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Volume 45, Issue 9
Displaying 1-11 of 11 articles from this issue
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Kensei KOBAYASHI1996 Volume 45 Issue 9 Pages 811-824
Published: September 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSStudies on analyses of bioorganic compounds which were abiotically synthesized in possible primitive planetary environments are reviewed. Life on earth is thought to have its origin about 3.8 billion years ago in primordial sea, using organic compounds dissolved in seawater. Various kinds of experiments have been performed to examine how these organic compounds were abiotically synthesized in simulated primitive terrestrial and/or extraterrestrial environments. Since reaction products of such experiments usually had quite complex matrices, the identification and/or determination of bioorganic compounds in them requires good separation methods and mass spectrometric techniques. Discrimination of the real products from contaminants from laboratory environments is another essential factor in these experiments.
Analyses of extraterrestrial organic compounds are necessary for learning about not only the chemical evolution on other planetary bodies but also the chemical evolution and origin of life on our planet earth, because we have very few chemical fossils before the origin of life here on earth. New techniques and instruments for missions in search of organic compounds on outer planets, comets and Mars are now required.View full abstractDownload PDF (2753K) -
Junko ODA, Syogo ICHIKAWA, Tadashige MORI1996 Volume 45 Issue 9 Pages 825-835
Published: September 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAn analytical method to quantify 30 kinds of polycyclic aromatic hydrocarbons (PAH), including two-to seven-ring ones such as naphthalene to 3, 4, 8, 9-dibenzopyrene, in airborne particulates was studied by capillary gas chromatography/mass spectrometry (GC/MS). Identification of unknown PAH from samples was performed by using their mass spectra and the programmed temperature retention index (PTRI) value of standards. Particulates collected on quartz-fiber filters were extracted with benzene/ethanol (4 : 1) by ultrasonication and their extracts were successively purified on a silicagel column containing 5% -water with 40 ml of 30 % -benzene/hexane. The recoveries of PAHs with molecular weights higher than phenanthrene were over 68 %. Twenty PAH compounds in 22 airborne particulate samples collected from five stations were quantified by GC/MS (SIM). As a result, the five PAH profiles were nearly identical and showed independent differences in concentrations among the sampling stations. Even when GC conditions were different, the PTRI values, which were measured with four types of methyl silicone capillary column, indicated small coefficients of variation, from 0.6 to 1.4% for thirty PAHs. Ninety-two compounds, including two- to seven-ring alkyl-PAHs and sulfurheterocyclics, in an airborne particulate sample were identified from their mass spectras and the standard PTRI values. Therefore, the GC/MS method combined with the PTRI value was useful for determination of PAH in airborne samples.View full abstractDownload PDF (1790K) -
Susumu ICHINOKI, Mitsuru YAMAZAKI, Miyuki OMURA, Rika NAGAI1996 Volume 45 Issue 9 Pages 837-844
Published: September 05, 1996
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSVarious procedures for reversed-phase HPLC determination of Cd, Ni, Pb, Zn, Cu, Hg, Co, and Bi as their hexamethylenedithiocarbamate (HMDC) chelates have been automated. The optimum analytical conditions were investigated for determination of the heavy metals in the standard reference material (Bovine Liver) of National Institute of Standards and Technology (NIST). A 100 mg sample was ashed with nitric and perchloric acid, and the residual acids evaporated. The resulting residue was then dissolved with diluted hydrochloric acid, and an aliquot of the solution was used for the HPLC analysis. The preparation of the standard solutions for calibration curves, chelation of metal ions, on-line enrichment of the HMDC chelates on a Capcell C18 mini-column (10 × 4.0 mm i.d.), separation of the chelates on a Cosmosil 5C18-MS analytical column (250 × 4.6 mm i.d.), and detection at 260 nm were all carried out with an optimum pretreatment program and a time program. The analytical results of Zn and Cu (Zn: 124 ± 2, Cu: 156 ± 3 μg) were in good agreement with the certified values of NIST (Zn: 123 ± 8, Cu: 158 ± 7 μg/g), and the precision of the present method was also good (about 2%).View full abstractDownload PDF (1269K) -
Kunihiro WATANABE, Yukitaka TOMIZAWA, Masayuki ITAGAKI1996 Volume 45 Issue 9 Pages 845-850
