The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform

Myongsoo Lee - One of the best experts on this subject based on the ideXlab platform.

  • Substrate-Driven Transient Self-Assembly and Spontaneous Disassembly Directed by Chemical Reaction with Product Release
    2019
    Co-Authors: Huaxin Wang, Yanyan Wang, Bowen Shen, Xin Liu, Myongsoo Lee
    Abstract:

    The chemical reactivity of Molecules can be significantly enhanced when they are trapped in a confined space. Although such a confinement effect can be found in many self-assembled nanostructures, dissipation after completing the reaction to release the product remains elusive. Here we report substrate-directed transient self-assembly for accelerating a chemical reaction and spontaneous disassembly with releasing the products. The hydrophobic substrates mediate self-assembly of a dissolved pyridine-based amphiphile to provide a confined space to promote an aromatic nucleophilic substitution (SNAr) reaction in water. The chemical reaction triggers disassembly of the aggregates with simultaneous release of the product that can be spontaneously separated out of the solution by precipitation. Neutralization of the Amphiphilic Molecule leads to a new cycle of self-assembly entrapping substrates and disassembly with releasing the product

  • Molecular reorganization of paired assemblies of T-shaped rod-coil Amphiphilic Molecule at the air-water interface.
    Langmuir, 2008
    Co-Authors: Libin Liu, Kyung-soo Moon, Ray Gunawidjaja, Eunji Lee, Vladimir V. Tsukruk, Myongsoo Lee
    Abstract:

    A T-shaped aromatic Amphiphilic Molecule based on linear oligo(ethylene oxide) was synthesized. We suggest that its peculiar interfacial behavior at the air−water interface and the structure of the Langmuir−Blodgett monolayer are associated with its peculiar T-shape and competing steric and Amphiphilic interactions at different surface pressures. At low surface pressure, uniform and smooth monolayers were formed. Upon compression, the molecular reorganization from spherical to cylindrical transformation occurred, as caused by the submerging of the oligo(ethylene oxide) chains, providing for efficient π−π interactions of the central core. At the highest surface pressure, the monolayer collapses into bilayer domains, following a bicontinuous network formation which tends to transform into a perforated film. The unique shape of T-like rigid aromatic cores makes their structural reorganization very peculiar with paired, dimerlike molecular packing dominating in gas and solid states. This paired aggregation is...

Lihong Dong - One of the best experts on this subject based on the ideXlab platform.

  • Amphiphilic Molecule controlled synthesis of cuo nano micro superstructure film with hydrophilicity and superhydrophilicity surface
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2009
    Co-Authors: Jing Xiao, Ying Chu, Yujiang Zhuo, Lihong Dong
    Abstract:

    This paper described how we obtained cupric oxide (CuO) nano/micro superstructure film with hydrophilicity and superhydrophilicity surfaces by a controllable synthesis of Amphiphilic Molecule, cetyltrimethylammonium bromide (CTAB) and polyethylene glycol-6000(PEG), via a simple solution-immersion process on Cu foil at room-temperature. A series of control experiments indicated that the concentration of NaOH, the concentration and the species of the Amphiphilic Molecule had directly influenced the morphology and wettability of the products. Because of their novel structure and wettability, the CuO films could be a promising material for fabricating optical switches, solar cells and catalyst or could be used as a gas-sensing medium. And the wettability of the CuO films may be used in some areas.

  • Amphiphilic Molecule controlled synthesis of CuO nano/micro-superstructure film with hydrophilicity and superhydrophilicity surface
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2009
    Co-Authors: Jing Xiao, Ying Chu, Yujiang Zhuo, Lihong Dong
    Abstract:

    This paper described how we obtained cupric oxide (CuO) nano/micro superstructure film with hydrophilicity and superhydrophilicity surfaces by a controllable synthesis of Amphiphilic Molecule, cetyltrimethylammonium bromide (CTAB) and polyethylene glycol-6000(PEG), via a simple solution-immersion process on Cu foil at room-temperature. A series of control experiments indicated that the concentration of NaOH, the concentration and the species of the Amphiphilic Molecule had directly influenced the morphology and wettability of the products. Because of their novel structure and wettability, the CuO films could be a promising material for fabricating optical switches, solar cells and catalyst or could be used as a gas-sensing medium. And the wettability of the CuO films may be used in some areas.

