The acid dissociation constants of 1-(p-substituted phenyl)-1, 3-butanediones (p-XC₆H₄COCH₂⋅COCH₃ X=NO₂[1], COOH[2], COOCH₃ [3] Br[4], Cl[5] H [6], NHCOCH₃ [7] CH₂H₅[8], CH₃ [9], OCH₃[10], OH [11] and NH₂ [12]) were determined by a potentio metric titration in dioxane-water (3: 1 v/v) at 25±0.2°C. The ionic strength of the solutions was adjusted at 0.1 with potassium nitrate. The pK_do. of enolic proton increased in the order of [1] (9.26)<[2] (9.69)<[2] (2.77)<[4]=[5] (10.11)<[7] (10.47)<[6] (10.53)<[8]=[9](10.78)<[10] (10.93)<[11](11 08)<[12](11.57). It was found that the basicity of these compounds increases as the substituent becomes more electron-donative, and that the intramolecular hydrogen bond is strengthened as the basicity increases.

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In order to improve the durability of Raney-type copper oxide catalysts, CuOCu-Al-Cr oxide catalysts were prepared by oxidation and calcination in air of Raney copper, which was prepared by leaching Cu-Al alloy with dilute sodium hydroxide aqueous solution containing (NH₄)₂CrO₇. The yield of Cu-Al-Cr oxide rises to a maximum at 530°C in the c alcination temperature range of 400 to 550°C. The catalytic actjkvity of CuOCu-A1-Cr oxide for oxidation of CO was found to increase with increasing content of Cu-Al-Cr oxide. Though the catalytici activity for oxidation of CO is rather lower than that of CuO, the Cu-Al-Cr oxide is excellerit in thermostability and durability under hydrothermal conditions. In the case of IPA decomposition, the catalytic activity for dehydrogenation of Cu-Al-Cr oxide was nearly equal to that of CuCr₂O₄. The crystal structure of Cu-Al-Cr oxide, CuAl_1.09Cr_0.91O₄, was found to be dependent on temperature; in the range of 400 to 700°C, - lattice constant α=8.23 A (cubic), and lattice strain η= 0.016, while in the range 700 to 900°C, α=8.37Å, c/α= 0.940 (tetragonal), η=0.0064. The amount of active oxygen of the latter, measured by hydrazine m ethod, was less than that of the former.

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Hydrogenation of carbon monoxide over the supported rhodium catalyst to produce hydrocarbons (C₁ to C₄) and a trace amount of oxygenated compounds was studied. The product distribution was sensitive to the ratio of CO/H₂, the reaction temperature and the support. Compared with the iron, nickel and ruthenium catalysts, the rhodium catalyst has more selective for the formations of ethylene and propylene. From the measurements of the infrared spectrum and chemisorption amount of carbon monoxide on the supported rhodium catalyst, it was found that the chain growth of the hydrocarbons is dependent on the surface coverage of carbon monoxide, i. e. the strength of the surface bond between rhodium and carbon.

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The preparations, the activities and the structures of the nickel-carbon catalysts, which changed the degrees of nickel dispersion, were studied. The catalysts were prepared by the exchange of Ni²⁺, hexaamminenickel(II) ion and tris(ethylenediamine)nickel(II) ion or by the impregnation with nickel (IC) nitrate on a cation exchangeable active carbon.
It was found that when the catalysts were calcinated in nitrogen, the nickel oxide, which was produced by decomposition of nickel salt, was reduced immediately to nickel by carbon monoxide yielded by decomposition of the surface acidic groups on the active carbon support. The ammine exchange-type catalyst was reduced most easily with carbon monoxide, because of the high nickel dispersion in comparison with other catalysts. The nickel supported on the ion exchange-type catalyst was dispersed well on the support, and it was excellent in heat resistance. On the other hand, the nickel supported on the impregnation-type catalyst was easily crystallized. The activity of the active carbon-nickel catalysts for dehydrogenation of 2-propanol was influenced considerably by the methods for the catalyst preparation, by the temperature of heat treatment and by the amount of supported nickel, but the activity did not depend on the reduction temperature. t Studies on Preparations and Catalytic Properties of the Carbon Supported Nickel Catalysts. IV.

