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Volume 40, Issue 1
Displaying 1-15 of 15 articles from this issue
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Takashi MASADOME, Toshihiko IMATO, Nobuhiko ISHIBASHI1991 Volume 40 Issue 1 Pages 1-6
Published: January 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA flow system for the determination of cationic surfactants in the presence of anionic surfactant is proposed. The system consists of a micro-column packed with anionexchange resin and a surfactant-selective polyvinyl chloride membrane electrode detector. The membrane was plasticized with phthalic acid di(2-ethylhexyl) ester. Anionic surfactants were removed by the anion-exchange resin column. The cationic surfactant was eluted by methanol/H2O=50/50(v/v, %) and detected. The electrode detector showed the linear response with a potential slope of 45 mV/decade for dodecyltrimethylammonium (DTA) ion from 5×10-7 to 1×10-5 M. The detection limit for DTA was 1.0×10-8M. The proposed method was free from interferences from coexisting inorganic electrolytes, anionic surfactants and nonionic surfactants. By this method, a trace level of cationic surfactants in river water could be determined.View full abstractDownload PDF (801K) -
Takashi MASADOME, Toshihiko IMATO, Nobuhiko ISHIBASHI1991 Volume 40 Issue 1 Pages 7-11
Published: January 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA flow injection system for the determination of nonionic surfactants in the presence of ionic surfactants was investigated. The system consists of a micro-column packed with an ion-exchange resin and a surfactant-selective electrode using a plasticized polyvinyl chloride membrane containing no ion-exchange site. Ionic surfactants were removed on the micro-column. Nonionic surfactants passed through the column with ethanol/H2O=50/50 (v/v, %) were detected. The electrode showed the cationic potential response with a slope of 40 mV/decade for Triton X-100 from 4×10-5to 5×10-4 M. The detection limit of Triton X-100 was 1×10-5 M. The proposed method is free from the interference of coexisting inorganic electrolytes in sample solutions. By this method, nonionic surfactants in detergent samples could be determined.View full abstractDownload PDF (524K) -
Yoshihisa UCHIDA, Tsutomu NAGAOKA, Kotaro OGURA1991 Volume 40 Issue 1 Pages 13-18
Published: January 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSOxidized glassy carbon fiber can take up cations when the fiber is charged electrochemically. We investigated the mechanism of ion uptake in the fiber treated by heat. The uptake amount was dependent on both the rate of oxygen supply and oxidizing time in pretreatment. The amount of ions taken up into the heat-treated fiber was smaller than that for the fiber treated electrochemically. Although the physical surface structures of both the fibers were very similar, their chemical structures were very different. The plots of the uptake amount vs. the pore parameters indicated that ions were adsorbed, on the pore surface as a monolayer. The fiber treated by heat had higher proton selectivity, which was attributed to the adsorption sites different from those created electrochemically.View full abstractDownload PDF (781K) -
Osamu FUJINO, Yasuo KOGA, Keizo HIRAKI1991 Volume 40 Issue 1 Pages 19-24
Published: January 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSICP-AES was used to determine trace amounts of phosphate ion in natural water. Although plasma atomizer showed extremely high atomic emission intensity for phosphorus, its direct determination in natural water is difficult because of the spectral interference from silicate and iron ion and the very low phosphate ion contents in seawater. Therefore, natural water samples were pretreated using a separation process to remove interfering elements and concentrate phosphate ion. This process consisted of a solvent extraction using hydrochloric acid-molybdate as complexing agent and 1-octanol, which has a lower solubility in water, as the organic solvent was suitable for ICP. Samples of natural water, which had been previously filtered through a 0.45 μm Millipore filter were analyzed. Each aliquot of the test sample, 50250 ml, was adjusted to 0.5 mol/dm3 with hydrochloric acid. Five percent ammonium molybdate (525 ml) and 5 ml of 1octanol were added. After shaking and centrifugation, the organic phase was injected directly into the ICP, operating conditions : 1.8 kW RF power, 0.40 l/min carrier gas, 18 l/min coolant gas and 1.1 l/min plasma gas. The detection limit (3σ) of phosphorus was ca. 0.05 μg/ml at the 214.9 nm. The phosphate ion in water from Lake Biwa was 1232 μg/ml.View full abstractDownload PDF (655K) -
