In the zone-melting experiment the effective distribution coefficient of azobenzene in naphthalene was determined by the following equation for the eutectic mixtures: (C_x/C_o)=K_e+K_e(x/l), where K_e is the effective distribution coefficient, C_o, the initial solute concentration, C_x, the concentration at a distance x from the top of the sample after a single zone pass, and l, the zone length. The effective distribution coefficient can be obtained either from the slope or from the intercept of the linear plot of C_x/C_o vs. x/l.
The experiments were made on the three samples of naphth alene containing O.2 5, O.5, and 1 wt% of azobenzene at various zone travel rates v, i. e., 0.26, 0.48, 0.70, O.95, and 1.17 cm/h. Also the equilibrium distribution coefficients were determined by the intercept of the linear plot of K_e vs. υ and were found to be 0.0145, 0.0222, and 0.0420, respectively, for the three samples mentioned above.
Thus the resulting values were not zero contrary to expectation for the eutectic system. The mixed cry stal formation within the limited range of the solute concentration was assumed to explain this fact, of which evidence was proved by the solidus curve in the dilute solution, which was determined from the zone melting and thermodynamic theories.

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The Eu²⁺ -actiavted phosphors emitting blue light are widely used in the fluorescence lamp and now attract attention as materials for tunable solid laser in the blue region. The Eu²⁺ ion in fluoride matrices can give a rise to fluorescence from both the 5 d → 4 f and 4 f → 4 f transition. The nature of the emission depends on various factors such as the ionic radius and coordination number of the Eu²⁺ ions, etc.
In this work, we studied the fluorescence properties of Eu²⁺ ions doped in the systems AFAlF₃(A =Na, K, Rb, Cs), for which the 4 f→ 4 f transition was expected according to a simple empirical method to predict the nature of the emission without complex calculations.
The Eu²⁺-doped AF-AlF₃ systems were synthesized by heating the well grou nd mixtures of calculated amounts of EuF₂, AF and AlF₃ at 700∼900°C for 6 h in a N₂-H₂ stream. The fluorescence spectra of the samples showed an intense sharp emission line near 360 nm due to the 4 f⁷(⁶p_7/2)-4 f⁷ (⁸S_7/2) transition along with a weak broad band around 390 nm ascribable to the 4 f⁶5 d-4 f⁷(⁸S_7/2) transition. The emission line was observed to shift to a short wavelength with the decrease in the electronegativity of A. The intensity ratio of the band to the line for Eu2+ ion was larger in NaF-AlF₃ than in RbF-AlF₃. These results are discussed in terms of the nephelauxetic effect and the crystal field. The Mssbauer spectra of the sample showed the presence of Eu³⁺ along with Eu²⁺.

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The high-order structure and internal surface of a porous alunite have been examined by the adsorption of 10 dyes with different charge, size, and shape. The amount of negatively charged monovalent dyes (Orange II and Acid Red 88) adsorbed on the alunite is more than 10, times larger than that of either nonionic molecule (iodine) or positively charged dyes (Methylene Blue and Crystal Violet). The positive charge on the alunite surface is suggested by the calculated residual electrostatic valence and the surface density from acid-base titration. The amount of anionic dyes adsorbed on the alunite decreases with the increase of charge due to the change in effective volume of dye molecule. It is presumed that negatively charged dyes are attracted to the alunite surfaces by hydrogen bonding on the specific adsorption sites. The comparison of the effective molecular size with the apparent area occupied by a dye molecule suggests that the divalent dyes, such as Direct Red 39 and Phthalocyanine Blue, adsorb horizontally on the surface, whereas the momovalent dyes adsorb vertically on the walls of slit-like pores. The synthetic porous alunite seems to be composed of thin layer crystals to form slit-like pores of both 15 and 30Å wide, the latter pore being abundant.

