Static and dynamic light scattering and pulsed-gradient spin-echo (PGSE) have been measured on aqueous solutions of nonionic surfactants in order to elucidate aggregation behaviors of amphiphiles in a wide concentration and temperature range. In "dilute" region (-1 wt%), temperature dependences of intermicellar interactions and micelle size distribution is discussed on the basis of the ratio of the mutual and self-diffusion coefficients. It is shown that micelles grow with increasing temperature above about Tc-30 K (T: the critical solution temperature)and effects of critical concentration fluctuations become important only above about Tc-4 K. In semidilute region (1-30 wt%), light scattering results have been analyzed by using the scaling theory for entangled solutions of flexible polymers which exhibit phase separations. The results suggest entanglement of elongated micelles above about Tc-15 K. The PGSE data in this region can be explained by a simple model which takes into account the intermicellar exchange of surfactant molecules. Similar measurements have been made on mixed anionic/cationic surfactant solutions. Light scattering results indicate that micelles grow with the decrease in the total surfactant concentration. A method is proposed for determining the composition of mixed micelles from PGSE data. It is shown that the micellar growth comes from the change in the micellar composition.

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For developing of polyacrylonitrile based activated carbon fiber (PAN-ACF) having high mesopore volumes, the effects of ash in oxidized fiber, acid treatment and atmosphere in activation were investigated on the mesopore volumes (mesopore: pore radius 20-400A) and adsorption capaciies of vitamine B12. The activation of oxidized fiber containing titanium (W) oxide (0.1 %) was found to increase the mesopore volume and adsorption capa city for vitamine B12. When PAN-ACF containing titanium(1V) oxide was further treated with 1.5%aqueous solution of hydrochloric acid, nitric acid, sulfuric acid and mixed acid (hydrochloric acid/nitric acid 3/1), the fiber with specific surface area (SA) more than 1000 m2/g was greatly affected by hydrochoric acid and, nitric acid and mixed acid. With reactivation of PAN-ACF (SA: 950 m2/g) by carbon dioxide at 900 °C, . PAN-ACF having high mrsopore volumes were obtained at high specific surface areas.

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Cation-exchange capacity (CEC) was decreased by heating nickel montmorillonite. Ion exchange of nickel montmorillonite, hydrothermally treated, in a ZrOC12.8 H2O solution revealed the restoration of the decreased CEC. The degree of the restoration varied with the conditions of hydrothermal treatment, such as temperature and time. For example, the CEC of nickel montmorillonite heated at 300 °C for 1 h was restored to be O.89 meq/g by hydrothermally treating at 150 °C for 5 h, and to 1.09 meqfg at 200 °C for 5 h. The observed results indicate that the CEC of nickel montmorillonite can be decreased by heating the clay and restored by treating hydrothermally the clay.

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Chromium monoboride CrB was prepared by reaction between chromium and amorphous boron powders together with halides at 500-4300°C for 2 h in an argon atmosphere, in order to study the influence of halides on the temperature of reaction start and particle size of the system. When the atomic ratios of the starting materials were B/Cr =1.04 and X/Cr =O.02(X = NaC1, KC1 or KI), the formation of CrB began at 600 °C for 2 h, which is 300 °C low er than in the case of no additive. When halides were added, the relative X-ray intensity of CrB at 600-1300 °C became stronger than in the case of no additive. When halides were not added, the product at 1300 °C was coarse sintered particles with a grain size of about 2 pm in diameter. When NaC1 was added, sintered particles with a grain size smaller than 1 pm in diameter were obtained. When KC1 and KI were added, the products obtained were more sintered and, the grain size was larger than in the case of NaC1as additive. The effects of additives on sintering and grain growth of the products obtained by the reaction at 1300 °C was KI>KC1>NaCl. The lattice constants of the CrB formed in the presence of halides are as follows: with NaC1 additive: a =2.9640( 1 ) A, b=7.878 ( 1 ) A, c=2.932 ( 1 ) A, V=68.5 ( 1 ) A; with KC1additive: a = 2.970 ( 1 ) A, b=7.8 71 ( 1 ) A, c=2.928 0( 1 ) A, V=68.4 ( 1 ) A3; with KI a dditive: a=2.970 ( 1 ) A, b=7.865 ( 1 ), c=2.929 ( 1 ) A, V=68.4 ( 1 )A3.

