In the field of cosmetics, it is very important to investigate catalytic activities of pigments, which may degrade the quality of products, such as foundations, lipsticks, and blushers. Inactivation of the pigments is indispensable in the preparation of high quality cosmetics. We have developed a novel method for producing functional pigments in a two-ste p method ( 1 ) chemical vapor deposition (CVD) of 2, 4, 6, 8-tetramethylcyclotetrasiloxane (H4), and ( 2 ) hydrosililation. After the H-4/CVD process, it was found that the H-4 molecules deposited on pigments formed a network structure of polymethylsiloxane (PMS), which seems to have been caused by catalytic activities of the pigments, as shown by the following 226 * IL A 1993 No.3reaction; 2 Si-H+ H2O Si-O-Si + H2The thickness of PMS film on the pigment surface w as estimated to be less than 1 nm, which corresponds to a mono- or bimolecular layer. In spite of their small thickness, the catalytic activity of PMS-pigments was totally eliminated. In the second step, various functional groups coluld be added to the PMS film by the following reaction; Si-H C H2, CHR SiCH2CH2R (R: functional group)Introduction of several different functional groups was attempte d. For instance, when alkyl groups are added by the above reaction, the surface of pigments are not only deactivated but also altered to be hydrophobic. These hydrophobic pigments, which disperse easily in oils and waxes, made it possible to generate brighter, vivider, and glossier colors in certain cosmetic Koducts. Also, n oteworthy is the fact that we have produced novel columns for high-performance liquid chromatography (HPLC), using spherical silica particles treated by the H-4/CVD process. The polymer-coated packings showed a high chemical stability, even in alkaline mobile phases. They have similar separation characteristics to those of conventional silylated silica packings. Polymercoated C18 packings, prepared from high-purity silica also showed an excellent preformance in the analysis of protonated amines and chelating compounds, which are normally considered difficult to analyze due to their undesirable secondary interaction with the silica surface.

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The J-aggregates of 3, 3'-bis(sulfopropy1)-5, 5'-dichloro-9-ethyl-thiacarbocyanine were formed on the surface of octahedral and cubic AgBr microcrystals in photographic emulsions. Dye positive holes in the aggregate, which were generated under illumination, gave rise to an electron spin resonance (ESR) signal. The signal intensity increased and became to be saturated with increaseing the power of microwave. The power of microwave required for the saturation became stronger by increasing the quanity of the dye, and was stronger for J-aggregates on octahedral AgBr microcrystals than for those on cubic ones. By taking into account that the aggregate size increased with increasing the quantity of the dye and that the positive holes could escape from the aggregates to the cubic microcrystals more rapidly than to the octahedral ones, it was considered that the restriction of the saturation was due to the incessant migration of positive holes in the aggregates which enhanced spin-lattice relaxation.

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Copper manganites, Cu1Mn304, with a cubic spinel structure were prepared by thermal decomposition in a range of 1.0≤x≤1.5, and their cathode properties in a lithium battery were investigated. Our attention was directed to their high electrical conductivity. The cubic spinel was obtained as a single phase for x=1.2 and 1.4, whereas it was mixedw ith a tetragonal phase for x=1.0 and with CuO for x=1.5. They had a d. c. resistivity of 30, --55cm at room temperature which decreased with an increasing copper content up to x= 1.4. The open circuit voltage (0. C. V. ) was found to decrease slowly with lithium content (y in Li, CusMn304) up to y=0.7 for x=1.2 and to y=0.85 for x=1.4, respectively. Thereafter, 0. C. V. decreased more rapidly. As rhe discharge proceeded, their lattice slightly expanded and became distorted, suggesting that lithium was intercalated electrochemically into the cubic spinel copper manganites. Moreover, after deep discharge (y>0.3), the concentration of copper near the cathode surface increased and metallic copper deposition was observed. Below y=0.3, the lithium intercalation seemed to proceed incorporated with the reduction of Mn4+ to Mn" according to high 0. C. V. values (2-2.5 V). For 0.3 Cy<z (z=0.7 for x=1.2, z=0.85 for x=1.4), intercalated lithium was considered to push Cu out of the host lattice onto the surface, where metallic copper formed.

