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Yoshio UMEZAWA
1991 Volume 7 Issue 4 Pages
525
Published: 1991
Released on J-STAGE: July 27, 2007
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Chuichi HIRAYAMA, Hirotaka IHARA
1991 Volume 7 Issue 4 Pages
527-536
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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Gel production methods have recently been improved, and a systematic search for packing materials has led to the creation of various hard particles from hydrophilic condensation polymers, making it possible for aqueous gel permeation chromatographic separation to occur at higher flow rates. In the present review, we explain the production methods, efficiency, and applications of hydrophilic packings developed due to this improvement in packing materials, while especially emphasizing their hardness.
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Tomokazu TANAKA, Kazukuni YONEMURA, Masakazu TANABE, Hiroshi KAWAGUCHI
1991 Volume 7 Issue 4 Pages
537-542
Published: August 10, 1991
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An electrostatically shielded water-cooled torch was constructed in order to minimize the "secondary discharge" at the sampling orifice, which has been a serious problem in the application of a water-cooled torch to inductively coupled plasma mass spectrometry. The outer gas flow rate could be reduced down to 5l/min with an appreciable increase of sensitivity. The intensities of copper ions originating from the sampling orifice decreased to the same level as that of the conventional torch, and doubly charged analyte ions considerably decreased, even compared to those with the conventional torch. A decrease in the plasma potential was also observed with a probe. These facts suggest that the secondary discharge at the sampling orifice was almost completely suppressed by the electrostatic shielding. An increase, however, in the ion signals of analyte oxide was observed. The intensities of ArO
+ and Ar
2+ decreased, but that of ArN
+ increased. The enhancement of ArN
+ may have resulted from an entrainment of air into the plasma with the decreasing outer gas flow rate.
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Hideaki MONJUSHIRO, Iwao WATANABE, Yu YOKOYAMA
1991 Volume 7 Issue 4 Pages
543-547
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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Ultraviolet photoelectron yield (UPY) spectra of gold evaporated on glass substrates were obtained in air. Photoelectron emission threshold energies
Et of the gold films were determined from the UPY spectra. The
Et values were greater for thinner films, indicating that the size of the deposited Au island is larger for thicker film. The size could be estimated from the
Et value. This method allows us to determine the Au film thickness of a few nanometers and the size of the small Au island without the need of high vacuum technology.
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Yoshihiro KUDO, Yasuyuki TAKEDA, Kazuhisa HIRATANI, Hiroaki MATSUDA
1991 Volume 7 Issue 4 Pages
549-553
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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Lithium and sodium ion transfers from water (w) to nitrobenzene (NB) phase containing Li
+-selective neutral carriers (L), three bis(8-quinolyloxy)propane derivatives and dibenzyl-14-crown-4 (DBz14C4), were studied by ion-transfer polarograph at 25°C. The logarithmic values of potentiometric selectivity coefficients were obtained by the relation log k
potLiNa=(F/2.3RT)(Δφ
oLi/LiL-Δφ
oNa/NaL), where Δφ
oMa/ML (M=Li and Na) denotes the formal potential of the process M
+(w-phase)+L(NB-phase)_ML
+(NB-phase). They were -2.1 for DBz14C4 and -1.
6-1.
2 for bis(8-quinolyloxy)propane derivatives. The stability constants (mol
-1 dm
3) of the 1:1 complexes for Li
+ and Na
+ in the NB-phase were also obtained from the metal ion-concentration dependence of the half-wave potentials. The Li
+ selectivity of each carrier L against Na
+ was discussed in terms of the values of Δφ
oo′Li/LiL and Δφ
oo′Na/NaL.
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Junichi ODO, Masaki MIFUNE, Akimasa IWADO, Tatsuya KARASUDANI, Hirotak ...
1991 Volume 7 Issue 4 Pages
555-559
Published: August 10, 1991
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Ion-exchange resins modified with some manganese(III)-porphyrins (Mn
3+-P
r) show a uricase-like catalytic activity, which is applicable to the determination of uric acid. The resonance Raman spectra of Mn
3+-P
r indicate that Mn
3+- porphyrins on modified resins are reduced to Mn
2+-porphyrins with oxidizing uric acid; Mn
2+-porphyrins then return to Mn
3+-porphyrins by oxidation with O
2 in the reaction system. It was concluded on the basis of these results that the modified resins show an uricase-like activity by repeating this redox cycle of manganese-porphyrins on the modified resins. Mn
3+-P
r exhibited no oxidative catalytic activity for 7-methylated derivatives of uric acid, indicating that the nitrogen atom at the 7-position of uric acid plays an important role in the activity of Mn
3+-P
r.
