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Volume 34 (1986)
- Issue 6 Pages 339-
- Issue 5 Pages 257-
- Issue 4 Pages 197-
- Issue 3 Pages 139-
- Issue 2 Pages 71-
- Issue 1 Pages 13-
Volume 34, Issue 3
Displaying 1-6 of 6 articles from this issue
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REGULAR PAPERS
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Shigeru Ikuta1986 Volume 34 Issue 3 Pages 139-146
Published: 1986
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSHydrogen bond energies of the protonated bases (OH3+, CH3OH2+, and (CH3)2OH+) with one water molecule were computed using the Hartree-Fock MO method with the 6-31G* basis set. The corrections due to the electron correlation and zero-point vibrational energies were performed. In the relationship between the hydrogen bond energies and the hydration energies of the protonated bases, methyl-substituted-OH3+ and -NH4+, a single straight-line was obtained, although some deviations from the line were observed in the data on the fully methylated protonated bases, (CH3)2OH+ and (CH3)3NH+.View full abstractDownload PDF (483K) -
Shigeo Hayakawa, Akira Matsumoto, Masaki Yoshioka, Shingo Matsuoka, To ...1986 Volume 34 Issue 3 Pages 147-158
Published: 1986
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSThe time profiles of negative ions formed by X-ray irradiation in nitrous oxide at atmospheric pressure have been measured in the temperature range from 256 K to 500 K by using TRAPI. N2O2(N2O)n- ions (0≤n≤8) and N3O2- ions were observed but N2O(N2O)n- ions were not detected. The rates of negative ion formation were almost invariable for the different ionic species at the same temperature. The formation of the negative ions by thermal electron attachment was interpreted by the following processes; N2O↔N2O* (vibrationally excited in bending mode), eth- + N2O-*↔N2O-*, N2O-* + N2O → N2O2- + N2. The apparent activation energy of these processes was obtained to be 0.21 ±0.04 eV. The value of this activation energy corresponds to the excitation energy of the third vibrational level in the bending mode of N2O. The formation of N2O2- ions has been discussed in terms of the distribution of the cluster size (n) in N2O2(N2O)n- ions and the activation energy which is lower than that of the dissociative resonance electron capture in N2O (e- + N2O → O- + N2).View full abstractDownload PDF (781K) -
Kunio Sasakawa, Masahiko Tsuchiya1986 Volume 34 Issue 3 Pages 159-169
Published: 1986
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSLiquid ionization mass spectrometry was applied to distinguish between several types of fruits wines, such as grape wines (made from grapes), other fruits wines (made from fruits other than grapes) and grape wines with flavors. A microsyringe with a sharpened needle was used as a sample holder (Fig. 1), instead of a simple needle used previously.
Three μl of a sample wine is sucked into the microsyringe and then the syringe is installed in the ion source. One μl of the sample is pushed out to form a droplet on the needle tip and is ionized by metastable argon atoms at atmospheric pressure. When the needle is heated at a heater current of 0.5 A (ca. 40°C), the minor components of wines are observed most abundantly. A mass spectrum between m/z 10 and 400 is scanned in 3 seconds and 30 mass spectra are recorded for 5 minutes. An averaged mass spectrum of 30 scans and a subtracted mass spectrum are printed out by a microcomputor system. Seven characteristic Peaks (G) at m/z 88, 105, 133, 134, 168, 178, 179 to be indicative of grape wines, 6 characteristic peaks (F) at m/z 108, 113, 118, 149, 155, 159 to be indicative of fruit wines, and 5 specific peaks (U) at m/z 214, 228, 238, 246, 253 to be indicative of non-grape property were selected from mass spectra of about 30 bottles of wines. The number of the characteristic (G and F) and specific (U) peaks were counted for each wine and summarized as three dimentional graphic representation (Fig. 6). Results indicate that the method is useful for differentiating these types of wines. The method provides more informations and is simpler and quicker than other analytical methods.View full abstractDownload PDF (677K) -
Kimio Isa, Hideyuki Torii, Toshiaki Kinoshita, Ryuji Nakata, Keiko Miz ...1986 Volume 34 Issue 3 Pages 171-179
Published: 1986
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSThe mass spectra of EDTA salts and complexes were measured by means of FABMS. Three main quasi-molecular ions, (M-A+H+H)+, (M+H)+, and (M+A)+ were detected, in which M and A represent EDTA molecule and alkali metal element, respectively. In the case of EDTA containing only alkali metal element, six characteristic ions {(H5-n AnY)+ n=0 to 5, and Y represents (-OOCCH2)2 NCH2CH2N (CH2COO-)2} were observed. Comparing the intensities of three characteristic ions of EDTA containing alkali earth metal elements (Mg, Ca, and Sr) with (2G+H)+ ion of glycerin, we found that the intensities of characteristic ions were in proportion to the order of the inverse of the ionic radii of the elements. However, in the cases of the EDTA complexes containing transition metal elements, the order of the intensities of characteristic ions are turned out to be as follows,
Mn2+ > Co2+ > Ni2+ > Cu2+ < Zn2+.
In the case of EDTA containing Fe(III), both oxidation and reduction reactions were recognized. Moreover, in the case of non-metal EDTA compound, both (M+H)+ and (M+NH4)+ quasi-molecular ion were detected. In a few EDTA complexes, dimer quasi-molecular ions were also detected.View full abstractDownload PDF (601K) -
Direct TLC/MS Using New Sintered TLC PlateKouji Iwatani, Tetsuro Kadono, Yuzo Nakagawa1986 Volume 34 Issue 3 Pages 181-187
Published: 1986
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSMass spectrometry for nonvolatile and thermally unstable mixture samples still remains as a difficult problem. Thin-layer chromatography (TLC) is a simple and very effective method for the separation of mixtures. For coupling of TLC with mass spectrometry, a new TLC glass plate was devised. The plate has many linear grooves engraved on the rear, which guide a cutter to cleave to a strip. The strip is set on a usual holder for a mass spectrometer. This system provides a very simple and effective result for separation and measurement of mass spectra of the nonvolatile and thermally unstable mixtures.View full abstractDownload PDF (360K) -
Direct TLC/SIMS and Scanning TLC/SIMSKouji Iwatani, Yuzo Nakagawa1986 Volume 34 Issue 3 Pages 189-195
Published: 1986
Released on J-STAGE: May 01, 2007
JOURNAL FREE ACCESSA new technique, direct combination of thin-layer chromatography (TLC) with liquid secondary ion mass spectrometry (SIMS) enables very simple and excellent measuring method for thermally unstable mixture samples such as peptides and drug metabolites. For this technique a small strip of TLC aluminium sheet coated with silica gel taken from the usual developed TLC plate was used as a primary ion target in place of usual silver (metal) plate. In addition to this single spot measuring way, a TLC plate scanning technique was described.View full abstractDownload PDF (337K)
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