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Volume 36, Issue 6
Displaying 1-14 of 14 articles from this issue
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Koichi YAMAMOTO, Shoji MOTOMIZU1987 Volume 36 Issue 6 Pages 343-347
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSTrace amounts of Cu in steel, stainless steel and aluminium alloys were spectrophotometrically determined after solvent extraction of an ion associate formed between dichlorocopper(I) ion (CuCl2-) and Ethyl Violet. The procedure is as follows. Dissolve the sample by heating with dilute sulfuric acid or aqua regia. Then, evaporate the resulting solution nearly to dryness. If aqua regia is used for dissolution of the sample, add dilute sulfuric acid to the resulting solution and evaporate nearly to dryness. Dilute the residue to a fixed volume with water. Pipette an adequate volume of the sample solution into a stoppered test tube. Add ascorbic acid and potassium chloride solutions, and adjust the pH of the solution to about 4.1 with acetate buffer. Add Ethyl Violet solution and extract the ion associate formed between dichlorocopper (I) ion and Ethyl Violet to 5 ml of toluene. Measure the absorbance of the organic phase at 612nm. The proposed method is very sensitive (molar absorptivity: 105 1 mol-1 cm-1) and the interference of coexisting ions is negligible. Copper above 0.011% in the sample can be determined by this method.View full abstractDownload PDF (727K) -
Shigeo AOYAGI, Miyoko KUSUMI, Akira MATSUYUKI, Masako MAEDA, Akio TSUJ ...1987 Volume 36 Issue 6 Pages 348-351
Published: June 05, 1987
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSThe determination of hydrogen peroxide was performed by chemiluminescent and colorimetric methods.The light emitted from chemiluminescent reaction was measured with a Luminometer UPD-8000 (Meidensha Electric Mfg., Co., Ltd.). The detection limit was 1 pmol/tube in chemiluminescent method and 1 nmol/tube in colorimetric method. The calibration curves were obtained in the range from 1×10-8 to 1×10-3 M by chemiluminescent method and from 1×10-5 to 1×10-3 M by colorimetric method. In order to reduce nonspecific binding which reduces the sensitivity of sandwich enzyme immunoassay (EIA), the effect of addition of various proteins was studied. Guinea pig serum was found to be the most effective one. Basedon these experimental results, chemiluminescent EIA for insulin using β-D-glucose oxidase (GOD) as label enzyme was established. The anti insulin IgG-GOD was prepared by Ishikawa's method. The detection limit of this chemiluminescent EIA for insulin was 0.5 μU/tube and the regression line was Y (EIA)=1.21X(RIA) -3.60 (the correlation coefficient r=0.95).View full abstractDownload PDF (656K) -
Hiroomi NAKAMURA, Koji YONEDA, Yoshiaki KATAYAMA, Yoshinori KIDANI1987 Volume 36 Issue 6 Pages 352-355
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA simple and rapid method for fractionating serum bilirubin by means of HPLC has been established by modifying the method of Lauff et al. In our procedure, the cumbersome and time-consuming pretreatment of serum in the previous method is replaced by the use of the guard column (Hiber Lichro CART 4-4, Merck). This guard column retains high-molecular weight serum proteins to protect the analytical column from the irreversible adsorption, and it is changed every 20 samples or whenever the tailing is observed in the chromatogram. The present method requires only the dilution of 50μl of serum with 500μl of sodium chlorate solution (0.2w/v% sodium chlorate and 0.05v/v% Triton X-100 in 0.5M phosphate buffer, pH 6.8), and subsequent filtration of the mixture through a 0.45μm Millipore filter. Ten microliters of the filtrate is injected into the column; the HPLC conditions are the same as described by Lauff. The four fractions of serum bilirubin are obtained. The relative standard deviations for each bilirubin concentration in the fractions are 5.4 to 16.7% (n=5). The correlation coefficients with other methods including the Lauff's method are 0.863 to 0.974.View full abstractDownload PDF (619K) -
Yoshinaga KOUJI, Toshio MATSUDA, Toyoshi NAGAI1987 Volume 36 Issue 6 Pages 356-361
