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Volume 41 (1993)
- Issue 6 Pages 297-
- Issue 5 Pages 253-
- Issue 4 Pages 191-
- Issue 3 Pages 159-
- Issue 2 Pages 73-
- Issue 1 Pages 5-
Volume 41, Issue 4
Displaying 1-5 of 5 articles from this issue
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REGULAR PAPERS
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Keisuke NAGAO, Yayoi N. MIURA, Masako SHIMA1993 Volume 41 Issue 4 Pages 191-209
Published: 1993
Released on J-STAGE: July 20, 2007
JOURNAL FREE ACCESSNoble gas concentrations and isotopic ratios were measured for 12 Japanese chondrites. Cosmic-ray exposure ages and gas retention ages obtained for these chondrites are discussed with those for other Japanese chondrites already reported. Cosmic-ray exposure ages of L chondrites range from 5 to 60 Ma without clear cluster, while H chondrites belong to two clusters around 7 and 30~40 Ma. More than half of L chondrites have U, Th-He, and K-Ar ages lower than 3.0 Ga, indicating gas loss by shock event. The concentrations of trapped Ar, Kr, and Xe agree with those inferred from correlation reported between the trapped gas content and the petrographic type. Shiraiwa (H4), find, is the only exception, whose Xe concentration is in the range of type 6. Noble gas data confirm that Kariyasu is a fragment of the Mino (Gifu) metrorite shower, and Hashima and Kasamatsu are different falls. The enstatite chondrite Kishima has a low concentration of subsolar noble gas component. Because the measured concentrations of the subsolar type noble gases are lower than reported ones in Fukutomi (L4-5), the carrier which provide such noble gases should be heterogeneously distributed in Fukutomi.View full abstractDownload PDF (1289K) -
Shigetomo KITA, Hokotomo INOUYE1993 Volume 41 Issue 4 Pages 211-223
Published: 1993
Released on J-STAGE: July 20, 2007
JOURNAL FREE ACCESSA time-of-flight analyzer with the path length 2.2 m has been constructed and tested by employing a pulsed ion gun. The optimum time resolution achieved in this analyzer was t/Δt = 6500. The time-of-flight apparatus was used for velocity analysis of fast Li atoms produced by charge exchange reactions in moderate energy Li+-Li collisions. The pulsed alkali-ion beams with time duration of a few ns have been formed by chopping the well-collimated continuous beams. For the pulsing a negative square-wave voltage was applied to a pair of condenser plates.View full abstractDownload PDF (793K) -
Cross Section Measurement of C2- and C2H- Ion Formation by Double Electron Transfer in One CollisionShigeo HAYAKAWA, Norihisa TERAZAWA, Toshio SUGIURA1993 Volume 41 Issue 4 Pages 225-234
Published: 1993
Released on J-STAGE: July 20, 2007
JOURNAL FREE ACCESSUsing a beam-gas technique, double electron transfer cross sections of non-dissociative C2- and C2H- ion formations with a Cs target were evaluated to be 7.03 × 10-18 and 1.87 × 10-18 cm2 at laboratory energy of 3.0 keV, respectively. The cross sections of C2- and C2H- ion formation decreased with the decrease of the laboratory energy, becoming 2.15×10-18 and 3.41 × 10-19 cm2 at 0.7 keV, respectively. The cross sections of double electron transfer with K or Na targets were estimated to be less than 2 × 10-20 cm2 at collision energy between 0.7 keV and 3.0 keV. The energy dependence and the magnitude of the cross sections were compared with an adiabatic criterion and Landau-Zener approximation. The Landau-Zener approximation gave the cross sections which were one order of magnitude larger than the experimental value. This difference between the calculated value and the experimental value would be explained from the influence of intermediate pseudopotential crossings between an ion pair state and excited ion molecule states.View full abstractDownload PDF (669K) -
Fumio TOBA, Masayuki ANDO, Tsukasa HAMADA, Norio AWATA, Toshinobu TUDA ...1993 Volume 41 Issue 4 Pages 235-243
Published: 1993
Released on J-STAGE: July 20, 2007
JOURNAL FREE ACCESSA gas chromatography-mass spectrometric method was employed for the determination of the antispasmodic drug, eperisone, in plasma. Excellent sensitivity was achieved by the selection of the base ion peak at m/z 98 of eperisone and a suitable internal standard, tolperisone, and by using a cyanopropylphenyl-bonded fused-silica capillary column. The lower limit of sensitivity was 10 pg/ml with a signal-to-noise ratio of 3. Another internal standard, decadeuterium labelled eperisone, was inferior to tolperisone in terms of accuracy and reproducibility at low levels of eperisone. The present method allows the determination of eperisone in human plasma after an oral administration of eperisone hydrochloride.View full abstractDownload PDF (432K) -
Yoshinori INOUE, Katsuhiko KAWABATA1993 Volume 41 Issue 4 Pages 245-252
Published: 1993
Released on J-STAGE: July 20, 2007
JOURNAL FREE ACCESSInductively coupled plasma mass spectrometry (ICP/MS) was applied to analysis of organotin compounds after separation by micellar liquid chromatography (MLC). Chlorides of dimethyltin (DMT), trimethyltin (TMT), dibutyltin (DBT), tributyltin (TBT), diphenyltin (DPT), triphenyltin (TPT) were separated within 20 minutes by using tris(hydroxymethyl) aminomethane lauryl sulfate as a mobile phase and butyl group bonded silica gel as a stationary phase. Subsequently eluates were directly introduced into ICP/MS and detected at m/z=120. Detection limits for six organotin compounds were from 24 to 51 pg as Sn element. The dynamic range was over 104, from 1 μg/l to 10 mg/l. The repeatability was better than 3% of the relative standard deviation (RSD) for all organotin compounds.View full abstractDownload PDF (455K)
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