The self-diffusion coefficient of each component in the binary systems was measured by the Fourier transform of the spin echo using the spin echo pulsed gradient method over the whole concentration range at 25 and 32°C. The self-diffusion coefficient of CH₃CD₂COOD in D₂O was measured by the steady gradient method at 25°C.
The values of the self-diffusion coefficient of CH₃CD₂COOD in D₂O corrected for the visco sity of water (η_D2o/η_H2o=1.23) was in good agreement with that of CH₃CD₂COOD in D₂O. The self-diffusion coefficients of water in both systems were larger than those of solute over the whole concentration range. This means that the long-lived hydrated complexes do not exist in both systems. The self-diffusion coefficients of propionic acid and t-butyl alcohol in water show minimum at x_s=0.35 and 0.3, respectively. The self-diffusion coefficients of the solutes in both systems closely correlate with the fluidities of the corresponding solutions.
The self-diffusion coefficient of water in t-butyl alcohol solution is constant a bove; x_s=0.5, while in propionic acid it shows a minimum at x_s=0.6. In both systems, the structural rein forcement appears in water-rich region, and the water molecule behaves as a normal polar molecule in water-poor region.

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In order to clarify the factors affecting enantioselectivity in nonaqueous surfactant solutions, pseudo-first order rate constants ( k_obs)h ave been measured for the aminolysis of p-nitrophenyl esters of L and D-mandelic acids, N-benzyloxycarbonyl L and D-amino acids and acetic acid by reversed micelle-forming surfactants, (+) and (-)-C6HH(CH₃)NH₃^+-OOC(CH₂)10CH₃, CH₃ (CH₂)11NH₂⁺ _L-^-OOCCH (CH₂C6H₅)-NHCO(CH₂)10 CH₃ and C6H₅CH₂NH₃^+-OOC(CH₂)10 CH₃ in hexane and benzene (Fig.2, 4 and 5). By analyzing the k_obs vs. [Surfactant] profile obtained (Fig.3 ), the rate constants and the enantiomer rate ratio (LID) were obtained as a measure of enantioselectivity for surfactant monomers and aggregates (Table 2-4). Higher rate constants and enantioselectivity were observed for the aggregates as compared to the monomers in any reaction system. In the aggregate systems the selectivity was found to be caused by the difference in the free energy of enantiomer-aggregates complex formation, indi eating different binding constants for the complex (Table 2 and 3). This was supported from the facts that neither selectivity nor different binding constant was observed in optically inactive surfactant solutions (Table 2). The effective enantioselectivity was observed for the surfactant having asymmetric center near the cationic part of the catalytic function group, - NH₃^+-OOC-, of the surfactant (Table 2-, 4).

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During the desorption process from the interconnecting pore texture by the bottle-neck mechanism, the vapor/liquid interface is not formed for all pores in the texture. The pore which is not faced toward the vapore phase is described as being blocked. Evaporation from the pore is prohibited regardless of pore size or relative pressure, and then hysteresis behavior appears.
For quantitative evaluation of the blocking effect, the percolation process on a network model shown in Fig.1 has been simulated with the aid of a digital computer (Fig.2). For obtaining information on the porous substances with extensively different sizes of granules, the Monte-Carlo simulation method was applied to three types of the model with different ex ternal forms (Fig.3, 4). The surface obtained as solution of the percolation problem was smoothed by using spline functions (Fig.5), and thus, the ψ-π-σ relation could be reffered by interpolation of the spline parameters stored in a computer.
It become possible to get plausible explanation for such phenomena as scanning adsorption isotherms (Fig.6), light scattering in porous silica impregnated with liquid, and Hg-intrusion into pore texture. Moreover, it was shown that the established configurations of hysteresis loops could be expressed with only little modification of pore size distribution (i. e., shape of adsorption branch) and/or of σ (i. e., size of granules); cf. Fig.7-9.
As characteristics of the pore size distribution and the amount sorbed were normalized by using π and ψ (Eq. ( 3 ), ( 4 )), the blocking effect and therefore the hysteresis were found to be analyzed generally for any porous substance by a brief numerical calculation.

