BUNSEKI KAGAKU
Print ISSN : 0525-1931
Volume 22, Issue 7
Displaying 1-31 of 31 articles from this issue
  • Tateru ASAI, Kazunobu KODAMA
    1973 Volume 22 Issue 7 Pages 811-815
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    Titanium forms so stable a ternary complex with hydrogen peroxide and oxine at pH 3.06.3 that the chloroform extract is not immediately decomposed by dilute sulfuric acid. The excess oxine in the organic phase, which interferes the measurement of the absorbance in ultraviolet region, can almost completelywashed out by a single agitation with 2N sulfuric acid solution for two minutes. Thus the sensitivity at 265 nm is eight times as large as at 425 nm. The blank is small and constant, although Hashitani et al. have stated not be so in determinations of palladium and rhodium. Further washing decreases the absorbance. When the concentration of sulfuric acid is increased, the distribution ratio of oxine is remarkably decreased up to 2N and then gradually as shown below. Constant absorbance is obtained with more than 10-3 M hydrogen peroxide and 6 × 10-3 M oxine concentration. The maximum absorption in the ultraviolet region is present at 265 nm. The apparent molar absorptivity is 4.28 × 104, and the sensitivity by Sandell's method is 0.0011 μg Ti/cm2.
    For determination of less than 20 μg of titanium in solution, add 1 ml of 0.6% hydrogen peroxide and 2 ml of 1% oxine acetate solution, adjust the pH to 3.03.5 with dilute sodium hydroxide solution and 10 ml of 1 M acetate buffer solution of pH 3, and dilute to 25 ml with water. Extract with 25.0 ml chloroform, wash with 40 ml of 2 N sulfuric acid in another separatory funnel, filter through dry filter paper, and measure the absorbance at 265 nm. Beer's law is obeyed over the titanium concentration range of 1 to 20 μg/ 25 ml chloroform. About 1 mg amounts of aluminum and copper do not interfere, but cobalt, chromium(III), and iron(III) do. In the presence of iron(III), the organic phase becomes colorless when shaken with 2N sulfuric acid, but fairly large absorbance is observed possibly due to an oxidation product of oxine.
    Slopes of plots of logarithm of the distribution ratio of titanium against logarithm of total concentrations of hydrogen peroxide and oxine are 1.19 and 2.24, respectively, and that against the pH values is 4.02, which indicates liberation of four protons by the reaction. As titanium and oxine have been shown to exist as TiO2+ and H2+Ox under the experimental conditions, the ternary complex is assigned to be TiO(H2O2) (Ox)2.
    2-Methyloxine does not react similarly.
    The distribution ratio of oxine between chloroform and sulfuric acid is 1.2 × 10-2, 4.5 × 10-3, 2.4 × 10-3, 1.0 × 10-3, and 5.5 × 10-4 for 1.07, 2.14, 3.22, 4.82, and 6.43N, respectively.
    Download PDF (586K)
  • Rapid qualitative and quantitative analysis of inorganic microsubstance by a glass ring oven technique. III
    Atsushi CHIBA
    1973 Volume 22 Issue 7 Pages 816-819
    Published: July 05, 1973
    Released on J-STAGE: May 07, 2010
    JOURNAL FREE ACCESS
    Circular filter paper is used in the conventional ring oven technique. In order to increase the sensitivity and to reduce the volume of sample solution a new ring oven of hard glass which makes use of fan-shaped sheets of filter paper is proposed.
    Figure 1 illustrates the semicircular glass ring oven. The ring oven body is a semicircular hollow vessel. The external diameter is 65 mm, internal diameter is 25 mm, and width is 25 mm. The interior side has a groove, whose width is 5 mm and depth is 5 mm. Two semicircular glass plates whose external diameter is 30 mm, internal diameter is 25 mm and thickness is 2 mm are set in this groove. A fan-shaped sheet of filter paper(center angle: 180°, 90°, 72°, 60°, 36°) is placed between the two glass plates, and the whole is set in the groove. Twenty five mililiters of bath-liquid was placed in a 50-ml round-bottom flask, and the liquid was heated by an alcohol lamp. When water was used as bath-liquid, the surface temperature of oven reached 90°C after about ten minutes, and the temperature was constant for more than ten hours. Different surface temperature may be realized by using appropriate organic solvents. The analysis was carried out according to the conventional ring oven technique. By using a fan-shaped filter paper (center angle 36°) the sensitivity as high as ten times that of the conventional technique was obtained, rendering it possible to reduce the volume of sample solution to one tenth. The appropriate volume of sample solution, less than 1.0 μl, was determined according to the center angle of the filter paper used (Table I). The standard rings were prepared on filter paper of the same dimension. The determination was carried out by comparing the ring of the sample to the standard rings. Alternatively, the standard rings may be prepared on circular filter papers.
    In this technique, fourteen ions could be separated into two or three groups. The efficiency of separation was less than the conventional technique using circular filter paper, but it was expected that the efficiency would be increased by the use of appropriate masking and developing reagents and color reagents. The results obtained by the use of the fan-shaped filter paper agreed with those obtained by the use of circular filter paper within 1%.
    The determination could be performed within about five minutes. The present technique is suitable for the detection and determination of a dilute component in simple mixtures.
    Download PDF (647K)
  • Rapid qualitative and quantitative analysis of inorganic microsubstance by a glass ring oven technique. IV
    Atsushi CHIBA
    1973 Volume 22 Issue 7 Pages 819-823
    Published: July 05, 1973
    Released on J-STAGE: May 07, 2010
    JOURNAL FREE ACCESS
    The ring oven technique had been applied to the separation, concentration and determination of nickel in atmospheric particulates. The atmospheric particulates were collected at a rate of 20 to 30 l/min with membrane filter(Toyo TM-80). The analytical apparatus used was a portable glass ring oven, the bath liquid used was 100 ml of water, and the analytical procedure was carried out at 90°C. Preliminary experiments were made in order to determine the suitable considitions for the experiments. The No. 51A filter paper was found to be the best one. Nickel could be developed in a ring form with 0.01 to 0.2N hydrochloric acid. The operation is carried out by using 15 μl of this acid and then once again with 20 μl. No difference in the color intensity of nickel-dimethylglyoxime was recognized if the dimethylglyoxime concentration was in the range of 0.02 to 0.1 M in ethyl alcohol; Thus a concentration of 0.1 M of the reagent was employed throughout the experiments. When this reagent solution was added 4% ammonia water, the process, exposure of the paper to ammonia vapor, could be avoided. The detection limit was 0.03 μg and the determination range was 0.03 to 3.0 μg. Membrane filter was cut in a small disk form (Fig. 1), and a cutting this small disk was contacted in the middle of a piece of filter paper(No. 5lA, 55 mm φ) by directing the sample-bearing surface down and fixed with a drop of aceton. After sulfide is formed on original small disk by passing hydrogen sulfide, the filter paper is setted upon the ring oven placing upside-down. Nickel is eluted out to the ring zone on the filter paper with 0.05 N hydrochloric acid. After iron is masked by treating with 5% citric acid, 0.1 M ethyl alcohol solution of dimethylglyoxime(in 4% ammonia water) was sprayed in order to color nickel and then the paper was dried with a hair drayer. Fifty standard rings have been made by using a nickel standard solution and the amount of nickel in the sample was determined by promptly comparing the intensity of the color with the standard rings. The nickel standard solution used in this experiment contained iron(III) 100 times of nickel. Another analysis technique employed was as follows: The membrane filter is immersed in isopropyl alcohol and burned in an electric furnace at 150 °C. The ash is dissolved in 0.500 ml of 1 N hydrochloric acid and then nickel, is determined by using a semicircular glass ring oven. An amount of nickel, 0.5 to 1.0 μg in the sample could be determined by this technique. When the sample is collected in a residencial area, or when it is humid, a large amount of air should be passed through the paper or otherwise it was necessary to add 0.03 μg of nickel. It was found that to cut the sample filter paper as a disk is more suitable than to cut it as a triangle plate.
