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Volume 33, Issue 11
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Tsutomu SHIBATA, Sakae HAMADA, Yuji OKUYAMA, Yoshitaka KASHIO1984 Volume 33 Issue 11 Pages 571-576
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIn the determination of carbon and sulfur in steels, a conventional spectrometric method gives either some what higher values than those obtained by chemical analysis or virtually unreliable values. This is due to the state of nonmetallic deposits such as carbides and sulfides, because selective discharge occurs between the deposits and a counter electrode. The selective discharge was able to be avoided by treating sample surfaces with a high energy pre-discharge prior to the determination of the elements by the conventional method with a low energy discharge. However, the high energy pre-discharge made emission intensities unstable for the determination, owing to the deformation of the tip of the electrode and the rise in temperature of the sample surface. For minimizing the deformation, the authors have examined in detail the combinations of circuit parameters (inductance, capacitance, and resistance) for the high energy pre-discharge. The best combination was that which made the discharge current oscillated slightly at the end of a discharge period. A newly developed spark stand, which is cooled with water and air, prevented completely the rise in temperature. The high energy pre-discharge so established was very effective for stabilizing the emission intensities, and the determination of the elements distributing ununiformly in steels has become possible.View full abstractDownload PDF (942K) -
Toshio ISHIZUKA, Yoshinori UWAMINO, Akira TSUGE1984 Volume 33 Issue 11 Pages 576-581
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSImpurities (18 elements) in silicon carbide powder samples were determined by inductively coupled plasma-emission spectrometry (ICP-ES). Sample solutions were obtained by either carbonate fusion or acid decomposition. In the carbonate fusion, silicon carbide (0.5 g) was fused with 2.5 g of sodium carbonate in a platinum crucible at 1000 °C for 30 min. In the acid decomposition, 0.5 g of silicon carbide was decomposed with 10 ml of hydrofluoric acid and 2 ml of nitric acid in a Teflon pressure vessel at 170 °C for 16 h. The matrix components from the carbonate fusion (about 1.1 % sodium ion and 4.5 % sulfuric acid in the sample solution) reduced the emission intensities by about 2025%. Thus, it was important to match the compositions of standard and sample solutions with regard to flux and acid. For the sample solutions obtained by the acid decomposition, the emission intensities were little affected by the matrix components (4 % hydrofluoric acid, 1.2 % nitric acid, and about 100300 μg/ml hexafluorosilicate). The detection limits for respective elements in the carbonate fusion method were higher than those in the acid decomposition method. The amounts of aluminum, boron, calcium, and chromium in silicon carbide obtained by the acid decomposition method were smaller than those obtained by the carbonate fusion method, presumably because these elements are incorporated into the silicon carbide lattice and the extraction of these elements by the acid decomposition method is incomplete. The measured values of other impurity elements agreed well between the two sample decomposition methods, indicating that these elements are segregated on the surface of silicon carbide powder particles.View full abstractDownload PDF (1129K) -
Hiroyuki TAKAGI, Toshimasa KIMURA, Hironobu KOBAYASHI, Kiyoshi IWASHIM ...1984 Volume 33 Issue 11 Pages 582-586
