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Volume 51, Issue 11
Displaying 1-12 of 12 articles from this issue
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Research Papers
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Tatsuro NAKAGAMA, Toshiaki MORITA, Tsuneaki MAEDA, Katsumi UCHIYAMA, T ...2002 Volume 51 Issue 11 Pages 993-1000
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSA prototype of an atomic emission spectrometric detector using a radio frequency helium plasma (RFP-AED) was constructed for gas chromatography (GC). The outside of a quartz emission tube in the RFP-AED was shielded with helium flow to prevent contamination of atmosphere into the plasma. The correlation of the atomic emission spectra obtained using the RFP-AED and the elemental components of a sample compound were examined. When sixteen compounds, e.g., halogenated aromatics and aliphatics or trihalomethanes, were tested using the GC-(RFP-AED) system, the emission spectra from halogens (chlorine, bromine, fluorine and iodine) in the sample molecules were clearly distinguished. Additionally, a linear relationship existed between the ratio of the emission intensities due to chlorine or bromine and hydrogen, and those elemental ratios. From the results, the identification of halogens and estimations of elemental ratios of chlorine or bromine and hydrogen were performed using the RFP-AED.View full abstractDownload PDF (4387K) -
Masayuki KUNUGI, Kazuo FUJIMORI, Takeshi NAKANO, Akira HARASHIMA2002 Volume 51 Issue 11 Pages 1001-1008
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSHazardous chemicals in the sea are liable to be accumulated in marine ecosystems, and are transported by such mechanisms as oceanic and atmospheric currents. It is important to study these mechanisms in the ocean in order to understand the nature and extent of marine pollution from hazardous chemicals. A continuous-extraction sampling system for hazardous chemicals was developed and set up on a ferry (Kurosiwo). We tested the extraction rate of this system in a laboratory and in situ. The extraction rate was determined to be over 90%. The detection limit in 100 l of extracted seawater was about 5 pg l-1 for chlordane and 10 pg l-1 for HCHs. More than 70 samples were collected on the ferry (Kurosiwo) route from Osaka to Naha. Hazardous chemicals were collected by solid-phase extraction and analyzed by the GC/MS-SIM method. We determined the levels of hazardous chemicals, such as trans-chlordane, which ranged from the detection limit to 50 pg l-1, and α-HCH and β-HCH, which varied from 30 to 800 pg l-1. The spatial distribution of β-HCH was similar in all observations, while that of α-HCH varied with the weather condition.View full abstractDownload PDF (5026K) -
Yuichi HORII, Makoto OKADA, Kazuo AMANO, Nobuyasu HANARI, Sachi TANIYA ...2002 Volume 51 Issue 11 Pages 1009-1018
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSPolychlorinated naphthalenes (PCNs) were used in a variety of industrial products including capacitor dielectrics; cutting oils; engine oil additives; die casting; ship insulation; wood, paper, and fabric preservatives; and wire insulation. The technical formulations of PCNs, polychlorinated biphenyls and other industrial thermal processes (e.g. incinerator, chloro-alkali plant) are considered to be additional sources of environmental contamination by this compound. PCNs are planar, similar to polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs); therefore, some PCN isomers elicit toxicy similar to that of PCDD/DFs. Vertical profiles of residues in dated sediment cores have been used as historical records of pollution. Our studies examined the vertical profiles of persistent organic contaminants, such as PCNs, PCBs and PCDDs/DFs, in a sediment core from Lake Kitaura. Heretofore, an analytical method of PCNs with insufficient performance was used. We developed a new method which conbined on accelerated solvent extractor, double column HPLC system with a porous graphitic carbon column (Hypercarb) and a pyrenyl-silica (PYE) column, preparative GC and HRGCHRMS. The profile was characterized by lesser concentrations in deeper layers, followed by an exponential increase to a subsurface peak and a gradual decrease to the surface. A maximum PCNs concentration of 733 pg/g, dry wt was found in a 14∼15 cm section, which corresponded to the early 1980s. The composition of PCN isomers in environmental samples is characteristic of their sources. The profile of isomers typical to Halowax showed a similarity in which the maximum concentration occurred in the 14∼15 cm section. In surface layers these isomers gradually decreased. The profile of combustion source isomers was very interesting because these concentrations increase or don't decrease very remarkably from the 14∼15 cm section to the surface. Although this suggests sources originating from incineration, there may also exist photodecomposition or biodegradation of HxCN and HpCN isomers resulting in the formation of lower chlorinated isomers, which are included in technical PCBs as impurities.View full abstractDownload PDF (6478K)
Technical Papers
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Chiyoko MIYAGI, Kikuko OOMURO, Yosirou TAKIZAWA, Nobuyuki MORITO2002 Volume 51 Issue 11 Pages 1019-1026