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A thermal desorption study was performed to examine the influence of Na⁺ and Mg²⁺-doping on the adsorbent properties of SnO₂ for water. Three discrete desorption peaks at 435, 490, and 620°C of hydroxyl groups on the pure SnO₂ surface changed into a single peak on Na doping. With an increasing dose of Na⁺, the temperature of this peak lowered and the peak area decreased. The peak almost completely disappeared at 2.0 atom% Na⁺. At its expense, a broad and large peak appeared at ca.200°C, which was attributed to the desorption of molecular species adsorbed at the surface oxygens through hydrogen bonding. Similar results were obtained in the case of Mg²⁺-doping. However, the lowering of the desorption tem perature of surface hydroxyls was less remarkable. This is probably due to the difference in electronegativity between Na⁺ and Mg²⁺.
The desorption spectra of surface hydroxyls from the doped SnO⁺ samples varied with the pretreatment atmosphere at 800°C. The pretreatment under helium or in vacuo resulted in a decrease of the peak area, lowering of the desorption temperature, or appearance of a small low-temperature peak. The surface area of the doped samples also decreased by the pretr eat ment under helium or in vacuo. This kind of variation of the desorption spectra was suggested to arise from some surface reconstruction associated with the sintering process of the SnO₂ particles.

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Changes inithe contents of trace impurity elements in tungsten filaments (doped K, Al and Si) during lighting time (0, 3, 25 h) of a bromine lamp was determined by the spark source mass spectrometry. The vaporized elements at 2750°C were Fe (32.3 mole ppm/W) Al (24.5), Ba (14.5), Ca (13.3), Na (8.8) and Sr (5.7) after the lighting for 25 h. Potassium was hardly evaporated despite of the high initial content. It was probably due to the formation of potassium aluminosilicate. The composition of a deposit containing Fe, W, Al, Br and 0from the gas phase below 400°C (lamp wall temperature: 500-600°C) was in agreement with the decrease in the content of the impurity elements in the tungsten filament. A thermo chemical calculation supported that bromine and tungsten oxides were formed at a high tem perature near the filament, while tungsten bromides and tungsten bromide oxides were formed near the bulb wall. Their partial pressures were independent of the existence the trace Fe, Al and K. The partial pressures of FeBr₂ and KBr were nearly constant from 800 K to 3000K, and that of AlBrs was constant below 2300 K but lowered steeply above the temperature.

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Physical and catalytic properties of various cation-exchanged 12-molybdophosphates were examined with reference to two acid-catalysed reactions: dehydration of 2-propanol and iso merization of cis-2-butene. It was convenient to classify the catalyst into two groups according to their solubility into water. As summarized in Table 1, group A catalysts were soluble in water, had low surface area and showed multiple dehydration peaks when subjected to DTA TG analysis. Group B catalysts were insoluble in water, had high surface area (higher than 100 m²/g) and had a single peak due to dehydration of physically sorbed water. The catalytic activity for the dehydration of 2-propanol was well correlated to electronegativity of metal cations (Fig.3), indicating the role of the cation in the acidic catalysis.
As Fig.5 and 6 show, activities for the butene isomerization were accelerated by addition of water to the group A catalysts. On the other hand, water retard the activity of the group B catalysts. Enhancement by the added water is due to; (1) hydration of cation to stabilize the cation-anion structure and (2) formation of BrOnsted acid sites through hydrolysis described by eq. (1). These explanations are supported by the fact that the charge of the cation decreased (Lewis acidic strength decreased) upon dehydration and regenerated by rehydration.

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The surface oxides of platinum and gold electrode formed anodically are gradually reduced when held at open circuit in aqueous sulfuric acid. The nature of this reaction was studied by the aid of mainly chronopotentiometric technique. It was confirmed that, for both platinum and gold, the reaction proceeds through the galvanic cell mechanism in which the bare surface of metals act as the anode electrode which oxidizes certain contaminants and the oxide covered surface act as the cathode. From the measurements of short circuited galvanic cell composed of oxidized platinum (or gold) in purified 1 N H₂SO₄ and reduced platinum (gold) in “contaminant” containing 1 N H₂SO₄, it was concluded that formaldehyde used as the contaminant was effective to platinum oxide but not to gold oxide. Both chloride and bromide as the contaminant behave oppositely, being effective to gold but not to platinum. This sort of apparently peculiar behavior of several “contaminants” has been explained by the fact that compounds which are effective as a depolarizer were those oxidized anodically on the oxide free surface of metals.

