In order to make clear (1) the existence of the monomers and dimers of 3- and 5-methylpyrazoles in CC14s olution, and (2) the formation of 3- and 5-methylpyrazoleacetic acid complexes and 3 ( 5) methylpyrazolium acetate in the 3-methylpyrazoleacetic acid system in the ground state, the ab initio molecular orbital calculation and the IR measurements were carried out.
From these results the following conclusions were drawn: (1) In the IR spectrum of 3-methylpyrazole in CCl₄ solution, the bands at 3480 and 3470 cm^-1 were assigned to the N-H stretching band of the monomers of 3- and 5-methylpyrazoles, respectively, and the strong and broad bands at 3200 and 2980cm^-1 were assigned to the N-H stretching vibrations (B_U) of the dimers of 3- and 5-methylpyrazo les, respectively. (2) In the ground state the calculated stabilization energies for the models of the 3-methylpyrazoleformic acid and 5-methylpyrazoleformic acid complexes are 80.20 and 80.62 kJ mol^-1, respectively. The magnitudes of these values suggest the possibility of the formation of the hydrogen bond complexes (abbrev.: H-bond complex) between 3- and 5-methylpyrazoles and acetic acid. (3)The calculated stabilization energy of the 3- or 5-methylpyrazolium formate is 51.44 kJ mol^-1. Although the magnitude of the stabilization energy is smaller than those of the H-bond complexes, it suggests the possibility of the formation of 3- or 5-methylpyrazolium acetate (abbrev.: cation complex)through the proton-transfer process. (4) Experimentally, the characteristic bands ascribed to the Hbond complexes and the cation complex were observed in the region from 3500 to 1300 cm^-1 of the IR spectrum of the 3-methylpyrazoleacetic acid system. The bands at 3280 and 2540 cm^-1 were assigned to the N-H and O-H stretching vibrations of the H-bond complexes, respectively. The bands at 1900 and 1360 cm^-1 were assigned to the N-H stretching vibration and the inplane bending vibration of the N-H bonds of the cation complex, respectively. (5) The good linear relationship exists between the N-H stretching vibrational frequencies (ν^c)o f the optimized models of 3-methylpyrazole and its relat ed compounds used for the present calculation and their N-H bond distances.

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111-NMR, X-ray photoelectron, and electronic absorption spectra have been measured for two kinds of complexes, monomer troNi. ( II ) and dimer (troNi (II))₂. which are formed between tropolone and nickel ( II ). From these spectral data together with MO calculations using a modified Pariser-Parr Pople approximation, the electronic and molecular structure of the above complexes has been clarified. In the solid state, the central metal ion of troNi( II ) takes a tetrahedral sp³ hybridization. On the other hand, in solution, the metal ion takes an octahedral d²sp³ hybridization, being linked with solvent or water (contained in the solvent) molecules. Furthermore in solution, the two tropolonato skeletal planes are coplanar, and are arranged transoid. The 402, 339 and 240.2 nm bands of troNi ( II ) observed in ethanol are assigned to the calculated ππ², ππ² and ire transitions, respectively. A weak band observed at around 674 nm is due to d-d transitions. The XPS Ni^2p band of troNi ( II ) is observed at 857.8eV, and that of (troNi(II))² at 858 eV. Both bands accompany with shake-up bands, indicating that the two complexes are paramagnetic in the solid states.

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Calcium molybdate film crystals doped with neodymium (CaMoO₄: Nd) were grown from an Na2MoO₄ flux by a liquid phase epitaxial method. The growth was conducted by immersing CaMoO₄ s ubstrate crystals (about 3 mm×3 mm) in the high-temperature solutions (1000°C) of CaMoO₄ (28.5mol%)-Na₂MoO₄ (71.5 mol%) containing a small amount of Nd₂O₃ for 8 h, and subsequent coolin g to 950, 900 or 850°C at a rate of 6°Ch^-1. Pale purple and transparent CaMoO₄: Nd film crystals were homoepitaxially grown on the substrate crystals. The grown crystals were up to about 58μm in thickness depending upon the slow cooling range. The indices of the well-developed faces were [112]. Neodymium was homogeneously incorporated in the film crystals. Sodium from the flux was also incorporated in the crystals.

