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Volume 43, Issue 7
Displaying 1-13 of 13 articles from this issue
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Masashi GOTO, Katumi AKABORI, Sayuri MAEDA1994 Volume 43 Issue 7 Pages 505-509
Published: July 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSFor the rapid analysis of medicinal drugs by bromometry and iodometry in the Japanese Pharmacopoeia method, a flow injection method with amperometric detection was developed. In the bromometry, a stream of bromate reagent composed of potassium bromate and potassium bromide is mixed with a stream of acid reagent, leading to bromine generation in the reaction tube. The bromine stream is mixed with a carrier stream injected sample, and the sample is oxidized by bromine in the reaction tube. The mixed stream is mixed with a stream of basic hexacyanoferrate(II) reagent, and the hexacyanoferrate(I II) ion is produced, while the unreacted bromine is reduced in the reaction tube. The concentration of sample is estimated by measuring the change of the reduction current based on the hexacyanoferrate(III) ion using an amperometric detector. In the iodometry, a similar procedure to that of the bromometry is perfomed using an iodate reagent instead of the bromate reagent. The component contents in isoniazid tablets, sodium thiosulfate injections, and ascorbic acid injections were analyzed by the proposed method and the Japanese Pharmacopoeia method. The analytical results compared well with each other. A throughput of as many as 30 samples per hour was reached in the proposed method.View full abstractDownload PDF (766K) -
Shigeru FUKUKAWA1994 Volume 43 Issue 7 Pages 511-515
Published: July 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSQualitative analysis of unsaturated polyester resins was performed by referring to the 13C-NMR chemical shifts of 27 kinds of standard linear unsaturated polyesters. The standard polyesters were synthesized from various kinds of dicarboxylic acids and glycols, and were purified with a preparative GPC apparatus. IR, 1H-NMR, and 13C-NMR (frequency 67.8 MHz) spectra of the standard polyesters with over 4 degrees of polymerization were measured and the 13C-NMR chemical shifts of the dicarboxylic acid and glycol components of each standard polyester were summarized. Components which are hard to distinguish by IR and/or 1H-NMR due to coexistence of more than 2 kinds of components can be determined by this method.View full abstractDownload PDF (492K) -
Keiji SAITO, Yoshiaki ISHIDA, Tokio OOSHIMA1994 Volume 43 Issue 7 Pages 517-524
Published: July 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA computer program for structural elucidation of organic compounds from their 13CNMR spectral data has been developed. Some empirical equations for calculating existence probabilities of certain substructures are presented. For the equations, sets of parameters for 554 pre-defined substructures have been determined from the spectral data of over 6100 compounds. About 93% of the substructures in 631 test compounds were predicted correctly. According, it seems that this method is applicable to the functional group analysis of various organic compounds.View full abstractDownload PDF (993K) -
Yuko YAMASHOJI, Manabu FUJIWARA, Takayuki MATSUSHITA, Minoru TANAKA1994 Volume 43 Issue 7 Pages 525-531
Published: July 05, 1994
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESS1H-NMR spectroscopy was used to investigate the chiral discrimination mechanism of cyclodextrins (mainly 2, 6-dimethylated β-cyclodextrin, DM-β-CyD) toward DL-alanine β-naphthylamide (DL-AN) in a mixture of D2O and various perdeuterated organic solvents such as acetone, acetonitrile (MeCN), dimethylformamide (DMF), dimethylsulfoxide (DMSO), dioxane, tetrahydrofuran (THF), methanol, ethanol, and 2-propanol. We have found that the chiral discrimination ability of the cyclodextrins toward the guest enantiomers can be evaluated from the splitting of their proton signals, especially that of the naphthyl a-proton, along with a large and lower magnetic field shift. In a D2O solution of DM-β-CyD and DL-AN, a signal splitting of each proton of DL-AN was not observed, although DM-β-CyD can interact strongly with DL-AN. However, the addition of each organic solvent to a D2O solution of DM-β-CyD and DL-AN has been found to enhance the chiral discrimination for the enantiomers, in spite of a lowered stability of their inclusion complex. The highest chiral discrimination was obtained in the mixed solvents containing 2030(v/v)% of organic solvents such as acetone, MeCN, DMF or DMSO. With dioxane and THF, the chiral discrimination was lower than that of the above organic solvents, possibly due to the strong interaction of DM-β-CyD with these solvents. On the other hand, with trimethylated-β-cyclodextrin (TM-β-CyD) which has no hydroxyl group, chiral discrimination could not be observed. These results indicate that the hydroxyl groups of CyDs may play an important part in chiral discrimination.View full abstractDownload PDF (882K) -
Fumio KUSANO, Susumu SATO, Namio HISAYASU, Makio UCHIYAMA1994 Volume 43 Issue 7 Pages 533-538
Published: July 05, 1994
