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Volume 24, Issue 6
Displaying 1-16 of 16 articles from this issue
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Application of the zone melting technique to metal chelate systems. VIIIShigeru MAEDA, Hiroshi KOBAYASHI, Keihei UENO1975 Volume 24 Issue 6 Pages 327-332
Published: June 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSSeparation of metal acetylacetonate mixtures by zone melting chromatography (ZMC) was investigated on a 2-methoxynaphthalene column. A ZMC apparatus was the homemade one, with which the zone length was controlled constant at 5.0 mm by hot and cold air blasts. A column of 4.0mm in diameter was placed slantwise by 30°from the horizontal line and molten zones travelled at 27mm/hr downwards along the column. Distributions of the solute components after a ZMC process were determined by atomic absorption spectrophotometry for metals or two-wavelength spectrophotometry for metal chelates.
Distribution coefficients determined by Sorensen's method, ksor, varied with the kind of a central metal atom, though depending considerably upon the concentration of the metal chelate. With an increase in the concentrations of solutes in a mixture, the ksor value of each component varied so as to be closer to each other, and ZMC separation became less efficient.
Relationships between the distribution coefficient and the ratio of the half-peak width to the peak position were numerically evaluated. By use of the relationships an observed ZMC curve was analyzed to afford an effective distribution coefficient, k', which though being as half little as the ksorvalue in magnitude, gave a theoretical distribution curve in good agreement with the observed one.View full abstractDownload PDF (1034K) -
Kazuko FUJII, Takashi KUSUYAMA, Kazuo KONISHI1975 Volume 24 Issue 6 Pages 332-336
Published: June 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSChromium (VI)-cupferron complex is extractable into chloroform from (0.030.04) N sulfuric acid media, whereas chromium (III) remains in the aqueous layer. The selective determination of chromium (III) and (VI) was carried out by using this phenomenon. Procedure: To 45 ml of the sample solution containing 10 μg of chromim (VI) in 0.03 N H2SO4, 5 ml of 6% cupferron solution was added, and the resulting solution was shaken with 10 ml of chloroform. To the aqueous layer 5 ml of 6 N H2SO4and 5 ml of concentrated nitric acid were added, and then the combined solution was heated for 5 minutes and adjusted to pH 7 with NaOH solution. Seven ml of 2 N H2SO4 and 2 ml of 0.1% KMnO4 solution were added, and the resulting solution was boiled for 5 minutes. After cooling to the room temperature, 10 ml of 20% urea solution was added and 10% NaNO2 solution was added dropwise until the color was extinguished. The solution was diluted to 70 ml with water and mixed with 1 ml of 1% diphenylcarbazide solution. After standing for 2 minutes, 15 g of NaCl and 10 ml of benzyl alcohol were added to the solution. The resulting solution was shakers vigorously for 30s, and then the organic phase was dried over anhydrous Na2SO4 and the absorbance was measured at 552 nm against the reagent blank. The total chromium {Cr(VI)+Cr(III)} was determined by the same way after reducing with L-ascorbic acid and the amount of chromium (VI) could be calculated by the difference between the total chromium and chromium (III). In this way 100 times amount of iron (II), mercury (II), and molybdenum (VI) and 10 times amount of vanaditun (V) did not interfere with the determination of chromium.View full abstractDownload PDF (936K) -
Masayo MUROZUMI, Yuuji ABE1975 Volume 24 Issue 6 Pages 337-342
Published: June 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA minute amount of copper can be accurately determined by mass spectrometry using a single rhenium filament as a surface ionization device, on which copper compound spiked with 65Cu is loaded. Measurements of 63Cu+ and 65Cu+ ion beam intensity allow to determine the copper amount at(10-110-3)μg level. Add 4μg of 65Cu spike to the samples acidified with hydrochloric acid. Let a pair of spiked samples stand for 3 days and another pair for 4 months. Extract copper as dithizonate in chloroform and evaporate it together with nitric and perchloric acids and finally with sulfuric acid. Dissolve the residue in 0.1 g of redistilled water. An aliquot of the solution is loaded onto the ionization filament, silica gel and phosphoric acid being added as stabilizing agents. The detection limit of Hitachi mass spectrometer is 10-19 A for Cu+ion beam. The ion beam from spiked 65Cu usually gets 10-15 A level of the intensity which is maintained stable for hours. 63Cu+/65Cu+ value is recorded with the coefficient of variation of 0.5%. Copper concentration in sea water determined from the 3-days standing pair samples is (0.38±0.02) ppb and that from another pair is (0.42±0.02) ppb.View full abstractDownload PDF (935K) -
Hajime MATSUSHIMA, Tadaaki WAKIMOTO, Ryo TATSUKAWA1975 Volume 24 Issue 6 Pages 342-345
Published: June 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSCoprostanol (5β-cholestan-3β-ol) is one of the major fecal sterols excreted by man and higher animals. This compound is available for an indicator of fecal pollution. Coprostanol and cholesterol extracted with n-hexane were silylated with bromomethyldimethyl-chlorosilane (BMDS) and the reaction products were determined by a gas chromatograph equipped with an electron capture detector. The detection limits are 10 ng/l for coprostanol and 20 ng/l for cholesterol. These limits are 103 times less than those of the conventional FIDGC procedure.