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA simple and rapid method has been developed for the determination of iodine in soil samples. Procedure: a 0.3 g sample is weighed into a polyethylene bag, and irradiated for five minutes in the TRIGA II reactor of Rikkyo University. After cooling a few minutes, the sample is transferred to a 30 ml nickle crusible. Iodine carrier solution containing a known amount of I-131 is added to the sample, which is then fused with a flux of 3 g KOH and 1 g KNO3. About 30 ml of water is added in several portions to the crusible, and heated. Both the solution and the residue are transferred to a 100 ml beaker. A few drops of sodiumhypochlorite solution is added. The content of the beaker is heated, and transferred to a 50 ml centrifugal tube. The supernatant separated by centrifugation is transferred to another 100 ml beaker. The solution is acidified with hydrochloric acid, heated, and cooled in a water bath. Sodium sulfite solution and palladium chloride solution are added, and the precipitate of palladium iodide is separated with a glassfiber filter paper. Gamma-rays from I-128 and I-131 in the precipitate are measured with a Ge(Li) detector coupled with a 4096 channel pulse height analyzer. Iodine contents of soils are calculated from the peak areas under the 443 keV gamma-ray of I-128. Corrections for chemical recovery are applied to them by means of the areas under the 365 keV gamma-ray of I-131. The present method was applied to a forest soil. The results were in good agreement with the results obtained by instrumental neutron activation analysis. The recovery of iodine in this procedure was about 80 %. Decontamination factors for Mn and Na throughout the procedure were 4 × 104 and 1 × 104, respectivery. The time required for the chemical procedure was about an hour, when four samples were subjected to a parallel analysis. The limit of determination was 0.03 μg iodine in a sample of 0.3 g.View full abstractDownload PDF (873K) -
Analytical method for natural dyes in foods IIIEiko AMAKAWA, Keiko HIRATA, Tsutomu OGIWARA, Kazuo OHNISHI1984 Volume 33 Issue 11 Pages 586-590
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA rapid and sensitive method for the determination of oil soluble natural dyes in foods was developed by using high performance liquid chromatography (HPLC) equipped with ODS column (Zorbax ODS), neutral silica gel column (Lichrosorb Si 60) and a UV detector. Analytical procedure is as follows. Food sample (5 g) was homogenized in a mixture of 25 ml of ethanolwater (1 : 1) and 2 ml of sesame oil, and the dyes were extracted with equal volume of ether. Samples rich in protein were subdivided and incubated for 1 h at 37 °C with 25 ml of 0.2 % protease (Pronase E) solution and 2 ml of sesame oil before the homogenization. Samples of oils and fats were mixed with 50 ml of hexane and extracted with 50 ml of ether-ethanol (3 : 1). After the addition of equal volume of hexane to the extracted solution, the mixture was shaken with 5 ml of 0.5 M ammonia solution and the aqueous phase was transferred into another separately funnel. (I ; Curcumin, Norbixin, Bixin) To the aqueous phase, 5 ml of 1 M acetic acid was added, and dyes were extracted with ether. (II ; β-Carotene) The organic phase was evaporated to dryness on a rotary evaporater and the residue was re-dissolved in hexane. (III ; Paprica extracts) A part of hexane solution from procedure (II) was applied onto an activated alumina column. After washing the column with 100 ml of hexane and 30 ml of hexane-acetone (30 : 1), dyes were eluted with 20 ml of acetone. The dyes obtained by the procedure (I) to (III) were separately determined by HPLC. The recoveries of dyes were not less than 70 %, and this method was successfully applied to the analysis of the commercial foods.View full abstractDownload PDF (742K) -
Tohru TAMURA, Masamitsu KATAOKA1984 Volume 33 Issue 11 Pages 591-596
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe construction of a perchlorate ion-selective electrode and its application to potentiometric titration of perchlorate ion in the explosives with Zephiramine was described. The PVC matrix membrane containing 7.7 (w/w)% of tris-(bathophenanthroline)iron (II) perchlorate ion-associate was used as an ion-sensing membrane. The disk membrane was affixed to a PVC tube (I.D. 7 mm) and silver-silver chloride electrode was used as the internal reference electrode. The composition of the cell including the present ion-selective electrode is as follows.
