A surface analysis study is presented to establish the effects of oiliness agents and extreme pressure agents added in the lubricants for steel sheet rolling. Rolling oils are used as coolant for rolls and as lubricant to reduce the friction between the roll and the strip. The degree of wear between them depends on the state of the film produced by absorption and surface reactions of the lubricant on the metal surfaces. Quantitative EPMA analysis proves that a phosphoric acid ester used as the extreme pressure agent decomposes into phosphoric acid which subsequently reacts with the steel surface to form a film of iron phosphate. The difference in the secondary P ion intensities detected by SIMS on the surface of low carbon steel sheets rolled with different amounts of the ester suggests the optimal amount of the esters to be added in the lubricant oil is in a range of 3 to 5%. Synthetic fatty acid esters, used as the oiliness agent, with a structure containing N atoms found to show a much better lubrication than the conventionally used compounds of a straight carbon-chain structure and non N atoms. This was also assured by the XPS analysis of rolled low carbon steel and SUS 304 steel sheets.
Medium energy ion scattering (MEIS, 100 keV) has become of interest in the field of the surface and the interface structural analysis of metals, semiconductors, metals on semiconductors and so on, because of its high depth resolution from the surface to the bulk. Also we can determine the atomic positions very precisely (± 0. 001 nm) from the channeling and blocking effects. The principles of ion scattering for the structure analysis some measuring equipments and experimental results are reviewed with a comparison of the high energy ion scattering (HEIS, MeV) and low energy ion scattering (ISS, keV).
This is part 1 of a series of lecture notes providing introductory exposition of statistical mechanical theories of adsorption processes. Both non-localized and localized adsorptions, without and with interactions among adsorbed molecules (atoms), are discussed at the level of elementary statistical mechanics.
The formation of calcium oxalate films on stainless steel from dilute aqueous solutions containing Ca2+ ions and dimethyl oxalate has been studied by measuring the precipitate rate of calcium oxalate in the solutions, and by the thermal analysis and the X-ray analysis of calcium oxalate in the films and of the precipitates in the solutions. It was found that the supersaturation of solutions was maintained during the film formation and the initiation of the film formation was not consistent with that of the precipitation of calcium oxalate. The solubility of calcium oxalate and the rate of the hydrolysis of dimethyl oxalate affected the degree of the supersaturation of calcium oxalate. The water content of crystallized calcium oxalate in the films was different from that of the precipitates in the solutions.
We have applied a scanning Auger electron microscope to measure secondary electron coefficients (δ) of the niobium plate used for the superconducting RF cavities in TRISTAN Main Ring. The secondary electron emission from the superconducting RF cavities plays a crucial role in determining the maximum accelerating fields. Surface morphology, exposure to the air, and surface treatments influence greatly on the electron emission from the niobium surfaces. In particular, ultrasonic rinsing in H2O2 after electropolishing and surface smoothing of the niobium plate to eliminate scratches has been shown to be very effective in suppressing the electron emission from the niobium surfaces.
An epitaxial growth mechanism of oxide superconductor films has been investigated by using computer graphics for the combination of orthorhombic Ba2YCu3O7-x with substrate crystals of SrTiO3, MgO, and ZrO2. The (001) plane of Ba2YCu3O7-x has been shown to fit well the (100) plane of these substrate crystals. A crystallographic fit has also been demonstrated between the (110) plane of Ba2YCu3O7-x and the (110) plane of SrTiO3. Detailed investigation of atomic arrangements has indicated some differences in the ionic interaction at the superconductor-substrate interface among SrTiO3, MgO, and ZrO2 substrates. For the combination of the (001) plane of Ba2YCu3O7-x and the (100) plane of SrTiO3, various layers of Ba2YCu3O7-x and SrTiO3 are possible to provide arrangements of ions which stabilize the electrostatic interaction at the interface. Although the Ba-O layer of Ba2YCu3O7-x does not provide such a stable interaction with the MgO (100) plane, the Cu-O layer of Ba2YCu3O7-x can favorably interact with the MgO (100) plane. As for ZrO2 (100) plane, ionic arrangements at the oxide layer is favorable only for the interaction with Y3+ layer of Ba2YCu3O7-x while the Zr-O layer of ZrO2 can interact with both Ba-O layer and Cu-O layer of Ba2YCu3O7-x.
Studies on the distribution of trace element in biological samples have been carried out to investigate physiological functions of these elements and to establish a method for monitoring environmental pollutions. Particle Induced X-ray Emission (PIXE) analysis is available for this purpose, since PIXE is sensitive enough to detect many trace elements simultaneously and without any separation processes using proton beam scanning even with a small sample. In this paper, we report spatial distributions of various trace elements in several human tissues and foods, and discuss their environmental significance.