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Vapor-phase synthesis of indole from phenylhydrazine and paraldehyde was carried out at 280°C over basic metal oxides and their binary oxides with silica. Acid-base properties of oxide catalysts were compared with the results of indole synthesis. The amount of uptake of pyridine by binary oxides such as SiO₂-MgO and CaO-SiO₂, was much larger than that by the component single oxides, showing the appearance of acidic properties in binary catalysts. The acid strength was small and pyridine was desorbed reversibly under nitrogen at 300°C. In the case of strongly acidic Al₂O₃-B₂O₃, irreversible adsorption of pyridine was observed under the same conditions. It was observed that binary catalysts such as SiO₂-MgO and CaO-SiO₂retained some basic properties by the adsorption of acetic acid. CaO was inactive for both depolymerization of paraldehyde and for cyclization of phenylhydrazone, while CaO-SiO₂ and SiO₂-MgO were effective for indole synthesis. Thus, the acidic sites in these binary oxi des are considered to contribute to the formation of indole ring. However, preadsorption of acetic acid on CaO-SiO₂ and SiO₂-MgO resulted in a decrease in the yield of indole, suggesting a cooperative effect of acid-base properties. Strongly acidic catalyst such as Al₂O₃-B₂O₃ was rapidly deactivated probably due to the strong adsorption of nitrogen bases. Catalysts with weak acidity might be preferred.

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The characteristics of silver pyrophosphate solution have been examined from the conductivity and kinematic viscosity of solutions. The cathodic polarization curves excluding concentration polarization were determined by the use of a rotating disk electrode to investigate electrode reactions in silver electrodeposition. Each conductivity of solutions of potassium dicyanoargenatate( I ) K[Ag(CN)₂], potassium pyrophosphate K₄P₂O₇, potassium th iocyanate KSCN and the mixed solution appears to have an additive property (Fig.1). The kinetic viscosity was confirmed to be temperature dependent and the apparent activation energy E_c was 3.1 kcal/mol (Fig.2), and the overall electrode reaction in K[Ag(CN)₂]-K₄P₂O₇ solution can be written as follows:
[Ag(CN)₂]-+e→Ag+2CN-
The effect of ionic diffusion on the reaction was observed. The diffusion coefficient of this solution at the Ag⁺ concentration of 0.07 mol/l at 25°C was 1.39×10^-5cm/s and the Schmidt number was 718 (Fig.4). From the cathodic polarization curves, Tafel slope of 0.346 V was observed in the range of approximately -0.45∼-0.60 V (SCE) (Fig.7). In the charge transfer process in this range, the value of apparent coefficient α was 0.268, the apparent valence n was 0.638, the exchange current density i_o was 3.8 mA/cm2, and the apparent activation energy E_c was 7.7 kcal/mol (Fig.3 and Table 3). The activation overvoltage for hydrogen evolution from K₄P₂O₇ solution was higher than that from K[Ag(CN)₂]-K₄P₂O₇solution (Fig.9).

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The absorbance change at 380 and 240 nm with time during the reaction of sodium chlorate and iron (II) perchlorate in 2 mol⋅dm^-3 perchloric acid was measured by stopped-flow spectrophotometry. The absorbance change with time at 380 nm showed the apparent and irregular formation and decay of chlorine dioxide, and that at 240 nm showed the formation of iron (III )ion. These spectral changes are confirmed to be due to the consecutive reactions involving chlorine dioxide as an intermediate.
The rate constant for the formation of chlorine dioxide in the reaction of chlorate ion with iron (II) ion, k_c, was calculated by Koutecky's equation for catalytic current measured by D. C. polarography, and that of reduction of chlorine dioxide with iron (II), k, was measured by stopped-flow spectrophotometry. In 2 mol. dm^-3 perchloric acid at 25±0.1°C, the values of k_c and k were found to be 4.04 and 6.83±10³dm³⋅mol^-1⋅s^-1 respectively. The rate law for chlorine dioxide was given by
-d[ClO₂]/dt= k⋅ [ClO₂]⋅[Fe²⁺] On the basis of these results (k_c/k≅6×10^-3) and stoichiometric relation, the rate-determining step in the reaction between chlorate ion and iron (II) ion was confirmed to be the formation reaction of chlorine dioxide, i. e.
ClO₃^-+Fe²⁺ H⁺→ClO₂+ Fe³⁺+OH^-

