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Volume 44, Issue 12
Displaying 1-14 of 14 articles from this issue
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Haeng-Boo KIM, Kiyoharu NAKATANI, Hiroshi YAO, Noboru KITAMURA1995 Volume 44 Issue 12 Pages 977-987
Published: December 05, 1995
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSAs the surface area/volume ratio of a particle increases with decreasing particle diameter, interfacial phenomena such as mass transfer, adsorption/desorption, and distribution of analytes at the solution/particle boundary become strongly dependent on the particle size. Here we describe a laser trapping-microspectroscopy technique applicable to spectroscopic measurements of single microparticles in solution and demonstrate the importance of spatially-resolved measurements to investigate heterogeneous chemical systems.View full abstractDownload PDF (2254K) -
Hideyuki ITABASHI1995 Volume 44 Issue 12 Pages 989-999
Published: December 05, 1995
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSMethods for the measurement of copper(II) complexing capacity (CuCC) of natural waters by using a back-extraction of bis(benzoyltrifluoroacetonate) copper(II) (Cu(bfa)2) and the dithizone extraction rate of copper(II) complex were described. From the measurements of CuCC of river water samples, it was found that the CuCC of the water sample in the urban area was larger than that up-stream, due to a ligand originating from human activities. The conditional stability constant (β) of the resulting copper(II) complex was determined by using the back-extraction method.β values of river water samples were 1091010 order of magnitude. Free copper(II) concentration of the Kiryu river was estimated by using the side-reaction coefficient in the extraction of copper(II) with tenoyltrifluoroacetone. The free copper(II) concentration was estimated to be 10-13 mol dm-3 which is 10-5 of total copper. Most of the copper(II) in the river, therefore, is complexed with naturally occurring ligands. A procedure for the measurement of metal complexing capacity by using reverse flow injection analysis (r-FIA) system was also described. The applicability of the method was evaluated by measuring zinc(II), cadmium(II) and lead(II) complexing capacities of both river and lake waters. The values obtained by the r-FIA system were in the same order of magnitude as those obtained by the back-extraction method, indicating the usefulness of the r-FIA method for the estimation of complexing capacity.View full abstractDownload PDF (1761K) -
Shoichi KATSUTA1995 Volume 44 Issue 12 Pages 1001-1012
Published: December 05, 1995
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSEffect of phenols as organic hydrogen-bond donors on the chelate extraction of metal ions was thoroughly investigated. A remarkable enhancement of extractability was found in various chelate extraction systems in the presence of phenols. The selectivity of the effect is quite different from the conventional synergistic effect of neutral electron donors such as tributyl phosphate. From spectroscopic measurements, this effect was ascribed to the association of extracted chelates with phenols through hydrogen bonding in the organic phase. Compositions of the association complexes formed, their stability constants (association constants) and thermodynamic parameters were systematically determined from analysis of the extraction equilibria. On the basis of the association constants obtained, factors governing the hydrogen-bond acceptor ability of metal chelates were elucidated. In this study, an important contribution of hydrogen bonding to chelate extraction was clearly demonstrated.View full abstractDownload PDF (2034K) -
Junko MOTONAKA, Yuji MISHIMA, Sanae IKEDA, Nobuyuki TANAKA1995 Volume 44 Issue 12 Pages 1013-1019
Published: December 05, 1995
