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Volume 43, Issue 8
Displaying 1-12 of 12 articles from this issue
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Masae YUKAWA1994 Volume 43 Issue 8 Pages 583-602
Published: August 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSRecently physiological roles of trace elements in the human body in relation to intoxication and deficiency have attracted much attention from investigators in medicine and biology. Particle indeced X-ray emission (PIXE) analysis has high sensitivity for determination of trace elements in biological and makes it possible to observe the distributions of trace elements in a small sample simultaneously and non-destructively. In this paper, application of the PIXE method to investigate the relation between the elemental distribution and the histological structure of the tissues is described. And various concerning diseace-induced changes of trace element concentration in tissues are introduced.View full abstractDownload PDF (7402K) -
Suwaru HOSHI, Hideki FUJISAWA, Masayuki UTO1994 Volume 43 Issue 8 Pages 603-607
Published: August 05, 1994
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSAmberlite XAD-7 resin coated with dimethylglyoxal bis(4-phenyl-3-thiosemicarbazone)(DMBS) was prepared, and applied to the preconcentration of trace Hg(II) from aqueous solution. Hg(II) was quantitatively collected with the resin coated with the reagent (DMBS-XAD7) from acidic solution by the batch method. After collection, Hg(II) was eluted easily as its DMBS chelate with a small volume of N, N-dimethylformamide(DMF). This collection and elution method was applied to the determination of trace Hg(II). The recommended procedure is follows: to 100 ml of solution containing up to 1μg of Hg(II) adjusted pH 2 with 5 M nitric acid in a 150 ml screw-capped glass bottle, add 0.1 g of DMBS-XAD7 and shake for 15 min. Filter the solution with a polyethylene column (i.d. 9 mm×65 mm height), and then elute Hg(II)-DMBS chelate from the resin with 1 ml of DMF, and inject 5μl of the DMF solution to HPLC with spectrophotometric detection by using an ODS column (i.d. 6 mm×250 mm in length) and 80(v/v) % acetone-water mixed solution as a mobile phase. The calibration curves of peak height was linear in the concentration range of 0.11μg for Hg(II) (0.0025 absorbance unit full-scale at 415 nm). The relative standard deviation (sample size concentration of 0.5μg and 5 determinations) was 2.2%. The proposed method was applied succesfully to the determination of mercury in hair (NIES standard sample) and other.View full abstractDownload PDF (476K) -
Xing-Zheng WU, Kouji SASAKI, Eigo KOBAYASHI, Toshiyuki HOBO1994 Volume 43 Issue 8 Pages 609-613
Published: August 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA disadvantage of the electrokinetic or electromigration injection method in capillary electrophoresis is the sample bias caused by differences in the electrophoretic mobilities of the sample ions. This sample bias problem can be eliminated by isolating the sample-introducing end of the capillary from the injection electric field, since, in this case, the sample solution is pulled into the capillary by the electroosmotic flow independently of the electrophoretic migrations of the sample ions. This paper reports an injection method using the pulling action of the electroosmotic flow. The sample-introducing end of the capillary is isolated from the injection electric field by utilizing an on-column Nafion joint. In order to demonstrate that the sample bias problem is eliminated in the method, p-hydroxylbenzoic acid (1) and nicotinic amide (2) were selected as model samples since they have different electrophoretic mobilities. The model sample is dissolved into the Na2B4O7-NaOH buffer solution (pH 10.5). After the sample is introduced into the capillary, electrophoresis is carried out under an electric voltage of 20 kV. The ratio of peak areas S1/S2 of the model samples (1) to (2) are calculated from the electropherogram obtained with a UV detector. The values of S1/S2 for the conventional electrokinetic injection method, the gravity flow injection method, and the present method are compared. Experimental results show that the value of S1/S2 for the conventional electrokinetic method is much larger than that for the gravity flow method; moreover, the value of S1/S2 increases with the injection voltage. On the other hand, the value of S1/S2 for the present method is the same as that for the gravity flow method, and does not vary with change in the injection voltage.View full abstractDownload PDF (639K) -
Kunihiro WATANABE, Ryota NISHIMORI1994 Volume 43 Issue 8 Pages 615-620
Published: August 05, 1994
