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Volume 46, Issue 8
Displaying 1-11 of 11 articles from this issue
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Development and characteristics of the chiral stationary phases consist of polysaccharide derivatives and application to large-scale separationAkito ICHIDA1997 Volume 46 Issue 8 Pages 613-625
Published: August 05, 1997
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe importance of optically active compounds for pharmaceutical use has increased. The high-performance liquid chromatographic resolution on chiral stationary phases is useful for large-scale preparation of optically active compounds and estimations of their separating costs as well as determination of optical purity. Chiral stationary phases consisting of polysaccharide derivatives were developed by adsorbing them onto silica gel based on the findings obtained from cellulose triacetate. The characteristics of cellulosic carbamates (OC, OF, OG, OD) and amylosic carbamates (AS, AD) as well as cellulosic esters (OA, OB, OJ, OK) in chiral recognition are considered here along with resolved compounds.: Optimization of the separating conditions was performed while considering differences among acidic, neutral and basic analytes. Furthermore, we introduced the principle and applications on the Simulated Moving Bed process to produce optically active compounds on the industrial scale.View full abstractDownload PDF (2617K) -
Hiroshi ANDO, Shinichi MORISAWA, Keiichiro HOZUMI1997 Volume 46 Issue 8 Pages 627-632
Published: August 05, 1997
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA carbon, hydrogen and nitrogen microanalyzer equipped with a self-integrated measuring system features the transportation of a combustion gas into a cylindrical pump having a reproducible inner volume and the collection of three signals of water, carbon dioxide and nitrogen when the pump slowly pushes out the gas towards a series of three differential thermal-conductivity cells. However, these signal intensities are not directly proportional to the true concentration of the respective components in the pump, because of the coexistence of foreign components other than the object. A correction of the signal intensity is therefore needed to obtain accurate analytical results. The conventional correction method gave rise to a minute analytical error, since the calculation involved a process to roughly estimate the quantities of the three elements in the sample being analyzed. An algebraic modification on simultaneous equations representing quantities of the three elements has resulted in the discovery of new formulae of simultaneous equations by which precisely corrected analytical results can be directly calculated, thus eliminating the need for a rough estimation of the quantities of the elements.View full abstractDownload PDF (1179K) -
Naohito YOSHIKAWA1997 Volume 46 Issue 8 Pages 633-638
Published: August 05, 1997
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSIn Japan salt-making factories produce salt from the brine obtained by concentrating sea water through an ion-exchange membrane electrodialyzer. Determining the composition of the brine plays an important role in the operation of the electrodialyzer. I tried to use ion-exchange electrodes for determining the brine composition. However, it was impossible to do this directly without such a means as the addition of ionic-strength adjustors, because the electrode potential was affected by the ionic-strength of the brine. On the basis of these experimental results, I developed a method for determining the brine composition without diluting the brine and adding ionic strength adjustors. This new method corrects measurements of the target ion electrode potential by using the chloride electrode potential, which has a linear relationship to the ionic strength of the brine, thus making it possible to determine the brine composition by using calcium, potassium, divalent-cation and chloride electrodes.View full abstractDownload PDF (1201K) -
Kazuko YAMAMOTO, Akira YONETANI, Toshihiro SHIRASAKI, Kazuo YASUDA1997 Volume 46 Issue 8 Pages 639-643
Published: August 05, 1997
