The structure of catalytic active sites of fluorided alumina catalyst was studied by the methods of X-ray diffraction and 11-1 and 19F broad line NMR. X-ray diffraction analysis found no structural difference between 77-alumina and fluorided alumina, in spite of a remarkable difference in catalytic activities between them. However, the 111 and "F broad line NMR showed that the structural difference between them and that the structural positions of 'H and "F nuclei in the catalyst were localized near the surface of the catalyst particles. These results suggest that the catalytic active sites consist of five different types formed from different number of coordinated F and 0 atoms. The role of these active sites on the catalytic reactions was studied in cumene cracking, o-xylene isomerization and toluene disproportionation reactions over the fluorided alumina.

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The catalytic activity of metal oxides, on which chlorozinc (II) complexes were fixed, was investigated concerning with the isomerization(I) and disproportionation IO of o-xylene as well as the Beckmann rearrangement (III) and dehydration (IV)of cyclohexanone oxime. Of the various catalysts examined, Si0<₂ Al₂O₃ and Si0₂, on which chlorozinc (II) complex was fixed exhibited high catalytic activity toward the above reactions. On these systems, however, the fixation of chlorozinc(II) complexes changed the reaction selectivity to enhance (II) and (IV) and to diminish (I) and (IV). Surface acidity measurements by the Benesi method showed that, with increasing the amount of fixed zinc (II) complex, acid sites (-5.6 ≤ Ho ≤ 3.3) increased, while those (110≤ -5.6) decreased, and that such change in acidity corresponded closely with the observed change in catalytic activity. The thermal stability of the surface zinc(II)complex was examined by chemical analyses after various heat treatments. On the basis of the above result, it was proposed that the decrease of acid sites (H0 ≤-5.6) occurred -due to the loss of surface acidic protons during the fixation of zinc (II) complexes and that acid sites (-5.6≤ Ho ≤3.3) appeared due to the partial decomposition of the fixed complexes; the latter acid sites were either surface OH groups adjacent to zinc (II) or coordinatively unsaturated zinc (II) ions.

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The effect of co-existing substances on the rate of sorption of hydrogen by a palladium sheet exposed to carbon dioxide, methane, oxygen, or carbon monoxide at pressure less than 20 Torr before the sorption experiments. Exposure treatment of Pd sheets with carbon dioxide, methane, or oxygen at room temperature gave no effect on the sorption rate. The oxidation of the surface of Pd sheets at high temperature brought an induction period in the hydrogen sorption. In the case of carbon monoxide, the amount of hydrogen sorbed in a Pd sheet was proportional to the square root of time (Fig.1), but its proportionality constant 77 was lower than that for a clean Pd sheet. The value of i was affected by the exposing pressure of carbon monoxide and pretreatments of Pd sheets (Fig.3). The results were explained with the assumption that the rate-determining step is the hydrogen diffusion process in the 8-phase bringing the a-8 phase transition and that the adsorption of carbon monoxide lowers the concentration of dissolved hydrogen in the vicinity of Pd surface.

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Previously, products, formed when methane-ammonia-water vapor system was submitted to an electric discharge have been studied. The present experiments are concerned with qualitative and quantitative analyses of the decomposition products formed from C₂ hydrocarbon such as ethane, ethylene or acetylene and of the amino acids produced from C₂ hydrocarbonammonia-water vapor system. C₂ hydrocarbon was abundantly formed from methane and probably would exist in interstellar space, e. g. Jupiter and Saturn. The yield of unsaturated hydrocarbons was generally higher than that of saturated hydrocarbons in the single system hydrocarbon alone. Despite the kinds of hydrocarbon product were quite similar with each other in the single system of methane, ethylene or ethane alone, different kinds of product were found in the single system of acetylene alone. Cyclobutadiene was considered to be an important intermediate to elucidate the mechanism of these reactions. As for C₂ hydrocarbonammonia system and C₂ hydrocarbon-water vapor system, the same kinds of amine, cyanide

