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Volume 39, Issue 2
Displaying 1-13 of 13 articles from this issue
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Yoshihide TANAKA, Ayako OKAZAKI, Keisuke KITAMURA, Keiichiro HOZUMI1990 Volume 39 Issue 2 Pages 63-66
Published: February 05, 1990
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA sealed tube dry combustion method that is simple, accurate and precise for ultramicrodetermination of chlorine in organic compounds has been extended to determinations of bromine and iodine. A Pyrex glass tube having a length of ca. 18 cm and inner diameter of 6 mm was closed at one end and the sample was inserted into the tube. Oxygen gas was then introduced to replace air and the open end was closed forming a sharp tip. The tube was heated at 580°C in an electric furnace for 1 h. After cooling, the tip end of the tube was broken off in 10 ml of absorption liquid in a beaker so that the absorption liquid entered through the broken end raising the water level by 34 cm. In the case of bromine, a sodium nitrite solution (5 mg/10 ml) was used as the absorption liquid. After standing for 30 min, the inside wall of the tube was washed by a thin jet stream of water. In the case of iodine, 2% hydrazine hydrate was used as the absorption liquid. Since iodine adhered to the inside wall of the tube as fine crystals, it was hard to wash them out in the same manner as in the case of bromine. Therefore, the tube was held horizontally and gently rotated so that the iodine was reduced quantitatively to iodide in contact with the absorption liquid. The absorption liquid in the tube could be washed out by a jet stream of water. Both halogenides were titrated potentiometrically with 5×10-4 M silver nitrate standard solution. Analytical results obtained with several organic compounds containing bromine or iodine showed standard deviations of 0.17% and 0.25%, respectively.View full abstractDownload PDF (635K) -
Sadao MORI, Akira MORITA, Tetsuya KAWASHIMA, Hideki YANE1990 Volume 39 Issue 2 Pages 67-71
Published: February 05, 1990
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSSeveral techniques for compositional analysis of acrylonitrile-styrene copolymers have been compared. Copolymer samples of different composition have been prepared and then subjected to compositional analysis by proton-NMR, UV, IR and nitrogen (N) analysis. The styrene content in the copolymers obtained by NMR was consistent with that obtained by N analysis, but that obtained by UV (at 260 nm) was about 20% less than either of them obtained by NMR and N analysis. UV absorption coefficients at several absorption maxima (256.2, 259.9, 262.8, 265.0 and 269.6 nm) of the copolymers were calculated on the basis of composition obtained by N analysis or NMR. Hypochromic effects and hyposochromic shifts were observed at these wavelengths with the increase in the acrylonitrile component in the copolymers. The IR absorption coefficient of a nitrile characteristic band at 2240 cm-1 increased with increasing styrene content in the copolymers. A styrene characteristic band at 1600 cm-1 was not adequate for quantitative analysis because of its low absorption coefficient. In conclusion, UV and IR methods are not suitable for compositional analysis of the copolymers.View full abstractDownload PDF (713K) -
Toshihiko MIYAJI, Kiyokatu HIBI, Tadao SAKAI1990 Volume 39 Issue 2 Pages 73-77
Published: February 05, 1990
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSBivalent BPB anion reacts with 10-5 M quinine in neutral media to form a 1:2 charge transfer complex in 1, 2-dichloroethane, but not with 10-6 M benzalkonium. However, trace amounts of benzalkonium could be extracted into 1, 2-dichloroethane with BPB only when 10-410-5 M quinine was added in the extraction system giving a blue product. The molar absorptivity of the product was 50500 mol-1cm-1l at 610 nm. The blue product can be used for selective and rapid spectrophotometric determination of benzalkonium by the FIA method. The carrier solution (0.8 M phosphate buffer, pH 7.5) was pumped at a 0.75 ml/min flow rate and 1×10-4 M quinine standard