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Volume 47 (1999)
- Issue 6 Pages 319-
- Issue 5 Pages 289-
- Issue 4 Pages 251-
- Issue 3 Pages 97-
- Issue 2 Pages 67-
- Issue 1 Pages 2-
Volume 47, Issue 6
Displaying 1-16 of 16 articles from this issue
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REVIEWS
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Haruyuki KANEHIRO1999 Volume 47 Issue 6 Pages 319-321
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSThe distribution and abundance of plastic litter, especially resin pellets, were investigated. Resin pellets are widespread in the coastal waters and beaches of Japan. Such pellets that are the raw materials of plastic products are important marine pollutants for many species of marine life such as ingestion by seabirds and fishes. In this report, organic pollutants in resin pellets collected from beaches and coastal waters were analyzed. NP (nonylphenol), PCB (polychlorinated biphenyls), and DDE (dichlorodiphenyldichloroethylene) were identified by GC/MS measurement. Their concentrations in 1 g of pellet sample (polypropylene and polyethylene) were as follows: NP (130-25,000 ng), PCB (5-120 ng), and DDE (0.2-3.1 ng). GC/MS analysis of resin pellets suggests that these pollutants were derived from the ambient seawater.View full abstractDownload PDF (291K) -
Takashi NOHMI, Maya MAEKAWA, Hiroyuki HATANO1999 Volume 47 Issue 6 Pages 322-328
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSRecently, distribution map of poisonous chemicals from combustion process fires into troposphere has been analyzed. Air and ground pollution is monitored at the area by sampling. The concentration of the contaminated matter is detected and the environmental pollution problems come to the surface. It is necessary to measure the concentration of contaminant continuously, explore the origin of pollution, stop the diffusion of pollution, separate the pollution from residential area and treat the contaminated matter to detoxify. This report introduces Spectro Telescopy, Mass Spectrometry, and Electron Spin Resonance Spectroscopy to monitor the trace contaminated matter in the troposphere.View full abstractDownload PDF (814K) -
Takashi NOHMI, Yoshio KOBAYASHI1999 Volume 47 Issue 6 Pages 329-339
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSFire is a kind of plasma. This report explains the relationship between ions and fire. Also trends and cause of fire are studied. Recently scientific analysis have been introduced to fire research in order to distinguish fire from arson. Examples of fire analysis and ionization fire detector are also explained.View full abstractDownload PDF (1142K) -
Kunihiko TAKEDA1999 Volume 47 Issue 6 Pages 340-348
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSLast year, about 2,000 lives were claimed by fires, and like other developed countries, this number has gradually been increasing in the 1990s. Both the government and industry have been forced to take measures to reduce fires. Many sophisticated technologies to prevent fires have been developed and put to use, but no definitive and effective method that fits the requirements of flame retardancy and also overcomes environmental problems has been found. Several representative methods for flame retardancy will be summarized in this paper, and will be followed by the description of thermal degradation processes and the analysis of combustion products from plastics with mass spectroscopy that will take a leading part in the future.View full abstractDownload PDF (1152K)
COMMENTARY
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Takeo OZAWA1999 Volume 47 Issue 6 Pages 349-353
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSTwo remarkable trends of diversification have been recently observed in thermal analysis, and they are those in techniques and heating modes. Evolved gas analysis (EGA) with a mass spectrometer (MS) is one example of diversification in techniques. In conventional thermal analysis, such as DTA, DSC, and TG, it was implicitly thought before that the sample is heated at a constant heating rate, but controlled rate thermal analysis, temperature modulation technique, temperature jump method, and rate jump method have recently been utilized as new heating modes. Usefulness of these new heating modes are illustrated with applications of thermogravimetry, EGA(MS) and their simultaneous measurement to polymers and inorganic substances. New facts were found by combined use of various heating modes. Versatility of these new techniques and new heating modes is also shown in their potential applicability to new tasks, i.e., complex reactions, such as competitive parallel reactions and consecutive reactions.View full abstractDownload PDF (535K)
REGULAR PAPERS
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Tadashi ARII, Yutaka SAWADA, Nobuo KIEDA, Shigeyuki SEKI1999 Volume 47 Issue 6 Pages 354-359
