A5103223360- melanin and skin pigmentation
- Biochemical Analysis and Sensing Techniques
- Analytical Chemistry and Chromatography
- Analytical chemistry methods development
- Advanced Chemical Sensor Technologies
- Phytochemicals and Antioxidant Activities
- Heavy metals in environment
- Effects and risks of endocrine disrupting chemicals
- Piperaceae Chemical and Biological Studies
- High Entropy Alloys Studies
- Nicotinic Acetylcholine Receptors Study
- Neuroendocrine regulation and behavior
- High-Temperature Coating Behaviors
- Additive Manufacturing Materials and Processes
- Advanced NMR Techniques and Applications
- Mercury impact and mitigation studies
- Chemistry and Chemical Engineering
- Nutrition, Health and Food Behavior
- Atomic and Subatomic Physics Research
- Cultural Heritage Materials Analysis
- Microfluidic and Capillary Electrophoresis Applications
- Mass Spectrometry Techniques and Applications
- Technology and Data Analysis
- Heavy Metal Exposure and Toxicity
- Solid-state spectroscopy and crystallography
Sungkyunkwan University
2010-2022
Korea Military Academy
2020
Amorepacific (South Korea)
2009-2012
Kumoh National Institute of Technology
2009
Dislocations in single-phase concentrated random alloys, including high-entropy alloys (HEAs), repeatedly encounter pinning during glide, resulting jerky dislocation motion. While solute-dislocation interaction is well understood conventional the origin of individual points a matter debate. In this work, we investigate CoCrFeMnNi HEA. In-situ transmission electron microscopy studies reveal wavy lines and jagged glide motion under external loading, even though no segregation or clustering...
Metals are commonly used in cosmetic products for blocking ultraviolet light or coloring pigments; however, some metals exceed specific concentrations and can cause serious safety issues such as skin troubles allergies. It is, therefore, important to measure the exact amount of metal products. However, cosmetics that contain many organic inorganic materials like oils, polymers, waxes, polyols, surfactants, metallic powders difficult analyze due matrix effect. In this study, we developed...
A simple and sensitive high-performance liquid chromatography (HPLC) method was developed for the determination of 19 preservatives in cosmetic matrices. The composition mobile phase optimized as a gradient to achieve lower detection limit when compared previously validated methods, sample preparation conditions were investigated optimize separation preservatives. C18 column used with methanol, 0.05 mol/L ammonium acetate buffer, water under elution conditions. Preservatives cosmetics...
The structures of a [Ni II , Cu —oxytocin] complex were investigated by electrospray ionization-mass spectrometry in positive mode. fragmentation patterns the + OT] 2+ analyzed tandem mass and multiple gas-phase. Conformations metal ion binding to oxytocin (OT) have been studied explain biological activity difference physiological solution. [Cu complexes observed as main ions MS spectra. Cys1–Tyr2–Ile3–Gln4 sequence is suggested be site for gas-phase Ile3–Gln4–Asn5–Cys6 complex. specific...
네일락카와 헤어스프레이 같은 화장품에 존재하는 미량의 프탈레이트를 정량분석하기 위하여, 가스크로마토그래피와 질량분석기를 사용한 효과적이면서 환경친화적인 분석방법을 개발하였다. 이들 화장품들은 다량의 유기용매를 함유되어 분석하기 위하여 널리 사용되는 시료의 클린업 방법이 적합하지 않았다. 더군다나 프탈레이트 분석시에는 실험과정 중에서의 오염으로 인해 실제보다 높은 분석값을 산출하게 되는 경우가 매우 많다. 이에 정확한 함량분석 및 이차오염을 방지하기 위해 사용하여 시료를 직접 희석하는 시료 전처리를 적용하였다. 이 분석방법은 정확성, 분석감도, 그리고 시료전처리를 간략히 할 수 있는 이점을 가진다. 화장품에서의 검출되는 빈도가 높고, 사람과 동물에 영향을 미치는 환경호르몬으로 보고되는 dibutyl phthalate (DBP)와 di (2-ethylhexyl) (DEHP) 두 종의 분석대상으로 선정하였다. 정량시 그 정확도 향상을 위해서 내부표준물질로 물질의 중수소치환체인...
To overcome the recent coronavirus pneumonia (COVID-19), several drug candidates are suggested and tested for latest clinical treatment. Chloroquine lopinavir showing definite effects after understand more about those roles in molecular level future application on NMR/MRI, hyperpolarization technique can open new opportunities diagnosis biomedical researches to cope with COVID-19. SABRE-based studies two carried out we observed hyperpolarized proton signals from whole structures, which be...
Abstract Flavokawains B and C (Ia,b) are isolated from the ethanolic extract of root Piper methysticum, which is found to inhibit melanogenesis in MSH‐activated B16 melanoma cells.
In this study, compared the critical control point (CCP) and limit (CL) of all confectionery companies certified with HACCP to improve management. The CCP CL insufficient management cases were analyzed from 2019 2021. As a result set lower than companies. So it is judged that should be reconfirmed for each food items. addition, related pre-requisite showed foreign materials such as hair vinyl. particular, vinyl which account high proportion cannot detected by an X-ray machine. Therefore,...
Synopsis An extremely small amount of several heavy metals have been detected in cosmetic products as impurities, which can cause skin allergies through percutaneous adsorption on the skin. We present here a fast, accurate, and highly sensitive method for simultaneous determination Pb 2+ , Fe Cu Ni Zn Co Cd Mn coloring agents products, to be evaluated by ion chromatography. All these are well separated bifunctional ion‐exchange column (IonPac CS5A) post‐column reaction spectrophotometric...