The study on the thermal decomposition of β-alumina was made by X-ray single crystal methods. The thermal decomposition processes are characterized by a structural continuity reflected by the orientation relations. The orientation reatlons obtained were as folbows. (1)When the intermediate phase is formed, [001]β//[001]in.p.//[001]α[l00]β//[100]in.p.//[110]α (2)When the intermediate phase is not formed, [001]β//[001]α[100]β//[110]α The suffixes α, β and In. p. indicate α-alumina, β-alumina and the intermediate phase, respectively. The mechanisms of thethermal decomposition of β-alumina were discussed on the basis of the orientation relations obtained.

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The reaction of alkylphenols(2)with cyanuric chloride-DMF adduct has been investigated. When the reactions were carried out at 30-40°C, where cyanuric chloride reacts with DMF to give 1 : 2 adduct, the corresponding formates of (2)were obtained. On the other hand, at 60-70°C, N²-(alkylphenoxycarbony1)-N¹, N¹-dimethylformamidines(3)were obtained. The hydrolyses of(3)in dilute acidic ethanol gave N-formylcarbamates (5)or carbamates(6). Reductions of(3)with NaBH₄ in methanol afforded dimethylaminomethylcarbamates(7).

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The irreversible photofading of 1-aminoanthraquinones was found to be induced by the irra-diation of visible light in the presence of both aliphatic amines and benzyl halides (Tables 1, 2, Fig.1). The effect of oxygen on the photofading and kinetic studies (Figs. 3-5) suggested that the reaction was proceeded by the attack of benzyl halide on the reduced species such as radical anion or semiquinone radical of the quinones which were formed by amines in the reduction of the excited ³nπ* state of the aminoanthraquinones.

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The acid-catalyzed reaction of phenol with various organic peroxides was investigated to obtain such benzenediols as catechol and hydroquinone. Among the tested peroxides, “ketone peroxides”, obtained from ketones and hydrogen per-oxide, were found to give benzenediols in high yield. In the reactions, when catalysts such as sulfuric acid, perchloric acid, sulfonic acid, and sulfates were used, the molar ratio of catechol to hydroquinone formed was about 3 : 2, and when catalyst such as a mixture of clay and phosphoric acid was used, this ratio was 1 : 1. The reaction of substituted phenols with ketone peroxides was also investigated. The reaction was regarded as an electrophilic substitution one on the basis of the composi-tion of products and the quantum chemical calculation.

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New catalysts which promote selectively the α-sulforiation of anthraquinone in liquid sulfur dioxide [S0₂(1)] as a solvent were studied. Catalytic activity of transition metals was in the order : Pd>Ru>>Rh, and other metals such as Ti, Mn, Fe, Co, Ni, Cu, Mo, Ag, and Pb were entirely inactive. The activity of palladium compounds was revealed to be in the order: Pd(OAc)₂≥Pd-carbon>PdSO₄4, K₂PdC1₄, Pd(PhCN)₂CI₂, Pd(PPh₃)₂CI₂>>PdCI₂. In the case of the Pd-carbon catalyst, all the Pd-metal was found dissolved in the solution after the reaction. Reaction leading to α-sulfonic acid was much faster and more selective in SO₂(1) than in sulfuric acid ; e. g., a mixture of anthraquinone : SO₃ : SO₂2(1) ; Pd(OAc)₂=1 : 1.7 : 70 : 0.02 (molarratio) resulted in 100% conversion of anthraquinone after 3h heating at, and gave anthra-quinone ure gave a higher α-selectivity in contrast to the reaction in sulfuric acid. Reprecipitation of the solubilized Pd on carbon by hydrogen treating was also studied.

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Solvent Refined Coal, obtained from Akabira coal at 435°c, was separated by GPC and each fraction was analyzed by GPC, UV NMR, and osmometry (Figs. 1, 2, Table 2). These results revealed tiiat each fraction had a similar chemical structure to each other and the absorbance of UV at 260nm was about 4. 0 x10_-3g_-1 for each fraction. The height of the GPC elution curve was nearly proportional to the weight concentration at the elution volume. The. relationship between the properties of the produced SRC and the various coal liquefaction conditions was investigated for Akabira, Liddell, Taiheiyo coals. It was found that the depolymerization of the bridge structures between coal units was accelerated by raising the reaction temperature from 390 to 460°c (Figs. 3-5, Table 3). Prolonged reaction time from 30 to 120 min at 435°c increased not only the amount of depolymerization of the bridge structures but also the decomposition of coal units (Fig. 6, Table 4). Tetralin, hydrogen donor solvent, acted to stabilize the produced coal-fragment radicals and to hydrogenate the aromatic rings when its concentration was above 25% (Fig. 7, Table 4).

