The electrochemical anion doping-undoping of the film, (C₄H₃N)x, prepared by the electrochemical polymerization of pyrrole was investigated under potentiostatic conditions. The impedance behavior of the doping-undoping process into the (C₄H₃N)x film was measured by the FFT method and it was represented by the Randles-type equivalent circuit. The resistive Rr value sensitively reflected the variation of doping-undoping process of the (C₄H₃N)x film in a similar, manner as in the case of a polyacetylene film, suggesting th at the dopant diffusion process into the polypyrrole film controled the doping process. A. charging-discharging of simple Li-(C₄H₃N)x battery in propylene carbonate was also investigated. The resistive Rr value of the cell clearly had the correlation with open-circuit voltage and the charged conditions.

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Amorphous Gd-Fe thin films were prepared by a vacuum evaporation using a single source containing a mixture of gadolinium and iron. The films have a uniform perpendicular anisotropy. The composition distribution normal to the film was calculated. Suitable conditions for preparing the Gd-Fe thin films were determined.
In order to calculated the composition distributi on in the film, the relationship between the evaporation fraction and the mole ratio of iron to gadolinium in the vapor was discussed using the Raoult's law and the Langmuir's equation. The initial charge of the source was 0.2 g and the initial concentration of iron in the source was 50 mol%. Four kinds of films were prepared at different deposit time. And the composition of these films was measured by EPMA (electron probe microanalyzer). The following results were obtained.
The measured ratio of iron to gadolinium in these films varied from 4.8 to 0.9, as th e evaporation fraction changed from O.07 to 0.32. The calculated values of the ratios were larger than the measured ones, and the average of the differences between the calculated values and the measured ones was 44% of the calculated values.
This corresponds to 59 mol% gadolinium in the film. A perpen dicular magnetic anisotropy was well observed reproducibly in the films which were deposited when convection between iron and gadolinium occured sufficiently in the melt.

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Grain boundaries play an important role in the material transfer in polycrystalline solids. Formerly, the diffusion processes in the solids were analyzed using homogeneous models or the one-dimensional grain boundary model which had been given by Fisher. In this study, we discuss a three-dimensional grain boundary model which represents actual gr ain boundary structure more properly than the conventional models do. Fig.1 shows the schematic of the model and Equations(1)∼(5) represent the diffusion equations for normal grain boundary 1, normal grain boundary 2, parallel grain boundaries, the junctions of these grain boundaries and for the inside of grains, respectively. Equations (6)∼(12) are the boundary conditions. The concentration distributions for the thin film model were calculated using a numerical method with' finite-difference equations. One of the calculated concentration distributions is sho-wrii n Fig.2.
The diffusion species flows rapid ly via grain boundaries and penetrate into grains when the ratio, of the diffusivity in grain to that in grain boundary (D_G/D_B) is less than 10^-3. When this ratio is more than 10^-2, the diffusion profile is similar to that in homogeneous medium which have. no grain boundaries. The concentration near the substrate of the film lowered when the diffusivity in grain increased (Fig.3) or when grain boundary thickness decreased (Fig.4). The concentration diptribu. tion in grain boundary was not largely affected by the number of grains (Fig.5). By comparing the results of three-dimensional grain boundary model with the two-dimensional model, it is known that the grain boundary normal to the film surface largely contributes to increase in the amount of solute content in the film.

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Activated carbon fibers (ACF) were treated with iron salt solutions at suitable temperatures and pH's to precipitate different kinds of iron oxide in order to increase the adsorption activity for NO. The iron-treated ACF samples were examined by the static NO adsorption at 30°C, pulse adsorption of 1 ml NO at 30°C, and flow adsorption from a 300 ppm NO-N₂mixed gas at 100°C. The adsorption isotherms for NO on each iron-treated ACF were of the Langmuir type. The Langmuir b constants were over 0.1 g/g, which were several times larger than the original ACF and commercial activated carbons. The treatment also increased the amounts of both pulse and flow adsorption. In particular, the treatment in similar conditions as that in a formation of α-FeOOH or β-Fe0OH showed the highest NO adsorption activity. The micropore structure of the iron-treated ACF was discussed from nitrogen adsorption. The considerable increase of NO adsorption has been inferred with reference to the micropore change and the amount of iron deposited on the ACF.

