The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Kunitsugu Aramaki - One of the best experts on this subject based on the ideXlab platform.
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self Healing Mechanism of a protective film prepared on a ce no3 3 pretreated zinc electrode by modification with zn no3 2 and na3po4
Corrosion Science, 2003Co-Authors: Kunitsugu AramakiAbstract:Abstract Self-Healing Mechanism of a protective film against corrosion of zinc at scratches in an aerated 0.5 M NaCl solution was investigated by polarization measurements, X-ray photoelectron spectroscopy (XPS) and electron-probe microanalysis (EPMA). The film was prepared on a zinc electrode by treatment in a Ce(NO 3 ) 3 solution and addition of aqueous solutions containing 9.98 or 19.9 μg/cm 2 of Zn(NO 3 ) 2 · 6H 2 O and 55.2 μg/cm 2 of Na 3 PO 4 · 12H 2 O. After the coated electrode was scratched with a knife-edge crosswise and immersed in the NaCl solution for many hours, polarization measurements, observation of pit formation at the scratches, XPS and EPMA were carried out. This film was remarkably protective and self-Healing against zinc corrosion on the scratched electrode. The cathodic and anodic processes of zinc corrosion were markedly suppressed by coverage of the surface except for scratches with a thin Ce 2 O 3 layer containing a small amount of Ce 4+ and the surface of scratches with a layer composed of Zn 3 (PO 4 ) 2 · 4H 2 O, Zn(OH) 2 and ZnO mostly.
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xps and epma studies on self Healing Mechanism of a protective film composed of hydrated cerium iii oxide and sodium phosphate on zinc
Corrosion Science, 2003Co-Authors: Kunitsugu AramakiAbstract:Abstract A thin, protective film was prepared on a zinc electrode by coverage with a hydrated Ce2O3 layer and 0.0552 mg/cm2 of a Na3PO4 · 12H2O deposit layer and by drying the layers at 90 °C for 23 h, as has been reported in the preceding paper. This film was highly self-Healing at the scratched electrode in an aerated 0.5 M NaCl solution for many hours. The present investigation deals with elucidation on self-Healing Mechanism of this film by X-ray photoelectron spectroscopy and electron-probe microanalysis. The scratched surface was covered with deposits of Zn(OH)2, ZnO and small amount of Zn3(PO4)2. Both cathodic and anodic processes of zinc corrosion were markedly suppressed by coverage of the scratches with the deposits, resulting in the self-Healing activity at the scratched electrode in 0.5 M NaCl.
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self Healing Mechanism of an organosiloxane polymer film containing sodium silicate and cerium iii nitrate for corrosion of scratched zinc surface in 0 5 m nacl
Corrosion Science, 2002Co-Authors: Kunitsugu AramakiAbstract:A highly protective and self-Healing film of 1,2-bis(triethoxysilyl)ethane (C2H5O)3Si(CH2)2Si(OC2H5)3 polymer containing sodium silicate (water glass) Na2Si2O5 and cerium(III) nitrate Ce(NO3)3 was prepared on a zinc electrode previously treated in a Ce(NO3)3 solution. The film was examined by polarization measurement of the electrode in an aerated 0.5 M NaCl solution after the electrode was scratched and immersed in the solution for 4–72 h. Self-Healing Mechanism of the film was investigated by X-ray photoelectron spectroscopy and electron-probe microanalysis for the coated electrode surface after scratched and immersed in the NaCl solution. A passive film composed of Zn(OH)2, ZnSi2O5 and Ce3+–Si2O52− salt or complex was formed on the scratched surface and preferential deposition of Si2O52− compounds occurred at a defect of the passive film where Cl− accumulated, resulting in suppression of pitting corrosion at the scratch.
Y W Yang - One of the best experts on this subject based on the ideXlab platform.
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decoration of nitrogen vacancies by oxygen atoms in boron nitride nanotubes
Conference on Optoelectronic and Microelectronic Materials and Devices, 2010Co-Authors: Mladen Petravic, Robert Peter, Ivna Kavre, Ying Chen, Liangjen Fan, Y W YangAbstract:Decoration of nitrogen vacancies by oxygen atoms has been studied by near-edge x-ray absorption fine structure (NEXAFS) in several boron nitride (BN) structures, including bamboo-like and multi-walled BN nanotubes. Formation of nitrogen vacancies under low-energy ion bombardment reduces oxidation resistance of BN structures and promotes an efficient oxygen-Healing Mechanism, in full agreement with some recent theoretical predictions.
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decoration of nitrogen vacancies by oxygen atoms in boron nitride nanotubes
Physical Chemistry Chemical Physics, 2010Co-Authors: Mladen Petravic, Robert Peter, Ivna Kavre, Ying Chen, Liangjen Fan, Y W YangAbstract:Decoration of nitrogen vacancies by oxygen atoms has been studied by near-edge X-ray absorption fine structure (NEXAFS) around B K-edge in several boron nitride (BN) structures, including bamboo-like and multi-walled BN nanotubes. Breaking of B–N bonds and formation of nitrogen vacancies under low-energy ion bombardment reduces oxidation resistance of BN structures and promotes an efficient oxygen-Healing Mechanism, in full agreement with some recent theoretical predictions. The formation of mixed O–B–N and B–O bonds is clearly identified by well-resolved peaks in NEXAFS spectra of excited boron atoms.