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Water-insoluble but hydrophilic fibers, such as cellulose, silk, and nylon, can polymerize some vinyl monomers in an inner part of a fiber. Water-soluble macromolecules from hydro-phobic areas (HA) in water. In this HA, radical vinyl polymerization takes place. This HA, as well as fiber, can be divided into hard and soft HA, acoording to their hydrophobicity. Similarly, vinyl monomers consist of hard and soft monomers. A hardness or softness of a monomer can be determined by its solubility in water. A new concept was proposed as fol-lows : A vinyl monomer having a certain hardness or softness becomes most easily incorporated into this HA, having corresponding hardness or softness. In terms of this concept, the following experimental results could be explained easily ; (1) Selectivity of vinyl monomers in uncatalyzed polymerization, ( 2 ) Unusual composition curves of the copolymer of MMA and styrene.

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The strong acid-type cation exchange resin was prepared by the sulfonation of phosphorus- containing novolak-type resin which in turn was obtained by the condensation of diphenyl phosphonate with formaldehyde. The ion exchange capacity of the dry cation exchange resin in the hydrogen form is in the range of 2-4 meq/g, depending on the conditions of sulfona-tion. The rate of ion exchange is rapid and, although the resin swells, the solution passes effectively through the resin column. The equilibrium distribution coefficient for eleven cationsin various hydrochloric acid concentrations using the sulfonated resin was measured. Ions Na⁺ and K⁺ loaded on a column can be separated from each other by elution with 0.15 mol/l HC1 and so does ions Cd²⁺ and Zn²⁺ with 0.40 molg HC1. The separation of Cr³⁺ from divalent metal ions is also possible by elution with 0.50 mol/l HC1.

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Syntheses of acryloguanamine (vinyl-1, 3, 5-triazine) and methacryloguanamine- (isopropenyl-1, 3, 5-triazine) by the reaction of unsaturated carboxylic derivatives with biguanide were inves-tigated in detail. Acryloguanamine was generally obtained in low yield from acrylic derivatives except acrylic anhydride. Alkyl methacrylates gave methacryloguanamine in satisfactory yield when it was treated with phenylbiguanide in such a dipolar aprotic solvent as dimethyl sulfoxide (DMSO) in the presence of sodium hydride. Further, it was rapidly obtained in 80-90% yield at a low temperature when such an active ester as phenyl or p-nitrophenyl metha-crylate was used. And also a pure methacryloguanamine was prepared in approximately quantitative yield in DMSO for 15 minutes by using methacrylic anhydride. On the other hand, it was found that a acrylo- or methacryloguanamines were readily synthesized by the reaction of acrylic or methacrylic acid with phenylbiguanide when using cyanuric chloride as an activating agent. By means of the above synthetic procedure, various methacryloguanamines, substituted by methyl and phenyl groups, were prepared in adequate purity and high yield.

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Deoderization of sulfur compounds by catalytic oxidation was carried out by a flow system with a fixed bed. Kinetics of the reaction and the activities of catalysts were studied with platinum catalysts supported on r-alumina in three forms ; granular Pt-Al₂0₃, honeycomb-shaped Pt-A1₂O₃ and aluminum tubular Pt-A1₂O₃, in the temperature range of 200-300°c. Thiophene was used as a main sulfur compound in low concentration range in order to examine the effect of the deoderization. For each catalyst the rate of the thiophene oxidation was zero order to the thiophene con-centration and the apparent activation energy was 16 kcal/mol. The activity of the honeycomb-shaped catalyst was the highest of the three catalysts. When the honeycomb-shaped catalyst was cut into halves and these were stacked upon each other, the activity was greatly higher than that of the original one-step honeycomb-shaped catalyst. The activity of the aluminum tubular catalyst was the lowest of the three catalysts, but the effect of the stack was obser-ved, as well as in the case of honeycomb-shaped catalyst. Furthermore, the order of activities of the three catalysts for the oxidation of dimethyl sulfide and diethyl sulfide was the same as for the oxidation of thiophene.

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The state of water in sludges has been studied in terms of NMR spectra. The samples used were aluminum hydroxide and an activated sludge. The latter was obtained from a standard artificial sewage. Water content of the samples was changed by evaporation at a room tern-perature and NMR spectra of the samples were measured with 100 MHz High Resolution NMR.The amounts of bound water in aluminum hydroxide and in an activated sludge were estimated to be 1.4 and 3.0 g/g of dry solid, respectively, on the basis of the relationship between water content and line width (Fig. 4). After the samples had been freezed and thawed, the mobility of water in aluminum hydroxide increased, whereas that in an activated sludge almost un-changed (Fig. 6 and Fig. 7). When the samples were heated, the mobility of water in both samples increased with rising temperature (Fig. 9). After the samples had been heated at 90°c for 0.5 h and cooled to 33°c, the mobility of water in an activated sludge almost returned to its original value. whereas that in aluminum hydroxide did not.

