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Volume 24, Issue 11
Displaying 1-16 of 16 articles from this issue
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Tsuyoshi NOMURA, Genkichi NAKAGAWA1975 Volume 24 Issue 11 Pages 673-677
Published: November 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSAlizarin complexone (ALC) gives two a.c. polarographic waves, and the first wave has a tensammetric nature. This tensammetric wave appears sensitively in the ALC concentration above 5×10-7 M, and disappears quantitatively by the chelate formation with metals. Within the pH range from 2.5 to 8, the wave height remains constant, and its relation with the concentration of ALC is linear up to 5×10-5 M.
When nickel ion is added to a slightly alkaline solution containing cyanide ion, a stable nickel complex Ni(CN)42- is formed, and the excess nickel ion is titrated with ALC. The end point can be detected by a remarkable increase in the height of the tensammetric wave which appears after the equivalence point of the nickel ion.
The procedure for the determination of cyanide ion is as follows: To a slightly alkaline solution containing (1070)μg of cyanide ion, 1 ml of 10-3 M nickel solution and 10 ml of 0.2 M sodium acetate acetic acid buffer added. The pH is adjusted to about 6.5 with sodium hydroxide or acetic acid, and the solution is diluted to 50 ml with water. This solution is transferred into a titration cell and titrated with 10-3 M ALC.
The effect of diverse ions on the determination of 37.5 μg of cyanide ion was studied. Nitrate, acetate, sulfate, perchlorate and carbonate do not interfere, whereas small amounts of heavy metals, 5×10-5M<Ag+, 10-4M<Br-, I- and SCN-, 5×10-4M<Cl-, 10-3 M<S2O32-, 5×10-3 M<SO32-, 10-2 M<BO33-, NO2-, Ca2+ and Mg2+ do.View full abstractDownload PDF (915K) -
Takao YOGO, Genkichi NAKAGAWA, Kazunobu KODAMA1975 Volume 24 Issue 11 Pages 677-681
Published: November 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe spectrophotometric determination methods of ferrocyanide in the form of prussian blue or the ferricyanide ion with manganese(III) are not sensitive. The pyridine-benzidine, pyridine-pyrazolone, or mercuric thiocyanate methods applied to hydrogen cyanide after isolation by distillation are time-consuming. When the stability constant of ferrocyanide ion (log β6=24 or 36.9) is compared with that of ferroin. ion (log β3=21.3, logK1=5, and log K3=9.85), it is reasonable to expect that ferrocyanide ion could be converted into ferroin ion in the presence of a large excess of 1, 10-phenanthroline. However, the reaction proceeds very slowly. In order to accelerate the reaction, heating, irradiation of ultraviolet rays, and addition of mercuric ion, mercurous ion, or mercury were examined. Heating in the presence of mercuric ion gave the best result. Ferricyanide ion could be decomposed more easily by the same method. The following procedure is recommended. Transfer an aliquot of the sample solution (containing not more than 200μg of ferrocyanide ion) to a small eggplant type flask. Add 1 ml of 1% ascorbic acid, 2 ml of 0.5 M 1, 10-phenanthroline in 1 M acetic acid, and 0.5 ml of 10-3 M mercuric chloride. Adjust the pH of the solution to 24 with diluted sodium hydroxide or sulfuric acid, and heat in a boiling water bath for 20 min. Transfer the solution to a 10 ml volumetric flask, and dilute to the mark with water. Measure the absorbance at 510 nm using reagent blank as the reference. Ferricyanide ion can be determined by the same procedure, except the heating time of 10 min instead of 20 min. The calibration curve is prepared using the solution of Mohr's salt by the same procedure without heating. The proposed method is simple and sensitive, and is useful for the determination of ferro- and ferricyanide ions, either or both, in waste water.View full abstractDownload PDF (848K) -
Masako MAEDA, Kaoru MATSUOKA, Akio TSUJI1975 Volume 24 Issue 11 Pages 681-685
Published: November 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSLumogallion is used as fluorescence reagent for aluminum (III) ion. Basic drugs could be extracted as ion pairs with lumogallion from aqueous acidic solution, and then determined fluorophotometrically after addition of aluminum (III) ion.
