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Volume 28, Issue 12
Displaying 1-17 of 17 articles from this issue
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Yukio MINAMI, Toshiyuki MITSUI, Yoshikazu FUJIMURA1979 Volume 28 Issue 12 Pages 717-720
Published: December 05, 1979
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSBiacetyl reacts with hydroxylamine hydrochloridesodium acetate solution and nickel ion, and water insoluble complex which is N-dimethylglyoxime is formed. Biacetyl could be, therefore, determined directly by measuring the amount of nickel in precipitate by atomic absorption spectrophotometry (A. A. S.). The recommended procedures is as follows: The sample solution {containing (0.052.00)mg of biacetyl} is mixed with 3 ml of hydroxylamine hydrochloride-sodium acetate solution (80.68 mg of NH2OH·HCl per ml, 40.21 mg of CH3COONa per ml). The mixture is heated on waterbath at 75°C for 10 min. After cooling, the mixture is added 2 ml of nickel solution (6.30 mg of Ni2+ per ml), and then to stand for 5 min. After filtrating, the precipitate is washed with water, and dissolved by adding 2 ml of conc. nitric acid, followed by diluting to 100 ml with water. The nickel content of the resultant is measured by A. A. S. No detectable interference for determination of biacetyl occured with any other compounds, such as acetone, ethyl acetate, ethanol, acetic acid, acetaldehyde, phenol, aniline, lactic acid, glucose, Cu2+, Fe3+, Mg2+ and K+.View full abstractDownload PDF (584K) -
Yasuhiko YOTSUI, Hisashi NOMURA, Mitsuji SANO, Yoshihiro KUDO, Shinich ...1979 Volume 28 Issue 12 Pages 721-727
Published: December 05, 1979
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe system of CHEMICS was applied to the determination of the amino acid sequence of polypeptides. The composition of amino acids in the sample was determined by amino acid analysis and its constitution was determined as follows: After partial hydrolysis of the sample with 6 N HCl (80°C, 4 h), the mixture was esterified with CH3OH-HCl followed by acetylation with the mixture (1:1) of (CH3CO)2O and (CD3CO)2O at room temperature overnight. The reaction mixture was introduced into mass spectrometer equipped with c. i. source without any separation procedures. Each peptide fragment was detected as a characteristic doublet cluster ion peak. The probable structures (candidates) of polypeptide were constructed from the peptide fragments as executed in CHEMICS. The c. i. spectra of the hydrolysis mixture of neuroteosin suggested the presence of 14 oligopeptides, and eight candidates were derived. In the present method, Leu could not be distinguished from Ile. Therefore the number of all the possible candidates was 24. In the case of eledoisin related peptide, two candidates were derived from six fragments. In the case of buradykinin potentiator C the number of all the possible candidates was 40.View full abstractDownload PDF (1262K) -
Hiroko KANEKO, Keiji KANEKO1979 Volume 28 Issue 12 Pages 727-733
Published: December 05, 1979
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe current observed during the polarographic reduction of titanium(IV) in the solution containing ethylenediamine tetraacetic acid (EDTA) and acetate is considerably increased in the presence of bromate ion. The current caused in the solution is called a polarographic catalytic current and measured by d.c. polarograph. A new method for a microdetermination of titanium was proposed by using the catalytic current. The catalytic current (icat.) given in 5×10-6 M TiEDTA chelate-0.001 M KBrO3-0.2 M CH3COONa system was 0.66 μA and the half wave potential was -0.35Vvs.SCE at pH 4.0. In the presence of a larger amount of bromate ion in comparison with a amount of titanium chelate ion, catalytic currents were proportional to the concentration of titanium(IV) in the range of (5×10-72×10-5) M. The determination and the detection limits were 0.024 μg/ml and 0.005μg/ml, respectively. The coefficient of variation in the determination of titanium was 2.3 %. The presence of gelatin tended to decrease the catalytic current. The determination was interfered by the coexistence of iodate, tellurite or hydrogen peroxide of 20 times amount of titanium. Each presence of Cu(II), Mn(II), In(III), Fe(III), I-, S2O82-, SeO32-, CrO42- or MoO42- of 20 times amount of titanium slightly interfered with the determination. The method was applied to the analysis of titanium in thin films of titanium carbide containing (0.625) μg of titanium. The analytical results of two thin films evaporated simultaneously, were compatible well each other. The polarographic catalytic current is useful for the determination of microamounts of titanium, because of high sensitivity, selectivity, good reproducibility and inexpensive instrument.View full abstractDownload PDF (1285K) -
