The coercivity of a nonstoichiometric iron oxide (Fe²⁺/Fe³⁺=0. 11) increased when the iron oxide was treated with sodium triphosphate, Na₅P₃O₁₀, at an elevated temperature as in the treatment of sodium metaphosphate, which was already reported. The increase of the coercivity depend on the temperature of the treatment and molar ratio of sodium triphosphate to the iron oxide. The maximum of the coercivity was obtained approximately at 120°C and two certain molar ratios.
The cercivity increased in this treatment changed with time on standing as follows. The coercivity obtained in the treatment at 100°C tend to converge to a constant value after irregular changes. However, when the iron oxide was treated at temperatures between 150°C and 300°C, the coercivity was also found to increase with time.
The behavior of the hydrous sodium triphosphate (B), obtained by drying the aqueous solution of sodium triphosphate at room temperature, was studied to investigate the reason for the increase of the coercivity. The (B) was found to be mainly composed of Na₅P₃O₁₀. 6H₂O. Its composition unchanged when thermally treated at 120°C, but when it was treated at 150°C, the phase of Na₅P₃O₁₀.6H₂O disappeared and a small amount of sodium pyrophosphate, Na₄P₂O₇, was found. No increase of the coercivity of the iron oxide was observed by treatment with sodium pyrophosphate. The (B) treated at 300°C transformed to anhydrous sodium triphosphate.
The experiments showed that the increase of the coercivity depended on Na₅P₃O₁₀ and the water of crystallization in the hydrous sodium triphosphate did not affect the increase of the coercivity.

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The homogeneous catalytic hydrogenation of cyclopentadiene (CPD) to cyclopentene (CPE) with bis(dimethylglyoximato)pyridinecobalt(II) (pyridinecobaloxime) was carried out in several solvents at 50°C under atmospheric hydrogen pressure. Under these conditions, CPE could be obtained in a high selectivity (ca. 100%) even at 100% conversion.
Kinetic data in methanol are consistent with the hydrogenation mechanism expressed by Scheme 1. Each constant in Scheme 1 was calculated as follows : K₁'=1. 49 K₂=15. 55 l.mol^-1, K₁=6. 41 l.mol^-1, and K₂'=0. 33. It was found that a large excess of CPD reduces the hydrogenation rate by the formation of the π-complex with pyridinecobaloxime. For such cases, the rate-determining step is shifted from Eq. (3) to Eq. (2), the hydrogen absorption process. Additional deuterium tracer studies showed that this hydrogenation is proceeded by 1, 4-addition of hydrogen to CPD.

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Oxidation of styrene to styrene oxide and to carbon dioxide over several silver catalysts has been investigated in comparison with that of ethylene by use of pulse technique. Carbon dioxide was formed when air was injected over the catalyst which had been treated with a pulse containing styrene and air. Therefore, the residue responsible for the combustion must be adsorbed in a considerable amount on the catalyst in the continuous flow reaction system. It was shown that the smaller the amounts of adsorbed residues were on the catalysts, the higher the activities in the continuous flow reaction were (Table 1). On the other hand, in the case of the oxidation of ethylene, the amount of the adsorbed residue was very small on the catalyst. This difference in the amount of the residue is the reason why there is no apparent relation between the activity for the oxidation of styrene and that for ethylene. When styrene oxide was injected over the reduced catalyst, styrene and carbon dioxide produced (Fig. 3). The reported reaction of ethylene oxide is similar to that of styrene oxide ; the formation of ethylene and carbon dioxide. Styrene conversion fell to almost zero within 30 sec after air pulse (Fig. 5). Similar phenomena were observed for ethylene (Fig. 6). When styrene was injected over the oxidized catalyst, the reactivity of styrene during the reduction of silver oxide varied similarly to that of ethylene (Fig. 7). These findings suggest that the oxygen species on the surface available for styrene oxidation is the same as that for ethylene.

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The glass fibers of A and E types were coated with a tin oxide film by the contact with dimethyltin dichloride (CH₃)₂SnCl₂ at high temperatures during the spinning of the fibers from the glass melt.
Several properties of the fibers were improved by the coating : 14 percent increase in tensile strength for the fibers of 12 μm in diameter, and 48 and 35 percent increases in water and 0. 1 N hydrochloric acid resistances of the fiber of A type coated at 80°C for 24 hours, respectively.