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA rapid method is proposed for the determination of an unstable vitamin A-β-carotene mixture by the potentiometric argentimetric titration of stable iodide ions and bromide ions, liberated in proportion to the amount of vitamin A-β-carotene mixture, when treated with iodine or N-bromosuccinimide (NBS) using an iodideselective electrode. The stabilities of the vitamin A-chloroform-methanol solution and β-carotene-chloroform-methanol solution, and the effect of the amount of iodine, NBS, temperature, pH, organic solvent and concomitant compounds, and precision data of vitamin A-β-carotene mixture are discussed. The recommended procedure is as follows. A sample containing 0.32832.8 mg of vitamin A and 0.26826.8 mg β-carotene is taken into a 100 ml-titration cell and treated with 0.110 ml of 20 mM iodine or 0.110 ml of 8 mM NBS. The volume is adjusted with a chloroform-methanol solution to 50 ml and then titrated potentiometrically with a 50 mM standard silver perchlorate solution. The analytical values are corrected using blank test values. This procedure is performed at room temperature (20°C). The whole procedure requires only 20 min. By this method the amounts of vitamin A and β-carotene were obtained by calculation. Vitamin A-β-carotene mixture (0.31631.6 mg vitamin A and 0.26826.8 mg β-carotene) was determined with a relative error of less than ± 7.5 % and a coefficient of variation of less than 6%.View full abstractDownload PDF (1073K) -
Hideki WATANABE, Hisakuni SATO1995 Volume 44 Issue 12 Pages 1021-1025
Published: December 05, 1995
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSEluents for the determination of alkali and alkaline earth metal ions with a conductivity detector and a cation-exchange column of the carboxylate-type were investigated. Nitric acid + ethylenediaminetetraacetic acid, tartaric acid + pyridine-2, 6-dicarboxylic acid and nitric acid + nitrilotriacetic acid (NTA) were used as the eluent. In spite of the same eluent ion (hydrogen ion), the peak areas varied with the eluent compositions. Computer simulations based on plate theory showed that, in the analyte zone, the decrease in the hydrogen-ion concentration was relaxed by dissociation of the eluent acid. A theoretical relation between the peak areas and the chromatographic parameters was derived. The relation was confirmed to be valid by experiments. The retention time of alkaline earth metal ions varied with the presence of a complexing agent in the eluent and with the sample concentration. Nitric acid+ NTA was the most adequate eluent, because the detection sensitivity of the alkali metal ions was relatively large and the retention time of alkaline earth metal ions could be changed with the concentration of NTA.View full abstractDownload PDF (705K) -
Hidekazu YAMADA, Shin KAJIYAMA, Koyo YONEBAYASHI1995 Volume 44 Issue 12 Pages 1027-1032
Published: December 05, 1995
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA HPLC method for the determination of trace amounts of iodine was developed by utilizing the iodine-catalyzed redox reaction between cerium(IV) and arsenic(III) as a post-column reaction. Iodine in the form of iodide ion was separated from coexisting components on a C18 bonded column with acetonitrile-water (25: 75, v/v) containing 20 mM tetrabutylammonium ion and 20 mM arsenic(III). And the mobile phase eluted from the HPLC was mixed continuously with 1.5 mM cerium(IV)-1.0 M sulfuric acid solution. The amount of iodine (>0.5 μg/l) was determined by measuring the fluorescence intensity (Ex. 305 nm, Em. 350 nm) of the cerium(III) produced by the catalytic action of iodine. The method was applied to the fractional determination of iodide, iodate, and organically-bound iodine in water extracts of soils. The dominant chemical form of iodine in the extract was iodide ion.View full abstractDownload PDF (974K) -
Yasuto KASHIWAGI, Etsuo KOKUFUTA, Takuji KAWASHIMA1995 Volume 44 Issue 12 Pages 1033-1039
Published: December 05, 1995
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe preoxidation, preconcentration and separation methods for the graphite-furnace atomic-absorption spectrometric determination of total selenium (inorganic, organic and suspended undissolved selenium) in complex high salt wastewaters were studied. After boiling a 100 ml portion of wastewater (1 M hydrochloric acid) for 30 min under reducing conditions in the presence of 5 g hydrazinium sulfate, ppb levels of selenium (IV, VI) were quantitatively coprecipitated with 25-500μg amounts of tellurium collector and completely collected on the nitrocellulose membrane filter (pore size: 0.2μm), without interference from coexisting high levels of heavy metal salts. However, organic selenium was not quantitatively coprecipitated with tellurium collector. In this case, the decom-position procedure with potassium permanganate and/or potassium dichromate was required before tellurium coprecipitation. The decomposition of solid and/or suspended. samples by preoxidation was also effective for two types of environmental standard materials, coal fly ashes and pond sediments, respectively.View full abstractDownload PDF (919K) -
