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Yoshimasa NIHEI
1992 Volume 8 Issue 1 Pages
1-2
Published: 1992
Released on J-STAGE: July 27, 2007
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Shigeori TAKENAKA, Kunihiko DOHTSU, Makoto TAKAGI
1992 Volume 8 Issue 1 Pages
3-7
Published: February 10, 1992
Released on J-STAGE: June 30, 2006
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The trityl group of phosphoramidite reagents used on an automated DNA synthesizer was replaced with a hexadecyloxytrityl group. This reagent was used in the synthesis of
5′-hexadecyloxytrityl oligonucleotides by a standard procedure on a DNA synthesizer in good yield. The obtained oligonucleotides were smoothly detritylated under standard conditions. Reversed-phase high-performance liquid chromatography (HPLC) revealed that
5′-hexadecyloxytrityl oligonucleotides is retained remarkably, compared with 4, 4′-dimethoxy-tritylated (standard protecting group used on a DNA synthesizer) oligonucleotides of the same base-sequence. Since only the desired oligonucleotides carry the hexadecyloxytrityl group in crude reaction products obtained from a DNA synthesizer, they can be purified by HPLC under isocratic conditions, or under a simple stepwise elution of the desired oligonucleotides.
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Claudia KEUCHEL, Ludwig WELL, Reinhard NIESSNER
1992 Volume 8 Issue 1 Pages
9-12
Published: February 10, 1992
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A sensitive enzyme-linked Immunosorbent assay (ELISA) for the determination of the explosive 2, 4, 6-trinitrotoluene (TNT) and other nitroaromatic compounds was developed. As tracer, a trinitrophenyl-derivative conjugated to horseradish peroxidase was used. With this competitive assay, performed in polystyrene microtitre plates, TNT can be detected within the range of 0.02μg/l and 20μg/l. Cross-reactivities at the center points (50% values) of several nitroaromatic compounds were determined. Additionally, the cross-reactivities at different concentrations of the analytes were stated to yield a more realistic estimation of the interferences. Finally, the applicability of the immunoassay to the determination of TNT in water samples was assessed.
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Kyoji UENO, Atsushi MORIMOTO, Tsuneji UMEDA
1992 Volume 8 Issue 1 Pages
13-17
Published: February 10, 1992
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A column switching high-performance liquid chromatographic method with electrochemical detection was developed for the simultaneous determination of two modified steroidal antiandrogen anthrasteroids: 3aβ, 6-dimethyl- 2, 3, 3a, 4, 5, 8, 9, 10, 10aβ, 11, 11aβ, 11bα-dodecahydro-1
H-cyclopenta[α]anthracene-3, 8-dione (I) and its 3-hydroxy derivative (II) in human serum. After solid phase extraction from serum, the anthrasteroids were derivatized with 2, 5-dihydroxybenzohydrazide during the evaporation process of the reaction mixture at 20°C for 25min. The derivatives were detected electrochemically at +0.45V
vs. Ag/AgCl. The detection limits (
S/N=3) for compounds I and II in 0.5ml of human serum were 0.5 and 1ng ml
-1, respectively. Calibration curves for both compounds were linear over concentration ranges of 2-20ng ml
-1 and 20-200 ng ml
-1, respectively.
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José L. F. C. LIMA, M. Conceiçao B. S. M. MONTENEGRO, J. ...
1992 Volume 8 Issue 1 Pages
19-23
Published: February 10, 1992
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We constructed, tested and applied a tubular 5-ethyl-5-phenylbarbiturate ion-selective electrode based on tetraoctylammonium 5-ethyl-5-phenylbarbiturate dissolved in o-nitrophenyl octyl ether and immobilized on poly(vinyl chloride). The intrinsic features of the proposed electrode were assessed by using a low-dispersion single-channel flow injection analysis (FIA) system for performing repeated calibrations with sodium 5-ethyl-5-phenylbarbiturate standards, whose ionic strength was adjusted to 0.1M with 0.033M sodium sulfate. The determination of 5-ethyl-5-phenylbarbiturate in pharmaceutical preparations was accomplished by intercalating the proposed electrode into a two-channel FIA manifold. The results obtained were compared with those provided by the British Pharmacopoeia standard method.