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Single crystals of black phosphorus were grown by the solidification from the melt under high temperatures from 840 to 1760°C and high pressures from 4 to 10 kbar for the duration times from 3 to 10 min. A piston-cylinder type high pressure apparatus was used. Red phosphorus powder with about 5 μm in size was placed as a starting material in a carbon tube heater of 6. 2 mm in diameter and 20 mm long.
Stability of phosphorus obtained in the present work was as follows. Red phosphorus was stable below 700°C at 6 kbar and 500°C at 10 kbar. The powdered black phosphorus was grown in the temperature range from 720 to 900°C at 6 kbar and 550 to 1000°C at 10 kbar, by poly-morphic transformation from red phosphorus (about 5 μm in sise) occuring in the solid state. The liquid phase region was found in the temperature range from 900 to 1400°C at 6 kbar and 1050 to 1600°C at 10 kbar. On the otheer hand, the vapor phase region was found above 1500°C at 6 kbar, 1700°C at 10 kbar and above 700°C at 3 kbar.
The single crystal of black phosphorus grown had maximum dimensions of about 4. 5 × 2.0 × 0. 23 mm, with a characteristic metal lustre and a shape well developed along the ‹100› direction. Surface microstructures of single crystals of black phosphorus were studied by optical microscopy. Growth hills on the plane normal to the c-axis were found to exhibit round shape, which were about 3. 5 μm in maximum diameter and about 1 μm on the average. From the results of X-ray method, the single crystals of black phosphorus were found to have high crystallinity.

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Needle crystals of MgWO₄ were grown by cooling the high-temperature solution of MgW04 KCl mixture and crystal length was studied by means of photomicroscope. The MgWO₄KCl solution was heated to 900 or 1000°C for 5 hours and gradually cooled to about 500°C at a rate of 5°C/hr.
Results obtained were as follows ;
(1) Needle crystals of MgWO₄ were grown from the fluxed melt having the solute concentration from 1 to 15 mol% (soaking temperature 900°C) or from 2. 5 to 15 mol% (soaking temperature 1000°C).
(2) Needle crystal with the length of 5.7 mm and the diameter of 20 μ could be grown. The growth direction of the needle crystal was considered to be <100>. The needle crystals whose form was tetragonal prism had a silky luster and smooth surface.
(3) The relation between the length of needle crystal and solute concentration approximately followed Weimarn's theory.

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Xenotime (tetragonal YPO₄) was synthesized by the precipitation from a mixed solution of yttrium chloride and orthophosphoric acid or orthophosphate above 50°C. At 50°C, the initial precipitate from the solutions in the pH range from 0. 8 to 2. 9 was - crystalline weinschenkite (monoclinic YPO₄. 2H₂O) and amorphous phosphate was formed at pH above 3, while preci-pitation did not take place at pH 0. 5., Weinschenkite was stable at 50°C, but amorphous phosphate gradually crystallized by aging and became crystalline xenotime at pH 3. 7 after 5 days and at pH 5. 0 after 28 days. At 90°C, xenotime was detected in the precipitate from the solution of pH 0. 5, and was also obtained by aging weinschenkite at pH between 0. 8 and 2. 9 or amorphous phosphate at pH above 3. Theunit cell parameters of the synthesized xenotime were as follows : a=b=6.893Å, c=6. 6.026Å.

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The polarographic behavior of the cadmium (II) in the presence of triethylenetetraminehexa acetic acid (H₆ttha=TTHA) was studied over the pH range 3∼6. The mechanism of the electrode processes was elucidated and the electrochemical kinetic parameters were evaluated from the dependence of the half-wave potentials on the hydrogen ion and TTHA concentra-tions. Three different polarographic waves can be distinguished. In the presence of an excess of cadmium (II), amperometric titrations showed that the reaction mechanism for the first wave (W₂) could be expressed by the following scheme :
Cd₂L^2-+H⁺ Cd₂HL^- Cd²⁺+CdHL^3- (fast)
Cd²⁺+2e+Hg → Cd(Hg)
The waves (W₂) occuring at the negative potential are assigned to the irreversible reductions of CdH₂L^2- (pH range 3.55-5.0) and CdHL^2- (pH range 5.2∼6.1) in the presence of excess TTHA.
The electrode reaction can be written
CdH₂L^2-+H⁺ + 2e Cd(Hg) +H₃L^3-
and
CdHL^3-+H⁺+2e+Hg Cd(Hg)+H₂L^4-
where k_e (the rate constant)=3.7 × 10^-3cm/s and k_e'=1.6 × 10^-5 cm/s.
The kinetic wave (W₁) occuring at a concentration ratio [Cd]_t /[TTHA]_t of 1 to 1 may be ascribable to the reduction of Cd²⁺formed by the slow dissociation of the Cd(II)-ttha complex CdH₂L^2- :
CdH₂L^2- Cd²⁺ + H₂L^4-
The rate constant of the dissociation, k_d, was 3.2 × 10³s^-1.