    This technique can be carried out within a short time; it took about ten minutes and the limit of error is 5% when it is applied to the determination of nickel in atmospheric particulates. The technique may be also use for polluting substances in atmospheric particulates and in working environment.
    Download PDF (822K)
  • Studies of state analysis with instrumental method. IV
    Kimitaka SATO
    1973 Volume 22 Issue 7 Pages 824-831
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    In the analysis of inorganic powders by means of infrared spectroscopy, it is known that the shape and the intensity of spectrum change due to the particle size of powdered sample. Lejeune (Ref. 9), Duyckaerts (Fig. 9, 10), and Bonhomme (Ref. 11) investigated in detail the relationship between the particle size and spectrum of CaCO3, and clarified that the effect was remarkable. Sato et al. recently showed that the absorption bands of α-SiO2, Si3N4 etc. became stronger and sharper and adjacent bands were finely separated when the particle size decreased.
    In the present paper, the shapes and intensities of infrared spectra were investigated for each α-SiO2 ground with or without graphite powder (as asolid lubricant) in an agate mortar or a vibrating mill, in order to grasp quantitatively the relation of spectrum with the effect of particle size by grinding the powdered sample.
    The results are as follows;
    (1) α-SiO2 can be ground into minute particles after 30 seconds in a vibrating mill, so the adjacent bands are well separated, the absorbances become constant, and their variations are hardly recognized even if the powder is ground further (Fig. 1, 2, and 5).
    (2) On the other hand, in the case of grinding using an agate mortar, the particles of large size remain, so the absorbances tend to increase with the progress of grinding (see Fig. 4).
    (3) The reproducibility of absorbance at 782 cm -1 band was investigated for 10 samples of each ground powder. As the result, it was found that the reproducibility became smaller with the progress of grinding, and the coefficients of variation became about 2% by the grinding of 2 minutes in a vibrating mill or of 22 hours in an agate mortar (see Table I).
    (4) The addition of graphite powder has little effect in grinding by an agate mortar, whereas it has a remarkable effect in the case of a vibrating mill with which powder can easily be ground into particles of uniform size less than 1 μm. It makes clear that graphite adding effect reveals in the intensity and the sharpness of absorption band.
    Download PDF (9183K)
  • Thin-layer chromatography on precoated adsorbents fixed with fused glass. VII
    Tamotsu OKUMURA, Tetsuro KADONO
    1973 Volume 22 Issue 7 Pages 832-836
    Published: July 05, 1973
    Released on J-STAGE: May 07, 2010
    JOURNAL FREE ACCESS
    In a previous paper, we reported the preparation of a new type of precoated plate for thin-layer chromatography which was made by heating a mixture of Kieselguhr and glass powder at a temperature under 750°C for several minutes. Although thermal expansion coefficients of Kieselguhr and glass powder are very much different from each other, the welding of these two substances readily took place. It seemed interesting to us that Kieselguhr, even when heated at such a high temperature, did not lose its chromatographic activity.
    In general, sintering of Kieselguhr is known to begin at 600°C to 700°C as in the case of silica gel. The heating period in our experiments was so short that sintering of Kieselguhr did not seem to take place. There is no information in the literature about the effect of heat on Kieselguhr for thin-layer chromatography at such a high temperature. Therefore, heat treatment of Kieselguhr was studied under various conditions, i. e., at 450°C to 750°C for 2 to 7 minutes. Using the Kieselguhr thus treated, thin-layer chromatographic separation of test mixtures such as polychlorinated biphenyls (decachlorinated biphenyl and Kanechlor 600) and azo dyes (Sudan Red G, Sudan Yellow, Butter Yellow and p-methoxyazobenzene) was performed. Table I shows no change in physical properties of the heated Kieselguhr, and Table IIV indicate the constancy of Rf; values and the good separation of the test mixtures. These results confirm that sintering of Kieselguhr does not occur under the condition described above.
    We have clarified the welding mechanism of the Kieselguhr sintered plate by means of scanning electron microscopic method (the micrographs were taken by using JEOL Model JSM-2 scanning electron microscope). It is evident from photograph 5 that Kieselguhr is fixed among the three dimensional matrix formed by the sintered glass powder and glass plate without loss of its surface structure. Thus sintered glass powder plays a role of binder between Kieselguhr and glass plate.
    Download PDF (6682K)
  • Hiromi ARIMOTO
    1973 Volume 22 Issue 7 Pages 837-843
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    This system of ionization chamber simplifies the analysis by providing simultameous gas chromatography and continuous radioactivity analysis from which specific activity data may be calculated.
    The author manufactured the ionization chamber as a detector for radio-gaschromatography and examined the many characteristics of the equipment. This equipment consists of the ionization chamber, thermostatic oven contained the chamber, and the vibrating reed electrometer. Three kinds of chamber, 270 ml, 150 ml, and 70 ml respectively, were used in the experiment. The system provides a extensive range of operating conditions. Oven temperature of ionization chamber can range from ambient to as high as 300 °C, easily accommodating high boiling compounds such as fatty acid esters, amino acid derivatives and steroids. Activities can be measured from 2 mμ curies 14C (74 dps) or 10 mμ curies (370 dps) to many millicuries per component.
    Excellent resolution is retained by the purge system shown in the system flow passage diagram (refer to fig. 4) in which a purge gas is introduced into the stream prior to its entering the ionization chamber. The purge gas flow may be varied to adjust the turnover time in the chamber. With the 270 ml chamber, the time for complete replacement of the chamber volume can be varied from approximately 1 minute to 20 minutes.
    The purge gas system offers an important merit in that one may select a desirable filling gas for the chamber. The variation in specific ionization (electron volts/ion pair) and density of gases affect the amount of current and chamber efficiency respectively. By using a gas of high density having a low specific ionization (e.g. argon, argon +CH4), the high resolution can be achieved at little or no loss in sensitivity.