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The crystallization of CoFe₂O₄ by aging Co-Fe hydroxide gels prepared by the addition of mixed FeCl₃ and CoCl₂ solution into caustic alkaline solution has been investigated. During the procedure of crystallization, the Co-Fe hydroxide gels were kept in the magnetic filed of 10000 gauss for several hours at 98°C. The substance aged up to 98°C in the magnetic field containtheedw ateorf 9 w t/0. T lies pecisfiucr facaere aw as133m2/gsp, ecifgirca vity. 4.32, and crystallite size 12.2 nm, while the sample prepared without the application of magnetic field, showed the values 21wt%, 147.3m2/g, 3.36 and 4.1 nm, respectively. On the other hand, the substance aged for 5 h in the magnetic field contained the water of 6 wt%, specific surface area 82.1 m2/g, specific gravity 4.33, and crystallite size 14.8 nm, while the sample produced without the magnetic field, had the values 7 wt%, 80.0 m2/g, 3.94 and 13.5 nm, respectively.
The samples aged in the magnetic field thus resulted more favourable for the crystallization than the one aged withou' t the magnetic field at the earlier aging stage. However the surface area, specific gravity, and of crystallite size for the aged sample in the magnetic field were still inferior to those prepared by the ignition of the gels at 1200°C for 5 h.

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A simple and convenient device was designed and constructed to observe the temperature dependence of ligand field absorption bands and ligand field bands' of aqua complexes and ammine complexes of d¹∼d⁹ ions of the first transition series were observed at various low temperature from liquid nitrogen temperature to room temperature. A plot of their wave numbers against temperature gave a straight line. The slope of the straight line was correlated with the slope of the curve of the Tanabe-Sugano diagram.

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A commercial standard gas generator was partially reconstructed and third component gas mixer was made by authors to make the mixing possible at any desired concentrations of three kinds of gases. The burner and gas sampling tube were designed for the analysis of generated gas by means of both infrared and chemiluminescence spectrometries. The results obtained are summarized as follows.1) A linear relationship was observed between the gas concentrations of wide range and infrared absorption due to NO (1∼5000 ppm) and NO₂ (1∼1000 ppm) by the use of 10 cm and 20 m gas cells.2) Quantitative and simultaneous analysis of following NO, NO₂ and NH, in flue gas produced by combustion was achieved by the use of the gas sampling tube and the reconstructed standard gas generator system. Since a linear relationship was also indicated between the concentrations and absorptions.3) Quantities of NO and NO₂ in the gas produced by the combustion of model fuel, a mixture of propane and air, w ere effectively measured to discuss the relation with the quantity of NH₃ added in the fuel or in the gas produced.
The quantities of NO and NO₂ determined by the proposed method were in approximate coincidence with those obtained by chemiluminescence method.

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¹³C-NMR spectra of N, N, T: diethylaniline (DEA) adsorbed on silica gel (LS 310) and octadecylsilanized silica gel (ODS-silica, LS 410) were observed. ¹³C-spin-lattice relaxation times (T¹) of DEA were also measured in liquid state and in adsorbed states. Large chemical shifts were found for DEA adsorbed on silica gel, whereas DEA adsorbed on ODS-silica gave small chemical shifts (Table 1). These results suggest the weaker interaction of DEA with ODSsilica. compared to that of silica gel. Adsorption of DEA on the surface of the silica gel or ODS-silica resulted in the decrease of T¹ Methyl carbon of the adsorbed states gave a long T¹, because of its free rotation. Correlation times evaluated from T¹, data provided the evidence of the remaining free rotation of methyl carbon and indicated the different mecha- nisms of adsorption on silica gel or on ODS-silica.