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The presence of complex ion species, such as EuL^3-, EuHL^2- and EuH₂L^-, was presumed. The stability constants of the europium (III)-TTHA complexes weredetermined by the application of Martell's method of approach for the potentiometric titration curves, and log K_Eu(III)L=23. 28, logK_Eu(III)HL=16. 56, and log K_Eu(III)H2L=10. 22 were obtained. In the presence of an anion of TTHA(H₃L^3-, H₄L^2-), europium (III) is reversibly reduced to europium(II) at the dropping mercury electrode in the pH range from 3. 55 to 6. 1. By the analysis of the dependence of half-wave potential on the hydrogen ion concentration, it is concluded that Eu(III)-TTHA complex is not dissociated, and europium(III) is reduced in the pH range 5. 2∼6. 1 by the following electrode reaction :
Eu(III)L³⁺+H⁺+e Eu(II)HL^3-
The stability constant of Eu(II)-TTHA complex calculated from the equation (6) gave logK_Eu(III)HL=9. 26.
E_1/2=E=⁰ -0.0591 log (K_Eu(III)L/K_Eu(III)HL) +0.0591 pk₁ - 0.0591 pH (6)
In the pH range 4.10∼ 5.0, the following electrode reaction is also proposed.
Eu(III)L³⁺+3H+e Eu(II)H₃L^3-
Eu(II)(OAc)₃ Eu(II)H_tL
The analysis of the dependence of limiting current on the hydrogen ion and TTHA ligand concentrations showed that they had no effect on fimitirtg current over x wide pH range.

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The complex was formed between lanthanoid(III) ion and triethylenetetraminehexaacetic acid (TTHA). Stability constants (K_LnL) were determined polarographically by the use of Schwarzenbach's method with cadmium as an indicator ion in a sodium acetate-acetic acid buffer solution (0. 4 mol/l).
The scheme of the exchange reaction between cadmium(II)-TTHA complex and lanthanoid, (III) ion is expressed as follows:
CdHL^3- Ln³⁺ Cd²⁺ LnL^3- +H⁺
Cd2L^2- Ln(OAc)_n^3-n Cd _m^2-m
The evaluation of K_LnL is based on the following equation.
log K_LnL=log K+logK_CdHL+pk₁-pH
=log K +22. 17
The stability constants of the lanthanoid complexes (log K_LnL) obtained for Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb were respectively 22. 83, 23. 45, 23. 68, 23. 81, 23. 85, 23. 83, 23. 61, 23. 29, 23. 58, 23. 62, 23. 58. The stability constant increased regularly with increasing atomic number of the lanthanoid ion up to europium, while beyond europium it decreased irregularly. The stability constant for polyamine-N-polycarboxylate complex increased in the sequence of the ligand.
hedta < edta < tpha < dtpa < ttha

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Phenylfluorone reacts with nickel in the presence of hexaclecyltrimethylammonium bromide and pyridine to form a blue water-soluble chelate. The absorption maximum was found at 620 nm and its absorbance was constant in the pH region 8.50∼10.0. The molar absorptivity is 1. 04×10⁵ at 620 nm and the sensitivity is 0.000565 μg Ni/cm² for log (I₀/I)=0, 001. The complex formation was applied to the determination of a micro amount of nickel.
The calibration curve prepared at 620 nm was linear for the nickel concentration up to 5. 6 × 10^-6 mol/l. The composition ratio of nickel to phenylfluorone in the complex was estimated to be 1 to 2 in the presence of both hexadecyltrimethylammonium bromide and pyridine.
The recommended procedure is as follows : To a 25 tnl volumetric flask add the sample solution containing less than 8. 25 μg of nickel. Then add 2.5 ml buffer solution, 1. 5 ml oif 2× 10^-2 molg hexadecyltrimethylammonium bromide solution, 2, 5 ml of 2.48 mol/l pyridine solution and 2. 5 ml of 1 × 10^-4mol/l phenylfluorone solution to the sample sollition. Dilute the solution to the mark with distilled water. After it is allowed to stand for 15:miriutes at 25°C, measure the absorbance at 620 nm against the reagent blank.