    The high temperature ionization chamber is specially designed to retain the high sensitivity and precision of the ionization chamber method at elevated temperatures. The 270 ml volume offers the most desirable compromise in size when the properties of both 14C and 3H, the most common tracer isotopes, are considered. The chamber is constructed of stainless steel and is electrically insulated from the oven by insulators on the gas inlet and outlet lines. The chamber base includes a rigid line connector to and adapter assembly on which the chamber electrode mounts at one end and is connected to the electrometer input at the other. The electrometer input is thermally isolated from the oven by rigid line. The vibrating reed electrometer has the high sensitivity and stability essential for radioactivity measurements of 14C and 3H which involve detection of currents less than 1015 amperes. Input resistor of the vibrating reed electrometer used is 1012 Ω in maximum. Dynamicrange of chamber is 103. Data are given for steroid and higher fatty acid methyl esters.
    Download PDF (904K)
  • Sumio YAMASAKI, Hiroki OHURA, Issei NAKAMORI
    1973 Volume 22 Issue 7 Pages 843-849
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Quantitative determination of chloride, hypochlorite, chlorite, chlorate and perchlorate ion mixtures was studied.
    Hypochlorite, chlorite, chlorate and perchlorate ions were reduced to chloride ions one after another with proper reducing agents, according to the oxidationreduction potential.
    After the reduction, these chlorides could be titrated with a silver nitrate solution by means of shortcircuit amperometry, which uses a rotating platinum wire electrode (1000 rpm) as the indicative electrode and a saturated calomel electrode(SCE) as the reference electrode.
    In the reducing operations, hypochlorite (ClO-) could be reduced within a few minutes by sodium arsenite at pH 810, hypochlorite and chlorite (ClO2-) could be reduced within ca. 10 minutes at room temperature by potassium borohydride at pH 27, and hypochlorite, chlorite and chlorate (ClO3-) by sulfurous acid in acidic region.
    Hypochlorite, chlorite, chlorate and perchlorate(ClO4-) could be reduced by fusing with sodium nitrite for ca. 30 minutes in a nickel cruciple. In the amperometric titration of these chloride solutions, the procedure employed is as follow. pH of the sample solution was adjusted 88.5 with 0.1 N acetic acid solution and 0.1 N sodium acetate solution, and then 10 ml of 1 M potassium nitrate solution (as a supporting electrolyte) and 10 m l of 0.2% gelatin solution was added. Finally the total volume of the solution was diluted to 100 ml with water.
    When the concentration of chloride was ca. 10-4M, 5 ml of 0.1 M barium nitrate and 25 vol% methanol should be added to remove carbonates dissolved in the sample and to decrease the solubility of silver chloride.
    In the case of a sample chloride solution containing ClO- (1st case), or ClO- and ClO2-(2nd case), the chloride could be determined by titration under the following conditions.
    Excess chlorate(ca. 2.5 M) solution had to be added, and the temperature had to be kept below 2°C, as soon as the sample was take in.
    Moreover, for the 2nd case, the concentration of either ClO- or ClO2- had to be held below ca. 10-3 M.
    Because, otherwise, the disproportionation and interactions between these ions occur during the titrating operation and thus the determination becomes difficult.
    In general, the amount of the designated ion can be determined from the difference in the volumes of the silver nitrate standard solution consumed until the end points in two proper titrations.
    By these experiments, the lower limiting concentration range was found to be ca. 10-4 M for each ion and, in these cases, the relative percentage errors were ca. ±3%.
    However, if the ratios of any ion to the other ions are higher than 50 and chloride is titrated by using a certain silver nitrate standard solution, these errors become over ± 10%, as shown in Table I.
    Download PDF (1157K)
  • Yukio NAGAOSA, Tatsuo YONEKUBO
    1973 Volume 22 Issue 7 Pages 850-856
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Molybdoarsenic acid forms precipitate with tetraphenylphosphonium chloride (TPPC) from acid aqueous solution, but when polyvinyl alcohol (PVA) is added to the solution previously, water-soluble complex is formed, which can be used for the spectrophotometric determination of arsenic(V). The calibration curve of arsenic at 400 nm was quite linear over a range of 5×10-64×10-4 M, and the sensitivity was higher than either of the molybdenum yellow or molybdenum yellow extraction method. The recommended procedure for the determination of arsenic was as follows. To a sample solution containing less than 8 μmol of arsenic in a 20 ml volumetric flask, 4 ml of 0.5 M molybdate solution and 3 ml of 10 N nitric acid were added. The whole volume was made up to 14 ml with distilled water, and the solution was kept at 25°C for about 10 min. Then, 5 ml of 5% PVA solution and 1 ml of 0.02 M TPPC solution were added, and the final volume was adjusted exactly to 20 ml with distilled water. The solution was well mixed, and the absorbance (A) was measured at 400 nm within 30 min against the blank. The molar absorptivity of arsenic was 2.20 × 103l mol-1 cm-1. The moleratio of the water-soluble complex was found to be 1 : 1 (TPPC: molybdoarsenic acid) by means of the continuous variation method. The influence of diverse ions on the determination was examined, and it was found that iron(III), nickel(II), titanium(IV) and silicate ions should not be present. Phosphate ion also interfered seriously, but simultaneous determination of the two elements was successfully performed by the following procedure. The absorbance (B) corresponding to the amount of phosphorus in the presence of arsenic was measured at 420 nm according to the same procedure as mentioned above except that PVA and TPPC were not added. The sum of absorbance of arsenic and phosphorus was determined from the absorbance (A). The concentrations of arsenic (CAs) and phosphorus (Cp) were calculated by the following formulas, respectively.
    CAs = k1A - k2B
    Cp = k3B
    where k1= 4.52 × 10-4, k2= 1.69 × 10-3 and k3= 1.62 × 10-3 mol l-1. This method was applied to the synthetic sample solutions containing 1.0 × 10-52.5 × 10-4 M arsenic and phosphorus with good results.
    The water-insoluble precipitate described above was extractable into 1, 2-dichloroethane. Result of the continuous variation method indicated that the mole ratio of TPPC to molybdoarsenic acid in the extracted species was 3 : 1.
    Download PDF (861K)
  • Yasuyuki MAKI
    1973 Volume 22 Issue 7 Pages 856-860
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    The separation of 113mIn from a mixture of 113Sn-113mIn in a radioactive equilibrium was carried out by a thin layer chromatographic method using silicagel as the adsorbent and diluted acetic acid as the developer. At first, the separation of non radioactive Sn(II), Sn(IV) and In(III) ions were tested by using various concentrations of acetic acid solutions. By increasing the concentration of acetic acid, a higher Rf value for In(III) was obtained. On the contrary, Sn(IV) was retained at the original point and Sn(II) advanced with tailing because it was oxidized to Sn(IV) during the development. Accordingly, in order to let Sn stay at the origin, Sn(II) must be oxidized to Sn(IV) by adding H2O2 into the sample solution before the development. The best separation of Sn and In were obtained by the solvent consisting of acetic acid: water (1 : 10), by which the Rf values were 0.00 for Sn(IV) and 0.90 for In(III).
    The spread of Sn (IV) spot was investigated by using sample solutions at various HCl concentration. Sn(IV)spread with increasing the HCl concentration, while In(III) spot stayed at the position of Rf value 0.90 irrespective of the HCl concentration. Accordingly, in order to obtain a clear separation of the spots of these two ions, the HCl concentration of the sample solution must be adjusted at about 1 N.