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A pH titration method for the analysis of binary mixtures of the weak and strong acids is presented. A sample solution of volume V is titrated with a strong base of concentration CB and subsequently with a solution containing a known amount (c_A) of the weak acid to be determined. The volumes, which correspond to the identical pH value on the titration curves, are read off and denoted by υ_B and υ_A, respectively, and concentrations of the weak and strong acids, c_W and c_S, are determined from the slope and intercept, respectively, of a linear plot of y vs. x:
_??_
where x is a function of υ_B, υ_A and pH, and y is a function of υ_B and pH.
The present method has such advantage that dissociation constants of the weak acid are not required for the' calculation of concentrations, and is also utilized for the determination of weak acid and its salt in their mixture.

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Extraction behavior of germanium(IV) from aqueous oxalic acid solution with trioctylamine (TOA) in xylene was investigated to determine the composition of a germanium(IV) species in the organic phase, The stoichiometry of the organic germanium (is, ) species was determined by the mole ratio method, the slope ratio method and the continuous variation method. Mole ratios of germanium (IV) to oxalate and oxalatogermanium (IV) complex to TOA were found to be 1: 3 and 1: 2 in all methods, respectively. The component ratios of the extracted germa- nium (IV) species were also investigated with extraction curves of germanium(IV) and oxalate. Component ratios of [oxalate/Ge(IV) ETOA/Ge(IV)] and [oxalate/TOA] in the organic germanium (IV) species were obtained to be 3.0, 2.1 and 1.5, respectively, at a constant mole ratio of 4.0 for [oxalate/Ge(IV)] in the aqueous. The effect of hydrogen ion concentration on the distribution ratio (D) of germanium (IV) was also determined. A slope of the plot of to D vs. pH of the aqueous phase was about 2.0 at the equilibrium. With respect to the effect of TOA concentration the plot of log D vs. log [R₃N]_(O) (R is octyl group) yield a slope of about 2.0. These results suggest that the oxalatogermanium (IV) species is associated with two molecules of R₃NH+. Based on these observations we come to a conclusion that the extracted germanium (IV) species in the organic phase predominantly consists of (R₃NH)₂Ge(C₂O₄)₃.

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In the reaction of terephthalic acid (TPA) with a large excess of ethylene oxide (E0) in the presence of tetraethylammonium terephthalate (AT) catalyst, the rates of the formation of ethylene glycol ester (A) and diethylene glycol ester (B) are expressed by the equations ( 1 )and ( 2 ), respectively:
_??_

_??
The product ratio B/A increases linearly with the conversion of terephthalic acid and the slope of the straight line decreases as the amount of the catalyst increases. Ester B may be generated by further addition of EO to, A once formed by reaction of terephthalic acid with EO, and terephthalic acid takes part in this reaction as a catalyst. The amount of B form ed in the reaction of terephthalic acid with EO is extremely smaller than that formed in the reaction of EO with substituted benzoic acid which is soluble in EO. This may be due to the fact that terephthalic acid is hardly soluble in EO.

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The diazotization and hydrolysis of p-aminobenzaldehyde were investigated for the purpose of industrial preparation of p-hydroxybenzaldehyde and to find the optimal conditions for these reactions. The preparation of p-aminobenzaldehyde sulfate was carried out rapidly at, 70∼90°C by use of dilute sulfuric acid and the diazotization of P-aminobenzaldehyde sulfate was performed by means of an ordinary method. Upon hydrolyzing the diazonium salt by use of water alone as a hydrolysis agent, the yield of p-hydroxybenzaldehyde was nearly quantitative. t Studies on Industrial Preparation of p-Substituted Benzaldehyde Derivatives from P-Nitrotoluene.

