It is known that liquid crystalline molecules can exist with guest molecules in the liquid crystalline state. If the structure of guest molecule is greatly different from that of the host molecule, a small amount of guest molecule disturbs liquid crystalline structure and inhibits the formation of the liquid crystal in the system. Therefore, the formation of liquid crystal can be controlled by structural change of the guest molecules. In this study, the photoisomerization of azobenzene moiety was utilized for this structural change. Here, polymer having azobenzene moiety as a side chain was synthesized by esterification of OH groups of polymer. The liquid crystal formation was examined in the mixture of the polymer containing azobenzene moiety (photo-sensitive polymer) and a liquid crystalline compound of low molecular weight by DSC and polarizing optical microscope. Temperature range of liquid crystal formation of this mixture decreased linearly with the increase of the concentration of azobenzene moiety in the system as observed in the mixture of p-methoxyazobenzene and a liquid crystal forming compound. It was confirmed that the liquid crystal formation is controlled by photoisomerization of azobenzene (trans to cis structural change). The masked image recorded by irradiation of 365 nm light is much stabler in the liquid crystalline mixture of photo-sensitive polymer than that in of p-methoxyazobenzene.

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One is a subsequent impregnation of alumina with an aqueous solution containing Ce ions and then with that containing Rh ions. The other method is a mixing of CeO₂/Al₂O₈ with Rh/Al₂O₂ so that the Rh: CeO₂ ratio is same as the ratio in the impregnated catalyst. The intimate contacts between rhodium and cerium oxide particles are much more expected in the former catalyst. In ord er to estimate the Oxygen Storage Capacity (OSC) values the catalysts were completely oxidized by injection of oxygen pulses, followed by cyclic pulses of oxygen and hydrogen until the consumptions of both gases on the catalyst were constant. The OSC of cerium oxide in the Rh/CeO₂/Al₂O₃ catalyst was found to be greater than that of the physically mixed catalyst, indicating that the intimate contacts between rhodium and cerium oxide particles dispersed on alumina play an important role for the OSC of cerium oxide in the catalyst. Because of these intimate contacts, hydrogen and oxygen activated on the surface of rhodium particles are easy to spill over the neighboured cerium oxide particles to react with lattice oxygens and oxygen vacancies in the ceria crystallites. Thus, the intimate contacts between rhodium and cerium oxide particles are essential for the enhanced OSC of cerium oxide.

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Recently we have found that ZSM-5 type zeolites containing calcium show the excellent catalyst performance for methanol conversion to light olefins at high temperatures above 500°C and that the crystal size is controlled by adding boric acid. s The catalyst life of the microcrystalline aluminoborosilicate containing calcium synthesized in the presence of boric acid increased with a decrease in the crystal size. In this paper, in order to extend further the catalyst life, the zeolites were mechanically mixed with various alkaline earth metal carbonates. The methanol conversion was carried out over the CaCO₃-mixed aluminoborosilicates containing calcium with various crystal sizes (Fig.1). The catalyst life increased with a decrease in the crytal size of the zeolite used. In the case of the microcrystalline zeolite with crystal size of 0.3 μm, the catalyst lifetime with higher yield than 50% for C₂H₄ and C₈H₆, was extended extreamly to about 130 h. Effects of the amount of alkaline earth metal carbonates on the catalyst life and the initial product distribution were also studied (Table 2, Fig.2). It was found that among the alkaline earth metal carbonates, the mechanical mixing of the microcrystalline zeolite with SrCO₃ in a weight ratio of 2: 1 was effective for elongation of the catalyst life. The yields of C₂H₄ and BTX decreased with an increase in a weight ratio of SrCO₈/zeolite. On the other hand, the yield of C₈H₁₀ increased with the weight ratio. These results seem to be attributed to the change of acidity of the zeolites. The steam stability of CaCO₈- or SrCO₈-mixed microcrystalline zeolite was also investigated by means of ²⁷A1-MASNMR. It was found that the mixing of SrCO8 has a little effect on the resistance to steaming of microcrystalline zeolite. The long-term catalyst life test of the SrCO₈-mixed microcrystalline zeolite was carried out by using dimethyl ether instead of methanol (Fig.4). The time with higher yield than 60% for C₂H₄ and C₈H₆ was about 2600 h.