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A highly pure colloidal system, composed of metal ultrafine particles and an organic solvent, was produced by means of modified gas evaporation method. This system is free from colloidal stbailizers and is good for the study of the interface of a simple colloidal system. The surface state of metal ultrafine particles dispersed in organic solvents and the dispersibility of the colloids thus prepared were examined as a function of kinds of metal species and solvents. A strong correlation between the state of the colloids and a dipole moment o f a. solvent was found. In a solvent with a large dipole moment, many metal particles were -well-dispersed. On the other hanel, none of metal particles was dispersed in the sol vent with a small dipole moment, resulting in coagulation. This was discussed in connection with the formation of the electric double layer on the surface of metal fine particles. Detailed studise of the dependence of particle dispersibility on the dipole moment of the solvent were made in lead colloidal systems.
Electron spin resonance ( E SR) was detected in the colloidal system of zinc particles in hexane (Zn/hexane) at 3 K. The Lorentzian ESR signal was observed at g=1.97. This line was reasonably attributed to the Zn⁺ ion localized in the surface layer of Zn ultrafine particles but not to the conduction electrons of Zn metal. The ESR signal was affected by the introduction of oxygen gas and it depended both on the type of solvent and on a state of colloid: In the Zn/hexane system, ESR signal disappeared after the introduction of O₂, but not in Zn/1-butanol system, indicating that the magnitude of the dipole moment of the solvents, hexane (0.085 D, 1 D=3.333×10^-30Cm) and 1-butanol (1.50 D), also affects ESR activity.
The ESR absorption intensity as a function of microwave power depended on the average size of the particles. With decreasing the particle size, ESR signal easily saturated at low power. This behavior was explained by the quantum size effect of phonon energy dispersion. When the particle size is reduced, a low energy phonon is cut off and the energy transfer from a spin system to a phonon system is prevented. This means that the longitudinal relaxation time becomes longer for small particles.

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The properties of the silica-coppera(II), -cobalt(II), -nickel(II), -aluminium(III), -iron(III), -chromium(III), -zirconium(IV) and -cerium(IV), prepared by precipitation from h omogeneous solution, and their catalytic activities for the dehydration of 2-propanol were compared with those of the catalysts prepared by usual coprecipitation method. The differencial thermal analysis showed an exothermic peak at 690°C for the coprecipitated silica-copper, and a small exothermic peak at 720°C for the homogeneous silica-copper. Similar thermal behavior was found for the other silica-metals. Infrared absorption at 580 cm^-1 and X-ray diffraction peaks at 2θ=35.5° and 38.5°, which indicate the formation of CuO, appeared at 750°C for the silica-copper, but did not at 600°C. From these results it was found that all the metals were combined with silica gel below about 600°C, but thermal stabilities were higher for the homogeneous catalysts.
Kinetic studies using a flow rea ctor indicated that the dehydration was of first-order reaction and the order of the activities of the homogeneous catalysts was as follows: silica Al>-Ni>-Fe>-Cu>-Zr>-Co>-Cr>-Ce. From the changes in relative activities caused by the addition of KOH and the behavior of pH titration curves for the catalysts, it was concluded that the active site for the dehydration was Lewis acid site and the number of the acid site was larger for the homogeneous catalysts than the coprecipitated catalysts.

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The high-resolution magic-angle-spinning (HRMAS) solid-state 29Si- and 27AI-NMR have been used in the chemical structural analysis of the synthetic zeolites. Y-zeolites (JRC-ZY 4.8 and -Y 5.6), proton-exchanged Y-zeolites (JRC-Z-HY 4.8 and -HY 5.6), mordenites (JRC-Z-M 10, -M 15 and -M 20) and proton-exchanged mordenites (JRC-Z-HM 10, -HM 15and -HM 20) given by the Catalysis Society of Japan have been investigated in this study.²⁹Si-MASNMR has permitted an identification of five distinct Si/Al orderings and the oretical Si/Al ratios on zeolitic frameworks by the computer-deconvolution of ²⁹Si-MASNMR spectra (eg. Fig.1). On the other hand the isotropic chemical shifts from ²⁷Al-MASNMR have revealed the Al-O coordinations in a zeolitic complete framework or in a noncomplete framework.
It was considered that the Si/Al ratios on zeolitic frameworks of Y-zeolites (JRC-Z-Y 4.8and -Y 5.6) have increased during the proton exchange. Especially the chemical ordering of Y-zeolite with low Si/Al ratio (JRC-Z-Y 4.8) by chemical analysis has markedly changed (Fig.2, Tables 1 and 2). This behavior has been more appreciably observed in the "AlMASNMR spectra (Fig.3, Table 3). These results have suggested that the dealumination from the zeolitic frameworks of Y-zeolites has taken place though the -Si-O- bondings have been remained.
On the other hand, with regard to the mordenites (JRC-Z-M 10, -M 15 and -M 20), no appreciable change in the Si/Al configurations on zeolitic frameworks have been spectrally observed during the proton exchange (Figs.5 and 6, Tables 4, 5 and 6). In addition, the crystallinities and some distinct tetrahedral locati ons in the Si(OAl)_n(OSi)_4-n environments of Y-zeolities and mordenites have been discussed. t Characterization of Zeolites. I.