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSAmmonium oxalate monohydrate (NH4)2C2O4·H2O was investigated by TG-DTA-MS and controlled-rate TG. The decomposition process in both inert and simulated air atmospheres was successfully clarified; the gaseous products evolved with three endothermic mass losses were confirmed by the mass detection. Detection of ammonia from the dehydrate (NH4)2C2O4 supported the formation of ammonium hydrogen oxalate (NH4)HC2O4 which decomposed at the higher temperature to form ammonia, water vapor, carbon monoxide and carbon dioxide. The successive mass losses were clearly separated and characterized by controlled-rate thermogravimetry, CRTG. The well-defined mass loss curve brought by CRTG agreed excellently with the theoretical mass losses calculated based upon formation of anhydrous ammonium oxalate and ammonium hydrogen oxalate, respectively. The gaseous products detected under the thermo-oxidative decomposition were attributed to the oxidized products for those obtained under the inert atmosphere. Thermal change in the oxidation atmosphere accompanied nitrogen monoxide NO, extra formation of water vapor and carbon dioxide. The decomposition mechanism was little affected by the atmospheric differences. The decomposition mechanism of (NH4)2C2O4·H2O was proposed.View full abstractDownload PDF (625K) -
Yuichi ISHIZUKA, Toshihide NISHIMURA1999 Volume 47 Issue 6 Pages 360-363
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSA cryogenic gas chromatography/mass spectrometry (GC/MS) was developed for the head space analysis of a reconstituted Dalacin P for Injection® containing clindamycin phosphate as the active entity, and this method improved retention time separation near mercaptan and enhanced detection sensitivity. A reconstituted Dalacin P® smells like a “rotten cabbage”. The cryo-GC/MS method found that ca. 100 ppm of methyl mercaptan and ca. 600 ppm of dimethyl disulfide are mainly produced as offensive materials. Contrary to this, in the headspace of the Dalacin S for Injection® (the new formulation) contained both materials less than 3 ppm.View full abstractDownload PDF (323K) -
Tetsuo HIGUCHI, Chuichi WATANABE, Ikuo SAKAI1999 Volume 47 Issue 6 Pages 364-370
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSChemical hazardous materials in the pyrolysate of polyvinyl chloride have been identified using a new tandem pyrolyzer combined with a capillary GC/MS. On this study, polyvinyl chloride was pyrolyzed in a first micro furnace maintained at 600°C in helium, and then pyrolyzates were introduced again into a second micro furnace in order to obtain the further information in air circumstances. As a result, aromatic compounds, acids and aldehydes, in addition to a trace level of chlorinated aromatics such as pentachlorophenol which is one of precursor compounds of dioxine was detected. The tandem pyrolysis GC/MS system presented is very powerful analytical tool to characterize the pyrolyzate of polymers in different circumstances.View full abstractDownload PDF (600K) -
Relation between Thermal Decomposition Behavior and Ceiling TemperatureJian Ping CHEN, Kimio ISA, Toshiyuki KODAIRA, Tetsuya SENDA1999 Volume 47 Issue 6 Pages 371-381
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSThe thermal decomposition behaviors of polystyrene, its derivatives, and polyolefins were investigated by thermogravimetric method in which gas chromatography and/or mass spectrometry are interfaced. Decomposition products of polystyrene and poly(p-methyl styrene) were found to be predominantly monomers with a few dimers. In the case of the poly(α-methyl styrene), the monomer was observed as the predominant species and the amounts of other products were quite negligible. As for the formation ratio of dimer to monomer, the observed ratios for polystyrene and poly(p-methyl styrene) were all less than those reported in the literatures obtained by isothermal method. Dimers were detected only in a high temperature range, where the mass loss was seldom to occur. Since the formations of the most of dimers are considered to occur at the completion of the decomposition reactions, the most of dimers are produced from secondary reactions in the case of polystyrene and its derivatives. The decomposition products of polyolefins were mixtures of hydrocarbons. Especially, the major decomposition products of polyethylene were hydrocarbons of C10-C14, and the monomer was not observed. From considering the molecular structures of cyclic products, it was seen that the secondary reaction(s) occurred to form the complicated final products in the case of polypropylene. The relation between the decomposition temperature of polymers and the ceiling temperature of their monomers was noted. In case that the thermal decomposition temperature range is above the ceiling temperature, a lot of monomer is produced, while if it is below the ceiling temperature, the monomer is rarely observed.View full abstractDownload PDF (842K)
