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Hideki WATANABE, Yukio YOKOYAMA, Hisakuni SAT
1996 Volume 12 Issue 3 Pages
381-384
Published: June 10, 1996
Released on J-STAGE: July 04, 2006
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A general, functional relationship between the retention volume of the 2nd system peak and the chromatographic parameters (the acid dissociation constant of the eluent component, the eluent concentration, the acid/salt ratio in the eluent, the acid-partition coefficient) in ion chromatography with monobasic acid eluent systems (acids, salts, and their mixtures) have been derived. The relations precisely reproduced the results by computer simulation based on the plate theory, and were confirmed with independent experiments. By using these relations, the partition isotherm of eluent acids to the stationary phase can be obtained easily.
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Takuya SHIMOSAKA, Takehiko KITAMORI, Akira HARATA, Tsuguo SAWAD
1996 Volume 12 Issue 3 Pages
385-391
Published: June 10, 1996
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Fuzzy sets theory was introduced for quantitative treatment of measured values in ultratrace analysis. The data obtained in extremely low concentration have uncertainties such as errors of measurement or errors arising from chemical handling of the samples. In place of the least squares method, a fuzzy linear regression method was applied to measured values expressed by the fuzzy numbers, and instead of a calibration curve, a calibration area was obtained. The validity and propriety of the calibration area were shown from simulation and experimental data of ultratrace analyses done using laser induced photothermal spectrometry. Analytical meanings of the shape of the calibration area were discussed.
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Reiko OKUMURA, Teruo HINOUE, Hitoshi WATARA
1996 Volume 12 Issue 3 Pages
393-397
Published: June 10, 1996
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By using total internal-reflection fluorescence (TIRF) spectroscopy it was shown that an unprotonated form of water-soluble porphyrin (5, 10, 15, 20-tetraphenyl-21H, 23H-porphinetetrasulfonic acid, TPPS) is preferentially adsorbed over the diprotonated one by the toluene-water or di(2-ethylhexyl)phthalate (DEHP)-water interface in the presence of a cationic surfactant (cetyltrimethylammonium bromide, CTAB). The pH dependencies of the TIRF intensity were satisfactorily analyzed by a simple adsorption model, including the protonation equilibria in the bulk aqueous phase and the adsorption equilibrium at the interface of TPPS. Further, it was found that applying an electric field across the DEHP-water interface significantly changed the ion-association adsorption equilibria. This result was explained in terms of the electrophoresis of TPPS in the interfacial region.
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Keiichi KIMUR, Saeko KANOKOGI, Masaaki YOKOYAMA
1996 Volume 12 Issue 3 Pages
399-403
Published: June 10, 1996
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A spirobenzopyran derivative incorporating monoaza-12-crown-4 moiety was applied as a reagent for extraction spectrophotometry of alkali metal ions, taking advantage of the cation-complexation-induced Isomerization of its spiropyran moiety to the corresponding colored merocyanine form. The present spectrophotometry is quite selective for lithium ion against the other alkali metal ions. Photoisomerization of the crowned spirobenzopyran promoted the lithium extraction; especially, it increased the extraction rate remarkably.
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Meri YAMADA, Satoshi KUSAKABE, Jana PREKOPOVA, Tatsuya SEKINE
1996 Volume 12 Issue 3 Pages
405-410
Published: June 10, 1996
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Solvent extraction of scandium(III), yttrium(III), lanthanum(III), europium(III), gallium(III), indium(III), and chromium(III) in weakly acidified 1mol dm
-3 NaClO
4 solutions with trioctylphosphine oxide (TOPO) in hexane was studied. The extraction equilibrium was established by the two phase agitation for within 3min and the extracted species except chromium(III) were found to be M(TOPO)
43+(ClO
4-)
3. The extraction of chromium(III) was also achieved by the two phase agitation for only a short time but, from the dependence of the extraction on the TOPO concentration, the extracted species was assumed to be Cr(TOPO)
63+(ClO
4-)
3. Since the inert Cr(H
2O)
63+ was so rapidly extracted and the solvation number was higher than that of the other metal ions, the TOPO molecules were assumed to combine with the hydrating water molecules by hydrogen bonds which can be formed in a short time even when the metal ion was inert. The chromium(III) was also extracted rapidly from 1mol dm
-3 NaSCN, NaNO
3, NaBr, and NaCl solutions with TOPO in hexane and the extraction was better from NaSCN solution than from NaClO
4 solution but it was not effective from the solutions of other salts.
