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Volume 52, Issue 2
Displaying 1-7 of 7 articles from this issue
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Accounts
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Shoichi KATSUTA, Yasuyuki TAKEDAArticle type: Accounts
2003 Volume 52 Issue 2 Pages 89-105
Published: 2003
Released on J-STAGE: June 19, 2003
JOURNAL FREE ACCESSThe stabilities of metal ion complexes with crown ethers in solutions are largely dependent on the solvation of each species involved in the complexation equilibria. The transfer activity coefficients of the solutes express the relative strength of solvation in different solvents, and are important for quantitative evaluation of the solvation. In this paper, the transfer activity coefficients between water and polar nonaqueous solvents (acetonitrile, propylene carbonate, methanol, N,N-dimethylformamide, and dimethyl sulfoxide), which we have so far determined for various neutral crown ethers and their alkali metal ion complexes, are reviewed. The effects of the structures of crown ethers on the solvation properties of the crowns and their complexes are also discussed.
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Research Papers
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Yumiko NAKAMURA, Kensuke ONDA, Chikako TAKATOH, Akiko MIYAArticle type: Research Papers
2003 Volume 52 Issue 2 Pages 107-114
Published: 2003
Released on J-STAGE: June 19, 2003
JOURNAL FREE ACCESSSewage treatment plant effluents are suspected to supply natural estrogenic hormones {17β-estradiol (E2), estrone (E1), and estriol (E3)} to environmental water. Because estrogens can be the strong endocrine disruptors, it seems to be very important to investigate their behavior in sewage treatment plants. To achieve this object, an analytical method to quantify estrogens in sewage samples is required. In this study, an analytical procedure based on solid-phase extraction and liquid chromatography/tandem mass spectrometry (LC/MS/MS) was developed. Good linearity of the calibration curve (r>0.998) was obtained in the concentration range from 0.2 ng ml−1 to 125 ng ml−1 for E1, and from 0.5 ng ml−1 to 125 ng ml−1 for E2 and E3; the detection limits were 0.2 ng l−1 for E1, and 0.5 ng l−1 for E2 and E3. The recoveries of the standard samples spiked to sewage water were 98.9∼102.5%. Using this method, the estrogens in a municipal sewage treatment plant and those in a domestic sewage treatment plant were quantified. The obtained data were compared with data obtained by ELISA (enzyme-linked immunosorbent assay) or the estrogen-like activity obtained by a yeast assay. The concentrations of E2 by ELISA were usually higher than those by this method. Also the estrogen-like activity of sewage samples was highly contributed by estrogens. Especially in effluent water, the contribution of E1 was comparably high.
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Kazuya TAKADA, Tetsuo UCHIDAArticle type: Research Papers
2003 Volume 52 Issue 2 Pages 115-120
Published: 2003
Released on J-STAGE: June 19, 2003
JOURNAL FREE ACCESSBatch and flow injection methods were described for spectrophotometric determination of calcium and magnesium in silicates. A powdered sample of 25 mg was decomposed with hydrochloric and hydrofluoric acids at room temperature, and then diluted with water and boric acid to 50 g. The interference from iron (III) was eliminated by preliminary extraction with isopropyltropolone-benzene. Calcium was measured as a glyoxal-bis(2-hydroxyanil) complex in a 0.04 M NaOH and 25% ethanol medium, and magnesium as a Xylidyl blue II complex in a borax buffer (pH 10.4) and 50% ethanol medium containing strontium-O,O'-bis(2-aminoethyl)-ethyleneglycol-N,N,N',N'-tetraacetic acid (EGTA) and triethanolamine (TEA) for masking calcium and aluminum. On the basis of the batch method, the same three streams FIA system was constructed for both elements at the rate of 20 samples/h. The present FIA (and batch) methods gave linear working ranges of 0∼6.0 ppm (0∼1.5 ppm) CaO and 0∼3.0 ppm (0∼0.6 ppm) MgO, the detection limits of 0.03 ppm (0.01 ppm) for CaO and 0.02 ppm (0.008 ppm) for MgO and good reproducibility. The analytical results of both elements in standard rocks with the proposed methods agreed well with each other and with the certified values.
