi g.5 and 7) with the intrinsic binding constants, (K) of 13.5, 25, and 35 l/residue mole, respectively. The binding isotherm for BO-PVP shows a sigrnoidal increase, indicating the cooperativity in the binding. The Scatchard plot for BO-PVP gives a convex upward curve (Fig.10). By applying McGhee and von Hippel's theory to the isotherm, the number of residues (n) covered by a bound BO, K, and the cooperativity parameter w were obtained as 11.5, 50l/residue mole, and 275, respectively.

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The polymerizations of methyl methacrylate initiated by low-molecular poly (vinylphosphonic acid) (PVP), low-molecular poly (sodium 3-hydroxypropyl phosphate) (PPP-Na), or high-molecular disodium salt of partially phosphorylated polystyrene (PStP-2 Na) were carried out in the aqueous solution at 85°C. To initiate the polymerization, PPP-Na required copper (II) ion while PVP and PStP-2 Na did not. The necessity of copper (II) ion for the polymerization was found to be dependent on the distance between the phosphoryl groups in the macromolecule. Since high-molecular macromolecules containing phosphoryl groups formed hydrophobic areas (HA) in the aqueous phase, the monomer was incorporated into the HA, and then the polymerization started in the HA, the polymerization took place easily. To the contrary, since low-molecular macromolecules did not form HA and then: the polymerization proceeded in water, the polymerization did not occur easily.

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The removal of oxygen from air was examined with a. carbonaceous adsorbent made from a Saran waste. The Saran waste was first decomposed and carbonized at 600°C. Then, adding 9.1 wt% of microcrystalline cellulose or sulfite pulp waste liquor as a pelletizing agent and 4.5-27.3 wt% of coal tar pitch as a binder of carbon, the Saran char was granulated into sphere using a disc-type pelletizer. Thus spherical particles obtained were heated at 850°C or 1000°C in the stream of nitrogen in an indirect-heated rotary kiln (Table 1). By the pressure swing adsorption with ca.200 g of these carbonaceous adsorbents, the oxygen concentration of the effluent gas could be controlled to 0.1-0.2% by volume. It was found that the concentration of oxygen decreased with the increase of adsorption pressure and the decrease of the flow rate of the effluent gas (Figs.3 and 5). The carbonaceous adsorbent prepared at 850°C from the mixture of 81.8 wt% of Saran char, 9.1 wt% of coal tar pitch and 9.1 wt% of the sulfite pulp waste liquor was found to be most suitable for the removal of oxygen from air (Table 2).

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Deodorization of sulfur compounds by catalytic oxidation was carried out by the use of a bench scale apparatus. Studies on kinetics of the reaction and catalytic actvities were made with platinum catalysts supported on γ-alumina in three forms granular Pt-Al₂O₃, honeycombshaped Pt-Al₂O₃ and aluminum tubular. Pt-Al₂O₃, at 170-350°. Thiophene, dimethyl sulfide, diethyl sulfide, or hydrogen sulfide (10 ppm) was used as a sulfur compound of low concentration. For a granular catalyst and a honeycomb-shaped catalyst, rates of thiophene oxidation were of the zero-order with respect to the thiophene concentration above 10 ppm and slightly positive order below 10 ppm. Diethyl sulfide concentration dependence of its oxidation on a honeycombshaped catalyst was similar to that of thiophene oxidation, while the rate of dimethyl sulfide oxidation was of about 1/2-order with respect to the dimethyl sulfide concentration in the range 10-400 ppm. Rates of hydrogen sulfide oxidation on a honeycomb-shaped catalyst and a aluminum tubular catalyst were of the first-order with to the hydrogen sulfide concentration. There was some differece of apparent activation energy of each reaction in the kind of catalyst. However, when comparing apparent activation energies of oxidation of four sulfur compounds, apparent activation energies of dimethyl sulfide and hydrogen sulfide were lower by several kcal/mol than those of thiophene and diethyl sulfide for respective catalyst. For respective catalyst in three forms, the activities of four kinds of sulfur compounds (10ppm) at 200°C was in the following order: (C₂H₅)₂S>thiophene≥(CH₃)₂>H₂S. On the basis of the above results, it was found that the above method was practically effective for the oxidative deodorization of thiophene and diethyl sulfide, but it was difficult to obtain high conversion for the oxidative deodorization of dimethyl sulfide and hydrogen sulfide at relatively low concentration and low temperature near 200°C.