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Kazuichi HAYAKAWA, Akio KATO, Atsushi YAMAMOTO, Motoichi MIYAZAKI
1992 Volume 8 Issue 1 Pages
25-29
Published: February 10, 1992
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In non-suppressed conductometric ion chromatography, when a carboxylic acid eluent of low pH is used, the signal intensity (Δ
Hc) is proportional to the sum of the conductivity change caused by changes in the sample concentration (Δ
Cs) as well as conductivity changes caused by changes in the eluent concentration (Δ
Ce). This can be expressed as Δ
HC=B(Δ
Cs)+B(Δ
Ce), where B is a constant. In this equation, Δ
Cs is constant for any sample species. However, Δ
Ce varies with changes in the sample capacity factors. This value is positive when the sample elutes before the system peak (
k′
s<
k′
e), and is negative when it elutes after the system peak (
k′
s>
k′
e). Therefore, the sample peak intensity (Δ
HC) is enhanced prior to the system peak and is suppressed after it. These effects increase the closer the sample and the system peaks. The effect of this theory was proved by a determination of orthophosphate using a TSK gel IC-Anion-PW column and a 0.75mM phthalic acid eluent. The detection limit of this method for orthophosphate (1×10
-11mol, with an S/N of three) was smaller (by a factor of 10-30) than those by previous conventional ion chromatographic methods. Also, the interference of chloride or nitrate, often observed in the previous methods, was removed by suppressing their peak intensities. When this method was applied for the determination of orthophosphate in environmental samples, other interfering compounds were effectively removed by a column-switching system attached to the ion chromatograph, and a trace level of the orthophosphate was determined.
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Masataka HIRAIDE, Tetsuji USAMI, Hiroshi KAWAGUCHI
1992 Volume 8 Issue 1 Pages
31-34
Published: February 10, 1992
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Nanogram quantities of cadmium in 100ml of water are quantitatively coprecipitated with indium hydroxide (100μg as indium) at pH 9.5. The precipitate is separated from the mother liquor by filtration with a 1-μm Nuclepore membrane filter and ultrasonically dissolved in 1M nitric acid. The cadmium in the final solution (1ml) is directly determined by graphite-furnace atomic absorption spectrometry without any serious background absorption due to indium. For the analysis of river water, coprecipitation is combined with sorption on a Sephadex A-25 anion exchanger for the separation of humic substances. The proposed method allows discrimination between negatively and positively charged cadmium species, with a detection limit as small as 2ngCd l
-1of water.
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Hayao SAKAMOTO, Takashi TOMIYASU, Norinobu YONEHARA
1992 Volume 8 Issue 1 Pages
35-39
Published: February 10, 1992
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A method has been proposed for the differential determination of mercury compounds in sediments, based on their successive extraction followed by a cold vapor atomic absorption spectrometric (CVAAS) determination. Organic mercury was first extracted by shaking a sediment sample with chloroform. The mercury in the extract was subsequently back-extracted into a 0.01M sodium thiosulfate solution. In order to separate mercury(II) oxide from mercury(II) sulfide, the residue was treated with 0.05M sulfuric acid so as to extract only mercury(II) oxide. Mercury(II) sulfide was finally extracted from the residue with 1M hydrochloric acid containing 3% sodium chloride in the presence of copper(I) chloride. The mercury in each extract was determined by CVAAS. When artificial standard sediment samples spiked with a given amount of each mercury compound were successively treated by the above-mentioned procedures, the recoveries of organic mercury, mercury(II) oxide and mercury(II) sulfide were 99.9, 99.5 and 98.2%, respectively. This method was successfully applied to a differential determination of mercury compounds in marine sediments.