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The polarized absorption spectrum of sodium benzenesulfonate in a stretched polymer film was measured at -170°c, and the polarization of each vibronic band in the ¹L_b transition was determined. It has been found that the short axis polarized vibronic bands of ¹L_b are observed at 37040 (ν=0), 37990 (ν=a₁), 38940 (ν=2a₁) and 39890 cm^-1(ν=3a₁) and the long axis ones at 37660 (ν=b₂), 38610 (ν=b₂+a₁), 39560 (ν=b₂+2a₁) and 40520 cm^-1(ν=b₂+3a₁).

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Temperature dependence of solution properties associated with the clouding phenomena of aqueous solutions of a nonionic surface active agent, poly (oxyethylene) dodecyl ether (C₁₂H₂₅O(CH₂CH₂O)_9.3H), has been investigated on the analogy of the free volume theory for polymer solution proposed by Prigogine and advanced by Patterson and Flory. Consequently, while the second virial coefficient of the solution obtained by light scattering measurements was negative in the vicinity of the critical point (LCST), it was positive at lower temperature. These experimental results demonstrate the existence of a temperature at which the second virial coefficient is zero. According to the theory for polymer solution, this temperature corresponds to theta point, at which micelle-micelle, solvent-solvent and micelle-solvent interactions are equal. Further investigation revealed that θμ determined from temperature dependence of X₁ estimated from the heat of mixing by assuming regular solution agreed very closely with θι determined from temperature dependence of the second virial coefficient. In addition, the heat of mixing in the vicinity of the LCST was negative. These results suggest the applicability of the thermodynamic free volume theory, developed by Prigogine, Patterson and Flory on the LCST and UCST phenomena, to aqueous solution of nonionic surface active agents. In conclusion, the present results suggest the polymer-like behavior of the micelles of nonionic surface active agents in the aqueous solutions.

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Fluorescence behaviors of typical heteroexcimer systems in aqueous micellar solutions have been studied for the understanding of the mechanisms of photochemical charge transfer proces-ses in micellar solutions. Results obtained have been examined in comparison with those obtained for homogeneous solutions. Fluorescers such as pyrene, various pyrend derivatives and several other aromatic hydrocarbon systems, and quenchers such as N, N-dimethylaniline, sodium p- (dimethylamino) benzenesulfonate, dicyanobenzenes and 4-cyanopyridine were used. It was found that the aromatic hydrocarbon fluorescence was strongly quenched by those quen-chers, that the relation between the fluorscence yield and the quencher concentration greatly deviated from the simple Stern-Volmer equation and that the fluorescence decay curves under the presence of quenchers were not exponential. In all cases examined here, no heteroexcimer fluorescence was observed. The effect of the concentration of qtienchers on the relative fluo-rescence yields and on the fluorescence decay can be well interpreted under the assumptions that the quenchers are distributed over both micellar and bulk aqueous phases and that the distribution in the micellar phase obeys the Poisson statistics. This analysis shows that the fluorescence quenching in the heteroexcimer systems in, micellar solutions involves both the first order reaction process due to the charge transfer between the fluorescer and quencher trapped in the same micelle and the second order reaction process due to the interaction between the fluorescer trapped in the micelle and the quencher from the bulk aqueous phase. No generation of the heteroexcimer fluorescence for various aromatic hydrocarbon-N, N-dimethylaniline sys-tems including (1-pyreny1)-(CH₂)n-COOH (n=1-11), suggests that the interior of micelles is not composed of aliphatic hydrocarbon-like substances and that it has a very high polarity and a large amount of water. This is quite different from the behavior of bilayer liposomes in which a pyrene-N, N-dimethylanilne system shows heteroexcimer fluorescence.

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The solution states and conformations of Aerosol IB, AY and MA were investigated by surface-tension measurements, heat-of-dilution measurements and a ¹H- and ¹³C-NMR study, and compared with those of Aerosol OT. It was suggested that in water two hydrocarbonchains of Aerosol IB shorter than those of Aerosol OT aggregate with each other by hydrophobic interaction both in monomeric state and in micellar state as similarly as the chains of Aerosol OT. In chloroform, on the other hand, Aerosol IB has a different conformation from that of Aerosol OT. Aerosol IB has two steps in micellization or it forms the 1 st and 2 nd micelles (aggregates) . The 1 st micelle has an association number of 2 or 3. The 1 st CMC is about 0.2 mol.kg^-1. For the 2 nd micelle, the association number could not be determined exactly at present but estimated as less than 10, and the CMC was evaluated as 1 mol.kg^-1. The dynamic behaviors of Aerosol IB, AY and MA in monomeric state and micellar state were discussed on the basis of ¹³C-NMR spin-lattice relaxation time T1. The correlation time of micelles calculated from T₁ and the time from the viscosity of solvent agreed well with each other for the micellar shapes approximated to be ellipsoidal.

