Room temperature X-ray diffraction patterns of Pb (Zr_xTi_l-x)O₃ prepared by solid-state reaction showed the coexistence of tetragonal and rhombohedral phases in a composition near the morphotropic phase boundary. Above its Curie temperature (550°C), however, this material was distinctly of monophase in view of X-ray diffraction. These results are explained in terms of the occurrence of compositional fluctuation in this material, since “intrinsic PZT” has tetragonal-rhombohedral phase boundary at x=0.55 where the lattice constant changes drastically whereas such a discontinuity could not be observed in the high-temperature cubic region. The actual compositional fluctuation width, δx, was estimated by using the X-ray diffractometrically determined value of Δα/α together with lattice constant vs. x curve at 550°C. A room temperature X-ray diffraction profile of the tetragonal-rhombohedral coexisting specimen was simulated by a computer calculation on the assumption of the occurrence of compositional fluctuation and was compared with the observed profile.

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The acidic dissociation constants, K, of several weak electrolytes (p-nitrophenol, p-cresol, butylphenol, p (1, 1, 3, 3 -tetramethylbutyl) phenol, Bromophenol Blue, p7isopropylben zoic. acid, m nitroaniline, and Methyl Orange) in aqueous solutions of the different concentrations of Brij, 35 (Brij), 20 mmol/l sodium dodecyl sulfate (SDS), and 20 mmol/l hexadecyltrimethylammoni. um bromide (HTAB) were measured spectroscopically ad discussed in terms of the solvent property and the electric potential of the micellar surface of the surfactants. The pK value in the Brij solution was smaller for the cation acids but larger for the other acids than that in the water. The differences between the pK values in the Brij solution and in the water increased with an increase in the concentration of Brij. Addition of HTAB to the aqueous solution decrease d the pK values, while SDS increased them. These results lead the following conclusions. ( 1 )The decrease in the pK values of the, cation acids and the increase in those of the other acids in the Brij solution were interpreted as showing that the micellar surface' of Brij had the nature of mixed solvent of water and poly (ethylene oxide), ( 2 ) The value of the surface potential of an ionic surfactant micelle could be estimated by means of the measurement of the dissociation constant of solubilized weak electrolytes under the assumption that the pK value on the micellar surface of the ionic surfactant at zero 'charge is equal to that of the nonionic surfactant.

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It was found that the spherical particles of alkaline earth metal silicates were formed by interfacial reaction method, in which the silicates were formed by the reaction of sodium silicate aqueous solution emulsified in benzene with alkaline earth metal chloride aqueous solution.
The microphotographs of the silicate spherical particles prepared by this method are shown in Fig.1.
The s u rface structure of the silicate spherical particles was determined from the adsorption isotherms of water vapor. The isotherms were also measured after alkaline earth metal was leached out with hydrochloric acid.
Some properties of the silicate spherical particles are. shown in Table 1, in which SN₂ and SH₂O were determined by the BET method from nitrogen and water vapor adsorption isotherm s, respectively.
The silicate spherical particles possessed balloon structures. The shell of the balloon was highly porous in the cases of the magnesium silicate and the calcium silicate, but it was n ot porous in the cases of the strontium silicate and the barium silicate.
However, the micropores having the diameter of the orde r of the molecular size of water probably exist on the surface of the “nonporous” strontium and barium silicate particles. The pore radii of the porous slicates determined from the adsorption isotherms of water va por were in the range 5-100 Å.
The mechanism of the formation of the spherical particles were discussed.

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The hydrophobic powder of calcium carbonate (CaCO₃) was prepared by interfacial reaction method, in which one of the reactant was an emulsion consisting of aqueous solution of calcium chloride and benzene, and the other was aqueous solution of sodium carbonate, and the reaction had been made at surface of drops of liquid.
It was f ound by X-ray diffraction that the CaCO₃ powder was composed of two crystalline modifications, calcite and vaterite. And also, it was recognized that the fraction of calcite and vaterite was a little dependent on the emulsifying conditions.
It was found that the vaterite was transformed to calcite in water phase, as a function of time, and the reaction rates were 1.2%/hr at room temperature and 2.5%/hr at boiling water temperature respectively.
It was reco g nized that the kinetic data of the transition were applicable to Avrami's equation, one of the solid state models, and the slope of lines was 1.025.
These results suggest that the transition occurs in the solid phase. But, it could not be disregarded that the dissolution and deposition of CaCO₃ had played a significant part of the transition, because the transition actually took place in the presence of water.