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A new highly sensitive method for spectrophotometric determination of small amounts of cadmium (II) has been developed. Water-soluble porphyrin, α, β, γ, δ-tetraphenylporphinetri-sulfonic acid (TPPS) reacted with cadmium (II) ion to form a green complex in a pH range 10 to 13. 5. The complexation was very slow at room temperature, however, it was accele-rated by addition of 2 × 10^-4 to 10^-8 mol/l of 2, 2'-bipyridyl to the reaction system and was completed within 4 min (Fig. 4). The Soret band of the complex is located at a wavelength of 432 nm (ε=4. 45 × 10⁵), which is well apart from that of free TPPS (413 nm, ε=5. 1 × 10⁵) (Fig. 1). Many metal ions interfered with the determination of cadmium (Table 1). Cadmium (II) was selectively separated from these ions, except In³⁺ and Hg²⁺, by the extraction with HBr-KBr-trioctylamine-xylene systems as a bromo complex, followed by the back-extraction with 1 mol/l aqueous sodium perchlorate solution. Then, Cd²⁺ can be selectively determined by the following procedure : put a sample solution containing 1∼5 μg of Cd²⁺ into a 50 ml beaker and add 2 ml of 1 × 10^-2 mol/l 2, 2'-bipyridyl solution and 1 ml of 1 × 10^-4 TPPS solution. Transfer the mixture to a 50 ml amber-volumetric flask, add 2 ml of 1 mol/l sodium hydroxide solution and dilute to the mark with water. After standing for 5 min, measure the absorbance at 432 nm against water.
Beer's law was confirmed over a concentration range of 4°100 ng Cd²⁺/m/ and the sensiti-vity for absorbance 0. 001 was 0. 26 ng Cd²⁺/cm², which is about five times as sensitive as that of the dithizone method. The coefficient of variation was 2. 14% for 56. 2 ng Cd²⁺/ml (10 deter-minations) . Tolerance limits for Hg²⁺ and In³⁺ were 100 μg/50 ml (with thiourea as a masking agent) and 5 μg/50 ml, respectively (Table 2). Satisfactory recovery of Cd²⁺ (99. 4%. c. v.=1. 66%, 5 determinations) was obtained for the samples prepared by adding 5. 6 ng of Cd²⁺ to 1 ml of river water.

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Sodium sulfate in detergents was determined by high speed liquid chromatography on a porous micro-spherical strong anion exchanger (TSK-Gel LS-222) column with 0.1 mol/l nitric acid-56times;10^-3 mol/l iron(III) nitrate as an eluent. Iron(III) is very effective as the eluting agent since it forms the complexes with sulfate, pyrophosphate, and triphosphate in detergents. It also serves as a color-developing agent for sulfate ions in the column efflue, nt. The capacity factor of sulfate decreased with increasing iron(III) nitrate concentration in the eluent, but the peak area of sulfate obtained from the chromatogrin increased, as shown in Fig. 1.
Anionic surface-active agents, were strongly held by the anion- exchanger and those of sulfate ester type were not hydrolyzed in the eluent. Inorganic and organic builders such as condensed phosphates and citrate were not sorbed to any significant extent on the column. By the postcolumn method described previously, pyrophosphate, sulfate, and triphosphate were eluted in that order as shown in Fig. 2. The distribntion coefficient of pyrophosphate decreased remarkably in the presence of iron (III) in the eluent, because pyrophosphate forms a stable iron (III) pyrophosphate complex and was not sorbed by the anion exchanger as predicted by Eqs. 6, 7, and 8. Iron (III) and triphosphate also react to form the stable complex as is the case for iron (III) pyrophosphate complex. Ingredients in detergents did not interfere with the analysis. The calibration curve was linear over a range of 40∼420 mg/100 ml (Fig. 3). Analysis of a standard solution and a standard detergent yielded satisfactory results (Tables 1 and 2). Sodium sulfate in several commercial detergents was determined by the proposed method without any interference and the results agreed with those of conventional chelatometry, as shown in Table 3.

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The relationship between absorption intensity of resonant γ-ray of iron-57 (14.41 keV) and amounts of iron(III) hydroxide [Fe(OH)₃], Goethite (α-FeOOH) and Hematite (α-Fe₂O₃) was investigated aiming at establishing the quantitative chemical analysis by means of Mössbauer spectrometry. The linear relation was found between them in the iron concentration range from 0 to 8 mg/cm² as in Fig. 2. By utilizing the analytical curve, transformation rate of amorphous Fe(OH)₃ through the aging in aqueous solution was studied at various pH and temperature of the solution. Fe(OH)₃ undergoes the transformation to antiferromagnetic α-FeOOH at pH higher than 9, when the temperature of solution is 348 K. The transformation rate proceeds most rapid in the solution of pH 13. The transformation is seriously disturbed in the concentration above pH 13. Antiferromagnetic α-FeOOH and α-Fe₂O₃ were not formed within a few hours above pH 13. Mechanism of the transformation was also discussed.

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A minute amount of cadmium can be determined by the isotope dilution method with surface emission mass spectrometry using ¹¹⁶Cd as a spike. After extracted into 15 ml of 0.00125% dithizone chloroform solution from the sample spiked with ¹¹⁶Cd, cadmium is back extracted into 5 ml of 7 N nitric acid. The nitric acid solution is treated with 0.1 ml of 60% perchloric acid and dried up in a heated pyrex glass oven supplied with a high purity nitrogen gas. The residue is dissolved in a mixture of 60 μl of 0.003% silica gel suspended water and 5 μl of 2% phosphoric acid. An aliquot of the dissolved solution is loaded onto the center of a rhenium single filament in a surface ionization device of the mass spectrometer. The present method can determine the ratio of ¹¹⁴Cd/¹¹⁶Cd with the precision from 0.4 to 1.1% in coefficient of variation, where the detection limit for Cd⁺ ion is 10^-14∼10^-18 g. The application of the present method to orchard leaves delivered by National Bureau of Standards, U. S. A., as a standard reference material in environments has proved its superior usefulness by giving results in close agreement with those certified by N. B. S.

