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Volume 37, Issue 1
Displaying 1-16 of 16 articles from this issue
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Seiji NAKAMURA, Shinichiro KAWAHARA, Makoto HAMADA, Atsuhito MATSUO, K ...1988 Volume 37 Issue 1 Pages 1-6
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSIsotope dilution surface ionization MS has been applied to the accurate determination of Pb in rock standard reference materials. After being spiked with 206Pb, the sample was decomposed in a mixture of HNO3, HClO4 and HF under pressure at 150°C and was evaporated to dryness under nitrogen. The residue obtained was dissolved in a dilute HNO3 solution. Lead was extracted from the solution as its dithizonate into chloroform. An aliquot was applied to the mass spectrometer (Hitachi RMU-6) equipped with a surface ionization device incorporating a Re single filament. Sample preparation was carried out entirely in the Class 100 ultra clean room. By raising the temperature of the ionization filament, the present method could measure the isotopic ratio of spiked lead within precision of 0.5% (relative standard deviation), and could determine trace amounts, i.e., 10-1 pmol of lead within precision of 1%. Prior to the determination of lead concentration, the isotopic abundance of this element in every rock reference material was measured within 0.2% relative standard deviation.View full abstractDownload PDF (1115K) -
Chushiro YONEZAWA, Michio HOSHI, Enzo TACHIKAWA, Hiroshi KAMIOKI1988 Volume 37 Issue 1 Pages 7-11
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA method has been established for the determination of ultra trace ppb levels of U and Th in semiconductor memory materials by radiochemical neutron activation analysis (RNAA) using thenoyltrifluoroacetone (TTA) liquid-liquid extraction. Samples, (50100mg) together with standard solutions, were irradiated in JRR-2 or JRR-4 at a thermal neutron flux of (5.58)×1013n cm-2 s-1 for 0.17 to 6.0h. After cooling for more than 1d, the samples were finally dissolved with 1M hydrochloric acid. Neptunium-239(IV) and 233Pa (V) were extracted from the solution in the presence of ferrous chloride with a 0.5M TTA-xylene. The 232Np and 233Pa were back extracted with 10 M nitric acid and 5M sulfuric acid, successively, and their gamma-ray spectra were measured with a Ge (Li) detector. Similar procedures were also applied to the standard solutions. The U and Th contents were calculated from the peak areas of gamma-rays of 228.2 and 277.6keV for 239Np and 312.0keV for 233Pa. Accuracy of the present method was confirmed by satisfactory agreement between the experimental results and the concensus average values of reference rock samples (JB-1, JG-1). The method was applied to the determination of more than 0.5ppb of U and Th in Al, Mg and MgO.View full abstractDownload PDF (1010K) -
Tadashi MOCHIZUKI, Akiko SAKASHITA, Hideo SENO, Hideo IWATA1988 Volume 37 Issue 1 Pages 12-16
Published: January 05, 1988
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSAn ICP-AES method has been developed for the rapid analysis of slag samples. The ruby laser is used for ablating the solids and the aerosols produced are directly introduced into the plasma by flow of Ar carrier gas. Slag powders are pelletized into a Cu-ring(Briquet method) or are fused with Na2B4O7 (Bead method) to obtain sample discs. These procedures have been applied to domestic standards of slag samples. The bead method yields better accuracy and precision for most analytes such as Si, Al, Mg, Fe and Mn, but trace elements can be determined by means of the briquet method with improved accuracy and precision.View full abstractDownload PDF (859K) -
Yuji FUJIOKA, Masahiko TSUCHIYA1988 Volume 37 Issue 1 Pages 17-24
Published: January 05, 1988