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Liquid membrane electrodes selective to surfactant ions were devised, and employed to thestudy of micellar solutions. In this study, a nitrobenzene solution of hexadecyltrimethyl-ammonium-dodecyl sulfate complex was used as the liquid membrane. The liquid membrane was much more permselective to dodecyl sulfate ions than to inorganic anions (cell B and Table 1). With the liquid membrane electrode, the membrane potentials for the bivalent-metal dodecyl sulfate solutions were measured in the absence as well as in the presence of inorganic salts (cell A and Figs. 2-6). The membrane potential vs. the logarithmic concent-ration of surfactants plots showed that the potential had a maximum at the critical micelle concentration, (CMC). Below the CMC, the membrane potential exhibited the ideal Nern-stian behavior, while above the CMC, it decreased with the increase in the concentration of surfactants. A simple thermodynamic consideration of a micellar solution based on the pseudo-phase model of micelle gave the degree of dissociation of micelle, α for Cu-, Co-, Mn-, and Mg dodecyl sulfates (Table 2). No appreciable difference was found among those values of α. The values were, however, about a half of that of the NaDS micelle. These results were corresponding to the facts that CMC's values and micellar association numbers in the various bivalent-metal dodecyl sulfate solutions were almost the same within experimental error. It has been deduced that the concentration of the singly dispersed surfactant ions above the CMC decreases with the increase of the total concentration of the surfactants unless a large excess of the electrolytes, such as CuSO₄, CoC1₂, MnSO₄, and MgC1₂, is added to the surfactant solution, and that the degree of dissociation of the micelle is unchanged in that case even when the excess electrolyte is present.

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It is known that the tautomerism of benzoylacetanilide (BZAA) shifts to the ketonic form in aqueous phase, but lies on the enolic form in nonaqueous media or in the micelle of sur-factant. This phenomenon can be used to study the effects of inorganic salts and urea on the mode of packing of the micelle of nonionic surfactants. The increase in the packing of sur-factant molecules in the micelle makes the inside of the micelle behave like a nonpolar solvent and causes an enhancement in the intensity of absorption spectra of the enolic form. Using the keto-enol tautomerism of BZAA, it was shown that the micelle of a homogeneous hepta- ethylene glycol dodecl ether (7 ED) increased in the compactness with the addition of KNO₃, KBr, KC1, and K₂, SO₄, and decreased with the addition of KSCN and urea. Furthermore, the change in the cloud point of 7 ED by the addition of salts and urea was found to corres-pond fairly well to the degree of enolization, consequently to the change in the packing of 7 ED monomers in the micelle. These results coincided with those obtained by the charge-transfer interaction between the nonionic surfactant and 7, 7, 8, 8-tetracyanoquinodimethane in a solubilized system.

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Four N-(long-chain alkyl) -N- (2-hydroxyethyl)-2-aminoethanesulfonic acids were synthesi-zed. Surface tension and electric conductance for these compounds were measured in aqueous solutions. Emulsification power was also tested for the water-liquid paraffin system. Further-more, these compounds were tested for the acid-base buffer capacities and antimicrobial activity against a gram-positive bacterium, Staphylococcus aureus, a gram-negative bacterium, Escheri-chia coli, and a fungus, Aspergillus oryzae. Surface activities (lowering of surface tension and emulsification power) increased with increasing alkyl-chain length. This relationship also held for the antimicrobial activities, the tetradecyl derivative being found most active among the tested compounds. To the contrary, the buffer capacity decreased with increasing alkyl-chain length.

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An amphiphilic polymer (3) was prepared according to Scheme 1 from glucose and (chloro-methyl) styrene as starting materials to develop a new type of speciality polymers having sugar as the pendant group. The structures of (3) and its precursor (2) were established from IR, ¹H- and ¹³C-NMR analyses. It was suggested from the solution properties, particularly the viscosities in water and in DMSO that (3) was in a tightly-coiled conformation in water. A. spectrophotometric investigation revealed that Methyl Orange was strongly bound to the hydro-phobic region of (3) in water. Binding constants were determined by the methods of Benesi-Hildebrand and Klotz as shown in Fig. 7 and 8, respectively, and were found to be higher than those of poly (N-vinylpyrrolidone), which had been reputed to bind organic solutes most strongly among nonionic polymers. Intramolecular aggregation of the hydrophobic vinylbenzyl residues was considered to be responsible for the formation of a kind of polymer micelle.

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In order to elucidate the mechanism of the interaction between ether type nonionic surfac-tants and anionic dyes, cloud points (CP) were measured for the solution containing deca-(oxvethvlene) nonylphenyl ether (NP 10) and sodium 1-phenylazo-2-naphthol-6-sulfonateerivative (D), in the absence and presence of sodium chloride, where the concentration of NP 10 was above CMC and NP 10-D mixed micelles were considered to be formed in the solution. Furthermore, w the solutions were allowed to stand at the temperature aboNie CP, for 8 hrs. As a result, three kinds of distinctly different regions, I, II and III were observed ; in the region I, where the temperature was below CP, the solution was completely transparent, in the region II, where the temperature was above CP, the volution was turbid, the fine particles in the solution being quite stable, and in the region III, where the temperature was also above CP and the concentration of added sodium chloride was considerably higher, the fine particles were aggregated with a coacervate layer being separated from the solution within 30 mins. In the regions I and III, where the amount of free dye and mixed micelle formed in the solution could be estimated by spectrophotometry, the standard enthalpies (ΔHI, ΔHIII) and entropies (ΔSI, ΔSIII) for the interacting species of NP 10 micelle and D were determined in the presence of sodium chloride. It was found that the values of the enthalpies and the entropies were negative. Moreover, from the fact that -ΔSI<ΔSIII), the mixed micelle (coacervate) obtained in the region III was deduced to be in an ordered state as compared with that in the region I.

