An outgassing rate was measured for a stainless steel material of YUS130S, having a high-mangany content (Fe-18Cr-7Ni-11Mn-0.3N), and compared with that for a stainless steel of SUS304L. A surface processing of both electropolished and electrochemical buffing followed by an in-air oxidation was examined in order to investigate the outgas reduction effect in the case of with and without baking. Further, a depth profile of the surface composition was analyzed by glow-discharge emission spectroscopy (GDS). Based on the results, the outgassing rate of YUS130S was 35% lower than that of SUS304L, when electropolished and electrochemical buffing. The oxidation process in air at 723 K in the case of electrochemical buffing showed effect on the outgassing reduction in both YUS130S and SUS304L. The GDS observation shows that, by electropolishing, Cr-Mn-rich and Cr-rich passive films were formed on the YUS130S and SUS304L surface, respectively. By electrochemical buffing, passive films changed to more Fe-rich films. The further process of in-air-oxidation causes a change in oxide films to Fe-Mn-rich and Fe-rich characteristics for YUS130S and SUS304L respectively. The stainless steel with Mn-rich and Cr-poor passive films shows low outgassing rate.

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  We have investigated thermal stability and adsorption structure of trans-beta-hydromuconic acid (HOOC-CH2-CH=CH-CH2-COOH) on Cu(110) surface as a function of sample temperature using Temperature Programmed Desorption (TPD), Low Energy Electron Diffraction (LEED) and Fourier Transform Infrared Absorption Spectroscopy (IRAS). From 350 to 500 K, hydromuconic acid adsorbed as monohydromuconiate (HOOC-CH2-CH=CH-CH2-COO^-) form, corresponding to the structure of c(2×2). As the temperature increases to about 600 K, monohydromuconiate changes to bihydromuconiate (^-OOC-CH2-CH=CH-CH2-COO^-) corresponding to the structure of p(1×2) or p(6×2). Bihydromuconiate structure decomposed at around 600 K.

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  Approximately 250-nm-thick Ga-doped zinc oxide (GZO: 3 wt.% Ga₂O₃) films have been prepared on glass substrates at room temperature by pulsed laser deposition (PLD) using ArF excimer laser. During the deposition process, oxygen with partial pressure of 0-1.0 Pa was introduced in the chamber. The film fabrication was carried out under condition of laser energy density with 0.6 to 2 J/cm². The lowest resistivity of 3.34×10^-4 Ω•cm was obtained under optimized condition of laser energy density of 1 J/cm² with oxygen partial pressure of 1.0 Pa. For the GZO films fabricated with laser energy density of 1 and 2 J/cm², the values of surface roughness Ra obtained by AFM observation were 2.93 and 3.14 nm, respectively.

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  Vanadylphthalocyanine (VOPc) thin films, grown with epitaxy and quasi-epitaxy, were prepared using organic beam epitaxy equipment on KCl and KBr substrates. The VOPc thin film fabricated on KBr substrate changes from a VOPc thin film dominated by epitaxy to one mainly grown with quasi-epitaxy, with the increase in annealing time. On the other hand, the VOPc thin film prepared on KCl substrate transferred from VOPc thin film mainly grown with epitaxy to quasi-epitaxy with the increase in annealing time. We also observed the surface morphologies of VOPc thin films fabricated on KBr and KCl substrates by using Atomic Force Microscopy (AFM) with the increase in annealing time. On the KBr substrate, abundant nano-size VOPc crystals were observed on the VOPc thin film, based on the increase in annealing time. On the KCl substrate, the VOPc thin film grows with the depositing process; dominated by the step-terrace of the KCl substrate surface.

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  Ion fragmentation of methylsilane by a hot tungsten wire in a Freeman-type ion source was investigated with low-energy mass separated ion beam apparatus for the study of catalytic chemical vapor deposition (Cat-CVD) processes. The mass analysis showed that dominant fragment ions were typically H₁⁺, H₂⁺, H₃⁺, CH₃⁺, SiH⁺, and SiCH₄⁺. The ion production rates, which depended strongly on the tungsten wire temperature, decreased with time due to modification of the tungsten wire surface during the process. The x-ray diffraction and x-ray photoelectron spectroscopic measurements showed that silicon carbide, carbon, and tungsten carbide compounds were formed on the tungsten wire surface during the process.

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  Thermal diffusion of implanted Ag atoms in 25-nm-SiO₂/Si and nanoparticle formation after annealing at various temperatures were investigated by a high-resolution RBS and cross-sectional TEM. Ag atoms were implanted into the thermal grown thin oxide layer on silicon substrate by negative-ion implantation at 10 keV with 5×10¹⁵ ions/cm². The samples were then thermally annealed at 500, 700 and 800°C for 1 h. In the HRBS measurement with 400 keV He⁺ beam, Ag atoms in the as-implanted sample were found to have almost the same depth profile as a predicted one by TRIM-DYN calculation, although some Ag atoms diffused to the surface due to local heating during implantation. After annealing at 500°C, a main fraction of Ag atoms appeared at a depth of 12 nm as same as that of the as-implanted sample, and two small precipitations of Ag atoms appeared at depths of 7 and 22 nm. After annealing at 700°, the only one fraction peak of Ag atoms appeared at a depth of 20 nm with a relatively narrow FWHM. At this temperature, the XTEM observation revealed the Ag precipitation at 700°C was contributed from the mono-layered Ag nanoparticles. The both of small and remarkable precipitations of Ag atoms observed at a depth around 22 nm just near the SiO₂/Si interface after annealing at the temperature less than 700°C, suggested the existence of a diffusion barrier against Ag atoms in the thermally grown SiO₂ on Si. This is considered to be due to compressive stress in the transition layer in SiO₂ just near the crystalline Si surface. However, after annealing at 800°C, the Ag atoms diffused to the SiO₂/Si interface at 25 nm.

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  Analytical chemistry in the perspective of ab initio molecular orbital calculation is introduced by investigating the chemical reaction between transition metals Cr and Fe with sodium diethyldithiocarbamate (NaDDC), a complexing agent to detect and extract Cr in human blood sample. Using density functional theory—based calculations, we determine the stable structure of the Cr-DDC and Fe-DDC complexes and obtain its dissociation energies. We found dissociation energy values of -3.24 and -2.67 eV for Cr and Fe complexes, respectively; and hence the formation of the former complex is more favorable than the formation of the latter.

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