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ZnO catalysts mixed with some other metal oxides were prepared by either a coprecipitation or an impregnation method and their catalytic activity for the methanol decomposition leading to synthesis gas was investigated.
Both ZnO-TiO₂ (mo lar ratio 4 : 5) and ZnO-Al₂O₃ (4 : 5) catalysts were found to be more active than such catalysts as ZnO, TiO₂, Al₂O₃, ZrO₂, and MgO. The ZnO-TiO₂ catalyst coprecipitated from an aqueous ammonia solution showed the maximum activity (total conversion 46 mole %) (Table 1). The formation of Zn₂Ti₃O₈ was observed by X-ray diffraction analysis. High activity was interpreted as due to to high dispersion of ZnO in TiO₂. It was found that the catalytic activity was dependent upon BET surface area of the catalyst and the conversion to methane was closely related to the carbonaceous deposition on the surface (Fig.3). Acti vity of ZnO-Al₂O₃ catalysts prepared from aluminum isopropoxide was comparable to that of the ZnO-TiO₂ catalysts above mentioned. However, it was independent of the surface area, in striking contrast to the ZnO-TiO2 catalysts. It was concluded that the catalytic activity was correlated to the formation of ZnAl₂O₄ (Fig.5). Other r-Al₂O₃'s except for aluminum isopropoxide did not form ZnAl₂O₄.
The activation energy for the d ehydrogenation of methanol did not increase in the ZnO-TiO₂ systems. However, it increased in the ZnO-Al₂O₃ systems. These results probably reflect a difference in the state of ZnO: ZnO is highly dispersed in the former and is covered by Al₂O₃in the latter.

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The poisoning of Ni/SiO₂ catalysts by H2S and ethylene oxide adsorption and the subsequent chemisorption of H₂ at 15°C were described by the method of low field magnetization measurements. When H₂S was introduced on the catalyst, it was estimated by the slope of magnetizationvolume isotherms that one molecule of H₂S dissociatively covered four or five Ni atoms. The bonding number of H₂S with Ni atoms was calculated from the dispersion value of Ni crystallites assuming that the adsorption occured on the top of Ni atoms. It is in good agreement with the result obtained from the assumption of selective attack by H₂S on finer particles of the Ni crystallites on which H₂ adsorption proceeded in the range of small coverage and was shown at the 1st stage in the magnetization-volume isotherm. The result concerning the ethylene oxide adsorption on Ni was similar to those observed for ethylene.The mechanism of ethylene oxide poisoning would be mainly geometrical blocking in a manner equal to the active or inactive sites, whereas H₂S selectively attacked the active sites, finer parts of Ni crystallites, and then transformed these to inactive surface compounds.
The magnetization changes due to the H₂ adsorption on Ni-Cu/SiO₂ were estimated and the influence of Cu addition to the superparamagneitc Ni/SiO₂ composition appeared in the sharp decrease in magnetization changes caused by the initial H₂ adsorption on the bimetallic particles. It seems that the surface composition of the alloy system was different from the bulk one and the surface enrichment in Cu was expected.
The magnetization-volume isotherms for th e adsorption of H₂ and CO were observed at -75and -184°C. H₂ chemisorption was observed as much as 9 ml(NTP)/g-Ni at -184°C and CO adsorption occured at the bonding with Ni atoms in the bridged model and transfered to the single bonding at higher coverage at -75°C.

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The periodic operation effects on the CO-O₂ reaction over Pt, Pd, Rh, Ru and Ir catalysts supported on α-Al₂O₃ were investigated by activity examination, adsorption measurement and evolution pattern analysis. The period of the feed composition fluctuation was varied from O.1 to 20s.
It wa s found that the average reaction rate was significantly increased by injecting CO and O₂ gases periodically and alternately to reactor, compared with the steady state operati on (Figs.2 through 6). The optimum period for the maximum CO conversion increased in the order Ph< Pd=Ru< Pt< Ir (Fig.7) and with a decrease in the temperature and the stoichiometric ratio (2[O₂]/[CO]). However, it was almost independent of the SV and the noble metal loading (Fig.11). The periodic operation, also, improved the light-off temperature (Fig.8).
In the periodic operation, an induction period for CO₂ formation was found to exist in each phase when O₂ was injected onto the CO adsorbed surface (Fig.12). The period was shortened with increasing the temperature (Fig.13) and the O₂ partial pressure (Fig.14). The induction period may be due to the CO desorption and the O₂ adsorption before the surface reaction (Fig.15).
The periodic operation effects mentioned above can be explained in terms of the strong adsorption of CO onto the noble metal surfaces.