Ag-AgCl electrode/reference solution, 50 mM NaClO4 in 50 mM NaCl/PVC ion-exchange membrane//sample solution/SCE
The present ion-selective electrode exhibited a Nernstian response to perchlorate ion in the concentration range from 10-6 to 10-1 M. The potential of the electrode was constant over the pH range from 1 to 13. Selectivity coefficients were evaluated and the electrode exhibited a good selectivity with respect to most common anions, while it showed some interferences with respect to periodate, iodide, and thiocyanate ion. The present ion-selective electrode was successfully adopted to the potentiometric precipitation titration of perchlorate ion with Zephiramine. It was revealed that the presence of equal or excess amounts of nitrate ion in the sample solution lowered the potential break at the end-point. However, the interference can be eliminated by the reduction of nitrate ion by heating with acetic acid and zinc powder.View full abstractDownload PDF (953K) -
Shogo SUZUKI, Shoji HIRAI1984 Volume 33 Issue 11 Pages 596-600
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSConcentration of trace elements in an environmental reference material Mussel prepared by National Institute for Environmental Studies (NIES) has been determined by instrumental neutron activation analysis. The Mussel samples (ca. 50250 mg) were irradiated for 2 min (pneumatic transfer) at a thermal neutron flux of 1.5 × 1012 n cm-2s-1 and then for 5 h(central thimble)at thermal neutron flux of 3.2 × 1012 n cm-2 s-1 in Musashi Institute of Technology Research Reactor (MITRR). The gamma-ray measurements of 2 min irradiation samples were performed for 5 min intervals after 1 min cooling and for 427 min after 1280 min cooling using a Ge (Li) detector coupled to a 4096 channel multichannel analyzer. The gamma-ray spectra from 5 h irradiation samples were obtained by measuring samples for 314 h after 48 d cooling period and for 1445 h after 1550 d cooling. Peak-fitting procedure by a minicomputer system (GAMA system) was applied to analyze gamma-ray spectra. In this work 38 elements (Na, Mg, Al, S, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Mo, Ag, Cd, Sn, Sb, I, Cs, Ba, La, Ce, Sm, Eu, Tb, Hf, Ta, Au, Th, U) were quantitatively determined. Special cares were taken for obtaining accurate concentrations of aluminum and magnesium by correcting contributions by interefering nuclear reactions such as 31P(n, α) 28Al and 27Al(n, p)27Mg. Duplicate analyses showed a reasonable reproduciblity for the analytical data of major and trace elements, suggesting that the Mussel is homogeneous enough to be used as a certified reference material.View full abstractDownload PDF (799K) -
Eiko NAKAMURA, Hiroshi NAMIKI1984 Volume 33 Issue 11 Pages 600-603
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIon exchange technique is applied to remove the anionic surfactants (AS) which interfere the determination of cationic surfactants (CS). The sample solution is passed through a column of Amberlite IRA-401 (φ : 12 mm, 15 ml, Cl-type) at a flow rate of 1 ml/min. The column is washed with 50 ml of (1 : 1) mixture of methanol-water. By passing the sample through the column, the AS is adsorbed on the resin whereas most of the CS remains in the solution. Although the slight portion of the CS remains in the column, it can be completely eluted by washing with (1 : 1) methanol-water. The CS in the eluate is determined by Orange-II method according to JIS K 0102 (1981). The method is applied to artificial and sewage samples with the results better than 95 % recovery for 0.26.0 mg CS (calculated as Zephiramine) per liter.View full abstractDownload PDF (686K) -
Osamu FUJINO, Tadashi ATANO, Masahito SUGIYAMA, Masakazu MATSUI1984 Volume 33 Issue 11 Pages 604-608