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Yoshifumi AKAMA, Aijun TONG, Satoshi ISHIMA, Masatsugu KAJITANI
1992 Volume 8 Issue 1 Pages
41-44
Published: February 10, 1992
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A selective and sensitive atomic absorption spectrometric method is described for the determination of trace indium in metallic zinc. The sample was decomposed with HNO
3and the resulting solution was evaporated almost to dryness. The residue was dissolved in an HNO
3 solution (1+1) and diluted appropriately with water. After adjustment to pH 3.5, indium was extracted with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone in an MIBK (4-methyl-2-pentanone) solution. The amount of indium was measured by direct nebulization of the extract into an air/acetylene flame. The detection limit (
S/N=3) for indium in MIBK was 0.07μg/cm
3. The relative standard deviation (
n=5) was found to be 2.0% for 0.6μgIn/cm
3 in an MIBK solution. Indium extraction was not hampered by the presence of large amounts of zinc. The proposed method was confirmed to be successfully applicable to the determination of trace indium in metallic zinc.
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Ibrahim M. M. KENAWY
1992 Volume 8 Issue 1 Pages
45-50
Published: February 10, 1992
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The use of a cellulose-zinc hydroxide mixture for the micro determination of Cd(II), Cr(III), Cu(II), Fe(III), Hg(II), La(III), Ni(II), Pb(II), Sn(IV) and vanadate ion in a seawater sample at different pH was carried out employing ICP technique. The effects of concentration of Zn(II), mass of the cellulose, shaking time and the pH value of the sample on the preconcentration were studied. The method is simple and rapidly applicable for the microdetermination of ten heavy metals at ppb level. The effect of alkali and alkaline earth cations on the preconcentration of the tested metal ions was examined. The distribution coefficient K
d is in the range of 10
2.86-10
6.31cm
3 g
-1.
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Kunihiko NAKATA, Naofumi MORITA, Shigeo SAWADA, Masanosuke TAKAGI
1992 Volume 8 Issue 1 Pages
51-55
Published: February 10, 1992
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Although 2, 3- and 3, 4-endiol forms of diketogulono-δ-lactone (2, 3- or 3, 4-End.DKGL), which are formed from 2, 3-diketo-L-gulonic acid (DKG), showed an anodic wave on d.c. polarogram, the half-wave potentials of both 2, 3-End. DKGL and 3, 4-End.DKGL were slightly different from that of L-ascorbic acid (AsA). The anodic waves of both 2, 3- and 3, 4-End.DKGL had the characteristic of kinetic current, and their cyclic voltammograms in neutral aqueous buffer solutions showed anodic peaks, but no catholic peaks, probably due to the hydration of carbonyls of their oxidized forms. DKG showed two small anodic waves in neutral buffer solutions, the more positive h
1wave being an overlapping wave of the oxidation waves of 2, 3- and 3, 4-End.DKGL. The more negative h
2wave may be an oxidation wave due to the oxidation and weak adsorption of the enol form of DKG. The two anodic waves disappeared upon the addition of excess o-phenylenediamine; only one catholic wave due to the quinoxaline ring was newly obtained. The catholic wave may be used for the determination of DKG and 2, 3- and 3, 4-End.DKGL.
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Naoki OGURI, Akira ONISHI, Sigeki UCHINO, Keiji NAKAHASHI, Xigao JIN
1992 Volume 8 Issue 1 Pages
57-61
Published: February 10, 1992
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A Curie-point heating technique has already been introduced to pyrolysis-gas chromatography, which was developed by us. We analyzed the component of a multi-component polyester completely by using a combination of the technique and preparative HPLC. We used Curie-point pyrolysis-GC/MS, direct injection/MS, headspace-GC/MS and preparative HPLC for this study. We could thus determine the composition of the uncured polyester for manufacturing man-made marble consisting of an uncured polyester prepolymer, a crosslinking accelerator, an acrylate copolymer as the modification agent and some additives (surfactant and plasticizes). This analytical method is an available, convenient way for compositional analysis of complex polymers materials.