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Single phase crystalline fine particles of the (Cr1_sTi5)203 solid solution have been synthesized by vapor-phase explosive reaction of CrO2C12--TiC14-H2 system ignited by a single laser pulse. The distribution of particle size was uniform with a mean particle size of 35 nm. Lattice constants of the (Cr1_xTi5)208 have been determined accurately by the Whole-powderpattern decomposition (WPPD) method. The axes lengths of the hexagonal unit cell of the oxide increase linearly with increasing Ti mole fraction x. The c axis of (Cr11Ti5)208 has larger expansion than the a axis. The crystal structure of the (Cr1_sTix. )203 was studied by the Rietveld analysis.

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Lithium niobate thin films were prepared on heated substrates by metal-organic chemical vapor deposition from dipivaloylmethanato lithium [Li(C111-11902)] and trichlorobis(dipivaloylmethanato)niobium(V) [Nb(C111-11902)2C18u] nder a reduced pressure of 5 Torr. In preliminary experiments, deposition behavior of Li20 and N13205 films from the respective sources was examined separately. The main reaction in Nb205 deposition was pyrolysis of [Nb(C11H19O2)2Cl3], whereas Li20 deposition involved the oxidation of [Li(C11H1902)]. The deposition rate as well as the chemical composition of LiNbO3 films were controlled by adjusting the source temperature and carrier gas flow rate. Stoichiometric LiNbO3 films with a single phase of trigonal structure were obtained when the deposition rate ratio [r=R(N13205)/R(Li20)]was controlled to be 0.4 in molar ratio at 625-650 °C under the conditions of a total gas flow rate of 300 m//min and an oxygen concentration of 50%. The films were preferentically oriented along (012) face on Si (100) substrate, while epitaxially grown films were deposited on LiTa08 (001) substrate.

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Size-exclusion chromatography (SEC) of DNAs was investigated with stainless steel columns (6 mml. D. x 250 mm) packed with macroporous spherical gels prepared from glucomannan. High molecular weight DNAs (>15 kb) were eluted following size-exclusion theory from the columns packed with large gels (>130 earn). However, the smaller gels resulted in the larger elution times for those DNAs. The particle size as well as the pore size of the packing material were found to be important factors for chromatographic separation of high molecular weight DNAs.

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In order to develop a sensitive and selective method for determination of lactone, a CO2supercritical fluid (SCF)-FIA system was designed using a chemiluminescent (CL) reaction between acetone and lactone. The flow system is comprised of a single line; the high pressure pump (LC-6 A, Shimadzu) for SCF, two sample injector (S, for CL reagents, 100 ft/; S2 for sample, 20 u/: Rheodyne 7125, USA) and detector (LUMI-FLOW 800, Nition) were set up on the line. The sample, lactone dissolved in acetone, was introduced into CO2-SCF for the carrier of FIA by a manual method considering the reasonable injection intervals. The CL is produced through a CL reaction between acetone and lactone in CO2-SCF; initiated by a production of excited acetone in the SCF. The analytical characteristics were as follows. Lower detection limit and limit of determination: 1. Ox M and 1.0 x 10- O x 1076 M by a 20 u/ injection method, respectively, RSD: 2.3% for 5 repeated runs of 1 x 10-7 M rbutyrolacton. e, analytical time required: 6 s. The proposed method was highly selective to lactone; water produced a strong CL quenching. Lactone in butter was analyzed by the proposed method.

