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Volume 33, Issue 5
Displaying 1-20 of 20 articles from this issue
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Shoji MURAI, Takami OZAWA, Yasuyuki MAKI1984 Volume 33 Issue 5 Pages 229-233
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIt is very important to know the amounts of Cl-and SO42- in water-soluble ink for ball-point pens because large amounts of these ions cause various troubles such as blurring and precipitating. The capillary tube isotachophoresis has been applied to the simultaneous determination of Cl- and SO42- in ink. In order to determine the optimum conditions for the separation of these ions, three electrolyte systems have been investigated; (I) : the leading electrolye (L) contains 5 mM cadmium nitrate and acetone, the terminal electrolyte (T) contains 5 mM hexanoic acid, (II) : (L) 5 mM cadmium nitrate and ethanol, (T) 5 mM hexanoic acid, (III) : (L) 5 mM calcium hydroxide, (T) 5 mM hexanoic acid. Cl- and SO42- in the standard solution are determined successfully with each electrolyte system. For both electrolyte (I) and (II), the more the amount of solvent increases, the more the potential unit (PU) values of Cl- and SO42- increase, and therefore, these ions are separated more clearly. PU values vary as follows : no organic solvent, Cl- : 0.03, SO42-: 0.06, 50 % of acetone, 0.27, 0.55, 50 % of ethanol, 0.13, 0.62. In case that 20 % of acetone or ethanol is added, Cl- and SO42- in ink can be separated and determined. Adding above 30 % of these organic solvents, SO42- is separated from Cl- but not separated from the sulfinate dyes in ink. The dyes become insoluble in the electrolyte (I) and (II), and stick to the capillary tube and detector as each electrolyte is acidic. On the contrary, electrolyte system (III) which is basic gives good results for basic ink. Cl- and SO42- are separated without interferences of the dyes. PU values are also high (Cl- : 0.24, SO42- : 0.32). The detection limit of Cl- and SO42- by the present method is 3 ppm.View full abstractDownload PDF (1058K) -
Tomiki TAKAHASHI, Sumio OHOKOSHI, Nariko SHINRIKI, Toshio SATO1984 Volume 33 Issue 5 Pages 233-236
Published: May 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSFor a rapid and handy determination of heavy water in light water, the principle based on the isotopic exchange reaction between liquid water and hydrogen, resulting in the formation of HD which is detected by gas chromatography was applied. The catalyst which promotes the exchange reaction at room temperature and atomospheric pressure, was 2 % Pt coated on HD4 type styrene-divinyl benzene copolymer. The preparation method was as follows : platinic chloride-ethanol solution of 1 g Pt/l was impregnated carefully to the styrene-divinyl benzene copolymer (particle size : 177250 μm), and the mixture was dried at 80100 °C in air, then heated at 230 °C for 20 h under hydrogen stream. This catalyst does not lose its catalytic activities for long time after bringing it into contact with liquid water because of its hydrophobic property. When it loses its activities, it can be easily activated by exposure to air or oxygen for 5 min. A greaseless closed circulation reactor made of glass was used for the liquid water-hydrogen exchange reaction. At the top of the coiled reactor (4 mm × 3 m), 0.2 g of catalyst was set, and stainless steel Dixon packing (φ 3 mm) was set at the bottom of the reactor, and sufficient mixing of sample liquid water (0.42 ml), water vapor, and hydrogen was carried out. Hydrogen gas (175 ml) was circulated by a flow rate of 2 1/min. Analysis of HD produced was performed by a gas chromatograph which was directly connected to the reactor. This method can be applied to the analysis of heavy water in concentration ranges from 0.01 % to 99.5 % and it requires 30 min. The error was 1 % in the range of high concentration of heavy water, and was 2 % and 3 % in the case of the content of heavy water of 2.5 % and of 0.030.01 %, respectively.View full abstractDownload PDF (789K) -
Ken MATSUMOTO, Hidemi KOSHIISHI, Kikuo TERADA1984 Volume 33 Issue 5 Pages 237-241
