A new perovskite-type compound, (Pb_1-x Na_yx-y) (Zr_0.3Ti_0.7)O_8-x+y/2, was prepared by the solid-solid reaction of a mixture (1-x) PbO+(x/2) Na₂ CO₃+(Zr_0.2, Ti_0.7)O₂, where (Zr, Ti)O₂ was obtained by drying the co-precipitate from a mixed solution of Ti⁴⁺ and Zr⁴⁺ with aqueous ammonia. Firing at about 800°C for 1 hr was most suitable for the preparation of the monophasic perovskite. Above 1000°C, ZrO₂ was more or less isolated from the host. When a simple mixture of PbO, Na₂CO₂, ZrO₂ and TiO₂ was used, the formtion of lead titanate besides the host perovskite was always observed. The chemical formula, (Pb_1-x Na_yx-y) (Zr_0.3Ti_0.7)O_8-x+y/x was confirmed by comparing the calculated density with the observed one and by the analyses of X-ray diffraction intensities. No hysterisis loop was detected by use of the Sawyer Tower circuit, probably because the coersive field is too high, as is in the case for PbTiOs. The temperature dependence of permittivity clearly showed anomaly, which suggests the materials to be ferroelectric. The permittivity anomaly extended over a wide range of temperature. This phenomenon was interpreted in terms of an inhomogeneous distribution of A-site ions in these materials.

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It was foudd that palladium (II) chloride is a highly active catalyst for the synthesis of alkali formate from carbon dioxide and hydrogen in an aqueous alkali solution under pressure. For example, potassium formate, in 82.6 mol% yield, was obtained under the following condition: pressure of carbon dioxide being 40 atm, pressure of hydrogen being 106 atm, concentration of palladium(II) chloride being 1.0 g/l, concentration of potassim hydroxide in aqueous solution being 1.9 mol/l, temperature being 240deg;C, and period of reaction being 3 hrs.
The effect of following variables on the rate of formation of formate was examined in view of kinetics: starting amount of catalyst, alkali concentration, partial pressure of carbon dioxide or hydrogen, and temperature. Assuming that the reaction substances involved hydrogencarbonate ion and active catalyst-hydrogen complexes, following initial rate equation has been derived:: Solubility constant of 112, Pressure of H₂, M: Palladium-catalyst, V0: Initial rate. This equation reasonably agreed with experimental results.
The values of the apparent rate constant k', the equilibrium constant Ks, and the overall activation energy Ea, were found to be 2.90×10^-2(160deg;C) 4.97×10^-2 la g-cat^-2min^-1(200°C), 28.4 (160°C) 13.2 ismol-i (200°C), and 7 kcal. mol^-1 respectively.

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The phosphidation kinetics of powdered chromium has been studied under gaseous phosphorus atmosphere of 100-760 mmHg in a closed vessel at 600-700°C. As a sinter of phosphides formed, a-alumina powder was previously added to the chromium sample as a diluent at a weight ratio (Cr/Al₂O₃) of 2.
The reaction products were CrP and Cr₃P as a result of X-ray diffraction analysis, and CrP₂, a higher phosphide, was not found. In an earlier stage of the phosphidation the reaction proceeded linearly with time and, subsequently, parabolically. In an earlier stage, the ratedetermining step seemed to be a surface reaction; therefore the study was made by applying the Langmuir adsorption isotherm. As its result, it could be presumed that the phosphidation proceeded under the adsorption-dissociation of gaseous P₄, molecule into four phosphorus atoms. On the other hand, in an advanced stage of the phosphidation, the data showing the relation between the fractional phosphidation and time fitted approximately Jander's equation under the present reaction condition. Hence, the rate-determining step seemed to be a diffusion process.
It could be concluded that the rate-determining step of the phosphidation of chromium transferred from the surface reaction to the diffusion process.

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Effects of K₂CO₃ on the decomposition of butane, and on the reaction of butane with steam, over supported nickel catalysts at 400-500°C were studied.
Addition of K₂CO₃ to the catalysts brought about no effect on the degree of butane decomposition. The composition of carbon deposit, CH_0.2 on the average, at 460°C, obtained by the reaction over the catalysts containing K₂CO₃, did not differ from that without K₂CO₃. On the other hand, in the reaction of butane with steam the activity of the catalysts not containing K₂CO₃ decreased with time. When K₂CO₃ was added, the lapsing decay of catalysts was improved, despite the stationary activity decreased.
These experimental results were explained in terms of the reaction mechanism that butane and water were adsorbed on a nickel surface competitively, and then the reaction occurred between these adsorbed species. It was concluded that when water was absent or the amount of water on the surface was not sufficient, the adsorbed butane might decompose to form carbon deposit.

