A5101692947- Aluminum Alloy Microstructure Properties
- 2D Materials and Applications
- Aluminum Alloys Composites Properties
- Structural Behavior of Reinforced Concrete
- MXene and MAX Phase Materials
- Metallurgy and Material Forming
- Advanced Sensor and Energy Harvesting Materials
- Graphene research and applications
- Structural Analysis and Optimization
- Catalytic Processes in Materials Science
- Mechanical Behavior of Composites
- 3D Printing in Biomedical Research
- Structural Load-Bearing Analysis
- Optical Polarization and Ellipsometry
- Surface Modification and Superhydrophobicity
- Catalysis and Oxidation Reactions
- Seismic and Structural Analysis of Tall Buildings
- Solidification and crystal growth phenomena
- Seismic Performance and Analysis
- Protein Structure and Dynamics
- thermodynamics and calorimetric analyses
- Graphene and Nanomaterials Applications
- Advanced Battery Materials and Technologies
- Semiconductor materials and devices
- Innovative Microfluidic and Catalytic Techniques Innovation
Daejin University
2025
Korea Post
2024
Pohang University of Science and Technology
2024
United States Naval Research Laboratory
2015-2024
Korea Institute of Industrial Technology
2009-2023
Kyungsung University
2021-2023
Seoul National University of Science and Technology
2022-2023
Korea Electric Power Corporation (South Korea)
2022
Naval Research Laboratory Materials Science and Technology Division
2021
Hanyang University
2021
Abstract The high-volume synthesis of two-dimensional (2D) materials in the form platelets is desirable for various applications. While water considered an ideal dispersion medium, due to its abundance and low cost, hydrophobicity platelet surfaces has prohibited widespread use. Here we exfoliate 2D directly pure without using any chemicals or surfactants. In order disperse water, elevate temperature sonication bath, introduce energy via dissipation sonic waves. Storage stability greater...
We investigated the optical properties of ultrathin MoS2 films (number layers: N = 1, 2, 4, and 12) using Raman spectroscopy, photoluminescence (PL) spectroscopic ellipsometry. estimated layer thicknesses based on spectra. characterized microstructural a single-layer film atomic force microscopy. measured lowest-energy A B excitons PL spectroscopy. ellipsometric angles (Ψ Δ) thin ellipsometry, obtained dielectric functions as films' thickness changed from single to multi-layers. determined...
Chemical transformation of existing two-dimensional (2D) materials can be crucial in further expanding the 2D crystal palette required to realize various functional heterostructures. In this work, we demonstrate a 'on-stack' chemical conversion single-layer crystalline MoS2 into MoO3 with precise layer control that enables truly and MoO3/MoS2 To minimize perturbation morphology, nonthermal oxidation using O2 plasma was employed. The early stage reaction characterized by defect-induced Raman...
Monolayer MoS2 nanosheets are potentially useful in optoelectronics, photoelectronics, and nanoelectronics due to their flexibility, mechanical strength, direct band gap of 1.89 eV. Experimentalists have studied the synthesis using chemical vapor deposition (CVD) methods an effort fabricate wafer-scale nanofilms with a high uniformity continuity for practical electronic applications. In this work, we applied CVD method reaction MoO3 powder H2S gas grow high-quality polycrystalline monolayer...
Non-line-of-sight techniques are well suited for fabrication of thin and conformal solid-state electrolyte coatings, especially within three-dimensionally porous electrode architectures.
A newly designed single-chamber system is equipped with Ni/Cr alloy wires that work as the heating filaments in initiated chemical vapor deposition (iCVD) and also RF plasma generating electrode atomic layer (ALD) for facilitating manufacturing of organic/inorganic hybrid thin film encapsulation (TFE). The total processing time was noticeably reduced because temperature ALD could be decreased to iCVD by adopting enhanced (PE-ALD) instead conventional thermal ALD. previously reported using...
