• Nuclear Engineering and Technology
• /
• v.48 no.2
• /
• pp.299-303
• /
• 2016

Prompt gamma activation analysis using a thermal neutron-guided beam at Japan Atomic Energy Agency JRR-3M was applied for the precise determination of Si in silicon nitride ceramic reference materials [Japan Ceramic Reference Material (JCRM) R 003]. In this study, the standard addition method coupled with internal standard was used for the nondestructive determination of Si in the sample. Cadmium was used as internal standard to obtain the linear calibration curves and to compensate for the neutron beam variability. The analytical result of determining Si in JCRM R 003 silicon nitride fine powder ceramic reference materials using prompt gamma activation analysis was in good agreement with that obtained by classical gravimetric analysis. The relative expanded measurement uncertainty (k = 2) associated with the determined value was 2.4%.

• Journal of Korean Society for Atmospheric Environment
• /
• v.21 no.4
• /
• pp.423-430
• /
• 2005

This study was investigated with sample digestion techniques and a reliability of the analytical results for a quantitative analysis of a standard reference material ('urban particulate matter', SRM 1648). The metallic elements were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) with closed vessel microwave acid digestion method and atomic absorption spectroscopy (AAS). Quality control of the overall analytical procedures for metallic element determinations of standard reference material were estimated by analysis of a SRM 1648. Three digestion solutions $(type\;1:\;HNO_3,\;type\;2:\;HNO_3\;and\;H2O_2(4'1)\;mixture,\;type\;3:5.55\%\; HNO_3\;and\;16.75\%\;HCI\;mixture)$ were applied to SRM 1648. As a result, three digestion solutions used in this study are completely unable to digest Cr of SRM 1648. Reliability of Cr and As showed some errors in the digestion with digestion solution type (3) due to the influence of chlorides. Type (3) digestion solutions are sufficient to fulfill the digestion of As as well as Se in SRM 1648. ICP-MS results showed the improvement in accurate and precise determination of some trace elements like Cd, V and Pb in SRM 1648. It is important to use the proper digestion solution for each element to qualify analytical precision.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.17 no.4
• /
• pp.159-169
• /
• 2013

The purpose of this study is to investigate the inelastic behavior of hollow reinforced concrete bridge column sections with reinforcement details for material quantity reduction and to provide the details and reference data. Among the numerous parameters, this study concentrates on the shape of the section, the reinforcement details, the diameter of the transverse reinforcement and loading types. Eighteen column section specimens were tested under quasi-static monotonic loading. In this study, the computer program RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology) was used. A modified lateral confining effect model was adopted for the hollow bridge column sections. This study documents the testing of hollow reinforced concrete bridge column sections with reinforcement details for material quantity reduction and presents conclusions based on the experimental and analytical findings.

• Journal of Ginseng Research
• /
• v.35 no.4
• /
• pp.487-496
• /
• 2011

Good manufacturing practice (GMP)-based quality control is an integral component of the common technical document, a formal documentation process for applying a marketing authorization holder to those countries where ginseng is classified as a medicine. In addition, authentication of the physico-chemical properties of ginsenoside reference materials, and qualitative and quantitative batch analytical data based on validated analytical procedures are prerequisites for certifying GMP. Therefore, the aim of this study was to propose an authentication process for isolated ginsenosides $Rb_1$ and $Rg_1$ as reference materials (RM) and for these compounds to be designated as RMs for ginseng preparations throughout the world. Ginsenoside $Rb_1$ and $Rg_1$ were isolated by Diaion HP-20 adsorption chromatography, silica gel flash chromatography, recrystallization, and preparative HPLC. HPLC fractions corresponding to those two ginsenosides were recrystallized in appropriate solvents for the analysis of physico-chemical properties. Documentation of the isolated ginsenosides was made according to the method proposed by Gaedcke and Steinhoff. The ginsenosides were subjected to analyses of their general characteristics, identification, purity, content quantitation, and mass balance tests. The isolated ginsenosides were proven to be a single compound when analyzed by three different HPLC systems. Also, the water content was found to be 0.940% for $Rb_1$ and 0.485% for $Rg_1$, meaning that the net mass balance for ginsenoside $Rb_1$ and $Rg_1$ were 99.060% and 99.515%, respectively. From these results, we could assess and propose a full spectrum of physicochemical properties for the ginsenosides $Rb_1$ and $Rg_1$ as standard reference materials for GMP-based quality control.