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSPolycyclic aromatic hydrocarbons (PAH) in coal tar pitches were measured by liquid ionization (LI) MS. It is important to know the molecular weight distribution of components in coal tar pitches in order to understand their chemical properties as industrial raw materials. The LI method provides protonated molecules (MH+) of PAH compounds, showing a mass spectrum similar to its field desorption (FD) spectrum, the latter generating M+ ions. The MH+ ion peak of each PAH component in the pitch was observed at its optimum temperature which is high for larger molecular weight component. The molecular weight distribution of the main volatile PAHs (molecular weights are less than 350) calculated from the LI spectra was in good agreement with that calculated. from the corresponding chromatographic peaks measured by GC/MS. In addition, PAHs whose molecular weights were larger than 350 were also measured easily by the LI method. Analysis of fractions extracted from the pitch using several solvents provided detailed information about the high molecular weight PAHs. Molecular weight distribution and average molecular weight calculated from the LI spectra were similar to those obtained by the FD method. The LI method is useful for analysing coal tar pitches, because it provides stable and reproducible mass spectra by a simple and rapid analytical procedure.View full abstractDownload PDF (1051K) -
Koichi ITO, Shigeru KUBOYAMA, Hiroshi OGURO, Takako KAGAYA, Tadashi SH ...1988 Volume 37 Issue 1 Pages 25-29
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA sensitive and rapid method for the U and Th in Au by inductively coupled plasma ion source mass spectrometry (ICP-MS) have been investigated. The detection limit for U and Th in an aqueous solution were 8.0×10-4 and 1.2×10-3ng/ml, respectively. A linear relationship was found in a dynamic range between 10-2 to 103ng/ml. Gold dissolved in aqua regia showed mass spectral interferences consisting of molecular ion peak of 197Au35Cl+ superimposed on that of 232Th+ having the highest isotopic abundance. This was found disadvantageous for the determination of Th, and moreover, a decrease of U ion counting sensitivity was observed for Au concentration of more than 0.1%. In order to alleviate these effects, the separations of U and Th from the Au matrix were undertaken by using anion exchange resin. Gold was dissolved in aqua regia and chloroauric acid crystals which were obtained by gentle evaporation, were dissolved in 0.5M hydrochloric acid. This solution was passed through an anion exchange resin filled column, and the elute analyzed by ICP-MS. The recovery percentage of better than 93% for both U and Th were attained, and the relative standard deviations for the repeat analyses of these elements were 12 and 14% respectively, figures which are considered practically satisfactory for this ultra trace element determination. Thus, with this method, determination of U and Th of several ppb in Au became possible.View full abstractDownload PDF (933K) -
Makoto NAGASE1988 Volume 37 Issue 1 Pages 30-34
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA simple method for the determination of sulfite in foods has been developed by ion chromatography after purge-and-trap. After 0.21.0g of sample was placed in a SO2 generator with 20ml of distilled water, 2ml of ethanol and 10ml of 25% H3PO4 were added. SO2 produced from sulfite by heating was purged with nitrogen at 500ml/min for 10min and absorbed into 10ml of 0.1M NaOH cooled with ice and water. After this solution was made up to 25ml with distilled water, sulfite ion was determined by ion chromatography. The condition was as follows: Column, HPIC-AG3 (50mm×4mm i.d.)+HPIC-AS3 (250mm×4mm i.d.) (Dionex); suppressor, anion fiber suppressor; eluent, 6mM NaHCO3-4.8mM NaCO3 (1:1); flow rate, 1.1ml/min; column temp., room temp.; detection, conductivity 3μS/cm full scale; sample injection volume, 100μl. The calibration curve was made by adding standard sulfite solution (NaHSO3 aqueous solution) to 20ml of distilled water. The calibration curve was linear for 390μg SO2 added. Recoveries of SO2 added to 9 kinds of foods at the level of 301000μg/g were 72.7103%. The limit of detection was 3μg/g for 1g of sample.View full abstractDownload PDF (834K) -
Hiroshi NAKAMURA, Zenzo TAMURA1988 Volume 37 Issue 1 Pages 35-40