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA chemical modifier was studied to analyze Sb in natural water samples using graphite-furnace AAS. It was found that Ag is a good chemical modifier for the determination of Sb, because, Sb formed intermetallic compounds with Ag, and its activity coefficient decreased depending upon the increasing atomic percent of Sb. Sb was captured in the intermetallic compound until it almost reached the melting point of Ag. The recovery of Sb was kept within 90110%, even if coexisting ions were changed. It was found that the analyzed value by this method for National Research Council Canada SLRS-3 showed good coincidence with the certified value. Also, the analytical results were in good agreement with those of a microwave-induced plasma-mass spectrometry(MIP-MS) in a natural-water measurement.View full abstractDownload PDF (970K) -
Kunihiro WATANABE, Yuichi TERADA, Masayuki ITAGAKI1997 Volume 46 Issue 8 Pages 645-651
Published: August 05, 1997
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA separation method has been developed which uses a separator (filter-paper phase separator) with filter paper that can separate the aqueous phase from a mixture of two liquids under high-speed stirring. The apparatus, equipped with a filter-paper phase separator, was available for longer than 6 hours. The aqueous phase in extraction vessel A in the presence of chloroform was transported into vessel B by a chemical pump after separating the aqueous phase. Simultaneously, the aqueous phase was returned to the vessel A. As a result, pseudo three-phase equilibrium was obtained among organic phase 1, the aqueous phase and organic phase 2. Zinc(II) and cadmium(II) were added to extraction vessel A. PAN [1-(2-Pyridylazo)-2-naphthol] and BzA [Benzoylacetone] were dissolved in the organic phase (vessel A and B), as extraction reagents, respectively. After 120 minutes of extraction under high-speed stirring, zinc(II) was extracted above 99% into the BzA-chloroform phase (vessel A), and was not extracted into the PAN-chloroform phase. On the other hand, cadmium(II) was not extracted into the BzA-chloroform phase. Zinc(II) and cadmium(II) could be separated over the range of 0 1000μg, respectively.View full abstractDownload PDF (1405K) -
Koichi YAMAMOTO, Kyoko SAKUNO1997 Volume 46 Issue 8 Pages 653-659
Published: August 05, 1997
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA titration method for the determination of ionic surfactants with chromazurol S (CAS) as an indicator was examined. A trivalent dye anion, HCAS3-, reacts with a cation (C+), such as a quaternary ammonium salt containing a long-chain alkyl group, to form an ion associate, (C+)2·H2 CAS2-, causing a color change from orange to purple. An anionic-surfactant (AS) solution at pH 5.7 is titrated with a cationic titrant, tetradecyl-dimethylbenzylammonium chloride (Zeph-Cl), until the formation of a 1: 1 ion associate, Zeph+·AS-, of AS with Zeph-Cl. This is followed by the formation of a 2: 1 ion associate, (Zeph+)2-H2CAS2-, of H2CAS2- with the excess Zeph-Cl, which causes a color change from orange to purple. A cationic surfactant (CS) solution at pH 5.7 is titrated with an anionic titrant, sodium lauryl sulfate (Na-LS), until CS forms a 1: 1 ion associate, CS+·LS- rather than a 2: 1 ion associate, (CS+)2·H2CAS2-, to cause a color change from purple to orange. AS at concentrations from 10-5 to 10-4 mol dm-3 and CS at concentrations from 10-5 to 4 × 10-4 mol dm-3 could be determined by the proposed method. This method was applied to the determination of anionic surfactants in commercial detergents. The results were in good agreement with those of the JIS titration method (Epton method).View full abstractDownload PDF (1323K) -
Ikuko ISHII-KARAKASA, Hitoo IWASE, Kyoko HOTTA1997 Volume 46 Issue 8 Pages 661-664
Published: August 05, 1997
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe standard sugars (GalNAc, Galβ1-3GalNAc) in the core region of O-linked oligo-saccharides were labeled with a fluorescent reagent, 2-aminopyridine, by reductive amination. These sugars were then analyzed by 1H-NMR spectroscopy. The chemical shifts and spectral pattern of the structural-reporter groups of the pyridylaminated sugars agreed with that of the structural-reporter groups of the corresponding O-linked sugar-alditols, except for the H-2 and the N-acetyl protons of N-acetylgalactosamine. It was proven that the structural-reporter groups of the O-linked sugar-alditols are applicable to a structural analysis of the corresponding pyridylaminated sugars. The structures of GalNAc-PA and Galβl-3GalNAc-PA, prepared from fetuin in fetal calf serum, were analyzed using this method.View full abstractDownload PDF (679K) -
Yoshikazu NAKAMOTO, Toshio TOMIYAMA1997 Volume 46 Issue 8 Pages 665-668
Published: August 05, 1997