ABSTRACT Post‐maintenance crack size distribution is assumed to be the same as initial for conventional structural reliability analysis (SRA). This may true replacement; however, other maintenance methods, including blending and repair welding, will likely have significantly different distribution. Bayesian search theory was applied estimate distribution, which critical SRA of aircraft structures due its high uncertainty. The basic idea formulate a likelihood function that filters unlikely...
The absorption of drugs via oral route is a subject great interest in drug development process. current vitro method for measuring the kinetics relies on 2-D monolayer culture Caco-2 cells porous membrane, but physiologically unrealistic environment provided by this often results inaccurate kinetics. Here we report novel microfluidic system which better mimics physiological human small intestine. Three dimensional geometries villi intestine were reproduced hydrogel microfabrication...
A progressive failure model for laminated composite beams is formulated using a beam finite element with layer-wise constant shear (BLCS), which permits accurate computation of stresses on each layer. This the first study to incorporate stress-prediction accuracy prediction laminates under bending loads. In present formulation, based material degradation factors and existing criteria, linear elastic behavior assumed, damaged layer in an substituted by degraded homogeneous Maximum Stress...
The production of hole and Mo cluster by electron beam irradiation in molybdenum disulfide (MoS2), which consists S-Mo-S layers, is monitored over time using atomic resolution transmission microscopy. S vacancies are firstly formed due to knocking off atoms then line defects induced accumulation MoS2 sheet instead forming a hole. tend be merged at point subsequently the point. clustered discretely as nano along edge difference displacement threshold energy between under irradiation. After...
We describe an efficient chemical vapor deposition (CVD) method for synthesizing graphene with a single crystal orientation on the whole surface of copper (Cu) foil. specifically synthesized inner folded Cu foil, which small holes were made regulating permeation and adsorption gases used synthesis. compared results this method, we call "hole-pocket" previously developed methods involving traditional synthesis open foil "pita-pocket". From these comparisons, found recrystallized to depend...
The confined nanospace of organic nanotubes protects enzymes against thermal denaturation and preserves catalytic activity following prolonged elevated temperature exposure.
Abstract A series of TiO 2 ‐supported Pd catalysts with different amounts ionic liquid (IL) were synthesized for the selective hydrogenation acetylene to ethylene in excess ethylene. CO Fourier transform infrared spectroscopy (FTIR), high‐angle annular dark‐field‐scanning transmission electron microscopy (HAADF‐STEM), and X‐ray photoelectron (XPS) suggested that species via strong electrostatic adsorption (SEA) method exist predominantly as isolated atoms on independent presence IL. Using a...
The adhesion interactions of two-dimensional (2D) materials are importance in developing flexible electronic devices due to relatively large surface forces. Here, we investigated the properties large-area monolayer MoS2 grown on silicon oxide by using chemical vapor deposition. Fracture mechanics concepts double cantilever beam configuration were used characterize interaction between and oxide. While interface was fractured under displacement control, force-displacement response recorded....
Poly(dimethylsiloxane) has attracted much attention in soft lithography and also been preferred as a platform for photochemical reaction, thanks to its outstanding characteristics including ease of use, nontoxicity, high optical transmittance. However, the low stiffness PDMS, an obvious advantage lithography, is often treated obstacle conducting precise handling or maintaining structural integrity. For these reasons, Glass-PDMS-Glass structure emerged straightforward alternative....
Grid-pattern framing of tubular structures for tall buildings is becoming popular because its aesthetic appeal. The recently developed hexagrid pattern constitutes an innovative shape from both architectural and structural perspectives. This study investigated the characteristics buildings, focusing on size modules, proposed a sizing formula based stiffness-design criteria members in preliminary design stage. An analysis 60-story revealed findings that are worthy consideration
High pressure die casting is one of the precision methods. It highly productivity and suitable for manufacturing components with complex shapes accurate dimensions. Recently, there has been increasing demand efficient heat dissipation components, to control generated by devices, which directly affects efficiency life product. Die cast aluminum alloys high thermal conductivity are especially needed this application. In study, influence elements added alloy on its was evaluated. The results...