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA pyrolytic-graphite-coated (PGC) carbon tube atomizer was made by passing PR gas (90 % Ar+ 10 %CH4) into a carbon tube, and heating the tube up to ca. 1600 °C for 5 min. The PGC carbon tube was used for determination of traces of europium in phosphate minerals (xenotime and monazite) by atomic absorption spectrometry. The lifetime of the carbon tube atomizer increased about four fold by this coating, although the peak absorbance for europium was not enhanced. Coexisting elements in the phosphate minerals scarcely interfered the determination. However, the direct determination of europium was difficult because of an interference from inorganic acids and the low europium contents in the phosphate minerals. Therefore, the concentration and separation of europium from interfering acids were needed. Phosphate samples (0.5 g) were dissolved in 30 ml of concentrated sulfuric acid by heating for about 3 h. Europium was determined after being extracted with 1 mol dm-3 di(2-ethylhexyl) phosphoric acid in cyclohexane at pH 2.0. Europium contents in the phosphate minerals as determined by the present method ranged from 2.7× 10-3 to 1.57 × 10-2 %. These values were in good agreement with those given by inductively coupled plasma atomic emission spectrometry and fluorometry.View full abstractDownload PDF (929K) -
Tsutomu FUKASAWA, Susumu KAWAKUBO, Tsuneo OKABE, Atsushi MIZUKIE1984 Volume 33 Issue 11 Pages 609-614
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA microscale technique for separating vanadium at ppb or sub-ppb level has been developed to be combined with flow injection spectrophotometry based on vanadium-catalyzed oxidation of gallic acid by bromate. The technique is effective in minimizing operational time and labor as well as quantities of samples. A 2.5 ml sample solution prepared in 0.02 M hydrochloric acid-0.1 % hydrogen peroxide is passed through an anion exchange microcolumn (Amberlite CG-400, 100 to 200 mesh, 1.7 mmφ × 45 mm) to adsorb vanadium. The column is washed with 0.5 ml of 0.02 M hydrochloric acid-0.1 % hydrogen peroxide followed by washing with 1 ml of 0.02 M hydrochloric acid to remove interfering cations and hydrogen peroxide. The adsorbed vanadium is eluted with 200 μl of 2 M hydrochloric acid, leaving molybdenum and tungsten in the column. The pH of the effluent is adjusted to 8 to 9 with aqueous ammonia and diluted to 250μl with water. A 100μl aliquot is injected into a flow of 0.25 M sodium bromate-0.03 M gallic acid (pH 3.8) for the catalytic spectrophotometric determination of vanadium at 380 nm. Vanadium (IV and V) ranging 0.1 to 5 ng in a sample solution is determined within about 40 min, with a variation coefficient less than 10 % at 2 ng. The tolerance limits of aluminum(III), iron (III), molybdenum (VI), and tungsten (VI) are 5, 100, 25, and 50 μg, respectively, which are 40 to 104 times as much as those without separation. The proposed technique was successfully applied to the analysis of rain water. The results from continuous monitoring of vanadium showed that the concentration of vanadium decreased with the elapse of time in raining.View full abstractDownload PDF (1065K) -
Hideharu SHINTANI, Kusuo TSUJI, Takuma OBA, Einosuke KOSHIMURA1984 Volume 33 Issue 11 Pages 614-617
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSMany medical devices such as flexible bags for blood preservation are made of polyvinyl chloride(PVC), which contains many plasticizers, e.g., di-2-ethylhexyl phthalate(DEHP). Recently the elution of DEHP and its hydrolyzed products, mono-2-ethylhexyl phthalate (MEHP), which is more toxic than DEHP, and phthalic acid(PA) from flexible bags into human blood for transfusion has become a social problem. So we studied on the conditions of the determination of these substances added in human serum and them in human plasma preserved in flexible bags, using high performance liquid chromatography(HPLC). We also studied on the pretreatment methods of serum and plasma for the determination of these substances. Analytical conditions were as follows. The HPLC conditions for the determination of PA in serum : column, Senshupak 5C18 (4.6 × 150 mm) ; temperature, ambient; mobile phase, phosphate buffer containing 5 mM monosodium phosphate-acetonitrile (80: 20), pH 2.8; flow rate, 0.8 ml/min; wavelength, 254 nm ; injection volume, 10 pi. For the determination of MEHP in serum : mobile phase, phosphate buffer containing 5 mM monosodium phosphate-acetonitrile (50 : 50), pH 2.8; the others were same as the above conditions. For the determination of DEHP in serum : mobile phase, wateracetonitrile (10 : 90); flow rate, 1.2 ml/min; the