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Chlorine in polychlorinated biphenyls (PCB's, KC-400) was almost completely removed by treating them with potassium graphite (C₈K) or sodium graphite (Cl₆Na) in THF at 0°C for 70 min the amount of residual organic chlorine in former and latter cases was less than O.05and 0.002 wt%, respectively. The minimum amount of C₈K necessary to remove all chlorine in PCB's was estimated to be ca.3 mol/Cl, being the same in two dropping methods (normal methodPCB's were added to the reductant; inverse method----the reductant was added to PCB's). The rate of dechlorination found by means of these treatments was slower than that found in terms of naphthalenides. The average molecular weights of the dechlorinated products were relatively high (230-270), which decreased (167-194) in the presence of proton source: in this case biphenyl (154) became the major product. The present method seemed to be useful for a facile decomposition of PCB's as well as an easy recovery of graphite.

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Nitrate ion in water is easily reduced with Cr(II)-hedta (HEDTA =H₃hedta: N'-(2-hydroxyethyl)ethylenediamine-N, N, N'-triacetic acid) complex by the following reaction,
6 Cr(II)-hedta + NO₃^- + 8 H⁺ 6 Cr(III)-hedta NH₃OH⁺ + 2 H₂O
and so, nitrate ion can be reduced electrolytically in the presence of Cr(III)-hedta as a catalyst. In this investigation, the amount of nitrate ion was determined by measuring the quantity of electricity flowed during electrolysis, using electrolytic cell shown in Fig.1. The procedure of electrolysis is as follows; a chrome alum solution and an acetate buffer solution of pH 5 containing glycine and Cu²⁺ ion are added to the sample solution, and the electrolysis is carried out for a short time to reduce substances such as oxygen. After this pre-electrolysis, hedta solution is added to form Cr (III)-hedta complex and electrolysis is continued (Fig.2).
Calibration curve shown in Fig.3 is linear up to 30μmol NO₃^- (0.28-8.4 mg/l as NO₃^--N)and the slope agrees with the value calculated from the assumption that 6 electrons are associated in the reduction of nitrate ion. The effect of diverse substances was shown in Tables 2, 3 and 4. Many organic substances and inorganic ions had little influence, except for AsO₂^-. NH₄⁺ did not interfere and the interference by NO₂^- was negligible up to 5 mg/l. Nitrate ion concentrations in river water and sewage plant effluent were determined by this method. They were in good agreement with the values determined by devarda's alloy method (Table 5). Comparing with other methods, the advantages of this method in the determination of nitrate ion in water is discussed in detail.

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A new hybrid thermochemical hydrogen production process, Sb-Br hybrid process, is presented together with relevant preliminary experimental data. The process consists of the following three steps.
1/2Sb₂O₃(s)+Br₂(l)+H₂O(l)Lowt temp./1/2Sb₂O₃(s)+2HBr(aq)(1)
2HBr(aq)Electrolysis H₂(g)+Br₂(l)(2)
1/2 Sb₂O₅(s) high temp. 1/2 Sb₂O₈(s) + 1/2 O₂(g)(3)
The main reaction (1) was completed in about 2 h at 303 K to produce a 32 wt% HBr solution at optimum conditions. Reactions (2) and (3) already verified make the Sb-Br hybrid process feasible. A flow sheet estimation showed that the overall efficiency of this process, η_LRVwas 35-40%. when heat recovery was 70-80%.

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The pure Na₅P₃O₁₀, (phase I ) free from orthophosphatea s well as other polyphosphatews as preparedb y the followingp rocedure. Twenty gram of Na₃P₃O₉, prepared by heating NaH₂PO₄ at 530°C, was dissolved in 200 cm³ of water and 25 cm³ of 6 mol dm^-3 NaOH aqueous solution was added. After the solution was allowedt o stand at room temperaturef or 72---9h6, equalvolume of ethanol was added to produce the precipitate, which was separated by Biichner funnel, and washed with (1: 1) mixture of ethanol and water and finally with ethanol. The precipitatew as dried in air to obtain the Na₅P₃O₁₀·6H₂O, which changed to anhydrous form by heating at 550°C.