Published: May 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA simple, fast and accurate method for the determination of tin(IV) oxide in high purity tin metals has been developed. A 50 ml of 14 % (w/v) potassium copper (II) chloride solution containing 0.4 % (w/v) of tartaric acid was put in a 100 ml separatory funnel, and nitrogen was passed through for 10 min at a rate of 700 ml min-1 to remove oxygen. In a nitrogen atmosphere a sample of tin metal, usually 200300 mg in weight, was added and the funnel was stoppered and immediately shaken vigorously for 30 min : the metal dissolved in the solution, while the oxide remained as insoluble residue. The tin(IV) oxide was collected quantitatively on a small sintered glass filter (G4) (3.6 cm × 1.4 cm o.d.) under suction and washed first with potassium copper (II) chloride solution, then with water, and finally with ethanol, and dried. The filter and tin (IV) oxide were placed in a decomposition tube (borosilicate-glass, 5 cm × 1.8 cm o.d.) ; 2 g of ammonium iodide was then added in the same tube, followed by a small piece of platinum wire as catalyst, and the tube was attached to a cold trap (borosilicate-glass, 40 cm × 1.8 cm o.d.). The decomposition tube was gently heated with a fish-tail burner for about 1 min; the sublimate, tin(IV) iodide, was quantitatively collected in the trap. After evolution of iodine had ceased, the tin(IV) iodide was dissolved with 0.5 M hydrochloric acid and the concentration of tin in the resulting solution was determined by graphite furnace atomic absorption spectrometry at the 224.6 nm. This method was applied to commercial high purity tin metal of various forms, and 0.014 to 1.01 % of tin (IV) oxide could be determined with good reproducibility.View full abstractDownload PDF (1008K) -
Tetsuo UCHIDA, Chuzo IIDA, Kazuo YAMASAKI, Shigeto KANAOKA, Yoshihisa ...1984 Volume 33 Issue 5 Pages 242-247
Published: May 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSMulti-channel inductively coupled plasma (I.C.P.) emission spectrometry was applied to the determination of silicon, aluminium, iron, titanium, manganese, calcium, magnesium, sodium, and potassium in milligram amounts of silicate sample. Alkali elements were compelled to determine by flame emission spectrometry with one-drop method using the same sample solution because of the poor reproducibility in I.C.P. measurements especially for potassium. The optimum concentration of boric acid for the masking of fluoride ion used for sample decomposition was chosen for the stable and reproducible measurements. About 25 mg of powdered sample was decomposed with 0.5 ml hydrochloric and 0.25 ml hydrofluoric acids in a small sealed Teflon vessel at room temperature for overnight. After the addition of 6 ml of 4 % boric acid, sample solution was made up to 50 g with water and served for measurements. All sample and standard solutions were prepared not by volumetric but by gravimetric method. Recalibration by standard solutions should be carried out every 30 min for accurate determinations. By the use of 25 decomposition vessels, only one week was required for the analyses of 100 samples by two operators including the preparation of standard and sample solutions. The accuracy and reproducibility of the present method were 98103 % and 2 % respectively.View full abstractDownload PDF (1197K) -
Analytical application of Ο, Ο'-dialkyldithiophosphate IKenjiro HAYASHI, Yoshiaki SASAKI, Shoji TAGASHIRA, Shigehiro INOMATA, ...1984 Volume 33 Issue 5 Pages 247-252
Published: May 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSIt was found that the addition of hydrogen peroxide led to improvement in the reproducibility and the sensitivity in the extraction-spectrophotometry for iron(III) and copper(II) with diethyldithiophosphate (dtp-). As a result, the determination method for these metal ions was investigated in the presence of hydrogen peroxide. The iron and copper complexes extracted into hexane gave the absorption spectra having maxima at the wavelength of 360, 490, and 590 nm and having a maximum at 419 nm, respectively. The optimum conditions of pH and the concentrations of hydrogen peroxide and Kdtp for the determination of iron at 590 nm were 1.5 3, 0.0060.02 mol dm-3, and 0.050.3 mol dm-3, respectively. And, those for copper at 419 nm were 06, 0.0050.02 mol dm-3, and 0.020.3 mol dm-3, respectively. By the extraction into 10 cm3 of hexane from 10 cm3 of the aqueous phase containing 0.01 mol dm-3 hydrogen peroxide and 0.1 mol dm-3 Kdtp at pH 2, (5×10-6 3×10-4) mol dm-3 iron and (2.5×10-6 1×10-4) mol dm-3 copper were extracted quantitatively and the absorbance of hexane phase against pure solvent followed Beer's law. The molar absorptivities of the iron and copper complexes were 3.54×103 (at 590 nm) and 1.26×104 mol-1 dm3 cm-1 (at 419 nm), respectively. The interfering ions in the determination of iron were copper(II), cadmium(II), lead (II), silver(I), and oxalate. And, those ions for copper were cadmium (II), lead (II), silver(I), tellurium (IV), and osmium (VIII). The ligand was hardly oxidized with hydrogen peroxide at the above conditions, the effect of the addition of hydrogen peroxide may be due to suppressing the reduction of metal ions with dtp-. [Fe (dtp)3] was estimated as a species extracted on the basis of the relation between the distribution ratio of iron and the ligand concentration. The distribution constant and the overall formation constant for this complex were also determined as 51.9 and 1.95 ×104, respectively. The extraction mechanism for copper was complicated.View full abstractDownload PDF (1130K) -
