All issues
Volume 31 (1983)
- Issue 4 Pages 231-
- Issue 3 Pages 165-
- Issue 2 Pages 97-
- Issue 1 Pages 35-
Volume 31, Issue 2
Displaying 1-7 of 7 articles from this issue
- |<
- <
- 1
- >
- >|
REGULAR PAPERS
-
Tatsuo Arikawa, Ken-ichi Kanazawa, Seiji Tsurubuchi1983 Volume 31 Issue 2 Pages 97-104
Published: 1983
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSMeasurements of relative ion production yields in the Penning and dissociative ionizations of methane molecules on impact of metastable helium atoms have been carried out using a new crossed-beam apparatus, “Perfectron”. Due to the perfect focusing property of the perfectron, the total ion yield as well as differential ion yield of each reaction channel can be measured. Though the measurement is at present only preliminary and no attempt is made to discriminate between 21S and 23S states in the primary helium beam, obtained spectra are in good agreement with those of Cermak et. al. and of Herce et. al. in the measurement of total ion yields. The CH3+ ions are most abundant in contrast with electron impact where the parent CH4+ ions predominate. On the other hand, in the measurement of differential ion yields at 0° with respect to the methane beam, the parent CH4+ ions slightly predominate over the fragment CH3+ ions.View full abstractDownload PDF (539K) -
Tatsuo Arikawa, Hajime Higaki1983 Volume 31 Issue 2 Pages 105-110
Published: 1983
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSPeaks due to the rainbow scattering in elastic collisions of Ar+ ions with ground state CH4 molecules were observed in the differential cross section at laboratory energies from 20 to 80 eV superimposed on an oscillatory structure which is attributed to the accidental resonant electron transfer between collision partners. The rainbow peaks are clearly seen when the differential cross section is plotted in a reduced form. Indeed, each rainbow peak appears at the reduced scattering angle of about 290 eV-degrees. Classical calculations are fitted to the experimental cross sections with the use of the 12-6-4 potential. This potential contains an adjustable force parameter γ ranging from 1 to 0 according to how the charge-induced dipole interaction has a dominant role in the collision. The best fit is obtained when the potential depth is 2.7 eV and the interatomic distance at the potential well minimum is 2.4 Å for γ = 0.4.View full abstractDownload PDF (394K) -
Itsuo Katakuse, Toshio Ichihara, Hiromitsu Nakabushi, Takekiyo Matsuo, ...1983 Volume 31 Issue 2 Pages 111-114
Published: 1983
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSA compact primary gun of cold cathode discharge type for molecular SIMS is described. The size of the gun is 15 mm diameter and 31 mm long and 5 - 10 μA primary ion current was obtained. It could be mounted to a conventional FD source without any machine work of vaccum chamber.
Some SIMS spectra obtained with the gun up to m/z = 7000 are shown.View full abstractDownload PDF (368K) -
Yutaka Goto, Chikara Amano, Masao Inoue1983 Volume 31 Issue 2 Pages 115-120
Published: 1983
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSThis paper reports a microcomputer based data acquisition system for Fourier transform ion cyclotron resonance (FT-ICR) mass spectroscopy. The system has been developed for a prototype spectrometer constructed with a permanent magnet whose magnetic field strength is 6,200 gauss. The system cosists of two-channel sampling ports with sample-hold circuits, a multiplexer, an A-D converter, an I/O port and a logic circuit. The logic circuit starts data acquisition synchronizing with an external trigger pulse. The acquisition is then repeated for preset number of times to accumulate data for signal averaging. An operating program for the system was written in an assembly language in order to execute high-speed data acquisition and a program for FT-ICR experiments was written using BASIC. Resolution of 40,000 was obtained with CO+ ion in residual gas.View full abstractDownload PDF (364K) -
Atsushi Shigihara, Michihiko Ogata, Hiroshi Ichikawa1983 Volume 31 Issue 2 Pages 121-127
Published: 1983
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSPotential energies of proton migration and the H2, H2O, and NH3 elimination reactions in the protonated n-propanolamine were determined by MINDO/3. The elimination reactions in the protonated n-butanolamine were also examined and discussed in an attempt to explain the difference of the ratio of loss of water to loss of ammonia between these alcoholamines. Proton migration between carbon atoms in the protonated alkyl group was found to involve a low activation energy less than 84 kJ/mol but unlikely to take place because of other channels. Elimination of H2 was shown to take place from the C-protonated MH+ ion. There were several reaction paths for water and ammonia losses from the MH+ ion and the paths with hydrogen rearrangements were more likely to occur than the simple cyclization mechanism with the neighboring assistance of the hetero atom of the other end.View full abstractDownload PDF (385K) -
Yuzo Nakagawa1983 Volume 31 Issue 2 Pages 129-135
Published: 1983
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSFuranosesquiterpenes, isolated mainly from Lindra strychnifolia Vill. and other plants belonging to Lauraceae family, have chemically interesting structures. We have investigated the mass spectrometric behavior of the 22 furanosesquiterpenes using conventional and accurate mass spectral data. Metastable defocussing measurement was also carried out to confirm the fragmentation paths.View full abstractDownload PDF (331K) -
Hiroshi Kishi, Satoshi Kambe, Akio Sakurai1983 Volume 31 Issue 2 Pages 137-146
Published: 1983
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSMass spectra of benzopyranopyrimidine derivatives and their 4-acetylamino derivatives were measured and their fragmentation mechanisms were elucidated with the aid of the shifts of peaks by the substituent groups and deuterium labeling, and with the aid of the metastable peaks. High resolution mass spectra were also taken for some samples.
Benzopyranopyrimidine derivatives were very stable under electron impact ionization. Fragmentations of benzopyranopyrimidine ring contain characteristic cleavage of both 2-pyrone and pyrimidine ring. And the characteristic cleavage for this structure was also observed. 3,4-Dimethoxy group on the 2-aryl affected the main fragmentation of the benzopyranopyrimidine ring.
Elimination of ketene was the characteristic fragmentation for the 4-acetylamino derivatives.View full abstractDownload PDF (493K)
- |<
- <
- 1
- >
- >|