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Guo-Qing ZHANG, Masaaki KAI, Yosuke OHKURA
1991 Volume 7 Issue 4 Pages
561-565
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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A simple and sensitive method for assaying enkephalin-generating enzyme activity in rat brain tissues is described. Methionine-enkephalin, produced enzymatically from
α-endorphin and BAM-12P as substrates and leucine-enkephalin from
α-neoendorphin, were quantified by high performance liquid chromatography with postcolumn fluorescence derivatization using hydroxylamine, cobalt(II) and borate. The detection limits for methionine- and leucine-enkephalin- generating activities of the enzyme are 2.5 and 3.0pmol min
-1 mg-protein
-1, respectively. The enzyme can be characterized as an
endo-oligopeptidase A-like enzyme on the basis of inhibition studies.
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Yasuhiko NISHIKAWA
1991 Volume 7 Issue 4 Pages
567-572
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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A new double-stage separation method was developed for residue analysis using direct coupling of supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC). While conventional residue analysis requires much time and labor, this new method makes it possible to extract analytes selectively with a small amount of organic solvent and to introduce them into the chromatograph without injection. In this study, the extraction of pesticide residues from soil and various plant samples was investigated. In all cases, the pesticides were successfully extracted with supercritical carbon dioxide, especially with control of their separation from co-extracts in various ways, including adjustment of the modifier. For the soil samples, the extraction behavior of each pesticide from the matrix is discussed in terms of their electronic structures.
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Kazuichi HAYAKAWA, Ryuichi KITAMURA, Mizuka BUTOH, Noriko IMAIZUMI, Mo ...
1991 Volume 7 Issue 4 Pages
573-577
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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A high performance liquid chromatographic (HPLC) method with chemiluminescence (CL) detection was developed for the sensitive determination of 1, 3-diaminopyrene (1, 3-DAP), 1, 6-DAP, 1, 8-DAP and 1-aminopyrene (1-AP). The HPLC conditions were as follows: column, Cosmosil 5C18 (4.6mm i.d.×250mm); mobile phase, 10mM imidazole- perchloric acid buffer(pH 7.6)-acetonitrile (1:1, v/v); CL reagent, 0.02mM bis(2, 4, 6-trichlorophenyl)oxalate (TCPO) and 15mM hydrogen peroxide in acetonitrile. The oxidative degradation of DAPS and AP in the presence of metals was prevented by adding ascorbic acid to sample solutions. The calibration curves were straight over 2 orders of magnitude for all analytes, and their detection limits (as
S/
N was 3) were in the sub-fmol range. Dinitro- and nitropyrenes in sooty emissions of diesel- and gasoline-engine cars could be determined by this HPLC after reductive conversion into DAPs and AP, respectively, by refluxing the samples in the presence of sodium hydrosulfide.
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Takeshi GOMYO, Yasushi MORISHIMA, Shogo YAMAZAKI, Hiroshi DAIRIKI, Shi ...
1991 Volume 7 Issue 4 Pages
579-584
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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An analytical method for the total content of a fungicide, (
E)-4-chloro-α, α, α-trifluoro-
N-(1-imidazole-1-yl-2- propoxyethylidene)-
o-toluidine (triflumizole), and its metabolites in crops is described. Triflumizole and its metabolites having the 4-chloro-
α,
α,
α-trifluoro-
o-toluidine moiety in crops are converted to a derivative, 4-chloro-
α,
α,
α-trifluoro-o- toluidine, by hydrolyses in an acetate buffer solution, and then a sodium hydroxide solution; the derivative is cleaned by distillation, column chromatography and then determined by either high performance liquid chromatography or gas chromatography. The limit of detection was set at 0.02ppm. The recoveries ranged from 69 to 97%. Many kinds of crops sprayed with triflumizole were analyzed by both the individual analytical method for triflumizole and its main metabolite and the total analytical method; the amounts of residues were compared. When samples having a short preharvest interval were analyzed, the obtained residue values from both methods were almost the same. In order to establish the tolerances from the maximum residue value for each crop, analyses by the individual analytical method are considered to be sufficient.
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Hiroyuki KATAOKA, Nobuaki MUROI, Masami MAKITA
1991 Volume 7 Issue 4 Pages
585-588
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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A gas chromatographic method is described for the determination of linear alkylbenzenesulfonate (LAS). LAS was converted into its
N-methylanilide derivative by a convenient procedure involving ion-pair extraction followed by amidation, and was analyzed by electron-capture gas chromatography (ECD-GC) using 0.5% OV-17+0.1% FFAP on Uniport HP as the GC column packing. The derivative was very stable and provided excellent ECD response. By ECD-GC method, a linear calibration curve was obtained in the range of 5-1000ng of LAS. The detection limit of LAS was 0.1ng as injection amount. LAS in river water could be measured without influence of co-existing substances. The recoveries of LAS in river water were 95-109% and the reproducibility was found to be satisfactory. The LAS contents in river water samples were measured by ECD-GC method and Methylene Blue method, and the analytical results by both methods were compared.
