The Experts below are selected from a list of 156 Experts worldwide ranked by ideXlab platform
Chi Sun Poon - One of the best experts on this subject based on the ideXlab platform.
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effects of sodium Calcium Cation exchange on the mechanical properties of Calcium silicate hydrate c s h
Construction and Building Materials, 2020Co-Authors: Yohannes Lim Yaphary, Florence Sanchez, Chi Sun PoonAbstract:Abstract Calcium silicate hydrate layer (C-S-Hlayer) is considered to be the fundamental building block of hydrated cement. The effect of sodium ions on the atomic scale mechanical properties of C-S-Hlayer remains, however, unclear. Yet, this information is critical for understanding and predicting the macroscopic performance of concrete structures during their service life. Herein, the intrinsic mechanical properties of C-S-Hlayer with sodium-exchange ions replacing some Calcium Cations were studied by molecular dynamics simulations. The interatomic interactions provided insights into the role of Na+ within the atomistic scale of C-S-Hlayer. It was found that Na+ did not significantly alter the mechanical properties (i.e., strength and stiffness) of C-S-Hlayer. The larger Cationic attraction on the interlayer water molecules seen in the presence of Na+ occurred due to the exchange of two Na+ for one Calcium Cation and resulted in a volume expansion of C-S-Hlayer while a stiffening of its interlayer.
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Effects of sodium/Calcium Cation exchange on the mechanical properties of Calcium silicate hydrate (C-S-H)
Construction and Building Materials, 2020Co-Authors: Yohannes Lim Yaphary, Florence Sanchez, Chi Sun PoonAbstract:Abstract Calcium silicate hydrate layer (C-S-Hlayer) is considered to be the fundamental building block of hydrated cement. The effect of sodium ions on the atomic scale mechanical properties of C-S-Hlayer remains, however, unclear. Yet, this information is critical for understanding and predicting the macroscopic performance of concrete structures during their service life. Herein, the intrinsic mechanical properties of C-S-Hlayer with sodium-exchange ions replacing some Calcium Cations were studied by molecular dynamics simulations. The interatomic interactions provided insights into the role of Na+ within the atomistic scale of C-S-Hlayer. It was found that Na+ did not significantly alter the mechanical properties (i.e., strength and stiffness) of C-S-Hlayer. The larger Cationic attraction on the interlayer water molecules seen in the presence of Na+ occurred due to the exchange of two Na+ for one Calcium Cation and resulted in a volume expansion of C-S-Hlayer while a stiffening of its interlayer.
Yohannes Lim Yaphary - One of the best experts on this subject based on the ideXlab platform.
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effects of sodium Calcium Cation exchange on the mechanical properties of Calcium silicate hydrate c s h
Construction and Building Materials, 2020Co-Authors: Yohannes Lim Yaphary, Florence Sanchez, Chi Sun PoonAbstract:Abstract Calcium silicate hydrate layer (C-S-Hlayer) is considered to be the fundamental building block of hydrated cement. The effect of sodium ions on the atomic scale mechanical properties of C-S-Hlayer remains, however, unclear. Yet, this information is critical for understanding and predicting the macroscopic performance of concrete structures during their service life. Herein, the intrinsic mechanical properties of C-S-Hlayer with sodium-exchange ions replacing some Calcium Cations were studied by molecular dynamics simulations. The interatomic interactions provided insights into the role of Na+ within the atomistic scale of C-S-Hlayer. It was found that Na+ did not significantly alter the mechanical properties (i.e., strength and stiffness) of C-S-Hlayer. The larger Cationic attraction on the interlayer water molecules seen in the presence of Na+ occurred due to the exchange of two Na+ for one Calcium Cation and resulted in a volume expansion of C-S-Hlayer while a stiffening of its interlayer.
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Effects of sodium/Calcium Cation exchange on the mechanical properties of Calcium silicate hydrate (C-S-H)
Construction and Building Materials, 2020Co-Authors: Yohannes Lim Yaphary, Florence Sanchez, Chi Sun PoonAbstract:Abstract Calcium silicate hydrate layer (C-S-Hlayer) is considered to be the fundamental building block of hydrated cement. The effect of sodium ions on the atomic scale mechanical properties of C-S-Hlayer remains, however, unclear. Yet, this information is critical for understanding and predicting the macroscopic performance of concrete structures during their service life. Herein, the intrinsic mechanical properties of C-S-Hlayer with sodium-exchange ions replacing some Calcium Cations were studied by molecular dynamics simulations. The interatomic interactions provided insights into the role of Na+ within the atomistic scale of C-S-Hlayer. It was found that Na+ did not significantly alter the mechanical properties (i.e., strength and stiffness) of C-S-Hlayer. The larger Cationic attraction on the interlayer water molecules seen in the presence of Na+ occurred due to the exchange of two Na+ for one Calcium Cation and resulted in a volume expansion of C-S-Hlayer while a stiffening of its interlayer.
