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Volume 23 (1975)
- Issue 4 Pages 237-
- Issue 3 Pages 161-
- Issue 2 Pages 105-
- Issue 1 Pages 1-
Volume 23, Issue 1
Displaying 1-12 of 12 articles from this issue
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HISASHI MATSUDA1975 Volume 23 Issue 1 Pages 1-7
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA new ion optical system is proposed for a simple double focusing mass spectrometer. The apparatus consists of a parallel plane condenser, a doublet electrostatic Q lens and a simple homogeneous magnet having pole pieces of rectangular shape.(γm=30cm, φm=30°, ε′=ε″=15°). A weak magnetic field(∼5000 gauss)is sufficient to analyze ions of A∼1000 because γm is large. Stigmatic double focusing is obtained by the doublet Q lens and the plane condenser. The adjustment of the energy focusing as well as the directional focusing can be achieved by changing potentials on the electrodes of two Q lenses. Therefore, no mechanical adjustment is necessary at all. Several examples of suitable parameters are shown, and the method of the electrical focus adj ustment is explained. The second order focusing character is also described.View full abstractDownload PDF (579K) -
HIROSHI NISHIMURA, JUN OKANO1975 Volume 23 Issue 1 Pages 9-14
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSAn ion source to get an ion beam of oxygen was constructed. A stable ion beam of oxygen was obtained. The current and the diameter of the beam were 1.2×10-7 A and 100μm, respectively. The ion source was attached to a secondary ion mass spectrometer as the primary ion source. The preliminary measurements of the isotopic ratios of chromium, iron, and nickel were performed for the sample of stainless steel. The relative sensitivities of Ti, V, Cr, Mn, Co, and Ni to Fe were obtained by the use of the standard sample of low alloy steel(NBS, No. 466). The results were compared with those obtained by the primary ions of argon. It was found that the differences of the relative sensitivities among these elements were small for oxygen primaries compared with that for argon primaries.View full abstractDownload PDF (422K) -
EIICHI SAGAWA, TOMIZO ITOH1975 Volume 23 Issue 1 Pages 15-22
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA bulk type CEM is more advantageous to ultra-high vacuum applications than a thin film type CEM because of its temperature stability. We studied the gain and fatigue of this new type of CEM as an ion detector. The gain is less than that of the commercial thin film type because of its shape and the material used, but it has a wider dynamic range. Its gain fatigue with increase of total counts is comparable to that of the thin film type.View full abstractDownload PDF (543K) -
MASAO SUGA, YOSHIAKI HIDAKA1975 Volume 23 Issue 1 Pages 23-32
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA quadrupole mass spectrometer was connected to a shock tube. An ion source for fast reactions was designed. The characteristics of the ion source were examined in various conditions. The rise time was mainly dependent on the ion repeller voltage, the electron current, and the position and structure of the ion source. The lag time was also dependent on the ion repeller voltage and the position of the ion source. It was found that the rise time and the lag time depended on the behavior of both ions and neutral molecules in the vacuum chamber.View full abstractDownload PDF (2702K) -
TOMOKO MAKINO, REISUKE GENSHO, MASATAKE HONDA1975 Volume 23 Issue 1 Pages 33-39
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESS10Be was produced by neutron irradiation of boron nitride and beryllium metal. As for beryllium metal sample, 10Be was enriched by an isotope separator at the Institute for Nuclear Study. As for boron nitride sample, an isotopic abundance of 10Be was measured by the surface ionization method. The mass spectrum was obtained for 3.0×10-9g of 10Be in the presence of the same quantity of 9Be, mounted on a rhenium single filament with silica-gel. The amount of beryllium was determined by isotope dilution analysis. The discrimination factor of beryllium was estimated to be 1.05 per one mass unitView full abstractDownload PDF (589K) -
TADASHI SHIMAMURA, OKIO ARAI, KOICHI KOBAYASHI1975 Volume 23 Issue 1 Pages 41-47
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA preliminary experiment for study on cosmic dust was carried out with a new ion counting technique for mass spectrometry. The new technique made us possible to measure an isotopic composition of magnesiumin a less than 0.1μg-sized particle wkich had been collected in upper atmosphere or in the deep sea sediment. Since organic substances disturbed the mass peaks of magnesium, the measured values are not entirely reliable. Further experimental study to eliminate the organic peaks is in progress.View full abstractDownload PDF (693K) -
SHUZO TAMURA1975 Volume 23 Issue 1 Pages 49-59
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA technique to increase and stabilize the ion production of molybdenum and some other elements has been developed in their isotopic analysis by single-filament surface ionization mass spectrometry. A mixture of the element (5-100μg, dilute sulfuric acid solution)and five to ten as much glycerol(5v/v% aqueous solution purified by ion exchange)was mounted on a ribbon filament and was charred in air to slightly wet tar, and then heated in the mass spectrometer ion source under a vacuum of-5×10-7 Torr to appropriate temperatures by slowly increasing the filament current. As the filament material, rhenium ribbon was suitable for Mo and Hf, and tantalum ribbon for Cr samples. The sample coated in the form of oxo-compounds was reduced possibly through intermediate or direct carbonization during mass spectrometry and the sample pretreatment outside or inside the instrument was shortened. Stable ion currents of 10-13; to 10-11 A for Mo+, Hf+, and Cr+ ions were obtained and found to be usable in routine isotopic analysis.View full abstractDownload PDF (4734K) -
