Journal of the Mass Spectrometry Society of Japan
Online ISSN : 1880-4225
Print ISSN : 1340-8097
ISSN-L : 1340-8097
24 巻, 4 号
選択された号の論文の8件中1~8を表示しています
  • 大橋 守, 中山 登, 工藤 均, 山田 修三
    1976 年 24 巻 4 号 p. 265-270
    発行日: 1977/01/31
    公開日: 2011/07/05
    ジャーナル フリー
    In Beam EI spectra of amino acids are described. To obtain IBEI spectra a, sample was loaded on an end of the quartz tip of a modified direct inlet probe and inserted until the electron beam was interrupted. Except cystine and arginine IBEI spectra of amino acids so far studied always exhibited clearly M+1peaks. Relative intensities of M and M+1 peaks in IBEI and conventional EI spectra are listed in Table1. The complete spectrum was apparently a combination of a conventional EI spectrum and the M+1peak. This technique is quite useful for detection of M+1peaks of thermally unstable compounds such as creatine or glutamic acid of which conventional E1 spectrum scarcely exhibits the M or M+1peak. The spectral features are somewhat similar to those obtained from closed source instruments. In the case of phenylalanine, effects of measuring conditions such as source temper ature, ionization voltage, sample position and time factor on the ratio of[M+1]/[M]were examined. When a sample was mixed with ammonium chloride, the M+1peak in the IBEI spectrum was completely suppressed, which must be useful for identification of the M+1peak.
  • HIDEKI KAMBARA, ICHIRO KANOMATA
    1976 年 24 巻 4 号 p. 271-282
    発行日: 1977/01/31
    公開日: 2011/03/01
    ジャーナル フリー
    Some organic compounds are investigated by atmospheric pressure ionization(API)mass specmetry. Organic molecules are ionized by proton or ion transfer reactions to produce many cluster ions. These ions can be reduced to quasimolecular ions by means of collisional dissociation at high pressure. Relation curves of ion intensity and sample concentration are determined. for the ion producing process. In most cases, those for organic compounds are linear in a relatively small sample size region. Ionization efficiency is so high that the detection limits is influenced only by overallion transmission efficiency.
  • ―ケトン誘導体―
    久留 正雄, 山川 浩司
    1976 年 24 巻 4 号 p. 283-293
    発行日: 1977/01/31
    公開日: 2010/06/28
    ジャーナル フリー
    Mass spectral fragmentation pathways of ketone derivatives of[3]-and[4]-(1, 1')ferrocenophanes are presented. It has been shown that the ions formed by decarbonylation from the molecular ions of6-and7-ketones and6, 7-diketones have the bridged structure by ring contraction.
  • 江口 鎮子, 永井 君子, 中山 充, 林 修一
    1976 年 24 巻 4 号 p. 295-306
    発行日: 1977/01/31
    公開日: 2010/06/28
    ジャーナル フリー
    Ion kinetic energy spectroscopy(IKES)provides new and useful information on the structure of ions formed by mass spectrometer. This method was applied to the distinc tion of isomeric monoterpene pairs whose mass spectra are nearly identical. It is shown that the IKE spectra can be used for such isomers, which was exemplified by the case of borneol and iso-borneol.
  • 桜井 寛, 立松 晃, 中田 尚男
    1976 年 24 巻 4 号 p. 307-313
    発行日: 1977/01/31
    公開日: 2010/06/28
    ジャーナル フリー
    The2E doubly charged ion mass spectra of several aniline derivatives were recorded. For most compounds, substituents affect fragmentation pathways including those of the benzene ring itself. It is shown that some isomer pairs can be differentiated by comparing these spectra even though their conventional spectra are almost identical. Some aspects of structures and fragmentations of doubly charged ions are also discussed.
  • 飯田 芳男, 岡田 静子
    1976 年 24 巻 4 号 p. 315-320
    発行日: 1977/01/31
    公開日: 2011/03/01
    ジャーナル フリー
    A simple and sensitive method forthe determination of15impurities in benzene by GC-CIMS is presented. One to ten μl of sample is injected into a Finnigan3300EGC-CIMS instrument equipped with a1.5m×2mm i. d. glass column packed with5%squalane(for2-methylpentane, 3-methylpentane and n-hexane)or5m column packed with5%PEG400(for the other12impurities)and the mass fragmentograms of the specific peaks due to QM+or(M+29)+are recorded. The peaks used are as follows: m/e69for cyclopentane, m/e71for2-methylbutane, m/e77for carbon disulfide, m/e83for methylcgclopentane and cyclohexane, m/e85for2-methylpentane, 3-methylpentane, n-hexane and thiophene, m/e97for methylcyclohexane, m/e93for toluene, m/e135for ethylbenzene and p-, m-, o-xylene. Methane is used both as carrier and reactant gas. Because of high selectivity and sensitivity of the proposed method, satisfactory results were obtained without any preconcentration and the separation of cyclopentane from2-methylpentane and of carbon disulfide from cyclohexane by GC. The determination limit was5-50pg with a precision of about5%. The total impurities in five samples which are all reagent chemicals were found to be0.013-0.28%.
  • 原口 信一, 新家 敏弘, 水野 悳夫, 久原 とみ子, 松本 勇
    1976 年 24 巻 4 号 p. 321-329
    発行日: 1977/01/31
    公開日: 2010/06/28
    ジャーナル フリー
    Both organic acids and amino acids in urine were analyzed to find the metabolic disorders and the congenital metabolic diseases, as earlier as we can, by the GC-MS-COM screening system which is able to screen many kinds of diseases with one screening, in a small sample, rapidly and exactly. After the simple treatment which means the extraction of acids with diethyl ether at pH1and the elution of amino acids through the AG-50W-X12cation exchange resin, the sample of urine corresponding to5mg of creatinine was subjected, as a fundamental experiment, to the GC-MS-COM system equipped with one2m glass-coiled column packed with3%OV-17. When a patient's urine was analyzed in order of the procedure, a large peak which was not detected in normal urine, was identified as a methylmalonic acid by the analysis of the mass spectrum.
  • 中嶋 康雄, 高橋 貞夫, 望月 康平, 野田 保
    1976 年 24 巻 4 号 p. 331-336
    発行日: 1977/01/31
    公開日: 2010/06/28
    ジャーナル フリー
    The integration method of recording the chromatogram for GC-CI-MS system is descrived. The chromatogram of a trace component, especially of less than 100ng, is hardly obtainable by the ordinary TIM system. With this integration TIM system(ITIM), the chromatograms of GC-CI mode are improved by integrating the ion sighal of individual masses except for the CI reactant ions in CI mass spectra. The chromatograms of methyl stearate, using 50ng and 20ng respectively, are shown by GC-CI-MS. The calibration curve of methyl stearate in the range of 2 to 100ng shows good linearity of this ITIM. Several mixtures are successfully analyzed by this technique.
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