    The development could be achieved within about 20 minutes by raising the developing solvent 5 cm high from the original point.
    113mIn was separated from 113Sn by applying the method mentioned above. The radiochemical purity of the 113mIn which was scratched from the developed plate was identified to be more than 99.9% by analyzing its decay curve, about 93% of it was extracted from the adsorbent by 5 ml of an acetic acid : water mixture (1:10).
    Download PDF (623K)
  • Masayoshi KIYOKAWA, Akira KAWASE
    1973 Volume 22 Issue 7 Pages 860-866
    Published: July 05, 1973
    Released on J-STAGE: November 18, 2010
    JOURNAL FREE ACCESS
    9-(2-Pyridylazo)-10-phenanthrol, PAP, has been proposed as a sensitive reagent for metal ions in the previous paper. It has been recommended as an extractive spectrophotometric reagent since it has greater formation constants of metal chelates and sensitivities than PAN has.
    More detailed stady is needed concerning the reagent and its metal chelates, because there has been no ditailed study of its behaviour at various pH, equilibrium forms, dissociation constants, metal ligand ratios, formation constants of the chelates in various dioxane concentrations, which are important in analytical chemistry.
    PAP can be regarded as a bibasic acid. The acid dissociation constants of the reagent are determined spectrophotometrically at different dioxane concentrations. The value of pKa1 decreases and that of pKa2 increases with increasing mole fraction of dioxane. The plots of pKa1 and pKa2 against mole fraction of dioxane, n2, are linear. The equations for the straight lines are pKa1=-5.875 n2+2.87
    pKa2=6.497 n2+12.80
    PAP reacts with copper, zinc, and nickel to form red or violet, water-insoluble chelates. The results of the continuous variation method indicate that 1 to 1 chelates of copper and zinc and a 1 to 2 chelate of nickel are formed in dioxane-water mixtures. However, in solution containing more than 100-fold amounts of nickel, PAP forms a 1 to 1 chelate. The formation constants at different dioxane concentrations for the reactions between PAP and metal ions are determined spectrophotometrically. The formation constants increase with increasing mole fraction of dioxane, and the plots of log KRMR for 1 to 1 chelates against mole fraction of dioxane are linear. The equation of the straight lines are given by the equations :
    log KRCuR =7.208n2+ 16.48
    log KRNiR =10.56 n2+12.90
    log KRZnR =8.657 n2+ 10.35
    The distribution coefficient of the reagent between carbon tetrachloride phase and aqueous phase is determined spectrophotometrically. The logarithmic value, log KDR, is found to be 5.06+0.02, which is about 1.1 units greater than that of PAN. This fact suggests that the extension of benzene ring affects the aqueous solubility of the reagent. A study is made of the extraction of the chelate of copper and PAP from water into carbon tetrachloride. Since the slopes of the extraction curves, log [HR]0 vs. log D[H+]2 and pH vs. log D[H+]2-, are both 2. The results indicate that copper react with two molecules of PAP and two protons are released in forming the extractable species. The values of logKex and log KDCβ2 are found to be -1.65±0.02 and 36.13±0.02, respectively.
    Download PDF (805K)
  • Kiyoshi HOSHINO
    1973 Volume 22 Issue 7 Pages 866-872
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    An automatic apparatus has been developed for the rapid and accurate determination of the amount of sulfur in petroleum. In order to obtain accurate results of the sulfur contents, it is essential to burn petroleum sample smoothly without spattering or smoking. This is accomplished by modifying a sulfur analyser for iron and steel, which is based on high-temperature combustion by high frequency (H. F.) induction heating combined with coulometric titration. The characteristics of the analyser are (a) all the gaseous sulfur formed by combustion is carried into the absorption solution without condensing on the wall of the tubing; this is ensured by the use of a special flushing device and of an automatic recirculation and by special technique of heating the tube and (b) the programmed combustion of the sample enabling the smooth burning.
    (1) The best conditions for placing sample in crucible are discussed. The sample is placed in a small cup (oil sampler) and after weighing, the cup with the sample is placed in a crucible and covered with a layer of Al2O3 and then a layer of iron powder.
    (2) A programme control function is added to the H. F. power supply. At the beginning of the combustion, the heating power is set to a low value so that the burning take place at a low temperature. The heating power is then increased gradually until maximum power is reached and maintained.
    (3) The shape of the combustion tube is modified. Instead of using the conventional straight type combustion tube with constricted end, a special combustion chamber with a spiral tube is used. This increases the path in the heated zone, ensuring the complete buring of the fine mist of the sample which escapes from the crucible on combustion.
    With this apparatus the determination can be made automatically with high precision in 815 minutes.The repeatability for the residual fuel oil (mass fraction of sulfur =2.5% S) was 0.85% as coefficient of variation. The values of sulfur contents in petroleum obtained by this method agreed well with those obtained by the standard method.
    Download PDF (960K)
  • Toshiko KIMURA, Hiroshi IWASE
    1973 Volume 22 Issue 7 Pages 872-875
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    Analytical method of fatty acids in a microgram scale was studied.
    Fatty acid in amount of 10100μg in aqueous solution was quantitatively extracted by three times each for 2 min with diethyl ether in a separation funnel by hand. The extractant was dried over anhydrous sodium sulfate over a night. Then the dried extractant was distilled at 4045°C in a water bath to almost dryness.
    Fatty acids were methylated with diazomethane for gas chromatography. A small amount of diazomethane was prepared according to the method of Schlenk et al., and bubbled into methanol-diethyl ether (1: 9 v/v) up to saturated with it.
    The dry residue was treated with an excess of methanol-ethereal diazomethane at room temperature for 30 min, followed to heat at 4045°C in order to remove an excess diazomethane.
    Methyl derivatives were eluted in 22 min using temperature programming from 90°C to 230°C at rate of 7.5°C/min on a glass column 4 ft×1/4 in (o. d.)containing 2.5% stabilized PEGA on Diasolid M (6080 mesh). Concentration was calculated by comparing the peak heights. Calibration curves were linear for each acid in the range of 5 to 100 ppm. The relative standard deviations for the peak heights of fatty acid methyl esters with temperature programming were within 3%.
    Recovery of more than 90% was obtained at esterification of fatty acid using diazomethane, but lower for C8 and C10 acids, because some loss was observed for their volatility at the removal of an excess diazomethane. Recovery of more than 90% for fatty acid was obtained at extraction from the acidic solution (concentration of less than 1 ppm).
    A 2.5% FFAP column was used for identification of fatty acid to the sample which were observed many peaks on a chromatogram, and a 10% PDEGS column was used to separate saturated and unsaturated fatty acids.
    In the case of microanalysis, it was necessary before use to remove the impurities contained in diethyl ether, distilled water, sulfuric acid and anhydrous sodium sulfate used at extraction.
