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Volume 22 (1974)
- Issue 4 Pages 233-
- Issue 3 Pages 173-
- Issue 2 Pages 121-
- Issue 1 Pages 1-
Volume 22, Issue 1
Displaying 1-14 of 14 articles from this issue
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Hiromitsu NAKABUSHI, Tadatetsu HATTORI, Koreichi OGATA1974 Volume 22 Issue 1 Pages 1-14
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSFor ion acceleration of the two-stage double-focusing mass spectroscope, which adjustment works are going on at Osaka University, a 100-kV dc stabilized power supply has been designed and constructed. The specifications given the supply are as follows; 1) the continuous variation of the output voltage from30kV to 100kV, 2) the maximum output current of about2.5mA, 3) the tolerances on drift and ripple, respectively, remaining within one part in104over a period of ten minutes and within two parts in105, and4) the output stability of less than five parts in105for fluctuation of±5percent.
The supply consists of two stages of regulation. The first stage regulator is of an oscillator-amplitude modulation type incorporating a Cockcroft-Walton type rectifier and stabilizes its output voltage to within one part per thousand less. The second stage regulator is of a conventional series tube type and accomplishes further improvement of two orders of magnitude on the stability. Thus, the final degree of stabilization is obtained to be of the order of one part in105.
As a typical example, a steady long-term stability at the output voltage of100kV is well estimated to be3-5parts in105averaging over periods of an hour from the observation ranging over about eight hours.View full abstractDownload PDF (4331K) -
Isao NISHI1974 Volume 22 Issue 1 Pages 15-23
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA mass spectrometric system equipped with the multi-collectors and peak selectors is investigated. The principal features of this method are to make a rapid wide mass range scanning by the rapid voltage scanning of shorter range and to make a simultaneous recording of multi-components with fast response through the multi-channel peak selectors. The graphic representation of ion optics is presented for determining the design parameters. Practical applications are given on the respiratory gas analysis. Several technical key points such as determining the accurate collector position, the response of the system, and the characteristics of the gate circuit which is the central part of the peak selector, are discussed with the mind of applying this system to the respiratory gas analysis.View full abstractDownload PDF (5090K) -
Ginji FUJISAWA, Hitoshi HASIMOTO, Matae IWASAKI, Shigeo TSUJIMURA1974 Volume 22 Issue 1 Pages 25-34
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA mass spectrometer for the analysis of gas samples containing uranium hexafluoride and fluoride impurities was constructed by modification of the ionization chamber and gas inlet system of a Hitachi RMU-6L mass spectrometer. The treatment of the system by fluorine was effective to remove the impurities, reactive for uranium hexafluoride. After flushing the system by uranium hexafluoride, a liriear relationship between the UF+5 peak height and the pressure of urariium hexafluoride in the sample gas reservoir was obtained.View full abstractDownload PDF (3163K) -
Fusafumi NAKAO, Terumasa YAMAMOTO1974 Volume 22 Issue 1 Pages 35-44
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA programable quadrupole mass spectrometer has been developed to make continuous observation of the gaseous pollutant materials and respiratory gases, . and to make continuous monitoring of the gaseous species present in the high vacuum atmosphere. The equipment has a multi-channel high speed programable scanner which consists of high speed IC switching circuits and accurate mass selector controls. A detailed description of the circuit and its function are given. A maximum scan speed is1msec per amu in the case of100channels. The equipment has a reproducibility of better than99. 6%and a detection limit of10ppm for SO2of the pollutant gases in the chimney flue.View full abstractDownload PDF (771K) -
Yasuaki ESUMI, Sakae SATOOKA1974 Volume 22 Issue 1 Pages 45-54
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSBy the adoption of an ion current stabilizer which keeps the ion current constant during measurement, we constructed a mass spectrometer which directly indicates the value of the isotopic abundance ratio without any calculations. Although this method included two kinds of technical difficulties, these difficulties were overcome and our aim has been attained. The ion current stabilizer keeps the ion current of the larger peak constant by controlling the emission current of electrons. In the measurement of samples which containing0. 2-0. 5atomic percent of36Ar, the precision is maintained at three figures, though this method includes the error consisting of the theoretical error, the overlapping of its background and the error from the mass discrimination effect. A great many samples could be measured conveniently, precisely and continuously. We could widely lessen the labor of the measurement by use of an automatic sample introduction equipment with this apparatus.View full abstractDownload PDF (614K) -