Yoshimitsu SEO1984 Volume 33 Issue 5 Pages 252-256
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSAtomic ratio of C/Br and Cl/Br in various halogen organic compounds was determined by gas chromatograph with a detecting system consisted of conventional hydrogen flame ionization detector and dual ionselective electrode of chloride and bromide. Compounds eluted from a GC column (Durapak-Carbowax 400/Porasil C, 100120 mesh, 1000 × 3 mm, i.d.) are passed through a heated silica tube (1000 × 0.5 mm i.d.) packed with platinum wire, where they undergo a hydrogenolysis, and chlorine compounds are converted to hydrogen chloride, bromine compounds to hydrogen bromide and carbon compounds, to methane. The decomposition gases are split into two parts (1 : 1). One part is passed through a granular silver absorber which removes hydrogen chloride and hydrogen bromide from gases and introduced a flame ionization detector cell. Another is passed through a dual ionselective electrode detector cell, and the concentration of chloride and bromide was determined. Since the response of the flame ionization detector was directly proportional to the number of carbon in molecule, C/Br or Cl/Br ratios were determined for seven bromochloroalkanes. Fairly good agreement was found between the theoretical and found values.View full abstractDownload PDF (915K) -
Toshiyuki MITSUI, Yukio MINAMI, Yoshikazu FUJIMURA1984 Volume 33 Issue 5 Pages 257-260
Published: May 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe low molecular weight primary and secondary amines cannot be extracted by ion association reagent (Tropaeoline OO) and cannot be determined by spectrophotometric method. But the low molecular weight primary and secondary amines react with 13 kinds of benzylchlorides to form their derivatives, which are extracted into chloroform or dichloromethane at pH 2.09 in the presence of Tropaeoline OO forming an ion association complex. The procedure is as follows; Place 1 ml of the sample solution, 30.0 mg of benzylchlorides, 10 ml of acetone, and 5 ml of 3 % sodium carbonate solution in a 20 ml Erlenmyer's flask. Warm it in a water bath for 15 min on adding acetone, and for 15 min without adding acetone at 80 ± 3°C. After cooling, add 10 ml of chloroform or dichloromethane. Shake it for 30 s and place it a 15 ml test tube. Centrifuge for 2 min at 3000 rpm. In a 15 ml test tube, place 5 ml of the organic phase, 1 ml of a saturated Tropaeoline OO solution, and 2 ml of a buffer solution (pH 2.09). Shake the solution for 2 min mechanically, and centrifuge for 2 min. Take 2 ml of the organic phase, and add 0.5 ml of methanol solution of 10 % hydrochloric acid and measure the absorbance at 543 nm. α-Chloro-p-xylene, p-ethyl benzylchloride, 3, 4-dimethyl benzylchloride, and 2, 5-dimethyl benzylchloride produce the hexylamine derivatives which are high sensitive for spectrophotometric determination.View full abstractDownload PDF (798K) -
Chozo YOSHIMURA, Toshihiko NISHIGUCHI1984 Volume 33 Issue 5 Pages 261-265
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe reactions between inorganic nitrites or hydrogen peroxide and pyridine-perchloric acid adduct were investigated by conductimetric and potentiometric titration in N, N-dimethylformamide (DMF). DMF was used as an excellent solvent on account of having high solubilities for inorganic nitrites and adduct. The sample solutions were prepared by dissolving required quantity of inorganic nitrites, hydrogen peroxide in DMF, and standardizations were carried out with permanganate method and iodometry. The used inorganic nitrites were sodium(I) nitrite, calcium(II) nitrite and barium(II) nitrite. On titration of the inorganic nitrites with pyridine-perchloric acid adduct by conductimetry or potentiometry, the combination ratios of 1 : 1 or 1 : 2 on titration curves. The end point of reaction between hydrogen peroxide and the adduct could be detected by potentiometry, but not be obtained a inflection point by conductimetry. And the combination ratio was obtained at the molar ratio of 4 : 1 by potentiometric titration. From the results, it was considered that the reactions between nitrite ions or hydrogen peroxide and the adduct were redox reaction in basic solvents, and these reactions did not proceed by increasing acidity of the sample solutions. Less than 1 v/v % of water gave no influence on the obtained end points. The limiting concentration of the determination were different owing to sort of inorganic nitrites, but were about from 1×10-4 mol dm-3 to 5×10-4 mol dm-3.View full abstractDownload PDF (945K) -