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[2, 3]-Wittig rearrangement is one of the powerful tools for carbon-carbon bond forming reaction (Chart 1). In this paper, ab initio MO calculation was performed to locate the type I (Rautenstrach)and II (Trost) transition structures for [2, 3]-Wittig rearrangement of cis- and trans olefin (1 and 2, respectively), in which Li atom is coordinated with CH₃OCH₃ molecules as the model for the coordination of etheral solvents commonly used in experiments, and obtained the new insight to the solvent effect attributable to the observed stereochemistry. Transition structures were located at the RHF/321G basis set and energies are evaluated by using density functional theory (Becke3LYP/3-21(+)G level//RHF/3-21G).
The results of this study were summarized as follows.
(1) Salvation by three CH₃OCH₃ molecules are p ossible only for the Rautenstrach's type transition geometries ( I ), because of larger coordination space of solvent molecules around Li atom than that of Trost's type envelop ( II ).
(2) Coulomb interaction between growing negative charge on C4 and Li cation in Trost's type transition structures ( II ) could be maintained even by the coordination of two oxygen atoms of the solvent molecules to Li atom, indicating that the stabilization of growing anion on C4 by this contact is considerably large.
(3 ) The energy difference between each transition structure leading to the major and minor stereoisomeric products became smaller as the number of coordinating solvent molecules to Li atom increases.
This study shows that the stereoselectivity of [2, 3]-Wittig rearrangement is controlled und er the involvement of the solvent molecules in transition state and comprehensive, self-consistent interpretation of cis-erythro selectivity and trans-threo selectivity become possible by considering the solvation effect in addition to the substituent effect.

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Effects of noncyclic cyanamides on the gelatinization of waxy corn starch (WCS) suspension, containing amylopectin as a major component, were examined by analyses of differential scanning calorimetry, X-ray powder diffraction, and Fourier-transform infrared spectroscopy by the attenuated total reflection method. The temperature for the gelatinization of WCS suspension decreased by addition of urea, thiourea, and biuret in comparison to that without additives. These results suggested that the amino, imino, carbamoyl, and thiocarbamoyl groups of additives might have affected the collapses of the intra- and intermolecular hydrogen bonds of the WCS by forming hydrogen bonds with hydroxy groups in the WCS. However, the temperature slightly increased with the increase of the concentration of guanidiniurn salts except for guanidine hydrochloride. The inhibition effect on the gelatinization might have been explained by the anion-constituting guanidinium salts.

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The formation of molecular aggregates of reversed micelles in lacquer tree paint assumed from the molecular structure of urushiol was investigated using electron probe microanalyzer. Results of the microanalysis on lacquer tree paint film containing Fe ions showed that aggregates of reversed micelle structure are formed in KUROME-process and curing.
The photodegradation of lacquer tree paint fil ms cured under various conditions was also studied from the variations of IR spectrum, oxygen content, and exothermic heat with exposure time. Results obtained supported the formation of reversed micelles in the lacquer tree paint films.
In addition, measurements made in the present study were found to provide infor mations useful for estimating the initial stage of photodegration.