• Analytical Science and Technology
• /
• v.30 no.5
• /
• pp.240-251
• /
• 2017

1,1,1,2-Tetrafluoroethane (HFC-134a), which is used as refrigerant in air conditioners, has been recently regulated as a greenhouse gas and is recommended for reuse by refining. It is very important to quantitatively analyze trace impurities present in the refrigerant to evaluate the criteria for reuse. In this study, trace impurities including C, H, Cl, and F, which are difficult to quantify because there are no reference materials, were quantitatively analyzed by a gas chromatograph-atomic emission detector (GC/AED); for this analysis, this was preceded by a qualitative analysis with a GC-mass selective detector (GC/MSD). In addition, the AED response was investigated using a hydrocarbon mixed reference material, which was proportional to the number of atoms in the component. Fifteen refrigerant components were detected as trace impurities in HFC-134a by qualitative analysis of trace impurities including C, H, Cl, and F in the samples. Based on the results of the qualitative analysis, quantitative analysis of trace impurities using AED showed that the highest mole fractions were for the $CHClF_2$ component ($45438.38{\mu}mol/mol$) in one sample and for the $C_2H_2ClF_3$ component ($1311.47{\mu}mol/mol$) in another sample. From this study, it has been shown that it is possible for this analytical method to be applied to the qualitative and quantitative analysis of trace compounds in refrigerants, which are difficult to quantify because of the absence of reference materials.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.10
• /
• pp.3485-3488
• /
• 2012

• Analytical Science and Technology
• /
• v.15 no.4
• /
• pp.335-340
• /
• 2002

An analytical method has been developed to determine multi-elements in human hair samples by inductively coupled plasma mass spectrometry (ICP-MS). 0.05 g of hair sample was added to the Teflon digestion bomb together with 1.5 mL of nitric acid and an appropriate amount of In as an internal standard. The sample was then decomposed in the microwave digestion system. The hair certified reference material, GBW 09101, was analyzed for the validation of the analytical method. The determined values were in good agreement with the certified values within the uncertainty range.

• Analytical Science and Technology
• /
• v.14 no.2
• /
• pp.115-122
• /
• 2001

Butyltin compounds, including mono-(MBT), di-(DBT) and tributyltin(TBT) were analyzed in 44 human blood samples randomly collected from a hospital in "K" a city. Gas chromatograph equipped with flame photometric detector(FPD) was used to quantify the amounts of butylin compounds. Method detection limits(MDL) of this analytical method were 3.69ng Sn/g for MBT, 0.91ng Sn/g for DBT and 1.09ng Sn/g wet wt for TBT respectively. Standard reference material(SRM) containing of $1.3{\mu}g/g$ TBT as chloride was analyzed to check if this analytical results would be reliable. Recovery of about 90% was obtained through this analysis, indicating that the analytical method from butyltin compounds blood was reliable. The concentrations of butyltin compounds ranged MDL(<3.69) to 7.93ng Sn/g for MBT and 1.15 to 5.41ng Sn/g wet wt for DBT. Tributyltin was below detection limit in all samples. Detection limits of our results are lower than those reported by Kannan et al. who reported butyltin compounds in 33 human blood samples in the United States. Detection of MBT and DBT on blood sample implies that butyltin compounds could be absorbed through consumption of seafoods or exposure to food stuffs made of plastics and household items. Further study is needed to examine if butyltin compounds in blood can be reliably analyzed and used as intake index.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.11
• /
• pp.1541-1544
• /
• 2002

The concentration of B in steels is important due to its influence on mechanical properties of steel such as hardenability, hot workability, and creep resistance. An analytical method has been developed to determine B in steel samples by high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). National Institute of Standard and Technology Standard Reference Material (NIST SRM) 348a was analyzed to validate the analytical method. The steel sample was digested in a centrifuge bottle with addition of aqua regia and $^{10}B$ spike isotope. Sample pH was then adjusted to higher than 10 to precipitate most matrix elements such as Fe, Cr, and Ni. After centrifugation, the supernatant solution was passed through a cation exchange column to enhance the matrix separation efficiency. B recovery efficiency was about 37%, while matrix removal efficiency was higher than 99.9% for major matrix elements. The isotope dilution method was used for quantification and the determined B concentration was in good agreement with the certified value.

• Analytical Science and Technology
• /
• v.23 no.6
• /
• pp.615-618
• /
• 2010

An oxygen bomb combustion procedure were studied for determination of heavy metal in polymer materials such as polyvinyl chloride and polypropylene by ICP-AES. This method is proposed as a rapid and simple sample preparation for decomposition of polymer containing certified contents of the analytes by teflon coated oxygen bomb combustion using different absorbing solution. The recoveries of metal were found to be 30~102% from absorbed solution by ICP-AES method using polypropylene certified reference material(PP CRM-As, Ba, Cd, Hg, Pb, Zn). The recoveries of metal using PVC CRM(Cd, Hg, Pb) was found to be 45 ~101% with same procedures.