Hisomu NAGASHIMA, Wataru MACHIDA, Satori UTSUMI1984 Volume 33 Issue 5 Pages 265-270
Published: May 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA quality test method of commercially available diphenylcarbazone (DPCO) reagent, which has been used as an indicator of mercury(II) titration, was established by high performance liquid chromatography (HPLC). The purified compounds of DPCO, diphenylcarbazide (DPCI), diphenylcarbadiazone(DPCDO), and phenylsemicarbazide(PSCI) were used as standards. A portion of the standard solution or commercial DPCO solution was injected into a HPLC system equipped with μ Bondapak C18 column (3.9 mm i.d. × 30 cm) and UV detector (254 nm) and eluted with methanol1 M acetic acid (40 60). Each compound was successfully separated and could be determined by using a linear calibration curve based on the peak area method. Commercially available DPCO reagent contained 1151 % of DPCO, 4857 % of DPCI, 030 % of PSCI, and trace amounts of DPCDO. Since the reagents containing less than 30 % of DPCO didn't give clear end point in the titration of halide with mercury(II), satisfactory qualitative DPCO reagent were prepared by air oxidation of DPCI in alkaline alcoholic solution at 50 °C. DPCO was unstable in ethanol solution and decomposed to DPCDO, but stable for 2 months in the presence of 3050 % of DPCI in the solution. The titration of halide with mercury(II) was satisfactorily carried out by using the mixed solution (5070 % DPCO and 5030 % DPCI) as an indicator.View full abstractDownload PDF (1096K) -
II. Effects of flame composition and some other salts on S2 emission responseKoichi NAKAJIMA, Takeo TAKADA1984 Volume 33 Issue 5 Pages 271-275
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSEffect of flame composition on S2 emission intensity in molecular emission cavity analysis was investigated using a nitrogen sheath oxy-hydrogen flame. S2 emission intensity was dependent on oxygen flow rate. The integral intensity varied significantly with it. Optimum oxygen flow rates are 0.33 l min-1 for integral intensity and 0.22 l min-1 for peak height, at which flame temperatures are 980 °C and 830 °C, respectively. In spite of the little variation of flame temperature with flame height, the position of the cavity in the flame had marked effects on the S2 emission response. With increase in the distance of the cavity from the burner head, the peak height decreased, but the integral intensity increased. The peak height of S2 emission from thiosulfate was dependent on hydrogen flow rate. The peak height was increased with increase in hydrogen flow rate, but the integral intensity was not dependent. In the case of sulfuric acid, the increasing of hydrogen flow rate increased the integral intensity and made the calibration plot linear. From these results, it is expected that hydrogen radical takes part in the decomposition of sulfur-containing compounds. Addition of some other ammonium salts to sulfate sample brought about the quenching effect, which seemed to depend on some characteristics of the species in the sample, e.g. concentration, decomposition temperature and fragments.View full abstractDownload PDF (865K) -
Takashi SAITO, Toru TAKASHINA, Shunsaku HIGASHI, Saburo YANAGISAWA, Ts ...1984 Volume 33 Issue 5 Pages 276-280
Published: May 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThis paper describes an analytical method of phenolic resins in piled particulate matters on the road. Samples of particulate matters were washed with ethanol and benzene, dried at room temperature, and then 5 mg of the particulate matter was applied to the Hitachi 063 type pyrolysis gas chromatograph equipped with a KP-1 pyrolyzer. Since a good linear calibration curve was obtained from relationships between the amount of phenolic resin and the peak height of phenol in its pyrogram, phenolic resins in piled particulate matters could easily be determined from their pyrograms. The concentrations of phenolic resins in the piled particulate matters collected at service area, toll gate, and tunnel of expressway were 1.9 mg/g, 1.6 mg/g, and 0.98 mg/g, respectively. Most parts of phenolic resins in the piled particulate matters on the expressway are presumed to be emitted from the brake lining of motor vehicles, because the usual brake lining material is composed of phenolic resins, asbestos, oils, etc. A brake lining material was analyzed by this method and the content of phenolic resin in the brake lining material was found to be 11 %. Therefore, assuming the brake lining material of motor vehicles in general use contains about 11 % of phenolic resins, the piled particulate matters collected at the expressway were estimated to contain about 0.89 to 1.7 % of brake lining materials. The proposed method will be useful as simple determination method to roughly estimate phenolic resin content in piled particulate matter.View full abstractDownload PDF (826K) -
