• Analytical Science and Technology
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• v.21 no.5
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• pp.345-363
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• 2008

Process analytics has been already widely utilized in a large-scale continuous production line such as petroleum industries for several decades. Although the process analytics has a long history, a concept of "Process Analytical Technology (PAT)" has been rapidly adopted as a new paradigm for the process monitoring in the production process of various industries. In this review, current status and recent developments of PAT in various research bodies have been introduced, including the introduction of various types of analytical instruments, chemometrics tools, and perspectives and future applications of PAT as well as the fundamentals on PAT such as terminology and its historical background.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.55-60
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• 1996

원자력발전소 운전시 원자로냉각재는 부식 방지를 위해 적절한 화학물질을 함유하고 있어야한다. 이러한 원자로냉각재의 수질화학 조절은 유량조절 기능과 화학제주입 기능을 가진 화학 및 체적제어계통의 화학제주입탱크 및 체적제어탱크에 의하여 이루어진다. 본 연구에서는 영광5,6호기에서 화학제주입계통의 연결위치를 충전펌프 후단에서 전단으로 변경하고, 원자로보충수펌프에 의하여 화학제주입을 수행할 경우 요구되는 주입운전시간 특성에 대해 수치해석을 이용하여 분석하였다. 분석은 설계요건에서 요구되는 화학제주입탱크의 용량 및 주입유량을 고정하고 탱크의 구조적형상 변경, disk block 설치 및 주입속도를 변경(입구배관 크기 변경)하여 각각의 경우에 대하여 시간변화에 대한 탱크 내에서의 유속분포, 농도분포, 평균농도 등 을 구하였다. 분석결과 발전소의 빠른 화학제주입운전을 위해서는 탱크 내에 혼합효과를 중대 시킬 수 있는 disk block의 설치가 요구됨을 알 수 있었다.

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

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

• Defense and Technology
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• no.7 s.281
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• pp.50-59
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• 2002

이 글은 독성 화학물질 테러 발생시 보다 신속하고 정확한 분석을 통해 대응능력을 향상시키고 대비태세를 더욱더 확고히 하기 위해 현재 널리 사용중인 기체분리 질량분석기(GC-MS : Gas Chromato-graph-Mass Spectrometer)와 액체분리 질량분석기의 최적의 분석기법, 미지시료 분석절차를 연구하였다. 독성 화학물질 공격에 대한 미국의 방어 대비책은 1991년 걸프전시 이라크의 화학무기 사용을 저지시키는데 일익을 담당하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.282-282
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• 2015

전자분광 화학분석(Electron Spectroscopy for Chemical Analysis : ESCA)은 고체표면의 구성원소 및 원소간 화학 결합 상태를 분석할 수 있는 효율적인 방법이다. ESCA 분석은 재료의 극표면층 (약 $20{\sim}100{\AA}$)에 분포되어 있는 원소 및 화학상태를 정성 정량적으로 확인할 수 있다. 또한, $Ar^+$이온을 충돌시켜 재료 표면을 ㎚단위로 식각 할 수 있기 때문에 수직분포 분석(Depth profiling)이 가능하여 나노재료가 활용되는 촉매, 반도체소자 그리고 박막 재료 등의 분석에 유용하게 활용될 수 있다. 이와 같은 분석적 장점에도 불구하고, ESCA 분석은 표면특성 분석에 주로 활용되는 주사전자현미경 및 X-선 미소분석(EDS, WDS) 등에 비하여 폭 넓게 사용되고 있지 못하다.

• Analytical Science and Technology
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• v.21 no.5
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• pp.438-441
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• 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 Chemical Society
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• v.66 no.3
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• pp.243-250
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• 2022

The purpose of this study was to investigate the inscription of North Korean Higher-Level Middle School 1 chemistry textbooks in the era of North Korean leader Kim Jong-un to understand North Korean chemistry education. The types and functions of inscription for each unit of the North Korean Higher-Level Middle School 1 Chemistry textbook were analyzed and compared with the inscription of the 'Chemistry I' textbook in South Korea. Inscriptions were analyzed by constructing an analysis frame based on previous studies. The analysis results were as follows. First, as for the types of inscription used in North Korean textbooks, photographs and illustrations were used the most, and graphs were used the least. Second, the functions of inscription used in North Korean textbooks had many exploratory and exemplary functions, and decorative functions were used the least. Third, there was no significant difference in type and function of textbook inscriptions from North and South Korea. The results of this study may be helpful in understanding North Korean chemistry education.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.320-321
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• 2003

대기중에 존재하는 입자상물질은 광범위한 입경역에 걸쳐서 다종다양한 미량화학성분으로 구성되는 분산체이고, 그 성상은 공간적으로도 시간적으로도 크게 변동한다. 입자상 물질의 화학분석법은 발생원 동정을 위한 자료로 적합하며 일반적으로는 습식의 파괴적인 원소분석으로 하는 경우가 많다. 일반적으로 화학적 분석법은 개별입자의 정보가 무시되며 필터에 포집된 bulk 시료에 의한 분석이 진행되므로 장시간 포집에 의한 단시간의 시간변동과 개개의 입자가 가지는 정보가 무시되고 평균화 되어버린다. (중략)

• Analytical Science and Technology
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• v.19 no.6
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• pp.504-511
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• 2006

Polysilanes with organic substituents such as methyl and phenyl were synthesized by Wurtz dechlorination-condensation reactions using ultrasonic from organochlorosilanes. The yields were compared with the results of thermal dechlorination-condensation reactions. Properties such as thermogravimetric analysis and photoreactivity were investigated for the possibility of applications.