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Volume 17, Issue 9
Displaying 1-29 of 29 articles from this issue
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Tsuneo SHIRAI, Masashi MIURA, Hiroyuki KODERA, Saburo YANAGISAWA1968 Volume 17 Issue 9 Pages 1051-1055
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA diaphragm manometer which requires no calibration of indicated values by the sort of gases and is ready for continuous recording has been presented for use in gas analyses.
This diaphragm manometer has been designed as to have a response to 6×10-48×10-2 mmHg. The detector is a capacitance transducer, in which a stainless steel diaphragm of 0.01 mm thickness and a quartz plate spattered with gold at a distance of 100 μ consist a parallel plate condensor. In this detector, the reference and the unknown are separated by the diaphragm, and a change of the pressure in the unknown is converted to a change of the capacitance between the diaphragm and the counter electrode, which is detected by the capacitance bridge using alternating current of 30 kc/sec. This signal is lead to the servosystem, in which it is amplified to give an input voltage to bring back the diaphragm to its null position by an induced electrostatic attraction. The direct current voltage is recorded as the response of gas pressure. It was successfully used for micro-analysis of trace gases in metals.View full abstractDownload PDF (652K) -
Koichi KATOH1968 Volume 17 Issue 9 Pages 1055-1060
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSColor changing ranges of some pH indicators in water-dioxane system were compared through their absorption spectra. Mode of color changing with varying dioxane concentration was quite similar to that in water-alcohol mixtures8). Thymol Blue gave by itself a red color in 90% dioxane solution, its absorption spectrum indicating that Thymol Blue was in its acid form.
This seemed rather strange, although Cresol Red also showed its acidic color in 90% dioxane. Thymol Blue did not show its acidic color in water-methanol, water-ethanol, and water-acetone mixtures.View full abstractDownload PDF (767K) -
Ryozo NAKASHIMA, Shozo SASAKI, Masamichi FURUKAWA1968 Volume 17 Issue 9 Pages 1061-1065
Published: September 05, 1968
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe differential polarographic titration of copper by EDTA was studied. Two platinum electrodes of 0.5 mm in diameter and 3 mm in length were used after being anodized in 1 M H2SO4.
The titration curves in acidic media such as trichloroacetate, monochloroacetate and acetate buffer solutions did not show typical peaks, and the extrapolated end points were lower than the theoreticals. The experiments in ammonical buffers showed that the titration curves in NH3-NH4Cl was more statisfactory than those in NH3-NH4NO3 or in NH3-(NH4)2SO4. The optimum conditions were: pH 7.510.2 NH3-NH4Cl 0.4 M and the current 1.24.8 μamp.
Zinc and calcium were back-titrated with a standard solution of copper after the addition of excess EDTA in 0.4M NH3-NH4Cl solution (pH 9.0), provided the dissolved oxygen in the sample solution had been previously removed. When glassy carbon indicator electrodes were used for the back-titration, this removal of dissolved oxygen was not necessary.View full abstractDownload PDF (667K) -
Ryozo NAKASHIMA, Masamichi URUKAWA, Shozo SASAKI, Shozo SHIBATA1968 Volume 17 Issue 9 Pages 1066-1071
Published: September 05, 1968
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe differential polarographic titration of cerium with hydroquinone standard solution was studied, and the method was applied to the determination of cerium in yttrium oxide.
The strengths of 0.01 N and 0.001 N hydroquinone-solutions containing 0.005 M H2SO4 were unchanged at least for 30 days. The conditions for obtaining the most favorable titration curves using a pair of glassy carbon electrodes (area 0.07cm2) were : constant current 0.51.0 μA, and titration speed near the end point 0.2 ml/min. Under these conditions, 10 mg 20 μg of cerium was determined in a wide range of concentration of H2SO4 or HNO3 with good reproducibility.