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A mechanistic study on unusual electrolytic reduction of sodium S (2, 5-dihydroxyphenyl)thiosulfate (H₂QT) has been carried out. The effect of substituents on the reduction potential of various H₂QT derivatives was scrutinized. Polarography and product analysis of the controlled-potential electrolysis showed that the reaction followed the equation: H₂QT +2e → H₂QSH + SO₃^2-, where H₂QSH represented a mercaptohydroquinone. The reduction potential of various H₂QT derivatives shifted towards a more negative value when the sub stituent was electron-attracting and to a more positive one when it was electron-donating.

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The extraction of zirconium sulfate in aqueous sulfuric acid solutionswith trioctylmethylammonium chloride (Aliquat-336; R₃R'NC1) in organic solvents has been investigated under different conditions. In addition, the organic phases extracted sulfuric acid and zirconium sulfate were examined by IR and NMR spectroscopies. It has been found that Aliquat-336 extracts zirconium(IV) from sulfuric acid solutions according to the following ion-exchange reactions.
i) The extraction of sulfuric acid is at first carried out through the equilibria, SO₄^2-(aq) + 2 R₃R'NCl(org) ↔ (R₃R'N)₂SO₄(org) + 2Cl^-(aq) (R₃R'N)₂SO₄(org) + H⁺(aq) + HSO₄-(aq) ↔ 2R₃R'NHSO₄(org)
ii) The extraction of zirconium is expressed as the equilibri um reaction Zr(SO₄)₃^2-(aq) + 2xR₃R'NHSO₄(org) + (1-x) (R₃R'N)₂SO₄(org) ↔ (R₄R'N)₂[Zr(SO₄)₃](org) + xH₂SO₄(aq ) + SO₄^2-(aq) x=[R₂R'NHSO₄]/{2[(R₃R'N)₂SO₄] + [R₄R'NHSO₄]}
Moreover, the hydrolyzed species (R₃R'N) [ZrO (OH) (SO₄)] is formed when zirconium is further extracted in an organic phase.

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For aluminium dihydrogentriphosphates, AlH₂P₃O₁₀⋅H₂O (I) and II type of AlH₂P₃O₁₀(II) various fundamental properties, such as solubilities, densities, surface areas, and heats of reaction (e H) and activation energies (E) of their thermal change into aluminium metaphos phate Al(PO₃)₃, were measured. Further, the adsorption of ammonia gas and amines on aluminium triphosphates, as well as structures of cation-exchanged compounds AlM₂P₃O₁₀. n H₂0 (M=Na, K, NH4), were investigated.
1) At room temperature, solu bilities of I and II in water are found to be 0.01 and 0.05g/₁₀0 cm³ H₂O, respectively. The order of their solubilities in various solvents is NH₃>KOH >NaOH>HCl>H₂O. 2) Densities of I and II are 2.31 and 2.60 g/cm³, and su rface areas are 5.2and <1 m₂/g, respectively. 3) For both I and II, the heat of the thermal change into Al (PO₃)₃ was found to be 11.4 kcal/mol, while the activation energies are 25.3 and 61.9kcal/mol for I and II, respectively. 4) The temperature of the thermal change from I into Al(PO₃) was proved to be closely correlated with the quantity of free phosphoric acid adhered to I. 5) Both I and II adsorb basic materials, such as ammonia gas and amines, quite well. 6) The sample of I, which has a stratified structure, is submitted to ion exchange with univalent metallic ions to form AlM₂P₃O₁₀⋅n H₂O (n= 2 for Na salt, for K salt, 2-1 for NH₄ salt). Their crystal structures were destroyed with the decrease of n.

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The effect of ammonia on the formation of guanidinium ion (GH⁺) by the reaction of urea with triammonium nitridotris (sulfate) (TNS) in the molten state under an atmospheric pres sure, has been studied.
The bubbling of ammonia into the melt during the reaction of urea with TNS (molar ratio 1: 2/3) suppressed side reactions, gave fluidity to the melt, and led to a considerable increase of GH⁺ yield. These results, including the IR spectra of reaction mixtures, the yields of GH+ and by-products vs. reaction temperature, were analogous to those from the reaction of urea with diammonium imidobis (sulfate) (DIS) (molar ratio 1: 1) with the bubbling of am monia. Furthermore, TNS was readily ammonolyzed to ammonium amidosulfate (AAS) and DIS in the presence of urea at the temperature as low as 160°C. Based on these results, the formation path of GH⁺ in the reaction of urea with TNS with the bubbling of ammonia was considered to be substantially the same as that in the reaction of urea with AAS or DIS with the bubbling of ammonia. In these reactions, TNS, DIS and AAS may be taken as equivalent to one another at the molar ratio of 2: 3: 6,