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The conformations of phthalaldehyde, isophthalaldehyde and terephthalaldehyde were investigated by the CNDO/2, EHMO, and P-P-P SCF-MO-Cl methods. The total energies of the seven planar models for phthalaldehyde and p, m-isomers were calculated by the CNDO/2 and EHMO methods, and the dipole moments of the models were calculated by the CNDO/2 method. The calculated values of dipole moment were compared with the corresponding experimental ones.
The total energy of terephthalaldehyde with a formyl group twisted out of the molecular plane was calculated to elucidate the most stable conformation by the CNDO/2 and EHMO methods. The CNDO/2 method showed that the conformation with the formyl group twisted at an angle of 90° was the most stable, but the EHMO method gave opposite result and indicated that a potential barrier height of about 2 kcal/mol existed near 90° for the s-cis-s-trans isomerization of terephthalaldehyde. The latter result looks reasonable more than the former one, because it is difficult to accept that terephthalaldehyde has two types of formyl groups, one of them is coplanar to the benzene ring but the other is perpendicular to the molecular plane.
The EHMO method showed that there was a potential barrier height of about 4. 6 kcal/mol for isophthalaldehyde isomerization. These results suggest that the planar conformation is energetically stable for tere- and isophthalaldehydes.
The same method was applied in the calculation of the total energy of the twisted phthalaldehyde to elucidate any stable conformation. Its stable conformation was confirmed to be the structure with the two formyl groups twisted out of the molecular plane.
The π-π transition energies and their oscillator strengths of the above phthalaldehyde models were calculated by the P-P-P SCF-MO-Cl method. The calculated spectroscopic values were compared with the observed UV spectral data to check whether the models obtained by the CNDO/2 and EHMO methods are favorable or not.

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Catalytic hydrogenation and chemical reduction of 2- and 3-substituted 1-indanones were carried out, and the steric configuration and the proportion of the products were determined. In the catalytic hydrogenation of 2-methyl-1-indanone [1], the cis-alcohol [5] was preferably formed irrespective of the catalysts, whereas in the case of metal hydride complex or Meerwein-Ponndorf reduction, [1] afforded trans-alcohol [6] as a main product. The hydrogenation of 2-phenyl-1-indanone [2] gave predominantly the cis-alcohol [8] with Raney-Ni or Pt catalyst, but over Pd catalyst the trans-alcohol [9] was formed more than the cis-alcohol. When [2] was reduced with lithium aluminum hydride, trans-alcohol [9] was produced as a main product, whereas in the case of sodium borohydride or lithium tri-t-butoxyaluminum hydride reduction, cis-alcohol [8] was obtained predominantly. In the case of chemical reduction or catalytic hydrogenation, 3-methyl-[3] and 3-phenyl-1-indanone [4] gave the cis-alcohol in high yield.
On the basis of the above results, the stereochemistry concerning the reduction of 1-inda-nones was discussed. In the catalytic hydrogenation, it was considered that the reaction proceeds via a π-benzylic type half-hydrogenated state and that the predominant production of the trans-alcohol in the hydrogenation of [2] catalyzed by Pd is attributed to the bulkiness of the phenyl group.

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We have previously reported that propyleneimine (PI) reacts with carbon dioxide (CO₂) to give a polyurethane without catalyst, and that both 4-methyl-2-oxazolidone (MOZ) and homopolymer of propyleneimine are obtained in the presence of a Lewis acid.
This parer describes closely the reaction of propyleneimine with CO₂ in the presence of Lewis acids and solvents. When iodine as catalyst and acetone or dichloromethane as solvent were used, the best result was obtained. On the basis of the kinetic study of the reaction in terms of NMR spectroscopy, the following rate equations were obtained.
R(MOZ)=k[CO₂]₀[I₂]₀[PI]₀²
R(Polymer)=k¹[I₂]₀[PI]₀²
A reasonable mechanism was proposed on the basis of these results and those obtained, by the visible spectra of the reacting substances. The reaction of CO₂ with ethyleneim ine was also investigated briefly.