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Porphine-porphinatoiron (II) [1] was synthesized from 3, 8, 13, 18-tetramethyl-2, 12-diethylporphine-7, 17-diacetic acid. The complex with imidazole was in a 5-coordinate and high-spin form due to steric effect of the capped porphine. The oxygen adduct of [1] was formed below 0°C, and the life time of the oxygen adduct was longer than that of the corresponding porphinatoiron (II) under the same conditions.

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Complex formation studies of copper-acetate in alcohol-water mixed solution were carried out using the copper ion-selective electrode. Nernstian responses to copper ion concentration at constant ionic strength in methanol, ethanol and 1-propanol (10∼70 wt%)-water mixed solution were obserbed in the range from 10^-2 to 10^-6 moldm^-3 at formal pH range of 4.5-6.3. Copper-acetate complex formation constants in methanol (20, 40 wt%) and ethanol (20, 35 wt%)water mixed solution was determined by measuring the free Cu(II) ion and ligand acetate ion [OAc^-] concentration at constant ionic strength. Acetate ion concentration was calculate d from the pH and acid dissociation constant in those alcohol-water mixed solution. The relation between pCu and p[OAc^-] showed the straight line with slope 2, and the overall formation constant, log β₂, could be evaluated. Overall formation constants of copper-acetate (log β₂) in methanol and ethanol-water mixed solution have shown to be greater (e. g., 3.48in 40 wt% methanol and 3.68 in 35 wt% ethanol) than that in water (2.68) and increased with the decrease of polarity of solvents.

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A flow injection method for uric acid determination was examined. In this method, the hydrogen peroxide generated by injecting a 2μl/ sample into an immobilized uricase reactor is converted to hexacyanoferrate(III) with a peroxidase electrode, in the presence of hexacyanoferrate(II) as a mediator. As the electrode operates at a low potential (ca. -50 mV vs. Ag/Ag⁺), there is little interference from other constituents normally present in serum and urine. A borate buffer (0.1 mol-dm^-3, pH 9.0) containing 0.2 mol. dm^-3 sodium chloride and 1 mmol. dm^-3 potassium hexacyanoferratea (II) served as the carrier solution and was pumped at a constant flow rate of 1.5 ml. min^-1. The peak current was linearly related to the uric acid conce ntration in the, range 0.2∼3 mg⋅dl^-1. The peak width was ca.30 s, and so the determinations could be performed at a 90∼120 samples⋅h^-1 rate with satisfactory precision (1∼-2% R. S. D. ). Results obtained by the proposed method showed excellent agreement with those obtained w ith the Uricase-UV method.

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The sensitivities of electron capture detector (ECD, ⁶³Ni) for various organophosphorus compounds (OPC) were investigated. Minimum detectable amounts of OPCs were measured at. the detector temperatures of 230, 260, 290, 320°C(Table 1). Temperature dependences of electron capture coefficients (K) for OPCs were investigated. The K values of OPCs ordinarily increase with decreasing the detector temperature as shown in Figs.3∼5. Arrhenius plots of KT^3/2 vs.1/T exhibit in positive slopes. These phenomena show that the electron-capture reaction of these compounds proceeds nondissociatively. Electron affinities (EA) were calculated from the magnitude of positive slopes(Table 2). They ranged from 45 to 111 kJmol-1. Relative retention times and heats of solution(ΔH_s) of OPCs were measured (Table 3).ΔHs values ranged from 52 to 67 kJmol^-1.