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As a basis of molecular: aggregate:: electron transport-sensitizers, micelle structure was spe-ctroscopically studied by using following surfactants containing anthryl or benzoylphenyl group. These were sodium 10-dodecy1-9-anthrylraethanestrifenate-(SDAS), (p-benzoylbenzyl)-triethyl-ammonium bromide (BBTEABr), (p-benzoylbenzyl) dodecyldimethylammonium bromide (BBDD-ABr), sodium 10-(4-behigylphenoxy)-decane-1-sulfonate (BPDSNa) 'sodium, 6(4-benzoylphen-oxy) -1-hexane' sulfpnate (BPHSNa), and [10-(4-bermoylplienoxy)deol]oimetylammonium bromide (BPDTABr). Even below CMC; the anthryl groups..isi SDAS aggregated to form a stable dimer-like structure (Figs, 3, 6(a), and Tablel 1). Above, CMC, however, aggregation of anthryl groups became Iooser ; that was expected to result in a favorable micelle structure to mimic therole of antena pigmeritsby promoting energy migration amOng_.anthril groups. The measurements of π-π* and n-π* transitions of benzoylphenyl groups (Fig.7 and Table 4) indicated-that :lienzpylphenyL grpups were located in the polar boundary layer of the micelles regardless of the structure of surfactants. The structures of the micelles containing benzoyl-phenyl or anthryl group were schematically shown (Figs. 8, 9) based on spectroscopic inf or-mation.

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2, 6-Dichloro-4-alkyl(or alkoxy) -1, 3, 5-triazines derived from cyanuric chloride were treated with equimolar tetra- and hexaethylene glycol dianions in toluene to give two series of 1 : 1 macrocyclic polyethers, (1) and (2), respectively. Cloud point, critical micelle concentration (CMC), surface tension at CMC (γcmc) and cata-lytic action on the reaction of octyl bromide with saturated aqueous potassium salts were examined for these macrocycles. The data were compared with those of known crown ethers ((3), (4), (5) and (6) and of linear poly (oxyethylene) surfactants ((7), (8)) and poly-ethylene glycol monoalkyl ethers). Higher homologes of (2) were soluble in water. Their cloud point, CMC and γcmc decre ased with the increasing alkyl chain length. With respect to these properties, (2) seemed to be equivalent to (3) and (4) having the same alkyl chain (Table 2). The CMC of (2) was rather higher than that of linear polyethers (7), although (2) had, much lower cloud point compared to (7) (Figs. 3, 4). The catalytic efficiency of (2) increased with the increasing alkyl chain length. When the catalytic action was compared among all series examined, the efficiency appeared to increase in the order : (1)<(5)<<(2)<(7)<(8)≤(6) (Tables 3, 4). The role of crown compounds in surfactant properties and the relation of surface activity to cataivtin antinn were discussed on the basis of the results obtained here.

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The carrier effect of reversed micelles of sodium or barium 1, 2-bis(2-ethylhexyloxycarbony1)-1-ethanesulfonates (NaOT or BaOT) and didodecyldimethylammonium bromide (DDAB) was studied on aminolysis of p-nitrophenyl acetate (PNPA) by alkylamines and imidazole in anhy-drous apolar solvents. The carrier effect which can be estimated from the difference between the rate constant in micellar solution and that in pure solvent was much marked (Tables 1, 2), The effect by DDAB micelle was higher than by NaOT or BaOT (Table 2). This can be elucidated by higher interaction of alkylamines and imidazole with DDAB than NaOT or BaOT. However, no correlation between the carrier effect and the magnitude of interaction was observed in the reaction systems of primary amines/NaOT and hexylarnine/NaOT or Ba0T.The carrier effect for aminolysis of PNPA by propylamine or histamine and for hydrolysis of PNPA by imidazole was also examined as a function of concentration of water solubilized by NaOT in cyclohexane (Fig. 6). The effect at higher concentration of water was elucidated in relation with the formation of microemulsion.