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Nucleophilic reactions of two isomers [(CF₃)₂CF]₂C=CFCF₃(T-2) and (CF₃)₂CF(CF₃CF₂)C=C(CF₃)₂(T-3) of hexafluoropropene trimers with phenols were investigated. When phenol was allowed to react with T-2 or T-3 in the presence of triethylamine, a substitution product [(CF₃)₂CF]₂C=C(OPh)CF₃[2], (Fig. 1) was solely obtained from either trimer. It was experimentally ascertained that the highly reactive T-2 was preferentially attacked by phenol to give [2], whereas T-3 reacted with phenol after being isomerized to T-2 by triethylamine (Fig. 2).
When sodium phenoxide was used, T-3 reacted rapidly as well to produce a diether [6] (Fig. 3). On the other hand, the monoether [2] and sodium phenoxide gave an acetal [4], though this compound was thermodynamically unstable.

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The reaction of three isomeric iodoanisoles with an excess of 80∼96% sulfuric acid at temperatures 20∼100°C has been investigated by the H NMR analysis of the sulfonation products. Both o- and p-iodoanisoles, [1] and [2], readily underwent disproportionation, giving 2, 4-diiodoanisole [4] and a mixture of four sulfonic acids, anisole-2- and 4-sulfonic acids, [5] and [6], 4-iodoanisole-2-sulfonic acid [7], and 2-iodoanisole-4-sulfonic acid [8].
With increasing temperatures, the relative yields of [4] and [6] decreased in favor of [8], while the relative yield of [7] did not change significantly (Table 2 and 3). Iodoanisoles recovered from the reaction mixture was found to consist both of [1] and [2], the latter being predominant. Interconversion between [1] and [2] occurred slowly even in 80% sulfuric acid at 20∼60°C, but under these conditions no disproportionation took place and the yields of [7] and [8] were quite small.
m-Iodoanisole [3] was readily sulfonated to give a mixture of 5-iodoanisole-2-sulfonic acid [9] and 3-iodoanisole-4-sulfonic acid [10], neither disproportionation nor isomerization being observed to occur.
A mechanistic analogy to the Reverdin rearrangement has been suggested for the sulfonation of [2] to [8].

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N-Substituted 2, 2-diphenyl- or 2-cyano-2-phenylthioacetamide was dimetallated by butyllithium in tetrahydrofuran, while it was monometallated by ethylmagnesium bromide. The dilithio-diphenylthioacetamides were decomposed in 2 hr at refluxing temperature to give the corresponding ketenimines in 27∼43% yields, although the mono (bromomagnesio) thioamides were not decomposed. The decomposition reaction was accelerated by the addition of carbon disulfide or sulfur dioxide to afford the ketenimines in higher yields (45∼88%) for 15∼30 min at 0°C and inorganic salt, Li₂CS₃(or Li₂S₂O₂'), was precipitated. If lithium trithiocarbonate precipitated was not separated from the reaction mixture, the reverse reaction occurred to give the starting thioamide in an almost quantitative yield. At higher reaction temperature (∼60°C), the dilithio thioamides were decomposed in the presence of excess carbon disulfide to give isothiocyanates. On the other hand, dilithio-2-cyano-2-phenylthioacetamides reacted with carbon disulfide or sulfur dioxide even at 0°C to afford isothiocyanates.
Diphenylmethane was carbonimidoylated by an one-flask method to give ketenimines (45∼69%), using butyllithium, isothiocyanates, and carbon disulfide.

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Azo dyes [1]∼[4] fade in aqueous solution on irradiation with the light of the wavelength shorter than 300 nm. A fluorescent brightener of pyrazoline type (F_wo) accelerates the photofading of the dyes in the presence of the dissolved oxygen (Fig. 3). The acceleration is particularly marked with the wavelengths corresponding to the excitation maximum of the fluorescent brightener. On the other hand the dyes quench the photoreaction of the fluorescent brightener. The paper-chromatographic analyses of the photoproducts (Fig. 6) and the sensitization studies with biacetyl reveal that the fluorescent brightener sensitizes the inherent photoreactions of the dyes through the triplet energy transfer.

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The Friedel-Crafts reaction of 3-phenyl-6-dimethylaminophthalides [1] with anilines or indoles has been studied. For example, the reaction of 3-(4-dimethylaminophenyl)-6-dime-thylaminophthalide [1a] with N, N-dimethylaniline in the presence of anhydrous aluminum chloride in 1, 1, 2, 2-tetrachloroethane at 50°C for 5 hrs gave 4, 4', 4"-tris(dimethylamino)triphenylmethane-2-carboxylic acid [2a] in a quantative yield. The structure of [2a] was identified by comparison with the authentic sample prepared by the reaction of Michler's hydrol with m-dimethylaminobenzoic acid.
Similarly, the similar reaction of other substituted phthalides [1] with anilines or indoles gave triarylmethane derivatives [2] in good yields.
Furthermore, the oxidation of these triarylmethane derivatives [2] was carried out to prepare some new 3, 3-diaryl-6-dimethylaminophthalides [3] useful as color formers in pressure sensitive copying papers. The structure of these products were determined by means of spectroscopy and/or by comarison with authentic samples.
A mechanism for the reaction of [1a] with N, N-dimethylaniline was discussed.