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Praseodymium oxides doped with small amounts of platinum and palladium (Pt/PrOx, Pd/PrOx) have been examined as a reforming catalyst for moderate temperature fuel cell systems. The catalysts were prepared by a wet process. The activity and the selectivity for the catalytic decomposition of methanol to hydrogen and carbon monoxide (H₂+CO) were studied in a flow reactor at a temperature range of 250-700°C. The activity of the catalysts increased with increasing the amount of the doped metals. The catalyst with 0.5% Pt, Pt/prOx (0.5%), had as a high activity as that of Pt/Al₂O₃ (0.5%), a commercial Pt catalyst supported on alumina. The reaction selectivity to H₂+CO on Pt/PrO₅ was much superior to that on Pt/Al₂O₃. Pd/PrOx showed both a high activity and a high selectivity at the reaction temperature below 400°C. For the reaction at a high temperature range above 500°C, the catalytic activity was reduced by the deposition of by-product carbon on the catalyst. The results of temperature-programed desorption (TPD) and mass spectrometries showed that the Pt/PrOx and Pd/PrOx catalysts scarecely form dimethyl ether and lead the high selectiv ity for the H₂, and CO formation.

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A lead(II) zirconium titanium trioxide (PZT) was prepared by a spray pyrolysis of a nitrate solution, and the influence of evaporation of PbO during the process of the formation of PZT was investigated. The yield of PZT decreased with an increase in the temperature of spray pyrolysis. For comparison, a barium zirconium titanium trioxide (BZT) was prepared by the spray pyrolysis of a nitrate solution. Contrary to the case of PZT, the yield of BZT increased with an increase in the temperature of spray pyrolysis. The se results indicate that the application of the spray pyrolysis to the preparation of PZT is not appropriate, because PbO evaporates from the particles during the pyrolysis.
Although the spray pyrolysis products consisted of PZT and other phases, the compositions of the products were almost the same as the feed solutions. When the product was fired at 1100°C, a nearly single phase of PZT was formed. The PZT synthesized by the spray pyrolysis, however, had a larger compositional fluctuation than that synthesized by a solid-solid reaction among PbO, ZrO₂ and TiO₂. The maximal dielectric constant near the Curie temperature of the sample decreased with an increase in the temperature of spray pyrolysis. PZT was also prepared by another method, viz., a combination of a spray pyrolysis and a solid-solid reaction. PZT synthesized by this method had no compositional fluctuation.

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An amperometric sensor for monitoring aqueous dissolved chlorine in a strong acidic electrolyte containing reducible Bi³⁺ was developed. Cyclic voltammograms of a porous carb on electrode coated with RuO₂ were measured in strong acidic electrolytes containing no molecular chlorine with and without Bi³⁺. The applicable potential to measure the reduction current of dissolved molecular chlorine without the interference by Bi" was determined to be ca. O.50 -ca.0.80 V vs. Ag/AgCl/3.3 mol. dm^-3KC1. When a potential in the region was applied to the developed sensor, into which the sample electrolytes including molecular chlorine were flowed, the detected current was proportional to the concentration of dissolved chlorine at a constant temperature irrespectively of the presence of Bi³⁺. Plotting natural logarithm of current against the reciprocal of temperature gave a straight line with the slope of ca.4.3 kcal.mol^-1, which corresponds to the activation energy on diffusion of dissolved molecular chlorine. The obtained value for a dissolved chlorine concentration coincided with the theoretical one. Concerning the measurement of the concentration of dissolved chl orine in a strong acidic electrolyte in a larger zinc-chlorine secondary battery system for electric power storage, the utilization of the sensor was tested in a real scale. Research and Development on a Dissolved Chlorine Sensor. I.

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A rapid and simple detection method for anionic surfactants is proposed.A 200-μl portion of test solution adjusted at pH 4-6 is dropped onto the filter paper impregnated with equimolar mixture of zinc and aluminum hydroxides. After being dried, the paper is moistened with water. Dodecylbenzenesulfonate (DBS) is detected as a white spot. The identification limit is 1 μg. When a drop of ethanol and a drop of Rhodamin B solution adjusted at pH 5.5 are added to the white spot, a reddish violet spot is obtained. The identification limit for DBS is 0.2 μg. For the spectrophotometric determination, the reddish violet spot is washed with water to remove excessive Rhodamine B and extracted with ethanol. The absorbance of the extract is measured at 545 nm. DBS ranging from 5 to 100 ppm can be determined. Cationic, nonionic and amphoteric surfactants do not interfer with the determination of anionic surfactants,