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Akinobu NASU, Akihiro YOSHIKAWA, Junji NORO, Tatsuya SEKINE
1996 Volume 12 Issue 3 Pages
411-418
Published: June 10, 1996
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The study concerns the solvent extraction of 10
-5 to 10
-4mol dm
-3 copper originally in the divalent state in 0.1mol Dm
-3 sodium nitrate solutions containing 10
-5 to 10
-3mol dm
-3 thiocyanate, ascorbic acid and tetrabutylammonium ions (tba
+) into chloroform or 4-methyl-2-pentanone (MIBK). The extraction of copper was quantitative in the highest thiocyanate concentration range in the presence of ascorbic acid and 10
-3mol dm
-3 tba
+; no extraction was found in the absence of this reducing reagent. In all the thiocyanate concentrations, the extracted species was found to be in the form of tba
+Cu
I(SCN)
2- but the copper in the aqueous phase containing this reducing reagent and thiocyanate was found to be still predominantly in the divalent state. The results indicate approximately complete dissociation of the extracted ion-pairs in MIBK, but negligible dissociation in chloroform.
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Hiromichi YAMADA, Kyoko YAJIMA, Yujiro NODA, Hiroko WADA
1996 Volume 12 Issue 3 Pages
419-426
Published: June 10, 1996
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By using 1-octanol-benzene and 2-octanone-benzene mixed solvents with a wide variety of mixing ratios, the extraction of copper(II) with benzoic acid was carried out at 25°C and an aqueous ionic strength of 0.1mol dm
-3 (NaClO
4). Each extraction equilibrium for these mixed-solvent systems was determined by a slope analysis and curve-fitting method. The monomeric and dimeric copper(II) benzoates were found to be responsible for all extraction systems. The present results have revealed the relationship between the partition constants of the monomeric extracted species, CuA
2, and monomeric benzoic acid, HA. It has been proven that the present mixed solvents with a certain composition are superior to chloroform in the extraction of copper(II) by benzoic acid.
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Toshiaki HIYAMA, Shinichi SUGAYA, Tomio KAGEYAMA, Katsuichiro KAMIMURA
1996 Volume 12 Issue 3 Pages
427-430
Published: June 10, 1996
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A second-order derivative spectrophotometric method has been developed for the determination of microgram quantities of trivalent americium in a nitric acid medium containing plutonium and uranium. The second-order derivative absorbance of the americium at 503.5nm is used for the quantitative analysis. In the determination of 5.8μg/ml and 3.9μg/ml of americium, the presence of a 100-fold amount of plutonium and a 600-fold amount of uranium could be tolerated, respectively. The trivalent americium, in the concentration range of 1-11μg/ml has been determined with good precision. The detection limit was 0.3μg/ml at 3 times the standard deviation (3σ). The relative standard deviation was less than 2.1% for a sample of uranium-plutonium mixed oxide. The proposed method does not require the complicated separation step of plutonium and uranium.
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Mohamed A. KABIL, Shaban E. GHAZY, Ahmed A. El-ASMY, Yousery E. SHERIF
1996 Volume 12 Issue 3 Pages
431-437
Published: June 10, 1996
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4-Phenylthiosemicarbazide (HPTS) was investigated as a new collector for the flotation of platinum(IV). The metal ion forms a (1:2) pale green complex with HPTS in the aqueous solution. An intense clear green layer was formed, after flotation, by adding oleic acid (HOL) surfactant. The composition of the float is 1:2 (Pt:HPTS). A highly selective and sensitive spectrophotometric procedure was proposed for the determination of microamounts of Pt(IV) as its floated complex. The flotation-determination method was achieved in the pH range 3-7. Beer′s law was obeyed up to 6× 10
-5mol l
-1(11.7ppm). The interferences from various foreign ions were avoided by adding excess HPTS. The molar absorptivities of Pt-HPTS and Pt-HPTS-HOL systems are 2×10
3 and 4.7×10
3l mol-1 cm-1 at 660 and 690nm, respectively. The formation constants of the species formed in the presence and absence of HOL are calculated. The method was successfully applied to the determination of Pt(IV) in its allied materials. A mechanism of flotation is suggested.
