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Kinetics of interchange between boric acid and tetrahydroxyborate has been studied by the band shape analysis of nB NMR signals in aqueous solution of pH 8-10 at 20-52 °C and 0.1-250 MPa. The system was analyzed as two-site exchange B(OH)3 -B(OH)4-The observed first-order rate constant toward the right (kx) is related to the second-order exchange rate constant (kex) by the equation kx = fccxCi[OH-] /(Zcb + [OH-]), where kh = [B(OH)3]-[OH"]/[B(OH)4-], and Cj is the total concentration of boron. Under the given conditions kex is (2-7) X 106 dm* 123 mol-1 s-1 and AH*, AS*, and AV* are 20.1 ± 1.0 kJ moH, -55.0 ± 3.1 J mol"1 K"1, and -9.9 ± 0.5 cm3 mol"1, respectively. The activation parameters reflect the transition state forming dimeric [( )3 (µ-) ( )3]-.

SynopsisUsing a steam oxidation testing apparatus, operating under almost the same steam conditions as those in actual boilers, the influences of temperature and pressure (especially above critical pressure) on steam oxidation were investigated with austenitic heat-resisting steels such as SUS 347-HTB, 17-14CuMo, and the newly-developed 20Cr-25Ni and 22Cr-35Ni steels for advanced fossil steam plants.Oxidation loss in weight increased with higher steam pressure and temperature. Increase of Cr and Ni contents improved the oxidation resistance. Cr concentration in inner scale increased with Cr content of steel. This caused the higher resistance to steam oxidation. The existence of a Ni enriched layer at the scale and metal interface contributed to the improvement of steam oxidation resistance. The Ni concentration of the layer was higher in steels containing a higher Ni content.Morphological investigation of the scale cross sections showed that considerably large amounts of voids and cavities were produced in the outer scale of SUS 347HTB and 17-14CuMo steels oxidized in steam at high temperature and pressure.

Preliminary questionnaire ( enquete ) examination how effectively the facial images could be used for gender and age estimations was executed by using 300 different faces and 21 examinees. Wrinkles appeared in the face and the shape and size of the facial parts are selected to model the age and gender estimation in this research basing on this enquete. Image processing algorithm for wrinkle modeling was proposed iz this paper. In addition, a method for making relationships between faces and their keywords was proposed by using the latent semantic indexing. An efficient inteiface for displaying the relationships among keywords and facial images has been introduced with 2D/3D-feature space defined by the indexing.

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