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Vapor-phase oxidative dehydrogenation of isobutylaldehyde over various B403 catalysts promoted with alkali metal oxides or alkaline earth metal oxides has been investigated to the reaction mechanism of methacrylaldehyde formation and the effect of addition of these oxides on the catalytic activity of Bi₂O₃. Almost selective formation of methacrylaldehyde was observed during the reaction of isobutylaldehyde with these promoted Bi₂O₃ in the absence of gaseous oxygen; the Bi₂O₃ containing these oxides at 10-15 atm% was most effective for methacryl- aldehyde formation. Furthermore, the conversion of isobutylaldehyde and the yield of methacrylaldehyde at zero reaction time increased with the decrease in the electronegativity of metal ion added to Bi₂O₃. Similar regularity was also observed in the catalytic oxidative dehydrogenation of isobutylaldehyde and the catalytic oxidation of carbon monoxide over these oxides. In the catalytic oxidative dehydrogenation over Cs₂0-Bi₂O₃ (Cs=15 atm %), the yield of methacryl- aldehyde was 47.1%, the selectivity being 65.5% at 450°C. Formations of carbon dioxide and of methacrylaldehyde were kinetically discussed on the basis of the regularity observed, and participation of lattice oxygen rather than oxygen species adsorbed in the oxidative dehydrogenation was proposed. Metal oxides added probably control the strength of Bi-O bond according to the electronegativities of metal ions.

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Monoclinic CePO₄ was formed by aging hexagonal CePO₄ in the aqueous solution, whose pH range being 1-12, at above 50°C (Fig.2). The rate of formation of monoclinic CePO₄ became high with decreasing pH and with increasing temperature. Hexagonal CePO₄ gradually dis- appea'red as the aging progressed. For the formation of monoclinic CePO₄ by aging hexagonal CePO₄, about 90 days were necessary to keep it in the solution, whose pH being 1, and about 900 days in it, whose pH being 12, at 50°C. Monoclinic CePO₄ crystals showed similar columnar shape as the starting hexagonal CePO₄ (Fig.5). At 20°C, hexagonal CePO₄ dissolved in the solution, whose pH being 1, after aging it for about 180 days, but it was stable in the solution, whose pH being above 2, after aging it for about 900 days.329

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Cadmium sulfide was obtained as precipitate from an aqueous solution of cadmium salt by adding sodium thiosulfate homogeneously. Aging of the precipitate at 95°C for five hours gave rise to reddish orange colored spherical particles of cadmium sulfide with the diameter between 5 to 15 μm. The grain size was decreased down to 2 pm by addition of ethanol during the precipitation reaction with the change in color into bright yellow. The spherical shape was kept up to 550°C in a nitrogen stream.

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Complicated thermogravimetric curve was observed on oxidation process of cadmium sulfide precipitate in air. Phases of various oxidation stage were identified by X-ray diffraction method. Cadmium sulfide was first oxidized to cadmium oxide at 400°C, while the successive reaction with sulfur dioxide and oxygen gases gave rise to cadmium sulfate. The phases such as 2CdS, CdSO₄, Cd₃SO₆ and β-CdSO₄ appeared during the oxidation process up to 1100°C, at which all the particles were converted into cadmium oxide at 1100°C. Cadmium sulfide kept in nitrogen gas above 700°C was directly converted into cadmium oxide when oxygen as was introduced into the furnace.