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Tatsuya KITADE, Keisuke KITAMURA, Noriko KISHIMOTO
1996 Volume 12 Issue 3 Pages
439-441
Published: June 10, 1996
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The room-temperature phosphorescence (RTP) of six phenothiazine derivatives was investigated using a solid substrate (PVA-CLL) prepared from a mixture of poly(vinyl alcohol) (PVA) and a small amount of cellulose (CLL, 5 wt%). The sample solution spotted substrates were conveniently dried in a microwave oven. The RTP signals of these phenothiazine derivatives could be measured sufficiently, even without any dry gas flush to the sample compartment, since the signals were very stable in the atmosphere. The limits of detection for the phenothiazine derivatives were in the 0.16-2.53ng/spot range; these values proved a higher sensitivity of the PVA-CLL substrate compared with those of filter paper. The calibration curve of promethazine was examined as an instance of these phenothiazine derivatives, and the linearity was confirmed with a correlation coefficient of 0.997 (
n=24) in the range from 2pmol/spot to 1nmol/spot. The relative standard deviation was 10.6% (
n=5) at a level of 40pmol/spot. These results suggest that the PVA-CLL substrate has superior advantages for determining phenothiazine derivatives by the RTP method.
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João R. FERNANDES, Graciliano de Oliveira NETO, Matthieu TUBINO ...
1996 Volume 12 Issue 3 Pages
443-447
Published: June 10, 1996
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A new methodology for soluble oxalic acid determination in grass samples was developed using a two enzyme reactor in an FIA system. The reactor consisted of 3 U of oxalate oxidase and 100 U of peroxidase immobilized on Sorghum vulgare seeds activated with glutaraldehyde. The carbon dioxide was monitored spectrophotometrically, after reacting with an acid-base indicator (Bromocresol Purple) after it permeated through a PTFE membrane. A linear response range was observed between 0.25 and 1.00mmol l
-1 of oxalic acid; the data was fit by the equation
A=-0.8(±1.5)+57.2(±2.5)[oxalate], with a correlation coefficient of 0.9971 and a relative standard deviation of 2% for
n=5. The variance for a 0.25mmol l
-1 oxalic acid standard solution was lower than 4% for 11 measurements. The FIA system allows analysis of 20 samples per hour without prior treatment. The proposed method showed a good correlation with that of the Sigma Kit.
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Ronghui WANG, Qingyun CAI, Lihua NIE, Shouzhuo YAO
1996 Volume 12 Issue 3 Pages
449-453
Published: June 10, 1996
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The regulatory property of NAD
+-Isocitrate dehydrogenase (NAD
+-ICDH) was studied by means of a new device, a surface acoustic wave (SAW) impedance sensor, which comprises a 61MHz SAW resonator and a pair of parallel platinum electrodes. The NAD
+-ICDH is an allosterically regulated enzyme which shows sigmoidal kinetic for DL-isocitrate. The Hill coefficient was estimated to be 2.93. A linear relationship between the frequency response and the enzyme concentration was obtained, and the experimental detection limit was evaluated to be 45mIU/ml. A comparison between the SAW impedance sensor and the conductometric method was carried out. The effects of AMP, ADP and ATP on the kinetic property of NAD
+-ICDH were investigated; some other factors, such as the temperature and pH value, are also discussed.
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Teiichiro OGAWA, Shinichiro SUMI, Takanori INOUE
1996 Volume 12 Issue 3 Pages
455-458
Published: June 10, 1996
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The laser two-photon ionization technique has been applied to a liquid droplet (100-3μl) in order to determine the analytical potential of this technique for a small amount of sample. Surface photoionization was effective to remove the leakage current and allowed use of water as the solvent. Irradiation at the top surface of the liquid drop showed a wider linear range of the analytical curve than irradiation at its middle body. The detection limit of pyrene was 0.3pg.