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Yuzuru SAKABE, Haruo OGURA
1992 Volume 8 Issue 1 Pages
63-66
Published: February 10, 1992
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The infrared (IR) spectra of isomers of dicyanobis(propylenediamine)chromium(III) chloride and related complexes have been measured over the range of 4000 to 290cm
-1 in order to determine the characteristic frequencies available for identification of the isomers. Our results suggest that the desired distinctive frequencies exist mainly in the C=N stretching band at 2145-2131cm
-1, the vibrations in the region 838-830cm
-1, the Cr-N stretching vibrations in the region 590-431cm
-1, and the Cr-C stretching or Cr-C≡N bending vibrations in the region 408-320cm
-1. These frequencies have enabled: 1) a distinction between
cis-(+)
589-[Cr(CN)
2(
d-pn)(
l-pn)]Cl and the diastereoisomeric isomers, such as
cis-(-)
589-[Cr(CN)
2(
d-pn)
2]Cl or
cis-(+)
589-[Cr(CN)
2(
l-pn)
2]Cl (pn=propylenediamine=1, 2-diaminopropane); 2) the identification of the geometric isomers of Λ-
cis-(-)
589-[Cr(CN)
2(
d-pn)
2]Cl which results from differences in the relative position of the methyl groups of propylenediamine ligands, and 3) the discrimination of ethylenediamine complexes from that of propylenediamine. In these paramagnetic Cr(III) complexes, the measurement of NMR spectra is made worthless due to the influence of the large magnetic moment of unpaired electrons. Accordingly, the importance of the structural information obtained by IR measurements is very high in their identification.
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Yoshiaki SASAKI, Shoji TAGASHIRA, Yoshiko MURAKAMI, Makoto YOSHIDA, Ke ...
1992 Volume 8 Issue 1 Pages
67-70
Published: February 10, 1992
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A number-average molecular weight measurement was tested as a direct and simple method for the confirmation of polymerization of the metal complex in organic solvent. This method was applied to the complexes of thallium(I), lead(II) and nickel(II) with
O, O′-dialkyl dithiophosphates (alkyl groups=methyl, ethyl, propyl and butyl) in benzene, chloroform and acetonitrile. In the cases of lead(II) and nickel(II) complexes, the number-average molecular weight in any solvent did not depend on the concentration of these complexes, while it agreed with the molecular weight of each monomer of these complexes. On the other hand, the magnitude of the number-average molecular weight for thallium(I) complexes increased with increasing the concentration of the complex but did not go up to beyond twice the molecular weight of monomer in any solvent. The dimerization constants of thallium(I) complexes were obtained by analyzing the relationship between the number-average molecular weight and the concentration of the complex. The values of dimerization constants were little affected by the alkyl group in the ligand. But the values were affected by solvents and became smaller in the order: chloroform, benzene and acetonitrile.
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Mohammed El-Sayed METWALLY, Fathalla F. BELAL
1992 Volume 8 Issue 1 Pages
71-75
Published: February 10, 1992
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A sensitive and rapid colorimetric method was developed for the determination of nitrite in natural water samples. The method is based on coupling primaquine phosphate (PP) with diazotized
p-nitroaniline (PNA) or with diazotized
p-aminobenzophenone (PABP) in acid medium. The orange color produced with both amines was stable for more than 24h, and has an absorption maximum at 484nm, and 482 for PNA and PABP, respectively. The calibration graph was linear in the concentration range of 0.025-1.25ppm of nitrite, with a minimum detection limit of 0.015ppm. The molar absorptivities were 8×10
4mol
-1 cm
-1 and 7.11×10
4mol
-1 cm
-1 for PNA and PABP, respectively. Heavy metals common to natural waters did not interfere. The interference from reducing anions such as I
-, S
2-, SO
32-, and S
2O
32- was eliminated by precipitation as insoluble lead salts. The excess lead ions did not interfere. Because PP is less liable to self-diazotization-coupling reaction compared with
N-(1-naphthyl)ethylenediamine (BMR), the method could be adopted for automated flow-injection analysis of nitrite. In addition, the coupling agent used is safe; a promising substitute for the so-long used Bratton-Marshal reagent which was reported to be carcinogenic. The proposed method is very sensitive and selective.