One tenth amount of parmanganate did not interfere, but beyond this value, the titrant consumed was decreased. In the presence of chromate or vanadate, two inflection points were obtained on the titration curves. Simultaneous determination of cerium and chromate or vanadate by these curves gave insufficient results. Less than 1/10 amount of chromate or 1/2 amount of vanadate was only permissible for precise determination of cerium. Tungsten(VI), Mo(VI), Fe(III), Ti(IV), Th(IV) and Pb(II) by the same amount did not interfere.
Several methods for oxidation were compared on the influence of oxidizing agents, among which the oxidation with PbO2 in 23M HNO3 was most suitable.View full abstractDownload PDF (943K) -
Naobumi OI, Hiroshi TAKEDA1968 Volume 17 Issue 9 Pages 1071-1075
Published: September 05, 1968
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe infrared absorption spectra of aromatic molecular complexes were investigated in Nujol mulls and some regularities were found in 1000700 cm-1 region.
(1) In π type molecular complexes, although the spectra appear to be a summation of the spectra of the two components, the CH out-of-plane bending vibration bands of electron donors are sensitive to complex formation and always shifted to higher frequencies.
(2) The infrared absorption spectra of molecular complexes of picric acid are essentially classified into two groups, i.e., those of π type bondings and those of salt bondings. The bond types of the complexes can be readily distinguished by their characteristic absorption bands in the 1000700 cm-1 region as well as by the well known absorption bands in 40002000 cm-1 region.View full abstractDownload PDF (724K) -
Nobuhiko IRITANI, Taketsune MIYAHARA, Ichiro TAKAHASHI1968 Volume 17 Issue 9 Pages 1075-1080
Published: September 05, 1968
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA fluorophotometric titration method for determination of Cr(III) involving back-titration of an excess of EDTA with metal salt solution was established. By using copper sulfate as a titrant, Calcein or Calcein Blue was effective as an indicator. By use of Calcein Blue indicator, the titration curve showed a distinct inflection, and the end point was obtained as the intersection of two straight lines. Calcein, on the other hand, did not give a distinct inflection point on the titration curve, but the end point was readily obtained by the aid of a straight line represented by an equation derived from the chelating equilibrium formula. From 0.5 to 5 mg of Cr(III) could be determined with an error less than 1%.View full abstractDownload PDF (687K) -
Teizo IGUCHI, Takashi TAKIUCHI1968 Volume 17 Issue 9 Pages 1080-1087
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSAcetylated polyesters as stationary phase liquids were examined for the analysis of formaldehyde, methyl alcohol and water by gas chromatography. Glycols, such as ethylene glycol and diethylene glycol, and dibasic acids, such as succinic, adipic and phthalic acids were used for preparing the polyesters. The terminal hydroxy groups of these polyesters were acetylated with an acetic anhydride-pyridine mixture. The behaviors of formaldehyde and water to the non-acetylated and acetylated polyesters as stationary phases were compared with those to the triacetin. The resulotion of peaks of acetylated polyesters was superior to that of the non-acetylated. Acetylated polyethylene glycol adipate was profitable particularly for the analyses of aldehyde-alcohol-ketone-water mixture containing formaldehyde and of heating products of formaldehyde resins. Acetylated polyethers, such as polyethylene glycol 4000, 20 M, and polypropylene glycol 2000, were also effective. Acetylated polyesters and polyethers were thermally more stable than triacetin.View full abstractDownload PDF (891K) -
Itiro TOYAMA, Tomizo NAKAMURA, Akihiko KATO, Kiyoshi SATO1968 Volume 17 Issue 9 Pages 1087-1091
Published: September 05, 1968
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA preparation of high purity hydrofluoric acid for semiconductor was studied, on (1) a method of fractional distillation of a highly concentrated hydrofluoric acid by a new rectifying column made of fluorine resin, and (2) fates of phosphate and arsenic in the course of purification and analysis which were followed by the use of 32P and 74As.