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Study on the growth of CaWO₄ (Scheelite) needle crystals by chemically reacted flux method was made by means of slow cooling of CaWO₄ from KCl fluxed melt.
A mixture of CaClex H₂O, WON, K₂CO₃, and KCl was heated in a platinum crucible in an electric furnace at a temperature of 1000 or 1150°C for 10 hours and then gradually cooled to 700°C at a cooling rate of 5°C/hr. CaWO₄ could be produced as follows: CaCl₂, H₂O + WO₈ + K₂C0₈ + y KCl → CaWO₄ + (2+y) KCl +xH₂O↑ + CO₂↑
During cooling CaWO₄ crystals have been formed.
Results obtained are as follows: (1) On cooling from a temperature of the liquid consisting of CaWO₄-KCl, whose region being shown in the phase diagram, CaWO₄ needle crystals were formed. (2) The needle crystal, having maximum length of about 2 mm, could be formed. The needle crystals had a silky luster and their surfaces were smooth. The growth direction of the needle crystal was considered to be <001> or <110>. (3) The maximum growth rate of needle crystal was about 16 × 10^-3 p/sec on the basis of suitable assumptions.

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Chemiluminescence, occurred in the reactions of various substances with atomic oxygen, was used to detect gaseous compounds sensitively. Atomic oxygen was produced by dissociating molecular oxygen in terms of a microwave discharge, and chemiluminescence was detected by photomultiplier. To measure 'intensity distribution of chemiluminescence, interference filters were used. Chemiluminescence from nitrogen compounds distributed from 400 nm to infrared, and that from sulfur compounds from 200 nm to 500 nm. And maximum intensity of chemilminescence of nitrogen or sulfur compound was at 610 nm or 300 nm, respectively. Therefore, selective detections of nitrogen and sulfur compounds could be possible (Fig.8). Detection limits of several substances were compared (Table 1). Chemiluminescent intensity changed linearly with concentration from several ppm to.1000 ppm. Detection limits of. NO_x and H₂S were 5 ppb and 20 ppb, respectively.

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Semimethylxylenol Blue (SMXB) reacts with thorium to form a water-soluble reddish-violet complex and its aqueous solution has an absorption maximum at 559-564 nm. The coloration is stable over the pH range from 2.9 to 3.4 and obeys Beer's law up to 2.2 sag/mi of thorium. The molar extinction coefficient of the complex and the sensitivity of the determination are 5.97× 10⁴ and 0.0039 pg Th/cm² for log (I₀/I) =0.001, respectively. The composition of the complex was determined as Th (SMXB), by mole ratio and by continuous variation methods. Among the thirty-eight diverse ions examined, aluminum, gallium, arsenic (V), bismuth (III), scandium, yttrium, zirconium, vanadium(V), molybdenum(VI), iron (III), phosphate, fluoride and oxalate interfere with the determination. But aluminum can be masked by the addition of sulfosalicylic acid and the effect of iron (III) is eliminated with ascorbic acid. The interference from bismuth (III) can be removed by a filtration of the precipitate of bismuth chloride oxide. The standard procedure for the determination is as follows.
A sample solution containing up to 55 pg of thorium is taken into a 25 ml volumetric flask and the pH is adjusted to 3.0 by adding 5 ml of buffer solution. Then, 3 ml of O.05% SMXB solution is added and the volume is made to 25 ml with water. The absorbance is measured at 562 nm against the reagent blank as a reference.

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The dependence of the stabilities of 4-substituted derivatives of pyridinium cation and 1, 4- dilaydrc, -4-pyridyl radical on their substituent groups, their charge densities and hyperfine splitting constants of 4-substituted dihydro pyridyl radicals were investigated by using the INDO method. and the following results were obtained, (1) As to 4-substituted pyridinium cations, an electron donating group makes the cation more stable than an electron attracting group. On the other hand, the stability of a 4-substituted dihydro pyridyl radical depends on the electron attracting character of the substituent group. An electron attracting group makes the dihydro pyridyl radical more stable than an electron donating group. (2) The stabilization energies zIET of 4-substituted derivatives of pyridinium cation can be correlated with the Hammett constants for the substituted groups. (3) The unpaired electron orbital energy of a dihydro pyridyl radical with an electron donating group is higher than that of the radical with an electron attracting group, the former being more unstable than the latter. (4) The substituent groups have a small effect on the calculated hyperfine coupling constants of the parent part of 4-substituted dihydropyridyl radicals.