Yukikazu HATTORI, Hitoshi YAMAMOTO, Kanji NAGAI, Kazuyo NONAKA, Hiroka ...1991 Volume 40 Issue 1 Pages 25-31
Published: January 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSTributyltin (TBT) and triphenyltin compounds (TPT) in industrial waste water were determined by GC with flame photometric detector (FPD) using tripentyltin chloride (Pe3SnCl) as a surrogate compound. A volume of water sample (1l) was mixed with 10 ml of hydrochloric acid and 20 g of sodium chloride and then extracted twice with 100 ml of hexane. The extract was dehydrated with anhydrous sodium sulfate and concentrated to a small volume (ca. 5 ml) using a rotary evaporator. The concentrate was propylated with 1 ml of 2 mol/l n-propylmagnesium bromide/tetrahydrofuran. Reaction product was passed through Sep-pak Florisil cartridge column and eluted with 5(v/v) % -diethylether/hexane. The eluate was concentrated to about 2 ml. Three microliters of the concentrate was analyzed by GC equipped with a capillary column (0.53 mm i.d.×30 m) coated with 1.5 of DB-5 and FPD. TBT and TPT in industrial waste water from ship building, paint manufacture, and pharmaceutical factory were analyzed by this method. Recovery of TBT and TPT from these water samples was 96104%, 105106%, respectively and the relative standard deviations (R.S.D.) were 2.26.8%, 1.87.3%, respectively. The detection limits were 10 ng/l for TBT (as tributyltin chloride), 30 ng/l for TPT (as triphenyltin chloride). Analysis by GC/MS were also performed. Analytical data by GC/MS agreed well with the data by GC-FPD. R.S.D. by GC/MS were 0.41.7% for TBT, 1.12.5% for TPeT, 1.13.7% for TPT, when standard solution and actual waste water samples were analyzed.View full abstractDownload PDF (615K) -
Natuko KURATA, Yoshifumi HARADA, Giichi FURUNO1991 Volume 40 Issue 1 Pages 33-37
Published: January 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSMetal furnace AAS has been used to determine arsenic (As) in iron, copper and nickel. The proposed analytical procedure is as follows : sample (0.12.0 g) was dissolved in 2030 ml of HNO3 (1+1). The pH except for the case of Fe samples was adjusted to pH 1.02.0 with aqueous ammonia. Arsenic (As) was coprecipitated with manganese dioxide by adding KMnO4 and Mn2+. If more than 50 μg of Sn was contained in Cu or Ni, 0.2 g of Fe had to be added in order to coprecipitate As from HNO3 solution, because Sn(OH)4 was formed in the solution (pH 1.02.0) and it interfere with dissolving the precipitate. The precipitate was dissolved in a mixture of HNO3-H2O2 to which 5 mg of Ca was added and the solution diluted to 50 ml with water. Twenty microliters of this solution was injected into a tungsten boat, and dried at 180°C, for 30 s, ashed at 1500°C for 20 s by ramp mode, and then atomized at 2300°C for 2 s. The absorbance of As was interfered with the matrices of sample solutions, but addition of 100 μg/ml alkaline-earth metals (Ca, Mg and Ba) proved to eliminate these interferences. The same calibration curve prepared with standard solutions could be used for any samples. Fairly accurate results were obtained by this method for NIST, BAS and BAM standards.View full abstractDownload PDF (654K) -
Wenqi QI, Jieshan CAO, Shugin LIN, Shuyu CHEN, Kaoru SAKAI1991 Volume 40 Issue 1 Pages 39-43
Published: January 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe ppb order of Cr(III) and (VI) in natural water and human urine were determined by graphite furnace AAS after chelate coprecipitation. The following several pairs of metal ions and chelating agents were examined as coprecipitation carriers : Ni-dimethylglyoxime, Co(II)-1-nitroso-2-naphthol, Co(II)-dithizone, Ni(II)-dithizone, Fe(II)-dithizone, Co(II)-pyrrolidinedithiocarbamate (APDC), Zn(II)-APDC, Fe(III)-diethyldithiocarbamate (DDTC), Cu(II)-DDTC and Mn(II)-DDTC. Among these metal chelate carriers, it was found that Mn(II)-DDTC was the most suitable for the separation of Cr(III) and (VI) by selecting suitable pH value. After coprecipitation with Mn(II)DDTC, the graphite furnace AAS was applied to both natural water and human urine samples. In case of natural water, the recovery of Cr(VI) was from 85.4% to 93.6%, and that of Cr(III) was 87.4% to 97.4%. In case of human urine, that of Cr(VI) was from 87.5% to 108.2%, and that of Cr(III) was from 94.4% to 105.3%. The relative standard deviations of the analytical results were as follows. In case of Cr(VI) and (III) in river water, they were 0.88% and 5.52%, respectively, and in case of those in human urine, they were 1.98% and 5.78%, respectively. The proposed method was successfully applied to the determination of trace amounts of Cr(III) and (VI) in natural water and human urine.View full abstractDownload PDF (564K) -