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA method for the fluorometric determination of thiols and disulfides in rat plasma and various organs by HPLC has been developed. The heart blood and organs were taken from Wistar rats (male, ca. 210g) anesthetized with diethyl ether. After addition of homocystine as an internal standard, the plasma or tissue homogenate was deproteinized in 400500mM perchloric acid by centrifuging at 1600×g for 5min. The pH of the resultant supernatant was adjusted to 3 by the addition of 3M potassium bicarbonate and similarly centrifuged. The aliquot (550μl) of the supernatant was subjected to cation exchange HPLC with postcolumn derivatization. Thiols and disulfides were separated on a column of Partisil-10 SCX (4.6mm i.d.×25cm) with gradient elution, reacted with sodium sulfite to cleave disulfide bonds at pH 67 and the orthophthalaldehyde-taurine reagent at pH 9.410.5 to produce isoindole fluorophores, and monitored with a fluorescence detector (λex 358nm; λem 460nm). The method was successfully applied to the analyses of rat plasma, liver, kidney, spleen and brain for thiols and disulfides.View full abstractDownload PDF (995K) -
Haruki SHIRAISHI, Reiji TAKAHASHI1988 Volume 37 Issue 1 Pages 41-46
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSIt was found that the preelectrolysis in the solution containing purine derivatives and Cu (II) at glassy carbon electrode (GCE), potentiostated at ca. 0V (vs. SCE), caused the oxidation peak current of purine derivatives increase by 1020 times. This effect enables the voltammetric determination of purine derivatives of 10-6M concentration level. The purine derivatives which showed this effect were hypoxanthine, xanthine, uric acid and the substituted adenine and guanine by methyl group at 1- or 7-position. But 3- or 9-methyl substituent of adenine and guanine hindered this phenomenon. The increase of oxidation peaks was explained as that the copper adducts of purine derivatives were deposited on GCE by preelectrolysis, and the dissolution of the adduct at anodic scanning increased the concentration of purine derivatives in the immediate neighborhood of the electrode.View full abstractDownload PDF (1014K) -
Masashi GOTO, Shigeo MUROFUSHI, Daido ISHII1988 Volume 37 Issue 1 Pages 47-51
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA continuous monitoring method was developed for the automatic determination of total nitrogen in wastewater based on "the continuous micro flow analysis", in which a sample is continuously injected into the continuous flow of reagents. A sample and a solution of 0.60M sodium hydroxide containing 1.8% potassium peroxodisulfate are continuously pumped with a peristaltic pump at the flow rates of 100 and 50μl/min, respectively and they are mixed with each other in a mixing joint. The mixture is introduced into a reaction tube made of Teflon tubing (0.50mm inner diameter, 8m length) in an aluminium block bath of 150°C, in which the sample is decomposed by oxidation reaction. A platinum wire of 0.20mm in diameter is inserted into the reaction tube to serve as a catalyst for the oxidation reaction. All nitrogen compounds such as ammonium, nitrite, nitrate and organic nitrogen are converted to the nitrate ion in the reaction tube. The stream from the reaction tube is mixed with a stream of 0.62M hydrochloric acid at a flow rate of 50μl/min to neutralize and is then introduced into a flow cell of a UV photometer. The absorbance at 220nm based on the nitrate ion is continuously recorded, thus the total nitrogen in sample is automatically measured. The method was successfully applied to continuous monitoring of total nitrogen in wastewater from chemical laboratories.View full abstractDownload PDF (948K) -
Continuous monitoring method of total phosphorus in wastewater using continuous micro flow analysis.Masashi GOTO, Masato NISHIMURA, Takayuki TOMINAGA, Daido ISHII1988 Volume 37 Issue 1 Pages 52-55