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A kinetic study is carried out on the H₂O₂ oxidation of oxalate, ethylenediamine and ammine complexes of Cr (III) in ammonia buffer solutions between pH 9 and 11. In the prese nce of a large excess of H₂O₂, the oxidation reaction obeys the pseudo-first-order rate law with res pect to the concentration of the complex.
The oxidation rate of the oxala t e complexes is of the first-order with respect to the concen trations of the complex and H₂O₂. The rates of complex consumption agree with th ose of CrO₄^2- formation, showing the stoichiometry of the reaction. The step of coordination o f H₂O₂ to the central atom is suggested to be the rate-determining step.
The oxidation rates of the complexes of ethylenediamine and am m onia are little affected by the concentration of H₂O₂, except for the oxidation of Cr(en)₃³⁺ at pH below 10. The rate s of oxidation of the ethylenediamine complexes agree with the rate of ethylenediamine rele ase. The rate-determining step for the ammine complexes is also presumed to be the release of the ligand molecule (s) from the complex. The results are discussed in connection with the wo rk of Knoblowitz et al.

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Qualitative and quantitative analyses of the amino acids, formed when the hydrocarbon (methane, ethane, ethylene, acetylene) -ammonia-water vapor systems were submi tted to the irradiation with UV light at 185 nm, were investigated. In addition, hydrocarbon-water vapor, hydrocarbon-ammonia, acetaldehyde-ammonia-water vapor, and ethanol-ammonia-water vapor systems were studied. In the hydrocarbon-water vapor systems, many kinds of alcohols and aldehydes were synthesized.
Aldehydes, pre cusors of amino acids and sugars, were found much more in the acetylene-water vapor system than in other systems. The hydrocarbon-ammonia systems, gave quite similar products in kinds of nitriles and amines, even if any of the above hydrocarbons was chosen as a starting material. In the hydrocarbon-ammonia-water vapor systems, twelve amino acids were identified, including two protein amino acids with a hydroxyl group, serine and threonine. In the C₂ hydrocarbon-ammonia-water vapor systems, total yields of amino acids increased in the order of acetylene, ethylene, and ethane. The yield of amino acids increased with an increase of the initial concentration of ammonia and became maximum when the initial concentration of ammonia was equal to that of acetylene.

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Voltammetric behavior of nickel electrode in an alkaline solution has been investigated. When a nickel electrode is preserved in an alkaline solution, a film of Ni (OH)₂ is formed to grow on the electrode. The growing process of the film was found to follow a cube rule when the electrode was kept undisturbed in an alkaline solution, and to follow a paraboloid rule when continuous potential scanning was repeated in an alkaline solution. The nickel electrode covered with the Ni (OH) film was dependent on a pH of the electrolyte. At a pH higher than 11, the following empirical formula was given between the peak height i_p (μA mm^-2) and pH: i_p=k(pH-10.5), where the constant k was 9.6. The electrode potential of the Ni (OH)₂ electrode was O.196V vs. SSE in 0.1 mol dm^-3 NaOH solution. By using the Ni (OH)₂ electrode a s an indicator electrode, the electrolytic oxidation of etha nol in an alkaline solution was examined. The oxidation of ethanol took place at more positive potential than +O.5 V vs. SSE.

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, Gas-liquid chromatographic retention behavior of Be (II), Cu (II), Al (III) and Cr (III) chelates of β-diketones (R₁-CO-CH (R₂) -CO-R₃) was investigated on Apiezon L and Silicone oil F- 50 columns. In each series of metal chelates of the homologous ligands, linear relationship was found to hold between the logarithm of the retention volume (V_R^o-V_G) and the carbon number of the central alkyl group (R₂) or that of the terminal one (R₃) in the ligands. The slopes of the lines are substantially equal, irrespective of the coordination structure of the central metal ion. It seems that the slopes correspond to the increased free energy change due to the increased number of carbon atoms. The intercept of the line varies from a metal to another as far as examined, giving a parameter characteristic to the kind of the central metal ion.