    Download PDF (749K)
  • Yuroku YAMAMOTO, Takahiro KUMAMARU, Yasuhisa HAYASHI, Toshihiko KAMADA
    1973 Volume 22 Issue 7 Pages 876-881
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    An atomic-absorption spectrophotometric method for the rapid, sensitive and precise determination of arsenic with arsine-argon·hydrogen flame system has been developed. Various factors effected on the evolution of arsine from ppb level of arsenic in water are investigated in detail. The arsine could be rapidly evolved from arsenic solution in 2 N hydrochloric or sulfuric acid by using zinc powder tablets together with potassium iodide and stannous chloride solutions as the reductant. The role of potassium iodide and stannous chloride in the reduction process of both arsenic(III) and arsenic(V) was made clear as follows: (1) Both the potassium iodide and stannous chloride enhance to a large extent the recovery of arsenic as arsine, and the same values in atomic-absorption signal can be obtained either from trivalent arsenic or pentavalent arsenic state, (2) only 90 sec gas sampling time is enough to obtain 100% recovery of arsenic as arsine, (3) the optimum acidity can be lowered and the degree of interference of diverse ions can be reduced to a considerable extent.
    The sensitivity of the method for 1% absorption was evaluated to be 0.7 ppb of arsenic and the linearlity of the absorption vs. concentration was good up to 1 μg/20 ml (50 ppb). The precision was estimated to be 2.6% from the results of ten arsenic solutions (50 ppb). The maximum permissible amount of diverse ions was as follows; selenium(IV) 7 μg, lead(II) 150 μg, antimony(III) 220 μg and sulfide ion 200 μg. The following ions when present in 5 mg level did not interfere with the determination; Na+, K+, NH4+, Ca2+, Mn2+, Cu2+, Zn2+, Ag+, Cd2+, Hg2+, Al3+, Cr3+, Fe3+, Co2+, Ni2+, Te4+, Bi3+, Cl-, Br-, I-, NO3-, NO2-, CH3COO-, CN-, SCN-, MnO4-, Cr2O72-, SO42-, SO32-, MoO42-, WO42-, PO43-, BO33-. Recommended general procedure is as follows: Transfer 20 ml of a sample solution containing not more than 1 μg of arsenic into a reaction bottle. Add 2 ml of 12 N hydrochloric acid, 1 ml of 40% potassium iodide solution and 2 ml of 10% stannous chloride solution. Swirl the solution to mix thoroughly. After adding two piecies of the zinc tablet (about 0.5 g per a piecies), immediately connect the reaction bottle to the collection unit and allow the reaction for 90 sec at room temperature by agitating the mixture with a magnetic stirrer. Turn the four-way stopcock to the “sweep” position in order to introduce argon into the system, sweeping the hydrogen and the arsine into the argon-hydrogen flame. Simultaneously record the absorption signal (1937 Å) on a recorder. Finally return the stopcock to the “bypass” position.
    The method was applied to analyses of water samples with satisfactory results.
    Download PDF (1060K)
  • Tsuguo SAWADA, Hitoshi KAMADA
    1973 Volume 22 Issue 7 Pages 881-885
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    A time-resolved spectrometer was made with a singlephoton counting technique. This instrument is suitable for measuring fluorescence lifetime and transient behavior of fluorescence. And the time-resolved emission spectrum of a spark discharge is also recorded. The light source and fluorescence were dispersed with a small monochromator. In a single photon counting technique, the time of the emission of individual fluorescence photon is measured electronically with Ortec 437 A time to amplitude converter(TAC), the reference time zero being the initial rise of current pulse related in time to the pulsed light. The time-distribution of single photons is accumlated with NAIG D161 and D171 multichannel pulse height analyzer. RCA 8850 photomultiplier was used for detecting single photons. The time-resolution obtained experimentally was about 0.1 nsec. The pulsed light source which is simple to be constructed and its use was developed. This lamp filled with air or hydrogen at 1 atm was opereated in a relaxiation mode at a usual repetition rate of 10 kHz. The decay time and the width of half-maximum as measured with the above apparatus were 0.5 nsec and 1.5 nsec. In the lamp operated in air, most of the emission is between 300 nm and 400 nm, which is primarily from the C3π-B3π transition of nitrogen.
    In this paper, the typical air-filled flash lamp decay and the time-resolved spectrum of the hydrogen flash lamp are shown. The use of the apparatus is illustrated by salicylic acid. At pH4, the fluorescence lifetime was 4.9 nsec, which correspond to that of singly ionized species, whereas in 6 N KOH solution the lifetime of doubly ionized salicylic acid was 3.9 nsec. In organic solvents such as methanol, the decay curve of fluorescence was composed of two exponents. The shorter lifetime was 0.6 nsec and the longer was 4.4 nsec. The shorter lifetime seems to correspond to that of the zwitterion formed due to intramolecular proton transfer in the excited state. The existence of the longer exponent shows that a slight amount of salicylic acid exists as singly ionized species in the ground state.
    Download PDF (558K)
  • Studies on analytical method for prevention of environmental pollution. I
    Toshihiko HATA, Toshio HAGIWARA, Kiyoshi SUMI
    1973 Volume 22 Issue 7 Pages 886-892
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    There is Japanese Industrial Standard : JIS M 8212 for the determination of total iron, in which trivalent iron is reduced with stannous chloride and the excess of reductant is oxidized with mercuric chloride. However, it is known that this method is undesirable in view of the pollution of the drain age by mercury. For this reason, the authors proposed the using of metallic aluminum in place of stannous chloride as reductant of iron. The aluminum reduction method have already been reported by Scott (Ref. 3), Riegel (Ref. 4) and Wakino (Ref. 5), but this method was very restricted. about the application for interference element. Titanium gave a serious error, and this method can not be adapted to samples which contain titanium. For determination of iron in various samples by aluminum reduction method, it was necessary to remove the interference of titanium. In the proposed method, such an interference could be masked by titrating the tungsten blue, which was formed from reduced trivalent titanium and sodium tungstate, with potassium dichromate solution. Subsequently, iron in this solution was titrated with standard potassium dichromate solution.
    Three methods, acid dissolution method, direct fusion method with sodium peroxide and fusion method with potassium phyrosulfate, for the determination of total iron have been experimented. The procedure of acid dissolution method is as follows:
    0.4 g of sample is dissolved with 30 ml of hydrochloric acid in a reducing flask by heating. The solution is diluted to 150 ml with water after adding 10 ml of hydrochloric acid. After addition of 1.5 g of granular aluminum, the solution is heated gently until it is dissolved in nitrogen gas for reduction of ferric iron. The solution is cooled in a cooling water to a room temperature passing the nitrogen gas. 30 ml of the sulfuric acid-phosphoric acid mixture and sodium tungstate solution are added and then the solution is diluted to about 250 ml with cold water. To prevent the interference by titanium, the solution is titrated with 0.1 N potassium dichromate solution until the blue color of the solution is disappeared. Subsequently, bivalent iron in the solution is titrated with standard potassium dichromate solution using the sodium diphenylamine sulfonate as the indicator and iron content is determined.
    Analytical results of raw materials for iron manufacture by this method agreed closely with those by stannous chloride method and standard deviation for hematite, sinter and iron are were 0.04, 0.07 and 0.06, respectively.