others were same as the above conditions. As the pretreatment for the determination of PA in serum, 1.0 ml of serum, 3.0 ml of water and 0.1 ml of 50 % phosphoric acid were mixed and ultrafiltrated by MPS-3. Then the ultrafiltrate was injected into HPLC. For the pretreatment for the determination of MEHP in serum, 1.0 ml of serum, 50μl of 50 % phosphoric acid and 3.0 ml of the mixed solution of ethylether-methanol (2 : 1) were mixed and kept one day at 4 °C. The mixture was stirred again and centrifuged. The supernatant was injected into HPLC. For the pretreatment for the determination of DEHP in serum, 1.0 ml of serum, 1.0 ml of 1 M sodium hydroxide solution and 3.0 ml of acetonitrile were mixed and centrifuged. The supernatant was injected into HPLC. The amounts of DEHP, MEHP, and PA in preserved human plasma were about 70, 6, and 3μg/ml, respectively. From the detection of MEHP, and PA besides DEHP in human plasma, it was speculated that a hydrolase played a role in the hydrolysis reaction.View full abstractDownload PDF (777K) -
Toru NOZAKI, Tomomi NAGANO1984 Volume 33 Issue 11 Pages 618-621
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIon flotation of twelve kinds of metal ions was investigated in the pH range of 1 to 12 with N-stearoyl-L-glutamic acid(SGA). A 20 ml of a solution containing (3.474.88) × 10-4 M of metal and 4.96 × 10-4 M of SGA was adjusted to the desired pH and was subjected to flotation in a cell (20 cm × 2.7 cm I. D.) for 1020 min with nitrogen bubbles. Recoveries of Co(II), Ni (II), Cu(II), Zn(II), and Pb(II) at pH 6 to 9, and of Fe(III), Al(III), Ga(III), Bi(III), and In(III) at pH 2.3 to 6.0 were 90100 % and 95400 % respectively. In(III), Al(III), Fe(III), Cu(II), Cd(II), and Ni(II) from Ga(III) at pH 9.4 to 10.6, In(III) from Co(II) and Ni(II) at pH 3.2 to 3.7, Fe(III) from Co(II), Ni(II), and Cd(II) at pH 2.9 to 3.6 were separated in 96100 % yield. The composition of the floated complexes was determined to have a metal/ reagent ratio of 1: 1 by the molar ratio method, which was supported by the mean number of proton released in the formation of the complexes. The stability constants of these complexes were also determined.View full abstractDownload PDF (551K) -
Hiroshi NISHIDA1984 Volume 33 Issue 11 Pages 622-624
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIn the presence of Zephiramine, beryllium(II) reacted with Chromazurol S (CAS, H4L) in the pH range 7.5 to 10.6 to form two kinds of 1 : 2 complexes with an absorption maximum at 525 nm and near 600 nm, respectively. In the spectrophotometric determination of beryllium by measuring the absorbance at 525 nm and pH 10, the calibration curve obeyed Beer's law for less than 1.3 × 10-5 mol dm-3 of beryllium. Therefore, more than 1.4 × 10-5 mol dm-3 of beryllium was not successfully determined. However, the wide concentration range of beryllium could be determined precisely by measuring the absorbance at the isosbestic point 561 nm. The optimum conditions for the determination of beryllium were as follows : pH =10, [CAS] =1.8 × 10-4 mol dm-3, [Zephiramine] =2.2 × 10-3 mol dm-3, [EDTA] = (14) × 10-3 mol dm-3, and the standing time>2 min. Beer's law was obeyed at 561 nm for (0.044.4) x 10-5 mol dm-3 beryllium. The apparent molar absorptivity at 561 nm was 3.51 × 104 dm3 mol-1 cm-1. The relative standard deviation for the determination of 0.04 ppm and 0.32 ppm beryllium was 0.5 % and 0.4 %, respectively. It was considered that the two kinds of 1 : 2 complexes with the individual absorption maximum at 525 nm and 600 nm were the mononuclear and the binuclear complexes, respectively.View full abstractDownload PDF (555K) -
Takahiro KUMAMARU, Fumio NAKATA, Shigeki HARA, Hiroshi MATSUO, Mitsuo ...1984 Volume 33 Issue 11 Pages 624-627