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Extraction of lanthanoids (Ln) with bis (2-ethylhexyl) hydrogenphosphate (D2EHPA, (C₈H₁₇O)₂POOH) has been investigated in the region of high metal loading. Extracted species are polymerized and form gelatinous materials at high metal loading (R_tr>0.15) as shown in Fig.1. Table 1 indicates that the composition of the polymerized species is LnX₃ (X: (C₈H₁₇O)₂POO). Fig.3-(a) indicates that the extractant dependence of the distribution ratio of a lanthanoid is 2.5 power in benzene, and therefore the extraction reaction is represented as Eq. (2) (Ln _(a)⁸⁺+ 5/2 (HX)_2(o) ↔ LnX₃⋅2 HX_(o) + 3 H_(a)⁺). Fig.4 (a) shows that the concentration of a lanthanoid in the organic phase is of first order in the D2EHPA concen tration in the presence of gelatinous materials when benzene is a diluent, and therefore the equilibrium between the organic phase and the gelatinous materials is represented as Eq. (3)(1/p (LnX₃)_p(g) + (HX)_2(o) ↔ LnXLnX₃⋅2 HX_(o)), where p is the degree of polymerization. The dependence on D2EHPA concentration is lower in heptane than in benzene as shown in Fig.3-(b), 4-(b) and 5-(b). The difference can be explained by the fact that the association number of D2EHPA in heptane is more than 2.

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In order to obtain an information on the dyeing mechanism of polyester fibers with disperse azo dyes, interactions between the polyester and azo dye models have been investigated in further details with ¹³C and ¹H-NMR ispectroscopies. Methyl benzoate (MB) was used as polyester model. The dye models were nitrobenzene (NB), benzonitrile (BN), N, N-diethyl aniline (DEA), N-ethyl-N-(2-cyanoethyl)aniline (ECEA), N-ethyl-N (2-hydroxyethyl) aniline (EOEA) and N, N-bis (2-hydroxyethyl) aniline (BOEA).
From the results of the measurement of ¹³C-NMR spectra of the solutions in various molar fractions of the dye models and MB at room temperature, the interactions between the model compounds were considered in relation to their dipole structures. The signals due to the car bonyl, methyl and para carbons of MB shifted downfield, especially larger shifts were observed in MB-EOEA system. On the other hand, the signals ascribed to the para carbons of NB and BN shifted downfield, while upfield shifts were observed for the para carbons of DEA, ECEA and EOEA, in addition to downfield shifts for the a and nitrile carbon of ECEA. These results are ascribed to the dipole-dipole interaction and the hydrogen bonding, a special form of dipole interactions, between the dyes and MB.
The temperature dependences of hydroxyl protons of EOEA and BOEA in various molar fractions of MB were also investigated with ¹H-NMR spectroscopy. The chemical shifts of the hydroxyl protons were remarkably dependent on temperature. This fact may be attributed mainly to the hydrogen bonding between the hydroxyl group of the dyes and carbonyl group of MB.

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The photo-dechlorinations of three tetrachlorobenzenes in 2-propanol were quenched by cis 1, 3-pentadiene [7] (Table 2, 3) and oxygen [9], and sensitized by acetone [8]. The curved Stern-Volmer plots for whole products (Fig.1-4) suggest that the dechlorinations take place from both excited singlet and triplet states.
The results obtained on the reactions wer e as follows (Table 4, 5): (i) All dechlorinations took place more preferably from their triplet states than from the singlet states. (ii) The positional selectivities of dechlorinations from excited states were considerably different between singlet and triplet states.

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Nitrogen type analyses of asphaltenes of Khafji atmospheric residuum and its hydrotreated products were carried out by the USBM-API 60 methods. Although highly polar materials remained on ion-exchange resins after the usual elution procedure, most of them were reco vered by using chloroform as an elution solvent. The yield of each fractionated asphltene did not accurately show the distribution of nitrogen compounds because of the following reasons: ( 1 ) association of asphaltene molecules prohibited the functional groups from interaction with the resins, ( 2 ) multifunctional compounds were included in a considerable amount, and ( 3 ) some elution solvents were possibly incorporated into the separated fractions. In quali tative analysis of pyridine by ir spectroscopy inherent were some inaccuracies due to the presence of skeletal vibration bands of condensed aromatic rings in the asphaltene. No marked difference, however, was found in the degree of removal of the following three types of nitrogen compounds: pyrroles, amides, and pyridines. Separation of the asphaltenes by GPC showed that, in the hydrotreatment, preferential decomposition of their lower molecular weight fractions took place leading to the significant decrease in their nitrogen contents. These fin dings would suggest that the rate of diffusion of large asphaltene molecules into the catalyst pores became rate determing, resulting in the equivocal difference among the reactivities of nitrogen compounds.