Various conditions were examined to determine the optimum condition. The proposed method is as follows. Determination of chloropromazine hydrochloride; To a 20 ml test tube are added 0.5 ml of chloropromazine hydrochloride solution (concentration: 010μg/ml), 2 ml of 0.01% lumogalion solution and 6 ml of 1, 2-dichloroethane. The mixture is stirred for 1 min. by a mixer. After standing for a few minutes, the upper aqueous phase is removed, and exactly 4 ml of organic phase is transferred to another test tube containing 0.5 ml of 0.5% Al(NO3)3 methanol solution. After mixing, and then standing for 30 minutes at room temperature, the fluorescence intensity is measured at excitation (490 nm) and emission (555 nm) maxima. The reagent blank is run through the whole procedure. The interference by various compounds was examined and found not to be important in most cases. This method can be applied to the determination of pharmaceutical preparations. For example, chloropromazine hydrochloride (tablet) was extracted from a tablet with 0.05 N HCl in methanol and then measured by the above procedure. The coefficients of variation (5 determinations) were (0.130.38)%.View full abstractDownload PDF (755K) -
Ichiro TAKEDA1975 Volume 24 Issue 11 Pages 686-691
Published: November 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSRetention values of various samples read on chromatograms are transfered to logarithmic values on section paper using a logarithmic scale, and then read out as retention index values using equally divided scale. By sliding the scale, relationship between carrier gas flow rate and the retention values can be obtained, and relative retention values also calculated easily. For the description of the retention values, all the substances already recorded on the section paper can be used as an internal standard. Qualitative analysis is performed by comparing the peak position of the unknown sample containing an internal standard with that already recorded.
Peak shapes of a certain number of effective plates can be expressed as equal width triangle. So, separation of peaks can be estimated merely by drawing a triangle of the number of effective plates at the position of the peaks on the section paper.
The method is simple, but more useful than usual numerical expression.View full abstractDownload PDF (1031K) -
Masaomi TSUCHIYA, Hirooki SASAKI1975 Volume 24 Issue 11 Pages 691-694
Published: November 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSMethod for the spectrophotometric determination of iron with 6-hydroxy-5-nitroso-1, 2, 3, 4-tetrahydro-2, 4- pyrimidinedione (HNPD) was studied. HNPD reacts with iron (II) to form a water-soluble blue complex easily, but insoluble into such non-polar solvent as benzene and carbon tetrachloride. The iron(II) HNPD complex has an absorption maximum between 630 and 640 nm against a reagent blank and shows a definite absorbance over the pH range from 8.5 to 10.2. The calibration curve shows that Beer's law holds over the range of 050 μg/10 ml of iron(II) at 630 nm, the molar extinction coefficient of the complex and the sensitivity of determination being 1.96 × 104 cm-1 mol-1 1 and 2.6 × 10-3 μg cm-2 for log (I0I/) = 0.001, respectively. Large amount of copper and cobalt interfered with the determination, but the other common ions did not interfere. The molar ratio of iron(II) to HNPD was confirmed to be 1: 1 by using the mole ratio method. The procedure for determination of iron was established as follows. Take a sample solution containing up to 50μg of iron in a 10-ml volumetric flask and add 1 ml of 3% ascorbic acid solution, add 5 ml of 0.4% HNPD solution, 2.0 ml of 2 M ammonium chloride buffer solution (pH 9.2), dilute to the mark with distilled water. Measure the absorbance at 630 nm against the reagent blank obtained in the same way.View full abstractDownload PDF (633K) -
Yukio ONO, Shigeyuki TANAKA1975 Volume 24 Issue 11 Pages 694-699
Published: November 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA new elution method was developed for the separation of additives in lubricating oils and additives concentrates using silica gel or alumina as adsorbent. The experiment was carried out using soxhlet extractor equipped with a extracting tube, 30 mm od and 188 mm long, filled with 50 g of activated 100 to 200 mesh silica gel or alumina. A l g sample of oil is transfered to the top of the column and petroleum ether is circulated through the column continuously.
In the case of silica gel, recoveries of base oils were more than 99% for neutral oils and about 98% for bright stock oils by circulation of petroleum ether for 16 hours. Adsorbed materials on silica gel were the same resinous constituents as found in the compositional analysis of lubricating base oils. However, adsorptivity of aromatic hydrocarbons on alumina was markedly increased. The recoveries of base oils for neutral oils were about 98% and for bright stock oils were 92% to 94%.
Moreover, these methods were examined for the separation of 23 additives commercially available. Almost additives except viscosity index improvers such as polymethacrylate were separated from base oils by continuous elution column chromatography.