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The chemical change of sodium hypophosphates by grinding in a box conditioned to temper-ature 20 to 30°C and relative humidity 20 to 30% was investigated by means of X-ray dif-fractometry, IR spectrometry and thermal analysis. Disodium dihydrogen hypophosphate hexahydrate Na₂H₂P₂o₂ H₂o₆ liberated easily the water of crystallization and became type I of the anhydrous salts. The type I of Na₂H₂P₂o₆ was very stable and when ground for long time (ca.340 hr), it transferred to typeII. On the other hand, tetrasodium hypophosphate decahydrate (Na₄P₂o₆10 H₂o) also liberated easily the water of crystallization and became type I of the anhydrous salts. The type I of Na₄P₂o₆ was unstable and converted to the type II on grinding for 24 hr. In Na₂H₂P₂o₂-Na₂Co₃ and Na₂H₂P₂o₆-Na₄P₂o₆ systems, H atoms of Na₂H₂P₂o₆ were exchanged with Na atoms to yield Na4P₂o₆ (with decarbonization) and Na₃HP₂o₆, respectively. Therefore, these H atoms should be ionic. The P-P linkage of hypophosphate is more stable against the grinding than the P-O-P linkage because the former is not severed even after 400-500 hr grinding.

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NdP₅, o₁₄ crystals were grown by liquid phase reaction in phosphoric acid. Facters affecting the growth process were temperature (400-600°C), starting material composition (Nd₂o₃ 16 g in H₃PO₄ 500ml), and reaction container cover weight (0-33g for 6.6 cm internal diameter of container).
The rate of crystal production increased with increasing temperature, increasing Nd concent-ration, and decreasing cover weight. To obtain a transparent crystal with smooth surfaces, growth temperature should be high, Nd concentration low, and the cover heavy. Fluorescence decay time of 1.051μ m wavelength was 110±10 asec for crystals grown at temperatures higher than 500°C.

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The reaction of tetrathionate with sulfite was investigated, and an optin. al pH for its sulfitolysis was found to be in the range 7.7, -12.5 when sulfitolyzed for 20min at room temperature. Under the same conditions as those for tetrathionate, the optimal pH for sulfitolysis was in the range 6.5-8.2 for pentathionate, and 6.9-9.5 for hexathionate. Therefore, each sulfitolysis of tetra-, penta-, and hexathionate could proceed to stoichiometric completion, so far as the pH of the reaction solution is kept in the range 7.7-8.2. Present method for the determination of tetrathionate is based on the formation of thiosulfate equivalent to the tetrathionate by means of its sulfitolysis, and the spectrophotometric measurement of an excess iodine for the thiosulfate. A method for the determination of tetrathionate, thiosulfate and sulfite mixture also is devised. This method consists of three procedures, and the three sulfur compounds in the mixtures give the following equivalents:
Procedure I S₄o₆^2-S₂o₈^2-
Procedure II S₂o₃^2-
Procedure III S₂o₈^2--2 So₈^2-
The absorbance obtained by Procedure I corresponds to the sum of tetrathionate and thiosulfate in the mixtures, because the sulfite is masked by the formaldehyde added for removal of the excess sulfite. The absorbance obtained by Procedure I, in which no sulfitolysis of tetrathionate was carried out, corresponds to the amount of thiosulfate in the mixtures. The absorbance obtained by Procedure III corresponds to the sum of the amounts of thiosulfate and twice as much as sulfite in the mixtures. Thus, the following equations can be derived: (S₄o₆^2-)=I-II, (S₂o₈^2-)=II, and (SO₃^2-)=(III-II)/2, where I, II, and III denote the molar concentration of thiosulfate which was determined from the calibration graph in Fig.1, using the absorbance obtained by Procedure I, II and DI, respectively. Table 2 reveals that the proposed method can be successfully applied to the determination of mixtures of tetra-thionate, thiosulfate and sulfite at various ratios.

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The polarographic behaviours of lead (II) pyrrolidinecarbodithioate chelate were investi-gated in isobutyl methyl. ketone (IBMK) containing O.1 mol/l tetrabutylammonium perchlorate as a supporting electrolyte. D. C. polarograms for lead (III)-pcd chelate in IBMK show two reduction waves at the DME. The half wave potentials of these waves are -0.2-0.3 and -0.8V(vs.SCE). The oxidation waves appear at +0.2 and +0.4V. The oxidation wave is due to the exchange reaction between mercury and Pb (pcd), at the electrode surface of the DME. Lead(II) is quantitatively extracted from an acetate buffer solution with Et4Npcd into IBMK .in the pH trange from 2.5 to p. 0. Using the exchange reaction between extracted Pb (pcd), and mercury, lea can be determined successfuly in the concentration range from 8x 10^-1 to 8 x 10^-5 mol/l. . The oxidation half wave potential is more anodic for the more stable complexes in the order of the stability constants of extracted complexes.