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Jin-Chun WOO, Dong-Min MOON, Tomokazu TANAKA, Motoya MATSUNO, Hiroshi ...
1996 Volume 12 Issue 3 Pages
459-464
Published: June 10, 1996
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The addition of helium to argon up to 5% significantly decreased the sputtering rate for a brass sample, while about 30% increases of copper and zinc-ion signals were observed upon the 2% helium addition. The normalized ionization efficiencies were calculated from the ratio of the ion intensity and the atom density in the plasma measured by atomic absorption spectrometry. The ionization efficiency at 4% addition of helium was 25-times higher than that for pure argon. No change in the DC self-bias voltage was observed for various additions of helium. These characteristics were compared with the oxygen addition as well as with a DC glow discharge. The differences in the ion-signal behavior between the radio frequency and DC glow discharges are discussed.
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Eiji FUJIMORI, Hideyuki SAWATARI, Koichi CHIBA, Hiroki HARAGUCHI
1996 Volume 12 Issue 3 Pages
465-470
Published: June 10, 1996
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Simultaneous multielement determination of minor and trace elements in the urine reference sample by an ICP-MS/AES combined system is described. The biological reference sample of NIST SRM 2670 Freeze-dried Human Urine (elevated) was used for analysis. The sample preparation was kept to a minimum: the urine sample was diluted 25-fold with 0.1M nitric acid, in which Ge, In and Tl were added as the internal standard elements. Eighteen elements at theμg/ ml-ng/ml levels were simultaneously determined by the present combined system. In addition, the present combined system was also applied to the correction of polyatomic interference in the determination of chromium in SRM 2670, where interference with
52Cr due to
40Ar
12C was corrected by estimating the correction factor of
40Ar
12C from correlation between the ion count of
40Ar
12C and the emission intensity of carbon in the sample.
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Chao Yan ZHOU, Ming Keong WONG, Lip Lin KOH, Yeow Chin WEE
1996 Volume 12 Issue 3 Pages
471-476
Published: June 10, 1996
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Four closed-vessel microwave digestion methods were compared for the accurate determination of mercury in sediments by flow-injection cold-vapor atomic absorption spectrometry. The results showed that several acid mixtures (HNO
3/H
2SO
4, HNO
3/HClO
4, HCl/HNO
3 and HCl/HNO
3/HF) completely digested the soil matrix for the determination of mercury. The method using aqua regia is preferred because it is time saving, less dangerous and suitable for other trace-metal analyses. The merits of pressure-feedback microwave digestion is that it simplifies soil sample digestion, and there is no loss of mercury. The digestion methods were evaluated by determining mercury in NIST SRM 1645 River Sediment, NIES CRM No. 2 Pond Sediment and NRCC BCSS-1 Marine Sediment. Recoveries of 92-108% were achieved. Good recoveries of 94-104% were also obtained for soil and marine-sediment samples spiked with different species of mercury.
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Takashi TOMIYASU, Ayako NAGANO, Hayao SAKAMOTO, Norinobu YONEHARA
1996 Volume 12 Issue 3 Pages
477-481
Published: June 10, 1996
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A method has been proposed for the differential determination of inorganic and organic mercury in environmental and biological materials, based on their successive extraction followed by a cold vapor atomic absorption spectrometric (CVAAS) determination. Mercury was first extracted by shaking a sample with 1M hydrochloric acid containing 3% sodium chloride in the presence of copper(I) chloride. In order to separate organic mercury from inorganic mercury, the extract was shaken with chloroform to extract only organic mercury. The chloroform phase was transferred into a 50ml volumetric flask and 0.4ml of 0.2% dithizone-chloroform solution was added. The contents of the flask was evaporated to dryness, followed by addition of 2ml of 1:1 nitric acid-perchloric acid solution and 5ml of concentrated sulfuric acid and heating at ca. 230°C for 30min. The hydrochloric acid phase containing inorganic mercury was transferred into a 50ml volumetric flask, followed by addition of 1ml of 60% perchloric acid and 5ml of concentrated sulfuric acid and heating at ca. 230°C for 30min. After cooling, the digested sample solution was diluted with water to 50ml. The mercury in each solution was determined by CVAAS. When 0.5g amounts of artificial standard soil samples spiked with a given amount of organic mercury and inorganic mercury {20ng (as Hg) of mercury(II) chloride and methylmercury chloride} were treated by the above-mentioned procedures, the recoveries were 102% and 97.0% with the relative standard deviations of 1.0% and 2.8%, respectively. This method was successfully applied to a differential determination of mercury in sediment, soil and fish meat samples.