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Bis(O-p-isobutylbenzylidene)sorbitol (i-BuBS) was synthesized from D-sorbitol and p isobutylbenzaldehyde, and the positions of two acetal-rings carrying each benzylidene substi- tuents and the conformation of two 1, 3-dioxane rings were made clear. The product obtained from i-BuBS by oxidative cleavage followed by reduction was proved to be 1, 3: 2, 4-bis(O-p-isobutylbenzylidene)xylitol (i-BuBX), which gave meso-xylitol: after hydrolysis. These products were identified by the analyses of 1H-NMR, GC-MS, specific rotation, and melting points. These results exhibite d that acetalization occured at 1, 3- and 2, 4-positions of D-sorbitol. Next, by the analysis of 1H-NMR data of i-BuBS it was disclosed that p-isobutylphenyl substituents occupied the equatorial position and two 1, 3-dioxane rings were connected in a cis-O-inside way. The molecular mechanics of force field calculation supported this structure and further revealed that the two aryl rings had the tortion angle 0, and 0, - of 130 and 71degrees, respectively, in the most stable conformation of i-BuBS. The positions of acetalization as well as the cis-junction of two dioxane rings are reasonable by considerin the structure of D-sorbitol.

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The reactivity of the amino group in S-thiocarbamoyl-, S-aroyl-, and S-(N-phenylbenzimidoyl)thiohydroxylamines ( 1 ), ( 2 ), ( 3 ) were examined. Their benzoylation by benzoic anhydride and condensation with benzaldehydes were performed in order to compare the reactivity with other amino compounds such as amines and carboxamides. Though they are less stable thermally and sensitive to acids, the corresponding N-benzokl derivatives (5 a, b), ( 6 ) and a number of novel imine componds (7 a--'d), (8 ah), (9 ac) were given even under mild conditions in fair yields, respectively. This fact suggests that the amino group of these thiohydroxylamines are more reactive than that of carboxamides. The imines ( 7 ), derived from ( 1 ), were found to have characteristic affinity for silver salts to form 1: 1 adducts (10 a -'c).

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The reactions of 1-indanone 1 a or 3, 4-dihydro-1(2 H)-naphthalenone (1 b) in carboxylic acid anhydrides (acetic, propionic and butanoic) in the presence of sulfuric acid afforded the corresponding 3-substituted 5 H-indeno[2, 1-e][1, 2]oxathiin-4(3 H)-one 2, 2-dioxides [3 a, 2 c and 2 d], and 3-substituted-5, 6-dihydronaphtho[2, 1-e][1, 2]oxathiin-4(3 H)-one 2, 2dioxides (3 b, 2 e and 2 f), respectively. On the other hand, the reaction of 1 a or 1 b with acetic anhydride in the presence of sulfoacetic acid gave the corresponding 4-pyranones (4 a or 4 b).

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Availability of Methylene Blue as a photosensitizer in photodynamic therapy was investigated, and it was found that the HeLa cells incorporated with Methylene Blue was strongly damaged by the irradiation with laser light. Methylene Blue was effective for the irradiation of longer wavelength, which has the large tissue penetration depth. The possible reaction mechanism of the cell damage via photo-produced singlet oxygen is discussed.

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The pore structure and mechanical strength of filler-loaded papers were studied for a wide range of filler contents. The handsheets with filler contents of 6% to 90% were prepared by mixing fossil sea-shell with softwood pulp. The tensile strength and the folding endurance were measured by a Schopper-type and the bursting strength by a Mullen machine. The pore structure of these sheets was measured by a scanning electron microscope and a mercury penetration porosimeter. The pore diameter of fiber sheet (filler content 0%) was mostly 20100 pm. The pore of 2-10 pm in diameter increased abruptly in the sheet with 14% filler content and further increased with an increasing filler content. When the filler content was more than 14%, the pore smaller than 2 pm increased. The pore with diameter of 2-.40 pm decreased in the sheets with 71%, and 90% filler content as compared with the sheets with lower filler contents. The filler particles looks like condensing at the network portions of pulp fibers and making their bonding weak. So, the mechanical strength was remarkably reduced even for the sheets with the lowest filler content. The filler content affected most significantly the folding endurance among three types of mechanical strength. By these experiments, the effect of filler content on the pore structure and the mechanical strength was clarified for highly filler-loaded papers. Key words: Filler-loaded paper, Filler content, Pore structure, Mechanical strength, Fossil sea-shell