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A photosensor was prepared by coating a dispersed zinc oxide-resin layer on an aluminium plate. This sensor was imagewisely exposed to light and metallic zinc was electrolytically deposited on it in an aqueous 10^-2 mol/l zinc acetate solution. As nuclei a small amount of metallic zinc on a sensor is effective for the physical development process which produces a visible image, and is also served as a reducing agent for 2, 3, 5-triphenyltetrazolium chloride (TTC) and phosphomolybdic acid (PMo) to produce 1, 3, 5-Triphenylformazan Red (TF) dye and Molybdenum Blue (MoBlue), respectively. In these processes, the minimum exposure energy required for obtaining dye image is 10 lux-sec and the maximum density is above 2. The electrolytically deposited zine image obeys the reciprocity law between 100 and 5000 lux sec when the exposure time is 0.3-20 sec.

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Distribution of cations and vacancies in defective spinel, MgO⋅ 3Al₂O₃3, was examined by means of the Fourier analysis and the least squares computation in which a program had been revised so as to solve the distribution of solid solution components and vacancies.
Programs for checking the double reflection and for the absorption and extinction correction were also written and applied.
In the case of a defect ive spinel, MgO⋅ 3Al₂O₃3, it is probable that the structure with space group Fd 3 m is slightly changes, for example, into that with F 43 m. The tetrahedral sites are almost filled up and almost all vacancies exist in the octahedral sites.

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Emerald single crystals were grown by a molten V₂O₅ flux technique, at soaking temperature range from 1010 to 1050°C, using the natural beryl seeds. Temperature difference between the seed and the nutrient was 10-35°C.
The maximum growth w eight was about 6.17 g (approximately 31 carat) under a condition of soaking at 1010°C for about 40 days and the temperature difference of 15°C. The color of the synthetic emerald single crystal was nearly dark green due to the presence of small amounts of Cr and V elements.
The growth patterns of a roundish hexagonal, or dodecagonal, a roundish rectangular and a slender elliptic spirals were observed on c-plane at a growth rate of 2.2 x 10^-3 mm/hr, m-plane at 2.5 X 10^-3 mm/hr and a-plane at 2.5 X 10^-3 mm/hr, respectively.
Three part on the c-plane, namely, the seed, synth etic emerald and the intermediate region between the two were examined by transmission Laue and chemical etching methods. The Laue spots of the three parts were the same and there were no shift of crystal direction among them. Dislocation densities of the natural beryl and the intermediate site were found from results of chemical etching method to be 2.3 and 2.5 x 10⁴/cm², respectively. But a dislocation density of synthetic emerald near the seed was 1.7 x 10⁴/cm² and that of synthetic emerald decreased to the order of EP or 10²/cm² as the sample got nearer to its surface.

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The temperature distribution and thermal convection in a molten V₂O₅ flux were studied by simulation experiments. The temperature distributions within a platinum crucible heated at a bottom about 950 and 1050°C were measured and its approximately symmetrical and steady distribution was revealed by profiles of isotherms. The temperature at the centre was lower than that of the inner wall of the crucible, keeping the horizontal temperature difference within 3-5°C. The pattern of the isotherms were very sensitive to the shape of a crucible and the presence of a baffle plate.
From the calculation of Ra yleigh number of the molten V₂O₅ flux, the thermal convection of it could be classified as natural or free convection.
The flow velocities and directions were o bserved by simulation experiment of thermal convection of aqueous glycerine solution (η=41.3 centipoise) in a stationary crucible because of the colored V₂O₅ melt and high temperature. Without an addition of a nutrient in the bottom of the crucible, the direction of thermal convections at upper side of the baffle plate were opposite to that of lower side of the plate. On the other hand, the convections of the same direction were observed by use of a nutrient, and thermal convection were divided broadly into two groups, that was, a small turn flowing around a seed and a large turn flowing through the hole of baffle plate.
Flow velocities of thermal convection obtained were about 0.0 6-0.08 cm/sec for vertical Δt of about 4-6°C, and 0.10-0.12 cm/sce for vertical Δt of about 15°C. It was found that the flow velocity was increased with an increase of the vertical temperature difference.

