巻号一覧
44 巻 (1996)
- 6 号 p. 563-
- 5 号 p. 501-
- 4 号 p. 461-
- 3 号 p. 293-
- 2 号 p. 105-
- 1 号 p. 1-
44 巻, 2 号
選択された号の論文の15件中1～15を表示しています
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総説
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能美 隆1996 年 44 巻 2 号 p. 105-122
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーScientist observed natural phenomena and found the existence of ions more than 100 years ago. When the historical background of electrospray was surveyed from the view point of the ionization technique, the origin started by the awareness of the charged drops in nature. Our earth is positively charged and abounds in the positive ion. Iribarne noticed that ions were produced by bubbles at the surface of sea water forming the electric double layer and utilized these fact to create ions. Dole ionized polymers by the hydrostatic electrification of droplets from the hypodermic needle with the Faraday cage as a function of the repeller voltage and originated the electrospray ionization. Cluster ions were separated by the skimmer technique and the positive and the negative ion peaks were obtained. The multiply charged macroion from electrospray ionization was determined. Now electrospray ionization of liquids with quadrupole mass analysis to analyze proteins and nucleotides is one of the main streams of the structural characterization.抄録全体を表示PDF形式でダウンロード (1539K) -
田中 健一郎, 関谷 徹司1996 年 44 巻 2 号 p. 123-132
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーPhotochemical reactions following core electron excitation on solid surfaces have been subject of intense research. Among such surface reactions, photon stimulated ion desorption (PSID) is a relatively simple and important process to investigate reaction dynamics both theoretically and experimentally.
Recently, we have studied PSID from small molecules on Si(100) surface and from polymer thin films using time-of-flight mass spectrometric techniques and observed sitespecific and state-specific chemical reactions. Experimental results for H2O/Si(100), DCOOD/Si(100) and poly(methyl methacrylate) (PMMA) thin films are discussed in terms of primary excitations followed by the Auger decay and the delocalization of the excitation.抄録全体を表示PDF形式でダウンロード (696K) -
―イオン–ニュートラルコンプレックス―田島 進, 関口 治1996 年 44 巻 2 号 p. 133-155
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーPDF形式でダウンロード (1451K)
報文
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Positive Ionization Based Negative Ion FormationMasao INOUE1996 年 44 巻 2 号 p. 157-164
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーDue to the unpaired electron the radical can capture a free electron in its singly-occupied orbital and become a negative ion. In gases irradiated by ionizing radiation radicals are formed by various processes such as dissociation of excited molecules and ions, ion-molecule reactions, and recombination of ions. We wish to introduce our ion cyclotron resonance (ICR) spetrometric study of CN- ion produced in hydrogen cyanide and to demonstrate that the radical CN· formed from the positive ions are the important precursors of CN- ions observed.抄録全体を表示PDF形式でダウンロード (548K) -
Yasuhiro MITSUI, Tadahiro OHMI, Atsushi OHKI, Shigeki HAYASHI1996 年 44 巻 2 号 p. 165-174
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーSemiconductor fabrication field requires screening technology, for external air leakage inspection in a clean room gas delivery system which can inspect all inspection points in one gas line in one process. Recent advances in welding technology have meant that the occurrence of a leak at welding point is now extremely uncommon. Inspection costs of a gas delivery system can therefore be decreased by applying such a screening process. The detection sensitivity required for screening of the air component is ppt level or below.
The atmospheric pressure ionization mass spectrometer (APIMS) was applied to the screening process using the argon carrier gas. Trace nitrogen which previously could not be detected by the APIMS, could be detected by mixing hydrogen in the argon gas. The detection sensitivity was increased over 100 times compared to the oxygen detection since there is a large amount of nitrogen in air and the proton transfer reaction for nitrogen ionization having a larger rate constant than the charge transfer reaction for oxygen ionization. N2H+ intensity shows a sudden increase with H2 concentration because the rate constant, in the rate-determining step for N2H+ formation in higher H2 concentrations, is larger than that in the lower H2 concentrations. The optimum H2 concentration is 3-10% for obtaining the higher sensitivity.