Bowen Shen - One of the best experts on this subject based on the ideXlab platform.

  • substrate driven transient self assembly and spontaneous disassembly directed by chemical reaction with product release
    Journal of the American Chemical Society, 2019
    Co-Authors: Huaxin Wang, Yanyan Wang, Bowen Shen
    Abstract:

    The chemical reactivity of Molecules can be significantly enhanced when they are trapped in a confined space. Although such a confinement effect can be found in many self-assembled nanostructures, dissipation after completing the reaction to release the product remains elusive. Here we report substrate-directed transient self-assembly for accelerating a chemical reaction and spontaneous disassembly with releasing the products. The hydrophobic substrates mediate self-assembly of a dissolved pyridine-based amphiphile to provide a confined space to promote an aromatic nucleophilic substitution (SNAr) reaction in water. The chemical reaction triggers disassembly of the aggregates with simultaneous release of the product that can be spontaneously separated out of the solution by precipitation. Neutralization of the Amphiphilic Molecule leads to a new cycle of self-assembly entrapping substrates and disassembly with releasing the product.

  • Substrate-Driven Transient Self-Assembly and Spontaneous Disassembly Directed by Chemical Reaction with Product Release
    2019
    Co-Authors: Huaxin Wang, Yanyan Wang, Bowen Shen, Xin Liu, Myongsoo Lee
    Abstract:

    The chemical reactivity of Molecules can be significantly enhanced when they are trapped in a confined space. Although such a confinement effect can be found in many self-assembled nanostructures, dissipation after completing the reaction to release the product remains elusive. Here we report substrate-directed transient self-assembly for accelerating a chemical reaction and spontaneous disassembly with releasing the products. The hydrophobic substrates mediate self-assembly of a dissolved pyridine-based amphiphile to provide a confined space to promote an aromatic nucleophilic substitution (SNAr) reaction in water. The chemical reaction triggers disassembly of the aggregates with simultaneous release of the product that can be spontaneously separated out of the solution by precipitation. Neutralization of the Amphiphilic Molecule leads to a new cycle of self-assembly entrapping substrates and disassembly with releasing the product

Jing Xiao - One of the best experts on this subject based on the ideXlab platform.

  • Amphiphilic Molecule controlled synthesis of cuo nano micro superstructure film with hydrophilicity and superhydrophilicity surface
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2009
    Co-Authors: Jing Xiao, Ying Chu, Yujiang Zhuo, Lihong Dong
    Abstract:

    This paper described how we obtained cupric oxide (CuO) nano/micro superstructure film with hydrophilicity and superhydrophilicity surfaces by a controllable synthesis of Amphiphilic Molecule, cetyltrimethylammonium bromide (CTAB) and polyethylene glycol-6000(PEG), via a simple solution-immersion process on Cu foil at room-temperature. A series of control experiments indicated that the concentration of NaOH, the concentration and the species of the Amphiphilic Molecule had directly influenced the morphology and wettability of the products. Because of their novel structure and wettability, the CuO films could be a promising material for fabricating optical switches, solar cells and catalyst or could be used as a gas-sensing medium. And the wettability of the CuO films may be used in some areas.

  • Amphiphilic Molecule controlled synthesis of CuO nano/micro-superstructure film with hydrophilicity and superhydrophilicity surface
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2009
    Co-Authors: Jing Xiao, Ying Chu, Yujiang Zhuo, Lihong Dong
    Abstract:

    This paper described how we obtained cupric oxide (CuO) nano/micro superstructure film with hydrophilicity and superhydrophilicity surfaces by a controllable synthesis of Amphiphilic Molecule, cetyltrimethylammonium bromide (CTAB) and polyethylene glycol-6000(PEG), via a simple solution-immersion process on Cu foil at room-temperature. A series of control experiments indicated that the concentration of NaOH, the concentration and the species of the Amphiphilic Molecule had directly influenced the morphology and wettability of the products. Because of their novel structure and wettability, the CuO films could be a promising material for fabricating optical switches, solar cells and catalyst or could be used as a gas-sensing medium. And the wettability of the CuO films may be used in some areas.

