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Volume 43, Issue 9
Displaying 1-11 of 11 articles from this issue
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Ikuo ATSUYA1994 Volume 43 Issue 9 Pages 661-678
Published: September 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe direct analysis of soild samples by graphite furnace AAS consists of direct solid sampling and slurry sample introduction. The advantages of using solid sampling and the different kinds of problems associated with it discussed. In the case of using direct solid sampling, the sample introduction systems of various kinds of atomizers, the preparation methods of calibration graphs, concentration techniques for powdered biological samples and applications of direct solid sampling are described in detail. Distinguishing features and basic problems for slurry sample introduction are discussed and application examples of the slurry sampling technique are described.View full abstractDownload PDF (3487K) -
Koichi YAMAMOTO, Keiko HIRAIWA1994 Volume 43 Issue 9 Pages 679-683
Published: September 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA colloidal titration method for ionic surfactants with bromochlorophenol blue(BCPB) as an indicator was examined. A monovalent dye anion HBCPB- reacts with cations (C+) such as polydiallyldimethylammonium chloride (Cat-Floc) and quaternary ammonium salt containing a long-chain alkyl group, to form an ion associate (C+)2·BCPB2-, causing a color change from yellow to blue. An anionic surfactant (AS) solution at pH 3.3 is titrated with a polycationic titrant, Cat-Floc, until an ion association of AS with Cat-Floc, followed by the formation of a 2 : 1 ion associate (Cat-Floc+)2· BCPB2- causes a color change from yellow to blue. A cationic surfactant (CS) solution at pH 3.3 is titrated with a polyanionic titrant, polyvinylsulfate (PVSK), until CS forms a 1: 1 ion associate CS+·PVSK- rather than a 2:1 ion associate (CS+)2·BCPB2-to cause a color change from blue to yellow. AS at concentrations from 10-5 to 10-4 mol dm-3 and CS at concentrations from 10-5 to 4×10-4 mol dm -3 could be determined by the proposed method. The proposed method was applied to the determination of anionic surfactants in commercial detergents, and the results were in good agreement with those of the JIS titration method (Epton method).View full abstractDownload PDF (816K) -
Akitoshi OKINO, Hiroaki ISHIZUKA, Issei HIRAYAMA, Yuji NOMURA, Ryuichi ...1994 Volume 43 Issue 9 Pages 685-689
Published: September 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSHelium inductively coupled plasma using an enhanced vortex flow torch for the analysis of aqueous samples was developed. The present study reports the spectroscopic measurements of electron number densities, helium excitation temperatures and OH rotational temperatures in the helium ICP. Significant increases in electron number densities but decreases in rotational temperatures were observed, upon increased introduction of carrier gas. The experimental results suggest that the local thermodynamic equilibrium (LTE) is not consistent, and the effects of aqueous sample introduction on the plasma parameters are greater than in the case of conventional argon ICP. Moreover, the doughnut like profile of electron number densities and plasma temperatures reported for argon ICP were not observed in the helium ICP. The helium excitation temperature, OH rotational temperature and electron number density are 4100 K, 2200 K and 0.75 × 1014 cm-3, respectively at 900 W of RF input power.View full abstractDownload PDF (882K) -
Keiji GAMOH, Maki SAKAMOTO1994 Volume 43 Issue 9 Pages 691-696
