The Experts below are selected from a list of 12 Experts worldwide ranked by ideXlab platform
Tomohide Kitamura - One of the best experts on this subject based on the ideXlab platform.
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highly sensitive spectrophotometric determination of Cetylpyridinium Salt using a synergistic extraction effect in the presence of eosin and quinine
Bunseki Kagaku, 2003Co-Authors: Tadao Sakai, Tomohide KitamuraAbstract:塩化セチルピリジニウム（CPC）はエオシン（EOS）と1:2会合体を形成するが，検量線は原点を通らず，検量線の直線範囲は低濃度と高濃度領域で異なり，定量範囲が限定される．しかし，EOSと付加錯体を形成するキニーネ（QN）を共存させたイオン会合系に微量のCPCが加えられるとEOS-QN-CPC（1:1:1）三元イオン会合体が形成される．このイオン会合系においてはQN共存による相乗抽出効果が発現し，CPCの抽出性が高まるとともに検量線の直線範囲は拡大し，CPCに対しては2.5×10－7 M～1.5×10－6 Mの広い範囲で良好な直線関係が得られた．従来法の1:2会合体による検量線では1.0×10－6 M程度が定量限界であったが，本法では染料固有の大きなモル吸光係数は維持され，10－7 MオーダーのCPCの分析が可能となった．しかも酸性領域で形成される1:1会合体形成による定量法と比べ選択性もあり，実用分析として有用であることが明らかとなった．
Tadao Sakai - One of the best experts on this subject based on the ideXlab platform.
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highly sensitive spectrophotometric determination of Cetylpyridinium Salt using a synergistic extraction effect in the presence of eosin and quinine
Bunseki Kagaku, 2003Co-Authors: Tadao Sakai, Tomohide KitamuraAbstract:塩化セチルピリジニウム（CPC）はエオシン（EOS）と1:2会合体を形成するが，検量線は原点を通らず，検量線の直線範囲は低濃度と高濃度領域で異なり，定量範囲が限定される．しかし，EOSと付加錯体を形成するキニーネ（QN）を共存させたイオン会合系に微量のCPCが加えられるとEOS-QN-CPC（1:1:1）三元イオン会合体が形成される．このイオン会合系においてはQN共存による相乗抽出効果が発現し，CPCの抽出性が高まるとともに検量線の直線範囲は拡大し，CPCに対しては2.5×10－7 M～1.5×10－6 Mの広い範囲で良好な直線関係が得られた．従来法の1:2会合体による検量線では1.0×10－6 M程度が定量限界であったが，本法では染料固有の大きなモル吸光係数は維持され，10－7 MオーダーのCPCの分析が可能となった．しかも酸性領域で形成される1:1会合体形成による定量法と比べ選択性もあり，実用分析として有用であることが明らかとなった．
Saburo Hara - One of the best experts on this subject based on the ideXlab platform.
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sulfation of polysaccharides with sulfuric acid mediated by dicyclohexylcarbodiimide
Journal of Carbohydrate Chemistry, 1996Co-Authors: Ryo Takano, Shuichi Yoshikawa, Takashi Ueda, Kaeko Hayashi, Susumu Hirase, Saburo HaraAbstract:Abstract Starch, agarose, κ-carrageenan and porphyran were sulfated by sulfuric acid with dicyclohexylcarbodiimide as a condensation reagent. In all the cases, the sulfation at O-6 appeared to be predominant on the basis of results from methylation analyses. Although the reactivities of the other hydroxyl groups towards the present sulfation reaction were less than that at C-6, they varied depending on the position in the sugar residue of the polysaccharides. The sulfated agarose was further fractionated in terms of the difference in the solubility of its Cetylpyridinium Salt to KCl solution. The major fraction resembled the main polysaccharide of funoran (agarose 6-sulfate) on the basis of the behavior of its Cetylpyridinium Salt, 13C NMR measurements and methylation analyses.
Ryo Takano - One of the best experts on this subject based on the ideXlab platform.
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sulfation of polysaccharides with sulfuric acid mediated by dicyclohexylcarbodiimide
Journal of Carbohydrate Chemistry, 1996Co-Authors: Ryo Takano, Shuichi Yoshikawa, Takashi Ueda, Kaeko Hayashi, Susumu Hirase, Saburo HaraAbstract:Abstract Starch, agarose, κ-carrageenan and porphyran were sulfated by sulfuric acid with dicyclohexylcarbodiimide as a condensation reagent. In all the cases, the sulfation at O-6 appeared to be predominant on the basis of results from methylation analyses. Although the reactivities of the other hydroxyl groups towards the present sulfation reaction were less than that at C-6, they varied depending on the position in the sugar residue of the polysaccharides. The sulfated agarose was further fractionated in terms of the difference in the solubility of its Cetylpyridinium Salt to KCl solution. The major fraction resembled the main polysaccharide of funoran (agarose 6-sulfate) on the basis of the behavior of its Cetylpyridinium Salt, 13C NMR measurements and methylation analyses.
Shuichi Yoshikawa - One of the best experts on this subject based on the ideXlab platform.
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sulfation of polysaccharides with sulfuric acid mediated by dicyclohexylcarbodiimide
Journal of Carbohydrate Chemistry, 1996Co-Authors: Ryo Takano, Shuichi Yoshikawa, Takashi Ueda, Kaeko Hayashi, Susumu Hirase, Saburo HaraAbstract:Abstract Starch, agarose, κ-carrageenan and porphyran were sulfated by sulfuric acid with dicyclohexylcarbodiimide as a condensation reagent. In all the cases, the sulfation at O-6 appeared to be predominant on the basis of results from methylation analyses. Although the reactivities of the other hydroxyl groups towards the present sulfation reaction were less than that at C-6, they varied depending on the position in the sugar residue of the polysaccharides. The sulfated agarose was further fractionated in terms of the difference in the solubility of its Cetylpyridinium Salt to KCl solution. The major fraction resembled the main polysaccharide of funoran (agarose 6-sulfate) on the basis of the behavior of its Cetylpyridinium Salt, 13C NMR measurements and methylation analyses.