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Miguel A. BELARRA, María P. MARTINEZ-GARBAYO, Jesús M. A ...
1996 Volume 12 Issue 3 Pages
483-488
Published: June 10, 1996
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A method for the direct determination of iron and zinc traces in solid rice samples using graphite-furnace atomic absorption spectrometry is proposed. Samples are placed in a graphite tube with a platform, and are determined from integrated absorbance measurements that are interpolated on calibration graphs obtained from aqueous standards of the two metals. The working conditions used allow iron and zinc to be determined at concentrations down to 10μg g
-1 (0.001%) in solid rice samples with a relative standard deviation of 6-10%.
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Kenji HAMASE, Hiroshi NAKAMURA
1996 Volume 12 Issue 3 Pages
489-490
Published: 1996
Released on J-STAGE: July 27, 2007
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Seon-Pyo HONG, Akira SANO, Hiroshi NAKAMURA
1996 Volume 12 Issue 3 Pages
491-493
Published: 1996
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Concepcion S. MENDOZA, Satsuo KAMATA
1996 Volume 12 Issue 3 Pages
495-497
Published: 1996
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Yuji SASAKI, Wuryanto, Hideyo TAKEISHI
1996 Volume 12 Issue 3 Pages
499-501
Published: June 10, 1996
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Naoyoshi EGASHIRA, Osamu MUTOH, Yoshiaki KURAUCHI, Kazuya OHGA
1996 Volume 12 Issue 3 Pages
503-505
Published: June 10, 1996
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Takashi TOMIYASU, Hayao SAKAMOTO, Norinobu YONEHARA
1996 Volume 12 Issue 3 Pages
507-509
Published: June 10, 1996
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Yoshio MORIYA, Mikio SUGAI, Yozo OHSHIMA, Nobuaki OGAWA
1996 Volume 12 Issue 3 Pages
511-513
Published: June 10, 1996
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Munetaka ISHIYAMA, Yoko MIYAZONO, Masanobu SHIGA, Kazumi SASAMOTO, Yos ...
1996 Volume 12 Issue 3 Pages
515-519
Published: June 10, 1996
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Masashi HOJO, Hiroshi HASEGAWA, Yasuhiro MORIMOTO
1996 Volume 12 Issue 3 Pages
521-524
Published: June 10, 1996
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Kazuhiko TSUKAGOSHI, Akiko TANAKA, Riichiro NAKAJIMA, Tadashi HARA
1996 Volume 12 Issue 3 Pages
525-528
Published: June 10, 1996
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Toshiya KOMATSU, Kimiko KOBAYASHI, Tadashi NAKATA, Mie KOBAYASHI, Ken- ...
1996 Volume 12 Issue 3 Pages
529-530
Published: June 10, 1996
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Kimiko KOBAYASHI, Sei TSUBOYAMA, Naoyuki TABATA, Kaoru TSUBOYAMA, Tosi ...
1996 Volume 12 Issue 3 Pages
531-533
Published: 1996
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Manuel SORIANO-GARCÜA, Kaliyamoorthy PANNEERSELVAM, Saúl H ...
1996 Volume 12 Issue 3 Pages
535-537
Published: June 10, 1996
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Manuel SORIANO-GARCÍA, Adela RODRÍGUEZ-ROMERO, Kaliyamoo ...
1996 Volume 12 Issue 3 Pages
539-540
Published: June 10, 1996
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