    Download PDF (963K)
  • Yoshinori KIDANI, Kenji INAGAKI, Noboru OSUGI, Hisashi KOIKE
    1973 Volume 22 Issue 7 Pages 892-895
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    Chinoform, being a derivative of oxine, forms metal chelate with various metal ions. It is known that chinoform reacts with zinc to produce a yellow chelate of 2:1 ratio and it is extractable with methyl isobutyl ketone (MIBK). Therefore, if zinc in MIBK layer is measured by atomic absorption spectrophotometry, then chinoform may be determined quantitatively. Chinoform zinc chelate can be extracted easily with chloroform, but MIBK is considered to be more suitable than chloroform as a solvent for atomic absorption spectrophotometry.
    In this experiment, a Hitachi 207 Atomic Absorption Spectrophotometer was used, and the 2138 Å analytical line of zinc was used for the measurement using airacetylene flame. The procedure for the determination is described below. Ten ml of 4.1 × 10-5 M chinoform MIBK solution was taken in a 100 ml separatory funnel, and then 10 ml of 2.0× 10-4 M aqueous zinc sulfate solution and 10 ml of sodium borate-boric acid-sodium chloride buffer solution, adjusted at pH 7.9, were added. The mixture was shaken well for 10 minutes and kept standing for 10 minutes. The lower aqueous layer was firstly separated off and secondly MIBK layer was transfered into a test tube. After MIBK layer was filtrated through filter paper, 2 ml of the filtrate was diluted to 10 ml with MIBK, and then the absorbance was measured by atomic absorption spectrophotometry against a reagent blank. From the above investigation, optimum conditions for the extraction have been found.
    Most suitable pH range was found to be 7.4 9.0, the concentration of zinc sulfate was 0.5 20 times larger than that of chinoform and the shaking time was more than 10 minutes. The authors examined how the volume ratio (R) between aqueous layer of the metal ion and the buffer, and MIBK layer influences upon the intensity of the absorbance. Consequently, the intensity was found to be higher as R increased. Throughout this measurement, R=2 was used.
    Under the optimum conditions mentioned above, a good linearity was obtained between absorbance in organic layer and chinoform content in the range of 6.030.0μg chinoform per ml. When the repeat, ability of this method was examined, the standard deviation was calculated to be 0.495. The composition of the chelate extracted was found to be 2 : 1 ratio according to the continuous variation method.
    This method was applied to drug preparations. Chinoform preparation was dissolved in MIBK and insoluble substances in the solution were removed by filtration. MIBK layer was washed with sulfuric acid and then chinoform was extracted as a zinc chelate. Zinc in MIBK layer was measured by atomic absorption spectrophotometry, and this preparation was determined to contain 18.2% chinoform. Recovery was found to be 98.5%, according to the standard addition method.
    Download PDF (606K)
  • Yoshinori KIDANI, Kenji INAGAKI, Toshiyuki SAOTOME, Hisashi KOIKE
    1973 Volume 22 Issue 7 Pages 896-899
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    Isonicotinylhydrazine (INAH) reacts with cupric ion to produce INAH-Cu(II) chelate (2: 1) at pH 4.5, which can be extracted with methyl isobutyl ketone (MIBK). Therefore, it is found that INAH can be quantitatively determined indirectly, if the quantity of Cu(II) in the organic phase is measured by atomic absorption spectrophotometry.
    Measurements are carried out with a Hitachi 207 atomic absorption spectrophotometer.
    The optimum working conditions for atomic absorption spectrophotometry are as follows: wavelength, 3247 Å; lamp current of hollow cathode lamp for Cu, 15 mA; slit width, 0.18 mm; air flow rate, 16.0l/min, and acetylene flow rate, 3.0 l/min.
    As a higher absorbance ratio was obtained in the range of pH 4.04.8, buffer solution at pH 4.5 was used in this measurement.
    Procedure for the determination was as follows; cupric chloride solution and aqueous INAH solution were mixed together with acetic acid-sodium acetate buffer solution which was adjusted to pH 4.5, and this solution was extracted with MIBK for 15 minutes twice, and it was kept standing for 10 minutes.
    The organic phase was centrifuged at 3000 rpm for 5 minutes, and the copper in organic phase was measured by atomic absorption spectrophotometer.
    The concentration of cupric chloride solution was 3 times more than that of INAH solution and the shaking time was at least for 10 minutes. The species extracted in MIBK layer showed the composition of INAH-Cu(II) to be 2: 1, which was determined by continuous variation method.
    The working curve for the MIBK extracts showed a good linearity over the range of 0.2×10-41.7×10-4 M INAH. The relative standard deviation of this method was calculated to be 0.44%, and the recovery of copper by the back-extraction with 1 N HCl was 98.5%.
    It was shown that this method might be applicable to the determination of INAH in the preparations, for no effect of the vehicles, such as soluble starch, gentiana powder, magnesium stearate and sodium benzoate, on the absorbance ratio was observed.
    Download PDF (534K)
  • Toshio ISHIZUKA, Hiroshi SUNAHARA
    1973 Volume 22 Issue 7 Pages 899-904
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    The atomic absorption behavior of europium and ytterbium was studied in an air-hydrogen flame as a cool flame. A Nippon Jarrell Ash AA-1E atomic absorption/flame emission spectrometer and HETCO total-consumption burner were used. Table I shows the experimental conditions.
    The effects of inorganic acids in the range of 0.012.5 M on the absorption of europium (300 ppm) and ytterbium (30 ppm) were investigated. Fig. 1 and Fig. 2 show the results. Hydrochloric acid in the range of 12.5 M slightly decreased the absorption of europium and increased that of ytterbium. Nitric acid decreased the absorption of europium by 30% and increased that of ytterbium by twice. Perchloric acid increased the absorption of europium and ytterbium, and the acid in the range of 0.010.1 M increased that of europium by 2.7 times and that of ytterbium by 4.5 times. Sulfuric acid and phosphoric acid remarkably suppressed the absorption of both the elements.
    The effects of metal ions in the range of 105000 ppm on the absorption of europium and ytterbium were investigated. Fig. 3 to Fig. 6 show the results. The absorption of europium increased in the presence of potassium of 101000 ppm, and that of ytterbium decreased with increasing the concentration of potassium. Magnesium and aluminum remarkably suppressed the absorption of both the elements, but the interferences with the absorption of europium were eliminated by adding 1% lanthanum. The absorption of europium gradually decreased with increasing the concentration of calcium, and that of ytterbium decreased by 80% in the presence of calcium of 1005000 ppm. The absorption of both the elements decreased with increasing the concentration of Cr, Mn, Fe, Pb, etc. The absorption of europium increased by 20% in the presence of La and Nd more than 100 ppm, and by 50% in the presence of Sm of 1000 ppm, but that decreased with increasing the concentration of Y and Dy. The absorption of ytterbium decreased with increasing the concentration of Y, La, Eu, Dy and Er.
    The calibration curve for europium was linear in the range of 0400 ppm. The calibration curve obtained by adding 0.1 M perchloric acid showed a sensitivity of 2.7 times in comparison with that for europium alone. The calibration curve for ytterbium obtained by adding 0.1 M perchloric acid showed a sensitivity of 4.5 times that for ytterbium alone and of 1.8 times that for ytterbium obtained in a nitrous oxide-acetylene flame.