It was found that the method was applicable to collective determination of base oils in lubricating oils and to concentration of the additives for the identification by instrumental methods.View full abstractDownload PDF (1033K) -
Yasumasa SHIGETOMI1975 Volume 24 Issue 11 Pages 699-703
Published: November 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA new technique of interfacial co-precipitation by the electrolysis was applied to concentrate micro component in sea water. This utilizes the liquid-liquid interface as a fixed phase and magnesium hydroxide as carrier. Two liters of the solution containing sodium chloride, magnesium chloride and micro amount of iron(III) was put into contact with 500 ml of isobutylalcohol. A stainless steel plate with a diameter of 14 cm was placed in the alcohol phase as the cathode and a platinum wire in the aqueous phase as the anode. The electrolysis was performed at constant current with courrent density of (0.20.8) mA/cm2.
By this process, about 95% of iron at the concentration of 10-5 M was precipitated with magnesium hydroxide at the interface, while only 0.5% of iron was precipitated at 10-4 M.
Generally, when low concentration of sodium chloridemagnesium chloride solution was used, iron was effectively recovered. Current density did not affect the recovery of iron. Furthermore, the method was compared with the co-precipitation by ammonia. Iron can be collected with a less amount of magnesium hydroxide by the electrolysis than that used by a common co-precipitation. In the present case, the adsorption of iron to the alcohol-water interface takes place and the co-precipitation with magnesium hydroxide occurs at the interface.View full abstractDownload PDF (794K) -
Yoshinori TAKATA, Kunio HIROTA, Yoshijiro ARIKAWA, Kaoru SAKAI1975 Volume 24 Issue 11 Pages 703-708
Published: November 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSIn order to concentrate desired constituents and to eliminate interferences, a method for electrolytic pretreatment of sample solution for atomic absorption analysis was investigated. The method is based on constant potential electro-deposition followed by dissolution. In a flow electrolysis cell, heavy metal ions in large volume of a sample are electrolytically. deposited, then the deposits are electrolytically dissolved into a small volume of an eluent.
Recovery after the pretreatment with the cathodic deposition and the anodic stripping of metal ions from the sample solution was almost 100% for Cu2+ and Ag+ when pH value was 0 and also for Cd2+, Pb2+, Zn2+, Co2+ and Ni2+ when pH value was higher than 23. Presence of ligands such as EDTA, however, prevented the deposition by cathodic reduction of the base metals. On the other hand, an anodic deposition and cathodic dissolution was thought to be useful to a sample containing Pb2+ and Mn2+. With these electrochemical methods, analysis of 1 ppb to several hundred ppm of heavy metal ions in the sample solution was possible.
The method was applied to the determination of heave metal impurities in chemical reagents and others. Commercially available sodium dihydrogenphosphate was found to contain 0.13 ppm Pb, 0.03 ppm Cu and <0.01 ppm Cd. The concentration of Zn, Pb, Co, Cu, Ni and Cd in sodium chloride and Cu in brine were also determined. The result shows that the method is successful for atomic absorption analysis.View full abstractDownload PDF (997K) -
Yukio KANDA, Hideo ISONO, Hiroshi KOZUKA1975 Volume 24 Issue 11 Pages 709-713
Published: November 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA radiochemical neutron activation method for the determination of trace amounts of arsenic and antimony in human hair samples is studied.
The sample of hair (100 mg) irradiated for 5 hours with a neutron flux of 2.1 × 1012 n/cm2 s was decomposed with a sulfuric-nitric acid mixture after addition of each 5 mg of arsenic and antimony as carrier. Arsine and stibine were evolved from the solution of decomposed hair by reduction with 3 g of granular zinc and were absorbed in 0.1 N iodine solution for half an hour. Metal arsenic was separated from iodine solution by precipitation with sodium hypophosphite, followed by precipitation of antimony as sulfide with thioacetamide. These precipitates were dissolved and their gamma-ray spectra were measured with a well type 3" × 3" Nal(TI) detector equipped with a 200 channel pulse-height analyzer. After the measurement of gamma-ray spectra, the chemical yields were determined by colorimetric methods. The relative standard deviations were 7% and 4% for 0.01 μg As and 0.024 μg Sb, respectively. The sensitivity of this method was estimated to be 1 × 10-3 μg for arsenic and 2 × 10-3 μg for antimony.View full abstractDownload PDF (836K) -
Wataru YOSHIMURA1975 Volume 24 Issue 11 Pages 714-718
Published: November 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe square-wave polarographic determination of copper by means of coprecipitation with zirconium hydroxide was previously reported {This journal, 23, 1005 (1974)}. The author has investigated polarographic determination of trace amounts of tin by means of coprecipitation with zirconium hydroxide. A squarewave polarograph of Shimadzu type PR-50 was used, and the mercury pool at the bottom of the electrolytic cell was used as an anode. To a solution (20 ml 1000 ml) containing 0.60 μg3.15 μg of tin is added 32 mg of zirconium oxychloride and pH is adjusted to 9.59.7 with ammonia water. The precipitate is separated by filtration and dissolved in 25 ml of 4 M hydrochloric acid. The solution is diluted to 50 ml with distilled water. A portion of this solution is submitted to the polarographic determination. The results are as follows :
(1) A linear relationship exists between the tin concentration and the wave height over the range of 0.60 μg3.15 μg of tin.