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Thermal decompositioonf electrolyte cobalt(III) complexes[Co(Hdmg)₂B₂]X and nonelectrolyte cobalt(III) complexes[CoX(Hdmg)₂B]n the solid state was studied by thermogravimetry(TG) and differential thermal analysis(DTA), where H2dmg is dimethylglyoxime, B is aniline and its derivatives, and X is Cl, Br, I, SCN, NO₂, NO₃, or ClO₄ ion. In the case of the electrolyte complexes[Co(Hdmg)₂B₂]Xan, endothermicp henomenond ue to the replacement of the axial ligand (base B) by the outer-sphere anion (X) was observed and the formationo f [CoX(Hdmg)₂B] as confirmed.
The observationo f the endothermicp he nomenonr evealed that the replacementr eaction temperature depends on the basicity of axial base in the case of the chloride complexes [Co(Hdmg)₂B₂]Cl. On. the other hand, in the case of the nonelectrolytec omple xesh aving no outer-spherea nion such as [CoX(Hdmg)₂B] and analogousn onelectrolyte Fe(II), Ni(II) and Cu(II) complexesa n exothermicp henomenonw as observed. When solid NH₄Cl was addedt o the electrolytec hloridec omplexes[Co(Hdmg)₂B₂]Cl a, new green compoundw as formed as the secondr eplacementp roduct, and two endothermicp eaks were observe di n the DTA curve of the complex. The electronic and infrared spectra of the green compound suggest that the constitutional formula is H[CoCl₂(Hdrng)₂].

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The dimerization of diaqua(ethylenediamine)platinum(II) (DAEP) was investigated by means of ion-pair high-performance liquid chromatography. The experiments were carried out under the conditions of pH 2.50∼10.00 at an ionic strength of μ=0.01 containing 2.5×10^-3 mol⋅dm-3 of DAEP. The optimum HPLC conditions were as follows: column, Nucleosile 5 C18 (4.6 mm in diameter, 15 cm in length); eluent, acetonitrile: 0.1 mol⋅dm^-3 tartaric acid: sodium dodecyl sulfate =100 cm³: 100 cm³: 0.5 g; flow rate, 0.91 cm³⋅min^-1; detection, UV 260 nm. Two peaks appeared in the chromatograms, in which one peak (a)corresponded to DAEP. As the dimerization proceeded, another peak (b) corresponding to μ-p-hydroxo-bis[ethylenediamineplatinum(II)](D²⁺) appeared and grew gradually, while peak (a) fell down. After the equilibrium was attained, the ratio of the peak height of (a) to (b) was constant. The dimerization proceeded in the range of pH 4.90∼8.50, where DAEP, aqua(ethylenediamine)hydroxoplatinum(II) (AEHP) and ethylenediaminedihydroxoplatinum(II) (EDHP) were present. However, no dimerization occurred in lower or higher pH ranges, in which AEHP was in a negligible amount. Thus, the dimerization was found to proceed by the following equations.

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We have previously reported on the effects of carbon black for the direct determination of metal oxides such as beryllium oxide, etc., which have high atomization temperatures on atomic absorption spectrometry.
This paper deals wit h the effects of carbon black for the direct and absolute determination of the solid samples of aluminum fluoride and aluminum phosphate ground to tiny powder (about 1.6 pm particle size), by means of flameless AAS. And then, aluminum in cryolite was determined by this method as practical analysis.
It has been observed that the aluminum absorbance was increased about 2.4 times by addition of about 1 wfv% carbon black to aluminum fluoride containing 1 ppm aluminum and about 1.7 times increasing was obtained in the case of aluminum phosphate. From X-ray diffraction and thermodynamic considerations, it appears that the carbon black led to a rapid decomposition of the salt and formation of oxide on the ashing step.
The detection limit was about 1×10^-9g⋅ml^-1, and the coefficient of variation of a luminum fluoride (containing aluminum of 1 ppm) was 5.1% (5 times determination).

