Analysis of Mobile Lead in Soil Using Carboxylated Magnetic Particle

Hyungsuk So,Hyun Chul Shin,Yeong-Seok Yoo,Andreas Schaeffer 한국자기학회 2005 Journal of Magnetics Vol.10 No.3

The analytic possibility of mobile lead contained in soil has been studied using carboxylated magnetic beads. Extraction of heavy metal was performed to contaminated soil that has been collected and supplied for tests. As experiment materials, soil sample, distilled water and magnetic beads were only used. It means that the lead was extracted under neutral condition. In this condition, only the mobile fraction of lead could be extracted by magnetic beads. The mobile lead in the soil was quickly combined with magnetic beads in the mixture process. Then, the magnetic beads were dissolved into acids after collection by external magnetic force, and the lead combined with the beads was eluted and analyzed by Graphite Furnace Atomic Absorption Spectroscopy (GFAAS). In the results of extraction experiments for 3 sandy soils, the efficiency using beads was similar to or higher than that of EDTA (Ethylendiamintetraacetic acid), which is normally used for analyzing mobile heavy metal concentration in soil. With this, it was shown that this method is a more accurate and simple method to analyze mobile lead when analyzing mobile heavy metal concentration in sandy soil, rather than conventional method using EDTA.

Availability of Carboxylated Magnetic Beads for Extracting Heavy Metals from Aqueous Solution

Hyungsuk So,Yeong-Seok Yoo,Andreas Schaeffer 한국자기학회 2006 Journal of Magnetics Vol.11 No.2

It was examined in this study that magnetic beads, which are assumed to be environmentally functional, could be effective in processing heavy metals that are water pollutants. For the purpose, magnetic beads containing carboxyl groups, which has strong binding force with heavy metals, are mixed with each Cd, Pb, Ni, Cu and Cr(III) solution, then stirred in pH 6. As a results of the process, it was proven that heavy metals bind quickly with magnetic beads through the reaction. In order to analyze heavy metal concentration, magnetic beads bind with heavy metal were collected by external magnetic force and dissolved in acid. The graphite furnace AAS was used to get heavy metal concentration melted in the acid solution. The results showed that heavy metal extractions by magnetic beads were influenced by the type and the concentration of a heavy metal, and over 90% of a heavy metal can be extracted in ppm level save for Cr(III). It was also examined in the study whether heavy metal extraction is influenced when other ions exist in each heavy metal solution. According to experiment, adding other heavy metals to a solution did have little influence on extracting an intended heavy metal. But in case salt or heavy metal chelate was added, Ni extraction changed sensitively although extracting other heavy metals were influenced only when the concentration of an added substance is high. In conclusion, it was shown that magnetic beads could be used to treat wastewater with relatively high heavy metal concentration.

자력을 이용한 토양입자와 마이크로자성체의 분리 연구

서형석(Hyungsuk So),신현철(Hyun Chul Shin),유영석(Yeong-Seok Yoo) 한국자기학회 2005 韓國磁氣學會誌 Vol.15 No.2

It was evaluated whether magnetic beads able to add the functionality of environment purification can be employed in processing soil pollutants. In this study, the micro scale magnetic beads containing carboxyl groups were mixed with water and the soil (<0.025 ㎜) filtered through a sieve, and then it was agitated before isolating the magnetic substances by the use of outer magnetic force. The factors considered at this step were the ratio of soil to magnetic beads, ratio of soil to water, size of the tube where the reaction occur, and intensity of the magnetic force. From the separation experiment between soil and magnetic beads, it was concluded that the magnetic beads and water quantity have an impact on the degree of separation, yet the size of the tube and magnetic force does not have a considerable effect upon that in this small-scaled experiment. Through this experiment, the reaction conditions were optimized to achieve 90~100% of separation. Therefore, it was concluded that when the functionalized magnetic beads is introduced to environmental processing, it is able to be adopted to the soil processing as well as the water processing.

A Case with Multiple Fungal Coinfections in a Patient who Presented with Pancoast Syndrome

( Hyungsuk Jin ),( Dongsub Kim ),( Joon-sik Choi ),( Hee Jae Huh ),( Nam Yong Lee ),( Joungho Han ),( Hee Won Cho ),( Youngeun Ma ),( Tae Yeon Jeon ),( So-young Yoo ),( Keon Hee Yoo ),( Hong Hoe Koo ) 대한소아감염학회 2021 Pediatric Infection and Vaccine Vol.28 No.1

