Flexible hosts, regioselectively hetero-labeled 6^A-anthranilate-6^X-O-p-tosyl-labeled β-cyclodextrins (X=B or G, C or F, and D or E for β-1, β-2, and β-3, respectively), have been synthesized to investigatetheir chemo-sensor potential as host compounds for biochemical substances such as bile acids and terpenoidsas guest molecules. These hosts showed pure monomer fluorescence, exhibiting increase in fluorescence intensityon complexation of the all guests examined. The extent of the fluorescence variation with a guest wasemployed to evaluate the sensing abilities of these hosts, and the sensing parameter (ΔI/I⁰) was used to describethe sensing abilities of the hosts. Hosts β-2 and β-3 recognized bile acids with high sensitivity, whereas β-1 detected all guests examined with low sensitivity. On the whole, the sequence of the bindingability of these hosts was β-3>β-2>β-1 for bile acids. The behaviors of the appended units of these hostsduring a formation of the host-guest complexation were studied by induced circular dichroism (ICD) andfluorescence spectra. The ICD spectra of these hosts showed same patterns. The guest-induced variations in ICD and fluorescence spectra suggest that anthranilate and tosyl units take movement with a changing theirmutual relationship in the place to work as spacers. The parameter values of the titled hosts are much higherthan those of homo-labeled anthranilate β-cyclodextrin analogs.

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Pyrometallurgical process is utilized to recover zinc in the form of high purity zinc oxide from a kindof zinc metal scrap containing 92.49 wt% zinc. The process uses tube-type furnace, where the reactor isdivided into volatilization zone and oxidization zone by flowing nitrogen gas and air. In the process, zinc isfirstly volatilized to vapor in inert atmosphere of nitrogen gas and carried forward to oxidization zone bynitrogen gas, then oxidized to zinc oxide in air atmosphere. The effect of temperature, air and nitrogen gasflow-rates, and reaction time on both purity and yield of the product is investigated in detail in this study.Subsequently, the characteristics of the products are examined by X-ray diffractometer and scanning electronmicroscope. The obtained results demonstrated that both the purity and the yield of the product haverelationships with the operation parameters. The contents of the impurities grow with the rise of temperature, with the increase of nitrogen gas or air flow-rate, and also with the extension of reaction time. However, theyield decreases with the decrease of temperature, with the reduce of nitrogen gas flow-rate, with the rise ofair flow-rate, and also with the diminishment of reaction time. In addition, very low air flow-rate resultedin the increase of metallic zinc in the product and the decrease of the yield of the product at the same time.Zinc oxide with purity of 99.97wt% and yield of 94.45% in nano-grade dimension can be obtained inpresence of 300 ml/min N₂ flow-rate and 800 ml/min air flow-rate for 12 minutes at 1253 K, whereas theimpurity content of Al, Fe, Cu, Pb and Cd is 0.0072wt%, 0.00060 wt%, 0.00096wt%, 0.0048wt% and 0.00031wt%, respectively, which approaches the quality demands of the first-grade-zinc oxide in JIS (Japanese Industrial Standard) K 1410-1995.

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A field experiment for snowfall at the coastal area in northern Japan was performed, and chemical components in snow were analyzed. When the synoptic weather pattern is a high pressure in the west and a lowpressure in the east of Japan (WH & EL), it is influenced that the sea-salt concentration in the snow was inproportion to the squares of the wind speed at the sampling site. This relationship offers that the amount ofsea-salt aerosol supplied from sea surface to air mass and finally to the snow depends strongly on the squaresof the friction speed on the sea surface and of the wind speed at the snowfall site.

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Bridgman growth of tin crystal was carried out in a graphite crucible that was fixed on a quartz supportrod or a copper one. The growth rate and axial temperature distribution were examined by recording thetemperature variation with time at each of four prescribed positions in the solid-liquid system duringsolidification. 1) Actual growth rate of crystal increased with progress of solidification while the furnaceelevated at a constant rate, but the tendency was different depending on the type of support rod used. 2) We could increase the temperature gradient in the crystal-melt system without varying the interface shape, ifwe used a copper support rod in place of a quartz one together with raising the maximum temperature ofthe furnace. 3) The thermal conductivity of the crucible support rod is thought to be an important factoraffecting the growth rate and temperature gradient in the growth system in the Bridgman process.

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