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA method for the determination of lead (II) by suction-flow hydride generation-heated quartz cell atomic absorption spectrometry using a continuous hydride generator equipped with a Teflon sampling suction cup was described. A 1-cm3 sample solution which was buffered with a pH 2.5 citrate solution was dropped into the suction cup and introduced by suction into streams of 0.8 mol dm-3 hydrochloric acid and 10 % hydrogen peroxide solutions. Then the solution was mixed with 7.5 % sodium borohydride solution in the reaction coil. The evolved hydride was swept into the electrically-heated quartz cell by an argon carrier gas and subsequently the atomic absorption of lead was measured. The peak height of spike-like signal for lead with 1-cm3 of sample solution was as high as about 50 % to that of broad signal obtained by conventional continuous sample introduction method with 1520 cm3 of the same solution. The linear calibration was obtained up to 250 ng Pb cm-3. The detection limit was estimated to be 2.7 ng Pb cm-3 and the relative standard deviation for 10 replicate measurements was 2.7 % for 100 ng Pb cm-3. More than 40 samples could be analyzed within one hour. This method was applied to the analysis of plant leaves standard reference materials.View full abstractDownload PDF (770K) -
Hiroshi NISHIDA, Taeko NISHIDA1984 Volume 33 Issue 11 Pages 627-629
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIron(III) formed a water soluble complex with 8-quinolinol in the presence of Triton X-100 and sodium thiosulfate at pH 4.4, showing two absorption maxima at 460 nm and 580 nm. Sodium thiosulfate was added as a masking agent of copper(II). Recommended procedure is as follows : Take a sample solution containing up to 500μg of iron(III) and adjust pH to 3.43.5 with 0.25 mol dm-3 sodium acetate solution. Add 0.2 cm3 of copper(II) sulfate solution(Cu 10 mg cm-3), 2 cm3 of Triton X-100 solution(0.12 g cm-3), 3 cm3 of 1 mol dm-3 sodium thiosulfate solution, and 2.0 cm3 of 8-quinolinol solution(8 mg cm-3). Copper sulfate solution was added to favor the formation of iron-8-quinolinolate complex. Adjust the pH to 4.4 with 0.25 mol dm-3 sodium acetate solution and dilute to 25.0 cm3 with water. After allowing to stand for 20 min, measure the absorbance at 460 nm or 580 nm against a reagent blank. Beer's law is valid over the range of 2200 ppm of iron(III). The apparent molar absorptivities at 460 and 580 nm are 5.17 × 103 and 3.91 × 103 dm3 mol-1 cm-1, respectively. Up to 10 mg of Cu(II), 4 mg of Cd(II), Mn(II), Pb(II), 1 mg of Cr(III), Mo(VI), 0.4 mg of Ni(II), 0.2 mg of Zn(II), Al(III), and 0.1 mg of Co(II), Ti(IV), and V(V) do not interfere. Interference of Cu(II) 10100 mg is removed by coprecipitation of iron(III) with manganese (IV) hydroxide from its ammoniacal solution containing hydrogen peroxide.View full abstractDownload PDF (476K) -
Akira NONAKA1984 Volume 33 Issue 11 Pages 630-631
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSGas-solid chromatography using steam pressurized up to 10 MPa at a column temperature of 350 °C was studied. The high pressure steam was generated continuously by pumping a constant flow of water into a heated precolumn. The carrier steam pressure was adjusted between atmospheric pressure and saturation pressure at the column temperature with a needle valve connected at the end of the separation column. The retention times of the samples (e.g., polyethylene glycols, higher carboxylic acids, etc.) decreased significantly as the pressure increased even with carrier steam having the same mass flow rate. For example, when the carrier steam pressure was raised from 6.5 MPa to 8.5 MPa at a column temperature of 340 °C (Psat =14.4 MPa), the retention times of the applied samples were shortened to fifth or sixth of the initial ones ; and tailing phenomena, if they existed, were reduced to a great extent.View full abstractDownload PDF (284K) -
Haruo HONMA, Hisako YANASHIMA, Mutsuko YOSHIDA, Keiko SUZUKI1984 Volume 33 Issue 11 Pages T113-T117