    Europium in synthetic or practical samples as rare earth oxide was determined by atomic absorption method using the air-hydrogen flame. A sample was dissolved by perchloric acid, and europium in the sample solution was determined. Table II shows the results. In the determination of europium in the synthetic sample, the found value was in fair agreement with the theoretical value. In the determination of europium in practical samples, the values obtained were in fair agreement with the values obtained by flame emission method using a nitrous oxide-acetylene flame.
    Download PDF (853K)
  • Tomoo TAKAHARI, Michio NAKATA
    1973 Volume 22 Issue 7 Pages 904-908
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    A rapid and simple turbidimetric procedure of barium sulfate for the determination of sulfuric acid in waste acid solutions is described.
    The solution was composed of sulfuric and nitric acid, and contained hydrofluoric acid and several colored metal ions; the conventional procedure could not be employed because of co-precipitation of barium fluoride with barium sulfate and adsorptions of metal ions on the precipitate. It was found that the following procedure was very effective to take away the interruption of the above ions.
    (1) Saturated boric acid solution was added to the sample solution for the masking of hydrofluoric acid. Fluoride ion reacted with boric acid to form BF4- and did not co-precipitate with barium sulfate. When the concentration of hydrofluoric acid in the sample solution was higher than 3.5%, the masking with boric acid became less effective. However, since the hydrofluoric acid concentration in the waste acid solutions was lower than this, boric acid was found to be an effective masking agent for this purpose (See Fig. 8).
    (2) The wavelength at 560 nm was used in the offered method. This wavelength was obtained from the absorption curves in Figs. 1 and 2. At this wavelength, the blank absorption was minimized although it was not zero. A blank solution containing no barium chloride, was used to eliminate the interference with the colored metal ions.
    The recommended procedures are as follows.
    (1) 10 ml of the waste acid solution containing less than 7 mg of sulfate ions was taken into a 1000 ml measuring flask and diluted to the mark with distilled water. 5 ml of the diluted solution was taken in two beakers A and B, respectively.
    (2) 10 ml of saturated boric acid solution, 25 ml of water, 10 ml of a glycerine (1+1) solution, and 5 ml of 24% sodium chloride solution were added into the beakers A, and B.
    (3) 0.8 g of barium chloride was added to the beaker A by stirring with a magnetic stirrer.
    (4) The solution in the beakers A and B, were stirred for about 1 minute, lest standing for 4 minutes, and stirred again for 15 seconds.
    (5) The amount of sulfate ion was determined from the absorption at 560 nm against the blank solution in the beaker B that has not been added barium chloride.
    (6) The concentration of sulfuric acid (g/l) was calculated by the following equation;
    H2SO4(g/l)
    =SO42-(mg)×98.1/96.1×1000/5×1000/10
    The time required for the analysis was about 15 minutes for one sample and the results were accurate and reproducible as shown in Table I.
    Download PDF (623K)
  • Goro HIHARA, Miharu NAGATA
    1973 Volume 22 Issue 7 Pages 909-913
    Published: July 05, 1973
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    For the purpose of studying behaviours of trace components during rectification of liquids, a process to determine minor quantities of ethylene dichloride in benzene solution was developed, in which chlorine, linked to carbon in ethylene dichloride molecules, underwent a replacing reaction with potassium hydroxide in methanolic solution at elevated temperature, and resulting free chloride ion was extracted with water to be quantified by a titration procedure or a spectrophotometric method.
    1 ml of trial benzene solution, containing the weighed quantity of ethylene dichloride, was packed and sealed. in a glass ampoule together with 10 ml of 30% methanolic potassium hydroxide, and was heated at a constant temperature of boiling water for 2.5 hours, for the replacing reaction to be carried out completely. The reactants mixture was then extracted with chlorine free water and, after the separating of benzene phase, diluted precisely up to 100 ml, and the concentration of chloride ion in this aqueous solution was ascertained by one of different two ways. When the aqueous solution contained enough quantity of chloride ion for the titration measurement because of rich containment of ethylene dichloride in benzene, the determination was performed by a volumetric analysis according to Volhard's method:
    Remaining quantities of excess silver ion employed to precipitate chloride ion completely as silver chloride, was titrated with standard solution of ammonium thiocyanate using iron-alum as indicator under presence of nitrobenzene. In the case where the concentration of chlorine was not rich, determination was performed by spectrophotometric measurement of absorption with ferric thiocyanate complex which were formed by ferric ion and thiocyanate ion, equivalently produced from mercuric thiocyanate by replacement reaction of chloride ion.
    Above mentioned processes were operated for analysing ethylene dichloride of 0.6, 6 and 60 mg/ml of concentration in benzene, and recoveries of chloride ion vs. ethylene dichloride were estimated. The optimum conditions of the procedures were searched for the 100% recover, and they were; 30% of concentration of potassium hydroxide in methanolic solution as a replacing reagent, 10 : 1 of ratio of mixing volume of methanclic potassium hydroxide to volume of the benzene solution, and 2.5 hours of reaction time of replacement of chlorine.
    Average recoveries of ethylene dichloride and mean errors of them obtained as results of six times of analysis under optimum condition were 99.86± 0.12%, 99.95± 0.33% and 99.48± 0.33% for the concentrations of 60 mg/ml, 6 mg/ml and 0.6 mg/ml, respectively.
    Download PDF (610K)
  • Ryoji TOYODA, Terumichi NAKAGAWA, Toyozo UNO
    1973 Volume 22 Issue 7 Pages 914-915
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Reaction gas chromatographic technique was employed for the determioation of activation energy of the Shiff's base formation reaction. Benzaldehyde, cyclohexanone or 2-heptanone, which was injected into a gas chromatograph reacted with the amine present in a large excess in the reaction column which also contained the liquid partitioner i.e., QF-1, so that it was possible to treat the reaction as psuedo-first one. The rate constant of the reaction was determined graphically according to the following equation; ln(SI/SR) = kts ln(SI/SR0), where SI and SR are the peak areas of internal standard and the unreacted aldehyde or ketones, respectively and ts is the residence time of these reactants in the stationary phase which may be approximated to the corrected retention time.
    The rate constant (k) was obtained from a plot of ln(SI/SR) vs. ts and the activation energy was obtained from the slope of the Arrhenius plot of k's at various column temperatures.
    Download PDF (213K)
  • Kiyoshi TAKIURA, Akira YAMAJI, Kazuko IWASAKI, Hidetaka YUKI
    1973 Volume 22 Issue 7 Pages 916-918
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Components of Japanese incense sticks were analyzed by gas chromatography by use of a solid sampler. Analytical conditions were chosen so as to obtain the actual odor of burning incense sticks.
    Borneol, eugenol, α, β-santalol, coumarin, musk xylene and methyl p-coumaric acid ethyl ester were identified. These were considered to be natural and synthetic perfumes mixed in the incense sticks.
    Differences of components in commercial incense sticks (15 kinds) were distinctly shown by their gas chromatograms. Relations between odor of the burning incense sticks and their gas chromatograms were found.