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The membrane reactors using three kinds of ionic conductors have been constructed in order to control the oxidative dehydrogenation of ethane electrochemically (Fig.1). SrCe0.95Ybo.0 53-a, Yttria-stabilized zirconia (YSZ) and BaCeo.9Y-O0.1-3-a were employed as protonic, oxide ionic and their mixed ionic conductors, respectively. When ethane and air were introduced at 700 °C into the anode and the cathode, respectively, and the direct current was passed through the reactor, the formation rate of ethylene became larger as the current density increased in all the reactors (Fig.4). From the measurement of the anodic potential, one can speculate that the activation of ethane is based on the decrease in partial pressure of hydrogen in the pore of the anode (Fig.5). The current efficiency for the formation of ethylene decreased in the order of SrCeo.95Yb0.0, 03_, BaCe0.9Y0.103_. and YSZ (Table 1). This order can be explained by the thermal energy generated by changing the entropy of proton in the anodic reaction (Fig.6). On the other hand, the formation rate of carbon dioxide increased with increasing the basicity of ionic conductors (Table 1).

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The adsorption characteristics of various gas molecules such as N2, H20, CO2 and NH3on magadiite, kenyaite and their polysilicic acids have been studied. The specific surface areas calculated from isotherms of N 2 at 196 °C were 23 m2/g for magadiite and 32 m2/g for kenyaite, which indicated that N2 molecules were not adsorbed into the interlayer space of these silicates. However, adsorption into interlayers was observed for layered polysilicic acids obtained by eliminating alkali ions from the polysilicates. The specific surface areas increased to 32 m2/g for H-magadiite and 105 m2/g for Fl-kenyaite. Adsorption isotherms of H20 at 25 °C showed a rapid increase in step at a relative pressure of about 0.05 for magadiite and kenyaite. This confirmed the “intermediate phase” in the hydration/dehydration process of magadiite and kenyaite. Much more CO2 was adsorbed at 25 ° C on ken yaite and H-kenyaite than on magadiite and H-magadiite. The adsorption site for CO, may be attributed to an 8-membered ring of these layer compounds. By using CH, and C2H6 as probe molecules instead of CO, , the effective size of these rings was estimated to be less that 3.2A_ for the magadiite-type structure and 3.5A. for the kenyaite-type structure. The interlayered surface acidity of all compounds was measured by stoichiometric tiration with NH3.

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In volcano and hot spring areas, alteration of rocks under acidic conditions have been observed as the result of leaching rock forming components. The alteration of rocks under strong acidic conditions was reproduced by the laboratory experiments and the leaching process of components, i. e. Na, K, Ca, Mg, Fe, Al and Si from the rock was investigated. The experiments were done in the flow system and the sample solutions were collected continuously in several fractions. In order to compare the efficiency of the leaching process for the 7 components under the same conditions, differential leaching index of each component was defined in each fraction as follows. S = wt. of X component in the solution after reaction total wt. of 7 components in wt. of X com p onent R the rock before reaction total wt. of 7 components Differential leaching index of X component in every fraction=S/R The indexes of Na, Ca and Al were high in comparison with the other 4 components indicating that these 3 components were leached out more quickly. The index of Si had a maximum value at some point of time and the tendency to be lower than those of the 6components. As the time went on, Na, Ca, and Al were leached out quickly, followed by K, Mg and Fe. As the result of all the components except Si being leached out, the residual rock became relatively enriched in Si02.

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The effect of carbon black on flameless atomic absorption spectrometry of aluminum fluoride and phosphate has been previously reported. This report deals with the dire ct atomization of titanium(II), OD and (IV) oxides which formed fireproof compounds, and the differential determination of each other oxides utilizing carbon black effects on flameless atomic absorption spectrometry. Titanium(II), 010 and (IV) oxide samples were ground to fine powder (about 2.0 um in partic le size) with a grinder. Test solutions were prepared by dispersing the sample powder and carbon black in distilled water, using an ultrasonic agitator. Ten 121 of the dispersion solution was taken in a graphite furnace and atomized directly. The maximum enhancement in sensitivi ty was found for titanium(Y) in presence of carbon black of 0.5 w/v%. In contrast, the sensitivity was decreased for the dispersed solutions of titaniumOD and (11) oxides. The differential determination of a mixture of two titanium oxides was investigated, making use of the difference in the effect of carbon black.