Shoji MOTOMIZU, Mitsuko OSHIMA, Kouji MATSUURA1995 Volume 44 Issue 12 Pages 1041-1048
Published: December 05, 1995
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA novel background suppressor method in conductivity detection/ion chromatography for inorganic anions was developed. The eluent used was a dodecyltrimethylammonium hydroxide (C12H25-TMA+OH-) solution; a dodecylbenzenesulfonic acid (H·DBS) solution was used to suppress the background conductivity. The eluate was mixed with the suppressor solution and the ion associate formed was extracted into the micelle of nonionic surfactant (polyoxyethylene (10) octylphenyl ether, Triton X-100) as a mixed micelle. The background conductivity was decreased to 24μS cm-1 by the acid-base neutralization and micelle extraction. For rapid analysis, a carbonate buffer solution (pH 10.8) was used: the solution was prepared by bubbling CO2 into the hydroxide eluent. The elution of sulfate ion with the carbonate buffer was accomplished within 20 min. Chloride, nitrate and sulfate ions in river and tap waters were determined satisfactorily with 1.5 × 10-3 MC12H25-TMA+OH- and CO2 (pH 10.8) as the eluent, and 1.5×10-3 M H·DBS and 4% (w/w) TX-100 as the suppressor solution by injecting 50 μl of sample solution.View full abstractDownload PDF (1343K) -
Norio KAWAI, Kiyotoshi MORISHIGE, Yasuharu NISHIKAWA1995 Volume 44 Issue 12 Pages 1049-1054
Published: December 05, 1995
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSChromatographic behavior of chlorophyll derivatives on reversed phase HPLC was evaluated using four parameters : inorganicity/organicity ratio, group electronegativity, molar volume and molar refractivity. For ten pigments, chlorophyll a and b, , pheophytin a and b, pyrochlorophyll a and b, pyropheophytin a and b and methyl pheophorbide a and b, the plot of the natural logarithm of the capacity factor, ln k', against the inorganicity/organicity ratio was linear. However, the plots of ln k' against group electronegativity, molar volume and molar refractivity were not linear. A plot of ln k' against the inorganicity/organicity ratio of the mobile phase, examined in analogy with a plot of ln k' against Snyder's parameter P', was linear. The large variations of interactions, dipole interaction or dispersion force, between the solutes and the two phases caused the plot of ln k' against the inorganicity/organicity ratio to be nonlinear. However, the inorganicity vs. organicity plot, namely the organic conceptional diagram, readily affords the relationships between the polarities of the solutes, the mobile phase and the stationary phase. Therefore, the effectiveness of the inorganicity/organicity ratio for retention predictions of solutes on HPLC became apparent.View full abstractDownload PDF (883K) -
Yasuyuki HOSHIKA, Yoshimasa NIHEI, Giichi MUTO1995 Volume 44 Issue 12 Pages 1055-1057
Published: December 05, 1995
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSDetermination of trace amounts of acetone at (sub-ppm level) in air by atmospheric pressure ionization mass spectrometry (API-MS) was studied. Air samples were directly introduced to the ion source of the instrument without pre-concentration. This technique (positive mode) is also used for real-time analysis of air samples with rapid scanning, and has been shown to be highly sensitive for acetone (at sub-ppm levels). The peaks at m/z 19, 37, 55, 73, 91, corresponded to protonated water clusters of (H2O)H+, (H2O)2H+, (H2O)3H+, (H2O)4H+, and (H2O)5H+, respectively. The peak at m/z 47 was due to (C2H5OH)H+, and that at 59 due to ((CH3)2CO)H+ (acetone). They showed good repeatability with a relative standard deviation of less than about 5%. The API-MS voltage response produced a straight line in the approximate range 0.01 to 0.1 ppm of acetone in air.View full abstractDownload PDF (345K) -