This method is easy, rapid and very sensitive, and is applicable to the determination of trace amounts of coprostanol in sea water for monitoring sea dumping of excretion of man and livestock.View full abstractDownload PDF (531K) -
Study on automatic chemical analysis of steel. VIIAkihiro ONO, Isamu TAGUCHI, Naoharu YAMAGUCHI, Ryutaro MATSUMOTO1975 Volume 24 Issue 6 Pages 346-350
Published: June 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe proposed method utilizes a rosocyanin complex formed by the reaction of boric acid and curcumin without evaporation to dryness. The automatic determination of boron in aqueous solution is performed according to the predetermined program (Fig. 8), after manual injection of a sample solution (2.00 ml) to the reaction vessel. Glacial acetic acid (5.40 ml) and propionic anhydride (13.20 ml) are added and the solution is circulated through the circulating pipe consisting of a bubble remover, an absorbance measuring flow cell, an air blowing tube and a drain valve. Oxalyl chloride (0.81 ml) is added and the solution is circulated for 80 seconds to eliminate water. Sulfuric acid (1.08 ml) and curcumin reagent (3.01 ml) are added and the solution is circulated for 120 seconds to form a rosocyanin complex. After addition of an acetate buffer solution (21.34 ml) for the neutralisation of an interfering proton complex of curcumin, the absorbance of the orange solution is measured at 545 nm. This automatic analysis is sensitive (Fig. 9) and rapid; less than 1.5 μg of boron is determined in 7 minutes. It can be applied to the determination of trace amounts of boron in steel samples, combined with an automatic distillation under development.View full abstractDownload PDF (852K) -
Study on automatic chemical analysis of steel. VIIIAkihiro ONO, Isamu TAGUCHI, Ryutaro MATSUMOTO1975 Volume 24 Issue 6 Pages 351-354
Published: June 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe optimum conditions for the color reaction were obtained as follows from preliminary studies (Figs.26):Nessler's reagent 4.08 ml, solution volume before addition of Nessler's reagent 22.60 ml, and reaction time at room temperature about 30 seconds. The determination of nitrogen in solution is automatically performed according to the predetermined program (Fig. 7), after manual injection of a sample solution to the reaction vessel. The solution is circulated through the circulating pipe consisting of a bubble remover, an absorbance measuring flow cell, an air blowing pipe and a drain valve, after addition of water and Nessler's reagent. After 40 seconds, the absorbance of the solution is measured at 430 nm. Then the solution is drained off and the vessel is completely washed with water. This automatic analysis is sensitive and rapid; less than 50 μg of nitrogen is determined in 2.5 minutes. It may be applied to the determination of trace amounts of nitrogen in steel samples, combined with an automatic distillation apparatus under development.View full abstractDownload PDF (532K) -
Study on automatic chemical analysis of steel. IXAkihiro ONO, Isamu TAGUCHI, Ryutaro MATSUMOTO1975 Volume 24 Issue 6 Pages 355-360
Published: June 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe automatic system (Fig. 1) consists of a sample changer, a dissolution vessel, a distillation vessel, a color reaction vessel, a spectrophotometer and a controller. The automatic determination of nitrogen in steel is performed according to predetermined dissolution (Fig. 4) and distillation-determination programs (Fig. 5). The chipped steel sample on the sample changer is transferred into the dissolution vessel by vaccum suction. Hydrochloric acid (13.23 ml), hydrogen peroxide (4.68 ml) and water (10.38 ml) are added into the vessel to dissolve the sample. Then hydrogen peroxide is decomposed by heating. The sample solution and washings (28.3 ml) are transferred into the distillation vessel, where acid-soluble nitrogen is distilled as ammonia by heating and bubbling after addition of a sodium hydroxide solution (40%, 24.20 ml). The ammonia is carried with air into the color reaction vessel through the condenser and absorbed in water circulating through the pipe (consisting of an air blowing pipe, a bubble remover, a flow cell and a drain valve). The absorbance of the solution is measured at 430 nm after addition of Nessler's reagent (4.08 ml). The analytical results of steel samples (Table 1. 2) were in good agreement with those obtained by the conventional manual method.View full abstractDownload PDF (993K) -
Hiroshi OGURO1975 Volume 24 Issue 6 Pages 361-365
Published: June 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe sensitivity difference of four different chromium compounds and a method for eliminating it were studied.