SHIGERU IKUTA, KENJI YOSHIHARA, TAKANOBU SHIOKAWA1975 Volume 23 Issue 1 Pages 61-67
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSCalculation on the breakdown curves of molecular ions has been done applying molecular orbital treatment. In this treatment the following assumption is adopted: the scission probability of each bond is proportional to the partial bond population of the corresponding bond in the particular occupied MO which correlates to the particular ionization. The calculated breakdown curves were compared with those experimentally obtained after charge exchange with various positive ions. The fairly good agreement between them is obtained, if additional contributions of the processes of electron redistribution and secondary scission are considered. The degree of the transition from electronically excited mole cular ion to the lower exited one was also estimated.View full abstractDownload PDF (550K) -
II. Simultaneous Analysis of Multi-components of Trace ConcentrationYOSHIAKI UCHIDA, YASUJI KOYAMA, TAKASHI CHIHARA, KOGORO MAEDA1975 Volume 23 Issue 1 Pages 69-78
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSApplicability of the mass filter system to simultaneous analysis of multi-components was examined by introducing a gaseous sample containing ppm order components of three sulfides CS2 CH3SH and H2S in N2 diluent. The sample gas was prepared by using a standard gas effluent system based on the permeation principle and introduced directly to the analyzer system through a glass capillary leak. Reasonably good response be tween the peak heights and the concentrations was obtained for the three components in the range studied, 3087640.3ppm for CS2, 2087645ppm for CH3SH and 3087643ppm for H2S. Deviations from the linear response, however, were found in the range below 287643ppm for the CH3SH and H2S components. The deviations probably arise from adsorption and reaction of the components on the inner surfaces of the glass and stainless steel pipe for the sample introduction. The present results indicate the good adaptability of the mass filter system to simultaneous analysis of multi-components and also suggest the importance of sample introduction procedure in trace component analysis.View full abstractDownload PDF (1176K) -
HIROHITO TONE1975 Volume 23 Issue 1 Pages 79-85
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSStudies on the analysis of heavy water concentrations by fast neutrons were carried out. When heavy water is irradiated by fast neutrons, there is a correlation between the heavy water concentration and the amount of thermal neutrons in heavy water. Ten mCi of 241Am-Be was used as a fast neutron source, and the heavy water volumes used in the experiments were 1, 2 and 5 liters. It is found from the experimental results that there are following relationships between the heavy water concentration(C)and counting rate(N)of thermal neutrons in heavy water: N=K1 exp(-PC)at the concen-tration of less than 80mole%, and N=-K2C+q at the concentration of greater than 80mole%. The sensitivity of this heavy water analysis, which is defined as the minimum change of the heavy water concentration to be detected, is 0.5mole% on the average. Boron and ur anium, which are neutron absorbers in heavy water, decrease daccuracy of the analysis, and the effect of the void was also determined.View full abstractDownload PDF (651K) -
MAMORU OHASHI, KAZUO TSUJIMOTO, YASUO SHIDA, YASUJI YAMADA1975 Volume 23 Issue 1 Pages 87-92
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe mass spectrometric behavior of 1-phenyl-4, 5, 6, 7-tetrahydrobenzotriazole and its seven membered analog is described. The principal fragmentation process of the molecular ions is loss of nitrogen. It was concluded from the results of deuterium labeling and accurate mass measurements that the subsequent fragmentation of the M-N2 ions proceeds via isomerization to the ring-contracted ketenimine ions by the Wolff rearrangement, in sharp contrast to the case of 1-phenylbenzotriazole.View full abstractDownload PDF (448K) -
MITSUO UCHIDA1975 Volume 23 Issue 1 Pages 93-99
Published: March 31, 1975
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe mass spectral fragmentations of 2-, 3-and 4-picoline N-oxides were studied at various sample pressures. The relative intensities of the fragment ions greatly depend upon the sample pressure even at pressures in the normal working range. From the patterns of logarithmic ion intensity-pressure curves, the formation mechanisms of the fragment ions are classified into four types of reactions. They are the unimolecular decomposition of the molecular ion, the fragmen-tations including some intermediate ions, the formation of secondary ions, and the fragmentations including two or three kinds of these reactions. The fragmentations including the intermediate ions may occur in the first step of decompositions concerned with the skeletal rearrangements of the molecular ion.View full abstractDownload PDF (561K)
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