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The kinetics of the solvent effect on the oxidation reaction of iron (II) ion with hydrogen peroxide was investigated spectrophotometrically. It was found that 3.0 mol of iron (II) ion and 2.7 mol of iron (II) ion were oxidized by one mole of hydrogen peroxide in waterdimethyl sulfoxide and waterN, N-dimethylformamide solutions respectively under the large excess of iron (II) ion to hydrogen peroxide and air-saturated solutions. The rate equation is d[Fe³⁺]/dt= k_obsd[Fe²⁺][H₂O₂], where k_obsd, is the observed second-order rate constant. The rate-determining step would be the bimolecular reaction between iron (II) ion and hydrogen peroxide. The rate constant k for the rate-determining step is represented by k_obsd=/x where x is the mole ratio of iron (II) ion to hydrogen peroxide reacted. The rate constant k obtained in O.50 mol fraction of dimethyl sulfoxide and in 0.50mol fraction of N, N-dimethylformamide is 2.7 times and 1.7 times larger than that in aqueous solution respectively. The acceleration o f the reaction rate due to the addition of organic solvent may be mainly related to the change in redox potential of iron (II) ion.

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The method is described for the atomic absorption spectrophotometric determination of copper, zinc, lead, cadmium and manganese in water sample, after preconcentration using chelating resin in sodium form. In the present experiment, the synthetic sample solution was passed through a 1.0x25 cm column of chelating resin packing with ca.1.7 ml in sodium form. These metals were adsorbed completely on the resin in the pH range of 6.0-8.0 and eluted effectively with 50 ml of 1 N nitric acid at an elution rate of 5-10 ml/mm. The effluent was analysed by atomic absorption spectrophotometry. The various factors such as pH, acid concentration, flow and elution rates, amount of resin and presence of diverse ions were studied, and following experimental results were obtained ; (1) Chelating resin was used in sodium form. (2) Recovery of five metals was maximum in the pH range of 6.0-8.0. (3) A mounts of chelating resin were ca.1.7 ml in sodium form. (4) Elutriant volume of 1 N nitric acid was 50 ml. (5) Flow rate of eluent and elutriant was 10-20 ml/min and 5-10ml/mm, respectively. (6) Effect of diverse ions such as sodium, potassium, chloride, sulfate, etc. was found to be negligible for the determination of the metals.
The method has an advantage that it can concentrate trace am ounts of metals from much larger volume of water sample than handled by solvent extraction or by evapo rator concentration methods. The recovery of each metal was 95-100% in 50 ml of 1 N nitric acid, and the coefficient of variation was 0.7-2.8%. The method was successfully applied for the determination of metals in brackish and coastal waters.

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A highly sensitive method has been developed for the determination of trace amounts of copper. This method is basad on the catalytic action of copper on the oxidation of o-amino- phenol (AP) by dissolved oxygen. In ammonia alkaline solution, AP was oxidized to phenoxazine derivative (POD) which could be extracted into chloroform and showed a max i mum absorbance at 414 nm in chloroform.
Under the following condition, AP: 1.5 x 10^-4 mol/l, pH: 9.3 (1 mol/l ammonia buffer used), Temp.: 20°C, V_aq / V_org: 3, V_org: 10.0 ml, reaction time: 30 min, linear relationship was obtained between the absorbance (414 nm) of POD extracted into chloroform and the concentra tion of copper (II) up to 20 ng-Cu/ml. By adjustment of variables affecting the absorbance such a s reaction time and temperature (Figs.3 and 6), sensitivity was controlled so as O.1 ng/ml of copper could be determined. In this method, an apparent molar absorptivity was 7.2 x 10⁵ and 3.4 X 10⁶ l/mol·cm under the conditions 20°C, 30 min and 50°C, 30 min, respectively.
Among diverse ions, cobalt (II), manganese (II) and vanadium (IV) cau s e an accelerating effect while iron (III) and chromium (III) cause a deaccelerating effect. The interference by iron (III)can be eliminated by the addition of F^-. The standard deviation at a copper level of 18 ng/ml is 3.5%.
T h e present method was succesfully applied to the determination of trace copper in river water and tap water.