Yoshio YOSHIDA, Kanji I1979 Volume 28 Issue 12 Pages 733-737
Published: December 05, 1979
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA simple rapid fusion technique, in which the lithium metaborate-sodium peroxide mixture is used as the fusing agent, has been developed for the analysis of refractory substances such as sands, bricks and oxide inclusions in steel. A platinum crucible is used as a container for fusion of the sample. The melt is dissolved in dilute acid solution, and the metallic elements: aluminum, silicon, calcium, titanium, chromium, manganese, iron, zirconium, niobium etc., are determined by spectrophotometry or atomic absorption spectrophotometry. The experiments were made to analyze the various oxides, carbides, nitrides and compound oxides, and the satisfactory results were obtained. The principal advantages of the proposed fusing agent are as follows: (1) Even substances that can not be fused with the others, are fusible. (2) A platinum crucible does not be injured. (3) The melt can be dissolved without the trouble such as the precipitation occurence.View full abstractDownload PDF (957K) -
Shoji HIRAI, Yoshiko ARIKAWA, Takejiro OZAWA1979 Volume 28 Issue 12 Pages 738-743
Published: December 05, 1979
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA rapid and precise method for the determination of selenium and tellurium was developed by means of an instrumental neutron activation analysis. The method was successfully applied to the analysis for trace quantities of selenium and tellurium contained in natural sulfur deposits around craters or fumaroles. The 79mSe and 131Te nuclides were used for a simultaneous determination of selenium and tellurium. When a very high sensitivity was required, a short-lived 77mSe was measured because its production rate was about 50 times higher than that of 79mSe. Powdered samples of sulfur were irradiated in Musashi Institute of Technology Reactor at a thermal neutron flux of 1×1012 n cm-2 s-1 either for 5 min with 200 s detection for the simultaneous determination of selenium and tellurium or for 10 s with 30 s detection for the trace determination of selenium, with a Ge(Li) detector coupled to a multichannel analyzer. Spectrum data were analysed with a mini-computer. All measurements were practically free from interference due to 32P induced in sulfur with the methods. Reproducibility of the results was found within 10 % when the synthetic mixtures of elemental sulfur with selenium and tellurium were analysed by the present methods. The agreement between the results obtained with both 79mSe and 77mSe was satisfactory. Selenium and tellurium in the natural elemental sulfur was precisely and rapidly analysed by the present method.View full abstractDownload PDF (936K) -
Masahiro SON, Hitoshi HAYASHIDA, Masataka NISHIYAMA1979 Volume 28 Issue 12 Pages 743-748
Published: December 05, 1979
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA Staircase convolution polarograph was constructed. In this polarograph, the staircase voltammetry current, i, is converted to a new function, Ic, which represents the change of the surface concentration of depolarizer, by Ichise's s-1/2 module according to eq. (1)
Ic=∫t0i(η)/√π(t-η)dη……(1)
Theoretical expression of the current vs. potential curves in staircase voltammetry and staircase convolution voltammetry with the step voltage of ΔE and the step interval of τ are discribed as nondimensional functions (2) and (3),
ψs(j, Δζ)=i√τ/nFA*C√D……(2)
φs(j, Δζ)=Ic/nFA*C√D……(3)
for an n-electron reversible reduction step, where Δζ=nFΔE/RT, t=jτ with j=1, 2, 3, …, A=electrode surface area and other symbols have usual meanings. Experimental results generally agreed with theoretical predictions (for 10 ppm Cd2+ in 0.1 M KCl with Hanging mercury drop electrode). By staircase convolution voltammetry the charging current was effectively eliminated and linear correlations between Ic and concentration were obtaind for Cd2+ and Pb2+ in the concentration range from 10-7 to 10-4 M.View full abstractDownload PDF (933K) -
