All issues
Volume 40, Issue 2
Displaying 1-14 of 14 articles from this issue
- |<
- <
- 1
- >
- >|
-
Yukihiro KONDOH, Akio YAMADA, Satoshi TAKANO1991 Volume 40 Issue 2 Pages 57-63
Published: February 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA HPLC method is described for the analysis of phospholipids. Twelve classes of diacyl glycerophospholipids and their lyso forms were separated by using aminopropyl silica column as a stationary phase and ethanol-acetonitrile-10 mM ammonium phosphate buffer (pH 5.80) as a mobile phase. Detection was accomplished using a postcolumn derivatization method. Phospholipids eluted from the column were hydrolyzed with potassium hydroxide. The glycerophosphoryl derivatives formed were oxidized to formaldehyde using periodic acid. The formaldehyde was then reacted with acetylacetone in the presence of ammonium acetate to form 3, 5-diacety1-1, 4-dihydrolutidine, which was detected at 410 nm. Each class of phospholipids was detected with an equal molar response regardless of their acyl moieties. The calibration curve was linear, for example, within a range from 1.1 to 111.0 nmol for phosphatidylethanolamine (PE). The relative standard deviation with six measurements was found to be 1.1 % for 33.3 nmol of PE. The acyl moieties of each phospholipids peak could be analyzed with reversed phase HPLC. A commercial soybean phospholipid was successfully separated and quantitatively analyzed with the proposed method.View full abstractDownload PDF (1364K) -
Tamio KAMIDATE, Masato OKUYAMA, Tadashi SEGAWA, Hiroto WATANABE1991 Volume 40 Issue 2 Pages 65-69
Published: February 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA chemiluminescence (CL) method was developed for the determination of pyruvic acid using enzymatic production of hydrogen peroxide from pyruvic acid. The oxidation of pyruvic acid was carried out with pyruvate oxidase at pH 6.8. Hydrogen peroxide formed was subsequently determined with a mixed solution of bis(2, 4, 6-trichlorophenyl)oxalate-perylene reagent containing a surfactant. The CL intensity depended upon the charge-type of surfactants. The best sensitivity was achieved using a cationic surfactant, hexadecyltrimethylammonium hydroxide. The calibration curve was linear in the range of 1 × 10-6 to 1 × 10-2 M and the detection limit was 3.5 × 10 -7 M for pyruvic acid. The relative standard deviation was 3.5% at 5.5 × 10-5 M of pyruvic acid. Determination of pyruvic acid in control serum was investigated. Proteins such as albumin caused a reduction of the CL intensity. The interference by proteins can be avoided by employing 5% metaphosphoric acid as the protein-precipitating reagent. The present method may be applicable for the determination of pyruvic acid in serum.View full abstractDownload PDF (937K) -
Mikio ISHIKURO, Minoru HOSOYA, Kunio TAKADA1991 Volume 40 Issue 2 Pages 71-76
Published: February 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSTrace amounts of phosphorus in high purity iron were determined by using molybdate-Malachite Green (MoP-MG) and molybdate-Brilliant Green (MoP-BG) spectrophotometric methods, following separation by beryllium hydroxide coprecipitation. The recovery of trace amounts of phosphorus by beryllium hydroxide coprecipitation was 98.7%. The spectra were measured using hydrochloric acid solution. These ion-association complexes were insoluble in water, however, they could be dispersed by addition of polyvinyl alcohol. Arsenic was removed from the sample solution as arsenic(III) bromide. The following procedure was used : The sample (1.0 g) was dissolved in nitric acid. Perchloric acid was added and the solution was heated until fumes formed. One hundred milliliters of 7% EDTA solution and 5 ml of beryllium solution (1 mgBe/ml) were added. The sample solution was converted to alkaline by addition of ammonia solution. After cooling, the precipitate formed was filtered off. The precipitate and filter paper were dissolved in mixture of nitric and perchloric acids. One milliliter of hydrobromic acid was added and the solution was then evaporated to dryness in order to remove arsenic and perchloric aicd. Two milliliters of molybdate solution (1 % ammonium molybdate in 6 M hydrochloric acid) were added. The solution was transferred to a test tube. One milliliter of 1% polyvinyl alcohol solution and 2.0 ml of 0.05% MG or BG solution were added. The solution was then diluted to 20.0 ml with water and mixed. The solution was heated in a boiling water bath for 7 min. Then it was cooled for 30 min. The absorbance at 605 nm (MoP-MG) and 635 nm (MoP-BG) were measured. The molar absorptivities of MoP-MG and MoP-BG were 1.2 × 105 and 8.2 × 104l mol-1 cm -1 respectively. The relative standard deviation for the determination of phosphorus (0.32 μg/g) in high purity iron was 6.5% with 6 replicates.View full abstractDownload PDF (968K) -
