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In order to validate the availability of rbNDVI (red and blue Normalized Difference Vegetation Index) for chlorophyll estimation, we conducted estimation of leaf chlorophyll concentration at heading to anthesis stage which highly correlates with grain protein concentration using ground-based and aerial hyperspectral data at agriculture fields in Gifu prefecture. In the ground measurement, rbNDVI showed high correlation (γ2=0.731) with leaf chlorophyll concentration compared to widely used NDVI (Normalized Difference Vegetation Index; γ2=0.231) and TCARI/OSAVI (Transformed Chlorophyll Absorption in Reflectance Index/Optimized Soil-Adjusted Vegetation Index; γ2=0.333), and the estimate equation is able to applied in the different study site (Root Mean Square Error: RMSE=2.54μg cm-2) . In the aerial scale, rbNDVI also showed good result in chlorophyll estimation (2006: γ2=0.427, 2007: γ2=0.447, RMSE=4.18μg cm-2) using atmospheric correction of 6S code and reflectance matching method. According to these results, the spatial distribution map of chlorophyll concentration was created. The spatial distribution map of chlorophyll concentration using rbNDVI may provide the useful information for additional fertilization aim to the improvement of the grain protein concentration over the large area.

Abrasive properties of cocoon shaped silica particles fabricated by a sol–gel method have been studied. Since silicon wafers are polished with slurry by the mechanism of Chemical Mechanical Polishing, polishing rates may depend on various chemical and mechanical factors, such as particle concentration in slurry, slurry pH and kinds of basic compounds for controlling the slurry pH.

Photosensitive organic-titania hybrid materials have been prepared from metal alkoxides and various organic ester compounds with \(C{=}C\) double bonds. The refractive index of the film increases with the decrease of the concentration of the organic ester compound, and the highest refractive index of 1.62 is obtained when 2-hydroxymethyl acrylate (HOA) is used as the organic ester and the molar ratio of HOA to Ti is 0.5. The material with the highest refractive index is exposed to femtosecond pulse using the multi-beam laser interference technique. After laser irradiation, the irradiated parts of the material are photopolymerized and periodic structures can be obtained by development of the unirradiated parts. In the case of laser irradiation of 120 μ J total energy for 5 min, the periodic structure obtained corresponds to 2D photonic crystal structure which is composed of two parts; the material with the highest refractive index and the air.

In order to produce an excellent abrasive, a fabrication method for cocoon shaped silica particles has been studied. The particles are prepared from TMOS, water, ammonia and methanol by a sol–gel method. The method is to add the methanol solution of TMOS at a constant supply rate to a mixture of water, ammonia and methanol. Effects of various reaction conditions such as temperatures, supply rates of TMOS, and amounts of TMOS are studied on the diameter and shape of the particles. The diameter and shape are resulted in depending strongly on temperatures. High temperature makes particles with the high aspect ratio and the small diameter. And the mechanism of forming the cocoon shaped particle is also discussed. It is concluded that the primary particles are generated at the beginning stage of reaction and two of them become the cocoon shaped particle. For the polishing efficiency, particles have high polishing efficiency with the diameter between 40 nm and 210 nm. As a result, best diameter of particles for abrasive is 40–100 nm with respect to polishing efficiency and surface finish.

Hybrid titania gel films are prepared from titanium butoxide and vinylpyrrolidone (VP). When the gel film is exposed to UV light, the CC double bond of VP in the film polymerizes and the solubility of the irradiated film decreases in HCl aqueous solution. The difference of the solubility between the irradiated and unirradiated parts makes fine patterning on the hybrid titania film whose refractive index is in the range between 1.8 and 2.1.

Fiber-optic carbon dioxide sensors with a dip-coated sol–gel film containing indicator dye of thymol blue are prepared and characterized. The sensitive film has both organic and inorganic parts with good gas permeability. The difference between attenuations in N 2 gas and in CO 2 /N 2 mixture gas increases with the increase in the CO 2 concentration in the 0.55–0.7 μm range. The attenuation difference increases linearly with the increase in the logalism of CO 2 concentration, although there is no difference under 0.1% CO 2 gas concentration. The sensitivity of the sensor increases with the increase in the dye concentration. The relative humidity and the film composition have an important effect on the attenuation difference.