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Mono-, di- and tri-bridged ferrocenophanes containing an azatetramethylene bridge have been synthesized. Treatment of 6-oxo[ 3 ]ferrocenophanes with hydroxylamine gave the corresponding ketone oximes, 6-oxo[ 3 ] (1, 1')-, 6-oxo[ 3 ] (1, 1')[4] (2, 2')-.6-oxo-[3](1, 1')[4] (3, 2')-, 6-oxo[3] (1, 1')[4] (3, 3')- and 6-oxof 3 1 (1, 1') [4 (2, 2')4] (4, 4')ferrocenophane oximes. The E- and Z-isomers of the compounds were separated by colum n chromatography, and their stereoisomeric structures were determined by ¹³C-NMR spectrometry. The (E)- and (Z)-oximes were converted into amides having a nitrogen atom at 6- and 7-positions of the bridge, respectively, by Beckmann rearrangement with PC1₅. R eduction of these amides with LiAlH₄ afforded the corresponding azaferrocenophanes bridged with a 6- or 7-azatetramethylene chain. The amines were very sensitive to air and acids, and 7-amines were more unstable than 6-amines. In the electronic spectra of 6-amines the d-d absorption band (415-430 nm) of ferrocene nucleus shifted to the short wavelength with increase of the number of the bridges, but those of 7-amines showed an irregular shift behavior with variation in the number and the position of the bridges.

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Miike coal was hydrogenated under reaction conditions of 400°C for 30, 60, 90 and 120 min, and the resulting samples of asphaltene were used in this study (As-1--4). The four asphaltene were subjected to GCP to separate them according to molecular weight (As-1-4-1--7, 9). The asphaltene GPC fractions were subjected to elementary analyses, measurement of molecular weight and ¹H-MNR. Subsequently, the structure was analysed according to two procedures: the Brown-Ladner method for average structural units and the Williams method for average molecular structure.
Asphaltene GPC fractions showed fairly good separation; molecular weight diminished from 3500 to 300 with increasing GPC elution volume. From the results of structural analyses, asphaltene molecules consist of quite small structural units regardless of the wide distribution of molecular weight, corresponding to 2 to 5 aromatic ring systems with alkyl groups bearing 2 to 3.5 carbons and functional groups substituted onto half of their peripheral aromatic ring sites. In view of the above findings about the structure of average molecules and structural units, asphaltenes appear to be constituted of oligomers and polymer high molecules with polymerization degree, Np, from 2 to 8 binding structural units of the type described above.
Proceeding the depolymerization of asphaltene during hydrogenolyses reaction, hydrogenation of aromatic rings and 4iydrocracking of alkyl group in structural units occured to bring a gradual shift to smaller unit structure. In the 'final reaction step, monomer structures corresponding to unit structures are produced as oil by degradation of oligomer asphaltene.863

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Inulo-oligosaccharides( I ) production, by use of immobilized p-fructofuranosidase from Aspergillus Oryzae was investigated. Chito-pearl-BCW-4010 was the best carrier for immobilization of the enzyme. ' The optimum temperature was 25°C and the optimum pH was 6.8 for production of ( I ) from sucrose and fructose. When the molar fraction of sucrose was increased for sake of forming of enzyme-fructose complex, sucrose acted as an acceptor sugar to form fructooligosaccharides. This dose not contribute to formation of ( I ). A disubtituted sucrose derivative retaining (Fruf 2 β--α 1 Glcp) bond reacted with immobilized enzyme to form the complex. This complex reacted with fructose to form the disubtituted inulobiose which was converted to inulobiose in good yield.

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The kinetic mechanism of the cholesteric-phase formation from the nematic state was investigated by polarizing microscopy and polarized light scattering. The concentrated solution of Poly(γ-benzyl L-glutamate) (Mv=1.5 x 10⁵) in N, N-dimethylformamide at a volume fraction of 0.191 (v/v) was prepared in a glass tube (thickness=2, 0 mm) sealed to prevent solvent evaporation. This sample was held at nematic temperature of 90°C for 5 days andsuddenly cooled to 20°C. Microscopic pictures and light scattering patterns were taken at successive time intervals. The qualitative interpretation of the light scattering patterns was performed by reference to the results on the study of the distortion of an ordered structure in the suspension of ionic polymer latex particles by Ise et al..
It was found from the results of these experiments that the formation of the cholesteric structure from nematic state occurred in three steps as follows: ( 1 ) At first the uniform nematic domain was divided into some polydomains (Fig.1), in which the cholesteric pitch was not observed; ( 2 ) Irregular cholesteric pitch appeared in each domain under a polarizing microscope and the pitch became more regular at successive times (Fig.2). The average value of the pitch did not change with time (Fig.5) but only its standard deviation gradually diminished and reached at a constant value (Figs.3 and 4). The direction of the cholesteric axis normal to the retardation line does not, on the whole, oriented at this step; ( 3 ) During successive long time further change occurred in the cholesteric structure. Some cholesteric domains assembled together and became progressively greater in size. On the other hand, cholesteric axis was oriented along equatorial direction as depicted by arrow in Fig.6-1. Thus macroscopically homogeneous structure of the cholesteric phase was formed in equillibrium state. Liquid Crystalline Structures of Poly-a-amino Acids. VI.