Alfred Blume - One of the best experts on this subject based on the ideXlab platform.

  • A T-shaped Amphiphilic Molecule forms closed vesicles in water and bicelles in mixtures with a membrane lipid.
    The Journal of Physical Chemistry B, 2012
    Co-Authors: Peggy Scholtysek, Anja Achilles, Claudia-viktoria Hoffmann, Bob-dan Lechner, Annette Meister, Carsten Tschierske, Kay Saalwächter, Katarina Edwards, Alfred Blume
    Abstract:

    The T-shaped Amphiphilic Molecule A6/6 forms a columnar hexagonal liquid-crystalline phase between the crystalline and the isotropic liquid when studied in bulk (Chen et al., 2005). Because of the hydrophilic and flexible oligo(oxyethylene) side chain terminated by a 1-acylamino-1-deoxy-d-sorbitol moiety attached to a rigid terphenyl core with terminal hexyloxy alkyl chains, it was expected that also formation of lyotropic phases could be possible. We therefore studied the behavior of A6/6 in water and also in mixtures with bilayer-forming phospholipids, such as dipalmitoyl-phosphatidylcholine (DPPC), using differential scanning calorimetry (DSC), transmission electron microscopy (TEM), cryo-transmission electron microscopy (cryo-TEM), dynamic light scattering (DLS), and solid-state nuclear magnetic resonance (ssNMR). DSC showed for the pure A6/6 suspended in water a phase transition at ca. 23 °C. TEM and cryo-TEM showed vesicular as well as layered structures for pure A6/6 in water below and above this p...

  • A T-Shaped Amphiphilic Molecule Forms Closed Vesicles in Water and Bicelles in Mixtures with a Membrane Lipid B
    The Journal of Physical Chemistry, 2012
    Co-Authors: Peggy Scholtysek, Anja Achilles, Claudia-viktoria Hoffmann, Bob-dan Lechner, Annette Meister, Carsten Tschierske, Kay Saalwächter, Katarina Edwards, Alfred Blume
    Abstract:

    The T-shaped Amphiphilic Molecule A6/6 forms a columnar hexagonal liquid-crystalline phase between the crystalline and the isotropic liquid when studied in bulk (Chen et al., 2005). Because of the hydrophilic and flexible oligo(oxyethylene) side chain terminated by a 1-acylamino-1-deoxy-d-sorbitol moiety attached to a rigid terphenyl core with terminal hexyloxy alkyl chains, it was expected that also formation of lyotropic phases could be possible. We therefore studied the behavior of A6/6 in water and also in mixtures with bilayer-forming phospholipids, such as dipalmitoyl-phosphatidylcholine (DPPC), using differential scanning calorimetry (DSC), transmission electron microscopy (TEM), cryo-transmission electron microscopy (cryo-TEM), dynamic light scattering (DLS), and solid-state nuclear magnetic resonance (ssNMR). DSC showed for the pure A6/6 suspended in water a phase transition at ca. 23 °C. TEM and cryo-TEM showed vesicular as well as layered structures for pure A6/6 in water below and above this phase transition. By atomic force microscopy (AFM), the thickness of the layer was found to be 5–6 nm. This leads to a model for a bilayer formed by A6/6 with the laterally attached polar side chains shielding the hydrophobic layer built up by the terphenyl core with the terminal alkyl chains of the Molecules. For DPPC:A6/6 mixtures (10:1), the DSC curves indicated a stabilization of the lamellar gel phase of DPPC. Negative staining TEM and cryo-TEM images showed planar bilayers with hexagonal morphology and diameters between 50 and 200 nm. The hydrodynamic radius of these aggregates in water, investigated by dynamic light scattering (DLS) as a function of time and temperature, did not change indicating a very stable aggregate structure. The findings lead to the proposition of a new bicellar structure formed by A6/6 with DPPC. In this model, the bilayer edges are covered by the T-shaped Amphiphilic Molecules preventing very effectively the aggregation to larger structures.