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A new plot which does not involve locating the equivalence point is proposed. A sample solution is titrated with a titrant solution and subsequently with a solution containing a known amount (c, ) of the same substance to be determined. If the volumes which correspond to the identical electrode potential (E) on the titration curves are read off and denoted by VB and vA respectively, the concentration, cx, of the analyte is determined from an intercept of a linear plot of y vs. x:
y-px+ca/cx
where x is a function of E and vB, y is a function of vA and vB, and p is a constant. This method can be applied to the acid-base and complexometric titrations, and has such advantages that neither ionic concentrations nor equilibrium constants are required for the calculation, of concentrations.

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The decomposition products (C₁ to C₉ fluorinated compounds) of ethylene- and propylenetetrafluoroethylene copolymers (ETFE and TFEP) were identified and determined, after heating the polymers isothermally or dynamically in inert gas atmospheres. Kinetic analyses on the decomposition were also carried out for the two polymers.
There were little differences in the degradation products between ETFE and TFEP. ETFE, however, tends to decompose into low molecular weight compounds without secondary decom- position at high pyrolysis temperatures, and to give C₅ and C₆ compounds through cyclic transition structure at low pyrolysis temperatures.
Kinetic analyses show that while ETFE follows a random degradation with an activation energy of 49.1 kcal/mol, the decomposition of TFEP obeys the first order reaction with an activation energy of 59.7 kcal/mol. There was a great differences in the values of frequency factor between the isothermal and the dynamic measurement; this phenomenon is seemed to be due to structural changes of the polymers during the heating to the preset temperatures.
TG-MS method was also applied to the analysis of the degradation products, and fluorinated compounds from C₂ to C₆ were observed at all degradation temperature ranges showing no specific species as compared with the results of pyrolysis-gas chromatography.

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The oxidation of phenol with peracetic acid was investigated for the industrial preparation of benzenediols and the reaction conditions were optimized. The effect of additives was essentially important to improve the yield of the benzenediols. Effects of temperature, phenolperacid ratio were also investigated, and the optimum conditions were determined as carrying the reaction of phenol 1 mol with peracetic acid O.1 mol in the presence of O.2 g of additives at 60°C without solvent, where 85 mmol of phenol was converted into ca.45 mmol of catechol and ca.35 mmol of hydroquinone. The best additives were chelating agents, phosphates and condensed phosphates, which are well known peroxide stabilizers. As the simple stabilizing effect on peracid cannot interpret the whole phenomena, suppressing effect on the metal-catalyzedoxidation of benzenediol was estimated. Oxidation of cresols and aromatic ethers with peracetic acid was also investigated.

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Studies were made on the relation between the pyrolysis and the decomposition by electron impact of tris (2-hydroxyethyl) isocyanurate (THEIC), tris (2-hydroxypropyl) isocyanurate (THPIC), and tris (2, 3-dihydroxypropyl) isocyanurate (TDHPIC).
These samples were found to decompose thermally via 2-oxazolidinone derivatives to give liquid polymer. THEIC was completely converted into 2-oxazolidinone as the intermediate product in pyrolysis. Activation energies for pyrolysis were calculated from the DTG curves (Table 2).
R: CH₂CH₂OH (THEIC)
CH₂ CH₂CH(0H)CH₃(THPIC)
CH₂CH(OH)CH₂OH(TDHPIC)
In the decomposition by electron impact, the molecular ion peaks were not detected, but the (M+1)+ ion peaks were recognized instead. The base peak and one of the strong peaks in all these samples correspond to (I) and (II), respectively. The fragmentation may take place in three paths. One path starts from fission of a triazine ring of the molecular ion directly. The other two paths result from fissions of triazine rings giving mfe 143 and mle 130 fragment ions as the intermediates (Scheme 5).