Yoshifumi HARADA, Natsuko KURATA, Giichi FURUNO1991 Volume 40 Issue 2 Pages 77-82
Published: February 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSImpurities (16 elements) in high-purity mullite powder and alumina powder were determined by the following procedure : A 0.5 g sample of mullite or alumina was placed in a platinum crucible. It was heated with hydrofluoric acid and sulfuric acid on a hot plate, and evaporated to dryness. The residue was heated with hydrofluoric acid and phosphoric acid. Heating was continued until the opaque appearance of the mixture changed to a clear-syrupy fluid. The fluid in the crucible was dissolved in water and then diluted to 100 ml. ICP-AES determination and AAS for K were made. The phosphoric acid matrix reduced the emission intensities of the elements except for Cu and increased appreciably the background levels of Cu, Fe, Ni and Zn. The aluminium matrix enhanced the emission intensities of Cu, Li and Na because of interference of aluminum in plasma. But it reduced the emission intensities of the other elements. Therefore, the matrix concentrations of the standard solutions were closely matched with those of mullite or alumina sample solutions. The analytical results show that the proposed method is useful for the rapid determination of impurities in mullite and alumina with average diameter of sub-micron.View full abstractDownload PDF (931K) -
Michiko KAKEMOTO, Kazuo MURAKAMI, Yosefu YAMADA1991 Volume 40 Issue 2 Pages 83-87
Published: February 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA specific and sensitive high performance liquid chromatographic method using a electrochemical detector and pretreatment method is described for the determination of p- hydroxybenzoic acid esters that are used as preservatives in cosmetics. Seven p- hydroxybenzoic acid esters were separated using Chemcosorb 5-ODS-H (4.6 × 100 mm) as the stationary phase and 0.2 mmol/dm3 perchloric acid methanol solution-0.05 mol/dm3 acetic acid solution (pH 3)-pyridine (75 : 25 : 0.5 vol % ) as the mobile phase. The order of elution was as follows : methyl, ethyl, isopropyl, n-propyl, s-butyl, isobutyl and n-butyl. The potential of electrochemical detector was set at +1.2 V vs. Ag/AgCl. The linear dynamic range was approximately 1× 103 (1× 10-101 × 10-7). The minimum detectable amount for the metyl ester was found to be 50 pg and 50150 pg for other esters. The electrochemical detection method was more sensitive than UV detection at 254 nm. This method was applied to determination of p-hydroxybenzoic acid esters in cosmetics.View full abstractDownload PDF (891K) -
Yukihiro KOSHINO, Akira NARUKAWA1991 Volume 40 Issue 2 Pages 89-92
Published: February 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA simple method without matrix interference for the direct determination of Al, Fe, Ni, Cr, Mn and Cu in sulfur by graphite furnace AAS has been developed. Effect of sulfur matrix could be removed easily by preheating furnace at 120500°C, and integrated absorbance-time profile with small background absorption was obtained. Furthermore, metal standard solutions could be used as calibration standards by using pyro-coated L'vov platform graphite tube. This proposed method was applied to the rapid determination of the trace metal elements in sulfur samples, using 15 mg sample weight. The relative standard deviations of analytical values were within 10%. Accuracy of this method was checked by the HNO3-Br2 decomposition/ICP-AES method.View full abstractDownload PDF (804K) -
Hiroki OHURA, Toshihiko IMATO, Sumio YAMASAKI, Nobuhiko ISHIBASHI1991 Volume 40 Issue 2 Pages 93-96