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Hydrogenolysis of stereoisomeric 1-bromo-1-fluoro-2-phenylcyclopropanes [1a] and [1b] over PdO catalyst has been investigated in methanol as a solvent under ordinary conditions. Both [1a] and [1b] gave the same product mixtures. In the early stage of the hydrogenation, propylbenzene [2], 2-fluoro-3-phenylpropene [3], 2-fluoro-1-phenylpropane [4] and (Z)-2-fluoro-1-phenylpropene [5] were formed. Products [2] and [4] increased with the progress of hydrogenation, whereas [3] and [5] decreased gradually (Fig. 1 and 2). Independent hydrogenation of [3] gave [2] and [4] accompanied partially with isomerization to [5]. Product [5] was hydrogenated to 2 and [4]. Although the sites of fluorine atoms in [3], [4] and [5] show that the fission of cyclopropane ring occurs at C₂-C₃ bond, 2-bromo-2-fluoro-1-phenylpropane [6] was not detected in the hydrogenolysis of [1a] and [1b]. From these results [3] seems to be a main precursor of [2], [4] and [5], and may be formed by β-trans-elimination of the bromide ion or the bromine atom by electron transfer from C₃-carbon-metal bond in the adsorbed species [C].

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Ozonolysis of d-longifolene [1], camphene [9], 8-pinene [17] and 1, 7, 7-trimethy1-2-methylenenorbornane [22] has been carefully examined. On ozonolysis of [1] and [22], abnormal oxidation products were obtained as the principal products. However, oxonolysis of [9] and [17] afforded mainly the corresponding ketones and the Baeyer-Villiger type oxidation products. These results indiacte that the steric hindrance caused by the bulky group at the C-7 position of these bicycloalkane systems is an important factor leading to the abnormal ozonolysis.

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Homopolymerization and copolymerization of allyl glycidyl phthalate (AGP) and allyl glycidyl hexahydrophthalate (AGH) were carried out with benzoyl peroxide (BPO) and bis (1-methyl-1-phenylethyl) peroxide (DCPO) as initiators in bulk. The orders of initiator concentration for the homopolymerization were estimated as 0.73, 0.84, 0.59 and 0.62 for combinations AGP-BPO at 70°C, AGH-BPO at 70°C, AGP-DCPO at 110°C and AGH-DCPO at 110°C, respectively. The overall activation energies for homopolymerization initiated by BPO were found to be 26.6 kcal/mol (AGP) and 26.1 kcal/mol (AGH).
All the homopolymers obtained by the radical initiation were semisolids and exhibited molecular weights in the range 5400∼7000. They contained the practically unchanged epoxy ring as a pendant group.
The monomer reactivity ratios for the copolymerization of AGP and AGH with styrene were obtained as :
AGP (M₁)-Styrene(M₂) ;r₁=0. 136 ±0.009, r₂=34.8 ±1. 0
AGH (M₁) -Styrene (M₁) ; r₁=0.060 ±0. 009, r₂=34. 3 ± 1.3
The chain-transfer constants of the styryl radical to ally! glycidyl esters were determined by graphically solving the Mayo's equation, as C₃. 2.21 × 10^-3 and 3.03 × 10^-3 for AGP and AGH, respectively. These values are quite large compared to the known C₃ values of diallyl esters.

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In order to elucidate the thermal degradation mechanism of polystyrene, the influence of preheating on the degradation products was investigated in a flow system of fixed bed reactor under atmospheric pressure and at 400°C.
The preheating of the polymer was carried out in the range from 250°C to 310°C for 1∼5 hr in a stream of nitrogen.
The yield of styrene decreased and that of wax-like compounds, consisting of tetramerdecamer, increased with lengthening time of preheating and rising temperature (Table 2 and Fig. 2). This tendency was ascribed to the decrease in initial average molecular weight and the formation of wax-like compounds which is thermally stable during preheating period. The thermally stable structures were considered to form by the re-combination of secondary radicals or phenyl radicals (Schcme 8∼13).
The thermal degradation of polystyrene was confirmed to proceed not only in terms of conventional degradation-volatilization process, but also in terms of the formation of wax-like compounds having thernially-table structures.