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Proton abstraction from β-(p-nitrophenoxy)propiophenone(β-NPP(5)) catalyzed by hydro- xamate(C₁₂-BHA (6) chol-HA(7)) and imidazole(cholest-Im(8)) anions was studied in the presence of aqueous aggregates of single-chain (CTAB(1)), dpuble-chain(2CnN⁺2C₁(2), n=12-18) and triple-chain (TMAC(3)) ammonium amphiphiles. These three types of ammonium salts gave rise to quite different aggregate morphologies, as "shownin Table 1. The rates of the base-catalyzed proton abstraction were enhanced by 100-4000 foldS in the presence of these hydrophobic aggregates (Figs. 2, 3). The extent of rate-enhancements was drastically changed by the combination of the anionic reagents and the cationic aggregates. The long-chain hydroxamate(C, -BHA): showed proton- abstraction reactivities which reflected the hydrophobic microenvironment of the respective aggregates TMAC(3)>2CnN⁺2C₁>CTAB(1). Cholic acid-derived hydroxamate (chol-HA) showed a small reactivity in the ammonium bilayer membranes, probably because it did not fit in the: bilayer structure (Table 2). The rate of proton abstraction by C₁₂-BHA(6) in 2CnN⁺2C₁, bilayer aggregates was con-siderably influenced by the phase-transition (Table 3) of the bilayer, as shown in Fig. 5. In contrast, the corresponding change was not observed in the case of spontaneous (hydroxide-catalyzed) proton abstraction.

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The kinetics of hydrolysis of γ-valerolactone in aqueous solution in the presence of cationic, anionic and nonionic surfactants, NaC1, and Na₂SO₄, were studied at 0.0, 2.5 and 5.0°c. From the rate constant (kobs), In PZ and the other thermodynamical parameters were evaluated for each type of the surfactants. As the rate of hydrolysis was slightly increased by the addition of the above surfactants, E_A, ΔS_A and In PZ were decreased. While ΔF_A remained unchanged as compared with the case of no addition of the above surfactants. A linear relationship between E_A and ΔS_A as well as ΔS_A and log CMC, was observed. Enhancement effects of the surfactants were observed in the following : cationics>nonionic (PONPE 30)>anionic (SDS), NaCl, Na₂SO₄ none additive>anionic (SDBS)>nonionic (PONPE 15). From the results mentioned above, it is concluded that the substrate and OH^- were slightly concentrated at the micelle, followed by the decrease in the rate of hydrolysis.

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Hydrolysis and aminolysis of p-decyl, p-butyl and unsubstituted phenyl phosphatosulfates (DPPS, BPPS and PPS) were examined. In water, DPPS formed a micelle (CMC=1.6x10^-3 mol/l, 39.5°c). The micellar rates of hydrolysis of DPPS (2X10^-2mol/l) in the presence of sodium dodecyl sulfate (6x10^-2mol/l) were measured for a wide range of pH (2-14) and compared with the corresponding non-micellar rates of PPS (Fig.3) . The resulting pH-rate profiles were analyzed to give the rate constants, k_H+, k_m, k_o, k_OH- and the kinetic acid disso-ciation constants, K_a of monoanionic species. The results indicate a fairly large micellar rate acceleration for the acid hydrolysis (k_H+, k_m), no effect for the neutral hydrolysis (k_O), and micellar inhibition for the alkaline hydrolysis (k_OH-) Micellar rate acceleration of 1.7-13 fold was also observed for the aminolysis of DPPS and PPS.

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In deacylation of 3-nitro-4-(acyloxy)benzoic acids (S₂^--S₁₆^-), p-nitrophenyl carboxylate (S₂-S₁₆) and N-acylphenylalanine-p-nitrophenyl esters (DL-, D- or L-S_n : n=2-16) with N-acyl-L-histidine (AcetHis, OctHis, LauHis, and PalHis) in the presence of cationic micelles (CTAB or CBzAC), the increase in acyl chain length of the nucleophiles enhanced the catalytic activity of the micelles. The selective deacylation of substrates (S₁₂^-, S₁₀, DL-S₁₀, D- or L-S₁₀, etc.) with appropriate acyl chain length was also enhanced by approximating the substrates toward the nucleophiles through hydrophobic interaction between the substrate and the cationic micelles. The deacylation rate of DL-, D-, or L-S_n(n=2-16) was remarkably enhanced by the above micellar catalysts as compared with that of S_n^- or S_n (n=2-16). This fact is attributable to approximation effect induced by hydrophobic interaction between the phenyl of amino acid ester (substrate) and imidazolyl (nuccleophile) as well as by the bonding (-C=O···H-N-) between the amide bonds of the both species. It is noteworthy that the N-acyl-L-histidine and CTAB system resulted in the maximum deacylation rate for the D- and L-S₁₀ enantiomers involving same acyl chain lengths (L-S₁₀ was changed into L-S₁₂ by the PalHis-CTAB system) with the largest enantiomer rate ratio. Especially, in the deacylation of D- or L-S_n (n=2-6) with the comicelles of LauHis- or PalHis-CTAB, the deacylation rate of L-S₁₀ (or L-S₁₂) was found to be 2.6-2.8 times as higher as that of D-S₁₀ or D-S₁₂. These experimental findings might lead to a conclusion that the stereoselection of a specific enantiomer such as L-S₁₀ in the deacylation of D- and L-S_n (n=2-16) is mainly due to the following factors : (a) the selective incorporation of the substrate with an appropriate acyl chain length by the micellar catalyst, and (b) the predominant approximating effects of the hydrophobic substrate-nucleophile interaction, which was mentioned above, and the hydrogen bonding for one of substrate enantiomers.