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Ms. Manjusha A. KARVE, Shripad M. KHOPKAR
1992 Volume 8 Issue 1 Pages
77-80
Published: February 10, 1992
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A novel method is proposed for the solvent extraction separation of indium from associated elements. Indium can be quantitatively extracted in the pH range of 3.5-5.5 with 0.1mol dm
-3Aliquat 336S in xylene from 1×10
-2mol dm
-3 ascorbic acid solution. It was stripped with 1mol dm
-3nitric acid and was determined directly using an atomic absorption spectrophotometer at 303.9nm. An excellent separation of indium from aluminum, gallium and thallium was possible. It was also separated from iron, copper, nickel and lead present with it in alloys, as well as minerals. The method was reproducible with a standard deviation of ±0.44%.
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Highly Sensitive Detection of Surface Molecules
Teiichiro OGAWA, To-oru YASUDA, Hirofumi KAWAZUMI
1992 Volume 8 Issue 1 Pages
81-82
Published: 1992
Released on J-STAGE: July 27, 2007
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Mizuo MAEDA, Yoshiharu MITSUHASHI, Koji NAKANO, Makoto TAKAGI
1992 Volume 8 Issue 1 Pages
83-84
Published: 1992
Released on J-STAGE: July 27, 2007
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Akira OHKI, Kiyoshi KAWAMOTO, Kensuke NAKA, Shigeru MAEDA
1992 Volume 8 Issue 1 Pages
85-86
Published: 1992
Released on J-STAGE: July 27, 2007
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Seiki YAMAGUCHI, Shogo OZAWA, Tokuji IKEDA, Mitsugi SENDA
1992 Volume 8 Issue 1 Pages
87-88
Published: 1992
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Takashi MASADOME, Shin-ichi WAKIDA, Yuji KAWABATA, Toshihiko IMATO, No ...
1992 Volume 8 Issue 1 Pages
89-91
Published: 1992
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Hideji TANAKA, Eiko YAMAMOTO, Hideyoshi MORITA, Shigeru SHIMOMURA
1992 Volume 8 Issue 1 Pages
93-95
Published: February 10, 1992
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Tsutomu KATSURA, Fuki KATO, Kazuko MATSUMOTO
1992 Volume 8 Issue 1 Pages
97-98
Published: February 10, 1992
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Shoji IMAI, Toshiyuki TANAKA, Kengo SAITO, Yasuhisa HAYASHI
1992 Volume 8 Issue 1 Pages
99-101
Published: February 10, 1992
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Suwaru HOSHI, Sachiko KANAGAMI, Masayuki UTO, Mutsuya MATSUBARA
1992 Volume 8 Issue 1 Pages
103-106
Published: February 10, 1992
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Hidehiko FUJII, Mitsuhiro HASHIMOTO, Shin NAKAMURA
1992 Volume 8 Issue 1 Pages
107-110
Published: February 10, 1992
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Kazuichi HAYAKAWA, Kyoko NOMURA, Motoichi MIYAZAKI
1992 Volume 8 Issue 1 Pages
111-113
Published: February 10, 1992
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Nobuya NAGASHIMA, Chiaki SANO, Tetsuya KAWAKITA, Yoichi IITAKA
1992 Volume 8 Issue 1 Pages
115-117
Published: February 10, 1992
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Nobuya NAGASHIMA, Chiaki SANO, Tetsuya KAWAKITA, Yoichi IITAKA
1992 Volume 8 Issue 1 Pages
119-121
Published: February 10, 1992
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