Published: February 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA simple and rapid FIA of phenol is described, using bromination reaction and a potentiometric detection. The detector is a combined electrode which consists of a bromide-selective electrode and a platinum electrode arrayed in series. The method is based on the measurement of potential changes in an initial stage of the bromination of phenol in a flow system. The sample is injected into a stream of carrier water and merged with a stream of acidic bromine solution which brominates phenol in the reaction tube. The amount of reduced bromine is determined by measuring the potential change with a potentiometric detector, giving the concentration of phenol in samples. A linear relationship between peak heights and phenol concentrations is observed in the range of 5×10-6 M to 2.5×10-5 M phenol. The relative standard deviation was 0.9% for analysis of 5×10-6 M phenol at sampling rates of 80 h-1.View full abstractDownload PDF (648K) -
Kousei MIZUSHIMA, Keisuke UMAKOSHI, Yasuhiro IMAKURA, Kensuke CHIKAMOR ...1991 Volume 40 Issue 2 Pages 97-99
Published: February 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSFor the determination of trace matals in a sample, such as rain water, contamination from the supporting electrolyte solution and the standard solution are not negligible. In this study, the relationship between the composition of the solution in the statndard addition method and the response signal was analyzed. It was concluded that two correction terms for eliminating contamination were added to the usual formula used to determine. The trace metals, such as Cu(II), Pb(II), Cd(II) and Zn(II) in rain water were determined by anodic stripping voltammetry with the supporting eletrolyte solution containing 7.68×10-2 M tartaric acid and 3.84×10-2 M ammonium acetate. The proposed method can be used to determine ppb level of trace metals with good precision.View full abstractDownload PDF (360K) -
Haruki SEGAWA, Tohru SAITOH, Tamio KAMIDATE, Hiroto WATANABE, Kensaku ...1991 Volume 40 Issue 2 Pages 101-104
Published: February 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSAcid dissociation constants of 2-(2-pyridylazo)phenol (PAP) and 2-(2-pyridylazo)-5-methylphenol (PAP-5Me) and the stability constants of their chelates with vanadium(V), nickel(II), and iron(II) were determined by spectrophotometry at 293 K and μ=0.1. The acid dissociation constants were; pKa1(PAP)=2.53, pKa2=8.76, pKa1(PAP-5Me)=2.67 and pKa2(PAP-5Me)=8.95.Since iron(II)-PAP chelate was insoluble in water, its stability constant in water was determined by an extrapolation of stability constants in aqueous dioxane. Other stability constants were determined directly in water. They were;logβ1{V(V)-PAP}=12.43, logβ1{Ni(II)-PAP}=9.79, logβ2{Ni(II)-PAP} =21.78, logβ1{Fe(II)-PAP}=11.95, logβ2{Fe(II)-PAP}=24.45, logβ1{V(V)-PAP-5Me}=12.87, logβ1{Ni(II)-PAP-5Me}=10.67, logβ2{Ni(II)-PAP-5Me}=22.17, logβ2{Fe(II)-PAP-5Me} =25.51.View full abstractDownload PDF (480K) -
Yoshio MUKAI, Hisako HARA, Hirokazu TANIGUCHI1991 Volume 40 Issue 2 Pages 105-107
Published: February 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSFluorometric determination of nitrite with 2, 3-diaminonaphthalene (DAN) has been investigated. By removing some of the impurity contained in DAN, the sensitivity of the analytical conditions (concentration of reagent, reaction time and temperature) were extended over that of the conventional methods. Nitrite was determined in the range of 22000 ng. The relative standard deviation (R.S.D.) was 0.7% (n= 5) at 100 ng of nitrite. The presence of thiosulfate and ascorbic acid interfered. This method was also applied to the determination of amyl nitrite. Amyl nitrite was first dissolved in glacial acetic acid and was then diluted with water. The solution was analyzed in a similar manner as nitrite. Amyl nitrite was determined in the range of 0.0220μg. The R.S.D. was 1.1 % (n=10) at 2μg of amyl nitrite.View full abstractDownload PDF (476K) -
Isami WATANABE1991 Volume 40 Issue 2 Pages T25-T29