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe adsorption behavior of Cr(VI) and Cr(III) on hydrous lead dioxide (HLD), freshly prepared by hydrolysis of lead tetra-acetate, was examined using spectrophotometry with diphenylcarbazide. Also, the effect of the presence of Pb(II) on the adsorption behavior of those ions was investigated. HLD(5×10-4mol, about 0.14g of PbO2·2H2O)was used for each adsorption test at a solution volume of 100ml.After shaking, Cr(VI) was readily adsorbed on the HLD below pH 7, and maximal adsorption was observed at about pH 2. The species of Cr(VI) adsorbed was considered to be HCrO4-, and the adsorption equilibrium was reached within 1h. Almost 100% adsorption was observed for the solution at about pH 3 when the concentration of Cr(VI) was less than about 2×10-5M. Cr(III) was adsorbed as aquachromium(III) on HLD below pH 2, while above pH 3 Cr(III) was easily oxidized to Cr(VI) with HLD so that Cr(III) was adsorbed in a similar manner as Cr(VI). The addition of Pb(II) increased the adsorption of both Cr(VI) and Cr(III) over the pH range from 3 to 10. As the value of the concentration products of Pb(II) and Cr(VI)for the supernatant solution at pH 6 after shaking with HLD agreed very closely with the calculated conditional solubility products of Pb(II) chromate at pH 6.0, the decrease in Cr(VI) concentration was attributed to the coprecipitation of lead(II) chromate with the HLD. HLD can be used for the collection or the removal of Cr(VI) and Cr(III) in environmental samples or in waste water.View full abstractDownload PDF (1039K) -
Masayuki KUNUGI, Tsuguo MIZOGUCHI, Chiaki NAKATOMI, Norio YAMAGUCHI1987 Volume 36 Issue 6 Pages 362-366
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe fluorescence method is one of the excellent analytical methods for monitoring sulfur dioxide in the atmosphere. However, it has several instrumental problems such as zero drift, span drift and stability. The reasons for these problems are the decrease in the incident light intensity of xenon lamp with time and the fluctuation of its pulse-to-pulse intensity. In the present study, we have developed a compensation system consisted of following three components: 1) a monitor by silicon photodiode for incident light intensity, 2) an analog memory for monitoring intensity, and 3) a divider unit. The system has reduced zero and span drifts by about five times compared with those without it. The results have been theoretically discussed.View full abstractDownload PDF (828K) -
Wataru YOSHIMURA, Atsushi UZAWA1987 Volume 36 Issue 6 Pages 367-370
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe square-wave polarographic determination of Cd in seawater by coprecipitation with zirconium hydoxide was carried out. A square-wave polarograph system consisting of Shimadzu type PR-50 and Shimadzu type SWP-50 was used and the anode was a mercury pool in electrolytic cell. Zirconium oxychloride containing 30 mg of Zr is added to 2000 ml of seawater and pH is adjusted to 8.2 with aqueous ammonia (1:2). The precititate is separated by filtration and then dissolved in 25 ml of 4 M hydrochoric acid. The solution is diluted to 50 ml with distilled water. A portion of this solution is submitted to the polarographic determination. The polarogram is recorded over the range from -0.40 V to -0.80 V vs. Hg-pool. The results are as follows: (1) Cd in seawater can be coprecipitated quantitatively when the pH is adjusted to 8.2. (2) Cd concentration determined by this method is 1.38 ppb. (3) Effect of various kinds of foreign ions is examined. As(III) Fe(III) and Bi(III) ions interfer with the polarographic determination of Cd remarkably.View full abstractDownload PDF (509K) -
Shin'ichi HASEGAWA, Takeshi KOBAYASHI, Fumio HIROSE, Haruno OKOCHI1987 Volume 36 Issue 6 Pages 371-375
Published: June 05, 1987
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSTrace quantities of Ga in ores were determined by graphite furnace AAS after solvent extraction. The analytical procedure is as follows; 0.5 g are is fused with 2 g sodium dioxide. After aqueous leaching, hydrochloric acid is added to make the solution acidic. Twenty mililiters of perchloric acid is added and the solution is heated until the appearance of fumes. Twenty mililiters of 10% ascorbic acid is added in order to reduce Fe (III) and Ti(IV) {in the case of a Ti(IV) oxide content higher than 5%, 25 ml of 20% ascorbic acid is used}. The pH of the solution is adjusted to 2.5±0.1 with 20% ammonium acetate. Gallium is extracted with 40 ml of 0.01 M 8-quinolinol in chloroform and re-extracted from the organic phase with 30 ml of 1.5 M nitric acid. The water phase is gently heated in order to expel the chloroform dissolved. Five mililiters of nickel nitrate solution (50 mgNi/ml) is added for matrix modification. The solution is transferred to a 50 ml volumetric flask. An aliquot of 20μl is injected on a graphite furnace equipped with a platform and the absorbance of Ga is measured at 417.2 nm. The analytical precision was obtained by repetitive determination of Ga in JSS 800-2 (Rompin Hematite). The averaged analytical value was 0.0012o% and the relative standard deviation was 1.62%. The limit of detection(3σ) is 0.13 ppm for 0.5 g sample taken. The pyrolytically coated graphite furnace equipped with a platform made it possible to determine the analyte more precisely and ca.300 repetitive firing with one graphite furnace became also possible.View full abstractDownload PDF (924K) -
