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Volume 40, Issue 7
Displaying 1-12 of 12 articles from this issue
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Sorin KIHARA, Zenko YOSHIDA, Hisao AOYAGI1991 Volume 40 Issue 7 Pages 309-323
Published: July 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe overall feature of the oxidation-reduction behavior of U, Np or Pu ions in acidic aqueous media has been elucidated based on the results of the electrolysis at a column electrode with the following advantages 1) coulometric electrolysis can be attained extremely rapidly, 2) quantitative electrolysis proceeds with considerably small overpotential even if the electrode reaction is totally irreversible, and 3) the electrolysis is carried out in a flow-system. These advantages are favorable to the preparation of unstable species such as Np3+, Pu3+ or PuO2+ for the subsequent investigation of their chemical behavior. A detailed discussion was made on the irreversible electrode reduction of AnO2+and the oxidation of An4+(An : U, Np or Pu). PuO2+An02was found as an intermediate species in the reduction of PuO2+. Based on the above fundamental results, rapid methods were developed for the coulometric determination of Pu, and for the speciation of Np or U and Pu in their mixtures. A chemical method was also proposed for the analysis of the oxidation state of U in UO2 pellets employing dissolution with strong phosphoric acid followed by detection using the column electrode. The reduction product of UO22+ in weakly acidic media, U4+, was found to be deposited on the glassy carbon electrode as a hydroxide or an oxide. This phenomenon was utilized for the collection and determination of trace U by column electrolysis.View full abstractDownload PDF (2556K) -
Manabu FUJIWARA, Takayuki MATSUSHITA, Yuko YAMASHOJI, Toru MORITA, Sei ...1991 Volume 40 Issue 7 Pages 325-330
Published: July 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSNovel tetraaza macrocyclic Schiff base ligands (L1 and L2) having a chromophore have been synthesized by reaction of 7-chloro-4-nitrobenzoxadiazole with the parent macrocyclic ligands, 5, 7, 12, 14-tetramethy1-1, 4, 8, 11-tetraazacyclotetradeca-1, 5, 7, 12-tetraene and 6, 8, 15, 17-tetramethyl-dibenzo-5, 9, 14, 18-tetraazacyclotetradecene, respectively. These ligands have been found to complex selectively with a copper(II) ion. Under optimal complexation conditions, L1 afforded a higher molar extinction coefficient (logε=4.22) than L2, so that L1 has been applied to a spectrophotometric reagent for the determination of copper(II) ion by FIA. Two systems, a parallel flow method and a merging zone method, have been examined and the latter has been found to be superior to the former. This is due to that the complexation is less complete in the former than in the latter case. Although the sensitivity to the copper(II) ion obtained under the optimal conditions is comparable to that obtained in a batch system, the method exhibits advantages such as less interference from nickel(II) ion during the determination and shortening of the time required for the determination.View full abstractDownload PDF (941K) -
Tsuneaki MAEDA, Emiko OKAMOTO, Kouji ICHIOKA, Masatoshi MORITA1991 Volume 40 Issue 7 Pages 331-336
Published: July 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSAn automated monitoring system to measure sub ppb level of CFC 11, CFC 113, dichloromethane, carbontetrachloride, 1, 1, 1-trichloroethane, chloroform, trichloroethylene, tetrachloroethylene was developed by using GC with preconcentration on porous polymer beads and an electrolytic conductivity detector (HECD) was used for detection. Air sample was passed through a trap column where volatile halogenated hydrocarbons were trapped at cooled temperature and thermally desorbed. They were then introduced into the GC system using a sequence of every 70 min. Separation of individual compounds was made by using a series of packed columns of Ucon 50 LB 550X and Octane/Porasil C at programmed temperature conditions. Measured data were stored in the memory of integrator and printed out either simultaneously or later time. Recovery of the com-pounds was almost quantitative and the practical detection limits were about 0.1 ppb for 2 1 sample.View full abstractDownload PDF (727K) -
Shinkichi YAMADA, Kazutoshi BAN, Akira MURATA1991 Volume 40 Issue 7 Pages 337-342