M. E. Meyerhoff - One of the best experts on this subject based on the ideXlab platform.
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Photonic crystal microcavity source based ion sensor
IEEE Sensors 2005., 2005Co-Authors: Swapnajit Chakravarty, J. Topolancik, P. K. Bhattacharya, Subhananda Chakrabarti, Y. Kang, M. E. MeyerhoffAbstract:An optical ion sensor based on the shifts of resonance of a photonic crystal microcavity coated with an ion sensing polymer is demonstrated. A 20nm shift is observed for perchlorate ion and a 5nm shift is observed for Calcium Cation
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Ion detection with photonic crystal microcavities
Optics Letters, 2005Co-Authors: Swapnajit Chakravarty, J. Topolancik, P. K. Bhattacharya, Subhananda Chakrabarti, Y. Kang, M. E. MeyerhoffAbstract:We have experimentally demonstrated a Cation and anion sensor by using short linear photonic crystal microcavities with an embedded quantum dot active region. The photonic crystal microcavity covered with an ion-selective polymer forms a submicrometer optical detection system sensitive to small changes of perchlorate anion (ClO4?) and Calcium Cation (Ca2+) concentrations.
Florence Sanchez - One of the best experts on this subject based on the ideXlab platform.
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effects of sodium Calcium Cation exchange on the mechanical properties of Calcium silicate hydrate c s h
Construction and Building Materials, 2020Co-Authors: Yohannes Lim Yaphary, Florence Sanchez, Chi Sun PoonAbstract:Abstract Calcium silicate hydrate layer (C-S-Hlayer) is considered to be the fundamental building block of hydrated cement. The effect of sodium ions on the atomic scale mechanical properties of C-S-Hlayer remains, however, unclear. Yet, this information is critical for understanding and predicting the macroscopic performance of concrete structures during their service life. Herein, the intrinsic mechanical properties of C-S-Hlayer with sodium-exchange ions replacing some Calcium Cations were studied by molecular dynamics simulations. The interatomic interactions provided insights into the role of Na+ within the atomistic scale of C-S-Hlayer. It was found that Na+ did not significantly alter the mechanical properties (i.e., strength and stiffness) of C-S-Hlayer. The larger Cationic attraction on the interlayer water molecules seen in the presence of Na+ occurred due to the exchange of two Na+ for one Calcium Cation and resulted in a volume expansion of C-S-Hlayer while a stiffening of its interlayer.
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Effects of sodium/Calcium Cation exchange on the mechanical properties of Calcium silicate hydrate (C-S-H)
Construction and Building Materials, 2020Co-Authors: Yohannes Lim Yaphary, Florence Sanchez, Chi Sun PoonAbstract:Abstract Calcium silicate hydrate layer (C-S-Hlayer) is considered to be the fundamental building block of hydrated cement. The effect of sodium ions on the atomic scale mechanical properties of C-S-Hlayer remains, however, unclear. Yet, this information is critical for understanding and predicting the macroscopic performance of concrete structures during their service life. Herein, the intrinsic mechanical properties of C-S-Hlayer with sodium-exchange ions replacing some Calcium Cations were studied by molecular dynamics simulations. The interatomic interactions provided insights into the role of Na+ within the atomistic scale of C-S-Hlayer. It was found that Na+ did not significantly alter the mechanical properties (i.e., strength and stiffness) of C-S-Hlayer. The larger Cationic attraction on the interlayer water molecules seen in the presence of Na+ occurred due to the exchange of two Na+ for one Calcium Cation and resulted in a volume expansion of C-S-Hlayer while a stiffening of its interlayer.
Lukasz Cwiklik - One of the best experts on this subject based on the ideXlab platform.
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the complex nature of Calcium Cation interactions with phospholipid bilayers
Scientific Reports, 2016Co-Authors: Adela Melcrova, Sarka Pokorna, Saranya Pullanchery, Miriam Kohagen, Piotr Jurkiewicz, Pavel Jungwirth, Paul S Cremer, Lukasz CwiklikAbstract:Understanding interactions of Calcium with lipid membranes at the molecular level is of great importance in light of their involvement in Calcium signaling, association of proteins with cellular membranes, and membrane fusion. We quantify these interactions in detail by employing a combination of spectroscopic methods with atomistic molecular dynamics simulations. Namely, time-resolved fluorescent spectroscopy of lipid vesicles and vibrational sum frequency spectroscopy of lipid monolayers are used to characterize local binding sites of Calcium in zwitterionic and anionic model lipid assemblies, while dynamic light scattering and zeta potential measurements are employed for macroscopic characterization of lipid vesicles in Calcium-containing environments. To gain additional atomic-level information, the experiments are complemented by molecular simulations that utilize an accurate force field for Calcium ions with scaled charges effectively accounting for electronic polarization effects. We demonstrate that lipid membranes have substantial Calcium-binding capacity, with several types of binding sites present. Significantly, the binding mode depends on Calcium concentration with important impliCations for Calcium buffering, synaptic plasticity, and protein-membrane association.