It is expected that the application of APIMS technique will greatly reduce the costs associated with the leak inspection.抄録全体を表示PDF形式でダウンロード (616K) -
Tatsuki MATSUNO, Takashi HIRANO, Mamoru OHASHI1996 年 44 巻 2 号 p. 175-181
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーLiquid secondary ionization mass spectra (LSIMS) of methylsulfate salts of phenyl, isopropyl, and methyl 10-methyl-acridinium-9-carboxylate were examined under chemiluminescent conditions. Under chemiluminescence conditions, oxygenated acrydinium ions [M + 16]+ were observed, whose structures were elucidated as 9-oxy derivatives on the basis of their fragmentation processes obtained by linked scanning at constant B/E. The oxygenated ions are probably derived from the mass spectrometric reaction of the hydroperoxy intermediates in the chemiluminescence proposed by McCapra.抄録全体を表示PDF形式でダウンロード (340K) -
Tadashi II, Yoko OHASHI, Tomoya OGAWA, Yoshitaka NAGAI1996 年 44 巻 2 号 p. 183-195
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーPositive-ion fast atom bombardment (FAB) and electrospray ionization (ESI) mass spectrometry have been used in the structural characterization of sulfated and sialyl Lewis (Le)-type glycosphingolipids. Both FAB and ESI collision-induced dissociation tandem mass spectrometry (CID-MS/MS) of acidic glycosphingolipids allowed identification of the sulfated and sialyl sugars, and provided information on the sugar chain sequences. The positive-ion tandem FABMS of sulfated Le-type glycosphingolipids gave the daughter ions produced by the elimination of (fucose-H2O) unit from the fragment ions containing the non-reducing end. On the other hand, the CID-MS/MS of sialyl analogs showed the characteristic ions derived from the loss of (N-acetylneuraminic acid-H2O) unit, in addition to the elimination of (fucose-H2O) unit. The ESI CID-MS/MS of multiple-charged ions provided even more detailed structural information, and some of the daughter ions useful for structural studies appeared in the higher mass region than the precursor owing to a lower charge-state. These methodologies can be applied to the structural analyses of glycoconjugates with much larger molecular masses and higher polarity, such as the poly-sulfated and sialyl analogs.抄録全体を表示PDF形式でダウンロード (753K) -
Kimio ISA, Kenichi WATANABE, Hiroyoshi KATAOKA, Kaori HIRAI, Ryuji NAK ...1996 年 44 巻 2 号 p. 197-209
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーThe FAB mass spectra of the mixtures of the sulfuric acid and 14 solvent molecules (acetone, methyl alcohol, ethyl alcohol, 1-propyl alcohol, 2-propyl alcohol, 1-butyl alcohol, 2-butyl alcohol, t-butyl alcohol, 1-pentyl alcohol, 1-hexyl alcohol, ethylene glycol, acetic acid, dimethyl sulfoxide, and water) were measured and CAD spectra of the cluster ions were also measured.
The FAB mass spectra showed the extensive cluster ions of H2SO4 with the solvent, (aH2SO4+bSolv+H)+, a and b are positive integers or zero. We also tried to investigate CAD spectra of unsymmetrical protonated ions of sulfuric acid and water molecules, (H2SO4+H2O+H)+, precisely.
The mass spectra were found to be dehydrated ions, (aH2SO4+bSolv-H2O+H)+. In some cases, we determined which dehydration occurred from H2SO4 site or from solvent site. For that problem to be solved, the CAD spectra by means of MS/MS (mass spectrometry/mass spectrometry, tandem mass spectrometry) of (aH2SO4+bSolv+H)+ and (aH2SO4+bSolv-H2O+H)+, were needed to measure. Further the special cluster ions (CnH2n+1OH-H2O+H)+, if proton resides on the larger PA site, the dehydration occurs on the protonated site. We can decide the dehydration site by the present methods.抄録全体を表示PDF形式でダウンロード (722K) -
Osamu SEKIGUCHI, Susumu TAJIMA1996 年 44 巻 2 号 p. 211-218
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーThe unimolecular decomposition of the molecular ions of methyl thiolactate (1) and ethyl thiolactate (2) upon electron impact was investigated. The metastable fragmentation of 1+· is dominated by the loss of methanol. The molecular ions 2+· decompose in a variety of ways: the loss of water, the loss of ethylene, as well as the loss of ethanol are prominent. Both methyl and ethyl thiolactates do not show the fragmentation with double hydrogen transfer, which is observed in methyl lactate (3) and ethyl lactate (4).抄録全体を表示PDF形式でダウンロード (438K) -
Tetsuya SATO, Tohru KINUGAWA, Tatsuo ARIKAWA1996 年 44 巻 2 号 p. 219-227
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーA time-resolved study of nonsteady characteristics in a pulsed nozzle beam whose width is less than 50 μs was carried out. The velocity distributions in pulsed molecular beams were investigated by means of “TOF-metastable spectroscopy” with a high time-resolution, e.g., 0.5 μs. The variations of the relative intensity and speed ratio within the pulse duration were determined. Both of the measured quantities reached maxima near the center of the pulse where the narrowest velocity distribution was obtained. At this position a typical speed ratios were 28 for He, 36 for Ne, and 38 for Ar, and corresponding stream temperatures were 1.2 K, 0.8 K, and 0.8 K, respectively. These values were almost the same as those obtained by a continuous nozzle source with an equivalent nozzle design.抄録全体を表示PDF形式でダウンロード (580K) -