    Download PDF (469K)
  • Katsumi YAMAMOTO, Fumiko SAKAI, Kousaburo OHASHI
    1973 Volume 22 Issue 7 Pages 918-921
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    8-Hydroxyquinoline reacts with Ti(IV) in the presence of excess hydrogen peroxide to form a ternary complex of yellow coloration. The ternary complex is extracted into chloroform and it shows a molar extinction coefficient, ε= 7, 300 at 425 nm at maximum absorption. This molar extinction coefficient is much larger than that of the complexes between Ti(IV) and 8-hydroxyquinoline or hydrogen peroxide. The composition of the ternary complex extracted is confirmed to be Ti(H2O2)(Oxine)2 by a solvent extraction method. Under the optimum conditions, Beer's law is obeyed for 9 to 40μg of Ti(IV) in 10 ml of chloroform.
    Download PDF (527K)
  • Morio TSUGE, Shigeyuki TANAKA
    1973 Volume 22 Issue 7 Pages 921-924
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    The determination of isomers of mononuclear methylol phenols in phenol-formaldehyde resole resins was studied by two-dimensional thin-layer chromatographic separation and ultraviolet spectroscopy with phlorogrucin dihydrate as an internal standard.
    The optimum thickness of cellulose plates used were 0.6 mm. The first developing solvent was water and the second one was a mixture of benzene-acetic acidwater (5 : 5 : 1). The sum of the first and second developing time in thin-layer chromatography was about one fifth as long as that in paper chromatography for the qualitative analysis.
    The extracts of each spots with methyl alcohol were determined by the key band at 269 nm for phlorogrucin dihydrate, and at about 280 nm for mononuclear isomers.
    The reproducibility of the determination of 2-methylol phenol was about 10 per cent by the coefficient of variance. However, 4-methylol phenol, 2, 4-and 2, 6-dimethylol phenols and 2, 4, 6-trimethylol phenol were determined semi-quantitatively; the correction coefficients used were obtained by using standards in which cresols, ethyl phenols, dimethyl phenols, trimethyl phenol, dimethylol cresols, and monomethylol xylenol were substituted to these materials except 2-, and 4-methylol phenols, respectively.
    Download PDF (619K)
  • Masanori AKIBA, Kyoji TÔEI, Yasuaki SHIMOISHI
    1973 Volume 22 Issue 7 Pages 924-926
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    ο-Phenylenediamine reacts with nitrite to form 1H-benzotriazole which can be extracted into MIBK.By means of injection of this MIBK layer into gas-chromatograph equipped with a thermal conductivity detector, the nitrite is determined from the peak height. Though the sensitivity is low compared with the colorimetric method, the gas-chromatographic method is superior in the specificity.
    Put 20 ml of the sample solution and 3 ml of 1 N hydrochloric acid into a 100-ml separatory funnel, and then, add 2 ml of 0.0187 M ο-phenylenediamine solution. After standing for 20 min, 5 ml of 1 M sodium acetate is added and 11 g of sodium chloride is added. Then, the 1H-benzotriazole formed is extracted into 1 ml of MIBK by shaking for 10 min andthe MIBK extract is dried with 0.5 g of molecular sieves 3 A. Five micro liters of the MIBK extract isinjected into the gas-chromatograph and the peak height is measured. The nitrite content is calculated by using a calibration curve which has been drawnpreviously by experiments with known amounts of nitrite.
    Download PDF (451K)
  • Study on automatic chemical analysis of steel. I
    Akihiro ONO, Isamu TAGUCHI, Ryutaro MATSUMOTO
    1973 Volume 22 Issue 7 Pages 927-929
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    An automatic apparatus has been developed for measuring the absorbancies of colored sample solutions in measuring flasks. The apparatus consists of a sample solution changer with twelve suction tubes, aspectrophotometer with flow-through cuvette and an aspirator. The changer is mainly made up of twelve electromagnetic cocks, each of which is fitted with one of the twelve tubes dipped in the colored sample solutions. It is automatically controlled to open the cocks in order, sucking the sample solutions through the flow-through cuvette for absorbancy measurement. The cock is newly applied and works on the basis of pressing a tube between the plunger and the metal rod for closing the flow-pass of the tube.
    The time required for measuring absorbancies of twelve sample solutions was about 6 min. The analytical results showed a good accuracy and reproducibility.
    Download PDF (476K)
  • Hiroyuki YOSHIDA, Chushiro YONEZAWA
    1973 Volume 22 Issue 7 Pages 929-931
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    A method is described for the determination of traces of sodium in high-purity zinc and selenium by neutron activation. The sample and portions of standard solution were irradiated in JRR-2 for 20 min at a thermal neutron flux of about 7 × 1013n/cm2· sec.The samples irradiated were cooled for about 2 hours.The zinc sample was etched with 5 N sulfuric acid and then dissolved in concentrated hydrochloric acid. The selenium sample was etched with aqua regia, dissolved in concentrated nitric acid, and converted to concentrated hydrochloric acid solution. The sample solution was poured into a hydrated antimony pentoxide (HAP) column (5φ × 30 mm) which was previously conditioned with concentrated hydrochloric acid. The column was washed with concentrated hydrochloric acid. Sodium-24 was adsorbed on HAP but zinc and selenium were not. The column was transferred to a polyethylene vial and its γ-activity was measured with a 3 x 3 inch NaI(Tl) detector and 400 channel pulse-height analyzer. The 2.754 MeV γ-ray photopeak of 24Na was used for the determination. The standard solutions were treated in the same way as the samples. Nuclides produced from zinc and selenium did not interfere with the determination of sodium.
    The proposed method was successfully applied to three NBS standard samples. A detection limit of this method was 10-3 ppm Na in zinc and selenium.
    Download PDF (432K)
  • Tadaoki OKUMOTO, Tsugio TAKEUCHI
    1973 Volume 22 Issue 7 Pages 931-933
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    The hydrogenation mechanisms and the structures of hydrogenated polyvinylchloride (HPVC) were studied by pyrolysis-gas chromatography.
    Hydrogenated polyvinylchloride were formed with lithium aluminum hydride in boiling tetrahydrofuransolution. Raw polyvinylchloride (PVC) yielded aromatic hydrocarbons such as benzene, toluene and styrene at the pyrolysis temperature of 590°C. These characteristic products were formed by dehydrochlorination reaction followed by cyclization from the triadof vinylchloride units on decomposition.
    The yields of aromatic products from HPVC weredecreased monotoilously with the rise of degree of hydrogenation (DH). It was suggested that the triad of vinylchloride unit in HPVC were decreased with the rise of DH. By comparison with the yield ofaromatic hydrocarbon from HPVC and random andb lock copolymers, it was considered that random hydrogenation of HPVC partially contains the block structures.
    Download PDF (382K)
  • [in Japanese]
    1973 Volume 22 Issue 7 Pages 934-942
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (1477K)
  • [in Japanese]
    1973 Volume 22 Issue 7 Pages 943-948
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (781K)
  • [in Japanese]
    1973 Volume 22 Issue 7 Pages 948-956
    Published: July 05, 1973
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (1732K)
feedback
Top