Tokuo SHIMIZU, Masayuki IZAWA, Kenji ICHIKAWA, Yoshio SHIJO1991 Volume 40 Issue 1 Pages 45-47
Published: January 05, 1991
Released on J-STAGE: January 19, 2010
JOURNAL FREE ACCESSA micro-scale technique for the preconcentration of Co at sub-ppb level in natural water samples has been developed. A 10-ml aliquot of filtered sample and 1 ml of pH buffer were added to a mini-column containing 0.25 ml of Unicellex A-100 or B-100. The sample solution was adjusted to pH 4.0. Cobalt was adsorbed on the resin by batch operation (15 min) and then column operation was performed. After the resin was rinsed with water and pH 5.2 buffer, Co was stripped from the resin with 0.2 ml of 2 M hydrochloric acid. The eluate was subjected to Co determination by graphite furnace AAS using a pyrolytic graphite tube. A preconcentration factor of 50 was obtainable using 10 ml of water sample. The lower limit of determination (10σ) was 0.050 μg/l. Relative standard deviations (n = 4), using Unicellex B-100, were 1.0% for 0.97μg/l of Co in river water and 4.5% for 0.22 μg/l of Co in seawater.View full abstractDownload PDF (357K) -
Akiko KATAFUCHI, Toshihiko IMATO, Jun-ichi YAGI, Kozo TAKAHARA, Nobuhi ...1991 Volume 40 Issue 1 Pages 49-52
Published: January 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA flow injection method for rapid and simple determination of saponification value of oils was investigated using neutralization reactions in the nonaqueous solvent system. The flow injection system consisted of three stream channels. A sample solution of an ester (200 μl) was injected into a carrier stream (ethanol) and was merged with an ethanol stream containing 0.1 M tetrabutylammonium hydroxide. Hydrolysis reaction of the ester was completed during flowing through a 50 m reaction coil at 100°C. The resulting stream was subsequently merged with a stream 0.1 M butyric acid-ethanol solution containing 0.1 M lithium chloride and 2 × 10-5 M Methyl Red. The pH or absorbance change of the final mixed stream was measured by two detectors (a glass electrode and/or a spectrophotometer). Absorbance was measured at 490 nm, corresponding to the maximum absorbance of Methyl Red in the acidic form. The changes of the electrode potential and of the absorbance were observed as peak-shaped signals. Peak heights provide concentration of esters. The linear relationship between peak heights and concentrations of lauric acid ethyl ester was observed from 0.02 M to 0.1 M. Other esters of saturated and unsaturated aliphatic carboxylic acids were determined with almost the same sensitivity as lauric acid ethyl ester. The sampling rate and the relative standard deviation were ca. 20 samples/h and 1.3 %, respectively. The proposed method was successfully applied to the determination of saponification value of butter samples.View full abstractDownload PDF (582K) -
Takeshi TSUJI, Tadashi MOCHIZUKI, Hideo SENO, Hideo IWATA1991 Volume 40 Issue 1 Pages 53-56
Published: January 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe metal vapor evaporated from molten steel was solidified to yield fine particles. Using this technique, the resulting particles were introduced into an atomic absorption spectrometric instrument with an electrically heated absorption cell which utilized Ar as the carrier gas. The majorirty of the particles were of round shape and their diameters were less than 1 μm. The temperature of the molten steel and the absorption cell had a great influence on the sensitivity. As the absorption cell temperature increased up to 1200°C, the manganese absorbance became substantially higher. The use of the iron absorbance as the internal standard was effective in correcting the variation in the amount of fine particles introduced into the absorption cell.View full abstractDownload PDF (341K) -
Hiroyasu YOSHIKAWA, Hideo IWATA, Shiro ARIGA, Takamasa TAKAHASHI1991 Volume 40 Issue 1 Pages T1-T4
Published: January 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSTrace amount of sulfur (less than 10 ppm) in high-purity iron was determined by coulometric titration after high-frequency combustion. In order to obtain a reliable analytical value, analytical conditions, such as oxygen flow rate, amount of accelerator and sample, were examined. Recovery of sulfur as sulfur dioxide from steel was almost quantitative for less than 15 ppm sulfur content, but it was 88.7% in the range of 50200 ppm sulfur content. The obtained analytical values were in good agreement with reference values. The detection limit of the present method was 0.23 μg. The precision of the present method was equivalent to that of the Methylene Blue absorption method after nitrobenzene extraction.View full abstractDownload PDF (541K) -