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSPrecise individual determinations of ultratrace amounts of carbon and sulfur in iron and steel samples had already been established by means of an infrared absorption method after combustion in an induction furnace. In the present work we investigated how to improve the accuracy of the simultaneous determination of ultratrace amounts of carbon and sulfur in steel, because of little information being available about this matter so far. The combustion conditions available for a simultaneous analysis were obtained by using a mixed accelerator of tungsten (0.5 g) and tin (0.18 g) with 1.0 g of a steel sample, at a while aiming high analytical intensity and good accuracy. Blank analytical values of carbon and sulfur in a ceramic crucible and combustion accelerators could be effectively reduced by heating the ceramic crucible with accelerators at 460°C for longer than 15 min, after preheating the crucible at 1110°C for 2 hours. Surface contamination of the steel sample could be removed by placing it into the ceramic crucible under a high-temperature state. In order to obtain a stable sulfur analytical intensity, it was effective to perform a preliminary combustion of a specimen with a higher sulfur content before analyzing the object sample. A working curve made by the proposed analytical procedure using Japanese Iron and Steel Certified Reference Materials showed good linearity and excellent analytical accuracy in the simultaneous determination of ultratrace amounts of carbon and sulfur in iron and steel samples.View full abstractDownload PDF (2172K) -
Hisatake NARASAKI2002 Volume 51 Issue 11 Pages 1027-1035
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSBisphenol A in river-waters samples was determined by liquid chromatography/mass spectrometry (LC/MS) using solid-phase sorbents. The water samples contained some inorganic salts and humic substances (humic and fulvic acids). Since the humic substances were coextracted with bisphenol A, they interfered with the determination of bisphenol A. Water (300 ml) spiked with 50 ng of deuterated bisphenol A (the surrogate) at natural pH was applied to Accell QMA (strong anion-exchange sorbent) and C18 cartridges using a concentrator at a flow rate of 20 ml min-1. Humic substances were sorbed to the Accell QMA cartridge, while bisphenol A was mainly sorbed to the C18 cartridge. After the C18 cartridge had been eluted with 5 ml of ethyl acetate, the eluate was dehydrated with anhydrous sodium sulfate. The eluate was evaporated to dryness at 35°C under a stream of nitrogen gas. The residue was dissolved in 1 ml of acetonitrile. The concentration of bisphenol A was determined by the operating conditions, as shown in Table 1. When the water samples were densely colored, the humic substances in them could not be completely removed by the above procedure. No difference was found in the recoveries of bisphenol A between pH 3.5 and 7.0. The determination limit of bisphenol A was 5 ng ml-1.View full abstractDownload PDF (764K)
Notes
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Junichi ISOE, Yasuhiro SAKAI, Emiko KANEKO, Shingo SAITO, Suwaru HOSHI ...2002 Volume 51 Issue 11 Pages 1037-1040
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSA rapid and simple method has been developed for the determination of trace lead ion using an octadecylsilanized (ODS) silica disk cartridge. The ion-pair of a lead complex with 5,6-14,15-dibenzo-4,7,13,16,21,24-hexaoxa-1.10- diazabicyclohexacosane (DBC 2.2.2) and tetrabromofluorescein (Eosin Y) was extracted from a sample solution onto an ODS filter at pH 7.0. It was found that the addition of 20 wt% ethanol to the sample solution significantly enhanced the solid phase extraction. The lead concentration was determined by visual fluorimetry under ultraviolet light in the dark. The ion-pair has excitation and emission maxima at 530 nm and 560 nm in the solid phase, respectively. When measured with a densitometer, the linear range of this method is up to 2.9×10-8 mol dm-3 (6 ppb). The detection limit is 5.0×10-10 mol dm-3 (100 ppt) by visual determination and 3.4×10-9 mol dm-3 (700 ppt) by densitometry. The relative standard deviation for 1.2×10-3 mol dm-3 (2.3 ppb) of lead is 5.6% (n=7). The method is essentially free from matrix interference. The proposed method can easily be performed and provides good precision and accuracy.View full abstractDownload PDF (336K) -
Hiromiti SAWAMOTO, Setsuko KASHIMORI2002 Volume 51 Issue 11 Pages 1041-1044
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSThe adsorption of 1-pentanol, ribofravin and thioctic acid on a gold electrode was studied by measuring diffferential capacity-potential curves. The differential capacity was measured by a phase sensitive ac polarograph (Fuso Model 332 and 333). The frequency used was 25 Hz and the amplitude was 5 mV. The gold electrode was prepared by sealing a commercially available gold wire in a glass tube. The cyclic voltamograms for riboflavin and thioctic acid are shown in Fig. 1. The voltamogram for riboflavin has a clear reduction peak and an oxidation peak on a gold electrode as on a mercury electrode. Although the voltamogram for thioctic acid has no clear peak, reduction steps can be observed. 1-Pentanol was not reduced or oxidized on a gold electrode as was on a mercury electrode. Differential capacity-potential curves for 1-pentanol, riboflavin and thioctic acid are shown in Figs. 2∼4. A depression of the differential capacity in the presense of 1-pentanol and thioctic acid was observed over the whole potential range investigated (Figs. 2 and 4). At around -0.5, V peaks due to reduction were observed for riboflavin. In the negative potential range, adsorption was also observed, which means that leucoflavin is also adsorbable. The isotherms for these compounds fit the Langmuir isotherm. The free energy of adsorption for 1-pentanol, riboflavin and thioctic acid were 14.6∼18.8, 33.9∼36.8 and 34.7∼38.9 kJ/mol, respectively.View full abstractDownload PDF (400K) -