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Measurements of color difference, gloss, and surface structures on lacquer paint films were made to obtain an insight into their photodegradation and the results were discussed in terms of the internal structure and the photodegradation mechanism proposed in a preceding paper based on reversed micelle structure in lacquer tree paint. It was found that the degradation can be readily evaluated by correlating visual phenomenon with the variations of chemical structures.
Chemical degradation in particles of reversed micelle structure cou ld be explored from the color change obtained from measurements of color difference. Definite tendencies of decrease in red-series, coloration of yellow-series and increase in whiteness were confirmed from the measurements on the cured lacquer tree paint films as a function of exposure time.
Furthermore, results obtained from mesurements on gloss an d surface structure suggested that particles of reversed micelle structure dissociate from the cured lacquer tree paint films owing to weak interactions between reversed micelles. It was deduced that the variation in these results with exposure time could be ascribed to the difference in the size of dissociating particles.
The results obtained in the present study gave a further indication that the urushiol takes the reversed micelle structure in lacquer tree paint films.

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We succeeded in the crystallization of the title oligomeric ester, which was denoted hereafter as polyarylate, and was sythesized by the melt condensation polymerization of bisphenol A and diphenyl terephthalate/isophthalate (mole ratio 1/0.5/0.5) contacting with the proper solvent. Oligomeric polyarylate could be crystallized in a solvent whose solubility parameter was from 8 to 10. This oligomeric polyarylate had a heat of fusion from 2 to 20 J/g, and the melting temperature was changed from 140 to 220°C depending upon the crystallizing solvent and the reduced viscosity of the oligomer used. When the same oligomer was used for the crystallization, the melting point increased with the increase in the heat of fusion. However, with the increase in the reduced viscosity of the oligomer, the heat of fusion decreased, while the melting point and glass transition of the polymer increased with the increase in the reduced viscosity of the oligomer used, and finally, both reached inthe saturated points with the in crease in the reduced viscosity of the oligomer used. The X-ray analysis for this solvent-induced crystallized oligomeric polymer showed partially crystalline nature. A spherulite structure was observed using a photomicroscope, and a detailed structure of the crystallized structure was also discussed using a scanning electron microscope.

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Adsorption states of mercury on activated carbon in the presence of Br- ion were studied with an analysis of average coodination number and a thermal analysis of activated carbon adsorbed mercury. Activated carbons which were made from coal (A. C. B) and coconut shell (A. C. C) were used. Average coodination number of Br- ion adsorbed on activated carbon was calculated from Br- ion concentration obserbed with Br- ion electrode and mercury concentration in final solution. These activated carbons reduced Hg²⁺ at pH 7 but the reduction of Hg²⁺ was not clarified at pH 1.4. Main adsorption species of Hg ( I I) were [HgBr₂] and [HgBr₃]- at pH 7 and pH 1.4 and the amount of adsorbed [HgBr₃] was in creased with an increase in Br- ion concentration. Furthermore, adsorption of Br- ion and/or [HgBr₄]^2- jwere suggested at higher Br- ion concentration at pH 1.4. Adsorption ability of both activated carbons for [HgBr₂] and [HgBr₃] at pH 7 and for [HgBr₃] at pH 1.4 resembled each other. When the activated carbons were oxidized with Fe³⁺ in acidic solution, Hg²⁺ was not reduced at pH 7 and adsorbability of [HgBr₃]- on A. C. C increased but decreased on A. C. B.
From these results, it is clarified that activated carbon reduces Hg²⁺ at pH 7 even if Br- ion is present and adsorption species varies with Br- ion concentration.

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The effect of microwave irradiation on Michael addition of β-dicarbonyl compounds (acetylacetone, methyl acetoacetate, dimethyl malonate and diethyl ethylmalonate) to methyl vinyl ketone was investigated by using six different metal acetylacetonate catalysts, i. e., Cr (acac)₃, Mn (acac)₂, Fe (acac)₃, Co (acac)₂, Ni (acac)₂ and Cu (acac)₂ without any solvent.
The microwave irradiation markedly accelerated the addition reaction, reducing the reaction time dramatically in comparison with the case of mechanical stirring (1/100 1/1400). The yields of the products were also moderately improved, and the values of the yield were dependent on the metal acetylacetonate catalysts. Thus, the order was well correlated with the electronegativity of the metal cation of the metal acetylacetonate catalysts.

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