• 대한화학회지
• /
• 제37권6호
• /
• pp.590-598
• /
• 1993

미국의 환경청이 지정한 129종의 priority pollutants 중 16종의 유기살충제를 대상물질로 선정하여 수질시료 중의 극미량 분석방법을 연구하였다. 분석방법으로는 기체크로마토그래프-전자포획 및 기체크로마토그래프/질량분석기-SIM(selected ion moitoring)법을 검출방법으로 정하고, 시료용액의 추출 및 농축방법으로는 용매추출법(liquid-liquid extraction)과 고체상 추출법(solid-phase extraction)을 비교 연구하였다. 각 화합물들의 회수율, 상대표준편차 및 검출한계 등을 측정하여 EPA 분석법을 대체할 수 있는지의 가능성을 조사하였다.

• Natural Product Sciences
• /
• 제17권3호
• /
• pp.225-229
• /
• 2011

A new approach for similarity analysis of chemical profiles of Scrophularia buergeriana was developed. The roots of S. buergeriana collected in Andong, Korea were analyzed using HPLC-DAD and the peak areas of the chromatograms were used to construct the chemical profiles of S. buergeriana. The analytical conditions were validated for specificity, precision and repeatability. The standard chemical profiles were established from the chromatograms of nine standard analytical extracts from three batches. The correlation coefficients of peak areas of characteristic compounds between the chromatograms of the standard and test samples were calculated for quantitative expression of the chemical profiles. The results showed that the HPLC chemical profiles of the samples of same geographic origin were relatively consistent. This new approach could be applied to the quality assessment of herbal medicines with complex chemical compositions.

• Advances in nano research
• /
• 제10권1호
• /
• pp.71-76
• /
• 2021

Synthesis of nanoparticles using green technology using plants is gaining significant attention as it is an environmentally friendly substitute to conventional physical and chemical methods. The present study was focused on the chemical and green synthesis of Iron Oxide nanoparticles from ferric chloride. The green synthesis was achieved by utilizing the bio components of Hibiscus rosa-sinensis. The Fe3O4 nanoparticles with the size range of 87-400 nm were synthesized by wet chemical reduction technique which are unstable, prone to aggregation while in green synthesis the phytochemicals present in the leaf extract acts as the capping as well as the reducing agent thus the green synthesized iron (III) oxide nanoparticles were naturally stabilized, spherical shaped and are in the size range of 2-80 nm. The results of both the protocols are compared and presented briefly.

• Korean Chemical Engineering Research
• /
• 제46권2호
• /
• pp.383-388
• /
• 2008

화학공정의 안전하고 효율적인 운전에 관심이 커지면서 공정이상의 원인을 조기에 진단하기 위한 다양한 이상진단방법이 연구되어 왔다. 최근에는 통계적 모델 등 정량적 데이터에 기반한 이상진단방법이 많이 연구되고 있으나, 특정 조업영역에서 얻어진 통계적 모델을 다른 조업영역에 적용하면 오진단이 많아지게 된다. 따라서 공정특성상 다양한 조업영역이 존재하는 화학공정에 데이터기반 방법론을 적용하기에는 어려움이 있어 화학공정의 조업영역 판별법이 요구되고 있다. 이 연구에서는 유클리드 거리(Euclidean distance), FDA(Fisher's discriminant analysis), PCA(principal component analysis)의 통계모델과 이 모델들에 공정변수의 동특성을 반영한 모델을 제안하였다. 6개의 조업모드를 가진 TE(tennessee eastman) 공정에 대한 사례연구를 통해 동특성을 반영한 PCA 모델의 성능이 가장 우수함을 확인하였다.