solution and 5×10-5 M BPB were pumped at 0.25 ml/min each. Sample solutions (100 μl) were injected into the carrier stream by a six-way injection valve and mixed with the reagents in a 1 m reaction coil. The ion associate formed by quinine, BPB and benzalkonium was extracted into the organic phase in a 4 m extraction coil. The organic phase was separated by a phase separator with either a microporous polytetrafluoroethylene (PTFE) membrane (pore size 0.5 μm) or PTFE tubing (pore size 2 μm), and put through a 8-μl flow cell. Then the absorbance was measured at 610 nm and recorded as peak-shaped signals. Benzalkonium in the range of 5×10-6 M to 1.5×10-4 M could be determined and the relative standard deviation was 1.1% for 10 determinations of 1×10-4 M benzalkonium. The sample throughput was 24/h. The FIA method proposed here can be applied to the selective and rapid assay of benzalkonium in pharmaceuticals.View full abstractDownload PDF (708K) -
Tooru IMAHASHI, Yoshio YAMAUCHI, Muneo SAITO1990 Volume 39 Issue 2 Pages 79-85
Published: February 05, 1990
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSAdditives in PVC film were continuously extracted with supercritical carbon dioxide, and the extract was concentrated and trapped on a silica gel column placed immediately downstream of a back-pressure regulator where the pressure was at atmospheric pressure, while the pressure in the vessel was kept at 25 MPa. On completion of the extraction, the trapped components were eluted and separated on a silica gel column, having dimensions of 20 mm i.d.×200 mm length and placed after the trap column, by applying a pressure of 25 MPa. The column effluent was fractionated into five fractions with reference to a real-time three-dimensional chromatogram by a multi-wavelength photodiode array detector. Each fraction obtained was examined by IR and HPLC. The major component of the extract has been found to be di-2-ethylhexyl phthalate which was 83% of the total amount of collected fractions by weight. Other components were estimated to be saturated hydrocarbons, aromatic hydrocarbons and fatty acid esters.View full abstractDownload PDF (978K) -
Hiroshi NISHIDA1990 Volume 39 Issue 2 Pages 87-93
Published: February 05, 1990
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSIn beryllium(II)-Chromazurol S (CAS, H4L) complexes formed below pH 6, many points are yet unclear. Therefore, these complex formations were investigated by spectrophotometry. Beryllium(II) reacted with CAS in a stepwise manner a 1: 1 complex {Be(HL)-, absorption maximum: 570 nm} and a 1:2 complex {Be(HL)24-, absorption maximum: 600 nm} in an excess of CAS, and the 1:1 complex and a 2:1 complex (Be2L, absorption maximum: 568 nm) in an excess of beryllium(II). Hydroxo-complexes with their absorption maximum at 540 nm {Be(OH)(HL)2- and Be2(OH)2L2-} were formed from the 1:1 complex and the 2:1 complex with the increase of pH. However, the 1:2 hydroxo-complex was not formed. This is possibly due to the effect of the coordination number (4) of beryllium(II). The 1:1 complex and its hydroxocomplex formations were first confirmed in the present work. The 2:1 complex and its hydroxo-complex found in the present work have been reported previously as a 1:1 complex {Be(HL)-} and a 2:2 complex (Be2L24-), respectively. The complex formation constants were estimated to be K1= [Be(HL)-]/[Be2+] [HL3-]=(2.84±0.04)×104, K=[Be(HL)24-]/[Be(HL)-] [HL3-]=(3.92±0.08)×103, K3=[Be2L] [H+]/[Be2+] [Be(HL)-] =0.229±0.004, k1= [Be(OH)(HL)2-] [H+]/[Be(HL)-]=2.0×10-6, k2= [Be2(OH)2L2-] [H+]2/[Be2L]=5.0×10-12([SO42-]:0.050 mol dm-3, 25°C).From these results, the 1:2 complex was applied to the spectrophotometric determination of 0.040.4 ppm of beryllium(II) in 1.2×10-3 mol dm-3 CAS at pH 5.7. The apparent molar absorptivity at 600 nm was 4.0×104 dm3 mol-1 cm-1. The complex formations between beryllium(II) and CAS were also investigated in the presence of Zephiramine in the range of pH 3.9 to 5.5. The 1:1 complex and the 1:2 conplex were formed in a stepwise manner with the increase of pH.View full abstractDownload PDF (846K) -
Satoshi KURATANI, Yoshiaki ONOUE, Yasuharu NISIKAWA1990 Volume 39 Issue 2 Pages 95-101