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A study on the metal-substitution reaction of metalloporphyrin complexes has been done I. f rom the viewpoint of acceleration of the complex formation of porphyrins with metal ions in aqueous solution. Cadmium (II), mercury (II) and lead (II) complexes of anionic porphyrins such as α, β, γ, δ-tetrakis (4-sulfophenyl) porphine andα, β, γ, δtetrakis (4-carboxyphenyl) porphine were found to be metal-substituted almost instantaneously by copper(II), zinc(II), cobalt (II)or manganese(II) even at room temperature in aqueous alkaline solution. However, the metal-substitution of their complexes of cationic porphyrins such as α, β, γ, δ-tetrakis (1-methylpyridinium3-yl)porphine and α, β, γ, δ-tetrakis(1-methylpyridiniurn-4-yl)porphine by the metal ions above was not so fast as expected. On the basis of this finding, a possible rapid spectrophotometric determination of copper, zinc, cobalt and manganese at ppb levels with the anionic porphyrins as color-producing reagents was suggested.

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The metal contamination of silicon surface during the acid etching process of silicon diodes equipped with electrodes has been studied by ion microanalyzer(IMA). Silicon diode devices consist of silicon pellets soldered by aluminium, tungsten electrodes and copper lead wires. Both aluminium and copper become dissolved in HF-HNO₃, etchant. The analysis by IMA indicated that copper only deposited on the silicon surface and selectively on the n⁺ layer at the junction. Potentials in the HF-HNO₃ etchant were measured on constituent materials in devices. Copper had a higher potential than silicon and the n⁺ layer indicated the lowest potential in the silicon surface of diode. It is concluded that copper in the etchants deposits selectively on the n⁺ layer having the lowest potential in the silicon surface.

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Conformations of 4-alkyl- and 4-alkoxycyclohexanecarboxylic acid isomers with relatively long and linear carbon chains have been examined by ¹³C-NMR. The alkyl (butyl) derivative obtained from the corresponding benzoic acid by PtO₂, hydrogenation consists of a mixture of two configurations, trans-form and cis-form (Fig.1). Both had alkyl-equatorial conformations. Th e alkoxy (butoxy, pentyloxy, hexyloxy) products obtained by catalytic reduction over PdC contain a mixture of two forms (Fig.2). However, the cis-alkoxy compound has a different conformation from the cis-alkyl compound; the alkoxyl group is exclusively in the axial orientation.

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In the presence of pyridine and triethylamine, m- and p-substituted anilines were allowed to react with an excess of benzoyl chloride in refluxing chloroform to give the corresponding N, N-dibenzoylated derivatives in appreciable yields. To investigate the substituent effect on the reaction, the benzoylation of the respective N-arylbenzamides was followed by high pressure liquid chromatography. As a result, it was clarified that the electron-attractive substituents accelerate the benzoylation of N-arylbenzamides, contrary to the known monobenzoylation of substituted anilines. The reaction mechanism was discussed.

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New polyamideimides containing a bicyclo[2.2.2]octene ring in their main chains were synthesized by the method of low temperature solution polymerization of various diamines with N, N'-bis[p- (chlorof ormyl) phenyl] bicyclo [2.2.2] oct-7-ene-2, 3; 5, 6-bis (dicarboximide) [1]. The thermal stabilities as well as solubilities of the polymers obtained were investigated. Inherent viscosities of these polymers are 0.24-0.43g·dl^-1 (in 0.5 gg·dl^-1 DMF solution, at 25± 0.01°C). Most of these polymers are soluble in such an organic solvent as DMF, DMA, DMSO or mcresol. On the basis of the thermal analyses, it was found that all these polymers decompose at 360-400°C in air. However, the thermal stabilities of polymers obtained from [1] and aromatic diamines are superior to those obtained from [1] and aliphatic diamines

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A study was made on the determination: of sulfuric acid aerosol in an atmosphere. A sulfuric acid aerosol and air-borne particulate matter in an atmosphere were captured on a teflon filter. A teflon filter was placed in a glass-stoppered test. tube and 2-propanol was added to it to extract sulfuric acid aerosol. The 2-propanol extract was centrifuged. A 7 mi of supernatant solution was put into a glass-stoppered test tube and 2.7 ml of water and O.3 ml of buffer solution (pH 5.6) were added to it. After addition of 50 mg of powdered barium chloranilate to it, the test tube was shaken and then allowed to stand. After filtration, the absorbance of the filtrate at a wavelength of 330 nm was measured. It was found that the detection limit of this method was 2 μg/m³ when air was sampled during 50 min at a rate of 20 1 per min. The method was applied to a practical determination of sulfuric acid aerosol in air at Setagaya, Tokyo. As a sesult, it was found that the concentration of sulfuric acid aerosol was 2-11μg/m³ and the proportion of sulfates was 10-53%. The concentration of sulfuric acid aerosol increased with increasing photochemical smog in summer.

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