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA continuous monitoring method was developed for the automatic determination of total phosphorus in wastewater based on absorption spectrophotometry with phosphomolybdate and Malachite Green. The sample, a peroxodisulfate solution containing dilute sulfuric acid and a mixed solution of molybdate and Malachite Green is continuously pumped with a peristaltic pump at a flow rate of ca. 60μl/min. The sample is, first, mixed with the oxidizing and hydrolyzing reagent in a mixing joint and then introduced into a reaction tube made of Teflon tubing (0.64mm inner diameter, 4m length) in an aluminium block bath of 120°C, in which the sample is decomposed by oxidation and hydrolysis reaction. A platinum wire with a diameter of 0.2mm is inserted into the reaction tube to serve as a catalyst for the oxidation reaction. All of the condensed phosphate and organic phosphorus compounds are converted to the orthophosphate ion in the reaction tube. The stream from the reaction tube is mixed with a stream of a coloring reagent to form an ion associate of phosphomolybdate-Malachite Green, which is then introduced into a flow cell of a visible photometer. The absorbance at 600nm based on the ion associate is continuously recorded, thus the total nitrogen in sample is automatically measured. The method was successfully applied to continuous monitoring of total phosphorus in wastewater from chemical laboratories.View full abstractDownload PDF (826K) -
Kazuyoshi FUJIMURA, Masahiko TSUCHIYA1988 Volume 37 Issue 1 Pages 56-59
Published: January 05, 1988
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSPreservatives in soft drinks and wines were determined by ion chromatography using a Toyo Soda IC-Anion-PW column. Three UV detectors in series were used at wavelengths of 225, 254 and 272nm for qualitative information, respectively. The effect of pH, ion concentration of sulfamic acid and concentration of organic solvent on retention times of organic acids were investigated to determine optimum conditions for benzoic, sorbic, dehydroacetic, and 4-hydroxybenzoic acids. Benzoic acid and sorbic acid in soft drinks and wines were satisfactorily determined with 6mM sulfamic acid as an eluent.View full abstractDownload PDF (693K) -
Kazuyoshi FUJIMURA, Masahiko TSUCHIYA1988 Volume 37 Issue 1 Pages 59-63
Published: January 05, 1988
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA method for determining nitrogen oxides and sulfur oxides by ion chromatography was investigated in order to develop a method for eliminating nitrogen oxides and sulfuric oxides in stack gas using nitrate melts. A Toyo Soda IC-Anion-PW column, an electrical conductivity detector and a UV detector were used. The effect of pH and concentrations of phosphoric acid and gluconic-Borax complex on retention times were investigated for nitrite, nitrate, sulfite and sulfate ions in an aqueous solution. A solution containing 0.7mM potassium gluconate, 0.7mM Borax, 0.1mM potassium dihydrogen phosphate and EDTA (1.5mM/l) adjusted to pH 7.4 with boric acid was found to be an optimum eluent. Nitrous acid, sulfurous acid and sulfuric acid in nitrate melts containing abundant ions of nitric acid were determined by this method.View full abstractDownload PDF (965K) -
Masami MATSUI, Takaharu KITSUWA1988 Volume 37 Issue 1 Pages 63-65
Published: January 05, 1988
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSTo achieve rapid determination of dicarboxylic acids and hydroxy fatty acids as their underivatized forms, GC conditions including column packing material were examined. As the result, an OV-17 liquid phase coated on Tenax GC was found to give well defined, sharp and symmetrical peaks for dicarboxylic and hydroxy fatty acids. This column gave good separation for lactic, glutaric, adipic, pimeric, suberic, azelaic, sebacic and undecanedioic acids. The relative standard deviations (n=5) for the determination of dicarboxylic and hydroxy fatty acids (lactic acid, hydroxy myristic acid, hydroxy palmitic acid, hydroxy stearic acid) were less than 5.0%. As an exception, maleic and succinic acids were determined as their anhydrides after dehydrogenation by phosphoric acid retained on silica wool in the injection port.View full abstractDownload PDF (588K) -
Jun-ichi ITOH, Masashi KOMATA, Hiroshi OKA1988 Volume 37 Issue 1 Pages T1-T4