As the result, high purity hydrofluoric acid (concentration 51%; fluosilicic acid 0.0004%; phosphate 0.000005%; arsenic 0.000001%) was obtained with 80% yield by a distillation of 1 kg of raw 68% hydrofluoric acid (fluosilicic acid 0.2%; phosphate 0.003%; arsenic 0.002%; sulfate 0.01%) at 2425°C for 24 hours with 50 g of (NH4)2S2O8, 20 g of Ag2SO4 and 50 g of Na2CO3.
Repeated distillations gave an acid almost free from phosphate and arsenic.View full abstractDownload PDF (743K) -
Yasuharu NISHIKAWA, Keizo HIRAKI, Kiyotoshi MORISHIGE, Akira TSUCHIYAM ...1968 Volume 17 Issue 9 Pages 1092-1097
Published: September 05, 1968
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe fluorometric method for the determination of aluminum [This Journal, 16, 692 (1967)] was adopted for analysis of aluminum in sea water.
Sample water containing 0.0032 μg of aluminum was treated with 0.5 ml of 0.01% lumogallion solution, and pH was adjusted to 5.0 (CH3COONH4-CH3COOH buffer). It was heated at 80°C for 20 minutes, and the intensity of fluorescence of the solution was measured. Ferric iron interfered with this procedure, and hence the aluminum content in sample water was determined by using a calibration curve obtained in the presence of equivalent amounts of ferric iron.
The amounts of dissolved aluminum and the perticle size distribution of aluminum in suspension were determined successfully by the above procedure. The freezing storage of sea water gave good results.View full abstractDownload PDF (735K) -
Yoshimi SASAKI1968 Volume 17 Issue 9 Pages 1097-1102
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA simple and rapid method for the determination of iron in various samples has been developed. A sample is dissolved in hydrochloric acid and oxidized to iron(III) by hydrogen peroxide. The solution is boiled to remove hydrogen peroxide, and made to about 7N in hydrochloric acid concentration. After cooling, iron(III) is extracted with methyl isobutyl ketone (MIBK): The MIBK phase is washed with 7N hydrochloric acid, and a definite volume of an acetate buffer solution and a few drops of tiron indicator are added. The solution involving MIBK is directly titrated with a cupferron standard solution, whereby MIBK plays another role as an extractant of iron(III) cupferrate and there is no need to reject the organic solvent through a procedure. Copper and aluminum do not interfere, and 0.5 mg or more of iron can be determined satisfactorily. The time required for a run is about 20 minutes.
Good results were obtained in the determination of iron in technical hydrochloric acid, technical sulfuric acid, aluminum metal, aluminum alloys, copper powder, technical copper sulfate, aluminum bronze, nickel alloys, zinc metal, magnesium metal, limestone, marble and portland cement.View full abstractDownload PDF (870K) -
Nobu KIKUCHI, Taihei MIKI1968 Volume 17 Issue 9 Pages 1102-1107
Published: September 05, 1968
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSThe first attempt to analyze mixed alkoxyl group in micro-quantities, employing gaschromatography and mole-ratio calculation method, was made by Mitsui in 1963. Further reformations were made by the present authors and each alkoxyl group was estimated from direct calibration curves of peak areas (by HW/2 method) with standard deviation of σ=0.30.7 from methoxyl to propoxyl groups.
At the initial stage of the authors' experiment, the sample was digested and alkyl iodides thus formed were collected in an absorption tube according to Mitsui's method. Ten per cent Apiezon L coated silica gel (3060 mesh) was applied as an absorber instead of silica gel. This modified absorber was quite sufficient for quantitative absorption and desorption of alkyl iodides. In the second, the absorption tube was heated to 150160°C on a stationary furnace as shown in Fig. 1, and vaporized alkyl iodides were introduced to a gaschromatograph. The gaschromatographic separation of mixed alkyl iodides were carried out as in Fig. 6, and calibration curves for the components were obtained from their peak areas (Fig. 7). Analytical results were summarized in Tables VVI.