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The catalyst composed of Co (II), Ce (III) and the bromide ions showed the highest activity for the oxidation of o-xylene in acetic anhydride (Fig.1). The optimum conditions for the catalyst were surveyed (Figs 2-5). The oxidation of o-toluic acid and o-xylene under vario u s conditions (Table 1) revealed that the composition of the products was influenced by th e con centration of the substrates. The selectivity for phthalic anhydride over 3-acetoxyphthalid e increased with the decreasing concentration of o-toluic acid (Fig.7), o-xy l e ne (Fig.8), or phthalide (Table 1). The reactivities of o-toluic acid (Fig, 9) and o-xylene (Fig, 10) in the mixed solvents of acetic acid and anhydride were also studied. The increased rate and t h e extent of oxidation were observed when 25 vol% of acetic anhydride in acetic acid was employed.
o-Toluic anhydride (Fig.11), phthalide and 3-acetoxyphthalide (Table 1) which were consi dered as intermediates for the oxidation of o-toluic acid (Fig.6) were separately oxidized in acetic anhydride and the main oxidation path of o-toluic acid in acetic anhydride was show n as in Scheme 1.

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Photoisomerizationo f nerol to more useful geraniol has been carried out in the presence of acetophenone derivatives, halides, and thiols. p-Bromoacetophenone was shown to be an excellent catalyst in comparison with other acetophenone derivatives bearing hydrogen, fluorine or chlorine atom at the para-position. Other bromides such as bromotrichloromethanea nd 1-bromonaphthalene were also effective for the isomerization, although the reaction selectivity was low. The bromine atom produced by fission of the C-Br bond was presumed to be involved in the bromine-catalyzed reaction. Isomerization in the presence of thiols proceeded without an accompanying side reaction to give an equilibrium mixture of geraniol/nerol of about 60/40. The addition of radical-producing compounds accelerated the isomerization, suggesting that the reaction proceeded via an intermediate formed between the thiyl radical and nerol. Because of the high selectivity and the appreciable rate of the reaction even in bulk, the thiol- catalyzed reaction was concluded to be one of the most promising methods for industrial conversion of nerol to geraniol.

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The hydroxymethylation reaction of ammeline, ammelide, melam and melem, which are by product in the manufacture of melamine, was studied by the UV spectroscopic method. The absorption maximum shifted to longer wavelength side as the numbers of substituted hydroxy methyl group increased. The relationship between the reactivity for the addition of formalde hyde and the basicity constant of these compounds was also discussed.
In solution the maximum number of hydroxymethyl groups was equal to that of hydrogen atoms of amino groups substituted, while the number in solid state was about half of that in solution except melam. They were 4, 2, 6, 8 in solution and 2, 1, 3, 8 in solid state for ammeline, ammelide, melem and melam, respectively.
In Table 5, melamine was newly listed with the above discussed four compounds. These compounds were divided into the following classes; (1) all hydrogen atoms of amino groups were substituted by hydroxymethyl groups and (2) half numbers of hydrogen atoms of amino groups were substituted by hydroxymethyl groups. Melamine and melam belonged to class 1, and ammeline, ammelide and melem belonged to class 2. The compounds of class 1 had pK_b values only while these of class 2 had pK_a and pK_b values. The pK_b value of the latter was greater than that of the former.

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Effects of additives in radical graft polymerization of vinyl monomers onto 1, 2 and 1, 4polybutadiene were studied by using α, α'-azobisisobutyronitrile (AIBN) as an initiator in ben zene at 60°C. The grafting efficiency of vinyl monomers onto polybutadiene decreased in the order of acrylamide, methyl methacrylate (MMA), vinyl acetate and styrene. In the graft polymerization of MMA, the grafting efficiency and the degree of grafting increased by adding a small amount of Lewis acid (AlCl₃, ZnCl₂) but then decreased by further addition. In the graft polymerization of styrene, they increased with increasing the quantity of Lewis acid (AlCl₃, ZnCl₂). These results would be due to the complex formation between styrene and Lewis acid, which affects the graft polymerization. Complex formation between MMA and Lewis acid would accelerate both homopolymerization and grafting reaction. The order of the effect of Lewis acid on the degree of grafting and the grafting efficiency in the graft polymerization of styrene onto 1, 2-polybutadiene was as follows: ZnCl₂>AlCl₃>ZnI₂ Lewis base did not affect the degree of grafting and the grafting efficiency. In the graft polymeri zation onto 1, 4-polybutadiene, Lewis acid and Lewis base had little effects for the grafting efficiency and the degree of grafting. Zinc iodide retarded the graft polymerization.