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The yellow powdery preparation (refered to as Mo-y), made of molybdenum powder and hydrogen peroxide, exhibits the Lewis acid chracter, and acts as a catalyst for "Cumene-process". The decomposition rate of 1-methyl-l-phenylethyl hydroperoxide (common name: cumene hydroperoxide, CHP) increases with the content of Mo-y, but there is an optimum content of Mo-y for the formation of phenol from CHP. The decomposition reaction of CHP proceeds stoichiometrically, when 1 drns solution of 3.97 g of Mo-y and 1 mol of CHP in cumene is heated at 60°C. The activation energy is estimated as 21.4 kcal/mol in the low temperature region (at 40-60°C) and as 3.6 kcal/mol in the high temperature region (at 70-80°C). When CHP is contaminated with water or 2-phenyl-2-propanol (from 1.6 to 8.5% (mol)), the drop in reactivity of Mo-y for the formation of phenol is observed. The high reactivity of Mo-y with the hydroxy compounds appears to be responsible for the retardation.2-Pheny1-2- propanol is dehydrated to a-methyl styrene by Mo-y.

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A convenient method for synthesizing 3, 5-diary1-1, 2, 4-dithiazolium salts (2a-g) was deve-loped: the reaction of arencarbothioamides with iodine or some reagents, . behaving a similar manner as iodine, gave the dithiazolium salts.
In addition, hydrogen sulfide was passed into a nitrile-iodine mixture in a appropriate solvent to give a dithiazolium salt directly. These dithiazolium salts gave 3, 5-diaryl-1, 2, 4-thiadiazoles (1 a, b, c), 3, 5-diaryl-1, 2, 4-triazoles [3 a, b, c] or 3, 5-diaryl-1, 2, 4-oxadiazoles (4 a, b, c), respectively, in good yields by treatment with ammonia, hydrazine, or hydroxylamine.

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Manganese nodules, after pulverizing, were oxidized by heating and were leached with dilute acid. The leaching was carried at 95°C for 5 hr using 120 ml of 0.1 N hydrochloric acid per 1 gram of the sample oxidized at 500°C for 3 hr. By these treatments, 99.2% of copper, 68.2% of nickel and 36.5% of cobalt were extracted. By the foam treatment of the leached solution with the aid of N-decanoyldiethylenetriamine, copper and nickel were recovered selectively without interference of the co-existent heavy metal ions. Studies on the conditions of the foam treatment of the leached solutions of various comositions revealed that, by applying the suitable conditions, copper, nickel and cobalt could be recovered selectively as foam. It was also found that the co-existence of aluminum ions enabled us to recover copper selectively without accompanying iron (III) ions.

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Two convenient synthetic methods of a new condensed-ring compound, 5 H-pyrido[1', 2': 1, 2]pyrimido[4, 5-6]acridine-7, 15-dione [3] were found. One of them was the dehydrogenation of 6, 14-dihydro-5 H-pyrido[11, 2': 1, 2]pyrimido[4, 5-b]acridine-7, 15-dione [6], formed by the reaction of 2-anilino-3-ethoxycarbonyl-1, 4-dihydro-9(10 H)-acridinone [5] with 2-aminopyridine in the presence of acid. The other was the cyclization of 8-anilino-7- ethoxycarbonylpyrido[2, 1-b]quinazolin-10-one [11] which was obtained by the dehydrogenation of the condensation product of 7-ethoxycarbonyl-6, 9-dihydro-8-hydroxypyrido[2, 1-b]quinazolin-10-one [10] with aniline.
The compound [3] was orange microcrystalline powder and exhibited the polymorphism. Some properties of [3] as a pigment, such as color, the resistance to light, heat, acid alkali, and organic solvents, were also examined in comparison with those of quinacridone. On the basis of these results, it became clear that [3] had excellent pigment properties similar to those of quinacridone.