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Kazunari MITSUHASHI, Ryozo YOSHIZAKI, Hidehiko OKADA, Takeshi OHARA, H ...Article type: Research Papers
2003 Volume 52 Issue 2 Pages 121-126
Published: 2003
Released on J-STAGE: June 19, 2003
JOURNAL FREE ACCESSWe have developed a superconducting high gradient magnetic separation (HGMS) system to remove endocrine disrupters from water. The system purified 70 liters of endocrine disrupter polluted water within about several tens of minutes without generating any secondary waste. The system consists of pretreatment processes to form magnetized compounds with endocrine disrupters, and an HGMS device to extract them by using a strong magnetic force from water. We fabricated a novel adsorbent made of micron-sized ferric oxide particles which are not only magnetic but also hydrophobic. Because some of endocrine disrupters are hydrophobic as well, the ferric oxide particles adsorb endocrine disrupters eluted in water according to a hydrophobic interaction. We have succeeded in decreasing the bisphenol A concentrations in fortified water from 69 ng l−1 to 16 ng l−1 and nonylphenol from 7.0 mg l−1 to 0.9 mg l−1. Furthermore, we have successfully demonstrated that we could regenerate the ferric oxide particles, and that they were reusable for the adsorption of endocrine disrupters in water.
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Nobuyasu HANARI, Yuichi HORII, Sachi TANIYASU, Nobuyoshi YAMASHITAArticle type: Research Papers
2003 Volume 52 Issue 2 Pages 127-138
Published: 2003
Released on J-STAGE: June 19, 2003
JOURNAL FREE ACCESSA large amount of preparations using polychlorinated naphthalenes (PCNs) were used for diverse technical appliances (capacitor dielectrics, frame retardant, etc.) in the 1970s. It appeared that pollution from PCNs and its hazardous effects to wildlife should be considered. It has been claimed that it is important to carry out reliable measurement of PCNs without any co-elution problem, because it constitutes 75 isomers, and there are non-negligible types of interferences in environmental samples. We have already developed a double column-HPLC separation method with HRGC/HRMS for sediment core samples. In this study, we applied this to pine needle leaf collected from the Tokyo Bay area to enable the identification of 53 isomers of PCNs and some dioxin-like compounds. Pine needle leaf is known to be a long-term indicator of ambient air pollution instead of short-term air sampling, which is difficult to standardize because of a change in the weather, etc. The concentrations of PCNs were 630 to 1750 pg/g, wet wt., in selected samples of pine needle leaf; tri- and tetraCNs were the predominant homologues. PCNs from incineration in pine needle leaf were greater than those of sediments from the Tokyo Bay.
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Technical Papers
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Tatsuo NAKAGAWA, Toshihiko NAGAMURA, Hajime KARATANI, Takeko MATSUMURA ...Article type: Technical Papers
2003 Volume 52 Issue 2 Pages 139-145
Published: 2003
Released on J-STAGE: June 19, 2003
JOURNAL FREE ACCESSWe developed a time-resolved spectroscopic image analyzer system for the quantitative analysis of physiological phenomena or chemical reactions. We utilized a highly sensitive charge coupled device (CCD) equipped with a thermo-electric cooler as an imaging detector, and also designed a filter wheel with 10 optical filters for a spectrometric device. A binning operation of the CCD also contributed to an improvement of the detection limit. We achieved a time resolution of 200 ms/frame by tuning the digital circuits and control program. To evaluate the performance of the system, we observed non-linear chemical waves by a binocular microscope, and bio-luminescence by a fluorescence microscope. We also developed software which has functions of absorbance calculations, line profiling between two given points and velocity calculations of a moving image of non-linear reaction patterns.
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Notes
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Isamu FUJIWARA, Akemi UCHIYAMA, Yoshiaki SASAKI, Mizuo MAEDA, Makoto T ...Article type: Notes
2003 Volume 52 Issue 2 Pages 147-150
Published: 2003
Released on J-STAGE: June 19, 2003
JOURNAL FREE ACCESSCuII-imprinted microspheres with imidazole groups at the surfaces were prepared from a seed emulsion with divinylbenzene as a matrix-forming monomer and CuII as a template by radical polymerization. The seed emulsion was prepared from the polymerization of 1-vinylimidazole, styrene, and n-butyl acrylate mixture by a radical initiator. The obtained microspheres were uniform-sized spherical particles and their average diameter was 0.44 μm based on scanning electron micrography. The adsorption of the CuII ion (0.05 mM) on these microspheres was studied, and compared to non-imprinted ones. The adsorption of CuII ion increased on both microspheres with increasing pH. The template effect was observed, that is, the pH giving 50% adsorption of CuII ion on CuII-imprinted resin was lower by one unit than that on non-imprinted resin. The template effect was also observed for the ZnII ion, but not observed for the CdII ion.
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