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSTo determine trace amounts of selenium in calcium, a separating gathering method, in which selenium is distilled as the halogenide, was applied. A prescribed sample is added to phosphoric acid (15 w/v% ), hydroiodic acid (2.0 w/v% ) and metallic zinc solution (0.2 w/v% ) for distillation. The absorption collecting solution for selenium consisted of a mixed solution of perchloric acid-potassium permanganate-oxalic acid. By using the reduced gasification/ICP-AES method, a quantitative analytical method for trace amounts of selenium after prereduction of selenium(VI) to selenium(IV) in collecting solution was developed. The relative standard deviation (n=8) of selenium coexisting with 5000 μg cm-3 of calcium was 2.0%. The limit of detection was 0.05 ng cm -3. When this method was applied to determine trace amounts of selenium in calcium carbonate, highly accurate result (2±0.05 ng cm-3) were obtained.View full abstractDownload PDF (935K) -
Hiromu SATAKE, Yoshihiro SUGITA, Shoji KANESHINA, Sanae IKEDA1994 Volume 43 Issue 7 Pages 539-544
Published: July 05, 1994
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSA method for the determination of cysteine(CySH), penicillamine(PSH), aminoethanethiol (ASH) and dithiothreitol(DSH) was developed using nonsuppressed ion chromatography(IC) with UV detection (220 nm). Thiol compounds are converted to thiosulfate ion by the reaction with tetrathionate ion and the thiosulfate ion produced in reaction solution is quantitatively determined by nonsuppressed IC with 4 mM phosphate buffer (pH 7.5) as the eluent. Sample solution for IC was prepared by adding two equivalents of potassium tetrathionate to the respective thiol compound, and letting it stand for about 10 min, at 25°C for CySH and ASH, 50°C for PSH and 55°C for DSH. The calibration curves for thiol compounds were linear in the concentration range of 21100 μM. A relative standard deviation(%) of less than 1.5% was obtained at concentrations of 10100 μM thiol compounds. The detection limit for thiol compounds was 0.71μM. A 100-fold molar excess of amino acid and cystine, and an equimolar excess of penicillamine disulfide did not interfere.View full abstractDownload PDF (759K) -
Hiroyuki MATSUDA, Nobuo NAKANO, Toru ISHIJI, Kunio NAGASHIMA1994 Volume 43 Issue 7 Pages 545-549
Published: July 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA continuous monitoring system for 1, 1-dichloro-2, 2, 2-trifluoroethane (HCFC123: CHCl2CF3) has been developed using an electrochemical HCl sensor and a pyrolyzer consisting of a heater around a quartz tube. The decomposition efficiency of HCFC 123 into HCl was related to the heater temperature of the pyrolyzer (970990°C). At a constant temperature, the decomposition efficiency increased with the increase of residence time of the sample gas in the quartz tube. At a heater temperature of about 910°C and a 0.20 dm3 min-1 gas flow-rate, about 70% efficiency was obtained. The calibration curve was linear up to ca. 30 ppm and the detection limit was calculated to be about 0.1 ppm (signal to noise ratio=3.0) of HCFC123.View full abstractDownload PDF (775K) -
Wataru YOSHIMURA, Lù Xín Hóng, Atushi UZAWA1994 Volume 43 Issue 7 Pages 551-556
Published: July 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSIndium in some sediments was determined by means of coprecipitation and differential pulse anodic stripping voltammtrey. The analytical procedure was as follows. Fifty milliliters of distilled water is added to 10 ml of sample solution containing 0.04 g of sediment. Then, constant amounts of indium standard solution and 1 ml of zirconium oxychloride solution are added and the pH adjusted to 8.8 with ammonia water (1 : 2). The precipitate is separated by filtration and then dissolved in 25 ml of 4 M hydrochloric acid. After 1 ml of 5% KCNS solution is added, this solution is diluted to 50 ml with distilled water. A portion of this solution is employed for the determination of indium. After bubbling nitrogen gas through the sample solution for 100 s it was pre-electrolyzed for 100 s. The potential was scanned from -0.9 V to -0.3 V vs. SCE for dissolution of indium ion. Indium ion was determined from the peak current of the voltammogram. The results are as follows: (1) Zirconium hydroxide was the most effective collector of indium when the pH was adjusted to 8.8 with ammonia water (1 : 2). (2) Iron(III) and cadmium ions were found to interfere with the determination of indium. (3) The analytical procedure took about 90 min and 0.01 ppm of indium in sample solution could be determined. (4) This method is applicable to the determination of indium in river bottom and sea floor sediment.View full abstractDownload PDF (781K) -
Kiyoshi NAKAGAWA, Tadashi YONEMOTO, Aiko IWASA, Ikuko MATSUBARA1994 Volume 43 Issue 7 Pages 557-561
Published: July 05, 1994