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSComplex formation reaction of a water soluble porphyrin, α, β, γ, δ-tetrakis (4-N-trimethylaminophenyl) porphine (ttmapp), with Cu(II) is studied. Although the reaction rate was very slow at room temperature, it was greatly accelerated to form Cu(II)-ttmapp complex in the presence of sodium L-ascorbate. When the sodium L-ascorbate concentration was over 10-4%, the reaction proceeded quantitatively at a pH range of 4.15.9 within 5min at room temperature. The complex was stable between pH 013. The absorption maxima, λ (and the molar absorptivities, ε) of the Soret bands of ttmapp and the Cu(II) complex at pH 1.2 were 432nm (ε=5.14×105) and 411nm (ε=5.07×105), respectively. The recommended procedure is as follows. To a sample solution containing Cu(II) 02.5μg in a 25-ml measuring flask, add 0.5ml of 2M acetate buffer solution (pH=5), 0.5ml of 0.05% sodium L-ascorbate solution and 0.5ml of 9×10-5M ttmapp solution. After standing for 5 min at room temperature, add 2.5ml of 5M nitric acid to the solution followed by dilution to 25ml. Measure the absorbance at 432nm against water with 1-cm cells. Tolerance limits were shown for 27 metal ions and 6 anions. A linear calibration curve was obtained up to 100ppb of Cu(II) and the sensitivity (Sandell index) was 0.122ng Cu (II) cm-2. The relative standerd deviation was 1.3% (n=10). The present method could be applied to the determination of Cu in tap water with satisfactory results.View full abstractDownload PDF (830K) -
Gas electrode detector for gas chromatography. IIYoshimitsu SEO1988 Volume 37 Issue 1 Pages T5-T10
Published: January 05, 1988
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA gas electrode detector was developed by combining a newly developed ammonia gas sensor with a chromatography data system made in my laboratory. This sensitive and selective gas sensor is constructed of a commercially available cation-sensitive glass electrode. Compounds eluted from a GC capillary column, using hydrogen as carrier gas, are passed through a silica tube (30cm×0.5mm i.d.) packed with nickel wires (6cm×0.3mm) and heated at 820°C. By this treatment, nitrogen compounds can be converted to ammonia and hydrocarbon compounds, to methane. The decomposition gases are blown upon a hand-twisted cotton thread which is tangential to the sensitive surface of the micro cationic electrode. Through the cotton thread, 0.1M tris(hydroxymethyl)aminomethane buffer of pH 8.5 flows (5 μl/min), where the ammonia is trapped by the tris buffer. The potentiometric output is digitized and transferred to the microcomputer system (CPU 6502C) equipped with a hand-made arithmetic processing unit (Am9511A) card. All programs are written in BASIC except an assembly language subroutine, in which data is obtained by averaging over sampling period (0.10.4 s). This compiled BASIC program is run for less than 15s. The response of the detector is directly proportional to the number of nitrogen in the particular molecule(CH3NO2) and was about 50times as high as that of FID.View full abstractDownload PDF (964K) -
Motonori ETOH1988 Volume 37 Issue 1 Pages T11-T15
Published: January 05, 1988
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe determination of Pt, Pd and Rh in silica-alumina based catalyst by ICP-AES was investigated. Samples were decomposed with aqua regia (1+1) in a Teflonlined bomb. All samples used in this experiment were completely decomposed by the proposed conditions. Aluminum greatly affected the determination of Pt metals by ICP-AES, such that Pt metals were separated from the carrier constituents by precipitating them with 2-mercaptobenzothiazole (MBT). Platinum, palladium and rhodium were quantitatively precipitated with MBT by the addition of stannous chloride. The precipitate was decomposed by heating with nitric, perchloric and sulfuric acids, then Pt, Pd and Rh were determined by ICP-AES with Y as an internal standard which was used for the improvement of precision and to eliminate the effect of acid concentration. At the separation with MBT, Cu was quantitatively coprecipitated with Pt metals and Sn was also contained in the precipitate. However, up to a hundred times the concentration of Cu and Sn could be tolerated by ICP-AES. This method was applied to the analysis of silica-alumina based catalyst. The recoveries of this method were in good agreement with those by the coprecipitation method with Te. Relative standard deviations of five replicate analyses of this method were 0.20.7%.View full abstractDownload PDF (1011K)
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