Publications by authors named "Y Ohrui"

Drift tube ion mobility spectrometry with a novel atmospheric electron emission (AEE) source was developed for determination of gaseous and blister chemical warfare agents (CWAs) in negative mode. The AEE source was fabricated from an aluminum substrate electrode covered with 1 μm silver nanoparticle-dispersed silicone resin and a thin gold layer. This structure enabled stable tunneling electron emission upon the application of more than 11 V potential under atmospheric pressure.

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The Raman spectra of twenty-two chemical warfare agents (CWAs) were measured: eleven nerve agents and their precursor, five blister agents, three lachrymators, one choking agent, and one vomit agent, in liquid or solid state in colorless transparent vials were analyzed using a portable Raman spectrometer, Xantus-2 from Rigaku Corporation, equipped with selectable excitation lasers (785nm and 1064nm). With 785nm excitation, characteristic Raman spectra composed of many sharp peaks were observed for twenty CWAs, but nitrogen mustard 3 (HN3) and adamsite (DM) did not show particular peaks owing to broad and intense mountain-like baselines. With 1064nm excitation, Raman spectra similar to those with 785nm excitation were observed for the twenty CWAs, where the wavenumbers of the peak tops and comparative heights were similar to those with 785nm excitation.

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A field-portable gas chromatography-mass spectrometry (GC-MS) system (Hapsite ER) was evaluated for the detection of nonvolatile V-type nerve agents (VX and Russian VX (RVX)) in the vapor phase. The Hapsite ER system consists of a Tri-Bed concentrator gas sampler, a nonpolar low thermal-mass capillary GC column and a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump. The GC-MS system was attached to a VX-G fluoridating conversion tube containing silver nitrate and potassium fluoride.

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The mirror gap of a Fabry-Perot interferometer was stabilized with two laser diodes; one locked to the line frequency 385,243,555.14445 MHz of the F=3<--1 in 5D(3/2)<--5S(1/2) (87Rb) and the other to the 385,284,566.3663 MHz of the F=4<--2 in 5D(5/2)<--5S(1/2) (87Rb) [Opt.

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