소아암 환자에서 발생하는 침습성 진균 감염은 사망과 후유증에 이르는 중대한 감염이다. 18세 남자 환자가 호중구감소 기간 동안 입원하여 치료받던 중 우측 견관절과 우측 팔에 감각이상과 신경쇠약을 호소하였고, 우측폐상엽의 폐렴이 진단되었다. 기관지의 조직학적 소견과 폐 수술검체에서 시행한 polymerase chain reaction (PCR)로 털곰팡이증을 확진하였으며, 흉수액의 PCR로 페니실리움 디쿰벤스 감염, 갈락토마난 항원법으로 아스페르길루스증을 추정하였다. 환자는 백혈병이 치료되지 못하고 Staphylococcus epidermidis 패혈증이 합병되어 사망하였다. 본 증례에서는 판코스트 증후군의 증상을 보인 환자에서 진단된 다발성 폐진균증을 보고 하는 바이다. Invasive fungal infection (IFI) is a serious threat to pediatric patients with cancer given high morbidity and mortality. We present an 18-year-old male with precursor T-cell lymphoblastic leukemia who developed Pancoast syndrome, presented with paresthesia and numbness in the right shoulder and arm during a neutropenic fever period. He was diagnosed with pneumonia in the right upper lung field. He was later found to have an invasive pulmonary fungal infection caused by multiple fungi species, including Rhizomucor, confirmed by histology and polymerase chain reaction (PCR) (proven infection), Penicillium decumbens diagnosed by PCR, and Aspergillus suspected from galactomannan assay (probable infection). Unfortunately, the patient's condition further worsened owing to the aggravation of leukemia, chemotherapy-induced neutropenia, and bacterial coinfection, leading to multiorgan failure and death. Here, we report a case of IFI caused by multiple fungal species that presented as Pancoast syndrome.

기능성 자성입자를 이용할 토양의 유동성 카드뮴 분석

서형석,나인욱,황경엽,신현철,김범석,유영석,So Hyungsuk,Nah In-Wook,Hwang Kyung-Yub,Shin Hyun Chul,Kim Beom-Suk,Yoo Yeong-Seok 한국지하수토양환경학회 2005 지하수토양환경 Vol.10 No.1

Potential for measuring mobile cadmium concentration in sandy soil using polymer magnetic beads with carboxyl groups was investigated. Experiments for extracting cadmium were performed with contaminated soils, de-ionized water and magnetic beads. In this neutral experimental condition, reacting cadmium with magnetic beads indicate total amount of cadmium that can be moved in soil. The results showed that the mobile fraction of cadmium in soil could be combined with magnetic beads in short time. After binding between cadmium and magnetic beads, the beads were separated from soil suspension by outer magnetic force. The bound cadmium was dissolved from magnetic beads by acid solutions, which were then analyzed by atomic absorption spectroscopy (AAS). This method can determine mobile heavy metals in sandy soil effectively than existing method which use pollutant chemicals to environments such as EDTA. 카르복실기가 결합된 고분자 자성체 (Magnetic beads)를 이용하여 토양에 함유되어 있는 유동성 카드뮴의 분석 가능성을 알아보았다. 추출실험은 채취된 오염토양을 통하여 행하여 졌는데, 추출실험재료로는 단지 토양시료, 증류수 그리고 고분자 자성체만이 사용되었다. pH가 중성인 이 조건에서 자성체는 토양에서 이동성이 있는 카드뮴만을 추출하게 되는데, 이런 토양의 유동성 카드뮴이 교반을 통하여 빠르게 고분자 자성체와 결합하는 것을 알아냈다. 그 후 자성체는 외부 자력으로 모아져 산으로 용해되고, 자성체에 결합되어 있던 카드뮴 다시 용출되어 Graphite furnace 원자흡광기 (AAS)로 분석되었다. 3가지 모래성토양의 추출실험결과를 보면 토양의 유동성 중금속 농도를 분석할 때 전형적으로 사용하는 EDTA (Ethylendiamintetraacetic acid)와 비교할 때, 고분자 자성체를 이용한 효율이 비슷하거나 더 높았음을 알 수 있었다. 이로서 모래성토양에서 유동성 중금속 농도를 분석할 때, 난분해성 물질인 EDTA등을 사용하지 않고 더 정확하고 간단히 유동성 카드뮴의 분석실험을 수행할 수 있음을 보여주었다.

상변화 보드 설계 변수의 축열성능에의 영향 연구

구준모(Junemo Koo),홍희기(Hiki Hong),서형식(Hyungsuk So) 대한설비공학회 2009 대한설비공학회 학술발표대회논문집 Vol.2009 No.-

The effects of the temperature difference between the average room- and phase change (PCM) meterial phase changing temperatures, and the duration of its phase change on the stored energy and the temperature profile time shift are investigated. The optimal thickness of PCM board is presented based on the simulation results.