(2) Zirconium hydroxide is best effective in collecting tin when pH is adjusted to 9.59.7 with ammonia water.
(3) Effect of various kinds of foreign ions is examined. Lead, bismuth and thallium ions interfere remarkably.
(4) The coefficient of variation of this method was 0.69%.
(5) The analytical procedure took about 3 hours and 0.005 ppm of tin in a sample solution could be determined.View full abstractDownload PDF (643K) -
Masato AIHARA, Mitsuo KIBOKU1975 Volume 24 Issue 11 Pages 718-722
Published: November 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSPotassium benzylxanthate(KBzX) reacts with many metal ions to form chelate compounds which are easily extracted with methylisobutylketone (MIBK). This paper describes a method for the determination of chromium(VI) by the forgoing solvent extraction and atomic absorption spectrophotometry. The procedure was as follows; To sample solution containing up to 30.0 μg of chromium(VI) in a 50-ml separatory funnel, add 5 ml of 10% ammonium acetate buffer. If necessary, after adjusting the pH in the vicinity of 5.5 with diluted hydrochloric acid or aqueous ammonia, add 10 ml of 3% KBzX solution, and extract Cr-BzX with 10.0 ml of MIBK by shaking for 3 minutes. Aspirate the MIBK phase in the flame.
The interference of Cd(II), Pb(II), Hg(II), Cu(II) and Ni(II) with the determination of chromium(VI) at a 100-fold excess were eliminated with the addition of EDTA or o-phenanthroline as a masking agent. The 100-fold amount of chromium(III) gives no interference on the determination of chromium(VI). The optimum pH regions for the extraction were 4.07.0 for Cr-BzX, and were narrowed when using potassium amylxanthate or butylxanthate as a chelating agent. Though the sensitivity of this method was 0.022 μg/ml/1% As without scale expansion of spectrophotometer, it was superior to the DDTC method in diminishing the coefficient of variation of analytical results. With the method proposed here, chromium(VI) in a waste water was determined satisfactorily.View full abstractDownload PDF (648K) -
Tsutomu MATSUO, Junichi SHIDA, Masanobu ABIKO, Kazuhisa KONNO1975 Volume 24 Issue 11 Pages 723-725
Published: November 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSMasking a large amount of Cr(III) with EDTA, micro amounts of Cr(VI) were extracted into methyl isobutyl ketone (MIBK) as diethyl dithiocarbamate (DDTC) complex and analyzed by atomic absorption spectrophotometry.
(a) Determination of Cr(VI): Take a sample solution {containing less than 50 μg of Cr(VI)} into a 100 ml beaker, add 10.0 ml of 0.2 M EDTA solution and boil for 5 min. After cooling to room temperature, adjust the pH value to 45. Transfer the solution to a 100 ml separatory funnel, add 2.5 ml of 2% DDTC solution and make the total volume of it to 50 ml with distilled water. Add 10.0 ml of MIBK and shake the solution vigorously for 5 min. Wash the stopper of the separatory funnel with samll quantities of water and stand for 10 min. Separate the layers and measure the Cr concentration in the MIBK extract with a Hitachi model 207 atomic absorption spectrophotometer, using air-acetylene flame (analytical line; 3579 Å). The extractability of Cr(VI) was 74.8%. The respective presence of less than 5-fold Bi(III), 20-fold Co(II), 10-fold Fe(III) and 5-fold V(V) of Cr(VI) did not interfere. (b) Determination of total Cr: Take a sample solution (containing less than 20 mg of Cr) into a beaker, add 2 ml of (1+4) H2SO4. Add 0.01 N KMnO4 solution dropwise while heating until the solution becomes faintly pink, and boil for 5 min. After cooling, dilute to constant volume with distilled water. Then, take a given volume (containing less than 40 μg of Cr) of the solution, adjust the pH value to 45 Transfer the solution to a 100 ml separatory funnel and determine amounts of Cr as the procedure (a) after addition of 2% DDTC solution. The extractability of Cr(VI) in this case was 98.1%.