Published: February 05, 1990
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA method to metalate of nickel and vanadyl to the octaethylporphyrin (OEP) and etioporphyrin I (Etio I) was examined. The metalation of porphyrin is usually performed in the liquid state ; that is, a DMF solution of porphyrin and metal chloride was refluxed. However, in this study the solid of the metal chloride was added to the DMF solution of OEP or Etio I, and immediately refluxed. This method was found to improve the rate of metalation and the product yield of metalloporphyrin. The complexes formed were identified by FAB (fast atom bombardment)/MS method, and AAS was used to determine the molar absorption coefficents of the metalloporphyrins. These matalloporphyrins were identified to be 1 : 1 complexes of porphyrins and metals. The absorption properties of porphyrins and their metal complexes were examined by measuring their absorption spectra. The absorption properties of the porphyrins depended upon the kind of porphyrin substituent, that is, the absorption properties are influenced by the electronegativity of the group. In addition, it was found that the ratio of α-band/β-band absorbance in the Q-band of metalloporphyrins related to the stability of the metal complexes.View full abstractDownload PDF (872K) -
Tomo TAKAOKA, Isao IKEUCHI, Tameyuki AMANO1990 Volume 39 Issue 2 Pages 103-108
Published: February 05, 1990
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA sample weighing 38 mg was decomposed by the oxygen flask combustion method and then chlorine and bromine were determined simultaneously by isotachophoresis. The combustion products were absorbed in to 10 ml of water containing 0.3 ml of 31 % hydrogen peroxide solution. After 30 min, 2 ml of 30 mM barium acetate was added to the absorber solution to eliminate the sulfate, and then the absorber solution was diluted to 50 ml with water. A 100 μl portion of the sample solution was introduced into the isotachophoretic apparatus (IP). Chloride and bromide ions were separated using 8 mM cadmium nitrate as the leading electrolyte and 10 mM citric acid as the terminating electrolyte. A sample weighing 34 mg was dissolved in 20 ml of water for determination of perchlorate anion. A 50 μl portion of the sample solution was introduced into IP. Perchlorate anion was separated using 5 mM sodium dithionate and 10 mM β-alanine as the leading electrolyte and 10 mM sodium acetate as the terminating electrolyte. A sample weighing 36 mg was dissolved in 50 ml of water for the determination of sodium and potassium. A 50 μl portion of the sample solution was introduced into IP. Sodium and potassium ions were separated by using a methanol/glycerol (8:2) solution containing 10 mM hydrochloric acid as the leading electrolyte and 10 mM tris(hydroxymethyl)aminomethane as the terminating electrolyte. The concentrations of Cl-, Br-, ClO4-, Na+ and K+ in the sample solutions were calculated from calibration curves. By the present methods, the standard deviations for the determination of chlorine, bromine, perchlorate anion, sodium and potassium were 0.20.5% and the mean analytical values respectively agreed with the calculated values. Isotachophoresis was shown to be effective for the separation of ions and elemental analysis.View full abstractDownload PDF (915K) -
Potentiometric FIA of acids and bases in nonaqueous solvents and its application to lubricating oilsAkiko KATAFUCHI, Toshihiko IMATO, Jun-ichi YAGI, Kozo TAKAHARA, Nobuhi ...1990 Volume 39 Issue 2 Pages 109-114
Published: February 05, 1990