A Nippon Jarrell-Ash model AA-1 atomic absorption/flame emission spectrophotometer was used fitted with a slit burner for air-acetylene flame and a HETCO total consumption burner for air-hydrogen flame under the conditions shown in Table 1. As shown in Fig. 1, the four chromium compounds gave the same sensitivity at an acetylene flow-rate of 1.7 l/min or less. At faster acetylene flow-rates, each chromium compound gave the different sensitivity. As shown in Fig. 2, the sensitivity difference as also recognized at any hydrogen pressure in an air-hydrogen flame. The relative sensitivities were as follows: (NH4)2CrO4>K2Cr2O7>CrCl3> K2CrO4 (air-acetylene flame) and K2Cr2O7> (NH4)2CrO4 > K2CrO4> CrCl3 (air-hydrogen flame). A method for eliminating such sensitivity difference was studied by the addition of ammonium chloride which yields an intensive enhancement interference on chromium. As shown in Fig. 3, with 0.02 M (air-acetylene flame) and 0.005 M (air-hydrogen flame) ammonium chloride, the absorbance became a substantially constant values. As shown in Figs. 4 and 5, at any acetylene flow-rate and hydrogen pressure, each chromium compound gave the same absorbance in the presence of ammonium chloride. These facts open up the possibility of using any chromium compound as a standard. Also the accurate estimation of the total amount of chromium in a sample solution containing various chromium compounds becomes possible by the additon of ammonium chloride to both the sample and standard solutions. Examples of analytical results are shown in Table 2.View full abstractDownload PDF (754K) -
Studies on the enrichment of trace metals utilizing the coagulation. of soybean protein. ISoichiro MUSHA, Yoshihisa TAKAHASHI1975 Volume 24 Issue 6 Pages 365-370
Published: June 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSAn enrichment of trace metals in water with a coagulated soybean protein and the complex-forming character of heavy metal ions with the soybean protein were investigated by means of emission spectrography. Fixed amounts of soybean milk (collector) and δ-gluconic lactone (coagulant) were added to a sample solution containing various metal ions, and then the mixture was heated to boiling in order to coagulate the protein. The coagulum (soybean curd) separated from the suspension with a centrifuge was burned to ashes with a low temperature plasma asher. Then metals enriched in the soybean curd were determined by means of emission spectrography. The pH of the solution was adjusted to 4.45.0 by adding suitable amounts of δ-gluconic lactone for the complete coagulation of the soybean protein. The proposed method can be applied to the collection and enrichment of various metal ions such as gold, silver, mercury, platinum, cadmium, beryllium, palladium, antimony, gallium, indium, cerium, lanthanum, thorium, yttrium, zirconium, etc. Those metals are not detectable in the original soybean.View full abstractDownload PDF (1024K) -
Yoshiko YANO, Naoko KONO1975 Volume 24 Issue 6 Pages 371-377