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Carboxymethyl Sephadex C-25 was converted to (2-aminoethylcarbamoylmethyl)Sephadex(ED-Sephadex) by the reaction with ethylenediamine-ethanol solution at 100°C. Then, ED-Sephadex was allowed to react with carbon disulfide in triethylamine-ethanol solution at 80°C to get [2-(dithiocarboxyamino)ethylcarbamoylmethyl]Sephadex(DE-Sephadex). Mercury(II), copper(II), lead(II), cadmium(II), zinc(II), nickel(II) and manganese(II) ions could be quantitatively collected from 50 ml of 1×10^-5 mol⋅l^-1 solution of each metal salt over the pH range of 0.6∼9.9, 0.6∼9.7, 2.7∼6.0, 3.4∼9.1, 5, 0∼9.6, 5.1∼8.8 and 5.8∼8.3, respectively, by stirring with O.1 g of DE-Sephadex for 30 minat room temperature.. Collection of each metal ion from 1 mol⋅l^-1 solution of sodium nitrate, sodium chloride or sodium bromide was quantitative. Collection of mercury and copper ions from 1×10^-1 mol⋅l^-1 EDTA solution was quantitative but collection of other metal ions was incomplete. Each metal ion except for mercury ion could also be quantitatively collected from 500 ml of 1×10^-8mol⋅l^-1 metal ion solution by passing the solution through the column packed with O.3 g of DE-Sephadex or by batch method with O.1 g of DE-Sephadex, and could be recovered from the DE-Sephadex by eluting with diluted nitric acid or by dissolving the DE-Sephadex with concentrated nitric acid or a mixture of 30% hydrogen peroxide solution (O.5 ml)and 18 mol⋅l^-1 sulfuric acid (2 ml) by heating. The separation of copper ion from manganese ion was carried out as follows. Copper ion was collected from 500 ml of sample solution containing 5.00×10^-4 mmol each of both metal ions by batch method with O.1 g of DESephadex at pH 1.7 and manganese ion was collected with another fresh DE-Sephadex from the mother liquor after readjusting to pH 7.7. The separation of copper ion from other metal ions such as nickel, zinc, cadmium and lead ions was also achieved by the similar procedure.

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Conductometric titration of organic halides such as benzyl chloride, benzoyl chloride and hydrogen chloride with EDTA were investigated in N, N-dimethylformamide(DMF). The observed molar ratio between these chlorides and EDTA was 1: 1.
The use of other solvents (DMSO, pyridine, etc.) did not give significant inflection points. Less than 1 v/v% of water gave no influence on this method, but the existence of chloride and metal ions gave positive error. The applicable concentration range of the method was about from 1×10^-3mol⋅dm^-3 to 5×10^-2mol⋅dm^-3
It seemed that the reaction was dependent on bond dissociation energy between carbon and halogen atoms in halides and could be titrated when this energy was less than about 3×10^-2 kJ⋅mol^-1.
The propo sed method can be applied to analysis of halides in oils.

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The cis-trans-isomerism of the protonated ring-substituted acetanilides in CF₃COOH has been investigated by measurements of the intensity ratio of the methyl signals in acetylamino groups in their ¹H-NMR spectra at 30°C. Consequently, the acetanilides with an electrondonative group and monohaloacetanilides (Group I) showed the cis-trans-isomerism, and their equilibrium ratios (EIZ) were found to be about 1/4∼1/7 in CF₃COOH. And then, the acetanilides with nitro group as an electron-attractive group (Group II) showed only Z-form. In the cases of 2, 6-dihaloacetanilides (Group III), both E- and Z-isomers were observed, whose E/Z ratios were obtained to be about 1/3∼1/5 in CF₃COOH. Furthermore, the activation parameters of the equilibrium between E- and Z-forms in Group III were obtained by the line-shape analysis of their DNMR spectra in CDC₃ or CF₃COOH (e. g., 2, 6-dichloroacetanilide [1n] _??_=68.1 kJ/mol, _??_=63.5 kJimol; K (E/Z)=1/7 in CDCl₃ at 25°).