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The title reactions have been studied in relation to elucidation of the functions of the biotinyl prosthetic group in enzymatic carboxylations promoted by biotin-enzymes. The patterns of the title reactions depend strongly upon the nature of substituents on the imidazolidinone ring and the structure of nucleophiles employed. In the reaction with butylamine, the following patterns were disclosed. (1) For 1-methoxycarbonyl-2-imidazolidinone E1 a 1 the reaction leading to the open-chain product C_2C a J predominates; the reaction takes place at the carbonyl carbon in the imidazolidinone ring (U mode attack). (2) For 1- cetyl-2-imidazolidinone 14 d D, two types of reactions, namely the U mode attack and the nucleophilic attack at the acetyl carbonyl carbon, take place simultaneously. (3) For 3-substituted 1-methoxycarbonyl-2-imidazolidinones substituents; C61-15, COOCH₃, COCH, the U mode attack is no longer observed. The attack at the carbonyl carbon of the substituents at the 1- and 3-positions predominates instead. (4) The U mode attack is observable only when the 2-imidazolidinone ring bears electronwithdrawing substituents such as acetyl and methoxycarbonyl groups at the 1- or 3-position. (5) For 1-methoxycarbonyl-cis-perhydrocyclopenta [d] imidazol-2-one C7 a 1 the attack at the carbonyl carbon of the 1-methoxycarbonyl group predominates, in contrast to the reaction of 1 a D. (6) The U mode attack occurs through an isocyanatte intermediate. On the other hand, in the case of the reactions of Cl a and its derivatives with sodium benzenethiolate, the attack at the methyl carbon of the methoxycarbonyl group occurs perferentially to other modes of the reactions. These results are discussed in terms of the structural features of substituents and also of the reaction mechanisms.

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During the reaction of 1-butene catalyzed by W03-Si02, a small amounts of volatile compounds were injected into the reactor. The products were analyzed by gas chromatography, and the effects of addition of the compounds on the disproportionation and isomerization of 1-butene were evaluated. Hydrogen chloride, chloroform, carbon tetrachloride, certain brominated cornpounds, butylamine, and isobutylamine promote the disproportionation and inhibit the isomerization. Water, ethanol, diethyl ether, ethylene glycol, 1-fluorohexane, and diethyl sulfide promote the isomerization and inhibit the disproportionation. Carboxylic acids, their derivatives, nitro- methane, piperidine, and certain halogenated compounds inhibit the disproportionation and isomerization. Compounds, capable of promoting the above both reactions, were not found. The compounds, capable of promoting the disproportionation by pulse addition, were added continuously to the reactor; the continuous addition mostly showed similar results as above, but some of them showed different results. From these experimental results, it is suggested that the catalyst of an unstable state, formed by the interaction of W03-SiO₂ catalyst and a halogenated compound, is very active for the disproportionation but the halogenated compound itself rather interfere with the reaction.

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apor-phase reaction of cyclopentadiene with ethylene over silicon carbide has been investi-gated at atmospheric pressure in relation with the reaction mechanism. The reaction was always accompanied with a formation of carbonaceous deposit over silicon carbide, and at 300 400-C, only 2-norbornene was formed whereas selective formation of an equimolar mixture of 1- and 2-ethylcyclopentadiene was observed above 500-C. When 0.10 atm of cyclopentadieneand 0.40 atm of ethylene were feeded at a contact time of 93. 3 g-SiC*r/g-mol at 570°, the yield and the selectivity of ethylcyclopentadiene were 5.4% and 48.3%, respectively. These results suggest that ethylcyclopentadiene was produced by the isomerization of 2-norbornene or by the hydrogen transfer of biradical compound, which were formed by the addition of ethylene to cyclopentadiene. On the other hand, exchange of deuterium atoms for hydrogen atoms of cyclopentadiene molecule was observed in the reaction of cyclopentadiene with deuterium gas over the carbonaceaus deposit at 570-C.The carbonaceous material was thus found to partici-pate in the hydrogen transfer. The rate constants for addition of various unsaturated hydro-carbons to cyclopentadiene were kinetically determined, and the order of the constant was ethylene<acetylene<butadiene. On the basis of this result, mechanism of the addition of these unsaturated hydrocarbOns to cyclopentadiene was discussed.