Haruo HONMA, Hisako YANASHIMA, Mutsuko YOSHIDA, Keiko SUZUKI1987 Volume 36 Issue 6 Pages 376-380
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSSeveral analytical conditions were studied to determine Si in organic compounds with satisfactory precision. Octaphenyl cyclotetrasiloxane was selected as a sample because its carbon and hydrogen contents were in good agreement with the theoretical values. A mixture of 50% nitric acid and 50% sulfuric acid was the most suitable as a digestion medium. The sample sublimed without decomposition when digestion was carried out in 50% nitric acid, and the resulting value was extremely low. Using 50% sulfuric acid, the formed silicon dioxide had hygroscopic character. When the flow rate of air was too fast, silicon carbide was produced partly due to the evaporation of the digestion medium. Thus 0.2 ml/min was the recommended flow rate for the complete formation of silicon dioxide. The proposed heating program was as follows:dissolution, 200°C; wet ashing, 300330°C;dry ashing, 600°C; calcination, 950°C. The total analytical time was 40 min. The relative standard deviation was 0.0025 for this method.View full abstractDownload PDF (767K) -
Harumitsu NISHIKAWA, Tomokuni HAYAKAWA, Tadao SAKAI1987 Volume 36 Issue 6 Pages 381-385
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA method for the determination of low-molecular weight aliphatic aldehydes in exhaust gas and thermal degradation emission was investigated. Aldehydes in sample gas (230 l) were collected by passing the gas at a flow rate of 0.5 l/min through two impingers connected in series. Each impinger contained 10 ml of ethanolic solution of O-pentafluorobenzylhydroxylamine at a concentration of 0.3 mg ml-1. After sampling, the absorption solution was diluted with ethanol to 20 ml and allowed to stand for 80 min at room temperature. A 10 ml portion of this solution and 20 ml of distilled water were mixed together. The mixture was passed through a Sep-Pak C18 cartridge. The derivatives in the cartridge were eluted with 1.5 ml of hexane and the eluate was analysed by capillary GC with a flame thermionic detector. Formaldehyde, acetaldehyde, propionaldehyde and butyraldehyde were determined easily and selectively without interference of ketones. The collection efficiencies for these compounds from the standard gas were more than about 90%. The determination limits were 14 ppb for formaldehyde, 10 ppb for acetaldehyde, 67 ppb for propionaldehyde and 38 ppb for butyraldehyde when 30 l sample gas was used.View full abstractDownload PDF (650K) -
Toru NOZAKI, Yukihiro YAMAMOTO, Masako MISE, Shigehisa KOBAYASHI, Kuni ...1987 Volume 36 Issue 6 Pages 386-389
Published: June 05, 1987
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSIon flotation of Co(II), Ni(II), Cu(II), Zn(II), Cd (II) and Pb(II) in ammonium pyrophosphate solutions with cationic surfactant, cetylpyridinium chloride (CPC), was investigated. A 20 ml of (1.010.5)×10-4M ammonium pyrophosphate solution (pH 6.510.5) containing (7.89.4)×10-5M of a divalent metal ion and(1.014)×1.0-3M of CPC was subjected to flotation in a 2.7 cm i.d.×20 cm cell for about 10 min with nitrogen bubbles. The metals were floated from the respective metal solutions in 92100% yield. Separation of Cu(II) from Ni(II) and Co(II), and Zn(II) from Ni(II) were achieved fairly well in 4.19×10-4M pyrophosphate solutions with 1.40×10-3 M CPC. The analysis of the relations between the mean number of the ligand P2O74- per each metal and the concentration of pyrophosphate by means of the molar ratio method, suggested the existence of the species such as [MP2O7]2-, [M(P2O7)2]6- and [M(P2O7)]10- in (0.11.15)×10-3M pyrophosphate solutions (pH 6.58.5).View full abstractDownload PDF (628K) -
Application to coprecipitation solid samples with chelating reagents for the determination of sub-ppb level of copper in water samplesKoji ITOH, Ikuo ATSUYA1987 Volume 36 Issue 6 Pages 390-395