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The reactions of p-toluenesulfonyl chloride [1a] and bromide [1b] with various tertiary amines in benzene were investigated.1-Methylpyrrolidine [6] gave N-(4-halobuty1)-Nmethylp-toluenesulfonamides [8] in good yields; the bromide [8b] was obtained in a better yield than the chloride [8a] under similar reaction conditions (Table 2, Scheme 2).1Methyl- and 1-ethylpiperidines ([7a] and [7b]) were far less reactive with [1] and the reactions took place appreciably only at a very high concentration of the reactants to give two types of sulfonamides. The major product was 1-(p-tolylsulfonyl)piperidine [11] and the minor one was N-(5-halopentyl)-N-methyl-p-toluenesulfonamide [10] in the reaction of [7a] with [1] (Table 2, Scheme 3).2-Benzylquinuclidine [16], nicotine [20], and 1-methyl-L-proline methyl ester [27] were also less reactive than [6] or -quinuclidine, but in the reactions using a very high concentration sulfonamides were effectively obtained (Table 3). 2-Benzylquinuclidine [16] gave 2-benzyl-4-(2-chloroethyl)-1-(p-tolylsulfony)piperidine [17a] and a small amount of 4-(3-phenyl-2-propeny1)-1-(p-tolylsulfonyl)piperidine [19], which may be formed by the elim ination of hydrogen chloride from 4-(3-pheny1-2chloropropy1)-1-(p-tolylsulfonyl) piperidine [1/a]. The reaction of [16] with [1b] gave only [17b] as an isolated product (Table 3, Scheme 3). The reaction of[20] gave N[4-chloro-4-(3-pyridy)butyl]-N-methyl-p-toluenesulfonamide [22a] and N-[4-(3-pyridy1)3-buteny1]-N-methyl-p-toluenesulfonamide [23] (Scheme 4). The reaction of [27] with [1a] gave N-[4-cliloro-1-(methoxycarbonyl) butyl]-N-methyl-p-toluenesulfonamide [28a](Scheme 6). The reaction of [20] or [27] with [1b] gave [22v] and [23] or [28b] and [29b], respectively, in better yields than those with [1a](Table 3, Schme 4, 6). The products [22a], [22b], [29a] and [29b], which were produced by the C-N cleavege reaction between the asymmetric carbon and nitrogen, were racemic but the products obtained by the cleavege of the C-N bond of the other side retained optical activities. t The Reaction of Tertiary Amines with Electrophilic Reagents. III.

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Kinetic study on the pyrolysis of 2-(N-tosylalkanesulfinimidoyl)pryridine 1-oxides [1] was carried out. The behavior of the pyrolysis of[1] differed markedly from that of S-pheny lS-ethyl-N-tosylsulfimide [2], suggesting that the pyrolysis of [1] proceeds vi a a fivemembered transition state. The activation entropy of [1] in benzene was nearly zero, w hich is considerably larger than that of [2] (-24∼-36J⋅ K^-1⋅mol^-1). Primary kinetic is otope effect on the pyrolysis of [1] was found to be nearly 5. This value is about two times larger than that of [2] (2.9). Furtker, ethanol retarded completely the pyrolysis of [2] under usual reaction conditions, whereas the pyrolysis of [1] under the same condition s was retarded only a little as the specific rate of the pyrolysis was about half o f that in benzene as an aprotic solvent. From the results obtained, a mechanism of the elimination reaction of [1] was discussed.

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Catalytic effects of activated carbon on degradation of polypropylene were investigated at 477∼526°C by using a fixed-bed flow system. The catalyst was effective for the C-C bond scission of the chain and the dehydrocyclization of the aliphatic fragments with relatively low molecular weight. The degradation products obtained at 502°C and with the contact time of 35.0 g-cat⋅min/g-PP were distributed among C₁∼C₁₂ fractions and contained 20 wt% of aromatics. The amount of aromatics, of which the main components were m-xylene and 1, 3, 5-trimethylbenzene, corresponded to about two-thirds of that formed in degradation of polyethylene over activated carbon. Therefore, it was evident that the dehydrocyclization was difficult to occur in degradation of polypropylene, compared with the case of polyethylene. The degradation reaction over activated carbon seems to be initiated primarily by the abstraction of hydrogen atom bound at tertiary carbon on the catalyst surface.

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Five 6-(normal alkyl)-4-chlorophenol-2-surfonates (alkyl; n-C₆H₁₃, n-C₈H₁₇, n-C₁₀H₂₁, n-C₁₂H₂₅ and n-C₁₄H₂₉) were synthesized and identified by elemental and spectroscopic analyses. Surface active and antimicrobial properties of these compounds were investigated. The results are as follows:
1) Surface activity (surface tension, emulsifying, dispersing, and solubilizing power)increased with increasing alkyl-chain length up to n-C₁₂H₂₅ and then decreased in the n-C₁₄H₂₉ drivative.
2) These sulfonates were screened for antimicrobial properties with gram-positive and gram-negative bacteria, and fungi. It was found that the n-C₁₀H₂₁ derivative had activity comparable to that of the control sample PCP.

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Induced circular dichroism (ICD) of azo dye with cationic biopolymers have been studied. Many factors such as pH and residue/dye ratio influence the ICD of such systems. As an additional factor, thermal changes in the chiral complexes of three kinds of poyl(L-lysine)homologs with Methyl Orange (MO) are examined by means of ICD. The magnitudes of ICD of the three complexes increased when the temperature of the systems was lowered, and decreased when raised. Although the spectral changes of MO and the conformations of the three polypeptide-MO complexes were thermally reversible, the behaviors of the ICD spectra of the individual complexes were more sensitive to temperature change and inverted the sign of ICD with shortening the side-chain length. Among the three complexes, the ICD spectra of the poly(L-ornithine)-MO complex were almost thermally reversible. The results were discussed from the standpoints of the side-chain length, and the distance and dihedral angle between dye chromophores.

