The aim of this study is the in situ monitoring of phase change under emulsion preparation process by using QCM method. Water in oil type (W/O) emulsion was prepared by mixing water phase (sodium chloride aqueous solution), oil phase (mixture oil, liquid paraffin: kerosene =9:1) and emulsifier (sorbitan sesquioleate, monoester: diester =1:1) at a rotating speed of 800 rpm. Oil in water type (O/W)emulsion was prepared from water phase (distilled water), oil phase (liquid paraffin) and emulsifier (tetraoleic acid poly (oxyethylene) sorbitol). The platinum coated crystal and the propeller of a mixer were immersed in oil or water and emulsifier, and water or oil was dropped in above liquid with burette. The resonant frequency was monitored by frequency counter. In the case of W/O type emulsion, at first resonant frequency increased, but after that it decreased below the initial value until the end of water phase dropping. After the end of water phase dropping, the resonant frequency decreased. In the case of O/W type emulsion, at first resonant frequency increased until the end of oil phase dropping and after that it slightly decreased. In general, resonant frequency decreased by the increase of density and viscosity of liquid that contact with QCM electrode. Consequently, in this study, resonant frequency was dominated by the change of density and viscosity. Hence, this method could be an effective tool for monitoring the preparation process of emulsion.

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An ionic gel microactuator was prepared and its performance was studied under a low voltage range from 100 to 500 mV, and a periodic repetition of swelling and shrinking in the gel on the microactuator was confirmed clearly. A rapid response of the gel against a voltage change was confirmed by an observation of swelling and shrinking of the gel under an alternating voltage of T= 0.4 s. It continued a periodic swelling-shrinking repetition longer than 5 hours, although the amplitude of the periodic motion reduced gradually, due to the evaporation of water from the gel. Moreover, deposition of electroconductive materials between two microelectrode causes an electric short circuit and fatal damage of the microactuator. So, it is necessary to prevent the evaporation of water and the deposition of electroconductive materials for the stable operation of the microactuator.

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Dehydrogenation of ethylene glycol (EG) to glycolaldehyde (GA) was carried out using a fixed-bed flow reactor. High selectivity for GA was obtained when the Cu-Zn catalyst (1:1) calcined at 1000 K was used. During the reaction the catalytic activity prominently decreased within 100 h. However, an introduction of small amount of oxygen ( (1-5)× 10^-2 molar amount of EG) resulted in a steady conversion of EG with the high selectivity over 100 h. The steady formation of GA over 600 h was accomplished by the immobilization of the Cu-Zn catalyst onto a-alumina. A powder X-ray diffraction analysis and a differential thermal analysis revealed that the catalyst in an activated state includes an oxidized copper.

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The bis (sulfophenyl) phosphonate-formaldehyde resin was prepared by the reaction of diphenyl phosphonate-formaldehyde resin with fuming sulfuric acid. The acid dissociation exponent of this resin was about 5. This resin had the hygroscopic property, and could be used as the adsorbent of water in organic solvents. The adsorption capacities of water in acetone and acetonitrile were 1.4 and 2.0 mmol/gR, respectively. The resin had the thermally stable polymer, and its weight loss on thermogravimetry were 2.0 wt% at 100 °C, and 7.5 wt% at 150 °C, respectively.
By use of the resin as acid catalyst for esterificat ion, the yield of the esters formed with saturated primary alcohols (C₁-C₄) and saturated fatty acids (C₂-C₇) were about 70-90% yield at 25°C. The esters of saturated secondary alcohols (C₃-C₉) with acetic acid were obtained with 81-89% yield at 100°C. When the resin was used for esterification several times, the depression in catalytic activity was very small.

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Polyester (PET) fabrics were treated with meso-1, 2, 3, 4-tetrabromobutane (TBB) at 130°C in water for various periods, in order to promote flame retardancy. Scanning electron microscopy and energy dispersive X-ray spectroscopy showed that TBB diffused into PET fibers. The amount of sorbed TBB reached a maximum in 15 min and decreased after that. It was necessary to decrease the contact time between TBB and water at high temperatures, in order to maintain the amount of sorbed TBB. The flame retardancy of treated PET fabrics was evaluated by the limiting oxygen index (LOI) method. The LOI value was directly proportional to the amount of sorbed TBB. PET fabrics were treated in water-TBB dispersion systems, in order to decrease the contact time between TBB and water. As a result, the efficiency of sorption reached ca.60% when the amount of added TBB increased to 10% o. w. f. In the case where the liquor ratio was reduced, the efficiency increased. It reached 82.4% when the treatment was carried out with 5 % o. w. f. TBB at liquor ratio of 1: 5. It is presumed that molten TBB came into contact with PET fibers, TBB molecules adsorbed on the surfaces of PET fibers and diffused into PET fibers. It is concluded that TBB is favorable for treating PET fabrics efficiently, because the sorp tion mechanism of TBB is different from that of other bromine-containing flame retardants which have high melting temperatures.