Published: July 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSKinetics of the oxidation of hydroxycoumarins with periodate was studied fluorometrically in acetate buffer. Among the nine coumarins studied, only the o-dihydroxy derivatives were oxidized by periodate to give yellow-colored nonfluorescent product. The reaction was catalytically accelerated by trace amount of metal ion. In the presence of copper(II) ion, the rate law for the oxidation of 4-methyl-6, 7-dihydroxycoumarin (S) with sodium periodate can be expressed as -d[S]/dt=k1×[S][IO4-]+k2[S][IO4-]/[H+] +k3[S][IO4-][Cu2+]/[H+]. The catalytic capacity of metal ion was reflected in the value of k3. The linear relationship between the logarithmic values of k3 and the formation constant of 1:1 pyrocatecholate complex suggests that reaction involves a preequilibrium where a reactive complex is formed between metal ion and the coumarin. Employing this reaction system, copper(II) can be catalytically determined up to 65 ng/ml with the detection limit of 0.8 ng/ml.View full abstractDownload PDF (833K) -
Chiyo MATSUBARA, Kazuaki SAKAI, Kiyoko TAKAMURA1991 Volume 40 Issue 7 Pages 343-347
Published: July 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA sensitive and selective FIA using the Ti-PAR {4-(2-pyridylazo)resorcinol} reagent was developed for the determination of oxalate in urine. Flow injection manifold was composed of a three-channel system with immobilized oxalate oxidase and ion-exchange columns. All of the solution were pumped at a flow rate of 0.3 ml/min. The sample solution (5 μl) was injected into a sample carrier stream and passed through the oxalate oxidase column, which converted the oxalate to hydrogen peroxide. The produced hydrogen peroxide was then monitored by measuring the absorbance (508 nm) of the Ti(IV)-PAR-H2O2 complex formed with the Ti-PAR reagent. The results were not affected by the presence of metallic ions, such as Fe3+and Ca2+and reducible substances in urine. The responses were linear between 2×10-6 and 1×10-3M oxalate, and the relative standard deviation was1.0% (n=10) at4×10-5 M (200pmol/injection). The throughput rate was 40 samples/h.View full abstractDownload PDF (800K) -
Toshio YOKOYAMA, Toshio KINOSHITA1991 Volume 40 Issue 7 Pages 349-353
Published: July 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA method is described for the simultaneous determination of allantoin (Alt) and taurine (Tau) in pharmaceutical preparations by postcolumn HPLC using thiamine reagent on Ionpak®KC-811 column. The effluent from the column was mixed with the hypochlorite reagent and passed through a coil (3 m×0.5 mm PTFE) at ambient temperature to convert Alt and Tau into the corresponding N-chloramines. The eluent was then mixed with the thiamine reagent and passed through another coil (5 m × 0.5 mm PTFE) at 60°C to give highly fluorescent thiochrome. The fluorescence intensity was measured at the wavelengths of Ex. 370 nm and Em. 420 nm. The hypochlorite reagent was a sodium hypochlorite solution in 0.1 M phosphate buffer (pH 7.5) containing 0.05% available chlorine and 60 mM NaOH. The thiamine reagent was 0.02% thiamine hydrochloride solution in 0.1 M phosphate buffer (pH 7.5) containing 1% NaNO2. A linear relationship was observed between the peak height and amount of Alt or Tau injected in the range 20 ng-2μg, respectively. The present method was applied to the assay of Tau and Alt in various preparations. The average recovery of spiked Tau and Alt from eye lotions was 100.8±1.4 % (n=6) and 99.8±1.2 %(n=6), respectively.View full abstractDownload PDF (628K) -
Shoji MOTOMIZU, Mitsuko OSHIMA, Takashi HIRONAKA1991 Volume 40 Issue 7 Pages 355-360
Published: July 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSIon chromatography by indirect photometric detection was studied with 1, 5-naphthalenedisulfonate (1, 5-NDS) as an eluent ion. The advantages of 1, 5-NDS are: (1) UV light absorption at longer wavelength near 300 nm, (2) adequate strength of elution ability for analysis of environmental waters, (3) little interference from pH change, and (4) stable, low cost and commercially available reagent. Chloride, nitrate and sulfate ions in river, spring and tap waters were determined with 4× 10-4M 1, 5-NDS by injecting 20 μl of sample solution. By injecting 100 μl of sample solution, these anions in rain water were determined with 2× 10-4 M eluent. When Ca2+ and Mg2+ coexist at concentrations above 10-3 M, pretreatment with cartridge-type cation exchanger column is useful. Calcium(II) and manganese(II) ions were simultaneously determined with the other anions using the eluent containing 1 × 10-4 M 1, 5-NDS, 5× 10-5 M EDTA and 1 × 10-4 M acetate buffer solution (pH 6).View full abstractDownload PDF (905K) -
Yoshihito IWATA, Youichi ISHIBASI, Naoki GUNJI, Hiroyasu YOSHIKAWA1991 Volume 40 Issue 7 Pages 361-364
Published: July 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSTrace amounts of Fe, Cu and Ni in titanium alloy were quantitatively coprecipitated with indium hydroxide after masking titanium. A 200 mg amount of the sample was dissolved in hydrochloric acid. Before the coprecipitation procedure, the resulting titanium ions were masked with hydrogen peroxide to form its peroxo-complex. At least 3 cm3 of hydrogen peroxide was required for masking the titanium ions. Indium (11 mg) was added and the pH was adjusted to 9.0 using sodium hydroxide. Recovery of trace elements were optimum at pH 9.0. The precipitate was obtained by using a membrane filter system. The membrane filter was pressed between polyethylene phthalate film. It was then dried and measured directly by XRF. Detection limits were as follows: Fe 8.1 μg/g, Cu 0.8 μg/g, and Ni 1.4 μg/g in titanium alloy.View full abstractDownload PDF (456K) -