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7, 15-Dihydropyrido[2, 1-b]pyrido[1', 2': 1, 2]pyrimido[4, 5-g]quinazoline--7, 15-dione [ 2] was efficiently prepared by the dehydrogenation of 6, 7, 14, 15-tetrahydropyrido[2, 1-b]pyrido[1', 2': 1, 2]pyrimido[4, 5-g]quinazoline-7, 15-dione [ 4], which was derived from diethyl 2, 5-dioxocyclohexane-1, 4-dicarboxylate and 2-aminopyridine, with a nitro compound in the presence of alkali. The reaction is considered to be accompanied by the hydrolysis to give 2, 5-bis (2- pyridylamino)terephthalic acid [5] followed by cyclization. p-Benzoquinone also dehydrogenated [4] to give [2] directly under acidic conditions. The reaction of chloranil with [ 4 ] afforded the molecular complex of [ 2 ] with tetrachloro-p-hydro- quinone, from which [ 2 ] was extracted with conc. FI2SO₄. Some pigment properties of [2], such as color, the resistance to light, heat, acid, alkali, and organic solvents were also examined in comparison with those of quinacridone and/or cadmium red. From these results, it is concluded that the pigment is quite similar to cadmium red in color and has excellent pigment properties as a substitute for cadmium red. t Studies on Quinazoline Pigments. I.

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By employing the aqueous potassium dichromate solution, whose Cr 00 concentration being 10 ppm, the adsorption of Cr (V) on activated carbon has been studied. The following conclusions were obtained by investigating the adsorption of Cr (VI) and Cr 110 as a function of pH and by determining the amount of total Cr and Cr (VI) eluted from activated carbon with either NaOH or HCI solution. In the pH range from 4 to 6.5, Cr (1, ) is readily adsorbed on activated carbon in the form of anionic species such as HCr04- and Cr042- (Fig.1, 2 and 5), while Cr" ion is scarcely adsorbed on activated carbon (Fig.4). In acidic solution, Cr (VI) is easily reduced to Cr OE in the presence of activated carbon (Fig.5). Adsorbed Cr() on activated carbon was eluted quantitatively in the form of Cr (171) by using NaOH solution, whose concentration being higher than 0.1 N, while 90% of it was eluted in the form of Cr (111) by using 1 N HCl solution (Table 2).

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p-Aminobenzoic acid (PABA) reacts with triose reductone (TR) to form two yellow condensates, consisting of rnonoanil and dianil whose molar ratio of TR to PABA, being 1: 1 and 1: 2, respectively, and whose absorption maxima in dimethyl sulfoxide (DMSO), being 365 nm and 430 nm, again respectively. The amount of TR was determined by the absorbance at the maximum absorption value ADD: N°=430 nm and el'allg= 7.0 x 1O^2-. When 2.0 to 12 pg of TR was allowed to react with 3.0 ml of 1 N-HCl solution contaning 0.1 moli/ PABA, only dianil was formed. This is the specific reaction of PABA toward TR among various reductones. On the basis of these results, the procedures for the determination of TR were recomended as follows: The solution (1.0 ml), containing 2.0 to 12 pg of TR was added to the solution (3.0 ml of 1N HCl) containing 0.1 molf/ PABA at 20°C and 5.0 ml of DMSO was added to the reaction mixture after 30 min. The solution was diluted to 10 ml with H₂0 and its absorbance was mesured at 430 nm against the blank. Several substances such as L-ascorbic acid, reductic acid, sugers, other organic acids, aldehydes, and metal ions except for Cu", Fe", Mn²⁺, and Hg²⁺ did not interfere with the determination of TR.

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The correlations between the stabilities of 7, 7, 8, 8-tetracyanoquinodimethane (CQ) salts of polycation polymers and their electric conductivities were studied to elucidate the decomposition reaction of CQ salts. The specific resistance (P) of polycation-CQ salts changed as follows in an air: p: CQ simple salt>CQ complex salt Solution>Solid state. The results of electronic spectra showed that the stabilities of CQ salts related to the decomposition of CQ anion radical (CQ') and to that due to water. On the basis of the chemical analyses of the isolated decomposition products, CQ was found to change into ce, a'-dicyano-p(cyanocarbony1)-a-toluenide (DCT-). As a result of the decomposition of CQ, the electric conductivities of polycation-CQ salts decreased not only with losing unpaired electrons, carrier of electricity, but also with disintegrating conduction paths.