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Poly(1, 3, 4-oxadiazole-2, 5-diyl-1, 4-phenyleneiminocarbonyl-1, 3-phenylenecarbonylimino-1, 4-phenylene) was prepared by a low-temperature solution polycondensation using N, Ndimethylacetamide as an organic solvent.
It was difficult to enhance the mechanical properties of these polymer films by cold and heat drawing. Therefore, the films were drawn in a N, N-dimethylformamide/H₂O mixture (60: 40, v/v) at 60°C and then heat-treated under a tension. The values of the Young's modulus and the strength at break of 3-fold drawn and heat-treated films (sample [7])were 13.0×10¹⁰ dyn/cm2 and 54.9 kg/mm2, respectively. These values are about 10.8 and 9.0 times as large as those of undrawn films. The values of the Young's modulus and the strength at break were decreased to 10.7×10¹⁰dyn/cm2 and 39.5 kg/mm2 after 2 hoursheataging at 350°C in air. This result showed the high-temperature durability of the drawn and heat-treated materials.

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Cyano(2, 2'-bipyridyl)cobalt(II) complex (Co/CN/bpy ratio=1: 1: 1) initiated the polymerization of methyl methacrylate (MMA) in an aqueous solution containing a surfact ant under hydrogen atmosphere. Since the polymerization of MMA proceeds only under hydrogen atmosphere, the hydride of the above complex is the initiator.2, 2'-Diphenyl-l-picryhyd razyl inhibited the polymerization. The copolymer composition curve for the copolymerization of MMA with styrene by this initiator was similar to that for the ordinary radical copolymerization. Thus, it is considered that the polymerization of MMA by this in itiator proceeded throught a radical mechanism. The effective surfactants were nonionic Tween and Brij types.

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In spite of the efforts of many investigators, the solvent effects on the rates of unimolecular decompositions for a wide variety of peroxides and azo compounds are still not evaluated enough. This paper describes the effects of monosubstituted benzenes(I) and normal alkanes 00 on the rates of thermal decomposition of“dicumyl peroxide”(bis(1-methyl-1-phenylethyl)peroxide) (DCP) at 120∼140°C and also those of (II) on, the rates of photodecomposition at 25°C.
The both decomposition rates of DCP in these solvents were the first order over the range of the concentrations from 10^-3 to 10^-2 molii. The rate constants (k_d) changed in these solvents. The k_d in benzonitrile was greater than that in tetradecane by a facto r of 3.2 at 120°. In (I), k_d was related to the dielectric constant, and/or E_T valu e of each solvent and the activation entropy obtained decreased as the polarity of solvent i n creased. In (II), the straight line with a positive slope was shown between k_d and th e reciprocal of viscosity and was also observed by the use of the Pryor's equation on viscos i ty dependence. However, the k_d in (I) was independent of the solvent viscosity. On the basis of these results, it has been found that the rates of decomposition of DCP in (I)increase with an increase in the solvent polarity, while those in nonpolar solvent (II) decreas e with an increase in the solvent viscosity.
The Pryor's equation and a v a lue in it were examined. The equation with 1/2 of a could be applied to (II) regardless of different decomposition temperatures, but the application to (I) remains obscure as the a value was undecided yet.

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The degree of dissociation of polyelectrolytes and their conformation are appreciably influenced by the hydrogen ion concentration. On this point of view, polyelectrolyte complexes (PEC) by mixing methyl glycol chitosan (MGC) with the mixture of (carboxymethyl)dextran (CMD) and poly(vinyl sulfate) (PVSK) were prepared at various concentrations of hydrogen ion and in different order of mixing.
As a result of the experiment, many kinds of PEC were prepared and these are classified into three groups by means of elemental analysis, IR spectroscopy, colorimetric reactions with toluidin blue and solubilities of PEC. The first group was PEC prepared in a concentrated acidic solution, which were composed of MGC and PVSK connected by the ionic bonding with each other. The second group is PEC formed in the solution of higher pH, which were made up of MGC, CMD and PVSK linked by the ionic bonding with one another. The last is the group in the solution of lower pH, which were also constituted MGC, CMD and PVSK, and had more complex three dimentional network structure.
It is possible to cast PEC into membranes with a ternary solvent system (HCH, 4-dioxane-water), and it is revealed that uniform and translucent membranes were obtained from all kinds of PEC.