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIn differential thermal conductivity method for the detemination of carbon, hydrogen, and nitrogen, sublimable or volatile samples were lost in part during the weighing and purging, and this would result in the lower analytical values. To prevent this loss, a simple method was developed as follows. As a sampling device, a quartz capsule sealed with an indium foil was found to be most suitable. The cylindrical quartz capsule was 3 mm in diameter, 6 mm in depth, and ca. 200 mg in weight. Indium foil was 0.07 mm in thickness, 8 × 8 mm2 in area, and ca. 3.9 mg in weight. About 1500 μg of a sample was placed in the capsule and sealed tightly with the indium foil. The weight did not change for at least 12 h. The weighed capsule was inserted in the combustion tube and the subsequent procedures were carried out according to the conventional method. Although the blank values of this method were higher than those of the conventional platinum boat method, the standard deviation of blank values was sufficiently low. The variations of carbon, hydrogen, and nitrogen sensitivity factors were within the allowable ranges: ± 0.062, ± 3.58, and ± 0.30 μV/μg, respectively. Carbon, hydrogen, and nitrogen in naphthalene, cyclohexanone oxime, anisole, chlorobenzene, and nitrobenzene were successfully determined by this method. The total of the results for carbon and hydrogen, or for carbon, hydrogen, and nitrogen ranged 99.9100.1 % for naphthalene, anthracene, and azobenzene.View full abstractDownload PDF (758K) -
Osamu NARA, Masatoshi MIYAMOTO1984 Volume 33 Issue 11 Pages T118-T121
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe effective automatic stirring extractor presented previously for the rapid extraction of solid samples was applied to the assays of pharmaceutical tablets and vegetable drugs. The proposed extraction method was found to be superior to the methods authorized by JP X. In the assay of prednisolone tablets, the extraction chambers of 20 and 25 ml capacities were employed. The times taken to evacuate the chambers for 99.9 % were 20 and 25 min respectively. The results of the proposed method were the same as those of the authorized shaking extraction method. In the assay of capsicum extract, the results of extraction for 4 h were 16.39±0.21 % for the proposed method and 16.27±0.35 % for the authorized boiling extraction method with 95 % confidence limits. It was thus obvious that the application of the proposed method to those official methods simplified their extraction procedures by the elimination of the troublesome separation procedures required in those official methods. In the case of berberine extraction from coptis rhizome, the proposed method completed the extraction within only 2 h, whereas the authorized Soxhlet's method did not even in 24 h. The extraction flask with the calibration mark, with which the present extractor was equipped, was useful for dilution without transfer the extract to other volumetric flask.View full abstractDownload PDF (723K) -
Toshiyuki SHONO1984 Volume 33 Issue 11 Pages E449-E458
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSCrown ethers can selectively form complexes with alkali and alkaline earth metal ions, and sometimes other cations by ion-dipole interaction. Taking advantage of the cation binding selectivity, they have been widely used in analytical chemistry in the separation and the analyses of metal ions. In this review, general features of crown ethers and their analytical applications are described.View full abstractDownload PDF (1016K) -
Teruo HINOUE, Yutaka SHIMAHARA, Hideo MURATA, Yu YOKOYAMA1984 Volume 33 Issue 11 Pages E459-E466
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSWhen a light beam travelling through transparent solid is totally reflected from a solid-liquid interface, a part of the beam passes through a thin liquid region bordering on the solid phase. Photoacoustic wave induced in the liquid region at a glass-dye aqueous solution interface by absorption of an intermittent He-Ne laser beam was detected with a piezoelectric transducer. The photoacoustic signal intensity was proportional to a product of the dye concentration and the optical path. The present technique could be applied to observation of a concentration distribution profile of the dye in the solution layer of 200 to 800 nm from the interface at an interval of ca. 50 nm. Detection limit was 4.5×10-3 absorbance unit.View full abstractDownload PDF (962K) -
Satoshi KUSAKABE, Izumi SATOH, Tatsuya SEKINE1984 Volume 33 Issue 11 Pages E467-E472