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A variety of enol esters were prepared by the silver salt-catalyzed reaction of various acetylenic alcohols with carboxylic acids.
It was found that the reactio n was efficiently catalyzed by silver salts (especially silver carbonate: Table 1). Reactions of primaly acetylenic diols and phenylpropargylic alcohols w ith carboxylic acids such as acetic acid and benzoic acid gave the corresponding enol esters in 49∼94% yield (Table 2). Reactions of secondary and tertiary acetylenic alcohols with aceti c acid gave ketones and α, β-unsaturated, ketones in 60∼90% yield (Table 2).
We assumed that these reactions would be promoted by the initial electrop h ilic addition of silver cation to the ethynyl bond and then enol esters are formed by the uncleophilic attack nf earhnxvlate anion.

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The reaction of a-chloro-γ-butyrolactones with alkali-metal halides [lithium chloride, lithium bromide, sodium bromide, lithium iodide, sodium iodide, and potassium iodide] in N, Ndimethylformamide was investigated. Alkali-metal iodides in N, N-dimethylformamide effe c ted the reduction of α-chloro-γ-butyrolactones to the corresponding γ-butyrolactones. Lithium chloride and alkali-metal bromides were not effective. The treatment of several α-chloro-γ-butyrolactones and α-chloro-α-methyl-γ-phenyl-γ-butyrolactone with sodium io d ide in N, N-dimethylformamide yielded the γ-butyrolactones in 68∼84% (GLC). A possible mechan ism of the reduction was discussed.

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The synergistic effect between cobalt(II) acetate (Go(II)) and manganese(II) acetate(Mn (II)) in the liquid phase autoxidation of p-xylene in the presence or absence o f hydrog bromide (HBr) in acetic acid has been studied at 65∼95°C.
The remarkable synergistic effect of Mn(II) was obserbed both in the presence and abser of HBr by replacing about only 1 mol% of Co(II) by Mn(II). Thus the induction period creased, and the oxygen-absorption rate in the chain-propagation step and the total amou of absorbed oxygen increased remarkably. In addition, the concentration of hydroperoxide creased, and the yields of oxidation products such as p-tolualdehyde and p-toluic acid creased. The mechanism of synergistic effect was also discussed.

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In order to disclose the mechanism through which the aroma of odorants solubilized in the surfactant micelle of detergents such as soap, shampoo, etc. is different from that of its original blend, the electric conductivity, transference number and osmotic pressure hate been measured for the dispersed system of sodium dodecyl sulfate (SDS) micelles containing ionone and citral at 30°C. The experimental results showed that the number of micelles in the systern increased in proportion to the amount of added ionone until ionone molecules filled the palisade layer of the mixed micelle. The ionone molecules in excess of their solubility limit in the layer were solubilized into the hydrophobic zone of the micelle. On the other hand, the number of the mixed micelles produced when citral was added into SDS micelle increased to the solubility limit in proportion to the amount of added citral. The partial vapor pressure of these odorants solubilized in SDS micelles was caluculated from the amount of aroma collected by the sweeping method. The aroma intensity of the solubilized odorants was found to increase greatly. Degree of the increase depended on the deviation of their partial vapor pressure in the micelle where the molecular interaction of the odorants was weakened.

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The phenolic sesquiterpene xanthorrhizol [1 a] and its methyl ether [1 b] have been readily cyclized to the substituted ar-himachalenes [ 2 ], which were isomerized to 5- and 7-hydroxycalamenenes or their methyl ethers with an acid catalyst.8-Methoxy-ar-himachalene [2 b], obtained in the above reaction, was presumably formed by cyclodehydration of 6-methy1: 6-(4methoxy-3-methylpheny1)-2-heptanol[ 5 ], therefore, the alcohol 5 was synthesized and its cyclization with an acid catalyst was investigated.
The Grignard reaction of methyl 4-( 4-methoxy-3-methylphenyl)-4-oxobutyrate [10 b] with methylmagnesium iodide yielded 4-methyl-4-(4-methoxy-3-methylphenyl) pentanoic acid [11 a]as a major product.5-Methyl-5-(4-methoxy-3-methylphenyl) hexanoic acid [ 4 ], obtained from the acid [11 a] in 5 steps, was converted to 6-methyl-6-(4-rnethoxy-3-methylpheny1)-2heptanone [6 ], which was a methyl ether of a structural isomer of naturally occurring phenolic sesquiterpene, himasecolone [7 a], a constituent in Cedrus deodara. The ketone [ 6]was reduced with Na131-14to yield the alcohol 5 J. On refluxing with p-toluenesulfonic acid in toluene the alcohol [ 5 ] afforded a mixture of the 1, 2, 3, 4-tetrahydronaphthalene derivatives [22], [23], and [24], having 4-ethyl-7-methoxy-1, 1, 6-trimethyl, 4-ethyl-6-methoxy -1, 1, 7trimethyl, and 4-ethyl-6-methoxy-1, 1, 5-trimethyl as the substituents, respectively.
The intramolecular acylation of the acid [ 4 ] with the Friedel-Crafts catalysts was also investigated.