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSThe analysis of the average valence of copper in superconductor Y-Ba-Cu-O was investigated by spectrophotometry of a redox reaction. Ascorbic acid was oxidized with copper(II) to form dehydroascorbic acid, which reacted with ο-phenylenediamine. The product was a kind of quinoxaline derivative having a maximum absorption at 340 nm. Therefore, the amount of copper(III) was determined from the obtained absorbance after correction for copper(II) concentration. Oxygen in the sample solution interfered with the determination of average valence by oxidation of ascorbic acid. In this case, the oxygen was removed by addition of sodium thiosulfate. The recommended procedure was as follows : 2590μg of sample was added to 2 ml of a 4% ascorbic acid solution, after first removing dissolved oxygen by nitrogen bubbling. The solution was let stand for 5 min in order to dissolve the sample under nitrogen bubbling. Then, a 1 ml aliquot of sample solution was added to the 2 ml of 0.1% ο-phenylenediamine solution containing sodium thiosulfate (0.15 % ), and left standing for 30 min at room temperature. The absorbance of the sample solution was measured at 345 nm against a reference of distilled water. On the other hand, the total amount of copper in the sample must be determined in order to obtain the average valence of copper. The total amount of copper was determined by using the catalytic behavior of copper on the oxidation of ascorbic acid with oxygen in the sample solution. The temperature (40°C) and reaction time (20 min) were controlled strictly. The working curve obtained was linear over the range of 00.15 ppm. The sample solution remaining from the determination of copper(III) was used for the determination of total amount of copper. The results of sample determinations agreed with those obtained by the conventional method. The minimum amount of sample required for the determination was 25 μg.View full abstractDownload PDF (867K) -
Shoji MOTOMIZU, Masayosi KUWABARA, Mitsuko OSHIMA1994 Volume 43 Issue 8 Pages 621-628
Published: August 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSCapillary electrophoresis study was carried out by using 2-nitroso-1-naphthol-4-sulfonic acid (nitroso-NW acid) as a chelating and chromogenic agent. Nitroso-NW acid (H2R) reacts with Co2+ to form the chelate anion, CoR33- and also reacts with Fe2+, Ni2+, Cu2+ and Pd2+. However, except for Ni2+ and Cu2+, sharp peaks could not be obtained with a conventional carrier containing HR-and buffer components. This is probably because the metal chelates were highly charged: the chelates of Ni2+, Cu2+, Fe2+, Co2+and Pd2+ are expected to be CuR22-, Fe(II)R34- Co(III)R33-, NiR34- and Pd(OH)22 R-, from their electrophoretic mobilities. The peaks of Fe2+, Co2+and Pd2+ were sharpend by adding a quaternary ammonium ion to the carrier. The quaternary ammonium ion in the carrier acts as a pairing cation of metal chelate anions. Of these, tetrabutylammonium ion(TBA+) was the best pairing ion for the metal chelates. By using a carrier containing HR-, TBA+ ·Br- and buffer components (pH 7), good separation and highly sensitive detection of the five metal ions (Fe2+, Co2+, Ni2+, Cu2+and Pd2+) could be achieved within 7 min. The proposed method was applied to the determination of cobalt in nickel salts.View full abstractDownload PDF (1030K) -
Takashi IMAGAWA, Yoshitaka YAMAMOTO1994 Volume 43 Issue 8 Pages 629-633
Published: August 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSPolychlorinated naphthalenes (PCNs) are pollutants often found in environmental samples. Only limited standards of individual PCN isomers are available. 'Halowax' is the most popular technical PCN mixture, but the composition is not clear. In this study, a method to determine the congener composition of a PCN mixture was established using GC with an atomic emission detector (AED), which can detect PCNs with a sensitivity proportional to the number of chlorine atoms in the molecule. Congeners of Halowaxes were identified by measuring the carbon to chlorine ratio. Isomers were identified according to the reported elution order. The amount of each congener was determined from the peak area of chromatogram measured for the emission of chlorine. The relative sensitivities were evaluated for the congeners lacking quantification standards using 1, 2-dichloronaphthalene, 1, 2, 3, 4-tetrachloronaphthalene and octachloronaphthalene. Thus, the congeners constituting each Halowax were determined and the total concentrations were in the range of 93103 % of the calculated value. The isomer composition was almost the same as the value given by MS measurement.View full abstractDownload PDF (539K) -
Yasuo ONARI1994 Volume 43 Issue 8 Pages 635-639
Published: August 05, 1994
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSThe spectrophotometric and the flow injection determination of aqueous ozone based on the oxidation reaction of 2-(5-bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino) aniline-Fe(II) complex with ozone were examined. The results of the spectrophotometric technique are as follows. The apparent molar absorptivity for ozone added at λmax 560 nm was 3604 dm3 mol -1 cm -1. The calibration curve showed good linearity (number of samples, 6; correlation coefficient, 0.9998; significant level, 0.001), and rapid determinations of sub mg dm -3 mg dm-3 levels of aqueous ozone were achieved. The detection limit of this method was about 30 μg dm-3 O3. The results of the FIA were as given below. The reproducibility of the FIA signal (O3, 1.47 mg dm -3 ; number of samples, 5; RSD, 0.48%) was good, and determinations of sub mg dm -3mg dm-3 levels of aqueous ozone were achieved at a sampling frequency of about 40 samples h-1. Aqueous solutes in usual drinking water{Hardness(as CaCO3) ≤50.83 mg dm-3, Cl-≤9.7 mg dm -3, NO3≤4.1 mg dm -3, SO42-≤25.6 mg dm-3} were shown not to interfere with the ozone determinations by these methods.View full abstractDownload PDF (731K) -