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA highly sensitive, accurate, precise and simple method for the determination of ultra-trace amounts of Cu (II) in natural water was established by the direct determination of solid samples obtained by a coprecipitation with chelating reagents by polarized Zeeman AAS with miniature cup solid sampling technique. Nickel and dimethylglyoxime(DG) were used as a carrier metal ion and complexing agent respectively. Conditions for coprecipitating Cu with bis (dimethylglyoximato) Ni (II) were examined, and 1- (2-pyridylazo)-2-naphthol (PAN) was added for facilitating the coprecipitation of Cu. In the presence of 2 mg of PAN per 4 mg of Ni, the recovery of Cu increased from 50 to 95%. Based on these examinations, a recommendable analytical procedure has been established. A sample solution (100500 ml) was taken in a borosillicate glass beaker and then 4 mg of Ni (II) was added as carrier ion. After addition of 1 ml of 1.75% DG and 0.2% PAN ethanol solution, pH was ajusted with conc. ammonium hydroxide to 810. After standing for 1 h at 60 °C, the precipitate was collected by a fine glass frit (pore size 510 μm) and dried in an oven for 1 h at 110°C. Enrichment factor of this method reached to 15000, when 300 ml of sample solution was used and the weight of coprecipitation obtained was 20 mg. In this case, detection limit was 0.01 ppb. Relative standard deviations (ca. 210%) was shown for each measurement.View full abstractDownload PDF (1092K) -
Hiroshi NAKAZAWA, Masayuki NAGASE, Toshio ONUMA1987 Volume 36 Issue 6 Pages 396-398
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSIn many cases, synthetic peptides are formed as their acetates. However, contamination with other anions such as trifluoroacetate and fluoride ion might be caused by synthesis and/or purification processes. Therefore, the analytical method for anions in peptide preparations is required; no study has been reported except for the analysis of acetate by GC. This paper presents a sensitive and reproducible method for determination of anions in the peptide samples by ion chromatography, using an anion exchange column and 0.5 mM sodium bicarbonate (for fluoride ion and acetate) or 4 mM sodium bicarbonate (for trifluoroacetate) as a mobile phase. The calibration curves were linear in the range of 125 μg/ml of fluoride ion, acetic acid or trifluoroacetic acid. The detection limit (S/N=3) was 0.01 μg/ml for fluoride ion, and 0.1 μg/ml for acetic acid and trifluoroacetic acid, respectively. The reletive standard deviation of 5 repeated analyses was 1.3% for 1 μg fluoride ion/ml, 1.2% for 4 μg acetic acid/ml and 1.1 % for 4 μg trifluoroacetic acid/ml, respectively. Several synthetic peptides (growth hormone-releasing factor and its fragment) were analyzed by the present method.View full abstractDownload PDF (383K) -
Masaru KUNIMURA, Toshio OGAWA1987 Volume 36 Issue 6 Pages 398-402
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSVarious kinds of elements are generally contained more or less in plastics as catalysts, additives or fillers. We tried to determine several elements in polyethylene sheets using an electron probe microanalyzer (EPMA). Polyethylene sheets containing given amounts of fine powder of inorganic compounds were prepared by hot press at 180 °C. Sheet surface was coated with gold in order to make it electro-conductive. It was confirmed that iron and calcium could be determined in the range from 0.1 to 30 wt% with a fairly good accuracy by the use of calibration curves of relative intensity vs. content. Possibility of quantitative determination was examined for 26 elements by classifying into four groups according to the type of analyzing crystals. All the elements studied gave linear calibration curves. Especially the elements measured with LiF as the analyzing crystal had large possibility for determination, because the calibration curves could be actually expressed by a line for all the elements examined here.View full abstractDownload PDF (521K) -
Setsuko KUDO, Choetsu HOSONO, Shokou TERASAWA, Ikuyo SAITO, Nobuo SUZU ...1987 Volume 36 Issue 6 Pages T61-T65
Published: June 05, 1987
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe potentiometric titration method was applied to the determination of chloride ion of 10 mg/l or above in boiler water from low-pressure boilers. A silver electrode was used as the indicator electrode. Procedure: To a sample containing 0.55mg of chloride ion, add water up to ca. 50 ml in total volume and 2 ml of HNO3 (1 mol/l), titrate with 0.01 mol/l AgNO3. A satisfactory linear relationship was obtained between the analytical value by the present method and that by the spectrophotometric method with Hg(SCN)2.View full abstractDownload PDF (740K)
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