Professor Ertl was awarded the chemistry Nobel Prize. One of his remarkable works is imaging of surface non-linear processes for CO oxidation on Pt(110). The mechanism for this pattern formation is briefly discussed. We studied previously laser-induced desorption (LID) from NO on Pt(111) extensively. However, the experimental results could not be explained until the adsorption structure of Pt(111)-NO was elucidated consistently in 2002 by the experimental and the theoretical investigation. For Pt(111)-CO at low coverage, on the other hand, the most stable adsorption structure obtained from the ab initio calculations is in contradiction to that confirmed by the experimental studies.

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  The adsorption structure of Pt(111) surface was studied by thermal desorption spectroscopy (TDS), infra-red absorption spectroscopy (IRAS), scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED). LEED dynamical analysis, with the aid of other techniques, concluded that NO occupies the fcc hollow site at a low coverage, the fcc hollow and ontop sites at a medium coverage and the fcc hollow, ontop and hcp hollow sites at a high coverage, which is consistent with the other experimental and theoretical results. The desorption temperatures of NO on the fcc hollow (α species), ontop (β species) and hcp hollow sites (γ species) are 390, 300 and 200 K, respectively. The N-O stretching vibrations of each species are 1430-1490 cm^-1, 1710 cm^-1 and 1508 cm^-1, respectively. Annealing to 250 K causes the desorption of the γ species, which results in the highly ordered two site occupied (α and β) surface. The high energy (>1 eV) electron injection from the STM tip causes the desorption of the β species, which enables us to get the surface of highly ordered α species. The mechanism of the desorption of the β species is the electron injection to the 2π_a orbital, which has an anti-bonding character for the Pt-N bonding of the β species.

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  The adsorption states and diffusion processes of NO molecules on Pt(997) at low coverage were investigated by using infrared reflection absorption spectroscopy (IRAS), scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. When NO molecules adsorb on the surface, each molecule transiently migrates on the surface from the first impact point to a possible adsorption site at low temperature (11 K). There are four stable adsorption sites for NO on Pt(997); the bridge site of the upper step, the fcc and hcp-hollow sites of the terrace, the on-top site of the terrace and the fcc-hollow site of the lower step. At higher temperature above 45 K, NO molecules start to diffuse thermally to more stable adsorption sites, and finally they are trapped at the bridge sites of the step which are the most stable adsorption sites among the four sites.

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  Adsorption and reaction of NO and CO on Ir(111) and Rh(111) were investigated by infrared reflection absorption spectroscopy (IRAS), and temperature programmed desorption (TPD). Two NO adsorption states, indicative of hollow and atop sites, were present on Ir(111). Only NO adsorbed on hollow sites dissociated to N_a and O_a. N_a desorbed as N₂ by recombination of N_a and by a disproportionation reaction between atop-NO and N_a. Preadsorbed CO inhibited atop-NO, whereas hollow-NO was not affected. Adsorbed CO reacted with O_a and desorbed as CO₂. NO adsorbed on the fcc-hollow, atop, and hcp-hollow sites in that order over Rh(111). The hcp-NO was inhibited by preadsorbed atop-CO, and fcc-NO and atop-NO were inhibited by CO preadsorbed on each type of the sites, indicating that NO and CO competitively adsorbed on Rh(111). From coadsorbed Rh(111) surface, N₂ was produced by fcc-NO dissociation, and CO₂ was formed by reaction of adsorbed CO with O_a from dissociated fcc-NO.

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  Rotational and vibrational energies of desorbing products in chemical reactions provide information on dynamical processes of bond formation and bond rupture and also on structures of transition states. Energies of product CO₂ in CO oxidation on metal surfaces can be determined by analysis of infrared chemiluminescence spectra from CO₂. However, angle-resolved (AR) measurements of these energies in thermal surface reactions have long been lacking due to difficulty of experiments, although AR measurements is required to obtain detailed structural information. In this review, recent progress in the AR measurements in CO oxidation on Pd surfaces is described. It was found that both internal and vibrational energies changed depending on polar- and azimuthal angles, surface structures, and rotational/vibrational modes. From these phenomena, new insights into transition states and energy partition dynamics can be obtained.

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  A new version of synchrotron-radiation-based x-ray spectroscopy, wave-length-dispersive near-edge x-ray absorption fine structure (dispersive-NEXAFS), and fast x-ray photoelectron spectroscopy have been applied to mechanistic studies on several surface catalytic reactions on platinum-group-metal surfaces. In this review, our approach using above techniques to understand the reaction mechanism and actual application studies on three well-known catalytic surface reactions, CO oxidation on Pt(111) and Pd(111), NO reduction on Rh(111) and H₂O formation on Pt(111), are introduced. Spectroscopic monitoring of the progress of the surface reactions enabled us to detect reaction intermediates and analyze the reaction kinetics quantitatively which provides information on reaction order, rate constant, pre-exponential factor, activation energy and etc. Such quantitative analyses combined with scanning tunneling microscopy and kinetic Monte Carlo simulations revealed significant contribution of the adsorbate configurations and their dynamic changes to the reaction mechanisms of the above fundamental catalytic surface reactions.