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The role of a certain base or copper (II) salt in the condensation polymerization of 2, 4, 6- tribromophenol catalyzed by the DMF-CuCl2 complex was studied. In the reaction at a room temperature, the polymer yield, aftet reaching a maximum within 10 minutes, remained constant. However, the melecular weight of the polymer increased with progressing time even after several hours. The molecular weight also increased with repeating polymerization reactions, which occurred to the product of the initial reaction. These results suggest the occurrence of the head-to-tail polymerization. From the study on the mechanism of the polymerization, a certain base did not take part in the mutual interaction between it and copper (II) salt, but interacted with the monomer to promote the dissociation and to release HBr from it. The catalytic activity of copper 10 salt was found to depend on the Taft's substituent constant of anionic group which combined with copper (II) ion.

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Copolymerization of styrene with 3-m"ethy1-3-buten-2-one was studied in the presence of zinc chloride. Zinc chloride easily coordinates with 3-methyl-3-buten-2-one and its double bond stretchings and n-x* absorption shift toward lower energy side.By the addition of styrene to the coordinated compound, the binary complex ([MIPKSt]) and the ternary complex ([ZnCl₂MIPK₂St₂]) are formed. The ternary complex is C-T complex. Formation constants of the binary and the ternary complexs are 0.16 and about 0.21 at 25°C in chloroform, respectively. AIBN initiated copolymerization of styrene with 3-methy1-3-buten-2-one in the presence of: zinc chloride brings about styrene-3-methyl-3-buten-2-one 1: 1 copolymer and polystyrene. The alternating tendency of copolymer composition increases with increasing amount of initial zinc chloride and styrene., Yields of copolymer and polystyrene increase with increasing concentration of the ternary coMplex. The copolymer is 1: 1 alternating copolymer' on the basis of the composition curve of this system and the measurement of NMR spectrum of polymer itself. These results showed that this polymerization is the homopolymerization of the ternary complex and a part of ionic dissociation of the ternary complex brings about the cationic polymerization of styrene.

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The reaction of fibrous cotton cellulose with o- or p-nitrophenyl carbanilates (o- or p-NPCA) or o- or p-chlorophenyl carbanilates (o- or p-CPCA), as isocyanate generator9, has been studied in order to obtain cellulose carbanilates of high nitrogen contents. In the case of the reaction of cellulose with o-NPCA, the product of the highest nitrogen content (7.66%) was obtained from the reaction mixture of Cotton linter, pyridine, and o-NPCA in wt. ratio 1.00: 58.9 14.4(3 times of the amount required for tricarbanilation), respectively, at 120°C for 15 hr under nitrogen atmosphere. The highest nitrogen content of the product obtained by the reaction of cellulose with o-CPCA was 7.0^2-% under the reaction conditions of Cotton linter, pyridine, and o-CPCA in wt. ratio 1.00: 58.9 13.7(3 times of the amount required for tricarbanilation), respectively, at 120°C for 10 hr. The ortho isomer was more reactive than the para isomer in both NPCA and CPCA. This may be due to the fact that orth isomer generates isocyanate more easily than para isomer in both NPCA and CPCA. The X-ray diffraction study of the cellulose carbanilates showed that the reactions of cotton cellulose with isocyanate generating substances were heterogeneous which proceeded from amorphous to crystalline region in cellulose fiber.

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The catalytic liquid-phase hydrogenation of a-metylstyrene to give cumene over Pd/Al2O^2-catalyst suspended in a bubble column has been studied to evaluate the resistances to the mass transfer.
The mass transfer resistance at gas-liquid interface (1/kLab) can be evaluated independently, but the mass transfer resistance at liquid-solid interface (lIksas) must be separated. from the overall resistance on the basis of the hydrogen concentration at catalyst surface which is related to that at gas-liquid interface with the ratio of chemical reaction rate to overall rate. Thus liksas can be evaluated individually using the values of 1/kLab and chemical reaction rate previously estimated when chemical reaction is rate-controlling in stirred vessel with hydrogen bubbling.
The correlations between 1/kLas, liksas or contribution of individual resistance to overall resistance and operating variables such as gas flow rate and catalyst loading were obtained as shown in Figs.4, 5 and 6.
In addition, correlations of gas hold up, bubble diameter, gas-liquid interfacial area and mass transfer coefficients with operating variables were obtained as shown in Figs.7, 8, 9 and 10.

