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Volume 41, Issue 5
Displaying 1-10 of 10 articles from this issue
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Shigeki DAISHIMA, Yoshio IIDA1992 Volume 41 Issue 5 Pages 207-213
Published: May 05, 1992
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSChemical ionization mass spectrometry using Townsend discharge was applied to direct monitoring of trace amounts of organic compounds in air. In the system, one end of an inactivated capillary tube was directly connected to an ion source and the other end was exposed to atmosphere. Thus, the sample air was spontaneously drawn in the mass spectrometer to obtain suitable pressure for reagent gas inside the ion source. Volatile organic compounds in air were effectively ionized by the reactant ions produced from the air itself or methane/air mixture using Townsend discharge. Benzene, toluene, xylenes and chlorocarbons in indoor and outdoor air sampled in Tedlar bag were determined with sensitivity of ppb level. 1, 1, 1-Trichloroethane and tetrachloroethylene contained in the air on the surface of the spot coated with a correction fluid on a paper and in a sweater after dry-cleaning were monitored respectively using a bell-shape sampling probe. The concentrations of them were still ppb level after 24 h. Nicotine in cigarette smoke and Flons sprayed in indoor air were also monitored continuously.View full abstractDownload PDF (738K) -
Chiyo MATSUBARA, Naoki KAWAMOTO, Kiyoko TAKAMURA1992 Volume 41 Issue 5 Pages 215-219
Published: May 05, 1992
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESS[5, 10, 15, 20-Tetra(4-pyridyl)porphinato]oxotitanium(IV){denoted as TiO(tpypH4)4+ (λmax: 432 nm) } reacts with hydrogen peroxide to form a mono-peroxo complex, resulting in a significant decrease of the absorbance at 432 nm. The degree of the absorbance change (Δ Absorbance) was found to be proportional to the concentration of added hydrogen peroxide. This fact was successfully applied to the determination of the glucose in serum and urine by the use of glucose oxidase. A linear relation was obtained between ΔAbsorbance and glucose concentration ranging from 20 nM to 3.2μM (r=0.999). The apparent molar absorptivity of glucose was 1.8×105 M-1 cm-1. The relative standard deviation of repeated runs (1 μM, n=8) was 1.4%. With only 1 μl serum, the content of glucose ranging from 64.8 to 249.1 mg/dl in concentration could be determined. The recovery of glucose (180.2 mg/dl) added to serum was 98.0 to 105.3%. No preconcentration was required to determine glucose in urine (6.5490.8 mg/dl) by the present method because of its high sensitivity for hydrogen peroxide.View full abstractDownload PDF (621K) -
Takashi WATANABE1992 Volume 41 Issue 5 Pages 221-229
Published: May 05, 1992
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSFifteen pesticides from the atmosphere were measured by using 10 solid adsorbents. The trapping efficiencies of Chromosorb 102, SEP-PAK SILICA cartridge and silica gel were higher than other adsorbents, which were over 90% average. As SEP-PAK SILICA cartridge was easy to handle particularly, stabilities and breakthrough of pesticides on SEP-PAK SILICA cartridge were measured. Fourteen pesticides except for dichlorvos were stable on SEP-PAK SILICA at 5°C for 1 day, and 13 pesticides except for dichlorvos and edifenphos were stable at 5°C for 7 days. But dichlorvos was stable only below -15°C. They showed no sign of breakthrough. The detection limit of the pesticides in the atmosphere was 50 ng/m3 for 100 l of air. As the lot of pesticides have vapor pressures ranging from 0.05 to 500 mPa as well as the tested pesticides except for dichlorvos, this method may be available for the trapping of various pesticides in the atmosphere by using SEP-PAK SILICA cartridge.View full abstractDownload PDF (907K) -
Takashi MASADOME, Ji-guang YANG, Toshihiko IMATO, Nobuhiko ISHIBASHI1992 Volume 41 Issue 5 Pages 231-237
Published: May 05, 1992
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe potential response of an electrode, based on an o-nitrophenyl octyl ether (o-NPOE)-plasticized PVC membrane without added ion exchanger, to alkyl sulfate, alkanesulfonate, alkylcarboxylate ions and to several hydrophobic anions was investigated. The electrode exhibits the Nernstian response to alkyl sulfate ions having more than ten carbon atoms in alkyl chains. For alkanesulfonate ions, the electrode shows the Nernstian response to dodecylbenzensulfonate and di-2-ethylhexylsulfosuccinate ions, but does not to ions with less than eleven carbon atoms in alkyl chains. For alkylcarboxylate ions with seven to eleven carbon atoms in alkyl chains, the electrode does not show the Nernstian response, but does to tetraphenylborate and 8-anilino-1-naphthalenesulfonate ions. In order to correlate the response characteristics of the o-NPOE-plasticized PVC membrane electrode to the anionic entities with the hydrophobicity of the ions, the selectivity coefficients of an electrode based on an o-NPOE-plasticized PVC membrane containing trioctylmethylammonium chloride as an ion-exchanger was measured, because hydrophobicity of ions is related to the partition properties of ions between an aqueous solution and the electrode membrane. As a result, the o-NPOE-plasticized PVC membrane electrode was found to show the Nernstian response to hydrophobic anions with a selectivity coefficient of more than 105.5. The potential response of the electrode, based on the PVC membrane plasticized with o-NPOE derivatives, to dodecyl sulfate ion was also investigated. The best plasticizer among o-nitrophenyl phenyl ether and o-nitrophenyl alkyl ethers (C8, C10, C12 and C14) for the dodecylsulfate ion-selective electrode in terms of linear response range and sensitivity was o-NPOE.View full abstractDownload PDF (893K) -