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Extraction-polarography in an organic phase is very useful for the investigation of the extraction mechanisms. Polarographic behaviors of tetraethylammonium 1-pyrrolidinecarbodithioate (Et₄Npcd) and iron (III)-1-pyrrolidinecarbodithioate (iron (III)-pcd) chelate were investigated in methyl isobutyl ketone (MIBK) containing 0.1 mol/l tetrabutylammonium perchlorate as a supporting electrolyte. Et4Npcd shows an oxidation wave at a dropping mercury electrode (DME) with the half-wave potential of 0.63 V vs. SCE. The oxidation process is diffusion- controlled with one electron transfer. A d. c. polarogram for iron (III) -pcd chelate in anhydrous MIBK shows one oxidation wave and one reduction wave at the DME. The half-wave potentials are- 0.07 and -0.62 V, respectively. The oxidation wave is due to the mercury dissolution by the iron (III) -pcd chelate and the reduction wave is due to the one electron reduction of iron (III) to iron (II) -pcd chelate. The cyclic voltammogram for the iron (III)-pcd chelate at the platinum disk electrode shows an oxidation wave to iron (IV) chelate and a reduction wave to iron(II) chelate. The peak potentials are about +O.5 V and -0.5 V, respectively. Iron (III) is quantitatively extracted from a citrate buffer with Et₄Npcd into MIBK in the pH range above 4.0. From the polarography in the extract, it was found that pcd and citric acid are co-extracted with the iron (III)-pcd chelate and that the iron (III) chelate and pcd are slowly decomposed.

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Irradiation (Hg lamp, high pressure) of trans-azobenzenes dissolved in acid chlorides results in the formation of N, N'-diacyl-chlorohydrazobenzenes. Upon interuption of irradition, intermediary N'-acyl-chlorohydrazobenzenes are formed, which were isolated by preparative thin layer chromatography. Photoreactions of monosubstituted azobenzenes with acetyl chloride give mixtures of three positional isomers with respect to chlorine. Structures and ratios of the above products were determined by gas chromatographic method previously mentioned. The remote nitrogen, attached to unsubstituted phenyl group of azobenzenes monosubstitued by an electron donating group, is mainly acetylated and subsequently chloride ion attacks substituted benzene nucleus. The fact was interpreted in terms of the resonance stabilization of the resulting nitrenium ions.

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Treatment of aromatic aldehyde or crotonaldehyde N-alkoxycarbonylhydrazones [1 a-e] with lead tetraacetate afforded 5-substituted 2-alkoxy-1, 3, 4-oxadiazoles [2 a-e]. However, similar treatment of butylaldehyde N-ethoxycarbonylhydrazone [1 f] with lead tetraacetate gave 5-propy1-2-ethoxy-1, 3, 4-oxadiazole [2 f] along with ethyl 1-acetoxybutylazoformate[3 f].
Upon treatment of [2a- c, 2e, 2f] with tertiary amines, the alkyl moiety of alkoxyl grou ps at the 2-position migrated to the nitrogen at the 3-position to give 5-substituted 3-alkyl-2, 3dihydro-1, 3, 4-oxadiazol-2-ones [4 a-c, 4 e, 4 f]. The rate of this migration depended on the amines employed, decreasing in the order: 1, 5-diazabicyclo[5.4.0]undec-5-ene (DBU) >triethylamine> pyridine. The ease of migration of the alkyl group decreased in the order: methyl>ethyl> isopropyl.