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Acidic hydrolysis of nucleosides such as adenosine, guanosine and inosine in the presence of surfactants was investigated. There is no effect by the addition of a cationic surfactant, hexadecyltrimethylammonium bromide, on the rate of hydrolysis, while the addition of an anionic surfactant, sodium dodecyl sulfate, enhances the hydrolysis rate of N-gulcoside linkage of the nucleosides. The extent of enhancement depends on pK_a value of the substrates. From the measurements of fluorescence spectra of adenosine and guanosine, the site of incorporation of the nucleosides into micelles was discussed. The hydrolysis rate of phosphoric ester linkage of nucleotides such as AMP and IMP was also measured. In the reversed micellar system of dodecylammonium propionate-hexane, the hydrolysis of ATP or ITP is enhanced by the addition of metal ions such as Mg(II), and the degree of enhancement is affected by the nucleotides.

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Investigations of the effect of controlling the mobility of reactants placed in a extremely restricted field on the reaction rate and/or path are significant in connection with understanding of the microenvironment effect in biological systems such as the reaction pocket of enzymes, biomembranes, and interior of celles. From this point of view, the acid-catalyzed and non-catalyzed reactions of hydrazobenzene-3, 3′-disulfonic acid (HYD) in the cationic HTAB reversed micelles have been studied.
In the HTAB micelles containing a small amount of perchloric acid, rapid benzidine rearrangement of HYD took place with a concomitant formation of azobenzene-3, 3′-disulfonic acid (AZO) by the autoxidation of HYD. With the increase in the acid concentration, the autoxidation was depressed and the benzidine rearrangement predominantly proceeded. In the similar micellar systems without any catalytic acid, only the autoxidation of HYD to AZO exclusively occurred. Under both conditions, any of semidines and disproportionation products was not detected. These results present a possibility that in the extremely restricted field as provided by reversed micelles, not only the reaction rate but the reaction path also are controlled.

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The complex formation of phenothiazine with bivalent metal ions was examined spectrophotometrically in the surfactant micellar solutions of bivalent metal alkyl sulfates (M(C₁₂H₂₅OSO₃)₂; M=Cu²⁺, Mg²⁺, Mn²⁺, Co²⁺, Ni²⁺), where the bivalent metals constituted the counter ions of micelles. Every counter ion formed a complex with phenothiazine. The complexation reaction of Cu²⁺ ion was much faster than the others and the reaction obeyed the apparent first-order kinetics whose rate constant (k₁) was 3.0×10^-5 sec^-1. The characteristic wavelengths at absorption maxima of the M-phenothiazine complexes were in the ranges of 460-470nm and of 650-670nm, the respective molecular extinction coefficient (ε) being 4.35×10² at 650nm and 6.15×10²m²mol^-1 at 660nm for Cu²⁺- and Mn²⁺-complexes. From spectral changes of phenothiazine in the micellar solutions, the location of solubilized phenothiazine was found to be in the outer hydrophobic part near the micellar surface so called the palisade layer rather than in the micellar interior.

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Photoinduced electron transfer reactions (Schemes 1 and 2) of tris(2, 2′-bipyridine) ruthenium (II) ion, Ru(bpy)₃²⁺, and its amphipathic derivative (RuC₁₂B²⁺) were investigated in various micellar systems. For benzyl viologen sensitized by the ruthenium complex enriched on the micellar surface of an anionic surfactant (Ru(bpy)₃²⁺[CH₃(CH₂)₁₀COO^-]₂), the photoreduction in miccllar systems showed an unexpectedly high rates in comparison with the rates in nonmicellar system (Figs. 2 and 3). The RuC₁₂B²⁺ ion incorporated in CTAC micelles afforded a system with a very efficient charge separation for the photoactivated ruthenium complexes. In the presence of NTA, the reductive quenching easily proceeded to yield Ru(bpy)₃⁺, which was found to be used as an efficient catalyst for the reduction of 9, 10-anthraquinone-1-sulfonate (Table 3). The oxidative quenching of RuC₁₂B²⁺ by methyl viologen on CTAC micellar surface was retarded by coulombic repulsion, while *RuC₁₂B²⁺ was readily oxidized in the same micelle by amphipathic homologue of viologen (2C₁₂V²⁺) (Table 2). The oxidative quenching of *RuC₁₂B²⁺ by 2CnV²⁺ was further enhanced in bilayer molecular assemblies consisting of ammonium salts (2C₁₂NB) with two long alkyl groups (Table 4). The rate of sensitized photoreduction of 2CnV²⁺ homologue also increased more in 2C₁₂NB than in CTAC (Table 5). The ruthenium complexes incorporated at micellar surface thus proved to serve as good photoinduced redox catalysts.