Ichiro HAYASHIDA, Hitoshi YOSHIDA, Mitsuhiko TAGA, Seiichiro HIKIME1979 Volume 28 Issue 12 Pages 748-753
Published: December 05, 1979
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA conductometric determination of Hg(II), Ag(I) and Cd(II) was carried out by using the insoluble ternary complex formation of the metal ions with iodide ion in the presence of 1, 10-phenanthroline(phen). Recommended procedure is as follows; An aliquot of sample solution containing (1429) mg of Hg(II), (816) mg of Ag(I), and (917)mg of Cd(II) transfered into a 100 ml beaker. Add to acetate buffer and stoichiometric amounts of phen (40 % ethanol-water solution). Amounts of nitrate ion which was estimated separately by other titration with 0.1 M Ag(phen)2 complex (40 % ethanol-water solution) are adjusted in the range of (4.06.0)mM. The sample solution is titrated with 0.1 M KI standard solution at the rate of 0.20 ml/min or less. The titration curve showed three end-points corresponding to the formation of (1) Hg(phen)2I2, (2) Ag(phen) I, and (3) Cd(phen)2I2. The relative standard deviation was less than 0.8 %, when the pH value was controlled at 4.04.5 (acetate buffer) and the nitrate concentration was adjusted in the range of (4.06.0)mM. The effect of diverse ions on the determination was also investigated in detail.View full abstractDownload PDF (1065K) -
Chikao TSURUMI, Keiichi FURUYA, Hitoshi KAMADA1979 Volume 28 Issue 12 Pages 754-759
Published: December 05, 1979
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe method of the spectrophotometric determination of thorium with 2-(2-thiazolylazo)-5-dimethylaminophenol (TAM) in the presence of cetylpyridinium chloride (CPC) and methanol was investigated. Thorium reacts with TAM in the presence of CPC and methanol to form reddish-violet ternary complex. The maximum absorbance at 570 nm is constant in the pH range from 4.3 to 4.8 and stable for at least 90 min. Beer's law is obeyed up to 2.4μg cm-3 of thorium. The molar extinction coefficient of this wavelength is 8.5×104 dm3 mol-1 cm-1 and the absorption sensitivity for thorium was 2.7×10-3μg cm-2 per 0.001 of absorbance. The molar ratio of thorium to TAM in the complex was confirmed to be 1:3 by both the continuous variation and mole ratio methods. The conditional formation constant of the ternary complex is 2.89×1018. Ba(II), Be(II), Ce(III), La(III) and Sr(II) can be masked by the addition of 2.0 cm3 of 1×10-2 mol dm-3 thiosemicarbazide solution as a masking agent. Co(II), Fe(III), Ni(II), V(V) and Zr(IV) seriously interfere with the determination of Th(IV) and show positive errors, while Fe(II), Mo(VI), Ta(V) and W(VI) interfere with it and do negative errors.View full abstractDownload PDF (740K) -
Yoshinobu AKADA, Sadako KAWANO, Yaichiro TANASE1979 Volume 28 Issue 12 Pages 760-762
Published: December 05, 1979
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA rapid and sensitive method using high-speed liquid chromatography was devised for the determination of arbutin and hydroquinone in human urine and rat plasma. The procedure involves Amberlite XAD-2 column chromatographic separation from human urine sample and methanol extraction from rat plasma sample, respectively. The water effluent or methanol extract is injected into the chromatograph, with a Zorbax CN column (4.6 mm i. d.×25 cm), water as mobile phase, a flow rate of 1.0 ml/ min, and a column temperature of room temperature. Arbutin and hydroquinone are detected by their absorbance at 221nm and quantitated by measuring peak heights. Separation of both compounds is achieved within 10 min. The limits of detection were 2 μg/ml of human urine and 1μg/ml of rat plasma, respectively. The recovery of both compounds from urine and plasma was (98101)%, and the coefficient of variation (0.800.92)%, respectively.View full abstractDownload PDF (506K) -
Tomoo MIWA, Atsushi MIZUIKE1979 Volume 28 Issue 12 Pages 762-765
Published: December 05, 1979
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe purification of water was carried out through ion exchange, distillation, adsorption, filtration, and sub-boiling distillation from a vitreous-silica still. The water purity was checked by differential pulse anodic stripping voltammetry. Appreciable amounts of zinc {(0.20.4) ppb} were found in the distillate, originating from dust particles in the atmosphere of a conventional chemical laboratory. To avoid airborne contamination, the distillate outlet and a Teflon collecting bottle were tightly enclosed in a polymethyl methacrylate chamber, 20 cm×20 cm×25 cm, which was flushed with argon filtered through a 0.025-μm membrane filter. The resulting water contained 0.02 ppb of zinc, 0.01 ppb of lead, less than 0.01 ppb of cadmium, and less than 0.1 ppb of copper, which equaled in purity the water obtained by sub-boiling distillation in a class 100 vertical-laminar-flow clean hood.View full abstractDownload PDF (601K) -