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When carboxyl group of humic acid is replaced by thiocarboxyl group, thiohumic acid (THA)is formed. THA was prepared from the regenerated humic acid obtained by the oxidation of Miike bituminous coal with nitric acid as shown below:
THA has an excellent adsorptive ability for methylmercury (II) chloride (Fig.1) and this adsorptive ability is scarcely influenced by pH or NaCl present in an aqueous solution of methylmercury (11) chloride. THA which adsorbs methylmercury (II) chloride can be regenerated by the treatment with 4 N HCl (Fig.3). THA has an excellent adsorptive ability also for mercury (II) chloride. By adding 100 mg of THA to 100 ml of an aqueous solution of Hg (II) whose concentration is 1 ppm, the concentration of Hg(II) can be reduced below 1 ppb (Fig.4). The adsorptive ability of THA for mercury (II) chloride is not affected by the addition of HClO₄ (Fig.5) and scarcely affected by the addition of HC1 or NaCI when the concentration of HC1 or NaCl is less than 0.1 mol/1 (Fig.6, 7). About 10000 ppm of Ca²⁺ or Fe³⁺ coexisted in an aqueous solution of Hg(II) does not affect the adsorption of Hg (II) on THA (Fig.8). In comparison of the adsorptive ability of THA with that of humic acid, it was concluded that the coordinate bond between COS^- group and mercury contributes markedly to the adsorption of mercury on THA. THA containing CO^- group, a soft base, was found to have a selective adsorptive ability for mercury.

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The basic idea of the previously reported spectrophotometric determination of the solubility of dye, defined as concentration of monomer in equilibrium with a large amount of fine- crystalline dye dispersed in water, has been extended to estimate solubility, S₁, of dye in the presence of dispersing agent of concentration bellow its CMC and concentration, S_c, of complex formed between them by means of the following simultaneous equations,
Here K is an equilibrium constant of complex formation, C_s is concentration of dispersing agent at equilibrium, and A₀ is extrapolated absorbance of linear plot of over -all absorbance against-dy-econcentration at its higher concentration region. ε₁, ε_c and ε_s are molar extinction coefficients of dye monomer, complex and dispersing agent, respectively. ε is mean molar extinction coefficient (apparent) of fine-crystalline dye. The disperse dyes used in these experiments are C. I. Disperse Orange 3 (DO 3) and 1, 4-diaminoanthraquinone (DAA), and the dispersing agent is sodium 2-naphthalenesulfonate-formaldehyde condensate (NaNSF). Experimental results revealed that with increasing concentration of NaNSF S_c increases but S₁ levels off to a almost constant value after initial slight drop. Both S₁ and S_c increase with increasing temperature. In particular, the fact that S₁ increases exponentially with increasing temperature suggests that dissolution of disperse dye is dominated also by its fusion process in the present case. The total concentration of the molecular aggregates of dye and complex decreases gradually to zero in case of DO 3 but increases in case of DAA with increasing concentration of NaNSF.

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1, 2, 3, 4-Tetrafluoroanthraquinone [3a] and its 6-substituted compounds [3b-3d] were prepared by the Friedel-Crafts condensation of terafluorophthalic anhydride [1] with benzene, toluene, fluorobenzene and chlorobenzene, followed by the ring-closure with sulfuric or fuming sulfuric acid. Unsubstituted tetrafluoroanthraquinone [3 a] was also prepared by heating 1, 2, 3, 4-tetrachloroanthraquinone with potassium fluoride in sulfolane.1-Amino-5, 6, 7, 8-tetrafluoroanthraquinone [5 a] and its 2-methyl-, 2-fluoro and 2-chlorosubstituted derivatives (5b-5d) were obtained by nitration of [3 a]-[3 d] with HNO₃-H₂SO₄, and subsequent reduction of nitro group with SnCl₂-HCl. The first bands in visible spectra of 1-amino-5, 6, 7, 8-tetrafluoroanthraquinone and its 2-substituted derivatives shifted about 10 nm bathochromically from that of 1-aminoanthraquinone.

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Catalytic degradation of polystyrene on silica-alumina under a nitrogen atmosphere was carried out by a batch process. The composition of the distillate and the intrinsic viscosity of the residual polymer were examined at 250-300°C, at which thermal depolymerization was scarcely observed. The recovery of aromatic compounds from polystyrene by catalytic degradation was investigated and the results were compared with those of non-catalytic degradation.
In the absence of the catalyst, the distillate was obtained at above 310°C and it mainly consisted of styrene (70 wt%), α-methylstyrene (2 wt%) and toluene (1 wt%) while in the presence of the catalyst, the distillate mainly consisted of benzene (53-35 wt%), cumene (15wt %), ethylbenzene (10 wt %) and many unidentified products having high boiling points. With increasing reaction temperature or relative amount catalyst to polystyrene, the yield of the distillate increased. With increasing flow rate of carrier gaseous N₂, the yield of benzene decreased and that of the high boiling products increased while that of the other products remained constant. Catalytic degradation of polystyrene sample whose molecular weight was reduced by non-catalytic degradation, gave the same yield and the composition as the original polystyrene sample. When the utilized catalyst was extracted by tetrahydrofuran and was reactivated, the activity returned to two thirds of the original one.