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Minoru SAKAIRI, Alfred L. YERGEY
1991 Volume 7 Issue 4 Pages
589-592
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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Mass spectra of glycine, glycyl-glycine and glycyl-glycyl-glycine obtained by atmospheric pressure spray mass spectrometry (APS-MS) are compared with those obtained by electrospray mass spectrometry (ESP-MS). Intense cationized molecules of (M+Na)+ and (M+K)+ are observed in addition to protonated molecules of (M+H)+ in the atmospheric pressure spray mass spectra, while only protonated molecules are observed in the electrospray mass spectra. This result clearly indicates that the two methods differ greatly as regards ionization process, although sample solutions are sprayed to produce ions under atmospheric pressure in both methods.
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Yasushi TERUI, Kazuo YASUDA, Kichinosuke HIROKAWA
1991 Volume 7 Issue 4 Pages
593-597
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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The gas temperature of a graphite furnace was measured by a two line atomic absorption method using Pb lines. The correction factor of this method was calculated by assuming the gas temperature of the air-acetylene flame to be 2600K. The effective vapor temperature in the presence of a matrix modifier was higher than that in the absence of the modifier. One of the reasons is that the Pd matrix modifier delays the appearance time of the absorption signal to a higher temperature. The other is that the atoms or molecules of the modifier transfer energy to the analyte atoms, thus exciting them. This means that the gas phase is not in thermal equilibrium, and that the electron temperature had soared. It is thought that the temperature is somewhere different between the gas and electron temperatures.
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Yasushi TERUI, Kazuo YASUDA, Kichinosuke HIROKAWA
1991 Volume 7 Issue 4 Pages
599-604
Published: August 10, 1991
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The availability of several elements as a temperature indicator was studied. Suitable elements were Pd and Ni. Pb could be used only under the condition that Pb did not make an alloy with the matrix element. Sn was not useful because Sn in an alloy did work only in a very narrow dynamic range of temperature measurement. The correction factors of the experimental equations for each element were determined with air-acetylene and N
2O-acetylene flames. The factor obtained with the latter flame was found to be more accurate than that of the former. The effective vapor temperature in a graphite furnace was lower by several hundred degrees than the wall temperature when the factor obtained with the N
2O-acetylene flame was used. On the other hand, the factor obtained with the air-acetylene flame gave a vapor temperature in the furnace which was the same as that of the wall or slightly (200°C) lower than it.
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Edison MUNAF, Toyohide TAKEUCHI, Daido ISHII, Hiroki HARAGUCHI
1991 Volume 7 Issue 4 Pages
605-609
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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An automated system based on "continuous microflow analysis" and cold vapor atomic absorption spectrometry has been developed for monitoring the concentration of total mercury at sub-μg/l levels. The method involves a continuous microflow technique for sample digestion, reduction and extraction in small bore tubes (0.5mm i.d.) at μl/min flow rates of reagents. Sodium tetrahydroborate in sodium hydroxide solution was used as the reducing reagent. In the case of discrete injection of sample (200μl), analysis time for the determination of total mercury was about 3min per sample. The detection limit of mercury(II) was 0.15μg/l (
S/
N=3) for a gas flow cell of 40mm path length. The relative standard deviation was 0.99% at 4.0μgHg/l (
n=10). The calibration curve was linear up to 5.0μg/l. Under the optimal conditions, the present method could be successfully applied to the continuous monitoring of total mercury in waste water.
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C. GARCIA-OLALLA, L. C. ROBLES, A. J. ALLER
1991 Volume 7 Issue 4 Pages
611-615
Published: August 10, 1991
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The effects of various single and mixed metal chloride, sulfate, and nitrate upon the graphite furnace atomic absorption spectrometric determination of Se in aqueous solutions were studied. The results for some chlorides were compared with those for sulfate and nitrate. Among the metals studied (Pd, Hg, Cd, Ni, Cu, Mg, Ag) the best enhancement in the Se atomic absorption signal was obtained by the mixing pair Hg-Pd chloride.