Tomozo KOH, Katsunobu KITAMI, Yasuyuki MIURA, Yasunobu YONEMURA1991 Volume 40 Issue 1 Pages T5-T8
Published: January 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSIodide in various geothermal water samples was determined simply and rapidly with an iodide ion selective electrode. Two procedures were investigated for the determination of iodide. The first method is a direct method in which the iodide content in the geothermal water samples was directly measured with the iodide electrode after the addition of sodium hydrogen sulfite, a definite amount of iodide and ionic strength adjustment buffer. The other is a solvent extraction method in which iodide in the samples oxidized in advance by hydrogen peroxide was extracted into carbon tetrachloride. The iodide backextracted into an aqueous sulfite solution was measured with the iodide electrode. Both procedures were successfully applied to the determination of iodide in the concentration below 1 ppm in various geothermal water samples with a relative standard deviation of 1.8%, and the results obtained by the proposed method were in good agreement with those by the spectrophotometric method using Methylene Blue.View full abstractDownload PDF (509K) -
Teruyuki KITAGAWA, Mitsue HARA, Shizuka YOKOBAYASHI, Tetsuo KAWABATA, ...1991 Volume 40 Issue 1 Pages T9-T13
Published: January 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe analytical conditions for the Karl Fischer (KF) method with water vaporizer were studied as routine analysis of water in drug substances. The effects of desiccants for a carrier gas and the heating temperature upon the blank value were examined. It was found that the volume of KF reagent consumed for a sample titration must be corrected using the blank value obtained in the same titration time in all cases. The standard heating temperature for drug substances was investigated by thermal analysis of various compounds with and without containing crystalline water. As the results, 150°C was suitable as the water vaporizing temperature. But, in some cases it was found to heat "10°C below the decomposition point" should be appropriate. The accuracy and analytical precision of this method was enough high compared with those of the direct KF method. Therefore, this method is considered to be useful as the water determination of drug substances which interfere with KF reagents. It is also usable as a simple test method to confirm data obtained by the direct KF method.View full abstractDownload PDF (637K) -
Yoshihito SUZUKI, Hitoshi KOIZUMI, Kazue TANI, Mingyu DING1991 Volume 40 Issue 1 Pages T15-T19
Published: January 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA chemically bonded hydrophilic anion-exchange column (SAM® column) has been used for the separation of inorganic anions and organic acids using carbonate buffer as an eluent. In this study, the retention behavior of organic acids on the SAM column was investigated using potassium biphthalate eluent with a conductivity detector. This method showed higher sensitivity and good linear range over three orders of magnitude. The regression coefficient (r2) was above 0.997 for each organic acid under tested concentration range. Detection limits for eight organic acids were between 6 and 33 ng. The determination of organic acids in beverages, such as Japanese sake, wine and fruit juices, was carried out by this method with a satisfactory reproducibility.View full abstractDownload PDF (527K) -
Toshikatsu NISHIOKA1991 Volume 40 Issue 1 Pages T21-T23
Published: January 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA characterization method of a polymer-polymer coated interface has been developed using FTIR microspectroscopic functional group imaging. A cross section of a coated sample was prepared as a microtomed cross section perpendicular to the film layers. The coated sample investigated was prepared by coating a polyurethane layer on the ethylene-acrylic acid copolymer/ethylene-ethyl acrylate copolymer. A mixed phase of the two polymers was detected at the interface region; this phase was approximately 70 μm in thickness. A molecular interaction (about 60 μm in depth) was detected between secondary amine groups in the polyurethane and carboxyl groups in the ethylene-acrylic acid copolymer/ethylene-ethyl acrylate copolymer.View full abstractDownload PDF (347K)
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