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The mechanism of adsorption of the Hg (II) ion on activated carbons (prepared from coal by steam activation method) has been studied. The following conclusions were obtained from the effects of pH, anions, foreign metallic ions and temperature on adsorption of the Hg (II) ion and the desorption of mercury from activated carbon.
(1) The Hg(II) ion is adsorbed very efficiently on activated carbon in a HCl acidic medium (pH 1-4).
(2) Adsorbability of Hg (II) on activated carbon is improved by the addition of halide ions. The order of this improving effects of halide ions is F^- < Cl^- < Br^- < I^-. This order is the same as that of the stability constants of HgX₄^2- complexes and indicates that Hg(II) is adsorbed very well on activated carbon in the form of the HgX₄^2- complex.
(3) Mechanisms of adsorption of Hg( II ) in an acid ic (HC1) and an alkaline (NaOH)medium differ from one another. In an acidic medium, the HgCl₄^2- complex is reversibly adsorbed on activated carbon. On the other hand, the adsorption of Hg(II) in an alkaline medium is irreversible. In an alkaline medium Hg (II) is considered to be adsorbed on activated carbon in the forms of Hg(OH)₂ and Hg metal which is generated by the reduction of Hg(II) the surface of activated carbon. If I^- is present in the Hg( II) solution, Hg(II) is adsorbed very well in the form of HgI₄^2- even in an alkaline medium.
(4) Mercury adsorbed on activated carbon in a HCl acidi c medium is easily eluted with a dilute aqueous solution of sodium hydroxide.
(5) The adsorption of Hg (II) on activate d carbon in a HC1 acidic medium is little affected by the addition of Na⁺, Ca²⁺ and Fe³⁺ even if the amount of these metallic ions are 100 times that of Hg (II).

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The polymerization of isoprene by Ti(OBu)₄ -AlEt₂Cl and Ti(OBu)₄ -AlEt₃ catalysts to which AIX, was added has been investigated.
In Ti(OBu)₄ -AlEt₂Cl-AlX₃ catalysts, the maximum activity of polymerization is exhibited when AlEt₂Cl/AlX₃= 3 and total Al/Ti = 8 (represented as CAT I -X); and in Ti (OBu)₄ -AlEt₃ -Al X₃ catalysts, when AlEt₃/AlX₃=1 and total Al/Ti = 7-8 (represented as CAT-II-X). By CAT-I -Br and CAT- II -Br, cis-1, 4-polymer with high molecular weight, [η ] >4, is easily obtained.
The rate equations in the case of both catalysts are of first order with respect to concentration of isoprene and the activation energies are from 8.7 to 12.0 kcal/mol.
The number average molecular weight, M_n, of the polymers obtained by CAT I -Br and CAT-II -Br is larger and M_w /M_n value is smaller than those of the polymers obtained by CAT I -Cl and CAT II -Cl. Then, it was assumed that the less degree of chain transfer occurred in the polymerization by the catalysts which contained AlBr₃.

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In the Ti(OBu)₄-AlEt₂Cl-AlBr₃ catalysts for cis-1, 4-polymerization of isoprene, the effect of synthetic procedures of catalysts on the polymerization activity in benzene and on the polymer properties were studied and the activating processes of these catalysts were discussed.
When AlEt₂Cl, AlBr₃ and Ti(OBu)₄ were added in this order and AlEt₂Cl was premixed with AlBr₃ before the addition of Ti(OBu)₄ cis-1, 4-polymerization of isoprene proceeds feasibly. Lower the concentrations of the catalysts, the finer is the particle size of solids in the catalysts, the wider is the surface area of these solids and consequently the higher is the activity toward polymerization. Besides, it was confirmed that neither the solid portion nor the liquid portion alone showes the activity toward polymerization.
Also, it was confirmed that the valence of Ti in the solid portion is +3 and the effective component in liquid portion is AlEt₂Cl.