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Newly synthesized azomethine-zinc complexes were examined as an emitting material in organic electroluminescence (EL) cells. Metal complexes which sublime in vacuum can be used for organic EL cells. Only inner complex salts were found to satisfy this condition. The inner complex salts of the azomethine-zinc complex were prepared by the reaction of zinc ion and ligands such as N-salicylidenealkylamine or N, N' -disalicylidenealkanediamine. A cell structure of [ITO/hole transport layer/emitting layer/MgIn] was employed. The EL cell with (N, N'-disalicylidene-1, 6-hexanediaminato)zinc(H) as an emitting layer showed a bright blue emission with an intensity of 1460 cdim2 for the first time as a complex emitting material. The emission peak was 462 nm.

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1', 3', 3'-Trimethy1-6-nitrospiro[2 H-1-benzopyran-2, 2'-indolines] (SPs) having methoxyl groups on the indoline ring were prepared and their photochromic properties were investigated not only in organic solvents but also in films. SPs showed "normal" photochromism in a less polar solvent, while "reverse" photochromism came to be observed as the solvent polarity was increased, and SPs having more methoxyl groups tended to show reverse phochromism in less polar solvent. Linear relationship between electronic transition energy (E_MC) of colored species and log was observed, where was the rate constant for coloration or decoloration. In micellar solution, λ max underwent significant blue shift and no linear relationship between EMC and In was observed, indicating the factors other than polarity are also operat ing on the isomerization processes. In film of poly(methyl methacrylate) or polyion complexes of poly(styrensulfonate)-distearyl dimethyl ammonium, normal photochromism was observed, but the rate of decoloration was considerably smaller than that observed for the decoloration in organic solvent of similar polarity, indicating the decoloration process was controlled not only by polarity but also by viscocity of the environment.

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Well-formed crystals of ZnWO4 were grown in Na20-W03 (Na20WO3 or Na202 W03) flux. Crystal growth was conducted by heating mixtures at 1100 °C for 5 h, followed by cooling to 500 °C at a rate of 5 °C/h. Grown crystals were colorless and transparent. The crystals had the forms of rod, thin plate, and thick plate. The rod crystals grown in Na20WO3 solution containing 50 mol% solute were up to 12 mm in length. Regardless of crystal form, the grown crystals were bounded by {100}, {010}, {110}, {102}, and {111} faces. In certain instances, the {111} faces did not appear.

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The modified dimethylaluminum reagents such as tris(dimethylaluminum)aryloxide (3), dimethylaluminum 4-bromo-2, 6-di-t-butylphenoxide (7), dimethylaluminum 2, 6-di-t-buty14-methylphenoxide (8), and dimethylaluminum 4-bromo-2, 6-diphenylphenoxide (9) can be utilized as mild Lewis acidic catalysts for the selective rearrangement of epoxides to carbonyl compounds under mild conditions. Among these, the catalyst 3 is highly effective for epoxy silyl ether substrates, while 9 is useful for simple epoxides.

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A dipivaroylmethane (Hdpm) chelate of strontium(II), Sr(dpm)2, was synthesized by the reaction of strontium metal with Hdpm in anhydrous benzene under a highly pure argon atmosphere and characterized by means of ICP, elemental analyses, FT-IR, 1I-I-NMR, "CNMR, and TG-DTA. The product was proved to be sufficiently pure so as to be used as a good source of MOCVD for the preparation of SrTiO3 thin films.

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A significant promoting effect of iridium was observed on vapor phase hydroformylation of ethene over Co/Si02 catalyst. The performance of catalyst depends on the precursors of cobalt and iridium. More than 70% of the selectivity of oxygenates was achieved on Co(A)-Ir(C0)/SiO₂ derived from Co(OCOCH₃)₂⋅4H₂O, and Ir₄(CO)₁₂ under the condition s of 4.1 MPa of a gas mixture of Ar/C2H4fCO/H2=10/30/54/6 at 423 K. Hydroformylation is considered to proceed on a highly dispersed cobalt metal. Iridium promoted the reduction of Co" on Co/SiO2 to cobalt metal by a hydrogen spillover mechanism.

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