Koji MATSUSAKI, Toshikatsu SATA1994 Volume 43 Issue 8 Pages 641-643
Published: August 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA mixture of ammonium-EDTA, nickel and aluminium nitrates is suitable as a matrix modifier for the removal of sulfate interference in the determination of indium and gallium by graphite furnace AAS. Nickel and aluminium nitrates act as a thermal stabilizer for the analyte in the furnace before atomization. Since analyte and other cations are masked by EDTA, the coexisting sulfates are converted to ammonium salt, which is readily decomposed and eliminated from the furnace during the ashing step. In the presence of 0.1 M nickel nitrate, 0.001 M aluminium nitrate and 0.1 M ammonium-EDTA, when the concentration of sodium and potassium sulfates are below 0.02 M, the interferences of these sulfates are completely removed.View full abstractDownload PDF (341K) -
Nobuo NAKANO, Akihiro YAMAMOTO, Yoshio KOBAYASHI, Kunio NAGASHIMA1994 Volume 43 Issue 8 Pages 645-648
Published: August 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA porous cellulose tape coated with silica gel as the absorbent and impregnated with a processing solution that includes silver perchlorate, p-toluenesulfonic acid, glycerin and methanol is a highly sensitive means of detecting hydrogen sulfide and is stable upon exposure to light. Hydrogen sulfide, absorbed on the surface of the tape, reacted with silver perchlorate to form a stain (silver sulfide), the intensity of which could be measured quantitatively by an optical system to determine the concentration of hydrogen sulfide. A linear relation was obtained between sampling time and relative intensity in the range of 550 ppb of hydrogen sulfide at a constant flow rate of sampling gas. The detection limit (signal-to-noise ratio=3) was 2 ppb for hydrogen sulfide with a sampling time of 5 min and flow rate of 350 ml/min. The sensitivity of this tape was 2.5 times as high as that previously reported. This method is not greatly affected by other gases except for hydride gases such as phosphine.View full abstractDownload PDF (476K) -
Yoshifumi HARADA, Natsuko KURATA, Giichi FURUNO1994 Volume 43 Issue 8 Pages 649-653
Published: August 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSImpurities (Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Ti, Y, Zn and Zr) in sialon powder were determined by the following procedure: A sample (0.5 g) was heated with a mixture of hydrofluoric acid (3 ml) and nitric acid (1 ml) in a Teflon pressure vessel at 170°C for 16 h. The contents of the vessel were transferred into a platinum crucible containing phosphoric acid (4 ml) and heated on a hot plate until the opaque appearance of the content changed to a clear-syrupy fluid. The fluid was diluted to 100 ml with water and used for ICP-AES analysis of all impurity elements except K, which was determined by AAS. It was necessary to match closely the matrix concentrations (H3PO4, Al and/or Y) of the standard solutions with those of sialon sample solutions for the determination of impurities because of interferences of the matrix components. This method was successfully applied to the determination of impurities in commercial sialon samples.View full abstractDownload PDF (686K) -
Kazuyoshi FUJIMURA, Noriyuki WATANABE, Tsuguo SAWADA1994 Volume 43 Issue 8 Pages 655-658
Published: August 05, 1994
Released on J-STAGE: November 18, 2010
JOURNAL FREE ACCESSA highly sensitive analytical method for cyanide was developed by using a conductivity detector in ion chromatography with an alkaline eluent. Dimethylethanolamine (DMEA) as the alkali and formic acid (FA) as the counter ion were good choices in terms of low background conductivity. To shorten the retention time of multi-valence anions such as sulfate and phosphate ion, triethylenetetramine-N, N, N', N'', N''', N'''-hexaacetic acid hexasodium salt (TTHA) was also contained in the eluent. The eluent finally chosen was 20 mM DMEA-1.43 mM FA-20 nM TTHA-0.03 mM borax (pH 10.5). Under these conditions, chloride, cyanide, nitrate, carbonate, phosphate and sulfate were well-separated within 20 min. The detection limit for cyanide was 50 ng/ml. Applications to an environmental sample (river water) and a natural food (apricot) are demonstrated.View full abstractDownload PDF (455K) -
Cheng-Huang LIN1994 Volume 43 Issue 8 Pages 659-660
Published: August 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSDownload PDF (264K)
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