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In order to obtain the data concerning nitrile band (vc≡N) appeared in IR spectra of heat- treated polyacrylonitrile, variations of vc≡N under different heating conditions were studied in detail about one kind of solution-polymerized sample.
Three bands were observed, except the or iginal strong band (2240 cm^-1). These wave numbers were 2225, 2210-2200 and 2190 cm^-1. Appearing condition of each band was selected out and summarized qualitatively. Unreported assignment of 2225 cm^-1 band was discussed and the following relationship was obtained between the intensity of 2225 cm^-1 band and that of 2240 cm^-1 band.
Where ε is the molar extinction coefficient of corresponding band.

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In was found that poly (ethylene glycol) (PEG) exerts a considerable effect on the reversible contraction and dilation of poly (methacrylic acid) (PMAA) membrane caused by the change in ionization of carboxyl group. The effect is closely related to the chain length of PEG. PEG of molecular weight 2000 brings about an instantaneous and significant contraction of PMAA membrane. PEG, whose molecular weight is lower than 2000, also brings about a contraction rapidly but the change in length is not remarkable, whereas PEG, whose molecular weight is as high as 7500 or 20000, brings about an extensive contraction slowly. These results were discussed in terms of the complex formation of PEG with PMAA membrane. When alkali was added to the embedding solution of the membrane, the change in length of the membrane Δl_NaOH (cm) after t minutes, is expressed by the following equation: Δl_NaOH=10^b · t^a where a and b are constants.

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An isotactic polypropylene was thermally degradated under atmospheric pressure at 380°C. Th e obtained products were hydrocarbons being liquid at room temperatures. The analy tical gas-liquid chromatogram (GLC) of these products including trace component s (Fig.3)showed more than forty peaks. Among the components, the eight major ones, which were excess of 3 wt % of the total weight of the products (Table 2) and corresponded to the GLC peak numbers 1 to 8 in Figure 3, were dealt with. The above eight components were obtained by the careful use of a precision fractionator. The chemical structure of each component was determined principally by ¹³C NMR spectra and Mass spectra. Ultimately, the eight components were identified in terms of the retention time of GLC as follows: pentane, 2-methyl-1-pentene (the dimer olefin of propylene), 4-methylheptane (the trimer paraffin), 2, 4-dimethyl-1-heptene (the trimer paraffin), 4, 6-dimethylnonane (the tetramer paraffin), 2, 4, 6-trimethyl-1-nonene (the tetramer olefin), 4, 6, 8-trimethylundecane (the pentamer paraffin), and 2, 4, 6, 8-tetramethy1-1undecene (the pentamer olefin).
In ¹³C NMR spectra of the tetramer paraffin (Fig.4), the tetramer olefin (Fig.5), the pentamer paraffin (Fig.6) and the pentamer olefin (Fig.7), the resonances due to the tacticity of dyad and triad of the propylene oligomers were observed. On the basis of the results of determination of chemical structures of the thermal degradation products and of assignment of resonances due to the tacticity of the oligomers, it was found that the thermal degradation products consisted of about 72 wt % of branched mono-olefins and about 21 wt % of branched paraffins, and that polypropylene having isotactic structure was thermally degradated into propylene oligomers having heterotactic structure. Finally, the thermal degradation mechanism of polypropylene was discussed.

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Recently, by means of microthermal analysis, 4-hydroxyisophthalic acid was found to be formed as an intermediate in both carboxylation of alkali phenolates and rearrangement of alkali salicylates into alkali p-hydroxybenzoates. The thermodynamic studies based on th e argument for the chemical equilibrium suggested in the previous paper were made by using the thermochemical data estimated from the additive nature of the component data.
It was found that many experimental facts were interpreted well in terms of the results obtained by these studies.

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The S_2pNo binding energies of the titled compounds were measured by means of ESCA. The participation of the 3 d-orbital on the sulfur atom in 2 H-1-benzothiopyran-2-ones was discussed. The sulfur binding energies of thiopyrylium compounds were found to be 0.5 and 1.0 eV larger than that of the sulfide [1]. These results gave direct evidence for a criterio n of the aromatic character of sulfur-containing nonbenzenoid aromatics.

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