The method of analysis and the problems related were described in this paper.View full abstractDownload PDF (880K) -
Hisao OSAWA1968 Volume 17 Issue 9 Pages 1108-1115
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe relations between vaporized amounts, vaporization behavior and spectral line intensity of gold in graphite powder have been examined with graphite electrodes under varying arc discharge conditions and buffer concentrations.
Standard samples were prepared with highly purified graphite powder, 100 ppm of gold as auric chloride and various amounts of lithium fluoride as a spectrographic buffer substance. The element was excited by d. c. arc discharge, and the concentration of gold remaining in graphite powder after the dischage was measured by the neutron activation analysis.
It was clarified that the vaporized amounts and vaporization behavior depended mostly on the electrode temperature. As an arc current increased, the vaporized amounts increased and the temperature of an anode was raised. Under the experimental conditions including d. c. 14.4A, 14.6V, discharge time 60 sec, electrode gap 3 mm, and 2.0% of lithium fluoride, the vaporized amounts were 2×10-8 g/mg sample at the anode crater in argon atmosphere, and 6.8×10-8 g/mg sample at the anode crater in helium atmosphere.
The emission line intensity of Au:2675.9Å depended on the vaporized amounts of gold in argon atmosphere, but not depended on the vaporized amounts of gold in helium atmosphere.View full abstractDownload PDF (1090K) -
Analytical studies on drugs by infrared spectroscopy. VI.Masayoshi TATSUZAWA, Shigeko HASHIBA, Akira OKAWARA1968 Volume 17 Issue 9 Pages 1116-1118
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDetermination by infrared spectrometry and identification by thin layer chromatography and infrared spectrometry have been developed for dibucaine and t-caine in mixed preparations. Dibucaine and t-caine could be determined from their absorption in chloroform, respectively, at 1670 cm-1 and 1705 cm-1 as the key bands, according to the base line technique.
Identification: A mixed sample is taken in a separatory funnel. Five milliliters of NaOH TS is added, and it is extracted with ethylether.
The extract is evaporated almost to dryness, and dissolved in methanol.
A portion of the solution is applied to a Kieselgel G plate, and is developed with ethylacetate-ethylether-30% ammonia (80 : 20 : 1). After being extracted with methanol-chloroform (3 : 7) and evaporated on a water bath, dibucaine and t-caine are identified by their infrared spectra (by KBr disk method and liquid film method).
Assay : A mixed sample (containing 100 mg of dibucaine or t-caine) is taken in a separatory funnel. Five milliliters of NaOH TS (NaCl saturated) is added, and it is extracted 4 times with 10 ml portions of chloroform. The combined extract is made up exactly to 50 ml with chloroform. The absorbance is measured at 1670cm-1, or 1705cm-1 (ET ) against chloroform. The absorbance of standard solution (ES ) is measured at the same time, and the amount of dibucaine or t-caine is calculated by ET /ES.
A sample containing 20 mg of dibucaine or t-caine can be determined by making up the combined extract exactly to 10 ml with chloroform with preliminary concentration by evaporation.View full abstractDownload PDF (514K) -
Nobuyoshi YAMAGUCHI, Akihisa HATA, Minoru HASEGAWA1968 Volume 17 Issue 9 Pages 1118-1121
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA rapid spectrophotometric determinati on fo Sn and As in ferrotungsten using solvent extraction has been carried out as follows.