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Conventional liquid-junction potentials are examined by pH measurements in glass electrodereference electrode cells with salt bridges of mixed electrolytes and recommended compositions of the salt bridges are proposed for pH measurements based on JIS. Salt bridges used consist of the first electrolyte (KC1, CsCl, or KNO3) having cationic and anionic transference numbers of nearly 0.5 and the second electrolyte (acetate or haloacetate) for regulation of the transference numbers. Apparent response slopes of the glass electrode determined with two pH-standards (phthalate and neutral phosphate) increased with the addition of the second electrolyte. Differences in the conventional liquid-junction potentials (4E (convent. ))in the two pH-standards were expressed by a function of the mole fraction (x2) of the second electrolyte at constant ionic strength; dEl (convent, )= B x2I (x2+ C) where A is a constant depending on the nature of the first electrolyte, B on the combination of the first and the second electrolytes and C mainly on the nature of the second electrolyte. The above equation was derived semiquantitatively from the Henderson equation and the transference numbers in the mixed electrolyte. Salt bridges of 3.903 moldm-3 KC1-0.09, mol. dm-3CH3CO2K, 2.41 moldm-3 KNO3-0.59 m oldm-3 KC1, and 1.13 m ol dm-3 KNO3-1.87 moldm-3KC1 are recommended for measurements in pH-regions covered by pH-standard g roups of oxalate phthalate neutral phosphate, phthalate neutral phosphate borate, and neutral phosphate borate carbonate, respectively, because straight calibration lines were obtained for each group of the three standards within an experimental error, though the response slopes were lower_than the Nernstian one.

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The statistical design of experiments was applied to the preparation of activated carbon from thiolignin with alkali. The most effective factor on specific surface area, iodine adsorptivity and yield of the produced carbon was proved to be the weight ratio of alkali (activating agent) to thiolignin. The optimum alkali ratio was confirmed to be 2 for NaOH and 3 for KOH, respectively. The pre-heating of thiolignin at 200 °C gave activated carbon with large surface area under the same conditions. The other facfors giving the maximum of specific surface area (3084 m2 g-') were shown to be carbonization temperature of 550 °C, carbonization time of 3 h, rate of temperature rise of 1 °C and quantity of added water of 40 ml to 50 g of raw materials. Activated carbon of satisfactorily higher specific surface area (more than 3000 m2 g -1)could be obtained also from the black liquor concentrate washed out the mineral components with water, under the conditions of carbonization temperature of 600 °C, carbonization time of 3 h and rate of temperature rise of 1 °C

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Oxidizing abilities of the COD(Cr) method using IC2Cr207 and the COD(Mn) method using K, MnO, for organic compounds have been examined and compared using benzoic acid, L-glutamic acid, tartaric acid and chloride ion. The Std. COD (Cr) ([H]=18 M) method conforming to the JIS (Japanese Industrial Standards) gave the highest oxidation efficiency (0. E. hereafter) to benzoic acid. In contrast, the Mod. COD(Cr) ([H+]=2.4 M) sho wed the weakest. To obtain the same O. E. as Mod. COD(Mn) ([1-1+]=2.4 M), the COD(Cr)method required the [1-11-] of 9-10 M. At the acid concentration higher than ca.15 M ([H+]), the COD(Cr) method gave strong 0. E. The 0. E. of the COD(Mn) method becam e stronger as the [1-1+] increased (untill ca.2.5 M), but decreased rapidly after that (ex.0%at ca. [H+]-, --6 M in the case of chloride ion). The effect of temperature for the COD(Cr)method was clear-cut the higher the temperature, the higher the O. E., although the Std. COD(Mn) method gave no clear temperature dependence. The heating time effect was also clear for the COD(Cr) methods, i. e., the longer the time, the higher the O. E. However, the COD(Mn)methods gave characteristic decomposition curves with maximum values in the region of 30-60 min. O. E. for both COD methods was studied from the point of view of redox-potential. Calculated apparent formal potentials explained the difference in O. E. of both COD methods lEers" ([H]=18 M) =1, 34 V, EM Std ([H+] =1 M) =1.27 V; Ec, "d([H+]=2.4 M) =1.18 V, {Emni" ([H]=2.4 M) =1.31 V}. Experimetal potentials were measured at 25° C and 50 °C, and these experimental potentials also showed relatively good agreemen t with the O. E. of both COD(Cr) and COD(Mn) methods (Fig.6).