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Precipitation pH was automatically measured on site for each 0.5 mm-rainfall sample at 29 nationwide stations in Japan in Phase-II of Acid Deposition Survey from 1989 FY to 1992 FY by Japan Environment Agency. The mean pH of all of the stations over the entire survey period was pH 4.6. There was no pH record less than pH 3.0 which was supposed to affect plant growth. In western Japan and in remote islands in the Sea of Japan, lower pH was observed than in the other regions. Regarding seasonal variations, pH was rather lower in winter and spring. The mean pH of initial 0.5 mm-rainfall was lower than that of the whole rainfall at many stations, although it was higher at 8 stations. The monthly means of pH based on the automatic measurements of 0.5 mm-rainfall samples were compared with those from the manual measurements of biweekly samples, showing that the automatically determined pH was lower than the manually determined one by 0.3 pH unit on average. One of the possible causes of this pH difference is solution of alkali particles in the stored samples.

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Hydrocarbon (HC) poisoning for Pd catalysts has been investigated. Adsorbed species on deteriorated Pd catalysts were analyzed by various methods such as GC-MS, FT-IR, XPS etc. The relations of the oxidation states of Pd, Al and Ce of Pd/Al₂O₃ and Pd/CeO₂ with the HC chemisorption were examined. It was concluded that the cause of deterioration of Pd/Al₂O₃ was due to the decrease of the number of active sites by HC chemisorption, and that the cause of deterioration of Pd/CeO₂CeO₂ was due to the decrease of O₂ storage capacity by HC chemisorption. Particularly, the mechanism of the decrease of O₂storage capacity was that HC became to adsorb on the position the oxygen vacancies of CeO₂. It was clarified that the performance of deteriorated Pd catalysts was regenerated by heat treatment at 500°Cfor 1 hour in the air.

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The ruthenium (III) complexes of diisobutyrylmethane (H-DIBM) and isobutyrylpivaloylmethane (H-IBPM) gave an excellent suitability as precursors for metalorganic chemical vapor deposition (MOCVD). DIBM and IBPM complexes exhibited faster vaporization rate than the conventionalruthenium(III) complex of dipivaloylmethane (H-DPM) at the same temperature. Since vaporization in the liquid state is possible because of low melting point, the deposition rate of ruthenium oxide gives constant stability. Two materials are excellent precursors to prepare thin films by MOCVD.

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The reactive extraction of Cephalosporin C ester directly from the fermentation broth of Cephalosporin C was studied in Liquid-Liquid two phase system using ethyl acetate.
When the volumetric fraction rate of ethyl acetate phase was 0.33 or more, the effect of agitation was not observed on the reaction rate. On the other hand, the effectiveness of agitation appeared at the ratio 0.17 or less. It was clarified that the rate determining step of this reactive extraction was mass transfer to reaction interface by a series of experimental results.
An excellent correlation was also obtained betwe en the scale-up factor (Z), showing power consumption ratio of agitation, and the over all mass transfer coeffcient at the volumetric fraction ratio of 0.17.

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Analytical conditions were optimized for derivative synchronous fluorescence spectrometry by using fluorene, carbazole and anthracene as examples. For the precise determination of these compounds, it is necessary to obtain reproducible synchronous fluorescence spectra. First-, second-, third- and fourth- ?derivative spectra were measured on the basis of the original spectra. The determination with a relative standard deviation (RSD) of approximately 1.0% can be achieved by measuring the intensities at appropriate wavelengths in such derivative spectra. The characteristic peak of the original synchronous spectrum will be observed as a valley and a peak in the 2nd- and 4th-derivative spectra, r espectively. Therefore, the derivative intensities at the valley and peak wavelengths were most favor able for the measurements. In the 1st- and 3rd-derivative spectra, on the other hand, the difference in intensity a t a particular peak and valley was suitable for the reproducible determination. The peak and valley to be used, in such case, must be chosen at both sides of the zero-crossing where the wavelength corresponds to that of the original characteristic peak.

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