Hisayuki YAZAWA, Ryoichi SHISHIDO, Takashi NOZAWA, Tatsuo ARIKAWA1996 年 44 巻 2 号 p. 229-236
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーFormation of van der Waals clusters of amino-acid tryptophan was investigated by means of seeded supersonic expansion combining with laser desorption technique. Stable van der Waals clusters of tryptophan molecules, (Trp)n up to n=5, were observed in a time-of-flight mass spectrum. No significant difference was observed in the formation of clusters for each enantiomer, i.e., L-, D-, and racemic-tryptophans. Strikingly no dominant van der Waals complexes other than the type of (Trp)n were observed, though weakly bound van der Waals complexes such as a tryptophan·(rare gas)n type are commonly seen in an ordinary seeded beam expansion. The dynamical properties of tryptophan dimers, and trimers in a carrier argon gas were measured by the use of a fast optical imaging device.抄録全体を表示PDF形式でダウンロード (571K) -
Yasuhide NAITO, Ying YAN, Masao INOUE1996 年 44 巻 2 号 p. 237-247
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーThis paper proposes an iterative method of frequency tuning for the burst (fixed frequency rectangular pulse) excitation in FT-ICR spectrometry. Computer simulation of FT-ICR experiment using this excitation method was performed to examine the experimental conditions which converge the excitation frequencies in iteration. Experiment utilizing an FT-ICR spectrometer was carried out to determine the isotope abundance ratio of xenon ions. These results have demonstrated that the method improves appreciably the quantitative performance of FT-ICR spectrometers.抄録全体を表示PDF形式でダウンロード (776K) -
Teruhiko HAGIWARA, Motohiro NISHIJIMA, Sukeji SUZUKI1996 年 44 巻 2 号 p. 249-259
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーIn order to obtain good measurement repeatability for the high performance liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (LC/APCIMS), the peak portion of an analyte eluted from LC was introduced into the interface by using an auto switching valve. This considerably reduced stains tuck to the interface, so that LC/APCI-MS was able to operate stably, and the repeatability was improved. This sample introducing method was applied to the selected ion monitoring (SIM) determination for 3-tert-butyl-4-hydroxyanisole (BHA) and 3,5-di-tert-butyl-4-hydroxytoluene (BHT) contained in dried sardines. The measurement repeatability for BHA and BHT were 2-3% as relative standard deviations. The results were compared with those obtained by the capillary gas chromatography (CGC) of the same sample solution, showing that the quantitative analysis can be performed by LC/APCI-MS with a high repeatability comparable to the CGC.抄録全体を表示PDF形式でダウンロード (607K)
ノート
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Yasuo SHIDA, Motoko FUKUZAWA, Keiko YAMAMOTO, Koji O'HARA1996 年 44 巻 2 号 p. 261-267
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーTwo macrolide antibiotics, clarithromycin and roxithromycin, have recently entered the market and are now in frequent clinical use. These antibiotics were inactivated by an inactivating enzyme, macrolide 2′-phosphotransferase [MPH(2′)I], extracted from highly erythromycin-resistant Escherichia coli, and the reaction products were analyzed by ESI-MS. It was demonstrated that the 2′-phosphate derivatives of these macrolides could be detected by analysis of the mixture of MPH(2′)I and adenosine 5′-triphosphate after only a simple sample pretreatment with the addition of 3% acetic acid into water-methanol (1 : 1, v/v).抄録全体を表示PDF形式でダウンロード (282K) -
Satoko AKASHI, Mikako SHIROUZU, Shigeyuki YOKOYAMA, Koji TAKIO1996 年 44 巻 2 号 p. 269-277
発行日: 1996年
公開日: 2007/07/20
ジャーナル フリーA detection of non-covalent complexes of Ras·GDP and Ras·GppNp (guanosine-5′-(β,γ-imido)-triphosphate; GTP analogue) using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOFMS) is reported. The Ras proteins are bound to GDP or GppNp, non-covalently, with ionic bonds. The GDP-bound Ras is inactive, while the GTP-bound Ras is active. This paper shows the possibility of the detection of the active and inactive form of a regulatory protein, which is non-covalently bound with a nucleotide, with a small sample amount by MALDI-TOFMS analyses. It was also suggested that MALDI-TOFMS is promising for the estimation of the ratio of nucleotide bound Ras protein and free apo-Ras protein.抄録全体を表示PDF形式でダウンロード (658K)
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