Koichi OGUMA, Shu ISHINO, Rokuro KURODA1984 Volume 33 Issue 5 Pages 280-284
Published: May 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA spectrophotometric method was developed for the determination of calcium in silicate rocks by using ο- cresolphthalein complexone(CPC). Fifty mg of powdered rock sample was fused with a mixture of 150 mg of anhydrous lithium carbonate and 150 mg of boric acid. The cake was dissolved in 1 M hydrochloric acid and diluted to 100 ml with the same acid. A 1-ml aliquot of the resulting solution was passed through a column (φ 15 mm, bed height 30 mm) containing 1 g of cellulose phosphate to remove polyvalent cations including aluminum, iron(III), titanium(IV), etc. Calcium in the effluent was determined spectrophotometrically with CPC by using 8-quinolinol as a masking agent for magnesium. The combined ion-exchange-spectrophotometric method was applied to the determination of calcium in a variety of standard rock samples totalling 14 of the U. S. Geological Survey and of the Geological Survey of Japan. The results were in good agreement with the recommended or reported values. Results were also quoted on the determination of calcium in five, environmental biological standard reference materials including Orchard leaves (NBS), Pepperbush, Chlorella, Mussel, and Hair (National Institute for Environmental Studies). The relative standard deviation (n=3 or 4) ranged from 0.3 to 2.8 %.View full abstractDownload PDF (842K) -
Kazutoshi TANABE, Jiro HIRAISHI, Tadao TAMURA, Osamu YAMAMOTO, Masaru ...1984 Volume 33 Issue 5 Pages 285-287
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSAs a continuation of the preceding paper, several points have been considered on the combined search by infrared, 13C-nuclear magnetic resonance, and mass spectral data. The effect on the noise ratio in the search result of the threshold value of peak intensity in the coding has at first been examined, and it has been found that the appropriate threshold value is 50. Next, the effect of the number of input peaks has been considered, and it has been found that if data of two peaks per spectrum are entered and the threshold value of 50 is used, the noise ratio in the combined search is 0.01 %. It has been concluded from these facts that the combined search is effective for the identification of the correct answer from 10000 compounds.View full abstractDownload PDF (428K) -
Noboru IMAI, Shigeru TERASHIMA, Atsushi ANDO1984 Volume 33 Issue 5 Pages 288-290
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA hydride generation-atomic absorption method for the rapid and precise determination of selenium in geological materials is described. The rock and soil samples of 0.10.5 g were decomposed with HClO4, HNO3, and HF, then evaporated nearly to dryness. The residue was dissolved by diluted HCl, and added iron (III) (25 mg) chloride solution, and then diluted to 25 ml with water. For coals, 0.050.1 g of sample was digested with HCl and HNO3 at 130 °C for 5 h, and then also digested with HF. Selenium hydride was generated with 1 % sodium tetrahydroborate and 6 M hydrochloric acid using an automated hydride generator, and introduced to a quartz cell atomizer. Most serious interferences occur from copper, nickel, arsenic, and tin, but the interferences were eliminated by the addition of iron(III). For high ash coal sample, slightly lower selenium values were observed in the procedure of the low temperature oxygen plasma ashing. The detection limit is 0.01 ppm for 0.5 g of a given sample, and the relative standard deviation in the determination of more than 0.1 ppm is less than 12 %. The method is satisfactorily applied to the analyses of selenium in geological reference rock, soil, and coal samples.View full abstractDownload PDF (672K) -
Kenichi HIMENO, Kazuhiro YANAGISAWA, Toyohiro YUKI, Yasushi NAKAMURA1984 Volume 33 Issue 5 Pages T43-T46