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSA method was optimized to enhance the sensitivity of graphite furnace atomic absorption spectrometry for the determination of beryllium in biological materials. Magnesium nitrate was added to the acid-digested sample solution, and a low-noise photomultiplier was utilized. The amplifier was operated at 10 times the ordinary amplification. Best results were obtained with a magnesium concentration of 10-3 M when 50 μl of the solution was injected and ashed at 1250°C for 30 s. Under these conditions, the matrix alkali salts are diminished to such an extent that background correction can be readily made, without impairing the beryllium sensitivity. The detection limit is 0.005 ppb (Be 0.25 pg). By this method a beryllium content of 0.50 ng/g (SD 0.04, n=12) was found in NIST Bovine Liver (SMR 1577).View full abstractDownload PDF (798K) -
Setsuko KUDO, Daisuke SHINDO, Hideaki SUITO1994 Volume 43 Issue 7 Pages 563-567
Published: July 05, 1994
Released on J-STAGE: May 25, 2010
JOURNAL FREE ACCESSTransmission electron microscopy was applied to thin samples of fine particles of sphere-type Al2O3-SiO2 inclusion and platelet-type hematite (α-Fe2O3) sliced with an ultra-microtome. The compositions of local areas of the particles were obtained by EDX analysis. An iron sample containing sphere-type inclusions was prepared from 31 mass% CaO-16 mass%SiO2-53 mass%Al2O3 slag and Fe-0.96 mass%Si alloy at 1600°C. Also, the hematite containing 2.58 mass% Al2O3 was grown in a Na2O·2B2O3 flux. The two types of particles were separated from their matrix components, then fixated with acrylic resin, and finally sliced into thin plates of approx. 50 nm thickness. As a result, the inclusion particles were found to be composed of an Al2O3-SiO2 amorphous phase on the surface region and an Al2O3 single crystal phase in the inside region. The hematite particles were determined from their electron diffraction patterns to be single crystals with {0001} base planes. It was also confirmed that an Al2O3 phase was not deposited on the very outer surface of the hematite particles.View full abstractDownload PDF (4383K) -
Toshiko ITAGAKI, Mikio ISHIKURO, Kunio TAKADA1994 Volume 43 Issue 7 Pages 569-574
Published: July 05, 1994
Released on J-STAGE: January 15, 2010
JOURNAL FREE ACCESSTrace amounts of phosphorus in high purity chromium, nickel, copper and iron-chromium alloy were determined by molybdophosphate blue spectrophotometry after separation by beryllium hydroxide coprecipitation. The sample (1.0 g) was dissolved in perchloric acid and the solution was heated until fumes formed. After matrix elements were masked with EDTA, the phosphorus was precipitated as BeNH4PO4 with Be(OH)2 in ammonia solution at pH 9.7±0.2. Then, the precipitate was dissolved in nitric acids and perchloric acids mixture, finally, the phosphorus was colorimetrically determined with the Molybdenum Blue method. The recovery of phosphorus determined in high purity chromium by coprecipitation decreased with increasing pH of the solution on formation of Cr-EDTA complex. However, since chromium colud be completely masked under pH 2.7, phosphorus was quantitatively recovered. For the other metals, phosphorus was quantitatively recovered in the pH range from 1.5 to 5.0. The sample weight used in both present method and the JIS method for determination of phosphorus in iron and steel was 1.0 g. In JIS method, phosphorus in the sample were diluted to 1/10 and determined. However, in present method, all phosphorus in the sample were determined. Therefore, the limit of determination defined as the concentration equivalent to six times the standard deviation of the blank value was 0.46 μg/g, and the lower concentration of phosphorus could be determined.View full abstractDownload PDF (922K) -
Masayo YURURI, Hiroshi NAKANISHI, Kitaru TANIGUCHI1994 Volume 43 Issue 7 Pages 575-580
Published: July 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSA rapid and simple method using capillary electrophoresis was developed for the determination of ingredients in anti-cold preparations. Ten ingredients were divided into two groups, A and B. The A group contained both positively charged compounds in acidic media and neutral compounds; acetaminophen, anhydrous caffeine, guaifenesin, ethenzamide and potassium guaicolsulfanate. The B group contained negatively charged compounds in alkaline media; chlorpheniramine maleate, dextromethorphan hydrobromide, dihydrocodeine phosphate, dl-methylephedrine hydrochloride and noscapine. A 15 mM phosphate buffer, pH 11.0, containing 50 mM sodium dodecyl sulfate for the A group and 50 mM phosphate buffer, pH 3.0 for the B group were used as the carrier. On-column detection at 185 nm and hydrostatic injection for ten seconds were performed. Recoveries of the ingredients with the exception of anhydrous caffeine were 92.7109% and RSD were 0.56.3% (n=3). Recovery of anhydrous caffeine was 77.4110% and the RSD was 2.011% and the cause of disturbance was migration by methanol. Therefore, the proposed method could not be applied to the determination of anhydrous caffeine. Commercial preparations were analyzed by the proposed method. The contents of the ingredients without anhydrous caffeine were 94.0108%.View full abstractDownload PDF (853K) -
Kunihiko NAKATA1994 Volume 43 Issue 7 Pages 581-582
Published: July 05, 1994
Released on J-STAGE: May 29, 2009
JOURNAL FREE ACCESSDownload PDF (297K)
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