Take up 0.5 g of sample with hydrogen peroxide water and hydrofluoric acid, and evaporate to fumes with sulfuric acid. Add, after cooling, an amount of Be2+ and EDTA solution. Neutralize with ammonia water, and then add 10 ml in excess. Boil for 12 min., allow to cool and filter. Dissolve the precipitate with 10N sulfuric acid, and transfer the solution into a separatory funnel. Add potassium iodide solution and benzene, and extract Sn and As by shaking for 2 min. After washing the benzene layer with mixture of sulfuric acid and potassium iodide solution, back-extract Sn and As by shaking with 0.8N sulfuric acid, and made up to 50 ml. For the determination of Sn, add to an aliquot sodium sulfite, the buffer solution, gum arabic and phenylfluorone solution, and measure the absorbance at 510 mμ. For the determination of As, add potassium permanganate, ammonium molybdate solution and hydrazine sulfate solution, and heat in a boiling water bath. Measure the absorbance at 850 mμ.
The method is applicable equally for tungsten ores, provided that the sample is taken up with sodium peroxide.View full abstractDownload PDF (753K) -
Koji ISHIDA, Takao ITO, Rokuro KURODA1968 Volume 17 Issue 9 Pages 1122-1123
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThin-layer chromatographic behavior of Sc, rare earths, Th and U (VI) on a microcrystalline cellulose plate in n-butanol-nitric acid system was described. The Rf values of these metal ions were measured as functions of the concentration of nitric acid and of the volume ratios of the two phases.
The best results for a separation of the four metal ions were obtained on the system consisting of n-butanol : 10N HNO3=5 : 3, in which the Rf value was in the order, U>Th>Sc>Sm. The separation was achieved by raising the developing solvent 6.5cm high within about 90 minutes.View full abstractDownload PDF (347K) -
Masakazu DEGUCHI1968 Volume 17 Issue 9 Pages 1124-1126
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA method of spot test for cadmium has been proposed, by using a rapid reaction of cadmium and 2, 2'-bisbenzothiazoline to form a red-violet complex in alkaline medium. A drop of neutral solution of the sample was taken on a white spot plate, each one drop of both buffer solution (pH 13.0) and 1% 2, 2'-bisbenzothiazoline solution in dioxane was added and mixed thoroughly. The presence of cadmium gave red-violet precipitate. The limit of detection was 0.1 μg. Nickel, cobalt, copper, zinc and mercury interfered with the reaction, but their permissible amounts could be increased by addition of potassium cyanide and formaldehyde. Good results were obtained for synthetic samples.View full abstractDownload PDF (428K) -
Akira YAMAMOTO, Junichi AKIYAMA, Takayuki OKINO1968 Volume 17 Issue 9 Pages 1126-1128
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe authors have already reported on the detector sensitivity and quantitative analysis of the micro differential thermal analysis. The characteristics of the micro D.T.A. were mainly in free diffusion of the evolving gases from the small volume of the sample in thin layer, the obtained thermograms being remarkably different from those by the macro D.T.A. For instance, the former gave 3 peaks for 0.5mg of SrCl2·6H2O, while the latter gave 4 peaks for 25 mg of the same material. By sealing the sample container, the peaks combined to one. These results, together with detailed studies on those peaks by macro and micro thermobalances, showed that the dehydration process was influenced greatly by the vapor pressure of water in the interior of the sample solid.View full abstractDownload PDF (425K) -
Wataru MACHIDA, Tadao OKUTANI, Satori UTSUMI1968 Volume 17 Issue 9 Pages 1128-1130
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA simple spectrophotometric method for the determination of a small amount of sulfur in heavy oil has been proposed.
An amount of heavy oil is diluted with toluene, and 10 μl of the diluted solution is transfered through a microsyringe onto a filter paper strip on a platinum wire. The paper is burned in an oxygen flask, and sulfur dioxide formed is absorbed in a definite amount of an aqueous solution of mercuric nitrate and potassium bromide. An aliquot of this solution is transfered into a brown separatory funnel, and is shaken with a buffer solution (pH 7), benzene and an ethanol solution of diphenyl-carbazone. Sulfur in heavy oil can be thus determined with satisfactory results by measuring the absorbancy of the benzene phase at 562 mμ, refereing to the calibration curve prepared beforehand.View full abstractDownload PDF (465K) -
Yasuhiro YAMANE, Motoichi MIYAZAKI, Hiroshi IWASE1968 Volume 17 Issue 9 Pages 1131-1132
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe separation and identification of Al, Be, and Cr ions were studied by thin layer chromatography.