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For the purpose of preparing glassy carbon from thermoplastic resins, spherical particles of polystyrene were made infusible by the sulfonation and pyrolyzed at 200-1600°C. The following three methods were performed for sulfonation; (a) sulfonation of polystyrene particles with SO₃ gas, (b) sulfonation of the polystyrene solution in C₂H₄Cl₂ with the mixture of fuming sulfuric acid and C₂H₄Cl₂ (1:1), and (c) direct sulfonation of polystyrene particles with fuming sulfuric acid. The last method was most effective to obtain infusible cross-linked polymer as shown in Table 1. Spherical hard carbon particles of 100-150μ diameter were obtained by pyrolyzing the sulfonated polystyrene at high temperatures. Carbonization process were pursued by micrograph, the measurement of weight loss, elemental analysis, and so on (Figs.1-3). X-ray diffraction patterns of carbon formed were very analogous to those of a phenolic resin carbon, and the crystal parameters, d₀₀₂, L_c, and L_a showed the characteristic values for non-graphitizable carbon. The stability against air oxidation measured by differential thermal analysis was comparable to that of glassy carbon (Fig.4). BET surface area, density, and micro-Vicker's hardness were also measured as a function of heat treatment temperature (Figs.5-7), and were compared with the results for glassy carbon. As the results, the carbonaceous products from sulfonated polystyrene were found to be non-graphitizable hard carbon with the functions equivalent to usual glassy carbon from thermosetting resins.

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The polymerization of vinyl acetate in various solvents was carried out at 30°C under irradiation of the wave length 366 nm and by using azobiscyclohexanecarbonitrile (ACN) as a photo-sensitizer. The rate of polymerization (R_p) changed markedly and increased in the following order with respect to solvents ethylbenzene>chlorobenzene>o-dichlorobenzene> toluene >benzene > 1, 1, 2, 2-tetrachloroethane > cyclohexane >1, 2-dichloroethane.
The rate of initiation (R₁) scarcely changed in these solvents, while the values of 2 k_t/k_p changed markedly in them. The values of 2 k_t/k_p were obtained by means of rotating sector method. The propagation rate constant k_pand termination rate constant (2 k_t)were derived on the basis of the values of 2 k_t/k_p²8², and 2 k_t/k_p. The values of kp changed markedly in these solvents, while those of kt changed a little in them.
It was considered that the remarkable change in R_p was dependent on the noticeable change in kp due to the interaction between solvent and propagating radical. The interdependence between kt values and the initial viscosity in this polymerization could not be found.

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Removal of nitrogen oxide (NO_x) from stationary sources was studied by adsorption of NO formed by the catalytic oxidation of nitrogen monoxide (NO). The adsorption measurements were carried out by using flow reactors (U-shaped glass tube, ID: 10 mm, and glass tube, ID: 21 mm) under atmospheric pressure and at 19-65°C. The adsorption of NO₂(about 500 ppm level) on some commercially available adsorbents was measured by a continuous method. For practical use, some zeolities adsorbed a sufficient amount of NO₂, that is, 1.41-5.78 g NO₂/100 g solid (Table 2). The zeolite of mordenite system was acid-stable. The oxidation of NO adsorbed on zeolite surface was retarded by H₂o, CO, , and NO₂. The effective oxidation of NO occurred when the concentration of H₂o in effulent gas was less than ca. O.04%. The oxidation of NO was not affected by the presence of SO₂ (200 ppm level), and was simultaneously removed. Desorption of NO from zeolite surface was carried out at 200-500°C. It has been shown that NO_x was adsorbed in the form of NO, NO₂, and (NO)_x(NO₂) as a result of the interaction between NO and NO₂.

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The supported state of Fe³⁺ ions in supported iron oxides prepared from iron (III) nitrate and carriers and thermal evacuation effect on the supported iron oxides have been studied by the ESR method. Several different spectra were obtained for different carriers. Relatively sharp spectra obtained can be explained in terms of the difference in coordination states of Fe³⁺ ion. The absorption intensity on the sharp spectra is lower at higher evacuation ternperatures. Relatively broad spectra obtaind seem to be due to the cluster of the iron oxide on carrier surfaces. Their absorption intensity increases with increasing evacuation temperature and absorption centers shift at higher temperatures.