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA new method for the FIA of acid and base samples in nonaqueous solvents was proposed. This analysis, using a "pH" buffer solution and a glass electrode, is based on the detection of pH changes in the buffer solution by the glass electrode when the sample acids or bases are mixed with the buffer solution. The sample (200 μl) injected into an ethanol stream was merged with the stream of the buffer solution (e.g. 5×10-3 M tetrabutylammonium butyrate-5×10-3 M butyric acid, M=mol dm-3) containing 0.1 M lithium chloride. The potential change of the glass electrode was observed as a peak-shaped signal, and a linear relationship between the peak height and the concentration of samples was observed. Many organic acids as well as aliphatic and some aromatic amines were determined by the proposed FIA titration of ca. 40 samples/h with less than 0.5% relative standard deviation. The sensitivity of the proposed method was discussed in connection with the relative acidities (apparent pKa's) of samples to those of the buffer acids. The proposed method was successfully applied to the determination of the total alkalinity in lubricating oils.View full abstractDownload PDF (883K) -
Fumiyo KUSU, Taeko TSUNETA, Kiyoko TAKAMURA1990 Volume 39 Issue 2 Pages 115-121
Published: February 05, 1990
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe fluorometric assay using 3-(p-hydroxyphenyl)-propionic acid (HPPA) was adapted for the determination of serum cholinesterase (ChE) activity in serum and plasma. The combined use of ChE and choline oxidase promotes the degradation of benzoylcholine to generate hydrogen peroxide. The resulting hydrogen peroxide can be determined fluorometrically through the reaction with HPPA in the presence of peroxidase. The detection limit of ChE activity was 10 IU/l. The relative standard deviation of the activity in serum was 1.7%. The present method provides an improvement in selectivity and sensitivity over the conventional methods. The present method was also applied to the determination of ChE activity in dried blood samples on filter paper with good results. From this fact, the method looks promising for practical use as a ChE mass screening test.View full abstractDownload PDF (1073K) -
Masahiko HANZAWA, Jun SAITO, Yukio YOKOYAMA, Masahiko TSUCHIYA1990 Volume 39 Issue 2 Pages 123-129
Published: February 05, 1990
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA method of analyzing new chemicals in fishes for the safety test was investigated using a liquid ionization (LI) mass spectrometer. The analyte used as one of the new chemicals was 2, 2', 4'-trimethyl-4-methoxydiphenylamine (TMMD). The LI method is applicable to analysis of a mixture without a complicated procedure for separating analytes from the matrix-like fish components. Two simple procedures for sample preparation were examined according to the concentration of TMMD added to carp. The procedures were as follows: The analyte TMMD with 3, 3'-dimethyldiphenylamine (DMD) as an internal standard was added to minced fish (30 g), then the analyte and the internal standard were extracted with 80 ml of acetonitrile in a homogenizer and the extract was filtered to remove insoluble materials. In the concentration range of 3.535 μg TMMD/g fish, 10 ml of the filtrate (total volume, 100 ml) was concentrated to 1 ml by evaporation. This was named the single extraction procedure. In the concentration range of 0.353.5 μg TMMD/g fish, 50 ml of the filtrate (total volume, 100 ml) was concentrated to 8 ml of aqueous solution. Two ml of ethylacetate was added to extract TMMD with DMD and the ethylacetate layer was concentrated to 0.5 ml. This was named the two step extraction procedure. The LI mass spectra exhibited protonated molecules (MH+) of TMMD and DMD as well as several peaks originating from the carps. The calibration curve calculated from the ratio of total MH+ ion of TMMD to that of DMD versus the concentration ratio is linear. The determination limit of TMMD in carp was about 0.3 μg. This result suggests that LI-MS is useful as a rapid method for the safety test.View full abstractDownload PDF (903K) -
Masaya AOYAGI, Yoshiaki YASUMASA, Akemi NISHIDA1990 Volume 39 Issue 2 Pages 131-133
Published: February 05, 1990
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSThe sample pretreatment method described is applicable for high sensitivity determination of total phosphorus and total nitrogen in 30% hydrogen peroxide solution, by means of FIA. The tolerable limit of hydrogen peroxide content in samples for the present FIA method to be applied is about 300 μg ml-1. Therfore, either diluting a sample or digesting hydrogen peroxide is inevitable. Heating a 10 ml of sample at 100°C for about 90 min with 0.2 g of platinum gauze added as catalyzer is shown to be a practically acceptable digestion procedure for 30% hydrogen peroxide solution containing phosphorus and nitrogen at the level of 100 ng ml-1 and 40 ng ml-1, respectively.View full abstractDownload PDF (418K) -
