A5021066377- Analytical chemistry methods development
- Isotope Analysis in Ecology
- Nuclear Physics and Applications
- Mass Spectrometry Techniques and Applications
- Scientific Measurement and Uncertainty Evaluation
- Advanced Chemical Physics Studies
- Chemical Thermodynamics and Molecular Structure
- Radioactive contamination and transfer
- Radioactive Decay and Measurement Techniques
- Heavy Metals in Plants
- Spectroscopy and Laser Applications
- Heavy metals in environment
- Groundwater and Isotope Geochemistry
- Heavy Metal Exposure and Toxicity
- Atmospheric Ozone and Climate
- Water Quality Monitoring and Analysis
- Arsenic contamination and mitigation
- Ion-surface interactions and analysis
- Spectroscopy and Quantum Chemical Studies
- Laser-Matter Interactions and Applications
- Pesticide Residue Analysis and Safety
- Atmospheric chemistry and aerosols
- Extraction and Separation Processes
- Mercury impact and mitigation studies
- Zeolite Catalysis and Synthesis
Korea Research Institute of Standards and Science
2012-2023
Gwangju Health University
2010-2016
Daewoo Shipbuilding and Marine Engineering (South Korea)
2015
Institute of Public Health
2010
Environmental Research Institute
2010
Korea Advanced Institute of Science and Technology
2002-2008
Chemically modified graphene (CMG) nanoplatelets have shown great promise in various applications due to their electrical properties and high surface area. Chemical doping is one of the most effective methods tune electronic materials. In this work, novel B-doped (borane-reduced oxide, B-rG-O) were produced on a large scale via reduction oxide by borane-tetrahydrofuran adduct under reflux, use for supercapacitor electrodes was studied. This first report production from solution process...
Main text KRISS and NMIJ jointly coordinated the CCQM-K158 comparison on elements inorganic As in polished rice flour. The study comprised two parts, Part A B. Successful participation formal international comparisons is essential for documenting calibration measurement capability claims (CMCs) by national metrology institutes (NMIs) designated (DIs). specifically supports CMCs within food category, corresponding to sample matrix labeled "High organic content" new CC table broad claims....
Main text Twenty National Metrology Institutes and Designated registered in the CCQM Key Comparison of CCQM-K155 "Elements Tributyltin Seawater" nineteen institutes submitted their results. Participants were requested to evaluate mass fractions, expressed ng/g, arsenic, cadmium, copper, lead, nickel, zinc ng/kg level tributyltin seawater. Reference Values (KCRVs) are assigned various measurands by NIST decision tree approach (NDT). used analytical methods choice. Most participants employed...
Main text Aluminum oxide (Al 2 O 3 ), commonly referred to as alumina, is extensively used in a variety of applications fundamental material for ceramics, catalyst substrates, ingredients cosmetics, or media chromatography. High purity particular, plays crucial role the display and semiconductor industries. Trace elements such iron (Fe), magnesium (Mg) silicon (Si) high-purity alumina can significantly affect material's properties optical transparency mechanical strength, potentially...
In-plane or out-of-plane: Two low-energy states of the phenylthiyl radical were observed in photodissociation [D1]thiophenol. The relative orientation singly occupied molecular orbital (SOMO) distinguishes two species, namely X̃(B1) and Ã(B2). This is largely localized on sulfur atom exhibits atomic-orbital-like alignment with respect to plane (see picture).
The photodissociation dynamics of methylamines (CH3NH2 and CD3ND2) on the first electronically excited state has been investigated using velocity map ion imaging technique probing H or D fragment. Two distinct components are found in H(D) translational energy distribution, implying existence two different reaction pathways for bond dissociation. high component with small internal radical fragment is ascribed to N–H(D) fragmentation via coupling S1 upper-lying S2 repulsive potential surface...
Improved measurements on silicon crystal samples highly enriched in the 28Si isotope (known as 'Si28' or AVO28 material) have been carried out at PTB to investigate local isotopic variations original crystal. This material was used for determination of Avogadro constant NA and therefore plays an important role upcoming redefinition SI units kilogram mole, using fundamental constants. Subsamples extensively studied over past few years National Research Council (NRC, Canada), Metrology...
Photodissociation dynamics of 1,2-dibromopropane has been investigated at 234 and 265 nm by using the velocity map ion imaging method. At both pump energies, a single Gaussian-shaped speed distribution is observed for Br*((2)P(1/2)) fragment, whereas least three components are found to be existent Br((2)P(3/2)) product. The secondary C-Br bond cleavage bromopropyl radical which energized from ultrafast primary rupture should responsible multicomponent translational energy low kinetic region...
Objectives: The objective of this study was to evaluate the generating characteristics VOCs and exposure effect chemicals among laundry workers identify current status occupational safety health through check-ups. Methods: During six-month period from April September 2015, quantitatively measured seven in ten laundries carried out examinations on 35 workers. Results: Comparing monitoring results for laundries, they were classified into three groups by ventilation system, dry-cleaning size...