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A series of oligomeric anthraquinones including 5, 5'-dichloro-1, 1'-bianthraquinone [2] 5, 5"-dichloro-1, 1': 5', 1"-teranthraquinone [3] and 5, 5'"-dichloro-1, 1': 5'', 1"': 5", 1''' quateranthraquinone [4] have been obtained by the Ullmann reaction of 1, 5-dichloroanthraquinone with copper powder in nitrobenzene. Several dehalogenated products (e. g.5-chloro-1, bianthraquinone[9])and amines (e. g.5, 5'-dichloroN-phenyl-1, 1'-iminodianthraquinone[6]) were also found to be formed in low yields. The isolated yields of oligorners [2]-[4]were almost identical with those calculated by a random distribution method. The reaction conditions for [2] were optimized with respect to the ratio of copper to [1].

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The reactions of aromatic nitrile oxides with some N-aryl-S, S-dialkylsulfimides [1] were scrutinized for clues to the intermediacy of nitroso compound [8] in the reaction leadin g to benzimidazole 3-oxides [2] and/or 1, 2, 4-benzoxadiazines [3]. The scope and limitation of the reaction were also examined. Isomerization of nitrile oxides to isocyanate [5] was observ e d in this reaction in addition to the formation of [2] and [3]. The isomerization becam e much more predominant in comparison with the formation of [2] and [3] in the reactions with N-(p-nitrophenyl)sulfimides having bulkier S-substituents. The results imply that the nu cleophilic interaction of a nitrile oxide with [1] may lead to the isomerization to give [5] and the nucleophilic attack of [1] onto the nitrile oxide carbon atom may lead to [8] wh ich gives rise to [2] and [3].

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The phenolic sesquiterpene ketone sesquichamaenol, isolated from the Benihi tree (Chamaecyparis formosensis Mathum. Cupressaceae), was synthesized through a new synthetic route and was, converted to some naphthalene derivatives. Starting from 3- (2-methoxy-5-methylbenzoyl) propionic acid [5], 5- (2-methoxy-5-methylpheny1)-6-methy1-2-heptanone [1b] was synthesized in 4 steps. Sesquichamaenol, 2- (1-isopropy1-4-oxopenty1)-4-methylphenol [1a] was obtained by demethylation of [1b] with hydrobromic acid. Reduction of [1b] produced 5- (2-methoxy-5-methylpheny1)-6-methy1-2-heptanol [9], which was then cyclized with hydrobromic acid to give a mixture of some tetrahydronaphthalenes. By heating the cyclized mixture with Pd-C, 1, 8-dimethyl-4-isopropylnaphthalene [3], its 1, 5-dimethyl isomer [14], 3, 4-dihydro-4, 5-dimethyl-8-isopropyl-1 [2H] -naphthalenone [16], its 4, 8-dimethy1-5-isopropyl isomer [17], and 2, 2, 5, 6-tetramethyl-2 H-naphtho[1, 8-bc]furan [18] were obtained. The reaction of 2-methyl-6- (2-methoxy-5-methylphenyl) -2-heptanol [10], an intermediate for the synthesis of elvirol [2] with hydrobromic acid also gave the same products.
These results indicate that the cyclization of [9] or [10] with hydrobromic acid proceeds via spiro-cyclic cation to give 1, 8-dimethy1-4-isopropyl-5-methoxy-1, 2, 3, 4-tetrahydronaphthalene [12A] and its 1, 5-dimethy1-8-methoxy isomer [13] The IR and NMR spectra of [12A] were different from those of [12B], which was obtained ag-a -by-product during the dehydrogenation of 3, 4-dihydro-1, 8-dimethy1-4-isopropyl-5-methoxynaphthalene [24B] BD. The transand cis-configuration are tentatively assigned to [12A] and [12B], respectively.

