The preparation of fine powders by grinding may be accomplished by either a wet or a dry process andthe differences between these have been discussed. The difference of breaking strength in differentatmospheres affects the grindabilities. In this study, bending tests were carried out using a drop weightmethod on glass material in order to investigate the quantitative effect of water atmosphere on strength. Theinfluence of the crack length of the glass surface on the difference of fracture probability in water and in airwas also studied. As a result, it was found that the fracture probability in water was larger than that in airwhen the input energy in specimen was constant. Then, the difference of the fracture energy in water and inair increased with decreasing the crack length.

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We examined NIR spectra obtained from various plastic wastes using a portable near infrared spectrometer;herein, we discuss chemical implications of spectral characteristics. A barcode spectrum derivedfrom the second-order derivatives spectrum provides effective alternatives to discriminate plastic types. Principal component analysis, which is applied to barcode spectra, reveals characteristics and similarity of NIR spectra among plastic samples. Chemical structure of plastic samples reflects NIR spectra. Spectral differencescan be explained with reference to whether the plastic has some functional group (aromatic CH, COand Cl) or not.

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A new porous carbon material has been developed utilizing a natural porous structure of rice bran. Theoriginal porous carbon material (rice bran carbon, RBC) are manufactured by mixing the defatted rice branwith a phenol resin, pressure forming, drying, and then carbonizing at 900°C. Therefore, the RBC has aporous structure. In this study, the authors investigated new manufacturing processes to strengthen the RBC. As a preliminary, the RB carbon particles are manufactured impregnating a phenol resin (25wt.%) with thedefatted rice bran and carbonizing at 900°C. In the first strengthening process, the mixture of the carbonized RB carbon particles and a phenol resin are then pressure formed to make a disk-shape RB carbon (CRB) Since the RB carbon particles are brittle and therefore they are broken during the pressure forming, the poresize can be smaller in the CRB than in the RBC. In the second strengthening process, the mixture is in jectionmolded to make a rectangular RB carbon (IMCRB). The pore size is also smaller in the IMCRB. Thecompressive strength, bending strength and fracture toughness are increased in the both strengthened materials.

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It is well known that p-tert-butylthiacalixarenes can make host-guest complexation with organic guestmolecules and metal cations. In order to study crystal structural properties of the titled host molecule withorganic compounds, we tried to make a new crystal of the p-tert-butylthiacalix [6] arene. Fortunately, twonew crystal structures of p-tert-butylthiacalix [6] arenes complexed with toluene and with benzyl alcoholwere obtained. The conformation of the complex with toluene is the cone conformation; on the other hand, the conformation of the complex with benzyl alcohol is 1, 2, 3-alternate.

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Ba (Ta_1-xZr_x)O_εN_δ compounds for x=0-1 were produced by carbothermal reduction and nitridationprocess. In this process, Ba (Ta_1-xZr_x)O_εN_δ and TaC as a second phase were observed by X-ray powderdiffraction patterns. Work functions and barium vaporization temperatures of the obtained powders wereestimated. Work functions of the Ba(Ta_1-xZr_x)O_εN_δ compounds increased with increasing zirconium content, and the value of 1.7eV for x=0.1 was less than that of 2eV with alkaline earth oxide. Barium in the Ba (Ta_1-xZr_x)O_εN_δ compound was volatile at higher temperature than that of authentic hot cathodes coatedwith alkaline earth oxide. In the 4.1mm of outside diameter, 3.3mm of inside diameter, and 100mm length of glasses with 9.3kPa of argon gas and mercury, some fluorescent lamps with hot cathodes coated with Ba (Ta_0.8Zr_0.2)O_2.2N_0.6 compound worked excellently and those has been lit for 61.2Ms, so far.

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