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Molecular weight distribution of humic substance extracted from grass peat was proved to be ca.1500 by gel filtration chromatography. Dissolved substances in ground water were separated into three fractions, and the molecular weights of them were ca.1000(I), 300-400(II) and less than 20000, containing with polysaccharides and inorganic salts. Activated carbon from thiolignin carbonized at 450 °C with NaOH, developing in micro pores of more than 10 nm in diameter, could effectively adsorb the component appeared at E260 from grass peat extract. Humic, substance fraction I from ground water, little more hydrolyzed than humic substance from peat, adsorbed by activated carbon with micro pore of more than 5 nm in diameter. The fraction II, showed the highest trihalomethane-forming ability, was shown to be removed effectively by activated carbon with micro pore of diameter ranging 2-5 nm.

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Tetramethylammonium hydroxide (TMAH) (1) solution which was free from chloride ion was synthesized by electrolyzing its formate (6) in an electrolytic cell with a cation exchange membrane, and this salt 6 was synthesized from trimethylamine (2) and methyl formate ( 5 ). Thus, 6 was prepared with a 3000 ml stainless autoclave by dissolving 470 g (8 mol) of 2 and 720 g (12 mol) of 5 in 800 g of methanol and keeping the mixture at 131 °C for 10 h. Its yield was 79.2%. If higher temperature was used in this synthesis, the decomposition of 5 is accelerated, forming a large volume of CO gas, which makes the operation of the reaction dangerous. Next, 268 g (2.25 mol) of 6 was electrolyzed by impressing 20 V for 15 h and 610 g of 30.1% TMAH solution was obtained. Since HCOOH was not perfectly electrolyzed to CO 2gas in the condition of the present study, a small amount of the acid migrated into the catholyte (TMAH solution). Its concentration was about 17 ppm when the concentration of the catholyte was about 16% TMAH. All contaminents of metallic ions were less than 10 ppb, respectively.

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Electrically conductive composite of polypyrrole/polyurethane foam was prepared by exposing polyurethane foam containing ironaln chloride to pyrrole vapor. The conductivity of the composite foam was 10-5-10-2 Scm-i. The conductivity depended on content of iron(111)chloride in polyurethane foam, polymerization time and atmosphere of polymerization. The stability of composite foam in air was estimated by measuring the change in conductivity. Highly stable foam was obtained by washing the foam with acetone after polymerization of pyrrole. The thermal properties of the composite foam were investigated by DSC and TG, and it was found that the composite foam had thermal stability comparable to untreated polyurethane foam.

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Solubility of potassium chloride (KC1) in poly(ethylene oxide) (PEO) oligomer showed a negative temperature dependence. The solubility of KC1 in PEO, with a molecular weight (Mw) of 200, was 0.7 mol// at 57 °C, but it was reduced to 0.2 mol/l at 148 °C. The cry stal of KC1 formed in the PEO oligomer was microscopically analyzed to be cubic crystal system which was the same as that recrystallized from an aqueous solution. The negative temperature dependence of the KC1 solubility was also observed in other PEO oligomers (M, =300and 400). The solubility of KC1 decreased with increasing molecular weight of the PEO. This is ascribable to a decrease in the relative content of the terminal hydroxyl groups.

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Amorphous porous silica was prepared from silicic acid and dicarboxylic acid dichlorides. Silicic acid was treated with malonyl dichloride, succinyl dichloride, adipoyl dichloride and sebacoyl dichloride in tetrahydrofuran (THF) at room temperature, and resulting powd ers were calcined at 450, 600 and 800 °C for 3 h in the furnace under 0 atomsphere. The specific surface area of amorphous porous silica thus obtained could be controlled between 960 and 149 m2/g at 600 °C by chosing the starting dicarboxylic acid dichloride and calcination temperature.

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