A5090565921- Advanced X-ray Imaging Techniques
- Advanced Electron Microscopy Techniques and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced SAR Imaging Techniques
- ZnO doping and properties
- Autism Spectrum Disorder Research
- Synthetic Aperture Radar (SAR) Applications and Techniques
- Thin-Film Transistor Technologies
- Infrared Target Detection Methodologies
- Genetics and Neurodevelopmental Disorders
- Ion-surface interactions and analysis
- Radar Systems and Signal Processing
- Electronic and Structural Properties of Oxides
- Organic Light-Emitting Diodes Research
- Semiconductor materials and devices
- Cardiac Valve Diseases and Treatments
- Optical Systems and Laser Technology
- Tea Polyphenols and Effects
- Attention Deficit Hyperactivity Disorder
- Quantum Dots Synthesis And Properties
- Transition Metal Oxide Nanomaterials
- Congenital heart defects research
- Crystallography and Radiation Phenomena
- Alzheimer's disease research and treatments
- Mobile Agent-Based Network Management
Pohang University of Science and Technology
2018-2023
Korea Foundation for Max Planck POSTECH
2023
Gwangju Institute of Science and Technology
2021
LG Chem (South Korea)
2018
Korea Post
2018
LG (India)
2018
Heinrich Heine University Düsseldorf
2017
Keimyung University
1994-2016
Keimyung University Dongsan Medical Center
2016
Mokwon University
2015
Abstract The emergence of high repetition-rate X-ray free-electron lasers (XFELs) powered by superconducting accelerator technology enables the measurement significantly more experimental data per day than was previously possible. European XFEL is expected to provide 27,000 pulses second, over two orders magnitude any other XFEL. increased pulse rate a key enabling factor for single-particle diffractive imaging, which relies on averaging weak diffraction signal from single biological...
Abstract Despite more than a century of study, the fundamental mechanisms behind solid melting remain elusive at nanoscale. Ultrafast phenomena in materials irradiated by intense femtosecond laser pulses have revived interest unveiling puzzling processes transitions. However, direct experimental validation various microscopic models is limited due to difficulty imaging internal structures undergoing ultrafast and irreversible Here we overcome this challenge through time-resolved single-shot...
The age-specific prevalence of dementia, its sex difference, and the relative important types dementia were studied in elderly people a Korean rural community. A two-stage approach was employed, involving screening clinical assessment. among individuals aged 65 over found to be 10.8%, with rates 7.2% men 14.5% women. Alzheimer type 60.0% cases, multi-infarct 12.0%, mixed 10.7%, alcoholic 8.0%, others unclassifiable 9.3%. significantly higher women rapidly increased age both sexes. not...
The structures as building blocks for designing functional nanomaterials have fueled the development of versatile nanoprobes to understand local noncrystalline specimens. Progress in analyzing individual specimens with atomic scale accuracy has been notable recently. In most cases, however, only a limited number are inspected lacking statistics represent systems structural inhomogeneity. Here, by employing single-particle imaging X-ray free electron lasers and algorithms multiple-model 3D...
Femtosecond laser pulses drive nonequilibrium phase transitions via reaction paths hidden in thermal equilibrium. This stimulates interest to understand photoinduced ultrafast melting processes, which remains incomplete due challenges resolving accompanied kinetics at the relevant space-time resolution. Here, by newly establishing a multiplexing femtosecond X-ray probe, we have successfully revealed energy transfer processes confined Au nanospheres. Real-time images of electron density...
1. The effects of (–)-epigallocatechin gallate (EGCG), a green tea polyphenol, on glutamate-induced increases in intracellular Ca2+ concentrations ([Ca2+]i) and cytotoxicity PC12 cells were investigated. 2. Changes [Ca2+]i measured using Fura-2/AM calcium indicator dye cellular viabilities determined by viable cell count 3-(4,4-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assay. 3. Glutamate increased dose-dependent manner. (–)-Epigallocatechin attenuated this glutamate...
Ultrafast laser–excited nanoparticle images reveal nonequilibrium kinetics–driven unusual surface ordering at high temperature.
We developed a single-shot coherent X-ray imaging instrument at the hard beamline of Pohang Accelerator Laboratory Free Electron Laser (PAL-XFEL). This experimental platform was established to conduct variety XFEL experiments, including diffraction (CDI), photon correlation spectroscopy (XPCS), and scattering (CXS). Based on forward-scattering geometry, this utilizes fixed-target method for sample delivery. It is well optimized single-shot-based experiments in which one expects observe...
With each single X-ray pulse having its own characteristics, understanding the individual property of free-electron laser (XFEL) is essential for applications in probing and manipulating specimens as well diagnosing lasing performance. Intensive research using XFEL radiation over last several years has introduced techniques to characterize femtosecond pulses, but a simple characterization scheme, while not requiring ad hoc assumptions, address multiple aspects via data collection process...
White light-emitting diodes (LEDs) are used as a light source in many liquid-crystal displays (LCDs), with blue generated spectral distribution characteristic of white LEDs being potentially harmful to the human retina.We propose method for reducing only by calibration and profiling without adjusting.Specifically, this paper attempted verify efficacy colourimetric characterisation or controlling light.Based on test results LCD monitors that use variety LED sources, exhibited maximal emission...
Phase recovery is a well-known inverse problem prevalent across science disciplines and attracts active research interests to develop number of theoretical experimental methods. Recent developments in artificial intelligence have further prompted activities processing the experimentally collected imperfect data, but applications been limited slow-varying data such as real images. Experimental noise present largely fluctuating diffraction particular, adds practical challenges hamper...
The effect of the tin (Sn) concentration in zinc oxide (ZTO) films fabricated using a spin-coating process and its on ZTO channel thin film transistors (TFTs) with various Sn concentrations were examined. Spin-coated nanocrystalline had high transmittance (>85%) visible region. As increased, carrier resistivity (nc-ZTO) ranged from 9.6 × 1014 cm−3 to 2.2 1016 1.5 103 Ω-cm 1.6 102 Ω-cm, respectively. nc-ZTO TFTs that deposited as function Zn exhibited subthreshold gate voltage swing (S)...
Abstract IGZO nanoparticles were synthesized using a pulp processor at different temperatures and solution concentrations for the printing processes. The characterized by field emission scanning electron microscopy (FESEM), powder X‐ray diffraction (XRD) high resolution transmission (HRTEM). in 10% of 10–20 nm diameter. On other hand, 1 0.1% ∼10 diameter, as revealed HRTEM. From XRD HRTEM results, crystallinity decreased with decreasing concentration. In particular, was affected significantly indium
Photoinduced nonequilibrium phase transitions have stimulated interest in the dynamic interactions between electrons and crystalline ions, which long been overlooked within Born–Oppenheimer approximation. Ultrafast melting before lattice thermalization prompted researchers to revisit this issue understand ultrafast photoinduced weakening of crystal bonding. However, absence direct evidence demonstrating role orbital dynamics disorder leaves it elusive. By performing time-resolved resonant...
Unraveling nanoscale spin structures has long been an important activity addressing various scientific interests, that are also readily adaptable to technological applications.