The Experts below are selected from a list of 198 Experts worldwide ranked by ideXlab platform
Wei Pang - One of the best experts on this subject based on the ideXlab platform.
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pH measurements with ZnO based surface acoustic wave resonator
Electrochemistry Communications, 2011Co-Authors: Xiaotun Qiu, Rui Tang, Shih-jui Chen, Hao Zhang, Wei PangAbstract:Abstract This paper investigated pH measurements using ZnO based surface acoustic wave resonator (SAW). The resonant frequency of the SAW decreased as pH value changed from 7 to 2 (acid Region) or from 7 to 12 (Alkaline Region). The detection limits were 0.03 and 0.02 pH change, respectively, which were comparable to commercial pH meters. The interaction between hydronium (H3O+) or hydroxide (OH−) and ZnO was proposed to be responsible for the frequency drop. Both hydronium and hydroxide can increase the conductivity of the ZnO film, resulting in the resonant frequency decrease due to the acoustoelectric effect.
Shoji Motomizu - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of novel chitosan resin derivatized with serine moiety for the column collection/concentration of uranium and the determination of uranium by ICP-MS
Analytica Chimica Acta, 2003Co-Authors: Koji Oshita, Mitsuko Oshima, Yunhua Gao, Kyue-hyung Lee, Shoji MotomizuAbstract:Abstract A chitosan resin derivatized with serine moiety (serine-type chitosan) was newly developed by using the cross-linked chitosan as a base material. The adsorption behavior of trace amounts of metal ions on the serine-type chitosan resin was systematically examined by packing it in a mini-column, passing a metal solution through it and measuring metal ions in the effluent by ICP-MS. The resin could adsorb a number of metal cations at pH from neutral to Alkaline Region, and several oxoanionic metals at acidic pH Region by an anion exchange mechanism. Uranium and Cu could be adsorbed selectively at pH from acidic to Alkaline Region by a chelating mechanism; U could be adsorbed quantitatively even at pH 3–4. Uranium adsorbed on the resin was easily eluted with 1 M nitric acid: the preconcentration (5-, 10-, 50- and 100-fold) of U was possible. The column treatment method was used prior to the ICP-MS measurement of U in natural river, sea and tap waters; R.S.D. were 2.63, 1.13 and 1.37%, respectively. Uranium in tap water could be determined by 10-fold preconcentration: analytical result was 1.46±0.02 ppt. The resin also was applied to the recovery of U in sea water: the recovery tests for artificial and natural sea water were 97.1 and 93.0%, respectively.
Xiaotun Qiu - One of the best experts on this subject based on the ideXlab platform.
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PH measurements with ZvO based Surface Acoustic Wave Resonator
2011 16th International Solid-State Sensors Actuators and Microsystems Conference, 2011Co-Authors: Rui Tang, Xiaotun Qiu, Jie Zhu, Jonathon Oiler, Hai Huang, H. WangAbstract:This paper investigated pH measurements using ZnO based Surface Acoustic Wave Resonator (SAW). The resonant frequency of the SAW decreased as pH changed from 7 to 2 (acid Region) or from 7 to 12 (Alkaline Region). The detection limits were 0.03 and 0.02 pH change, respectively, which were comparable to commercial pH meters. The interaction between hydronium (H 3 O+) or hydroxide (OH−) and ZnO was proposed to be responsible for the frequency drop. Both hydronium and hydroxide can increase the conductivity of the ZnO film, resulting in the resonant frequency decrease due to the acoustoelectric effect.
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pH measurements with ZnO based surface acoustic wave resonator
Electrochemistry Communications, 2011Co-Authors: Xiaotun Qiu, Rui Tang, Shih-jui Chen, Hao Zhang, Wei PangAbstract:Abstract This paper investigated pH measurements using ZnO based surface acoustic wave resonator (SAW). The resonant frequency of the SAW decreased as pH value changed from 7 to 2 (acid Region) or from 7 to 12 (Alkaline Region). The detection limits were 0.03 and 0.02 pH change, respectively, which were comparable to commercial pH meters. The interaction between hydronium (H3O+) or hydroxide (OH−) and ZnO was proposed to be responsible for the frequency drop. Both hydronium and hydroxide can increase the conductivity of the ZnO film, resulting in the resonant frequency decrease due to the acoustoelectric effect.
Rui Tang - One of the best experts on this subject based on the ideXlab platform.
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PH measurements with ZvO based Surface Acoustic Wave Resonator
2011 16th International Solid-State Sensors Actuators and Microsystems Conference, 2011Co-Authors: Rui Tang, Xiaotun Qiu, Jie Zhu, Jonathon Oiler, Hai Huang, H. WangAbstract:This paper investigated pH measurements using ZnO based Surface Acoustic Wave Resonator (SAW). The resonant frequency of the SAW decreased as pH changed from 7 to 2 (acid Region) or from 7 to 12 (Alkaline Region). The detection limits were 0.03 and 0.02 pH change, respectively, which were comparable to commercial pH meters. The interaction between hydronium (H 3 O+) or hydroxide (OH−) and ZnO was proposed to be responsible for the frequency drop. Both hydronium and hydroxide can increase the conductivity of the ZnO film, resulting in the resonant frequency decrease due to the acoustoelectric effect.
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pH measurements with ZnO based surface acoustic wave resonator
Electrochemistry Communications, 2011Co-Authors: Xiaotun Qiu, Rui Tang, Shih-jui Chen, Hao Zhang, Wei PangAbstract:Abstract This paper investigated pH measurements using ZnO based surface acoustic wave resonator (SAW). The resonant frequency of the SAW decreased as pH value changed from 7 to 2 (acid Region) or from 7 to 12 (Alkaline Region). The detection limits were 0.03 and 0.02 pH change, respectively, which were comparable to commercial pH meters. The interaction between hydronium (H3O+) or hydroxide (OH−) and ZnO was proposed to be responsible for the frequency drop. Both hydronium and hydroxide can increase the conductivity of the ZnO film, resulting in the resonant frequency decrease due to the acoustoelectric effect.
Koji Oshita - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of novel chitosan resin derivatized with serine moiety for the column collection/concentration of uranium and the determination of uranium by ICP-MS
Analytica Chimica Acta, 2003Co-Authors: Koji Oshita, Mitsuko Oshima, Yunhua Gao, Kyue-hyung Lee, Shoji MotomizuAbstract:Abstract A chitosan resin derivatized with serine moiety (serine-type chitosan) was newly developed by using the cross-linked chitosan as a base material. The adsorption behavior of trace amounts of metal ions on the serine-type chitosan resin was systematically examined by packing it in a mini-column, passing a metal solution through it and measuring metal ions in the effluent by ICP-MS. The resin could adsorb a number of metal cations at pH from neutral to Alkaline Region, and several oxoanionic metals at acidic pH Region by an anion exchange mechanism. Uranium and Cu could be adsorbed selectively at pH from acidic to Alkaline Region by a chelating mechanism; U could be adsorbed quantitatively even at pH 3–4. Uranium adsorbed on the resin was easily eluted with 1 M nitric acid: the preconcentration (5-, 10-, 50- and 100-fold) of U was possible. The column treatment method was used prior to the ICP-MS measurement of U in natural river, sea and tap waters; R.S.D. were 2.63, 1.13 and 1.37%, respectively. Uranium in tap water could be determined by 10-fold preconcentration: analytical result was 1.46±0.02 ppt. The resin also was applied to the recovery of U in sea water: the recovery tests for artificial and natural sea water were 97.1 and 93.0%, respectively.