Published: September 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe enhancing effect of nonionic surfactant on the fluorescence intensity of Al(III)-Lumogallion complex in aqueous solution has been investigated. In order to examine the enhancement mechanism, the fluorescence properties of Al(III)-Lumogallion complex were measured in nonionic surfactant solution using a fluorescence lifetime instrument. The fluorescence emission rate constant (kf) was not affected by nonionic surfactant. On the other hand, the radiationless transition rate constant (kq) decreased about 1/3 compared with the kq in water. When fluorescence quencher (Q) is present, the fluorescence lifetime (τ) is expressed as τ=1/(kf+knr+k2 [Q]), where knr and k2 refer to the rate constants of the first radiationless transition and the second quenching, respectively, and kq is the sum of knr and k2 [Q]. The fluorescence lifetime of Al(III)- Lumogallion complex was measured in various mixtures of water and methanol. A linear relation was obtained from plots of 1/τ vs. [Q] in methanol by considering the water as a quencher [Q]. As a result, the water is a quencher of Al(III)-Lumogallion complex. The kq in the presence of nonionic surfactant was nearly equal to knr in water, proving that Al(III)-Lumogallion complex was protected by micelle formation from the quencher bulk water. Because the nonionic surfactant micelle separate into the organic phase from the aqueous phase above the cloud point, the surfactant was used as an extraction solvent for Al(III)-Lumogallion complex. When 6% Triton X-100 in 50 ml was used, the surfactant phase volume was 7.6 ml, and the extractability of aluminum was 72%. The detection limit of aluminum by the present method was 0.05 ppb, which is about 4.1 times superior to the conventional method.View full abstractDownload PDF (926K) -
Kunihiro WATANABE, Takashi KOMATSU, Masayuki ITAGAKI1996 Volume 45 Issue 9 Pages 851-857
Published: September 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe conditions of back-extraction factor for higher recoveries of heavy metals from alkaline liquid by the simultaneous forward and back-extraction method need to be considered. In this paper, back-extraction kinetics and the contribution of stirring are discussed. The metal complexes of Cu(II), Mn(II) and Ni(II) with 1-(2-pyridylazo)-2-naphthol (PAN) were investigated. EDTA or HNO3 solution was used as the back-extraction aqueous solvent. The reaction rate increased when interface area increased under highspeed stirring, indicating that interface significantly contributes to the reaction rate. In the present method, the reaction rate, Kobs, was divided into that in the bulk and at the interface. Rate constants for the ligand substitution reaction of Cu(II)-PAN and Mn(II)-PAN complex with EDTA in the bulk were determined to be 3.7 × 103 and 5.2 M-1 s-1, respectively. Rate constants for the dissociation reaction of Cu(II)-PAN, Mn(II)-PAN and Ni(II)-PAN complex in bulk were determined to be 4.5 × 102, 5.2 × 103 and 2.9 × 10_-1 M-1 s-1, respectively. The contribution of interface was more significant with HNO3 solution than with EDTA solution.View full abstractDownload PDF (1088K) -
Jun-ichi ITOH, Masashi KOMATA, Yoshihiro KONDOU1996 Volume 45 Issue 9 Pages 859-863
Published: September 05, 1996
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSA new highly effective preconcentration method for Cu(II), Ni(II), Co(II) and Cd(II) in water samples which involves the filtration of these metal ions combined with pulverized Chelex 100 resin using a micro-membrane filter (MMF, cellulose nitrate, diameter: 4 mm, pore size: 1.00 μm) was developed. It was possible to determine these metal ions collected on the MMF by graphite furnace AAS in which the MMF was introduced directly into a cup type graphite cuvette. Over 93% of these metal ions were recovered by the MMF at pH 4.5 for Cu(II) and at pH 6.5 for other metal ions. Only a 5 ml sample of the metal ion at less than ppb-level was enough for one analysis. The detection limits (3σ of blank solution) for Cu(II), Ni(II), Co(II) and Cd(II) are 45, 95, 30 and 0.95 ppt, respectively. An application of the method for Cu(II), Ni(II) and Cd(II) in seawater was also described.View full abstractDownload PDF (686K) -
Toshimitsu OKAMOTO, Akinori ISOZAKI, Hisomu NAGASHIMA1996 Volume 45 Issue 9 Pages 865-871
Published: September 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA method for the determination of chloride, bromide and sulfate in color additives used in drugs and cosmetics (D&C colors) by ion chromatography on a ceramic carbon column was developed; the method was applied to the determination of chloride, bromide and sulfate in D&C colors both by the direct injection method and by an oxygen-flaskcombustion method. In the direct injection method, 50 mg of a sample was dissolved in 500 ml of water which was then passed through a Toyopak IC-SP cartridge. In the oxygen-flask-combustion method, several mg of a sample were burned in an oxygen-filled flask containing 20 ml of 2 mM NaOH and 100 μl of 5% NH2NH2 for determination of bromine, 20 ml of 2 mM NaOH, and 100 μl of 1% H2O2 as an absorbent for determination of sulfur, and water added to make 100 ml. A 20-μl aliquot of each sample solution was injected into a ceramic carbon column and eluted with 5% acetonitrile containing 2 mM Na2CO3 and 1 mM tetrabutylammonium hydroxide, under the following operating conditions : flow rate, 0.8 ml/min; column temperature, 40°C; scavenger, 12.5 mM H2SO4. The content of chloride, bromide and sulfate in D&C colors by the direct injection method was found to be lower than 4.3, 1.4 and 0.4%, respectively. The amount of dye molecules determined from total bromine or total sulfur by the oxygen-flask-combustion method was in good agreement with that determined by the titration method or the gravimetric method as directed in The Japanese Standard of Cosmetic Ingredients.View full abstractDownload PDF (1085K) -