Michio ZENKI, Jun INEYAMA, Junko WATANABE, Youko UYAMA, Kyoji TÔ ...1991 Volume 40 Issue 7 Pages 365-367
Published: July 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSFour 2-hydroxyazomethine derivatives which have a sulfo and hydroxy groups in benzene rings have been synthesized to give higher water solubility and fluorometric sensitivity. Using FIA, their fluorescence properties were investigated. Since HSCS (the title compound) was found to be most sensitive it was used as a fluorometric reagent for aluminium. A dual channel FIA apparatus was used. An aliquot sample solution (80 μl) was injected into a carrier stream (distilled water) and was merged with a reagent stream containing 0.2% HSCS and 0.1 M acetate buffer (pH 6.0). The wavelength of the fluorometric spectrophotometer were set at Ex 420 nm and Em 505 nm. The calibration curve was linear over the range of 5 to 100 ng/ml of Al. The detection limit was 0.5 ng/ml (S/N = 2). The relative standard deviations for 20 (n = 5) and 100 (n = 5) ng/ml of Al were 0.45 and 0.94%, respectively. Ga(III), Sc(III), Fe(III), Si(IV), Ca(II) and fluoride interfered with the determination.View full abstractDownload PDF (505K) -
Toshikatsu NISHIOKA, Norio TERAMAE1991 Volume 40 Issue 7 Pages 369-371
Published: July 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA simple method was proposed for removal of interference fringes in an IR spectrum. The method was particularly effective for microscopic measurements. The films of polyethylene, approximately 15 μm in thickness, were prepared by pressing the films (30 μgm in thickness) at 190°C for 3 min using an Al-foil with rough surface as a spacer. When the roughness of the polyethylene film surface was below 0.1 μm, interference fringes appeared in the microtransmission infrared spectrum. However, when the roughness of the polyethylene film surface was 0.6 to 1.7 μm, interference fringes were able to be removed. This technique was applied to qualitative analysis of contaminant in a polyethylene film.View full abstractDownload PDF (2291K) -
Kanji NAGAI, Yukikazu HATTORI, Koji TAKAHASHI, Masao NAKAMOTO1991 Volume 40 Issue 7 Pages T137-T143
Published: July 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSVarious kinds of volatile halogenated hydrocarbons (VHH) in water samples were determined using capillary GC/MS connected with an automatic purge and trap concentrator (A.P.T.C.). Optimun operating conditions of A.P.T.C. were studied. The peaks corresponding to the compounds were well separated on the chromatogram. Relative standard deviations (R.S.D.) of response (peak area) and retention time (tR) were 1.9-10.4% and 0.02-0.04%, respectively. The linear ranges of response were about 0.25-2500 ng. This analytical method was successfully applied to the determination of VHH in river and ground water.View full abstractDownload PDF (889K) -
Eiko NAKAMURA, Keiko FUJITA, Akihiko HASEGAWA, Hiroshi NAMIKI1991 Volume 40 Issue 7 Pages T145-T149
Published: July 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSMetal ions such as silver, copper, lead, nickel, cobalt, cadmium and iron in the weak acidic or neutral solution were reduced to the metallic state with sodium tetrahydroborate. The reduced metals were easily separated from the solution by filtration using membrane filter. The adjustment of the pH and the addition of the complexing reagent enabled the selective deposition of metals. In the presence of citrate buffer (pH 10), only copper was deposited from the solution containing copper, lead and iron ions. Silver and copper were deposited even in the presence of EDTA. But, some metal ions such as chromium, zinc, manganese and tin were not deposited from any solution. Nitrate ion interfered the deposition of metals. The proposed method was applied to the analysis of the copper alloy. Phosphor bronze or brass was dissolved with hydrochloric acid and hydrogen peroxide, and the solutions were neutralized with ammonia. A tablet form of sodium tetrahydroborate (0.3 g) was added. After the deposited copper was filtrated, phosphorus and zinc in the filtrate were determined by the Molybdenum Blue method and by EDTA titration, respectively. Copper on the filter was dissolved with nitric acid and then determined by EDTA titration. These results agreed with the results obtained using the JIS method.View full abstractDownload PDF (868K)
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