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Some thermal properties of the polymers obtained by oxidative polymerization of 2, 6-xylenol with manganesea(II) complex catalysts were found to depend on the kind of the ligand of the catalyst, the molar ratio of the ligand to manganese and the polymerization conditions.
These thermal properties contain the decrease of the viscosity of a toluene solution of the resulting polymer by heating at 80°C (Fig.1), the intensity of endothermic peak in the range of 420°C to 480°C in DTA (Fig.3 and 5), and the coloration of the polymer sheet processed under pressure of 100 kg/cm² at 270°C (Table 1, Fig.6). These properties can be improved by treatment with the reagents (PCI₃ and BF₃) also depending on the kinds of the ligand of the catalyst and the ligand ratio (Table 2, and Fig.2 and 4). The observed relationships have been explained to be attributable to the contents of irregular units, quinone ether [2]and quinone acetal [ 3] structures in the resulting polymers. These contents was considered to change with the kinds of ligands, the ligand ratio, and the polymerization conditions.

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2, 6-Dimethylphenol (DMP) was oxidatively polymerized with a copper-pyridine complex in the presence of 2, 2-bis(4-hydroxy-3, 5-dimethylphenyl)propane (BP). The polymerization gave the poly(2, 6-dimethyl-1, 4-phenylene oxide) having phenolic hydroxyl groups on both the chain ends. From kinetics and spectroscopic analyses of the polymerization, the polymerization mechanism has been disclosed as follows: BP preferentially coordinated to the copper catalyst is activated first, and then reacts with the subsequently activated DMP to give the polymer.

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The thermal behaviors of 2-aminoA-methoxy [ 1 ], 2-amino-4-ethoxy [ 2 ] 2-anilino-4methoxy [ 3 ] and 2-anilino-4-ethoxy [ 4 ] 6-isopropenyl-1, 3, 5-triazines were studied by means of differential scanning calorimetry (DSC). For each monomer, an exothermic peak due to thermal polymerization was observed after fusion. The final conversion of the polymerization during DSC measurement was determined from the residual monomer content as measured by UV spectroscopy. The heats of polymerization (ΔH_p) of [ 1 ]-[ 4 ] obtained from the fin al conversion were -14.3, -14.2, -12.3, and -12.2 kcal/mol, respectively. The ceiling temperature (T_e) of [ 1 ]∼[ 4 ], determined as the final temperature of the exothermic peak, were 183, 182, 174, and 174°C, respectively. These ΔH_p and T_e, values are in good agreement with those measured by the equilibrium monomer concentration determined by isothermal DSC. Some monomers formed glassy state when rapid cooled after melting. Thermal behaviors of monomers in the glassy state were also studied and glass transition temperatures of monomers were measured.

