• Analytical Science and Technology
• /
• v.21 no.5
• /
• pp.438-441
• /
• 2008

We have developed an alternative to the internal chemical reference based on a calibrated reference signal which is not a real NMR line but an electronically produced signal (HERETIC) and determined the phosphorus concentration using this method. The area ratio of HERETIC and sample peaks obtained from the standard samples was used to measure the concentrations of different samples directly. The analysis of phosphorus by this method showed the excellent linear regression coefficient ($R^2=0.9999$) for the concentration range from 20 ppm to 500 ppm with HERETIC peak as reference.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.23 no.6
• /
• pp.661-668
• /
• 2017

The purpose of this study is to analyze the chemical reaction pathway for explosion accident of mixed cargo. The analysis used a structural scenario using event-tree analysis. Structural scenarios were constructed by estimating various chemical reaction paths in the content of the mixed cargo accident recorded in the written verdict. The analytical method was applied to three kinds of analysis: chemical analysis based on chemical theory, quantitative analysis using chemical reaction formula, and probabilistic analysis through questionnaire. As a result of analysis, the main pathway of the accident occurred in three ways: the path of explosion due to the reaction of concentrated sulfuric acid with water, the path of explosion due to the reaction of metal and mixed acid, and the path of explosion by synthesizing with special substances. This result is similar to the path recorded in the validation, and it leads to thar the proposed path analysis method is valid. The proposed method is expected to be applicable to chemical reaction path estimation of various chemical accidents.

• Journal of the Korean Magnetic Resonance Society
• /
• v.18 no.1
• /
• pp.36-40
• /
• 2014

Predicting secondary structure of protein through assigned backbone chemical shifts has been used widely because of its convenience and flexibility. In spite of its usefulness, chemical shift based analysis has some defects including isotopic shifts and solvent interaction. Here, it is shown that corrected chemical shift analysis for secondary structure of protein. It is included chemical shift correction through consideration of deuterium isotopic effect and calculate chemical shift index using probability-based methods. Enhanced method was applied successfully to one of the proteins from Mycobacterium tuberculosis. It is suggested that correction of chemical shift analysis could increase accuracy of secondary structure prediction of protein and small molecule in solution.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2001.11a
• /
• pp.144-148
• /
• 2001

• The Journal of Korean Institute for Practical Engineering Education
• /
• v.4 no.2
• /
• pp.84-90
• /
• 2012

It is described that the total analysis of CD-R, a digital recording media, including the planning and performing chemical analysis of cross sectional structure of recording layer, dye composition and chemical structure as an example of design for chemical analysis. Since chemical analysis of unknown sample is often involved the complicated process requiring many experiences and knowledge, students feel difficulties in planning the procedure of chemical analysis and selecting analytical methods. Thus, an example of chemical analysis is provided here to help student understanding the hole procedure of CD-R analysis. In this study, SEM is used to determine the cross sectional structure of PC substrate and recoding layer of CD-R. The dyes in recording layer is dissolved with solvent and separated with using TLC, analyzed with using UV-Vis absorption spectrometer. Then, the chemical structure of each component is determined with using GC-MS, NMR and mass spectrometer.

• Analytical Science and Technology
• /
• v.18 no.6
• /
• pp.475-482
• /
• 2005

The expression of uncertainty applied to the chemical analysis is highly recommended with increasing demands upon the systematic quality assurance and control(QA/QC) with ISO 17025. For the quantification of quality source, 7 major common sources of uncertainty, normally contributing to the quality of the chemical analysis, were selected from QA/QC literatures of chemical analysis. They were classified into repeatability, drift, uncertainty in standards, linearity of calibration, homogeneity, stability of sample, and matrix effect. And, the quantification of the sources by means of measurement uncertainty was proposed as a prerequisite steps for QA/QC. Examples applied to the quantification procedures of modelling, combination and expression of standard uncertainty for the 7 major common sources were presented as a reference guide for QA/QC in chemical analysis.

• Analytical Science and Technology
• /
• v.18 no.2
• /
• pp.168-172
• /
• 2005

A comparison study of XRF and $^{31}P$-NMR method for the analysis of phosphorous in lubricating oil has been described. Pure oil and water were used for the observation of matrices effect variation by different analytical methods. Quantitative analysis was carried out by XRF and $^{31}P$-NMR using real samples. Significant difference is observed from the slopes on the calibration curves by the XRF due to the matrices (water: 124.0, oil: 276.6). While the result obtained from XRF showed a large matrix effect, the slopes obtained from $^{31}P$-NMR results of two different matrices, however, are in good agreement ranged of ${\pm}9%$ (water: 4.9, oil: 5.3).

• 제어로봇시스템학회:학술대회논문집
• /
• 1995.10a
• /
• pp.31-34
• /
• 1995

The automated chemical analysis shop floor are developed for the environmental pollution problems in our chemical analysis center. This shop floor have the several equipments include weight, pour, dry, heater, boiler, mixture, spectroscopy etc. And the material handling components are made up by the stored stack, conveyore, turntables, robot etc. Computer simulation has been an important tool for these complete design problem. We have designed the arangement of chemical equipments and material flow systems by using the simulator "AutoModII". "AutoMoII" is one of the advanced simulator, CAD-like drawing tools with a powerful, engineering oriented language to model control logic and material flow. The result is the modeling of the chemical analysis system in accurate, three dimensional detail. We could designed the set able layout and scheduling system by using the AutoMoII simulator. AutoMoII simulator.

• Journal of the Korean Society of Safety
• /
• v.32 no.3
• /
• pp.21-27
• /
• 2017

Even if several chemical accident prevention systems such as PSM(Process Safety Management), RMP(Risk Management Plan), etc. have been carried out, many chemical accidents have still occurred at industrial plants in Korea. We describe the status of chemical industry and the trend of occurrence of chemical accidents in Korea. And this paper analyzes the recent chemical accidents in eight ways. These ways include chemical accident forms, ignition sources, sources of chemical equipment, human vs equipment/material causes, worker's working situation, employee scale, hazardous substances, week & time, fatalities of manufacture & contractor's workers. Finally we proposes the four representative prevention measures brought to result of cause analysis by accident statistics.

• Korean Journal of Hazardous Materials
• /
• v.2 no.1
• /
• pp.6-11
• /
• 2014

There have been frequent chemical leaks over the past 10 years. Particularly, inorganic acids like sulfuric acid, nitric acid, and hydrogen chloride take up 37 % of the total chemical accidents which took place for the past 10 years. When an acid chemical leak happens, fume is generated, diffusing into the air, which might cause serious damage to health of local residents and the environment. However, most of the acid-based chemicals, detecting and analysis methods have not been settled considering the frequency of accidents. In this study, we investigated detection and analysis methods to quickly analyze accident sites and evaluate the impacts on environments. Reviewing local and international test analysis methods of acids suggested that nitric acid, sulfuric acid, hydrogen chloride and hydrogen fluoride can be analyzed with IC. It was also found that UV is better for the analysis of hydrogen fluoride and GC/MS for acrylic acid. The analytical methods suggested in the official test methods basically have limitations of consuming much time at stages of preparation and analysis. Considering prompt responses to chemical accidents, further studies should be done to compare the applicability of rapid monitoring methods such as FT-IR, IMR-MS and SIFT-MS.