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2-s-Butyl-4, 6-dinitrophenol (BDNP) was chemically modified ?t o p olymerizable amphiphile, [10-(2-s-butyl-4, 6-dinitropherioxycarbonyl)decyl] [2-(methacryloyloxy)ethyl]dimethyla mmonium bromide via 2-s-butyl-4, 6-dinitrophenyl 11-bromoundecanoate 1.2 was converted to a, oligomer 3 with ca.6500 of molecular weight by a radical polymerization. Krafft point of 2 was found to be 32.3°C. CMC values of 2 and 3 were found to be 2.7 x10^-4 and 4.0 x10^-4molfi, respectively by the measurements of conductivity of their aqueous solution.1, 2, and 3 exhibit antibacterial activity against Staphylococcus.

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Approach for identifying the soot obtained by combustion of benzene, toluene, o-, m-, p-xylene, ethylbeinzene, styrene and cumene was carried out by means of curie point pyrolysis gas chromatographic method. The soot was collected outside the diffusion flame. The pyrolysis temperature was changed from 170°C to 764°C. Biphenyl in the benzene soot ana xvlene in the xylene soot were useful specific components for identification of the soot. Pe ak ratio of benzene and toluene was also available for identification of the soots. As the result of examination both on the peak ratio of these specific components to others, and on peak ratio of benzene to toluene in the pyrogram, the most suitable pyrolysis temperature for ii-lAntiratinn of soot was determined to be 590°C. t Studies on Identification of Soot. II.

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The formation process of perovskite-type oxide was investigated by following the thermal decomposition behavior of double complex, [Co(NH₃)₆] [La(CO₃)₃].H₂O, in the range of room temperature to, 1000°C. The decomposition product at 400°C was amorphous and contained CO₃^2- ions. Cubic perovskite-type oxide, LaCoO8, was found to form at 600°C, though CO₃^2- ions still remained. The formation of oxide with cubic structure was almost co mplete at 750°C. Specific surface area of oxide calcined at this temperature was (6.5±0.3) m². g^-I. Further heating to 900°C gave the rhombohedral oxide. Specific surface areas of oxide calcined at 900 and 1000°C were (6.3±0.3) and (5.7±0.5) m2. g^-1, respectively.

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Keto-enol tautomeric equilibriums of diethyl oxalacetate 1, dimethyl oxalacetate 2, diethyl α-chlorooxalacetate 3 and dimethyl α-chlorooxalacetate 4 were determined by ¹H-NMR spectroscopy. Enol tautomers, which were stabilized by intramolecular H-bonding to give six-membered ring, existed in almost E coofigiiration. In 1 and 2 enolic forms existed richly i n chloroform, and the tautomeric equilibrium of 1 was not altered with changing the temperature or using benzene as solvent. While keto tautomers were superior to enol in α-chlorooxalacetates, by reason that they had only one proton which 'can be enolized and that the enolic forms were unstabilized by cross conjugation with +M effect of the chlorine atom.

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The container materials suitable for determination of dibutyltin (DBT) and tributyltin (TBT) compounds in seawater have been studied. Three commercial container materials of glass, polyethylene and polycarbonate bottles were used. One bottle of each material was filled with a stock solution dissolving dibutyltin dichloride (DBTC) and tributyltin chloride (TBTC) in seawater, and the concentrations of DBTC and TBTC were analyzed periodically by gas chromatography with flame photometric detection (GC-FPD). It was found that polyethylene bottle was not suitable for use as seawater container because of adsorption of TBTC on the surface of container, but the glass and polycarbonate bottles were suitable. Studies on the Determination of Trace Amounts of Organotin Compounds in Seawater and the Behavior of their Compounds in Marine Environment. V.

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The purpose of the present study was to conduct a basic work of the tr ace analysis of phospholipids in biological urine and serum samples. Phospholipids were extracted with chloroform using Extrelut column and developed by TLC. Solutions of PL-C and Al-P were sprayed on the TLC plate (silica gel), and released phosphate was detected with molybdate-Malachite Green solution. This method can be easily used for the separation and determination of phospholipid content as low as pmol.

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