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In order to ascertain the source and the form of mercury in urban ambient air, the behavior of mercury was considered over a period of two years by the determination of the mercury concentrations in ambient air and in total atmospheric particulate matters. From the deter mination, it became clear that when atmospheric temperature was high, i. e. in summer and in daytime, the mercury concentration in urban air was high and when the temperature was low, i. e. in winter and in nighttime, the mercury concentration was low.
On the other hand, it was found that the mercury concentration in a irborne particulates had a tendency to become low in summer and high in winter. This correlation proved to be the reverse against the mercury concentration in urban air. Namely, the behavior of mercury in environment could be explained as follows: when the temperature rose, the mercury was aesorbed from soil and airborne particulates and was isolated in ambient air as mercury vapo r: Moreover when the temperature dropped, the mercury in ambient air was deposited on the surface of the earth with dew and so forth.

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Amino acids are adsorbed on a mixed hydroxide of iron (III) and copper (II) at about pH 9and desorbed at above pH 13. The adsorption-desorption process of amino acids was studied in detail using tyrosine as a sample and the 50-fold concentration of tyrosine was adsorbed from its solution as low as 2x 10^-6 mol/l with the recovery of 96%. A suspension of the mixed hydroxide, which was prepared by mixing 10 ml of 1.0 mol/l iron (Jn) chloride and 10 ml of 1.0 mol/l copper (II) chloride, diluting the mixture to 100 ml with distilled water, and pre cipitating mixed hydroxide with sodium hydroxide, was added to 1 / of a sample solution containing 2 X10^-6 - X 10^-7 mol/l tyrosine. After adjusting the pH between 8.5 and 9.5, and the mixture was stirred for 40 min. The suspension was separated through filter paper (No.5C, φ 7 cm) under suction. The residue was dried at 100°C in an oven. Twenty milliliters of 0.5 N sodium hydroxide was added to the dried residue and stirred for 15 min. The recovery of tyrosine was determined spectrophotometrically with 1-nitroso-2-naphthol. The proposed method was applied to the concentration of other amino acids. The recoveries of amino acids were determined by the Ninhidrin method.

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A method for determing the trace amount of “methyl mercury” in sea water was studied using macroreticular chelating resins (RGS) containing epithio groups. The chelating resins were prepared by the reaction of the macroreticular glycidyl methacrylate-ethylene glycol dimethacrylate copolymer beads with ammonium thiocyanate dissolved in methaol.
Methyl mercury in sea water was favorably adsorbed on the RGS, w hen sea water was passed through the RGS column at the space velocity (SV) of 50 h^-1. Methyl mercury adsor bed on the RGS column was effectively eluted, when 10 bed volumes of 4 moll/ hydrochloric acid solution containing 0.5 mg/l of sodium thiosulfate were passed through the column at a SV of 5 h^-1 this procedure, inorganic mercury was not eluted.
Methyl mercury in the eluate was extracted first with ben zene and then with glutathione solution from the benzene phase. Methyl mercury in the glutathione solution was analyzed by the following method: the agueous solutions of sulfuric acid, sodium chloride and potassium permanganate were added to the glutathione solution, and then the solution was heated on a water bath for one hour. After cooling the solution, the amount of mercury was determined by a flameless atomic absorption spectrophotometry. The calibration curve for methyl mercury added to sea water was linear over the Hg concentration range from 0.05 ng/l to 0.5 ngl/l. The detectable concentration limit of methyl mercury by this method was 0.05 ng/l.
This method was successfully applied to the determination of methyl mercury in the sea water samples collected in Minamata Bay and the adjacent sea.