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSSolvent extraction of magnesium(II), cobalt(II), and zinc(II) into toluene with benzoyltrifluoroacetone has been studied in the presence of various amounts of a cationic dye; methylene blue, crystal violet, or ethyl violet. Co-extraction of the ion-pairs of the ligand and dye which interferes with the spectrophotometry of the ternary complex by increasing the background absorption has also been studied. It was concluded that even when the metal extraction as ternary complex is effective enough, the spectrophotometry is not always possible because of a great background absorption by the ion-pairs of the ligand and dye.View full abstractDownload PDF (649K) -
DETERMINATION OF THALLIUM IN URINER. Raghunadha RAO, S. M KHOPKAR1984 Volume 33 Issue 11 Pages E473-E479
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA novel method for the solvent extraction separation of thallium(III) from associated elements is presented in this paper. Thallium(III) was quantitatively extracted at pH 4.0 from 0.1 M malonic acid with 0.08 M Amberlite LA-2 in xylene. Thallium was stripped from the organic phase with 1 M perchloric acid and was determined spectrophotometrically at 635 nm with malachite green. Thallium(III) was separated from zinc, cadmium, lead, iron, gallium and indium by process of selective extraction or selective stripping. It was possible to separate thallium (I) from thallium(III) in any proportion. It was also separated from the multicomponent mixture. The method was extended for the analysis of thallium in urine.View full abstractDownload PDF (758K) -
J.Rajagopala Rao, K.M. Parida, R.S. Thakur, S.B. Rao1984 Volume 33 Issue 11 Pages E481-E485
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA homogeneous precipitation method was developed for the estimation of molybdenum as its oxinate from pure solutions or in multicomponent systems. The method uses the slow release of molybdenum from its tartrate complex in the presence of oxine and simultaneous increase of pH by urea hydrolysis. A single step determination of molybdenum in the presence of 16 elements was achieved. EFTA was used to mask the metal ions.View full abstractDownload PDF (707K) -
Yoshimasa TAKAHASHI, Yoshikatsu MIYASHITA, Hidetsugu ABE, Shinichi SAS ...1984 Volume 33 Issue 11 Pages E487-E494
Published: November 05, 1984
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA new approach to the ordered multicategorical classification has been developed. The approach is based on the pattern recognition technique using simplex optimization. The ORMUCS method gives a single discriminant function for classification of the ordered multicategorical data. The ORMUCS method was compared with adaptive least square method (ALS method) in application to the classification problem of the ordered potency classes of antitumor mitomycin derivatives. In the full analysis and leave-one-out test, the ORMUCS method proved itself to be more stable than the ALS method for developing the discriminant function.View full abstractDownload PDF (857K) -
Ken SATO, Iwao IZUMI1984 Volume 33 Issue 11 Pages E495-E498
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA chemical method for isolating second phase constituents in aluminium and its alloys is described. The matrix is dissolved in boiling phenol and the second phase is obtained as an insoluble residue. The isolation is quantitative and without effect on composition for many intermetallic compounds which are commonly present in commercial aluminium materials.View full abstractDownload PDF (455K) -
AJAI K.SINGH, DINESH KUMAR, RAKESH K.RAWLLEY1984 Volume 33 Issue 11 Pages E499-E502
Published: November 05, 1984
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSCopper(II) has been spectrophotometrically determined after extraction of its 1-phenyl-4, 4, 6-trimethy1-1H, 4H-pyrimidine-2-thiol complex into isobutyl methyl ketone (MIBK). Extraction is maximum (94%) in the presence of 0.2-0.5 M NaOH in aqueous phase. Optimum concentration range for determination at λmax 400 nm is 2.5-10.2 ppm. The molar absorptivity and Sandell's sensitivity are 7×1031 mole-1cm-1 and 0.009 μg cm-2respectively. Interference of cations and anions found commonly associated with copper has been studied. Copper contents in the samples of human hair, goat liver, blood sera and alloys have been estimated.View full abstractDownload PDF (378K)
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