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(N, N-Disubstituted N', N"-diphenylenemelamino) pyromellitimide-m-phenylenepyromellitimide copolymers were synthesized in N, N -dimethylacetam ide by the condensation of a mixture of m mol of 2- (disubstituted amino) -4, 6-bis (p- or m-aminoanilino) -1; 3, 5-triazine and n rnol of m-phenylenediamine with (m+n) mol of pyromellitic dianhydride. Intrinsic viscosity of the copolymers ranged from 0.22∼0.73 di/g. In the case of the copolymer having a benzyl substituent on melamine ring, the copolymers were soluble in DMA, DMSO, NMP, DMF and pyridine, even when the content of m-phenylenepyromellitimide moiety in copolymer went up to 40∼50 mol%. With bulky substituents on the 1, 3, 5-triazine ring, solubilities of the copolymers were better even in the presence of high content of m-phenylenepyromellitimide in the copolymers. The decomposition temperature of the copolymers was as high as that of polyt [(N, N-disubstituted N'-N''-diphenylenemelamino) pyromellitirnides]. The thermal decom position of the copolymers are considered to be initiated with fission in the substituted melamine ring.

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New poly (amide imide)s containing the bicyclooctene ring in the chain were synthesized in N, N -dimethylacetamide (DMA) by condensation of 7- ( chloroformyl)b icyclo[2.2.2 ]oct-5-ene2, 3-dicarboxylic anhydride (BTR-Cl) with various diamines. BTR-Cl was prepared by the reaction of bicyclo[2.2.2]oct-7-ene-2, 3, 6-tricarboxylic acid 2, 3-anhydride (BTR) with thionyl chloride. BTR-Cl reacted with a diamine at -15°C, and then the temperature was slowly elevated to 166°C. The reaction mechanism for the"formation of these polymers was investigated by the IR spectra of the initial reaction products. The reaction appeared to proceed in three steps;( 1 ) the dehydrochlorination reaction, ( 2 ) the polyaddition reaction and ( 3 ) the imi-C dation, similar to the mechanism of poly (amide imide) s formations. The imidation took place at 130°C in the case of these poly (amide imide) s. The intrinsic viscosities of the polymers ranged from 0.15∼0.63 dl/g. These polymers were thermally less stable than aromatic poly (amide imide) s. However, these polymers were soluble in the solvents such as N-methylpyrrolidone, N, N-dimethylformamide and DMA to obtain the polymer solution easily in such a high concentration as 30 g/100ml

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The homopolymerization of acryloguanamine (2, 4-diamino-6-vinyl-1, 3, 5-triazine) and the copolymerization of this with acrylonitrile in the presence of acid were investigated in dimethyl sulfoxide (DMSO) at 60°C using α, α'-azobisisobutyronitrile as an initiator. The rate of polymerization of acryloguanamine hydrochloride was less than that of free acryloguanamine, and Q and e values of the former were larger than those of the latter. This suggested that the reactivity of polymerization of acryloguanamine could be controlled by the addition of an acid.
When the copolymerization of acrylo- and/or methacryloguanamine (2, 4-diamino-6-isopropeny11, 3, 5-triazine) with acrylic and/or methacrylic acid was carried out under above-mentioned conditions, a highly alternating excellent copolymer was easily obtained, which could be due to hydrogen bonding formed by an interaction between a weak base of amino-1, 3, 5-triazine ring and unsaturated carboxylic acid. Methacrylic acid-methacryloguanamine copolymers containing 31∼75 mol% of triazine rings were soluble in DMSO, readily soluble in either acid or alkaline aqueous media, and insoluble in aqueous solution whose pH showed near neutral values. The titration curves of these copolymers in alkaline solution were similar to that of poly (methacrylic acid). The reduced viscosity increased with dilution in the case of acid or basic solution, but decreased linearly in the case of aqueous sodium chloride solution or DMSO. These results indicated that the copolymers were ampholytes. The isoelectric point of these ampholytes increased, with triazine ring content from pH 4.2 to 6.1 and showed an aggregation effect toward aqueous suspension of kaolin.