Published: May 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe elements, Cu, Pb, Zn, Cd, Ni, Cr, Mn, Sb, As, and Fe, in waste water determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES), after coprecipitation with lanthanum hydroxide. The sample solution was digested with 5 ml of hydrochloric acid and 5 ml of nitric acid. After cooling, 3 ml of 3 % lanthanum nitrate solution was added, and pH was adjusted to between 1012 with 3 M sodium hydroxide solution. The hydroxide precipitate was collected on a membrane filter (pore size 1.2 μm, diameter 47 mm), and washed with distilled water. The precipitate was dissolved with 5 ml of hydrochloric acid (1+1) in the original beaker and diluted to 20 ml with distilled water. Ten elements were determined by ICP-AES. The interference from lanthanum was corrected by substracting the intensity of a blank solution added the same quantity of lanthanum. The interference from magnesium was corrected by calculation with magnesium content in the final test solution. Relative standard deviations of the analysis were less than 10 % (for 0.05 mg/l) and 4.2 % (for 0.50 mg/l).View full abstractDownload PDF (808K) -
Y.K. Agrawal, K.T. John1984 Volume 33 Issue 5 Pages E137-E142
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA sensitive and selective method for the solvent extraction and spectrophotometric determination of cerium(IV) with N-p-Chlorophenyl 3, 4, 5-trimethoxycinnamohydroxamic acid has been described. It forms a reddish brown coloured complex with cerium(IV) which can be extracted into chloroform at pH 9-10 and the molar absorptivity is 8.5 × 103 dm3 mol-1 cm-1 at 465 nm. The effects of pH, reagent concentration, extraction time and stability of the complex are discussed.View full abstractDownload PDF (719K) -
Junichi SHIDA, Yoshiko TAKAHASHI, Koichi OJIMA, Tsutomu MATSUO1984 Volume 33 Issue 5 Pages E143-E149
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA precise and accurate method based on the flotation-spectrophotometry has been developed for the microdetermination of germanium in coal fly ash. The germanium-phenylfluorone complex was floated with cyclohexane at the phase boundary and separated from the excess reagent by removing the aqueous phase. Cyclohexane was a suitable extractant for the separation of germanium tetrachloride from foreign ions. Extractability of germanium was 90.3 ± 0.5 %. Coal fly ash was treated with aqua regia and hydrofluoric acid in a teflon decomposition vessel, and germanium was determined as phenylfluorone complex in a cyclohexane-ethanol medium at 505 nm. The absorbance of the reagent blank was 0.010 ± 0.002. The accuracy of the proposed method was studied by analyzing synthetic samples and NBS 1633 coal fly ash.View full abstractDownload PDF (826K) -
M.A. CEJAS, A. GOMEZ-HENS, M. VALCARCEL1984 Volume 33 Issue 5 Pages E151-E157
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSAn indirect kinetic fluorimetric method for the determination of traces of sulfide, based on its inhibitory effect on the oxidation of pyridoxal nicotinylhydrazone by potassium persulfate is described. The reaction is followed spectrofluorimetrically by measuring the rate of change of the fluorescence intensity (λex=365 nm, λ em=450 nm). The calibration graph (percentage inhibition vs. sulfide concentration) is Linear in the 10-80 ng S2- ml-1 range. The interferences of the method are described.View full abstractDownload PDF (829K) -
Yu KOMATSU, Yoshinori FUJIKI, Takayoshi SASAKI1984 Volume 33 Issue 5 Pages E159-E162
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIon-exchange properties of crystalline hydrous titanium dioxide fibers have been studied. Alkaline earth metal ions were adsorbed on the fibers from aqueous solutions. The distribution coefficient of the adsorption of alkaline earth metal ions of the fibers and the rate of the ion-exchange reaction were increased with increasing the temperature.View full abstractDownload PDF (481K) -
APPLICATION OF XANTHENE DERIVATIVES FOR ANALYTICAL CHEMISTRY. Part XXXIXShoko KITANO, Itsuo MORI, Yoshikazu FUJITA, Yoshiyuki KAMADA1984 Volume 33 Issue 5 Pages E163-E166
Published: May 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe rapid, simple, and sensitive spectrophotometric determination of Ge(IV) with ο-hydroxyhydroquinonephthalein(Qn.Ph.) in the presence of cetylpyridinium chloride(CPC) was studied in the con centration of 0 - 5.0 μg Ge(IV) / 10 ml. The Sandell sensitivity was 0.00042 μg cm-2 at 505 nm. The molar absorption coefficient of the complex was 1.7 × 105 dm3 mol-1 cm-1. The coexistence of Fe(III) could be tolerated up to about 400-fold excess over Ge(IV) without masking agents, and the interference of large amounts of various metal ions could be overcome by addition of EDTA or sodium fluoride solution.View full abstractDownload PDF (480K)
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