Published: September 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSAn indirect liquid chromatographic determination method for the hydroxyl radical in an aqueous system was described. The method is based on the production of methanesulfinic acid as the primary product by the reaction of hydroxyl radical with dimethyl sulfoxide. The methanesulfinic acid formed was coupled with diazonium salt to afford the diazosulfone derivative, which was detected and equantified by reversed-phase liquid chromatography at 420 nm. The practical conditions for the methanesulfinic acid detection were optimized. Linearity of the methanesulfinic acid formation was observed in the range from 0.5×10-3mM to 10×10-3 mM. To evaluate this method for estimating hydroxyl radical production, two model systems, including the Fenton reaction and ultraviolet photolysis of hydrogen peroxide were studied. The theoretical maximum yield of hydroxyl radical in the systems could be calculated and compared to the measured dimethyl sulfoxide oxidation. The estimated concentration of hydroxyl radical from 80×10-3mM of hydrogen peroxide in the Fention reaction was 7.4×10-3mM. The present method may prove useful for detecting hydroxyl radical involvement in biological samples.View full abstractDownload PDF (865K) -
Takeshi OBATA, Shigenori MAEDA, Ryuichi GOTO, Mayuko MASUDA1994 Volume 43 Issue 9 Pages 697-702
Published: September 05, 1994
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSThe determination of trace impurities in high purity cobalt is increasingly required because it is a raw material in the production of cobalt di-siliside, a useful material for very large scale integrated circuits owing to its very low electrical resistivity and high melting point. Therefore a highly precise, sensitive and rapid method for the determination of impurities in high purity cobalt by glow discharge MS (GDMS) is presented. For determination of the elements of interest, the optimum discharge voltage, current, electrode distance, and sample area were found to be 1 kV, 2.5 mA, 0.6 mm, and 12 mmφ, respectively. The mass spectrum of GDMS showed that the ion peaks of some impurities overlapped with, or were close to complexed molecular ion peaks. Such mass interference of the complexed molecular ion was reduced by cooling the sample with liquid nitrogen. In order to obtain precise quantitative values, the relative sensitivity factors for impurities in cobalt were determined by using laboratory reference samples, where the amounts of trace elements were determined by chemical analysis. For 8 elements examined here, the analytical results obtained by GDMS were in good agreement with those obtained by chemical analysis. Determination limits were 5 ppb for Li, Na, Cr and Fe, 50 ppb for K and Ni, and 0.1 ppb for Th and U, respectively.View full abstractDownload PDF (873K) -
Katsumi UCHIYAMA, Minoru FUJITA, Junichi MINOWA, Yoshihiro YOSHIMURA, ...1994 Volume 43 Issue 9 Pages 703-708
Published: September 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSPhotoacoustic determination of protein by use of a solid-phase concentration method on a nitrocellulose membrane filter by the avidin-biotin complex method is detailed. The membrane was cut into a 15 mm circle and set on the self-made suction filtering apparatus. After protein was adsorbed on the membrane filter, the adsorbed protein was biotinylated by incubation with N-hydroxysuccinimide biotin. The biotinylated protein was incubated with avidin-horseradish peroxidase and was then colored by 4-chloro-1-naphthol in the presence of hydrogen peroxide and the photoacoustic signal was measured. The photoacoustic intensity shows a maximum in the presence of 100 mM MgCl2 in the sample solution. The photoacoustic intensity was decreased by the presence of sodium, dodecyl sulfate and urea. A linear relationship was obtained between the amount of ovalbumin (OVA) and the photoacoustic intensity in the range of 1300 ng. The detection limit of OVA was approximately 0.8 ng (S/N=2). The coloration of avidin-biotin complex was decreased by irradiation with a He-Ne laser. Using 1 ml of five different water samples: ice, tap water and three natural water samples (from Japan, Canada and Switzerland), protein in the form of OVA was found at concentrations of 150, 58, 26, 14 ng and N.D. respectively. The recovery of OVA (200 ng) added to the tap water was determined to be 104.3%.View full abstractDownload PDF (877K) -
Hideaki KINOSHITA, Yoshihisa SUDA, Takamasa KAWAKUBO, Toshiaki USUI, T ...1994 Volume 43 Issue 9 Pages 709-714
Published: September 05, 1994