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The selective hydration of the C≡N bond of acrlylonitrile to form acrylamide was studied on various supported metal catalysts. Ethlyene cyanohydrin was also produced as a side product by the hydration of the C=C bond of acrylonitrile. The results of the reaction over supported Cu, Ni, Ag and Pd catalysts are shown in Table 1. Copper was found to be most effective for this reaction. Cu catalysts unsupported or supported on various oxides were tested (Table 2). The Cu catalysts supported on acidic materials (zeolite X, Y, SiO₂, celite, TiO₂)gave lower yield of acrylamide than the unsupported Cu catalyst, whereas those supported on basic materials (ZnO, MgO) showed higher activity. The highest yield of acrylamide was obtained by the Cu/MgO catalyst.

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The thermal decomposition of terbium (III) acetate tetrahydrate was studied by means of TG, DTA, X-ray diffraction, infrared spectroscopy, gas chromatography and chemical analysis. The dehydration begins at 60°C, and the course of dehydration completes at 180°C. One unknown lower hydrate is produced in the process of the dehydration. It is supposed that the unknown hydrate may be a O.5 hydrate. The anhydrous terbium (III) acetate demposes in the temperature range of 220-650°C to terbium (III) oxide, passing through two intermediate compounds. Presumably new intermediate compounds have compositions of TbOCH₃COO and Tb₂O₂CO₃, respectively.

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The magnetite was synthesized from the mixed solution containing Fe²⁺, Fe³⁺ and urea at about 100°C for 5 and 15 h, in the magnetic field of 0 or 10000 G. The magnetite synthesized under conditions of the 5 h period of reaction and no magnetic field was cube-shaped polycrystalline particles, whose average particle size, lattice constant, specific gravity, water content and saturation magnetization were 0.12, um, 8.39Å, 4.69, 4.47wt% and 88.3 emu/g, respectively. On the other hand, the reaction for 5 h in the magnetic field of 10000 G gave magnetite with the lattice constant of 8.40Å, specific gravity of 4.47, water content of 6.15 wt% and saturation magnetization of 81.6emu/g. Although the crystal linity of the latter magnetite was inferior to that of the former one, the SEM observation revealed that the cube-shaped particles were linked together in rows.

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The rate of isotopic exchange between thallium (I) and thallium (III) ions has been studied for elucidating the specific effect of sulfuric acid in the reaction. Measurements were carried out in NaClO₄-HClO₄ solutions, at 50°C, containing various amount of sulfuric acid. The rate constant thus determined changed linearly with the square of sulfate ion concentration, indicating that the BrOnsted-Bjerrum equation is applicable. It was concluded that the species responsible for the observed rate should be TlSO₄^- and TlSO₄⁺.

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Dimerization of alkyl vinyl ketones [1] in the presence of triphenylphosphine as a catalyst was studied. In the reaction of 1-penten-3-one [1a], 4-methylene-3, 7-nonanedione [5 a] was obtained. The dimerization of [1 b-h] gave dimers, 2-methylene-1, 5-dione derivatives [5b-h], in 42-85% yields. The reactions were considered to proceed through phosphonium betaine intermediates which attack the j9-carbon of the alkyl vinyl ketones as in the Michael type addition.

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The structure of one of the blue pigments formed by the reaction of o-acetylbenzophenone [1] with phenylhydrazine was determined by comparison with 1-(2, 3-dipheny1-1-isoindoly1)-2- (4-phenyl-1-phthalazinyl) ethylene [3 a] and its methyl iodide adduct. [3 a] was prepared by the reaction of 1, 2-diphenyl-3 (phenyliminomethyl) isoindole with 1-methy1-4-phenylphthala zine in the presence of potassium t-butoxide. [1] reacted with 2-aminoethanol to give blue pigment, C₄₈H₃₈N₂O₄ [5 ]. The mechanism for the formation of [5] is proposed as shown in Scheme 1.

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For the effective application of plam kernel shell and waste rubber wood, the conditions of activation of chars obtained from these starting materials were studied based on the observa tion of thier surface structures and their ash analyses. The electron microscope observation of the surface structures of starting chars showed that their porosities become lower in the following order; rubber wood charcoal>chip charcoal>coconut shell charcoal>palm kern el shell charcoal. The steam activation of these starting chars were carried out in a pilot rotary kiln, and adsorption\ characteristics as well as chemical composition of ash were examined for chars at the stages of starting, after activation, after water-washing and afer acid-washing. From the surface structure and ash analysis (ash content and chemical composition) of the starting chars, gas activation rate of rubber wood charcoal was estimated the highest, followed by chip charcoal, coconut shell charcoal, and palm kernel shell charcoal in this order. This was verified from the results of steam activation in a rotary kiln on a commercial scale.

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