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIt is important to determine trace amounts of antimony and selenium in crude oil, since they are known to be catalyst poisons in the refinery processes. The decomposition of crude oil by an oxygen-bomb combustion method was studied in order to determine antimony and selenium by ICP-MS. By a decomposition procedure, organic antimonious and selenious compounds were completely converted into the corresponding inorganic species, which were absorbed by a 0.01 M nitric acid and 1% hydrogen peroxide solution. The detection limit of the proposed method was 1 ng g -1 for both elements. This method was applied to the determination of trace amounts of antimony and selenium in various crude oils.View full abstractDownload PDF (942K) -
Eiko NAKAMURA, Masayuki WATANABE, Hiroshi NAMIKI1997 Volume 46 Issue 8 Pages 669-675
Published: August 05, 1997
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSA non-boiling evaporation method has been studied for the preconcentration of trace metals in highly purified water. A sample (50100 cm3) was taken to a polycarbonate Erlenmeyer flask (250 cm3), and then placed into a water-ethylene glycol (1:1) bath (120°C). While the temperature of the sample was maintained at about 95°C, the vapor in the flask was led to a receiver in an ice bath by passing through air circulated with an air pump for condensation. About 2 hours were required for evaporation to dryness of a 100 cm3 sample solution. After evaporation, 0.5 g of water or HNO3 (0.3 M) was added to dissolve the residue. The metals in the solution were then analyzed by a flameless AAS. Sodium, potassium, magnesium and zinc in highly purified water were found to be determined at a level of 12 ng/dm3 by the proposed method.View full abstractDownload PDF (1271K) -
Shigeki MATSUTA, Teiji TAKAGAWA, Kenichi SHIBATA1997 Volume 46 Issue 8 Pages 677-682
Published: August 05, 1997
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSFilms formed on the surface of lithium metal which had been immersed in organic solutions were analyzed using FT-IR. We developed a new measurement method based on FT-IR for investigating reactive compounds. It is called the “KBr covered method”. Using this method, we measured films formed on the lithium metal as well as reactive powder compounds. Lithium metal and solution {methyl acetate (MA), ethyl acetate (EA), dimethyl carbonate (DMC), diethyl carbonate (DEC)} were kept at 60°C for 11 days in button cells. In MA and DMC, films were formed on lithium metals. However, in EA and DEC, the lithium metal changed into a powder. The main reaction products were as follows: lithium acetate in MA; lithium ethylate and lithium ethylacetoacetate in EA; Li2CO3 in DMC; and Li2CO3, lithium ethylate and lithium ethyl carbonate in DEC. We suggest that the reaction scheme on lithium metal in EA is a two-molecule reaction, and that the other solutions' reactions on lithium metal are single-molecule reactions.View full abstractDownload PDF (975K) -
Yuka MORINO, Shinya YAMAMOTO, Katsumi ISHIWATA, Tasuku TAKAMATSU1997 Volume 46 Issue 8 Pages 683-688
Published: August 05, 1997
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe identification of an eluate from ion-suppression HPLC using a water/methanol mobile phase containing trifluoroacetic acid was investigated using the pinpoint (PP) concentration and a microscopic reflection FT-IR measurement. Sodium-5-benzoyl-4-hydroxy-2-methoxybenzensulfonate was chosen as the standard, since it has been formulated in many cosmetic products at a fairly low level as a UV absorber. The absorbance of the background spectrum, mainly due to a trifluoroacetic acid residue, could be minimized by using a centrifugal vacuum concentrator with a polypropylene tube for fractionation. An evaluation of the identification limit of the obtained spectrum was carried out using a commercially available IR spectra retrieval system with an attached spectra database and a custom-made database comprising of spectra obtained by the PP concentration; also the degree of agreement between the database and the sample spectra, were used as an index of the identification limit. By spectral retrieval using a range of wave-numbers from 2000 to 700 cm-1, the identification limit was found to be 500 ng for the HPLC eluent of the standard and 2μg for that of the cosmetic lotions when retrieved against the PP-standard spectra.View full abstractDownload PDF (1207K)
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