Susumu SHIMOYAMA, Yasuko NODA, Nobuaki KUCHITSU2002 Volume 51 Issue 11 Pages 1045-1047
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSIt is well known that the detection of light elements is difficult using a portable X-ray fluorescence spectrometer with 241Am (1.85 MBq) as the radiation source. In this study, 55Fe (3.7 MBq) was used as the radiation source instead of 241Am, and the beryllium cover of the detector window was thinned in order to increase the sensitivity. As a result, light elements from Si to K could be identified by the investigated method. This method will be effective to specify mineral pigments of mural paintings.View full abstractDownload PDF (303K)
Technical Letters
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Kensaku OKAMOTO, Akio YASUHARA, Mariko MURAYAMA, Takesi NAKANO, Katash ...2002 Volume 51 Issue 11 Pages 1049-1062
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSThe Japan Society for Analytical Chemistry has developed two new certified reference materials (CRMs) for dioxins, coplanar PCBs and 1∼10 chlorinated PCB homologues. A project team was organized to prepare 2 kinds of river sediment and to certify the concentration of dioxins and so far. An interlaboratory comparison test was performed by participation of 16 laboratories. In statistical analysis, z-scores in the Robust method was applied to reject outliers and followed by usual statistical procedure. The presented CRMs are expected to be useful for quality assurance and quality control of dioxins analysis.View full abstractDownload PDF (4268K) -
Hirokatsu TAKEMI, Hokuto SHIDAWARA, Kazuaki ITO, Yoshio HASHIMOTO, Fum ...2002 Volume 51 Issue 11 Pages 1063-1068
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSIn the history of the discovery of rare-earth elements, two elements, Pr and Nd were isolated by Brauner (1882) from a rare-earth sample (Didym) which was considered to be mono-element and their atomic numbers were also determined. In this study, the oxide sample employed in the separation processes was analyzed using two coupled analytical methods, ion chromatography/neutron activation analysis (IC/NAA) and isotachophoresis/particle induced X-ray emission method (ITP/PIXE). Four rare-earth elements were only determined by NAA of 40 μg of Digym. Whereas for IC/NAA with preseparation process, 13 rare-earth elements containing 0.004 mass% Yb were determined when 100 μg of Didym was analyzed. For ITP/PIXE, 12 rare-earth elements were determined. The results obtained by the coupled analytical methods agreed with each other. Although the content of Ce in the sample (Didym) obtained from Cerite was very small, that of La was large, suggesting that chemical treatments to remove La had not been achieved.View full abstractDownload PDF (560K) -
Hideaki KITAMI, Tetsuo WATANABE, Takio KITAHARA, Yoshimi ISHIHARA, Jir ...2002 Volume 51 Issue 11 Pages 1069-1073
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSWe studied a simple method for the simultaneous determination of simazine, thiuram, and benchiocarb in distilled water and river-water by high-performance liquid chromatography (HPLC) with an ultraviolet detector (UV). As a result, good linearity of the calibration curve was obtained in the concentration range from 0.01 mg l-1 to 0.5 mg l-1. The detection limits based on S/N=3 were 1.0 μg l-1 for simazine, 4.5 μg l-1 for thiuram, and 6.5 μg l-1 for benchiocarb. Solid-phase extraction using activated carbon and elution with acetone was recommended for enriching the three pesticides. The recoveries from 200 ml of spiked river water samples at a concentration level of 2.5 μg l-1 were 88.6∼93.8%, and the relative standard deviations were 4.9∼5.3%. This analytical method could be successfully applied to the determination of three pesticides in river water.View full abstractDownload PDF (484K) -
Ayano SEKIMOTO, Kensaku HORIE, Tomokazu MATSUMOTO, Hiroki HARAGUCHI2002 Volume 51 Issue 11 Pages 1075-1084
Published: November 05, 2002
Released on J-STAGE: March 13, 2009
JOURNAL FREE ACCESSMajor-to-ultratrace elements in sediment, rock and clay samples were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). The analytical results were compared with each other from geochemical points of view. In the case of Lake Biwa sediment reference material (JLk-1), the sample was decomposed by both alkali fusion using LiBO2 and acid digestion using HF. From a comparison of the analytical results obtained by different digestion methods, it was found that volatile elements, such as Zn, Cu, Ni and Co, provided lower values in alkali fusion than those in acid digestion. On the other hand, acid digestion was not efficient enough to decompose zircon (ZrSiO4) completely. As a result, the analytical value of Zr as well as heavy rare earth elements was significantly low, compared to reference values. The analytical data obtained for the sediment, rock and clay samples were compared, especially in terms of enrichment factors for major elements and the distribution patterns for rare earth elements. Some similarities of the distributions of major and rare earth elements were found for lake sediment and clay used as pottery material.View full abstractDownload PDF (1040K)
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