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Diazonium hexafluorophosphate (Diazonium PF₆ salt) is virtually water-insoluble diazonium salt. Coupling reactivity and photolysis characteristics of four kinds of diazonium PF₆ salts were investigated. Coupling rate constant (k_c) in acetonitrile with N-(3-morpholinopropyl)3-hydroxy-2-naphthalenecarboxamide (coupler: No.5) increased with increasing infrared absorption frequency for the N-N stretching mode (ν(_-N2)) of the diazonium salts. This relationship was similar to that observed in an aqueous medium. The solubility in water of diazonium PF₆ salt was 1∼4×10^-4 mol⋅dm^-3: about one tenth of that of diazonium tetrafluoroborate (Diazonium BF₄ salt). The photolysis rate constant (k_p) in the film specimen containing diazonium PF₆ salts was obtained using UV fluorescent lamp as a light source. The k_p decreased with increasing the vν(_-N2), in contrast to the case of k_c. Self-catalysis effect was found in the coupler No.5. The coupler reacted with diazonium PF₆ salts in acetonitrile without the addition of base. It is suggested that the c oupler is in the naphtholate ion state in acetonitrile via intramolecular proton-transfer process.

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The growth of niobium nitride(NbN) whiskers on various substrates from the NbCl₄N₂-H₂ system was investigated in the temperature range of 900∼1400°C, and the superconducting transition temperature (T_c) of the whiskers was measured. Ni/graphite, (Pd +Si)/mullite, and Pd/quartz were effective for the growth of NbN whiskers. In the growth on Ni/graphite substrate, pillar or needle whiskers grew with the maximum axial growth rate of ca.1 mm/h. The tip of pillar whiskers were surrounded with facets, while the tip of a needle whisker was semisphere which contained Ni. Needle whiskers are considered to grow by the VLS mechanism. Besides NbN whiskers, NbN_xC_1-x whiskers grew on Ni/graphite. In the case of a Pd/quartz substrate, pillar niobium nitride whiskers grew, the phases and growth rates of which changed with the gas vapor compositions. With a composition [NbCl₄]=1.0∼1.5 vol%, [N₂]=30∼70 vol%, and [H₂] =10 vol%, the deposit was a pure δ-NbN phase. The axial growth rates showed a maximum for [NbCl₄] or [H₂]. The T_c of the whisker grown on Pd/quartz was 15.3 K, while the whisker grown on Ni/graphite showed two-step transitions at ca.15 K and 17.3 K.

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The volatilization rates of trichloroethylene, 1, 1, 1-trichloroethane, tetrachloroethylene, as well as oxygen were measured by a photoionization detector. The gas-phase concentration of these chlorinated organics volatilized from aqueous phase was continuously monitored. The use of the photoionization detector enabled the faster and easier determination of the volatilization rate, compared with the conventional method. It was concluded that the volatilization rates were controlled by mass transfer in the aqueous phase. The ratio of the volatilization rate constant of the chlorinated organic (i) to that of oxygen, K_v⁽ⁱ⁾/K_v^O2, was 0.61±0.03 for trichloroethylene and tetrachloroethylene, and 0.59±0.03 for 1, 1, 1trichloroethane, respectively.

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The chemical composition of fatty acids, carbohydrates, pigments, and amino acids in the red tide phytoplankton (Chattonella antiqua, Chattonella marina, Heterosigma akashiwo, Gymnodinium nelsoni, Gymnodinium nagasaki) from Seto Inland Sea was analyzed by means of gas chromatography and mass spectrometry, gas chromatography, and high performace liquid chromatography. It was found that fatty acids (C₂₀-unsaturated fatty acid), carbohydrates (water-extractable), amino acids (L-histidine) and pigments (fucoxanthin, peridinine), were the most important organic compounds identified in the red tide phytoplankton.

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The Knoevenagel condensation of p-nitrophenylacetic acid [1] with m-nitrobenzaldehyde [2] was carried out in the presence of amines such as piperidine, diethylamine, triethylamine, pyrrolidine, morpholine, N-ethylmorpholine, etc. trans-3, 4'-Dinitrostilbene [3], 1-(m-nitrophenyl)-2-(p-nitrophenyl)ethanol [4], and α-(p-nitrophenyl)-m-nitrocinnamic acid [5] were isolated. The {[3]+[5]}/[4] ratio varied greatly with the amine used, because of its steric hindrance. [3] also was obtained by the dehydration of [4] with small amounts of concentrated sulfuric acid in 96% yield and by the decarboxylation of [5] with pyrrolidine in 90% yield. A probable reaction pathway was discussed.