COMMUNICATIONS
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Kenzo HIRAOKA, Tetsuya SATO, Toshikazu TAKAYAMA1999 Volume 47 Issue 6 Pages 382-385
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSCometary nuclei are the least modified solar system bodies remaining from the time of planetary formation. Their current compositions are thought to be representative of the materials from which they formed. In the observation of comets Hyakutake1) and Hale-Bopp, C2H4 has not been detected by infrared spectroscopy despite of the strong intensities of C2 hydrocarbons, C2H2 and C2H6. In the present work, the reaction of H atoms with solid thin film of C2H2 at 10 K has been studied by means of thermal desorption mass spectrometry and FT-IR spectroscopy in order to obtain information on the chemical evolution on the cold dust grains. It was found that C2H6 is only the major product and the intermediate C2H4 could not be detected. This finding is in accord with the failure of the observation of C2H4 in the coma of the comets Hyakutake and Hale-Bopp.View full abstractDownload PDF (322K) -
Jun FUTAMI, Hiroaki IRIE, Shuzo OHE, Isao NISHI1999 Volume 47 Issue 6 Pages 386-388
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSIn recent studies, it has been revealed that Helicobacter pylori (HP) causes stomach cancer, stomach ulcers, duodenal ulcers and chronic gastritis. The 13C-urea breath test (UBT) is one of the diagnostic methods for HP infection. A new UBT method with the respiratory mass spectrometer developed by authors continuously measures with on-line the amount of decomposed 13C-urea in the stomach after the administration of 13C-urea. Trial examinations by the new method were carried out with two subjects; one was diagnosed positive of HP infection and the other was negative by clinical examinations. Significant difference was found in the amount of decomposed 13C-urea between both subjects. The results presented in this paper demonstrate that the new UBT method is applicable to the clinical use in the diagnosis of HP infection.View full abstractDownload PDF (275K) -
Toyofumi NAKANISHI, Akira SHIMIZU1999 Volume 47 Issue 6 Pages 389-391
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSLiquid chromatography-electrospray ionization mass spectrometry (LC-ESIMS) was used to measure the ratio of the ion peak intensity of the glycated and non-glycated hexapeptides from the amino terminal of hemoglobin (Hb) β-chain to establish an accurate method of measuring glycated hemoglobin (HbA1c). Chemically synthesized glycated and non-glycated hexapeptides were mixed in various ratios, and the mixtures were analyzed by on-line reverse phase LC connected to ESIMS. We found that the ratio of the peak intensity calculated by the equation, 0.5 × peak area of doubly charged ion + 1 × peak area of singly charged ion for each peptide was the most reproducible. The slope of the resulting curves from the equation was nearly equal to 1. This calculation should improve the accuracy of the reference method for HbA1c, proposed by Kobold et al., based on LC/ESIMS analysis of the specific N-terminal residues of the Hb β-chains, which are released by enzymatic cleavage of the intact Hb molecule with endoproteinase Glu-C. The measurement of HbA1c both by the MS method proposed in the present paper and by a conventional HPLC method revealed that the values obtained by HPLC were ca. 20% higher than those obtained by MS.View full abstractDownload PDF (268K)
READERS PLAZA “NEW FACE”
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Keiichiro ISHIKAWA1999 Volume 47 Issue 6 Pages 397-400
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSAcetylation of the amino-groups of HIV-p24 proteins with normal acetic anhydride and deuterated acetic anhydride followed by the mass spectrometric peptide mapping was carried out for the evaluation of relative reactivities of lysine residues at varying locations. The mild acetylation by normal acetic anhydride giving partially acetylated (h-Ac) lysine residues was followed by the complete deuteroacetylation to label the unreacted lysine residues with trideuteroacetic groups (d-Ac). The relative reactivities of lysine residues were evaluated based on the ratios of h-Ac/d-Ac observed by electrospray ionization mass spectrometry of unfractionated tryptic digests of acetylated p24. The relative reactivities of four lysine residues (K158>K170≥K 140>K25) showed a correlation with their solvent accessibilities (SA) derived from the tertiary structure of HIV-p24 predicted by computer modeling and X-rar crystallographic analyses. It is shown that the combination of selective chemical modification and mass spectrometric peptide mapping of proteins is useful to probe their tertiary structures derived from X-ray crystallography or NMR spectroscopy.View full abstractDownload PDF (424K) -