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Eiji AOYAMA, Keiko AKAMATSU, Terumichi NAKAGAWA, Hisashi TANAKA
1991 Volume 7 Issue 4 Pages
617-621
Published: August 10, 1991
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A flow injection analysis system has been developed for the determination of very low concentrations (<1ng/ml) of selenium(IV). The system involves a micro column packed with a resin loaded with Bismuthiol-II sulfonate (Bis-IIS) for the on-line preconcentration of trace selenium(IV) and a manifold for the quantification of selenium based on the Se- catalyzed reduction of 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT). Selenium was selectively collected as selenotrisulfide (-S-Se-S-) on the resin by reaction with Bis-II S, and eluted with a small volume of penicillamine solution which withdraws the selenium from the resin. Selenium thus eluted as penicillamine selenotrisulfide was introduced to the flow injection analyzer, where penicillamine selenotrisulfide catalyzes the reduction of MTT to formazan by dithiothreitol. The interference from copper ion was eliminated by the adsorption of Cu on the resin as a bathocuproine disulfonate chelate. Reliability of the present method was confirmed from the determination of selenium contents in a biological standard sample.
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Abdulrahman A. ALWARTHAN, Ala'ddin ALMUAIBED, Alan TOWNSHEND
1991 Volume 7 Issue 4 Pages
623-625
Published: August 10, 1991
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A procedure is presented for determining titanium(IV) (10
-6-10
-2M) in a flow injection system using chemiluminescence detection resulting from the reaction of titanium(III) with a carbonate buffer after passage of the titanium(IV) samples through a Jones reductor minicolumn using 0.01M HCl as a carrier stream. The limit of detection is 1×10
-6M (52pmol per injection). The RSD at 4×10
-4M titanium is 4.4% (10 replicates). Some other ions (Ni(II), Co(II), Cd(II), Ce(IV) and Mo(VI)) were found to affect the titanium signal.
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Toshiki TAYA, Nobuko FUKUI, Kunio DOI, Makoto OTOMO
1991 Volume 7 Issue 4 Pages
627-632
Published: August 10, 1991
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The acid-base equilibria of Alizarin Red S(ARS) were investigated spectrophotometrically at 25 °C and μ=0.2 in the presence of
β-cyclodextrin (
β-CD). In the presence of
β-CD, the dissociation of the first proton (
β-OH) of ARS is slightly enhanced and that of the second one (
α-OH) is significantly suppressed. All the ionic species of ARS interact with
β-CD to form 1:1 associated complexes, the stabilities of which decrease in the order; HL-HA>H
2L-HA>L-HA> L-A, where L and A denote the fully deprotonated form of ARS and the deprotonated form of
β-CD, respectively. The distribution curves for all the species present in the ARS-
β-CD system are given as a function of the pH of the solution.
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Atsushi KATAYAMA, Tamio KAMIDATE, Miyuki MORITA, Hiroto WATANABE
1991 Volume 7 Issue 4 Pages
633-636
Published: August 10, 1991
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A novel spectrophotometric method was developed for the determination of aliphatic thiols. The method was based on the stoichiometric redox reaction between aliphatic thiol and a copper(II) complex with 1, 10-phenanthroline in dimethyl sulfoxide to form an intensely colored copper(I) complex, which had a molar absorptivity of 7000dm
3 mol
-1 cm
-1 at 444nm. The calibration curves for five aliphatic thiols of carbon numbers 1-8 had the same slope over the range from the detection limit of 5.0×10
-6 to 1.5×10
-4mol dm
-3. The relative standard deviation of five successive experiments was 2.0% at 8.6×10
-5mol dm
-3 of 1-butanethiol. The method was applied to the determination of methanethiol in gas samples.
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Isao SANEMASA, Ikuko KOGA, Toshio DEGUCHI
1991 Volume 7 Issue 4 Pages
641-643
Published: August 10, 1991
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Junichi GOTO, Gang SHAO, Miwa FUKASAWA, Toshio NAMBARA, Sotaro MIYANO
1991 Volume 7 Issue 4 Pages
645-647
Published: August 10, 1991
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Shuzo AKIYAMA, Kenichiro NAKASHIMA, Kyoko YAMADA, Nanako SHIRAKAWA, Ma ...
1991 Volume 7 Issue 4 Pages
649-651
Published: August 10, 1991
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Kazuya OHGA, Hiroki OYAMA, Yoshitaka MUTA
1991 Volume 7 Issue 4 Pages
653-656
Published: August 10, 1991
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Suwaru HOSHI, Norikazu NOTOYA, Masayuki UTO, Mutsuya MATSUBARA
1991 Volume 7 Issue 4 Pages
657-660
Published: August 10, 1991
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Shoichi KATSUTA, Hisanori IMURA, Nobuo SUZUKI
1991 Volume 7 Issue 4 Pages
661-663
Published: August 10, 1991
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Nobuhiro MARUBAYASHI, Yasuhiko ISHIDA, Mamoru HARATAKE
1991 Volume 7 Issue 4 Pages
665-668
Published: August 10, 1991
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Tadashi HATA, Youji FURUKAWA, Yoshihisa OZOE, Fumio MATSUMURA
1991 Volume 7 Issue 4 Pages
669-670
Published: August 10, 1991
Released on J-STAGE: June 30, 2006
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