Tatsuya SEKI, Ichikazu HAYASE1974 Volume 22 Issue 1 Pages 55-59
Published: March 31, 1974
Released on J-STAGE: March 01, 2011
JOURNAL FREE ACCESSRb-Sr isochrons were obtained on the cretaceous acid volcanic rocks of Himeji district, Hyogo prefecture, Japan. The isochron of the Tenkadaiyama forInation, younger rocks in this area, yielded T=67.5±5. 9m. y. and (87Sr/86Sr) . =0.7105±0.0006by both whole rock specimens and separated fractions. On the contrary, it was determined two ages on the Aioi formation, older extrusive rocks. One age was obtained by the whole rock isochron which gave T=105±16m. y. and (87Sr/86 Sr) 1= 0. 7057±0.0008. The other was obtained by internal isochrons. Two rock specimens of the Aioi formation were separated for internal isochrons. One gave T=70±7m.y. and (87Sr/86Sr) =0.7079±0.0007, and the other gave the same age and higher initial strontium ratio, respectively. This indicates that the Aioi formation erupted at about100m. y. BP and was influenced at about70m. y. BP by the eruption of the Tenkadaiyama formation which caused re-equilibration of the Rb-Sr system in the mineral parts of the Aioi formation to give a younger internal isochron age.View full abstractDownload PDF (468K) -
Minoru KUMAKURA, Akihiro ITO, Toshio SUGIURA1974 Volume 22 Issue 1 Pages 61-70
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe ion-molecule reactions in the systems including ethylene oxide have been studied at thermal ion energies by means of the ion trapping technique using a modified time-of-flight mass spectrometer. Details of the ion source constructed in this laboratory have been described. The performance of this modified ion source has been examined by the measurement of the ion-molecule reactions in methane. The following major ion-molecule reactions have been identified to be occurring in ethylene oxide, with the measurements of the ionization efficiency curves using the RPD technique for determination of the precursors in the reactions. (All rate constants in cm3/molecule.sec.) C2H4O+C2H4O→C2H5O++C2H3O, k=1.45×10-10, CHO++C2H4O→C2H5O++CO, k=2.05×10-9, CH3++C2H4O+→C2H3O++CH4, k=2.10×10-10.By the experiments using simple hydrocarbons including ethylene-d4as the additive, the sequence of the reactivity for the protonated ion formation and the charge transfer reactions from simple hydrocarbon ions to the ethylene oxide molecule have also been studied.View full abstractDownload PDF (907K) -
Yuji ASAKURA1974 Volume 22 Issue 1 Pages 71-77
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe mass spectroscopic cracking pattern with its rich informations serves as a reliable basis for identification of organic compounds . Identification on the basis of the gas chromatographic retention time alone is much less reliable . If a substance can be converted by a suitable treatment into a mixture of many substances, the mixture will yield a gas chromatogram with n peaks. This gives2-1informations, namely, n retention times plus -1 relative peak areas, thus making identification more reli able. By thermal decomposition by an electrically heated filament, for example, ethylether, methyl-thioether, n-pentane, n-hexane, iso-hexane and cyclohexane gave respectively6, 8, 4, 6, 7, and5peak pyrolysis chromatograms . Effects on these peaks of changes of several experimental conditions were studied. Within the extents of the changes performed, retention times always remained unaffected. The area of each peak of the pyrolysis chromatogram of a substance changed differently with filament temperatures, namely, steady increase, leveling off, decrease through a maximum, or steady decrease. These temperature-dependence curves plotted all on a single graph will reveal a feature especially suitable for identification. This general feature of such a composite graph was found, at least in the case of n-pentane, essentially independent of the filament material(tungsten or platinum)and shape(hair-pin or spiral). With increasing sample size up to9. 3μl. all the five peaks of the pyrolysis chromatogram of cyclohexane increased in area linearly until about7. 3μl. For the same sample size(7μl)of various benzene to cyclohexane ratio mixtures benzene always favored the thermal decomposition of cyclohexane.View full abstractDownload PDF (806K) -
Masahiko TSUCHIYA, Yuji HORII1974 Volume 22 Issue 1 Pages 79-85
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSMass spectra of excess-kinetic-energy ions(KE ions)formed under electron impact have been studied by using a commercial mass spectrometer with the modified ion source. Parent ions of KE ions may be so much excited than those of thermal-energy ions that they may decompose more quickly and give much simple cleavage ions and less rearrangement ions. Therefore the mass spectrum of KE ions must be different from the ordinary mass spectrum. Several compounds of alcohols and ethers have been studied. Simple relations have been found between the mass spectra of KE ions and the structure of these compounds. Generally, fragment ions which are smaller than a half of a molecule can be observed as KE ions and the terminal groups of a compound, such as CH3CO, -CH2OH, HCO-, C2H5-and so on, give the intense peaks. It has been proved that the mass spectra of KE ions show less rearrangement and are useful for the structure determination of organic compoundsView full abstractDownload PDF (561K) -