Published: June 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe stability of yttrium complexes, HPi+[Y(TTA)4]- and Y(TTA)3·2H2O (HPi+: γ-picolinium cation, TTA: thenoyltrifluoroacetonate anion) in basic acetone solution was studied by PMR spectroscopy. The chemical shift (δ) of α- and β-protons of γ-picolinium considerably shifted towards higher field and approached to the values for free γ-picoline, as either TBP (tributylphosphate) or γ -picoline was added to the acetone solution of HPi+[Y(TTA)4]-. On the other hand, the δ values for all protons of TTA in the complex slightly shifted towards lower field with increasing of TBP and towards higher field as γ-picoline was added. Because of larger δ values for free TTA than for the complexed TTA, the following reactions seemed to occur:
HPi+[Y(TTA)4]-+nTBP_??_Y(TTA)3·nTBP+
HTTA+Pi
HPi+[Y(TTA)4]-_??_Y(TTA)3+HTTA+Pi
These results are well interpreted in terms of the difference between the synergistic effects of the above mentioned organic bases in the solvent extraction. The PMR spectrum of Y(TTA)3·2H2O was not altered by these bases except for the position of water peak, which was shifted by the bases towards higher field as the result of exchange interactions. In the IR spectrum of HPi+[Y(TTA)4]- (in a KBr disk), the stretching vibration of γ-picolinium, N+-H, was observed at 2850 cm-1.View full abstractDownload PDF (1139K) -
Seiji YASUDA, Hitoo KAKIYAMA1975 Volume 24 Issue 6 Pages 377-382
Published: June 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSAbsorption spectra of various salts such as alkali metal salts, alkaline earth dichlorides, and ammonium halides were investigated and absorptions of some molecular species produced in the carbon tube were identified. The aqueous solution (20 μl) containing 1.0 mg/ml of each salt was placed in the carbon tube atomizer and heated in a similar manner to usual flameless atomic absorption method. D2-lamp was used as a continuous light source and argon gas was employed as an inert sheath gas. The spectra were obtained over the range of wavelength 200 to 350 nm.
When alkali halides were feeded, the absorption spectra agreed with those of alkali halide vapors. Therefore, in such cases vapors of the alkali halides were probably produced by the sublimation or vaporization in the atomizer. The spectra of alkali perchlorates were considered to be those of alkali chlorides produced by the pyrolysis of the perchlorates in the atomizer. The absorptions of alkaline earth chlorides below 250 nm were probably due to their gaseous states. Sulfur dioxide was found to be produced by the pyrolysis of alkali sulfates, bisulfates and sulfites in the atomizer. Alkali phosphates and pyrophosphates gave almost identical spectra below 300 nm. Gamma band spectrum of nitrogen monoxide was observed from 200 to 240 nm during ashing at about 330°C for alkali nitrates and nitrites. Ammonia vapor was produced from ammonium halides during drying at about 170°C.
Although the absorptions of alkali carbonates and hydroxides were almost undetectable, the same spectra as those of alkali halides were observed by the addition of ammonium halides to the solutions of alkali compounds. This shows that alkali halides are produced in the atomizer by the addition of halide ions.View full abstractDownload PDF (875K) -
Keiichiro ISHII1975 Volume 24 Issue 6 Pages 383-385
Published: June 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA spectrophotometric determination of pyridine using nonpoisonous potassium thiocyanate instead of toxic potassium cyanide has been deviced. The recommended procedure was as follows.