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A new method was developed for the generation of sulfur dioxide with constant low concentration (from 10 to 0.01 ppm). This method is based on the generation of sulfur dioxide from an aqueous solution of sodium hydrogensulfite with appropriate buffer agents. The pH of the solution was controlled by adding the buffer agents to it. Sulfur dioxide was generated by passing air through the surface of the solution. The generated gas was diluted with air of constant stream, passed through a purification bed. The concentration of the gas depended on pH, concentration, and temperature of the sodium hydrogensulfite solution. The gas generation from the solution began at pH 7.0, and generation of a large amount of gas occurred at pH 4. O. A logarithmic relationship between concentration of the solution and that of the generated gas in the air stream was found in a concentration range of sodium hydrogensulfite solution from 5 X 10 to 5x 1O^2- pglml. The temperature dependence on this method was much less than that on the permeation tube method and the variation of concentration of the generated gas with temperature was 0.O^2- ppm/°C at 20, ---30°C, 0.56 ppm of SOO. The concentration of the generated gas reached a constant value within about 40 min after starting of the air flow, and it remained constant at least during 6 hours. The range of variation of the generated gas was 2% at 0.56 ppm.

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Studies of certain higher calcium dicarboxylates, (CH₂)_n(C00)₂Ca (n=4, 6, 8, 9, 10, 11, 12), were made by using the methods of TGA and DTA. These higher salts exhibited different melting behavior from that of lower calcium dicarboxylates, which decomposed thermally without melting. The melting points decreased with increasing n of methylene units in alkyl chains. The melting behavior was irreversible and the resulted melts were amorphous and exhibited a polymer-like property. The glass transition temperatures of the melts varied zigzag with increasing methylene units similarly as in the case of melting points of corresponding acids.

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The hydrothermal oxidizing of chromite was suggested as the possible new wet metallurgical method of chromium. One gram of chromite sample and 5 ml of solvent was added into the micro-autoclave (12 ml of inner volume) with ball for stirring and induced 100 kg/cm' of 02 gas and then was heated in a revolving furnace at temperatures between 150 to 350°C. Cr (VI) ion in the eluted yellow solution was determined by colorimetric analysis. The extractio ratio of Cr(VI) ion from chromite was 70% under conditions of 350°C, 50 minutes. But at above this temperature, higher extraction ratio of Cr(VI) ion from chromite is expected. Besides, the chromite slag containing Cr(VI) ion of few percents was reduced perfectly under hydrothermal condition, at 350°C, for 80 minutes. And then, it was expected that the hydro- thermal process is appliciable as the harmless wet metallurgy of chromite.

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Oxidation of 3-nitro-o-xylene with air in alcoholic alkaline solution was studied. Main reaction product was assumed to be 2, 2'-dimethyl-6, 6'-dinitrobibenzyl (MNB). MNB was obtained in high yield under following conditions: system; EtOH-KOH, amount of KOH; 8-10 fold of 3-nitro-o-xylene, reaction temperature; 2030°C, reaction time; 6 hours, flow rate. of air; 122 m/imin.

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The Central Resarch Institute of Mitsubishi Electric Corporation; Amagasaki-shi 661 Japan The structure and motional state of chlorophyllin-poly (adenylic acid) complex were studied. Cu-chlorophyllin (Cu-chin) showed remarkable paramagnetic effects on proton relaxation rates of poly (adenylic acid) (Poly A). The longitudinal relaxation rates (T1-1) of the Cu-chln Poly A complex were measured. On the basis of these results, the apparent distance between the electron spin of copper and each proton of Poly A were calculated by the equation of copper and each proton of Poly A were calculated by the equation of Bloembergen, Purcell and Pound (H 8; 7.4A, H 2; 8.9A, H 1'; 12. OA). By comparing the above data with those of Cu-chinMP complex (H 8; 7.5A, H 2; 7.7A, H 1'; 8.211. ), the structure of Cu-chin Poly A complex was discussed. By comparing the temperatures at the minimum of T1B, it was found that H 8 or H 2 had slower motional speed in the presence of Cu-chin than in the absence of it.

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An effectiveness of a number of combinations of aprotic dipolar solvents and catalysts was examined for the synthesis of polyroxy (2, 6-dibromo-1, 4-phenylene) (POBP) from 2, 4, 6- tribromophenol. The polymer was obtained in high yields in solvents such as DMSO, DMA, arid DMF; however, the yield was poor in HMPA or CH, CN. The catalysts for the polymeriztion of 2, 6-xylenol, except for iron salts, were also found effective for the synthesis of POBP. Copp

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