These three ions were completely separated by the solvent system, ethanol : 1 N HNO3 (99 : 1) using a purified silica gel plate of 0.25 mm thickness containing 5 per cent amount of soluble starch.
Al and Be were identified by the fluorescence of their oxinates under ultra-violet rays, and Cr was detected as its diphenylcarbazide complex after being oxidized with H2O2 in an alkaline medium.
Several common anions which might be considered to interfere the separation and identification of the three metal ions were also investigated.View full abstractDownload PDF (361K) -
Wataru FUNASAKA, Teiichi ANDO, Yoshiro TOMIDA1968 Volume 17 Issue 9 Pages 1133-1136
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSLanthanum in rare earth oxide mixtures was determined by three X-ray fluorescence methods : addition method, direct comparison method, and internal standard method. By the last method with barium as internal standard, lanthanum and cerium could be determined simultaneously with no influence of co-existing thorium.
The results obtained by the above three methods were in good agreement with one another. The validity of the lanthanum contents thus determined was supported by the results of lanthanum oxide addition experiments and of chemical analysis of cerium, as well as by the consideration on the "infinitely diluted state."View full abstractDownload PDF (792K) -
Hiroshi HASHITANI, Hideyo YOSHIDA1968 Volume 17 Issue 9 Pages 1136-1139
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe sensitive photometric method, using thymol, reported by Roskam and de Langen {Anal. Chim. Acta, 30, 56 (1964)}, has been examined, and the following factors were found to be important in this method : (1) The pH of the solution at the step of adding hypochlorite (pH 9.810.3), (2) the time interval between the addition of hypochlorite and that of thymol (within 30 seconds), and (3) the pH of the colored solution (pH 11.511.9).
The maximum color intensity was attained after 60 minutes and remained constant for at least 5 hours, when the solution was stored in dark place. No effect of temperature was observed in the range of 530°C. The absorbance per 1 μg nitrogen was 0.0165 (molar absorptivity=1.16×104) at 660 mμ by the following established procedure:
Sodium hydroxide solution (1 M) is added to a weakly acidic sample solution (less than 30 ml) containing 36 μg of ammonia nitrogen, to which has been added one drop of phenolphthalein solution (0.1%), until pink color appears, and then 2 ml of sodium bicarbonate (0.06M)-sodium carbonate (0.075M) buffer solutions added to adjust the pH to 10. Then, 0.2 ml of sodium hypochlorite solution containing 0.3% active chlorine is added to the solution. After 20 seconds, 2.5 ml of a freshly prepared mixture of the equal volumes of thymol solution(10% in acetone) and sodium hydroxide solution (0.9M) is added to it. The resultant solution is transferred to a 50 ml measuring flask, and diluted to the mark with water. After standing for 1 hour in darkness, the absorbance of the colored solution is measured against the blank at 660 mμ.View full abstractDownload PDF (698K) -
Hiroshi KAWAMOTO1968 Volume 17 Issue 9 Pages 1139-1141
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSSynergistic extraction with a mixture of 2-thenoyl-trifluoroacetone (TTA) and pyridine in benzene was employed for the spectrophotometric determination of cobalt (II). The pH of a sample solution containing up to 100 μg of Co (II) was adjusted to 5.5. After the addition of TTA and pyridine-benzene solution, cobalt was extracted into benzene, and the absorbance of the organic phase was measured at 390 mμ. The sensitivity of this method was 0.033 μg-Co/cm2, and the relative error for 50 μg of Co was smaller than 2%. Although interference from iron (III) and copper (II) could be eliminated by adding fluoride and thiosulfate ions that from nickel was serious.View full abstractDownload PDF (442K) -
Masato KOTAKEMORI, Sigeru YAMAMOTO, Sigeo HISADA, Mituru ANDO1968 Volume 17 Issue 9 Pages 1142-1143
Published: September 05, 1968
Released on J-STAGE: May 07, 2010
JOURNAL FREE ACCESSAn oxygen-flask combustion of hair replaces wet ashing prior to the determination of mercury, copper and zinc. After 0.5 g of hair has been burned in an oxygen-filled flask, of 1, 000 ml capacity, the metals are absorbed in 2.5 N sulfuric acid solution. Then, the metals of lower oxidation state in the absorbing solution were oxidized with potassium permanganate.