Zhengwu Jiang - One of the best experts on this subject based on the ideXlab platform.
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Recent Advances in Intrinsic Self-Healing Cementitious Materials
Advanced Materials, 2018Co-Authors: Wenting Li, Zhengxian Yang, Biqin Dong, Haoxin Li, Jing Xu, Feng Xing, Qing Chen, Zhengwu JiangAbstract:Abstract Self‐Healing is a natural phenomenon whereby living organisms respond to damage. Recently, considerable research efforts have been invested in self‐Healing cementitious materials that are capable of restoring structural integrity and mechanical properties after being damaged. Inspired by nature, a variety of creative approaches are explored here based on the intrinsic or extrinsic Healing Mechanism. Research on new intrinsic self‐Healing cementitious materials with biomimetic features is on the forefront of material science, which provides a promising way to construct resilient and sustainable concrete infrastructures. Here, the current advances in the development of the intrinsic Healing cementitious materials are described, and a new definition of intrinsic self‐Healing discussed. The methods to assess the efficiency of different Healing Mechanisms are briefly summarized. The critical insights are emphasized to guide the future research on the development of new self‐Healing cementitious materials.
Mladen Petravic - One of the best experts on this subject based on the ideXlab platform.
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decoration of nitrogen vacancies by oxygen atoms in boron nitride nanotubes
Conference on Optoelectronic and Microelectronic Materials and Devices, 2010Co-Authors: Mladen Petravic, Robert Peter, Ivna Kavre, Ying Chen, Liangjen Fan, Y W YangAbstract:Decoration of nitrogen vacancies by oxygen atoms has been studied by near-edge x-ray absorption fine structure (NEXAFS) in several boron nitride (BN) structures, including bamboo-like and multi-walled BN nanotubes. Formation of nitrogen vacancies under low-energy ion bombardment reduces oxidation resistance of BN structures and promotes an efficient oxygen-Healing Mechanism, in full agreement with some recent theoretical predictions.
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decoration of nitrogen vacancies by oxygen atoms in boron nitride nanotubes
Physical Chemistry Chemical Physics, 2010Co-Authors: Mladen Petravic, Robert Peter, Ivna Kavre, Ying Chen, Liangjen Fan, Y W YangAbstract:Decoration of nitrogen vacancies by oxygen atoms has been studied by near-edge X-ray absorption fine structure (NEXAFS) around B K-edge in several boron nitride (BN) structures, including bamboo-like and multi-walled BN nanotubes. Breaking of B–N bonds and formation of nitrogen vacancies under low-energy ion bombardment reduces oxidation resistance of BN structures and promotes an efficient oxygen-Healing Mechanism, in full agreement with some recent theoretical predictions. The formation of mixed O–B–N and B–O bonds is clearly identified by well-resolved peaks in NEXAFS spectra of excited boron atoms.
Biqin Dong - One of the best experts on this subject based on the ideXlab platform.
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Recent Advances in Intrinsic Self-Healing Cementitious Materials
Advanced Materials, 2018Co-Authors: Wenting Li, Zhengxian Yang, Biqin Dong, Haoxin Li, Jing Xu, Feng Xing, Qing Chen, Zhengwu JiangAbstract:Abstract Self‐Healing is a natural phenomenon whereby living organisms respond to damage. Recently, considerable research efforts have been invested in self‐Healing cementitious materials that are capable of restoring structural integrity and mechanical properties after being damaged. Inspired by nature, a variety of creative approaches are explored here based on the intrinsic or extrinsic Healing Mechanism. Research on new intrinsic self‐Healing cementitious materials with biomimetic features is on the forefront of material science, which provides a promising way to construct resilient and sustainable concrete infrastructures. Here, the current advances in the development of the intrinsic Healing cementitious materials are described, and a new definition of intrinsic self‐Healing discussed. The methods to assess the efficiency of different Healing Mechanisms are briefly summarized. The critical insights are emphasized to guide the future research on the development of new self‐Healing cementitious materials.
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Smart releasing behavior of a chemical self-Healing microcapsule in the stimulated concrete pore solution
Cement and Concrete Composites, 2015Co-Authors: Biqin Dong, Guohao Fang, Yanshuai Wang, Feng Xing, Youyuan LuAbstract:A novel chemical self-Healing system based on microcapsule technology for cementitious composites is established. The key issue for such a system is how to release the Healing agent and how to activate the Healing Mechanism. The present study focuses on the release behavior. The smart release behavior of the Healing agent in the microcapsule is characterized by the EDTA (Ethylene Diamine Tetra-acetic Acid) titration method. The experimental results show that the release of the corrosion inhibitor covered with polystyrene resin (PS) is a function of time, and is controlled by the wall thickness of the microcapsule. Moreover, the pH value affects the release rate of the corrosion inhibitor; the release rate remarkably increases with the decreasing pH value.