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Weatherability of poly(vinyl chloride) (PVC) films containing metal stearates and organotin compounds was siudied by a weathermeter. For all the stabilizers tested, the stabil i zing effect for PVC film!was different between with and without heat treatment prior to irradiation. Photooxidation of PVC film containing metal stearates was accelerated by the heat treatment prior to irradiation. On the other hand, for the samples containing organotin com pounds, the suppressive effect on photooxidation of PVC film was enhanced by heat treatm e nt before irradiation. It was found by means of electron spin resonance (ESR) spectrometry tha t the results depended on radicals which were generated by irradiation after heat treatment. If radical spiecies which generated from stabilizer by irradiation after heat treatment are identica l with radicals which generated by only irradiation without heat treatment and if the co ncentration of the radicals only increased, , suppresive effect of the stabilizer on the photo o xidation was enhanced by heat treatment. The other way, stabilizers which generate ox idized radicals such as alkoxyl and/or peroxyl radical by irradiation after heat treatment accelerate th e photooxidation of PVC.

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A new class of triphenodioxazines containing the phenothiazine ring were synthesized(a). Demethanolation with PhCOCl in PhNO₂ of 2, 5-dichloro-3, 6-bis(10-ethy1-2-inetho-Xy-3-plien04 thiazinylamino)-1, 4-benzoquinone=S, S, S', S'-tetraoxide [7 c] afforded bluish purple. compound 8, 19-dichloro-11, 22-diethyl-bis(1, 4-benzothiazino)[2, 3-b: 2', 3'-m]triphenodioxazine=5, 5, 16, 16-tetraoxide C8b p having a linear structure.
( b ) Ring closure of 2, 5-dichloro-3, 6- bis(10-ethyl-3-phenothiazinylamino)-1, 4-benzoquinone [ 7 aap ] and 2, 5 -dichloro-3, 6-bis(10-ethyl-3-phenothiazinylamino)-1, 4-benzoquinonei S', S'-tetraoxide [ 7 b ]gave two types of compounds, a linear structure a s compound 8, 1 9-di, chloro-11, 22-diethylbis(1, 4-benzothiazino)[2, 3-b: 2', 3'-m]triphenodioxazine [ 8 a] ji and an angular structure as compound 9, 10-dichloro-5, 16-diethylbis(1, 4-benzothiazino)[ 3, 2-c: 3, 2'-n] triphenodioxazine [ 9 b ]. Their colors had purple to bluish green shade. Some. physical tiroperties of [ 8 a ], [ 8 b ] and [ 9 b ] were determined. Especially, [ 9 b ] showed good properties as a pigment for polyethylene materials.

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The autoradiograph reveals a homogeneous deposition of copper as an impurity in the gold electrodeposition from a dicyanoaurate( I ) cyanide solution on the deposition surface. A trace of copper codeposited in the gold deposition increased with the increase in the copper concentration in the bulk and also increased with the increase in the deposition time.

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The polarography of three bis(1, 3-dialkyl-1, 3-propanedionato)nickel(II)complexes, viz., [Ni(acac)₂], [Ni(dppm)₂], and [Ni(dpm)₂], was studied in dimethyl sulfoxide solution c ontaining one of the supporting electrolytes of NaClO₄, TMAP, or TBAP of 0.05 mol⋅dm^-3 in concentration, where acac^-, dppm^-, and dpm^- mean the enolate anions of acetylacetone, d i propionylmethane, and dipivaroylmethane respectively. The polarographic behavior of [NiT(acac)₂] in all the supporting electrolyte solutions and that of [Ni(dppm)₂] and [Ni(dpm)₂] in MAP and TBAP solutions were explained by the electrode reaction given in Scheme 1.
The dissolved state of ten bis(β-diketonato)nickel(II) complexes was related to the properties of their ligands, where seven complexes had been studied by us.

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The resolution of the LiF monochromator was estimated by comparing the X-ray intensity obtained as a result of the energy distribution measurements of the white X-ray reflected by the single crystal of calcite with and without the presence of the monochromator in the path. It was assumed that the profile of the characteristic K_a X-ray of molybdenum emitted from the X-ray tube and, reflected by the calcite crystal, is equal to that of the Compton scattering component, the intensity of which is proportional to the resolution of monochromator. Then, the removability of the Compton scattering component generated at the monochromator was calculated. The data obtained was accurate enough for the practical use in the X-ray diffractometry. It was noticed that the removability of a X-ray tube used for long time was poorer than that of the new one.

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