Shuyo YAMAMOTO, Hideyuki MATSUTA, Kichinosuke HIROKAWA1996 Volume 45 Issue 9 Pages 873-877
Published: September 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSMeasurements of the electron beam induced X-ray excited photoelectrons were performed using an Auger electron spectrometer ( JEOL JAMP-7100E). When a focused electron beam is irradiated through a thin film evaporated on a substrate, the electron beam penetrates the substrate and produces characteristic X-rays to induce photoelectrons from elements in the thin film. Differentiated photoelectron spectra of Ag3d, Au4f, Bi4d, Bi4f, Cls, Mn2p, Pb4d, Pb4f and Sn3d from thin films of these elements on the Al substrate were obtained. We applied the conventional equation of XPS intensity to the intensity of electron beam induced X-ray excited photoelectrons. Quantitative analysis of Au-Ag alloys was performed by this method and the results were in good agreement with those obtained by Auger spectroscopy with the relative sensitivity factor method. When an oxidized Cu film on the magnesium substrate was measured by this method, chemical shifts and satellite peaks of the photoelectron peak that are characteristic of Cu(II) can be detected. Lateral resolution of line analysis with this method was found to be much better than that with the conventional XPS spectrometer.View full abstractDownload PDF (771K) -
S. MORI, S. TAKAYAMA, Y. GOTO, M. NAGATA, A. KINUGAWA, T. HOUSAKI, M. ...1996 Volume 45 Issue 9 Pages 879-885
Published: September 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAt 2nd round robin test (RR-2), the problem on the baseline construction was considered to be the main reason of high relative standard deviations (RSD) of number-average molecular weight (Mn). There are two methods to construct baseline of an SEC chromatogram. Method A is the extrapolation from the baseline at the beginning of the polymer chromatogram to the baseline after the solvent related peaks and method B is the draw of a linear baseline between the beginning of the polymer chromatogram and the end of the chromatogram before the solvent related peaks (the lowest point between them). Laboratories at RR-2 were divided into two groups, group A which employed method A and group B which employed method B. After evaluating all data of Mn and removing invalid data, RSDs of Mn were calculated separately. RSDs in group A were between 5.2 and 7.1 % and those in group B was between 7.3 and 9.3 %. The average values of Mn in group B were 1.13 to 1.23 times higher than those in group A. It is essential to standardize the procedure of the baseline construction in order to obtain better RSD. Ideally, method A is preferable, but there were several invalid data due to the disturbance of solvent related peaks and the low setup of cutoff molecular weight which must be between 2500 and 3000. Method B is more appropriate, but tends to neglect low molecular weight components.View full abstractDownload PDF (958K) -
Shigeyuki MORI, Katsuhiko AKASAKI, Yoshiro MATSUMOTO1996 Volume 45 Issue 9 Pages 887-893
Published: September 05, 1996
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSIn order to support the development of beta titanium alloys that have no commercial standard materials, the applicability of x-ray fluorescence analysis combined with the fundamental parameter (FP) method was investigated. By using the FP method characteristic in calculating the instrumental sensitivity for each analytical line when converting the measured intensity into the theoretical one, the rule of thumb for selecting the appropriate standard materials from those available was sought. As a result of using one of α or β+β titanium alloy standard materials with concentration ratios of standard to unknown of 0.4-9 for the alloying elements and of 0.4-2000 for the impurities, the composition of the β titanium alloys, Ti-10V-2Fe-3Al and so called Ti-17, were analyzed with a relative error of ± 7% for the alloying elements and of ± 13% for the impurities.View full abstractDownload PDF (3040K) -
Shiquan TAO1996 Volume 45 Issue 9 Pages 895-896
Published: September 05, 1996
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSNovel methods for sample introduction in inductively coupled plasma atomic emission spectrometry were developed by combining chemical reactions and low-temperature electrothermal vaporization. Analytes in samples of complex matrices were transformed to volatile compounds through in situ alkylations or chelating reactions and vaporized successively at comparatively low temperatures into the plasma. Since both the formed alkylmetals and the alkylating agents used in this work are sensitive to water and air, reaction systems which are free from water and air were established. By these approaches, introduction efficiency of nearly 100% was achieved for all the elements examined. Moreover, since the formation and vaporization of the volatile species were carried out at temperatures lower than the melting points of most inorganic materials, most coexisting metal ions did not interfere with the determinations. Analytical results for beryllium, cadmium, chromium, vanadium and zinc in various standard reference samples by the proposed methods certified the validity of these methods in practical applications.View full abstractDownload PDF (319K)
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