Amounts of Cr(III) were calculated from difference between those of total Cr and Cr(VI). The relative error was +3%.View full abstractDownload PDF (601K) -
Studies on oxygen determination by carrier gas methods. XKazuo IMAEDA, Takeo KURIKI, Keiko OHSAWA1975 Volume 24 Issue 11 Pages 725-727
Published: November 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSOxygen in nickel compounds was determined by the Unterzaucher method.
Nickel perchlorate, organic-acid salts of nickel, such as nickel formate, nickel acetate and nickel oxalate, and nickel complexes and organic nickel compound, Such as bis(2, 3-butanedione dioximato)nickel, bis (2, 4-pentane dionato) nickel, hexaammine nickel diperchlorate and tetraaquo (2, 2'-bipyridine) nickel sulfate were used as samples. Oxygen in these samples was determined precisely by the usual method.
Oxygen in nickel chloride with crystal water was also determined precisely by the same method. On the other hand, the amount of oxygen in nickel oxide, nickel nitrate and nickel sulfate was(517)% less than the calculated value.
For the compounds whose total oxygen could not be determined precisely with the usual method, the authors designed the carrier gas method using reaction agent. In this paper naphthalene was used as reaction agent. The results of oxygen determination in nickel oxide, nickel nitrate and nickel sulfate were in good agreement with those of their calculated values with this method. About 40 min was required for one determination.View full abstractDownload PDF (583K) -
Junichi AKIYAMA, Tosie MIZUNO1975 Volume 24 Issue 11 Pages 728-729
Published: November 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA syring-type counterflow device for isotachophoresis has been developed to separate ions that differ only little in mobility. The device was installed in a Shimadzu Isotachophoretic Analyzer IP-1, in order to study the effects of the counterflow on the separation efficiency. The migration current was set to 100 μA; the capillary tube was 50 cm long; the sample was a mixture of aqueous solutions of 0.01 M sodium oxalate, 0.01M sodium formate and 0.01M sodium citrate. The rate of counterflow was varied in 6 steps of 6, 12, 25, 50, 100 and 200 μl/h, by changing the plunger speed. Thus, separation efficiency has been studied as a function of sample volume and counterflow rate. A mixed zone of formate and citrate was observed for a sample volume above 8 μl when counterflow was not applied. This mixed zone was eliminated when counterflow was applied at 200μl/h for 15 min. The effective length of the capillary tube can be increased by 40% by applying a counterflow.View full abstractDownload PDF (256K) -
Tadashi SHIRAIWA, Hiromu IMAI1975 Volume 24 Issue 11 Pages 730-732
Published: November 10, 1975
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA method for the determination of the enol form of various β-diketones in ethanol was established by modifying Meyer's method. An ethanol solution of bromine of about 4 times for the sample concentration was added to the sample solution which was kept at a constant temperature. After standing for an optional time, 0.1 M β-naphthol in ethanol was added until complete decoloration of the solution. The solution was brought to a room temperature, and 10 ml of 10% aqueous solution of potassium iodide was added. The apparent enol content including the enol form produced by the shift of the keto-enol equilibrium was determined by the titration of the liberated iodine with 0.1 N sodium thiosulfate. To subtract the enol form produced by the shift of the equilibrium, the apparent enol content measured was plotted against the standing time. The enol form originally present in ethanol was then estimated by extraporating the linear portion of the resulting curve to the standing time "zero".View full abstractDownload PDF (342K) -
Hiroki HARAGUCHI, Naoki FURUTA, Etsuro YOSHIMURA, Keiichiro FUWA1975 Volume 24 Issue 11 Pages 733-735
Published: November 10, 1975
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSAbsorption spectrum of sodium chloride in an airacetylene flame has been measured in the ultra-violet and visible regions. A Shimadzu AA 650 atomic absorption spectrophotometer was used in connection with a Shimadzu-Yasec Spectral Band Analyzer, which is a data treatment system with magnetic tapes. Although the atomic absorption spectrophotometer is of a double beam type equipped with a deuterium lamp, the absorption spectra measured with this spectrophotometer is non-linear and contains the background due to the aspirated solvent and/or the components of the flame. The spectral band analyzer was used for the correction of the baseline and the background absorptions.View full abstractDownload PDF (493K)
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