Hiromasa KATOH, Masuko TANAKA, Naoko KATAYAMA, Toshiyuki KAMO1995 Volume 44 Issue 12 Pages 1059-1062
Published: December 05, 1995
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe measurement of bromine index has been mainly carried out with a volumetric titrator. An apparatus for measuring the bromine index has not been easily available. In the present paper, the bromine index was determined by coulometry, using the coulometric Karl Fischer moisture meter. Adopting a lower polarization current than that of the Karl Fischer moisture meter, the measurement of a low bromine index became possible. And, the observed values of the reformed coulometric moisture meter showed good agreement with those of the volumetric titrator.View full abstractDownload PDF (668K) -
Miki SATO, Takanori INOUE, Teiichiro OGAWA1995 Volume 44 Issue 12 Pages 1063-1065
Published: December 05, 1995
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe laser multi-photon ionization technique via an excited state has been found to be a sensitive method for detecting photoabsorbing molecules in solution and on the surface. The photoionization signal tends to decrease in the course of time due to the photodecomposition of molecules and the accumulation of the space charge, especially when a strong laser keeps irradiating a small region of a sample. In order to avoid such difficulties we made new photoionization cells in which the signal intensity could be stabilized by rotating the photoionization cell or stirring the sample solution, thus making the decrease of signal intensity negligible.View full abstractDownload PDF (500K) -
Sachio TANAKA, Masaru OGATA1995 Volume 44 Issue 12 Pages 1067-1070
Published: December 05, 1995
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA simultaneous determination method for bentazone (BTZ) and bensulfronmethyl (BSM) in environmental water was developed. The pH of 1000 ml of water sample was adjusted to 0.52.0 with hydrochloric acid, and then the water sample was extracted with three 150 ml portions of ether. The ether extract was concentrated to 5 ml with a rotary evaporator, and dried-up under an air stream. The residue was dissolved with 3ml of acetonitrile. The clean-up procedure of the acetonitrile solution was developed using a Accu BOND C-18 cartridge. Recoveries of BTZ and BSM were measured by HPLC with photodiode array detector. Recoveries of BTZ and BSM from pure water were about 90%. Those from lake and river waters were 7788%. The coefficient of variation was in the range 0.43.2% for BTZ and 2.05.3% for BSM and the detection limit was 0.5 μg/l for BTZ and 1.0 μg/l for BSM when 1000 ml of sample was used. The present method was successfully applied to the determination of BTZ and BSM in lake, ground, sea and river waters.View full abstractDownload PDF (580K) -
Wataru YOSHIMURA, Xue Dong LIU, Atsushi UZAWA1995 Volume 44 Issue 12 Pages 1071-1076
Published: December 05, 1995
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSBismuth contents in sea water, spring water and river water were determined by means of coprecipitation with zirconium hydroxide and differential pulse anodic stripping voltammetry. Fifty milliliters of sample solutions were added to constant amounts of bismuth standard solution respectively. After 1 ml of zirconium oxychoride solution was added, the pH was adjusted to 9.0 with ammonia water (1: 2). The precipitate was separated by filtration and dissolved in 25 ml of 4 M hydrochloric acid. This solution was diluted to 50 ml with distilled water. A portion of this solution was employed for the determination of bismuth. After bubbling nitrogen gas through the sample solution for 100 s, it was pre-electrolyzed for 100 s. The potential was scanned from-0.5 V to 0 V vs. SCE for dissolution of bismuth. Bismuth ion was determined from the peak current of the voltammogram. The results are as follows: (1) Zirconium hydroxide is the most effective collector of bismuth when the pH is adjusted to 9.0 with ammonia water (1: 2), (2) The analytical procedure takes about 90 min for the determination. (3) This method is applicable to the determination of trace amounts of bismuth in seawater, spring water and river water.View full abstractDownload PDF (796K)
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