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The thermal conversion of poly (amic acid) to polyimide in solid state accompanies considerable change in physical or mechanical property. It is necessary to elucidate these changes, in order to obtain the end products having prominent properties.
The change in dimension, weight, density, or dynamic mechanical property of film of a poly (amic acid), which was prepared from 4, 4'-diaminodiphenyl ether and pyromellitic dianhydride, upon imidation has been investigated. The degrees of imidation at various temperatures were estimated on the basis of the relative intensity of an imide absorption peak (725cm^-1) in the infrared spectra of the films. On the basis of the inared analyses, it was found that imidation began at 120°C and was completed at 240°C.
Upon imidation, the unstretched films shrank by ca. 10% on original length, whereas the grctched films on the contrary, lengthened by ca. 2%. The weight loss after termination of imidation was about 11% on the original weight, which was larger than the theoretical value (8.82%) of weight loss calculated on the basis of the change in structual formula. The excess of weight loss seemed to be due to the removal of adsorbed solvent. The density of the film rapidly increased from 1.381 to 1.400g/cm³ upon imidation. The temperature ranges, in which the change in dimension, weight, or density occurred, were approximately in agreement with those determined by the infrared analyses. On the other hand, the dynamic mechanical properties changed tpon imidation in more complex ways and in lower temperature ranges than the physical properties described above.

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Isotherms and rates of oxidation adsorption of NO on 3 kinds of activated carbon in N₂, O₂+N₂ or O₂+ H₂O+N₂ atmosphere as well as the adsorbed species were investigated as a basic study for the removal of nitrogen oxides from exhaust gas. The temperatures were chosen at 75°C and 100°C, and the concentration ranges of NO, H₂O and O₂ were 100∼5000 ppm, 1.4∼30% (relative humidity :3. 6∼79%) and 0. 25∼20%, respectively.
Adsorption of NO is virtually nil in the absence of 02. In 02+N2, NO is seemed to be adsorbed as NO₂ on the activated carbon. The adsorption isotherms are expressed by the Freundlich equation and depend considerably on the concentrations of N and O₂ (Fig. 1∼3). The adsorption rate is controlled by the rate of the oxidation reaction on the surface of carbon. The rate is expressed by the equation : Q_t/Q_∞=1 - exp (-kC C_t), (Fig. 4, 5) .
In O₂ -I- H₂O N₂, NO is adsorbed as nitric acid on the carbon. The content of HNO₃ is determined by the relative humidity in the same way as in the case of NO₂ adsorption reported in one of our previous papers (Fig. 6) . The adsorption isotherms depend slightly on the concentrations of NO and O₂, and the amounts adsorbed are much more than those in O₂ + N₂ at the low concentration of NO (Fig. 7∼9). The adsorption rate is affected by the rates of both the intraparticle diffusion and oxidation reaction on the surface of carbon. The rate is expressed by the equation : Q_t/C_∞, =1-exp (k'C^1/m), (Fig. 10∼13).

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The methane formation reactions between H₂S and CO were studied over the CoS, MoS₂, Co-Mo, and Ni-W catalysts (at 330∼450°C) for the purpose of producing of hydrogen from H₂S. Methane, H₂, CO₂, COS, CS₂, and sulfur were produced in these reactions. The main reaction path of this reaction was considered to be as follows at first, COS and H₂ are produced from the reaction of CO and H₂S, next H₂ reacts with CO producing CH, and H₂O, then H₂O reacts with COS producing CO, and H₂S. In addition to this main reaction path, a decomposition reaction of COS into CO and sulfur, and a disproportionation reaction of COS into CO₂ and CS₂ were shown to take place.

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A new method for the synthesis of 4-dimethylaminophthalic anhydride [4] J was investigated. The condensation of m-dimethylaminobenzoic acid with formaldehyde in 6 N hydrochloric acid gave 4-dimethylaminophthalide (mp 124∼125°C, yield 39%). The oxidation of the phthalide with sodium m-nitrobenzenesulfonate in 10% aq. sodium hydroxide at 100°C for 13 hrs gave 5-dimethylaminophthalaldehydic acid [2] (mp 146∼147°C, yield 57%). By the further oxidation of phthalaldehydic acid [2] with aq. AgNO₃, 4-dimethylaminophthalic acid [3] was prepared in 72% yield. 4-Dimethylaminophthalic anhydride [4] (mp 205∼206°C, yield 87%) was easily obtained by the dehydration of [3] with acetic anhydride.
The photochlorina.tion of [1] afforded 5-chloro-6-dimethylaminophthalide [5] in place of 4-diinethylaminophthaloyl dichloride.

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Fatsia japonica Decne. et Planch. is an endemic plant of Japan.
The essential oil in leaves and panicles of this plant, was examined in detail.
The yield of oil obtained from fresh leaves and that from panicles were 0. 004∼0. 022% and 0.005%, respectively. The oil consisted of more than 28 components. The major sesquiter-penes were(-) -epi-cubenol, (+)-δ-cadinene, α-muurolene, α-copaene, β-copaene, α-cube-bene, β-bourbonene, and calamenene ; the noticeable monoterpens were 4-terpinenol, linalool, and a-terpineol.
6, 10, 14-Trimethyl-2-pentadecanone was at first detected as a natural product.

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