Toshihiko IMATO, Kazuya ISHII, Nobuhiko ISHIBASHI1990 Volume 39 Issue 2 Pages 135-138
Published: February 05, 1990
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA rapid and simple flow injection method for the determination of total water hardness using a cupric ion buffer and a flow-through type cupric ion selective electrode detector is proposed. The flow injection system was constructed with three stream channels. A sample solution of calcium or magnesium ion (200μl) was injected into a carrier (water) stream and was merged with a stream of 0.5 M sodium nitrate solution to maintain a constant ionic strength in the sample. This mixed stream was merged with the stream of cupric ion buffer solution consisting of 5×10-3 M cupric nitrate and 1×10-2 M EDTA adjusted to pH 9.4. The calcium or magnesium ion formed a complex with EDTA. In the reaction coil (0.5 mm i.d.×5.4 m) decreasing the concentration of EDTA in the buffer and as a result liberating the cupric ion from the EDTA-cupric ion complex. The change in the concentration of the free cupric ion was monitored with the cupric ion selective electrode and the concentration of the calcium or magnesium ion could be determined from the peak height of the electrode response. In order to make the sensitivity to the calcium ion equal to that to the magnesium ion, the pH of the cupric ion buffer was adjusted to pH 910 for determination of total water hardness. In this pH region, the amounts of EDTA reacted with the calcium and magnesium ions are almost the same and thus the change in the free cupric ion concentration is almost the same. A small amount of triethylenetetramine was added to the cupric ion buffer to suppress the effect of the chloride or bromide ion coexisting in the sample. The present method was successfully applied to determination of total water hardness in tap water with a sampling of 30 h-1 and a relative standard deviation of 0.7%. The results obtained by the proposed method were in good accordance with those obtained by the conventional chelate titration method.View full abstractDownload PDF (498K) -
Takashi KORENAGA, Yo YOKOTA, Kimiko OKADA, Teruo TAKAHASHI, Tosio MORI ...1990 Volume 39 Issue 2 Pages T29-T34
Published: February 05, 1990
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA simple and rapid method was established for the continuous determination of total sulfur oxide in exhaust gas. The FIA apparatus was composed of a double plangent micropump with short but fast reciprocations in order to optimize flowing and mixing properties. All the sulfur oxides in the exhaust gas were absorbed into hydrogen peroxide (1+9) solution according to the standard method based on JIS K 0103. A barium-Sulfonazo III complex solution was used as the coloration reagent for sulfate ion dissolved in the hydrogen peroxide (1+9) solution. The method was applied to the determination of total sulfur oxide in various industrial exhaust gases. The results obtained agreed with those obtained by the official titration method. The correlation equation was established as y=1.08x-0.8 and the correlation coefficient was 0.996. The method was found more sensitive, precise and reproducible than the official one, analyzing 30 samples/h. The detection limit and relative standard deviation of the method were 0.02 mg/l and 0.5% (at 5 mg/l) respectively. The FIA apparatus developed here could be applied with satisfactory results to the construction of a continuous monitoring system for SOx (ppm) in exhaust gas from the organic solvent waste incinerator of Okayama University. The present FIA system may also be applicable to the development of a high sensitivity atmospheric sulfur oxide monitoring system.View full abstractDownload PDF (905K)
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