The mercury was determined spectrophotometrically with dithizone by a slight modification of Ukita's method. Interference from zinc, disregarded by other workers, has been studied and excluded by masking with EDTA. The copper and zinc was determined spectrophotometrically with dithizone and sodium diethyldithiocarbamate, respectively.
The mercury of 1 ppm or above in hair could be determined with a variation coefficient about 3%, and the relative experimental error was nearly 5% in the presence of 145279 ppm of copper and 84250 ppm of zinc.View full abstractDownload PDF (333K) -
Tomihito KAMBARA, Shigeyuki TANAKA, Kenjiro FUKADA1968 Volume 17 Issue 9 Pages 1144-1146
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe oxidation of iodide ion to iodine by hydrogen peroxide is catalysed by molybdenum(VI). The D. C. polarographic wave height of iodide in the solution, which is 4.78 mM in hydrogen peroxide, 0.4 mM in potassium iodide, 1M in sulfuric acid and 0.06% in gelatin, is traced at the potential of +0.2 V vs. mercury pool cathode. The logarithm of the iodide diffusion current id is plotted against time, resulting in a straight line, the slope of which shows a linear relationship with the amount of molybdenum(VI) in the electrolysis solution. By means of the present chronoamperometric method, the molybdenum(VI) in a microgram amount can be determined.View full abstractDownload PDF (349K) -
Hitoshi KOHARA1968 Volume 17 Issue 9 Pages 1147-1148
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe interaction between acidic dye molecule and positive charges on the micelle surface has been investigated. The protolytic dissociation of acidic dye molecule containing a hydroxyl group on one end of the conjugated system and nitro or carbonyl group on the other end is promoted on the micelle surface. The interaction between dipole of acidic dye molecule and positive charges on the micelle surface causes a transfer of an electron from the electrondonating group to the electron-attracting group. The effect of quaternary ammonium salt on the acid strength increases with the increase of the dissociation constant of hydroxyl group on the dye molecule. The increase of ionic strength and the decrease of dielectric constant weaken the interaction. With the quaternary ammonium salt, the lower the critical micelle concentration, the stronger is the interaction between dye molecule and micelle. Dye molecules or ligands involving -SO3H group are liable to be absorbed on the micelle surface. It is found that the complexes of higher order are readily formed on the micelle surface, and the analytical sensitivity increases if the absorption of the complex is due to π→π* transition of organic ligands.View full abstractDownload PDF (323K) -
Shigeru SHIMOMURA, Yoichi NISHIHARA, Yaichiro TANASE1968 Volume 17 Issue 9 Pages 1148-1149
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIt was found that the count of diluted mercuric-203 chloride solution was slowly decreased after it was alkalified with sodium hydroxide. This decrease was avoided by the addition of such oxidant as potassium permanganate or sodium hypochlorite, but was not by the addition of chloride ion.View full abstractDownload PDF (322K) -
1968 Volume 17 Issue 9 Pages 1150-1159
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDownload PDF (1905K) -
[in Japanese]1968 Volume 17 Issue 9 Pages 1160-1165
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDownload PDF (1028K) -
[in Japanese]1968 Volume 17 Issue 9 Pages 1166-1167
Published: September 05, 1968
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDownload PDF (212K)
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