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To pursue amounts and movements of iodine-131 released from the UO₂ pellet to outside and from the pin-holes of fuel rod clad into the primary coolant water of loop, the fission products release experiment was performed by using an artificially pin-holed fuel rod at the in-pile water loop. The specifications of an artificially pin-holed fuel rod were as the following: UO₂ pellet-weight 13.331₅g, content of ²³⁵U0.32 g, diameter 10.63₂mm, height 14.6 6mm; Zircaloy-2 clad-total length 84.9₅ mm, outer diameter 12.21₈mm, thickness 0.69₈mm; Pin-holes located at plenum part, hole diameters 20 μm and 200 μm. An artificially pin-holed fuel rod was irradiated at the JMTR OWL-1. The representative coolant water conditions at the test section in reactor core, in boiling water mode operation, were as follows: coolant water pressure 71kg/cm2 G, coolant water temperature 288°C, steam quality 6∼8%, coolant water flow rate 25 kg/min. The irradiation period of fuel rod at the estimated linear heat rate of 340 Wicm was as long as 21.2 days. The amounts of iodine-131 in the coolant water were determined by gamma ray spectrometry with chemical separation after sampling.
At the end of irradiation, total amounts of iodine-131 released from the artif icially pin-holed fuel rod into the primary loop coolant water came out to be 1.9 Ci. Through the irradiation period, the averaged release rate of iodine-131 was 2.5, μCi/s. A radiochemical m ethod for irradiation examination for nuclear fuel safety was developed by measurement of ¹³¹I released into the coolant water from an artificially pin-holed fuel rod at in-pile water loop. L

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To clarify the effect of variation of coolant water condition on the release behavior of 1-131and Cs-137 from the pin-hole of fuel rod clad, these nuclides in the coolant water were measured at primary loop coolant cool-down and reactor shut-down in the fission products release experiment by using an artificially pin-holded fuel rod at the in-pile water loop. The characteristics of an artificially pin-holed fuel rod were as follows. UO₂ pellet: weight 26.6 g, content of U-235 0.35 g, diameter 13.45 mm, height 17.7 mm. SUS-32 clad: total length 108 mm, outer diameter 15.0 mm, thickness 0.6 mm. Pin-hole located at plenum part of clad, hole diameter 220 μm.
An artificia lly pin-holed fuel rod was irradiated at the JMTR OWL-1. The representative coolant water condition at the test section inlet in reactor core, in boiling water (and pressurized water) mode operation, were as follows: coolant water pressure 71 kg/cm2 G, coolant water temperature 285°C (265°C), coolant water flow rate 25 kg/min (45 kg/min), steam quality 6∼8% (0%). The irradiation period of fuel rod at the estimated linear heat rate of 383 W/cm was 12 days when the primary coolant water was sampled.1-131 in the coolant water was determined by g4mma ray spectrometry with or without chemical separation after sampling. Cs-137, Cr-51, Co-60, Fe, Ni, Cu, and SiO₂ were also determined.
The peaks of 1-131 greater than the averaged release rate revealed themselves at primary loop coolant cool down and reactor shut down. A peak of Cs-137 release rap- greater than the average revealed itself at primary loop coolant cool down. At opening of he experiment, the unique behavior of 1-131 nuclide was ndticed in the primary coolant water, that seemed to be absorbed in crud in coolant water. The specifications of an artificially pin-holed fuel rod were releated to the amounts of 1-131 released from fuel rod into the coolant water, from the results of irradiation examination as described above.

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In order to develop thermostable Raney-type catalysts for the methanation of carbon mono xide, the method of pieparing the Raney-type nickel catalysts was examined. The thermal stabilities of the Ni-Al₂O₃ catalysts depend remarkably on their pretreatment. The thermal stability decreased in the following order: (calcined in air at 550°C)>(calcined in N₂ at 460°C)>(without pretreatment) (Fig.2). For the Ni-Cr₂O₃Al₂O₃ catalysts, the extent of the increase in the Ni crystallite size and the decrease in the amount of H₂ chemisorption during a thermal stability test were found smaller than those by the Ni-Al₂O₃ catalysts (Table 1). The Ni-Cr₂O₃Al₂O₃ catalyst calcined at 550°C was found to be most thermostable of the catalysts tested in this study.