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Dye-sensitized electron transport through the phospholipid wall of a single wall liposome system was studied in the presence of several redox dyes. The experiments were carried out in the single wall liposome system that contained the electron acceptor (K₃[Fe(CN)₆]) only in the inner aqueous phase and the electron donnor (sodium ascorbate) only in the outer aqueous phase. The reduction of K₃[Fe(CN)₆] accompanied with the trans-membrane electron transport was observed even in the dark for the dye with higher redox potential than that of ascorbate. Though the redction of K₃[Fe(CN)₆] was not observed in the dark for the dye with lower redox potential than that of ascorbate, it was induced by light irradiation. The electron transport observed here was completely coupled with the redox cycle of the dye, and the dye was recycled in the course of the electron transport reaction. These electron transport experiments were carried out both in the irradiated and non-irradiated system without using any quinones or carotenes.

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For designing a system which might effect the conversion of light energy into chemical energy through a coupling of photoredox reactions across membrane, we prepared a dispersion of phosphatidylcholine bilayer liposomes containing chlorophyll a.
The concentration change of Cu²⁺, [Fe(CN)₆]^3- or O₂ in the solution of outer compartment was measured during illumination with the light absorbable by chlorophyll a by the use of ESR, ion selective electrode or oxygen electrode.
The enhancement of the photoreduction of Cu²⁺ by a reductant such as potassium ascorbate localized in a solution of the opposite side of the membrane suggested that photoredox reactions at both the membrane-solution interfaces of a liposome were coupled through the bilayer. Kinetic analysis of the reactions based on a possible reaction scheme was carried out and some of kinetic parameters were determined.
The photo-induced consumption of [Fe(CN)₆]^3- or O₂ in a solution of outer compartment was observed without addition of a particular reductant to the system. The reaction rate was strongly affected by the addition of carbonyl cyanide m-chlorophenylhydrazone (CCCP) to the dispersion. The O₂ consumption was supressed by the existence of [Fe(CN)₆]^3- in a solution of the inner compartment. These facts suggest that the photoredox reactions at both the membrane-solution interfaces will be coupled in this case, through electron transport facilitated by the addition of CCCP across the bilayer membrane.

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Phosphatidylcholine (PC) vesicles were prepared by a sonication method in the system not involving any kinds of buffers. For the buffer-free vesicles, the following physical parameters were determined by electron microscopy and sedimentation velocity measurements : S₀=2.15×10^-13/sec, D₀=2.03x10^-7cm²/sec, 2a=24.04nm and M=2.22x10⁶g.
The buffer-free vesicles were quantitatively flocculated with "trimethylammonium glycol chitosan" iodide (TAGC) over the pH region of 3-12. Analysis of the aggregates revealed that the flocculation would be based on the salt-linkage formation between phosphate group of PC and trimethylammonium group in TAGC. In order to obtain a more insight into the flocculation mechanism, the enthalpy (ΔH_m) of the interaction between PC vesicles and some kinds of polyelectrolyte ion was measured by a microcalorimeter technique. Consequently, the ΔH_m for human serum albumin and poly-L-lysine was found negative, but positive (i. e., endothermal) for TAGC, entropic factors thus being of dominant importance.

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Uniformly sized L-a-dipalmitoylphosphatidylcholine liposome dispersions were prepared in different molecular weights ranging from 2×10⁶ to 3×10⁷ daltons by means of molecular sieve column chromatography on a Sepharose 2B gel in order to investigate the static and kinetic behaviors of the phase transition of the single lamellar liposomes.
The phase transition was monitored by the fluorescence intensity of N, N′-dioctadecyloxacarbocyanine incorporated in the liposomes. The single lamellar liposomes exhibit only single transition which depends on the liposome size. Decrease in the liposome size results in the drop of the transition temperature and in the decrease of the cooperativity of the transition.
The rate of the phase transition was also studied by the temperature-jump method as a function of the liposome size. The relaxation is characterized by single process and its time constant exhibits a maximum at the midpoint of the transition. The maximum values increase with increasing size of the liposomes. Theoretical results obtained from a kinetic model based on two-dimensional Ising lattice were compared with the experiments.

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The interaction of sodium chloride with zwitterionic N-octylbetaine in aqueous solution was studied by proton spin-lattice relaxation time measurements above and below the critical micelle concentration of surfactant. The binding constant of sodium chloride to molecularly dispersed surfactant is far larger than to surfactant micelles. A model of two dimensional pseudo-ionic lattice structure (Fig. 3), which we have previously proposed for ampholytic phospholipid monolayer, is also applicable to the three dimensional molecular aggregates of zwitterionic surfactant.

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