1979 Volume 28 Issue 12 Pages T73
Published: 1979
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSDownload PDF (82K) -
Studies on analytical methods by amperometric titration using a rotating platinum electrode. XXXVIISanae IKEDA, Hiromu SATAKE, Takeshi KOYAMA1979 Volume 28 Issue 12 Pages T51-T53
Published: December 05, 1979
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSMetallic selenium was dissolved in concentrated nitric acid, and the resulting selenite ion was titrated with silver nitrate solution in an alkaline solution by short-circuit amperometric method using a rotating platinum wire electrode (1200 rpm) vs. SCE. The recommended procedure is as follows. Dissolve powdered selenium {(440) mg} with concentrated nitric acid {(0.30.5)ml} in a 20 ml weighing bottle at 110°C using a glycerin bath (5 min), continue heating until a syrup remains (10 min). Dilute the syrup with water to make 100 ml of the sample solution. Titrate an aliquot of the solution with 0.1 M silver nitrate solution amperometrically after adjusting the pH to 10 with sodium hydroxide solution. Metallic selenium was determined by the proposed method with the relative error and the coefficient of variation of 0.1 % at its weight from ca. 4mg to ca. 40 mg.View full abstractDownload PDF (442K) -
Sanae IKEDA, Hiromu SATAKE1979 Volume 28 Issue 12 Pages T53-T56
Published: December 05, 1979
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSAn iodometric method for the rapid determination of dithiocarbamate salts was studied by potentiometric titration using a platinum indicator electrode and a saturated calomel reference electrode. It was found that dithiocarbamate salts could be titrated with iodine-potassium iodide standard solution in the presence of Triton X-100 at the temperature of (1015) °C and the pH of 7.5. Sodium dimethyldithiocarbamate {(0.0020.008) M}, dimethyldithiocarbamate dimethylammonium {(0.0010.01) M}, sodium diethyldithiocarbamate {(0.0010.004) M}, diethyldithiocarbamate diethylammonium {(0.0020.01) M}, potassium dibenzyldithiocarbamate {(0.0010.002) M} and ammonium pyrolidine-N-dithiocarbamate {(0.0020.008) M} were determined within less than 0.3 % of relative deviation and of coefficient of variation. The recommended procedure is as follows. Place 10 ml of 0.01 M dithiocarbamate salts into the titration cell. Add 5 ml of 5 % Triton X-100 and 4 ml of disodium phosphate-citric acid buffer solution (pH=7.5). Dilute with water to 50 ml. Titrate the resultant solution with 0.025 N iodine-potassium iodide standard solution potentiometrically. The whole procedure requires less than 10 min.View full abstractDownload PDF (672K) -
Haruo HONMA, Keiko SUZUKI, Mutsuko YOSHIDA, Hisako YANASHIMA1979 Volume 28 Issue 12 Pages T56-T60
Published: December 05, 1979
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA method for the determination of micro gram level of cyanide was developed by using gas chromatography. Cyanide (or thiocyanate) ion was treated with bromine to form cyanogen bromide, which was then detected by an electron capture detector. One ml of a sample containing cyanide (or thiocyanate) ion was taken in a 10 ml reaction tube with ground-glass joint and mixed with 0.5 ml of 20 % phosphoric acid and one drop of bromine water. After shaking and standing for 10 min, 0.2 ml of 5 % phenol solution was added to eliminate bromine remaining. Then the formed cyanogen bromide was extracted with 5 ml of ethyl ether. After 15 min, (0.51.0) μl of the ether layer was measured by ECD gas chromatography. The gas chromatographic conditions are as follows; column packing, Porapak QS (80/100 mesh); column size, 1 m×3 mm i. d.; column temp., 130 °C; injection temp., 130°C; carrier gas, N2 30 ml/ min; diluent gas, N2 20 ml/ min; detector volt, 8 V DC. Chloride, iodide, nitrate, and many metal ions such as Fe(III), Co(II), Ni(II), and Cu(II) did not interfere but fluoride and sulfate yielded lower and higher results, respectively. By this method minimal detectable quantity was about 0.5 ppb. The method was applied to determine cyanide in practical samples.View full abstractDownload PDF (752K) -