Eiko NAKAMURA, Tamio SAITO, Hiroshi NAMIKI1992 Volume 41 Issue 5 Pages 239-241
Published: May 05, 1992
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSNitrate can be reduced to ammonium ion with sodium tetrahydroborate in the presence of nickel ion and determined by the indophenol method. Fifty milliliters of solution containing nitrate is taken into a 200 ml triangular flask. After the addition of a tablet of sodium tetrahydroborate (0.3 g) and 2 ml of nickel chloride solution (10 mgNi/ml), the solution is strirred for 60 min at 45°C. The deposited nickel is removed with a membrane filter. The filtrate is made up to 100 ml with water and ammonium ion is determined by the indophenol method. To determine total nitrogen in water samples, this method was applied to nitrate produced by the alkaline peroxodisulfate digestion. The results obtained by this method were in good agreement with those obtained by the cadmium-column method for the determination of total nitrogen in sea and river water.View full abstractDownload PDF (365K) -
Fumiaki YOKOTA1992 Volume 41 Issue 5 Pages T59-T63
Published: May 05, 1992
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSIn order to determine silicon and other minor-trace elements in aluminium and aluminium alloy by ICP-AES, sample decomposition procedures were examined. A 0.2 g sample was taken in a 100 ml Teflon beaker and 10 ml of distilled water and 5 ml of sulfuric acid (1+1) were added and heated on a sand bath. Then 0.5 to 1 ml of 31 % hydrogen peroxide solution was added, and heated to dissolve the constituents except for silicon. The solution was evaporated to about 10 ml, and transferred to a Teflon pressure vessel to dissolve silicon. The vessel was kept at 230°C for 2 to 4 h in a drying oven. In some cases decomposition with 5 ml of sulfuric acid (1+1) and 0.5 to 1 ml of nitric acid was needed and the decomposition time was several hours longer. Using this procedure, aluminium and aluminium alloy samples containing up to about 0.5% of silicon could be completely dissolved. The proposed method was applied to aluminium and aluminium alloy samples. The analytical results were consistent with the certified values and the values obtained by JIS methods.View full abstractDownload PDF (723K) -
Susumu KAWAKUBO, Shuji YAMAMOTO, Masaaki IWATSUKI, Tsutomu FUKASAWA1992 Volume 41 Issue 5 Pages T65-T71
Published: May 05, 1992
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSAluminium down to 1 ppb was determined using less than 2 ml of acid or water sample. Reagent samples such as hydrogen peroxides, nitric, hydrochloric or hydrofluoric acid were evaporated to near dryness in a chamber under clean air flow. Aluminium-8-hydroxyquinoline-5-sulfonic acid complex was formed in 5 ml of 0.2 M acetate solution at pH 4.5, and was exited at 365 nm. The fluorescence was measured at 490 nm. Without any pretreatment, tap water, rain and snow were analyzed with chemical masking of copper, zinc etc. and with spectrophotometric correction for the effect of iron.View full abstractDownload PDF (756K) -
Yukio NAGAOSA, Kazuhisa ISHIDA1992 Volume 41 Issue 5 Pages T73-T76
Published: May 05, 1992
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThree different deproteinization methods for the liquid chromatographic determination of copper(II) and iron(III) in sera have been investigated for comparison. The analytical results obtained with both trichloroacetic acid-hydrochloric acid and methanol-hydrochloric acid are in good agreement with the recommended values. The method using perchloric acid gave negative errors for the determination of iron(III) in a serum (normal). For accurate determination, it was found that the two metal complexes with 8-hydroxyquinoline should be formed prior to injection onto an ODS column.View full abstractDownload PDF (540K) -
Yuzo TAMARI, Masako YOSHIDA, Shin TAKAGI, Kenji CHAYAMA, Haruo TSUJI, ...1992 Volume 41 Issue 5 Pages T77-T81
Published: May 05, 1992
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSSelenium content of biological samples was determined by AAS equipped with hydrogen selenide generation system. In this system, selenium(IV) was detected, whereas selenium(VI) was not detected. For the determination of total selenium in the samples, selenium(VI) should be reduced to selenium(IV) by boiling it with 6 M hydrochloric acid solution. When this reduction step was not applied to the samples wet-ashed with nitric acid or nitric acid-perchloric acid mixture, analytical values of selenium decreased because of the existence of the selenium(VI) formed at the wet-ashing procedure. NBS and NIES used Bovine Liver, Orchard Leaves, Rice and Tea Leaves, as standard reference material and the selenium content determined by this method agreed well with fluorometric and neutron activation analysis.View full abstractDownload PDF (639K) -
Yutaka KANAI1992 Volume 41 Issue 5 Pages T83-T86
Published: May 05, 1992
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSUranium contents and 234U/238U activity ratios in various aluminium reagents and bauxite samples were determined. The U content in Al(NO3)3·9 H2O reagent ranged from 0.9 to 12 ppb, and that in Al metal ranged from 40 to 680 ppb. The 234U/238U activity ratio varied sample by sample, and a large disequilibrium of 4.3 was observed in one reagent. Thus, it is important to consider contamination by U from Al reagents not only in U determinations but also activity measurements. Uranium contents and 234U/238U activity ratios in bauxite samples were also determined. The source of the contaminant U in Al reagents is considered to be bauxite.View full abstractDownload PDF (370K)
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