• 한국환경보건학회지
• /
• 제43권5호
• /
• pp.431-437
• /
• 2017

Objectives: To protect the health and safety of residents during chemical accidents, the governmental authorities need to provide personal protective equipment (PPE) to citizens who desire it. This study aims to investigate residents'awareness of PPE and perform an economic analysis on providing PPE to residents near chemical plants prior to the establishment of a related law. Methods: This study was carried out through a questionnaire completed by 600 residents composed of items such as residents'awareness of PPE, what type of PPE they need, and how to purchase PPE. Economic analysis (cost-benefit analysis) was conducted on providing PPE to residents near chemical plants on basis of the Gumi City hydrogen fluoride accident of 2012. Results: The results of the questionnaire showed that most residents recognized the need for PPE preparedness for chemical accidents, in particular, for respirators. The level of expense that respondents were prepared to shoulder to share the burden was $25. Except for chemicals of hazard level 2, the benefit of all kinds of chemical accident preparedness considerably exceeded costs in the cost-benefit analysis on providing PPE. An estimated government budget of $20 million per year would be required to provide PPE (hood-type mask) for all residents within a one-kilometer radius of chemical plants in Korea, but only $5.8 million when residents share the expenses. Conclusion: The results of this study suggest that programs for providing PPE for residents near chemical plants should be established by law.

• 분석과학
• /
• 제23권6호
• /
• 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.

• 분석과학
• /
• 제14권6호
• /
• pp.535-539
• /
• 2001

One-dimensional coordination polymer of cadmium(II) complex, $[Cd(SCN)_2(C_4H_6N_2]_n$, has been prepared and characterized by X-ray single crystallography. Structure analysis reveals that each cadmium(II) atom is six-coordinated in distorted octahedral fashion with $CdS_2N_4$ composition. $CdS_2N_4$ composition contains two S and two N atoms from four thiocyanates and tow N atoms from two 4-methylimidazole ligands. Central cadmium(II) atoms are run in parallel to the a-axis and are doubly bridged with neighboring cadmium(II) atoms by the thiocyanate and isothiocyanate ligands. Thus, this complex has a one-dimensional polymer structure in which the 4-methylimidazole is in the trans conformation.

• 대한안전경영과학회:학술대회논문집
• /
• 대한안전경영과학회 2013년 추계학술대회
• /
• pp.231-241
• /
• 2013

In recent years, accident induced by human error is increasing in the chemical plant. Human error analysis of the chemical plant was conducted on the basis of past accident. Some company called by A for the basis of a chemical accident. Factor analysis of human errors was separated in plant operation and work. Agency's work of occupational safety & health was classified into four types. It is based on the work before, during work, recovery work, and discontinue work. It was still separated work of human error by analysis and then was derived factor and issue. The human error factor and priority for accident prevention in the chemical plant is presented.

• 한국안전학회지
• /
• 제18권2호
• /
• pp.64-72
• /
• 2003

A new reliability assessment methodology is presented and the new method is compared with fault tree analysis. The system is modeled by directed graph at a new methodology, which is composed of nodes and arcs. The directed graph corresponds to the layout of chemical process and is easy to construct. Therefore, the directed graph analysis is applicable to the chemical process that has complex sequence. The example of fault tree analysis and directed graph analysis is given. The directed graph analysis has proved to be a valuable and useful method for the reliability assessment of chemical process.

• 한국화재소방학회:학술대회논문집
• /
• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
• /
• pp.252-259
• /
• 1997

A method to automate hazard analysis of chemical plants is proposed in this paper. The proposed system is composed of three knowledge bases - unit knowledge base, organizational knowledge base and material knowledge base, and three hazard analysis algorithms - deviation, malfunction and accident analysis algorithm. Hazard analysis inference procedure is developed based on the actual hazard analysis procedures and accident development sequence. The proposed algorithm can perform hazard analysis in two methods and represent all conceivable types of accidents using accident analysis algorithm. In addition, it provides intermediate steps in the accident propagation, and enables the analysis result to give a useful information to hazard assessment. The proposed method is successfully demonstrated by being applied to diammonium phosphate manufacturing process. A system to automate hazard analysis is developed by using the suggested method. The developed system is expected to be useful in finding the propagation path of a fault or the cause of a malfunction as it is capable to approach causes of faults and malfunctions simultaneously.