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSA dialysis membrane-covered plastic formed carbon electrode which has been newly developed produced reproducible steady-state currents due to the oxidation of NADH at potentials more positive than 0.2 V (vs. SCE). The limiting currents due to NADH were in the range of 0.30.5 V in solutions of pH 5 to 9 and proportional to the NADH concentration in the range of 2.5 to 1500 μM. The relative standard deviation for the measurement of limiting current due to 200 μM NADH was 2.6% for five runs. NADH reacts with oxaloacetate produced from aspartate by an aspartate aminotransferase (AST) catalyzed reaction in the presence of malate dehydrogenase (MD) and reacts with pyruvate produced from alanine by an alanine aminotransferase (ALT) catalyzed reaction in the presence of lactate dehydrogenase (LD). Based on the magnitude of the current due to 1 μM NADH being 0.17 nA, the activities of AST and ALT in serum were assayed by measuring the decrease in current due to NADH for five min in Tris buffer of pH 7.8 containing aspartate, 2-oxoglutarate and MD for AST assay and buffer of pH 7.5 containing alanine, 2-oxoglutarate and LD for ALT assay. The activities determined amperometrically for seventeen serum samples were in excellent agreement with those determined by the UV-enzymatic method. Correlation coefficients between the two sets of results were 0.996 for AST assay and 0.992 for ALT assay.View full abstractDownload PDF (905K) -
Toshiaki NOMURA, Yoko SHIBUKAWA1994 Volume 43 Issue 9 Pages 715-718
Published: September 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSThe single drop method using an electrodeless piezoelectric quartz crystal (PQC) was able to be applied to the determination of oxalate, in the form of calcium oxalate, in spinach extract. Setting an electrodeless quartz plate, which was treated with paraffin, on the copper plate electrode in a cell, a drop of 5 μl of calcium chloride solution containing potassium chloride and acetate buffer was applied. A platinum wire of a counter electrode was inserted into the drop at 1.0 mm distance between the plate and the top of the wire electrode, and the system was left until the oscillation frequency of the electrodeless PQC became constant. The oxalate sample solution of 5 μl containing potassium chloride and acetate buffer was then added to the drop. By reading the frequency change between just after the application of the sample solution and at 3 min later, the concentration of oxalate was estimated. Oxalate in spinach leaves was extracted with hot water by boiling for 20 min. After passing through a filter paper, the extract was added to acetic acid and incubated over night. Then the extract was filtrated using a membrane filter, and to it was added potassium chloride and sodium acetate to adjust the pH to 4.6. This solution was used as the sample. The concentration of oxalate in the spinach leaves estimated by this method was in agreement with that obtained by ion chromatography.View full abstractDownload PDF (656K) -
Satoshi NOMURA, Koichi NOZAKI, Satoshi OKAZAKI1994 Volume 43 Issue 9 Pages 719-722
Published: September 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSIn order to expand the advantages of fast scan voltammetry, a carbon fiber ultramicrodiskelectrode with low electrode impedance was fabricated. We confirmed that the electrode was suitable for fast response electrochemistry. When applied to fast scan cyclic voltammetry, this electrode enabled measurements which are impossible by normally used platinum ultramicrodiskelectrodes, such as reduction of 2, 2'-bipyridine. Also fast scan stripping voltammetry was established.View full abstractDownload PDF (671K) -
Hiroshi KAWAMOTO, Hideyuki ITABASHI, Tomoyuki OHNUKI1994 Volume 43 Issue 9 Pages 723-726
Published: September 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSBased on the hard and soft acids and bases (HSAB) principle, a method for extraction of metal ions with dithizone was developed for preconcentration and separation of trace metal ions. The extracted metal ions in organic phase were back-extracted to EDTA solution. The resulting solution was applied to isotachophoretic analysis. The separation of zinc(II), cadmium(II) and lead(II) at the 10-6 mol dm-3 level could performed by the present method.View full abstractDownload PDF (666K) -
Jun KOBAYASHI, Kensuke ARAI1994 Volume 43 Issue 9 Pages 727-730
Published: September 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSDownload PDF (717K)
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