Yoshinobu NAGAWA, Kitoshi UEMATSU, Shuzo TOKUNAGA1979 Volume 28 Issue 12 Pages T61-T65
Published: December 05, 1979
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSIn order to study the discrepancy between the oil content in waste water measured with nondispersive infrared analyzer (NDIR) and infrared spectrophotometer (IRSP), the carbon tetrachloride solution of various mineral oils, vegetable oils, and animal oils under the same concentration were measured with them. If B heavy oil was used as a standard material, the deviation of the oil content were about ±20 % both with NDIR and IRSP. The coefficients of variation of the oil content obtained with NDIR and IRSP were 10.7 % and 8.5 %, respectively (Table 2). The correlation coefficient between the oil content obtained with NDIR and the absorbance at 2925 cm-1 obtained with IRSP, the oil content obtained with NDIR and the mean absorbance of three bands (at 2960 cm-1, at 2925cm-1, and at 2850cm-1) obtained with IRSP, and the oil content obtained with NDIR and the area of spectrum at the region from 2800 to 3000 cm-1 obtained with IRSP were 0.21, 0.75, and 0.94 (Fig. 2, 3, and 4), respectively. It is necessary to take it into account that there is some difference between the data obtained with NDIR and IRSP for the oil content in waste water. B heavy oil, cetane, and standard mixture (a mixture of 37.5 % isooctane, 37.5 % cetane, and 25 % benzene) used as standard materials for the determination of the oil by infrared absorption method showed fairly different data when measured with both NDIR and IRSP (Table 1). It must be noticed that the oil content in waste water are different according to the choice of the standard materials.View full abstractDownload PDF (895K) -
Hajime ITO, Yoshihiko KANCHIKU, Tomihiko KAWAMURA, Masao YOSHIDA1979 Volume 28 Issue 12 Pages T65-T67
Published: December 05, 1979
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA new technique of powdering acrylic fiber was studied for X-ray spectrometry. In the technique developed here, fiber was cut and milled by shaking with quartz fragments. It was applied to the determination of tin in acrylic fiber in the range of (0.10.5) weight percent. The ability of powdering and reproducibility of the measured X-ray intensity depended on the weight ratio of fiber to quartz and mixing time. The best results were obtained when mixing 2.00 g of fiber with 4.50 g of quartz for 60 min. The powder was pressed under the load of 10 ton/cm2. Tin was determined by the dissolution technique at the same time and the deviation of the two different determinations was (0.010.06)%. This technique is applicable to analyze the other elements in fibers by X-ray spectrometry.View full abstractDownload PDF (475K) -
Seiichiro HIGUCHI, Hisao SATO, Shigeyuki TANAKA1979 Volume 28 Issue 12 Pages T68-T72
Published: December 05, 1979
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe direct quantitative analysis of solid samples by laser Raman spectrometry was examined methodologically. It was shown that the usual methods of sample handling for solid samples (for example, holding samples in a glass capillary, or forming samples into pressed pellets) do not give satisfactory results for the purpose of quantitative determination of mixed samples because of the inevitable inhomogeneity. In thepresent investigation, we proposed and examined the two methods of avoiding or minimizing this influence of sample inhomogeneity. One of them is to average the inhomogeneity of samples by rotating rapidly sample pellets which results in the increase of the parts of samples contributing to the spectral intensities. The other is to melt solid samples by heating into homogeneous liquid states. Using some model compounds, these methods were examined in view of direct quantitative determination of solid samples. It was clarified that both of the methods give the reproducible intensity values and the linear relations between intensities and concentrations with the precisions good enough. Thus, the present experimental results can be concluded to indicate the possible approaches to the quantitative treatments of practical samples which are insoluble in solvents suitable for Raman spectrometry such as water.View full abstractDownload PDF (880K)
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