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As a study on the bromine-based thermochemical water decomposition cycles comprising the electrolytic decomposition of aqueous hydrogen bromide, the electric conductivities of the HBr₂-H₂O system were measured in the solutions containing 1∼11 mol kg^-1 of HBr concentration and less than 1.5 mol kg^-1 of Br₂ concentration at 25, 35 and 50°C. The electric conductivities of hydrobromic acid are listed in Table 1, and their variations with HBr concentration and with temperature are shown in Fig.1. The densities of hydrobromic acid, as shown in Fig.2, were also measured at 25°C for the calculation of the relation between the molarity and the molality. The electric conductivities for the ternary system are given in Table 2, The effects of Br₂ concentration on the conductivitis are shown in Fig.3 and in Fig.4.

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Kinetic isotope effect on the dehydration reaction of 2-methyl-3-pheny1-2-propanol (MPP) with anhydrous aluminum bromide was examined. The ratios of the first-order specific rate constants of 2-methyl-d₃-3-phenylpropan-1, 1, 1-d₃-2-ol (MPP-d₆) and of 2-methyl-3-phenylpropan3, 3-d₂-2-ol (MPP-d₂) to that of MPP were k (MPP) (MPP-d₆) = 1.2 and k (MPP) (MPP-d₂) =1.5, respectively. Activation parameters for the d ehydration reaction of MPP-d₂ were found to be E_a= 53.5 kJ/mol, ΔS_??_165.6 J/deg. /mol and ΔG_??_ = 110.4 kJ/mol. The hydrogen bromide-catalyst addition complex is suggested to add to 1, 1-dimethyl-2-phenylethoxyaluminum dibromide to form an unstable intermediate, which then eliminate leaving group-O-AlBr₂.

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The acid-catalyzed amino-Claisen rearrangement of N-prenyl-, N, N-diprenyl-and N-geranylanilines, [1], [2] and [3] respectively, was investigated in detail. Treatment of [1] with ZnCl₂ or AlCl₃ afforded mainly aniline [4], 1, 2, 3, 4-tetrahydro-2, 2-dimethylquinoline [6], 2-prenylaniline [7] and 4-prenylaniline [8]. The use of an excess of the Lewis acids resulted in the selective formation of the cyclyzed compound, [6] or 1, 2, 3, 4-tetrahydro-4, 4dimethylquinoline [5]. On the similar treatment of [3], 2-nerylaniline [14], 2-geranylaniline [15] and their cyclized compound [13] were isolated from the reaction products. The production ratio was extremely dependent on the conditions of the reaction.

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The hydroxylation of methyl salicylate with organic peroxides was investigated. Isobutyl methyl ketone peroxide and acidic solids such as activated clay and diboron trioxide were found to be suitable as the peroxide and the catalyst for this reaction. The main products under theses conditions were methyl 2, 3- and 2, 5-dihydroxybenzoates, in the 2, 3- to 2, 5- product ratio of 0.6∼0.8. In contrast to isobutyl methyl ketone peroxide which gave the methyl dihydroxybenzoates in 65∼69% yield based km the peroxide, hydrogen peroxide (8.0%), t-butyl hydroperoxide (1.4%), and performic acid (12.8%) formed in situ, behaved poorer as an oxidant.

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Substituted benzophenones were obtained by the reaction of benzoyl chloride with some substituted benzenes in the presence of a iron (II) phthalocyanine catalyst. The benzoylation was performed at 160°C for 5 h, and the catalyst was recovered after the reaction. If necessary, the amount of evolved hydrogen chloride was determined by the usual acid-base titration. Iron (II) phthalocyanine 2/100 mol equivalent to benzoyl chloride was sufficient as a catalyst. The substrates with electron-releasing substituents reacted efficiently, while electron-attracting substituents disfavored the reaction. The benzoylation catalyzed by the iron (II) phthalocyanine catalyst is considered as an electrophilic substitution.

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The reaction of acetyl bromide with methyl chloroformate in the presence of a catalytic amount of M(PPh₃)₄ (M=Ni, Pd, and Pt) gave brOmomethane and acetyl chloride accompanied with evolution of carbon dioxide. The reaction was completed within 30 h. The mechanism of this unique reaction was investigated by using acetyl bromide-d₃.

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