Photosensitive hybrid titania films have been prepared from titanium butoxide modified with β-diketone and methacrylic acid. When this film is exposed to UV light, the β-diketonato chelate from the alkoxide and β-diketone is dissociated, and the unsaturated hydrocarbon of methacrylic acid is polymerized. These structural changes in the gel film have led to a difference between the solubility of irradiated and unirradiated parts in the film; therefore, a fine patternable hybrid titania film has been fabricated.

We report on a fabrication of photonic crystal structures in organic-inorganic hybrid films by a laser interference technique. Films containing the methacrylic group, which is photopolymerable by an adequate laser light, are prepared using a sol-gel technique from a mixture of organosilicate alkoxide and zirconium alkoxide modified by methacrylic acid. For the photopolymerization, the coated films on glass substrate are exposed to the interference light which is arranged with a square lattice in about 1 μm spacing. From microscopic images of microstructures produced by the photopolymerization, the influence of changes in conditions such as pre-bake temperature, photoinitiator and irradiation energy (laser power and duration time) on periodic structure is investigated. Adjusting the conditions, 2D and 3D photonic crystal structures with the micrometer-order period are formed in organo-silicate-zirconate hybrid materials.

A new fiber-optic ammonia sensor utilizing rectangular-cladding eccentric-core fiber and a sensitive film containing an indicator dye is demonstrated. The sensitive film is a SiO2-GeO2 gel film including an indicator dye of bromocresol purple or bromocresol green, which is dip-coated by a sol-gel technique. The attenuation of this sensor changes depending on the concentration of ammonia at the wavelength range of 500–700 nm. This sensor can detect several ppm of gaseous ammonia. Various factors determining the sensitivity to detect the ammonia gas and time response of the sensor are also studied.

The ZnII phosphate complex, [ZnII(bnp)(tpa)](ClO4) (2) was structurally characterized. The hydrolysis reaction of phosphate ester in 2 was promoted under acidic aqueous media efficiently. The relevancy of this system to P1 nuclease, which has a low optimal pH condition, is also discussed.

The influence of electrode materials on the current vs. voltage characteristics of limiting-current-type zirconia cells has been investigated systematically. The cells have one or two pairs of electrodes consisting of Pt, Pd, Au, or Ag, and a cover with a pinhole, which serves to limit gas diffusion and, therefore, the electrical current of the cells. The limiting current was found to depend definitely on the catalytic activity of the electrodes for the oxidation reaction of hydrocarbon gases in oxygen and hydrocarbon--containing gases. The results were applied to improve the sensitivity of limiting-current hydrocarbon sensors. The highest sensitivity was attained for the following combination of electrodes: Pt and Ag inner electrodes and a Au outer electrode in two-inner-electrode sensors. A preliminary examination has also been made on a three-inner-electrode sensor.

A method for synthesizing pyromellitic acid by liquid phase air oxidation of durene was studied. The air oxidation of durene was carried out in glacial acetic acid, using Co(OAc)2•4H2O, Mn(OAc)2•4H2O and KBr as catalysts, at the reaction temperature of 205-210°C and the total pressure of 20kg/cm2•G. The solid materials obtained by the oxidation were recrystallized into pyromellitic acid in an aqueous solution of nitric acid. The following results were obtained.(1) Cobalt and manganese used as catalysts were found, after oxidation, as salts in the solid material and had to be removed by treating with mineral acid to obtain pyromellitic acid.(2) The oxidation of durene into pyromellitic acid required a far larger amount of catalysts than the oxidation of p-xylene into terephthalic acid.(3) In the presence of heavy metal component, bromine component in the catalysts accelerated the latter stage of the oxidation, thereby promoting the formation of pyromellitic acid.(4) Bromine component in the catalysts suppressed the deactivation of heavy metal caused by the oxidation product.(5) Pyromellitic acid was produced from durene with the maximum yield of about 90mol%.

The hydrolysis reaction of 4, 5-bischloromethyl-m-xylene in alkali solution has been studied. The reaction was accelerated by emulsifing the raw material in alkali solution with surface active agent. The yield of 4, 6-bismethylol-m-xylene was about 90mol%, higher about 20mol%, than that obtained without surface active agent. It was found that the reaction-accelerating effect varied with the kind of surface active agent used, the agents of anionic series being more effective than those of nonionic series.Other factors responsible for the reaction were also examined in connection with reaction temperature, concentration of raw materials and alkali, etc.The hydrolysis of chloromethylpseudocumene was made by the same method with the result that its reaction mechanism was somewhat different from that of 4, 6-bischloromethyl-m-xylene.