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The adiorption of- NO on a-, 8-, and r- FeOOH has been measured by means of a gravi metric, method at 30°C. The adsorption isotherms below 100 Torr were well expressed by the Langmuir formula. The Langmuir constant b (Table 1) had value characteristic of the surface structure of each adsorbent and was defined by the geometrical positions of reasonable chemi- sorptive sites on the predominant crystallographic surfaces. The chemisorptive sites seemed to be o^2- for a- and j9-FeOOH and OH- for r-FeOOH. The effect of heat treatment of each FeOOH in vacuo on the NO adsorption was also examined and it was found that the samples prepared by calcinating any FeOOH at 500°C adsorbed considerably large amounts of NO (ca.10-15×10^-3 mmol/m², see Figs.3, 4, and 5).

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Hydrous titanium oxide obtained from ilmenite treated with sulfuric acid was suspended in a 3-5.8 mol// NaOH solution, which was then heated for 4 hr either at boiling point (104 to 110°C) under atmospheric pressure or 150°C in an autoclave. The resulting solution was diluted with water, solid matter remained being filtered off. The solubility of the cake thus obtained in dilute sulfuric acid increased with increasing concentration of sodium hydroxide, more than 90% of the cake being dissolved in the acid when the alkali concentration exceeded 5 mol/l. Results of chemical and X-ray analysis of the cakes revealed that Na₂Ti₄o₉, Na₂Ti₅o₁₁and Na₂Ti₆O₁₃ are formed by the alkali treatment of the hydrous titanium oxide.

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By the reaction of potassium 1-naphthalenesulfonate with 2.4-fold moles of sodium hydride in butylamine at 140°C for 7 hours, N-butyl-1-naphthylamine was obtained in a 86% yield, accompanied with naphthalene, 1-naphthylamine and dibutylamine as by-products. Various arenesulfonates with sodium hydride in alkylamines (R =Et, Pr, Bu, cyclohexyl) or arylamines (Ar = Ph, p-tolyl) gave the corresponding N-alkylarylamines or diarylamines in good yields. In contrasts to the alkylamination, no aromatic hydrocarbon was formed by the arylamination. Arenesulfonates with sodium hydride in ethylenediamine gave N-arylethylenediamines.

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The syntheses of triphenodithiazine (5, 12-dithia-7, 14-diazapentacene) [5a] and its homolog were possible by dechlorination of their 6, 13-dichloro derivatives which were prepared by condensation of aminobenzenethiols with chloranil in good yield. The dechlorination was easily carried out by tin powder in polyphosphoric acid. For example, 6, 13-dichloro derivative of [5a] [4a] was converted to [5a] in 52.7% yield.
Similarly, 3, 10-dichloro [413], 3, 10-dimethyl [4d], 3, 10-dimethoxy [4e], 3, 4: 10, 11-dibenzo [4f] derivatives of [4a] were reduced to corresponding chlorine free compounds [5]. As a result, a new preparative procedure for synthesis of [5] from 6, 13-dichlorotriphenodithiazines [4] was developed. Replacement of chlorines by hydrogens in these heterocycles brought about a decrease in melting point and hypsochromic shifts in electronic spectrum as in the case of triphenodioxazines.

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The bromination of Phenothiazine [1] with bromine in several solvents at 30°C was carried out.1, 3, 7, 9-Tetrabromophenothiazine [2] was obtained in the yields of 92, 87 and 54% by. use of excess bromine in chloroform, nitromethane and acetic acid, respectively. In carbon tetrachloride, however, excess bromine gave unidentified dark purple crystals, seemingly a Br₂-adduct of 3, 7-dibromophenothiazine [3]. This gave [3]in 90% yield on treatment with dioxane at room temperature or with boiling carbon tetrachloride.

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Effect of water added on the distillation of the mixture of 1-chloroacetone (bp 119.7°C at 1 atm), MCA, and 1, 1-dichloroacetone, (bp 118.5°C at 1 atm), DCA, has been studied. The respective vapor-liquid equilibrium in the systems of MCA-DCA, . and MCA-DCA-H₂o, the relation between moles of distillates, ' D, and moles of feed, F, and the composition of distillates in the MCA-DCA-H₂o system have been measured, for MCA has the boiling temperature similar to that of DCA and the mixture of MCA and H₂o has the boiling temperature similar to those of the mixture of DCA and H₂o.
Results showed that an efficient and successful separation of MCA and DCA from their mixtures probably increases difference in volatility, between MCA. and DCA.

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