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  Corrosion wastes more than a few percent of the world's GDP every year. The initial stage of the corrosion is one of the central topics in material science. The oxidation is one of the major corrosion processes of metals. Thus, the study of the oxidation process on metal surfaces is generally interesting in various fields of science and technology. The growth of a protective thin surface layer, which prevents further oxidation into bulk of a metal, requires the formation of a homogeneous film. One simple way for the protection of underlying metals is surface alloying, combining different substances to form multi-component surfaces. The surface alloying leads to the formation of a protective oxide layer due to the preferential oxidation of one component, possibly with surface segregation. Copper and copper alloys have wide industrial applications, and therefore are of interest for studies of oxidation mechanism, especially in the Cu₂O formation. Cu forms the stable Cu₂O, while Au does not form a stable oxide and is not soluble into stable Cu₂O. Thus, the Cu-Au alloy system is ideal for investigating the effect of alloying on the formation of protective layer against further oxidation into bulk. Here, we introduce our recent comparative studies of the oxidation of Cu(100) and Cu₃Au(100) with hyperthermal O₂ molecular beam and discuss why Cu₃Au(100) is protective against the oxidation.

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  真空の科学と技術，大気の圧力の研究などのグエリケの業績は大変大きいにも関わらず，その全貌は不十分にしか紹介されていなかった．これは一つには彼が馬を用いて行ったマグデブルグの半球の実験があまりにも有名すぎたせいかもしれない．特にこの事情は我が国において著しいので，著者は 1. 叙説に続く 2. において現在得られる情報によりグエリケの伝記の概略を紹介することを試みた．さらに 3. において，彼の著作を中心に科学的業績について略説する．最後に 4. の結語において今後検討すべき課題について述べる．なお日本の文献は殆どが生まれたときの名前である Otto Gericke の姓であるゲーリケと書いてあるのに，本稿では“グエリケ”としたのは，現在欧米の文献は1666年の神聖ローマ帝国貴族の叙爵後の名前である Otto von Guericke を用いているから，それに従ったのである．

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  In dynamic diffusion pump systems, such as vacuum evaporators and sputter coating systems, where the chamber is frequently evacuated from atmospheric pressure to high vacuum, the oil-vapor backstreaming problem sometimes occurs owing to the excessive gas load flowing into the high-vacuum pump just after switching the evacuation mode from low-speed roughing to high-speed, high-vacuum pumping. Two kinds of excessive gas loads exist just after crossover: (1) gas molecules in the vacuum chamber space and (2) temporarily increased outgassing from the chamber wall surface. The outgassing rate from the chamber wall surface becomes very large with the rapid reduction of pressure owing to high-speed, high-vacuum pumping, because the time constant of diffusion of gas molecules in the wall surface is much larger compared with the time constants of pumping down and the resultant reduction of sorption rate of impinging gas molecules. Slow high-vacuum pumping, followed by high-speed pumping, is very effective to suppress the temporarily increased outgassing load and the adverse effect of the space gas load, and to meet the maximum throughput capacity of the diffusion pump. Providing with a low-conductance bypass valve makes it possible to use a small-volume buffer tank and a low-speed rotary pump as a backing pump, leading to a reduction in the cost of high-vacuum evacuation systems.

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  A Titanium Nitride (TiN) coating system for long beam ducts of accelerators was developed to reduce the secondary electron yield (SEY) from the inner surface and to mitigate the electron cloud effect. Coating was carried out by DC magnetron sputtering of pure titanium in argon (2.0 Pa) and nitrogen (0.5 Pa) atmospheres. A copper beam duct with a maximum length of 3.6 m was set vertically, and a titanium rod as a cathode was suspended from the top along the central axis of the duct. A movable solenoid coil with a length of 0.8 m externally supplied a magnetic field of 16 mT to accommodate the long duct. By moving the solenoid coil at specified time intervals, the TiN film was uniformly coated on the inner surface. The thickness of the coating was 200 nm, and the temperature of the ducts during the coating was 130°C. Several coated ducts were installed into the KEKB positron ring during the summer shutdown in 2007. In the subsequent beam operation, the reduction of electrons in the coated duct was confirmed.

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  A field emission apparatus operating at cryogenic temperatures was developed by using an Al-SUS explosion bonded metal composite to get a good thermal contact of the sample and the radiation shield with the liquid helium reservoir. With this apparatus, a tip sample temperature of 4.1 K was observed when the liquid helium reservoir was evacuated. As an electron detector, a micro channel plate (MCP) was set on the bottom of the liquid helium reservoir cooled at ~10 K. The performance of the MCP at low temperatures was examined by using ultra violet light as an input signal. It was confirmed that the MCP has a sufficient amplification at 11.9 K.

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  Yamaguchi university will open extension course “Basis and application of Vacuum Technology” in this year. The history, aim and specific features of this extension course are shown in this article.

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