Published: February 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA method to determine trace levels of chromium(VI) in aqueous solution was investigated. The sample was concentrated by precipitation using sodium dibenzyldithiocarbamate(DBDTC), collected by filtrattion on a membrane filter, dried and then analyzed quantitatively using XRF. The best conditions to form complexes of 0100μg of Cr(VI) in 100 ml of aqueous solution with DBDTC were as follows : pH value approximately 4, aging time of approximately 15 min and an addition of approximately 3 ml of DBDTC (as a 1% solution in methanol). Under these conditions, a linear calibration curve was obtained in a range of 0100μg of Cr(VI)/100 ml. The lower detection limit was 0.07μg/100 ml. The effect of coexisting ions on the precipitation efficiency of 20μg of Cr(VI)/100 ml was examined. The addition of Ca(II), Mg(II), Fe(III), Cu(II), Si(IV), Na(I) and Cl-, up to 1000 μg of each, did not show any effect. The addition of 1000 μg of Cr(III) gave a slightly positive interference. The existence of more than 500 μg of Ni(II) or Zn(II) and more than 100 μg of Mn(II) gave negative deviation for the determination values. Groundwater from two different locations in the East Kanto district was measured. The Cr(VI) values obtained by the present and by JIS methods were in agreement with each other.View full abstractDownload PDF (702K) -
Yusuke KUNO, Tetsuro HINA, Souichi SATO, Takao AKIYAMA1991 Volume 40 Issue 2 Pages T31-T35
Published: February 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSApplicability of differential pulse voltammetry to in-line uranium and plutonium analysis in nuclear fuel preprocessing plant was investigated. The electrode probe was composed of only noble metals. It was designed so that disturbance from solution flow was minimized. It became obvious that the voltammetry can be applied to the direct measurements of uranium (1200gl-1) and plutonium (0.520 gl-1) in the highly radioactive process streams with precision of approximately 5%. The presence of small amount of hydrazine interfered with plutonium measurement.View full abstractDownload PDF (816K) -
Mikio ARAMATA, Yasutoshi KAWATE, Naoya NOGUCHI1991 Volume 40 Issue 2 Pages T37-T40
Published: February 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSSilicone vapor or aerosols in the environment in which the electrical contacts operate might cause failure of electrical contacts. Development of both sampling and detection methods of silicones in the air are very important in analyzing the failure of electrical contacts. In this study, silicone vapor is collected using an activated charcoal adsorption column. The extract from activated charcoal with tetrachloromethane is analyzed by pyrolysis GC. The pyrolysis fragments are low molecular cyclic dimethyl siloxanes such as hexamethylcyclotrisiloxane. As little as 1ng/ml of a given viscosity dimethyl silicone may be detected using this analytical method. This was applied to the determination of silicone vapor in the air with satisfactory results.View full abstractDownload PDF (615K) -
Akio SAKURAGAWA, Yasuhiro KINOSHITA, Tadao OKUTANI1991 Volume 40 Issue 2 Pages T41-T46
Published: February 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSFlow-injection spectrophotometric determination of trace amounts of cyanide ion on the basis of catalytic effect was investigated. p-Nitrobenzaldehyde reacts with cyanide ion to yield intermediate cyanohydrin. The cyanohydrin causes the reduction of ο-dinitrobenzene, characteristic blue color of the ο-nitrophenylhydroxylamine dianion(λmax: 555 nm). The sample (100 μl) injected into a 0.10 M sodium hydroxide stream was mixed with a stream of ethylene glycol monomethyl ether (EGME). This mixture was merged with the stream of a pre-mixed reagent solution, which was prepared by mixing 0.20 M p-nitrobenzaldehyde EGME solution with an equal volume of 0.15 M ο-dinitrobenzene EGME solution. The absorbance change of the spectrophotometric detector was observed as a peak-shaped signal. Cyanide ion in a sample was determined by a relationship between the peak height and the concentration of standard cyanide ion solution. By this method, ppb levels of the cyanide ion can be determined. The relative standard deviation for 50 ppb cyanide ion (n=10) was 1.2%. The proposed method was used to determine the presence of the cyanide ion in waste water samples. The samples were prepared by a microdiffusion method using EDTA and succinic acid.View full abstractDownload PDF (905K)
- |<
- <
- 1
- >
- >|