The 212.8-nm photodissociation dynamics of formic acid was investigated utilizing degenerate four-wave mixing spectroscopy. background-free rotational spectrum the nascent OH radicals obtained, and a cold energy distribution peaking at N″=3 extracted from DFWM spectrum. well approximated by Boltzmann with temperature Trot∼716 K, which corresponds to an average ∼498 cm−1. observation nonstatistical spin–orbit state distribution, preference for low-energy F1 manifold, implies absence any...
Photodissociation dynamics of iodoacetonitrile (ICH2CN) have been investigated at pump wavelengths 266 and 304 nm using a photofragment ion image velocity mapping technique. At both wavelengths, the prompt C-I bond rupture takes place on repulsive excited states to give I(2P3/2) I*(2P1/2), their speed spatial distributions are simultaneously measured. The recoil anisotropy parameter (beta) is determined be 1.10 1.60 for I I*, respectively, while it found much higher beta=1.70 1.90...
A paste‐type certified reference material ( CRM ) of tomato was developed for accurate elemental analysis canned foods. Accurate mass fractions cadmium (Cd), lead (Pb), and tin (Sn) in the paste were determined by isotope dilution inductively coupled plasma spectrometry. The values their expanded uncertainties k =2 at approximately 95% level confidence) Cd, Pb, Sn (0.297 ± 0.015) mg/kg, (0.213 0.010) (221.2 9.5) respectively. Homogeneity 0.3%, 1.8%, 0.2% Sn, respectively, which estimated...
An international comparison study on the accurate determination of molar mass M(Si) silicon artificially enriched in 28Si (x(28Si) > 0.9999 mol mol−1) has been completed. The measurements were part high level CCQM-P160 pilot assessing ability National Metrology Institutes (NMIs) and Designated (DIs) to make such at lowest possible levels measurement uncertainty identify difficulties when measuring this kind sample.
Isotope amount ratios are proving useful in an ever increasing array of applications that range from studies unravelling transport processes, to pinpointing the provenance specific samples as well trace element quantification by using isotope dilution mass spectrometry (IDMS). These expanding encompass fields diverse archaeology, food chemistry, forensic science, geochemistry, medicine and metrology. However, be effective tools, ratio data must reliable traceable enable comparability...
Main text Accurate and precise isotope ratio measurements of heavy elements are playing an increasingly important role in modern analytical sciences have numerous applications. Today, typically performed with two principal techniques: thermal ionization mass spectrometry (TIMS) multiple collector-inductively coupled plasma (MC-ICP-MS). To obtain accurate results by spectrometry, isotopic certified reference materials (iCRMs) needed for bias correction the validation method used analysis....
A certified reference material (CRM), NMIJ CRM 7203-a, was developed for the elemental analysis of tap water. At least two independent analytical methods were applied to characterize value each element. The elements in present as follows: Al, As, B, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, Rb, Sb, Se, Sr, and Zn. element given (property ± expanded uncertainty), with a coverage factor 2 uncertainty. uncertainties estimated while considering contribution methods, method-to-method...
Lead isotope amount ratios are commonly used in diverse fields such as archaeometry, geochemistry and forensic science. Currently, five reference materials with certified lead available, namely NIST SRM 981, 982 983, GBW ‐04442 NMIJ 3681‐a. Only 981 3681‐a have approximately natural isotopic compositions, is predominantly for correcting mass discrimination/mass fractionation the applied spectrometric procedures. Consequently, there no other material available to be validation and/or quality...
Liver plays a major role in metabolism and acts as source of energy for the body by storing glycogen. With growing interest investigation biological effects recent years, it is important necessary to develop accurate comparable analytical methods elements bio-samples. It has, however, been 10 years since tissue sample (bovine liver) CCQM-K49 key comparison. The purpose CCQM-K145 ensure traceable measurement results essential toxic such P, S, Zn, Mn, Ni, Mo, Sr, Cr, Co, Pb, As Hg bovine liver...
In der Ebene oder senkrecht dazu: Zwei energiearme Zustände des Phenylthiylradikals wurden bei Photodissoziation von [D1]Benzolthiol beobachtet – X̃(B1) und Ã(B2). Sie unterscheiden sich in relativen Orientierung einfach besetzten Molekülorbitals. Dieses Orbital ist weitgehend am Schwefelatom lokalisiert weist eine atomorbitalähnliche Ausrichtung relativ zur Molekülebene auf (siehe Bild).
Abstract Exact-matching double isotope dilution inductively coupled plasma mass spectrometry (ID-ICP/MS) is widely used to characterize reference materials (RMs) in elemental analysis. In this technique, achieving exactly matching ratios for the sample and calibration blends regarded as an important prerequisite obtaining accurate measurement results. However, meeting condition requires multiple time-consuming iterative measurements. current study, alternative approach that can avoid lengthy...