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A new sulfide crystal, KHgSbS₃, was synthesized by hydrothermal heating of the powder mixture of Sb₂S₃ and HgS in the solution of KOH/K₂S(=1/5) at 180°C for 50 h in a Pyrex glass tube. The single rystal has tabular shape and the color is reddish orange. It belongs to monoclinic structure and space group is A 2/a or Aa. The lattice parameters determined from four-circle diffractometer are a = 17.0 84(8)Å, b=8.647(4)Å, c =8.951(3)Å, β=105.78(5)°. The indexed X-ray powder diffraction data were obtained from GuinierHägg camera method; the five strongest lines are [d(1)(hk1)]: [3.391(80)(320)], [3.112(100)(122)] [3.0 59(100 b)(222)]1, [2.2 38(90)(204)] [2.144(80)(140)].

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A simple and rapid method was presented for the determination of acetylcholine and choline, using the high-performance liquid chromatographic system with enzyme electrodes as the electrochemical detector. The enzyme electrode was made up of cross-linking acetylcholinesterase (AChE) and choline oxidase (ChO) with bovine serum albumin (BSA) or AChE, ChO and peroxidase (POD) with BSA using glutaraldehyde on a platinum electrode silanized with (3-aminopropyl)triethoxysilane. The AChE-ChO and AChE-ChO-POD electrodes were based on the amperometric detection of hydrogen peroxide and hexacyanoferrate(III)generated by the enzymic reactions, respectively. The method was high-sensitive and specific for the determination of acetylcholine and choline. The detection limit was 1.5pmol for choline and 2.9 pmol for acetylcholine. The enzyme electrodes could be used continuously for at least 20 d.

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The iron(III) chloride-catalyzed reaction of benzylidene dichlorides with hexamethyldisiloxane was found to give benzaldehydes in good isolated yields of 65∼74%. Isophthalaldehyde was also given from the reaction of a, a, a', a'-tetrachloro-m-xylene with siloxane in 40% yield. From the reaction of diphenyldichloromethane benzophenone was obtained i n 78% yield. A plausible pathway leading to aldehyde is presented.

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3 H-Phenoselenazin-3-ones [7a, b] pobtained by condensation of 2, 5-dichlorobenzoquinone or chloranil with a zinc salt of 2-animobenzeneselenol [4] are valuable intermediates for preparation of new classes of phenoselenazines.
For example, the reaction of 1, 2, 4-trichloro-3 H-phenoselenazin-3-one [7 b] with [4] gave 6, 13-dichlorophenoselenazine [9 b] in AcOH, whereas it afforded bis(benzoselenazino)selenazine [12] in DMF.
On the other han d, a similar reaction of [7 b] with a zinc salt of 2-aminobenzenethiol [5] in AcOH formed 6, 13-dichloro[1, 4]benzoselenazino[2, 3-b]phenothiazin e [10 b]. The streak colors of [9 b], [12] and [10 b] were from purple to violet, and their melting points were above 300°C (by DTA). The absorption maxima of visible spectra in DMF were found in the narrow range of 563∼578 nm.

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Various conjugated unsaturated compounds were treated with 1, 1'-bis(methoxycarbonyl)divinylamine under photoirradiation. Whereas the reagents [2]∼[8] gave no cycloadducts, the reaction with (E, E)-2, 4-hexadienedioate [9], (Z, Z)-2, 4-hexadienedioate [10] and (E)2-hexen-4-ynedioate [11] afforded 1:1-adduct, novel 7-azabicyclo[2.2.1]heptanes [12], [13]and [14], respectively. Spectral analyses of the products [12]∼[14] showed that the addition proceeded stereoselectively, retaining the original configuration of the reagents, and the addition occurred preferentially on the carbon-carbon double bond in the case with the reagent[11].
It can be said, as a result, that the reactivity of these conjugated unsaturated re agents is similar to that of substituted ethylenic compounds which we have already reported in our previous paper.

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Several phenolic compounds were isolated from the leaves of Rabdosia japonica (BURM. )HARA. Their structures were identified as rutin, isoquercitrin, pedalitin, and rosmarinic acid by comparison of their spectroscopic data with those of the authentic samples. Methyl rosmarinate was found also in Rabdosia japonica and Rabdosia japonica

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Syntheses of several N-octadecylsquarylium dyes were studied in order to improve their preparation so far in use. In one typical run, a mixture of 1-octadecyl-2, 3, 3-trimethyl-3H-indolium p-chlorobenzenesulfonate (2 mol) and squaric acid (1 mol) was refluxed in 1pentanolchlorobenzene (3: 2 vol.) for 24 h to form the bluish green dye. In another typical run, the above mixture was heated at 160°C for 5 h in the presence of Nafion-H catalyst. Yield of the squarylium dye obtained by the second method was better than that by the first method.
The analogous s quarylium dyes were also produced by using N-octadecyl intermediates derived from 2-methylbenzoselenazole, 2-methylbenzothiazole, N-methylaniline and Nmethylm-toluidine according to those two methods.

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