Takeshi MURATA, Seiji TAKAHASHI1974 Volume 22 Issue 1 Pages 87-94
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThis paper refers to an analytical technique by a tandem DTA-GC-MS combined system and describes our experiments to analyze polyacrylonitrile(PAN)resin and Nylon6in different atmospheres of air and inert gases. The DTA-GC-MS tecnique not only provides informations on the behaviors of samples under heating but also qualitatively determines the gases evolved during the process of heating. The GC-MS identified HCN evolved from the PAN resin samples and HCN and NH, evolved from a Nylon6sample using a Chromosorb103column, and acetonitrile, vinyl-acetonitrile, methylbutene, cyclohexane, toluene, pro panenitrile and2-methyl-propanenitrile evolved from the PAN resin sample, using a PEG-20M column.View full abstractDownload PDF (727K) -
Toru UENO, Toshiyuki SUEYOSHI, Yoshinobu TAKEGAMI1974 Volume 22 Issue 1 Pages 95-101
Published: March 31, 1974
Released on J-STAGE: July 05, 2011
JOURNAL FREE ACCESSA general data processing for deduction of masspectra detected on a photographic plate through the use of the computer of large core-size of the public computation center has been described. The procedures involve identificationof the reference peaks (PFK), exact mass calculation, check and/or subtraction of the background, 13 C-check, selection of abundant neutral fragment loss, conversion of the exact mass of each peak into an elemental composition, and check of neutral fragment loss for each peak. If the sample is a mixture, the undesired component (s) can be checked and/or subtracted by the use of cumulative masspectra of their pure component (s) . These computations can be achieved within relatively short computation time of3min through the use of FACOM 230-60.View full abstractDownload PDF (712K) -
Toru UENO, Toshiyuki SUEYOSHI, Kenji ASFIIDA, Yoshinobu TAKEGAMI1974 Volume 22 Issue 1 Pages 103-107
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSAn attempt to approximate the peak height determined by magnetic scanning from the intensity of ions detected on a photographic plate through the use of a mass spectrograph of the Mattauch-Herzog type has been empirically studied. The approximation has been performed by the use of calibration plots of logarithm of exposures against the reciprocal of the transmittance determined by a photodensitometer and by the use of a mass correcting factor . Thevalidity of the procedures was examined for the spectrum of choresterol which was measured according to a routine manner, giving an acceptable compromise between the two intensities.View full abstractDownload PDF (351K) -
Toru UENO, Toshiyuki SUEYOSHI, Eiji TANAKA, Ryoichi JINKAWA, Akihisa H ...1974 Volume 22 Issue 1 Pages 109-114
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe procedure by which the peaks arising from the background can be checked and subtracted has been reported. The mass spectra of the background and sample were detected in separate runs of the plate under controlled conditions, and were stored in separate dimensions in a computer. The checks and subtractions were carried out on the basis of difference in exact masses and of the ratio of intensities. A similar procedure was also be applied to the checks and subtractions of the reactants(sample background)in a reaction mixture to afford only a spectrum of the species produced by the reaction. The subtractions of the background and sample background were examined for a mixture of benzophenone(I), 2, 4-dinitrophenylhydrazine(II)and2, 4-dinitrophenylhydrazone of I being taken I and II as sample backgrounds. The utility and limitation of the procedure have been described and discussed.View full abstractDownload PDF (495K) -
Toru UENO, Kenji ASHIDA, Eiji TANAKA, Yoshinobu TAKEGAMI1974 Volume 22 Issue 1 Pages 115-120
Published: March 31, 1974
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe less volatile components of the[diethyl aluminum(III)chloride?water(20: 1)]system were deduced from mass spectrometry. Ions which bear two aluminum atoms were classified to one of the proposed skeletal structures on the basis of several established facts: (1)aluminum atoms hardly change their valence during fragmentations, (2)the stability of bridge bondings increases in the order ethyl<chlorine<oxygen, and(3)even-electron ions are far more abundant than odd-electron ions. Then, the ions which bear two oxygen atoms were classified to the clusters bridged by two oxygen atoms, and the ions which bear only one oxygen atom to the clusters bridged by both oxygen and chlorine atoms. Since the transformation of an electron-deficient oxygen-bridge into a normal oxygen bond did not occur appreciably during fragmentations, the presence of ions of a certain skeletal structure could be taken as a reflect of the presence of species of the same skeletal structure in the mixed components of the sample. Cyclic sixmembered skeletal structures were proposed for ions which bear Al3O3. The mass spectrum of aluminum(III)chloride has confirmed the assumption: oxygen-bridged clusters are far more stable than chlorine-bridged clusters.View full abstractDownload PDF (552K)
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