Maya MAEKAWA1999 Volume 47 Issue 6 Pages 401-404
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSHistorically, a lot of disaters by fire have destroyed lives and properties. And fire detection system especially in the early stage has been explored. Monitoring the smog concentration and the temperature in the room are the typical method for fire detection. Nowadays influence upon the environment by the thermal decomposition products of fire becomes more important because of dioxin, PCB (polychlorobiphenyl) and their toxicity. Also new chemical species have been found in the thermal decomposition products by the development of the analytical instruments, for example, gas chromatography mass spectrometry and odor sensor. Pyrolysis mechanism of cellulose and its roasted odor were studied by odor sensor, GC-MS and TG-MS. The roasted odor was generated from 170°C when cellulose was heated and pyrolized. Odor sensor made of tin oxide semiconductor thin film detected the odor products at 170°C, which was almost the same temperature that a human nose could detect. The human and the artificial nose could be understood to sense the same evolved gas among the decomposition products. We analyzed the decomposition products of cellulose and found levoglucosan as a main product around 300-400°C by GC-MS under He condition. TG-MS study was carried out under air condition and levoglucosan was detected. Levoglucosan (mp 182°C, bp 280°C) was estimated to sublimate over the temperature of 200°C. When cellulose pyrolized, the chemical weak bonding of -O- was scissored randomly. Finally this scission stopped when it created the monomer unit of cellulose, that is levoglucosan. Considering these facts we concluded the roasted odor by the decomposition of cellulose must be levoglucosan.View full abstractDownload PDF (405K) -
A Sonic Spray Interface for Capillary Electrophoresis/Mass SpectrometryYukiko HIRABAYASHI1999 Volume 47 Issue 6 Pages 405-408
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSAn interface for capillary electrophoresis/mass spectrometry (CE/MS) using sonic spray ionization (SSI) was developed. In the SSI technique, a sample solution is sprayed at any solution-flow rate from a sample-introduction capillary with a high-speed gas flow coaxial to the capillary and ions are formed at atmospheric pressure. Therefore, it can be used with a wide range of buffer solutions regardless of the conductivity of the solutions. SSI is now being used as an interface in semi-micro and conventional liquid chromatography/mass spectrometry (LC/MS). However, the pressure around the tip of the sample-introduction capillary is reduced by the high-speed gas flow, so the solution is pumped into the capillary at a flow rate above 0.1 μL/min due to the difference of pressure between the two ends of the capillary. Since the solution-flow rate in CE is much lower than this pumping rate, the resolution of CE separation is expected to be decreased by the pumping effect when an electrophoresis capillary is connected directly with the sample-introduction capillary. To prevent this in CE/MS, the author has set a buffer reservoir between the sample-injection capillary and the electrophoresis capillary. Using this interface, the author has demonstrated CE/MS analysis with a mobile-phase buffer containing 15 mM of phosphate by filling the buffer reservoir with an acetic-acid solution as a substitute for the mobile-phase buffer. This increased the ion intensity 100-fold by enhancing the evaporation of charged droplets produced by the spray.View full abstractDownload PDF (394K) -
Sadamu KURONO1999 Volume 47 Issue 6 Pages 409-414
Published: 1999
Released on J-STAGE: October 16, 2007
JOURNAL FREE ACCESSChemically synthesized chondrotin di-, tri-, and tetrasaccharides having 4-, 6-mono and 4, 6-disulfates were analyzed by mass spectrometry (MS). The MS analytical method for a slight amount of glycoconjugate was efficient to confirm its structure standing on the different point from NMR method. The sequences of these sulfated chondroitin oligosaccharides, especially the linkage position of the sulfate group, were confirmed by the measurement of the CID-MS/MS. Thus, the CID-MS/MS could distinguish between the 4- and 6-sulfated position on the galactosamine residue by the different fragmentation patterns from the desodiated ion of the common part, disaccharide GalNAcβ1→4G1cA, as a precursor ion. In this report, we demonstrate the possibility of the detection of the binding site of the sulfate group on some kinds of saccharides or glycoconjugates, as a result, we can make structural distinctions between sulfated linkage isomers or sulfated positional isomers using MS.View full abstractDownload PDF (472K)
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