To 1.0 ml of potassium thiocyanate solution (SCN 70 ppm), 2.0 ml of chloramine T solution (0.08 w/v% in 0.043 M phosphate buffer, pH 6.4) was added. The mixture was kept for 15 minutes in a water bath at 50°C. To this solution each one ml of the neutral sample solution containing pyridine and the 1-phenyl-3-methyl-5-pyrazolone solution (0.1 w/v% in 4 v/v% ethylen glycol monomethyl ether) was added, and the resultant solution was allowed to stand for 45 minutes at 50°C. After cooling in water, the absorbance was measured at 610 nm against a reagent blank. The calibration curve followed the Beer's law in the range of 07 ppm of pyridine in sample solutions. The coefficient of variation is about 0.7% at 6 ppm pyridine. The influence with diverse compounds on the determination were examined.View full abstractDownload PDF (471K) -
Seiichi OHKUMA, Ikuko SAKAI1975 Volume 24 Issue 6 Pages 385-387
Published: June 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe detection depends on a color reaction between aromatic primary amines and glutaconic aldehyde which is formed by hydrolysis of pyridine in ultraviolet light. The procedure for spot test is as follows: One drop of the sample solution in ethanol or pyridine is placed on a filter paper, and the paper is immediately sprayed with a mixture of pyridine-ethanol (1 : 1, by vol.) and irradiated with ultraviolet light. Aromatic primary amines are visualized as yellow, orange, red or violet spots on the slightly yellow background. The limit of detection is (0.10.3) μg. The procedure can also be applicable to the detection of aromatic primary amines on paper or thin-layer plate chromatograms. After development, the chromatograms are immediately sprayed with the pyridine-ethanol mixture and irradiated with ultraviolet light.View full abstractDownload PDF (492K) -
Sueo NISHI, Yoshiyuki HORIMOTO1975 Volume 24 Issue 6 Pages 387-390
Published: June 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSFor the calibration of analytical methods for total mercury in biological materials, a series of standard proteins spiked with various levels of mercury were prepared and their feasibilities as standard materials have been tested. Purified gelatin was chosen as protein material because of its low mercury content and high water solubility. To its aqueous solutions were added known amounts of methylmercury chloride and/or mercuric chloride. The mixtures were freeze-dried and analyzed for total mercury by cold vapor atomic absorption spectrometry after HNO3-HClO4 digestion, HNO3-H2SO4-V2O5 digestion and oxygen combustion. Good agreements between expected mercury levels and analytical values were obtained except the case where mercury was added as methylmercury solely in more than 2μg/g levels. The low recovery of total mercury at higher levels of methylmercury is supposed to be due to partial loss of methylmercury during freeze-drying. With the methylmercury addition less than 1 μg/g or simultaneous addition of mercuric chloride, no loss of mercury was observed even at 2 μg/g of total mercury. The results indicate that the mercury spiked gelatin is feasible as standard material for the total mercury analysis of animal or fish tissue. Standard materials of desired levels of total mercury can be obtained easily.View full abstractDownload PDF (816K) -
Makoto NOSHIRO, Tomio YARITA1975 Volume 24 Issue 6 Pages 390-391
Published: June 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSAn apparatus for measuring the concentration of total organic carbon in water with a PCO2 electrode as a sensor was constructed and its feasibility was studied. The oxygen carrier gas (approximately 300 ml/min) is used instead of air, because nitrogen in air is converted into NOx which interferes with the PCO2 measurement. The sample combustion chamber is maintained at 800°C, whereas the oxidation chamber is operated at 600°C. Two ml of aqueous sample is injected onto a platinum boat in the combustion chamber with a roller pump and evaporated gradually. Carbonaceous materials are oxidized to carbon dioxide with a Pt-Rh catalyst on alumina. Water vapor is removed at room temperature by a cooling trap, and the carbon dioxide is absorbed in 2 ml of 0.5 M NaOH solution. The solution is acidified with 1 ml of 2 M HCl and introduced into a cell, where the potential of a PCO2 electrode is measured. The content of total organic carbon in the sample was calculated from a calibration curve obtained with the standard solution in the same manner. The time required for an analysis is about 8 min, and the precision is about ±20%.View full abstractDownload PDF (370K) -
Hiroki HARAGUCHI, Shozo TODA, Nobuo HIRABAYASHI, Keiichiro FUWA1975 Volume 24 Issue 6 Pages 392-393
Published: June 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA new type Of two-flames double-beam spectrophotometer for flame absorption spectra has been built, which is equipped with a deunerium lamp, a tungusten lamp and a hollow cathode lamp. The apparatus was applied to the measurement of the absorption spectrum in the ultra-violet region {(280320)nm} in the air-acetylene flame with aspirating the aqueous solution of Mg (500μg/ml), and the obtained spectrum is shown in Fig. 1 along with that taken by the one-flame system. In the spectrum observed by the one-flame system, the molecular absorption bands of OH are observed near (280290) and(305320)nm. On the other hand, the absorptions of OH disappear completely, leaving that of Mg at 285.2 nm in the spectrum by the two-flames system. This indicates that the background absorption due to the flame components and the co-existing species in solution can be automatically corrected by the use of this two-flames double-beam spectrophotometer. The two-flames system can also be useful to a certain extent for correcting the change of the baseline due to that of the intensity of the light source.View full abstractDownload PDF (345K)
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