Akira Kouchi

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The reactions of cold H atoms with solid O2 molecules were investigated at 10 K. The formation of H2O2 and H2O has been confirmed by in-situ infrared spectroscopy. We found that the reaction proceeds very efficiently and obtained the effective reaction rates. This is the first clear experimental evidence of the formation of water molecules under conditions(More)
A conceptual design was developed for a cosmo-biology experiment. It is intended to expose simulated interstellar ice materials deposited on dust grains to the space environment. The experimental system consists of a cryogenic system to keep solidified gas sample, and an optical device to select and amplify the ultraviolet part of the solar light for(More)
Deuterium (D) atoms in interstellar deuterated methanol might be distributed into complex organic molecules through molecular evolution by photochemical reactions in interstellar grains. In this study, we use a state-of-theart high-resolution mass spectrometer coupled with a high-performance liquid chromatography system to quantitatively analyze amino acids(More)
We investigated the OH-related formation routes of two astrophysically important molecules, H(2)O and CO(2), under relatively warm astrophysical conditions. OH radicals, together with other neutral species such as H, O, H(2), and O(2), were produced in H(2)O microwave-discharge plasma and cooled to 100 K before being deposited on an Al substrate at 40-60 K.(More)
Effects of CO2 on circulatory responses to laryngoscopy and endotracheal intubation were investigated in 16 patients under constant depth of enflurane anesthesia (1.2MAC) at different levels of CO2 (normocapnia, PETCO2: 40mmHg or hypercapnia, PETCO2: 60mmHg). Patients were randomly divided into two groups; normocapnia group (n = 8) and hypercapnia group (n(More)
Despite the rapid accumulation of structural information about organic materials, the correlation between the surface structure of these materials and their chemical properties, a potentially important aspect of their chemistry, is not fully understood. Here, we show that the amorphous or crystalline structure of a solid benzene surface controls its(More)
Experiments on the hydrogenation of CO on crystalline and amorphous ice at 15 K were carried out to investigate the structural effects of the ice surface. The effective rate of H atom addition to CO on the amorphous ice was found to be larger than that on the crystalline ice, while CO depletion on crystalline ice became larger after long exposure. We(More)
The anomalously low ortho-to-para ratios (OPRs) exhibited by gaseous water in space have been used to determine the formation temperature (<50 kelvin) of ice on cold interstellar dust. This approach assumes that the OPR of water desorbed from ice is related to the ice formation temperature on the dust. However, we report that water desorbed from ice at 10(More)
A 74-year-old male was operated for sigmoid colon cancer. Because of an agglutination of the patient's platelet, it was difficult to measure his platelet count under ethylene diamine tetra acetate (EDTA), heparin or citrate as anticoagulants with an automated cell counter. Even though there was a strong possibility of pseudothrombocytopenia, anesthetic(More)
Reported here is the first observation of the tunneling surface diffusion of a hydrogen (H) atom on water ice. Photostimulated desorption and resonance-enhanced multiphoton ionization methods were used to determine the diffusion rates at 10 K on amorphous solid water and polycrystalline ice. H-atom diffusion on polycrystalline ice was 2 orders of magnitude(More)