건식벨트형 자력선별에서 자성입자의 궤적모사

김범욱,전호석,박철현 한국자원공학회 2020 한국자원공학회지 Vol.57 No.1

Magnetic separation, which has been widely used in various industries (e.g., mineral and waste treatment) is an important part of mineral processing. In this study, the simulations of particle trajectories and the relationships between the main parameters in a dry belt-type magnetic separation system are presented. The magnetic field strength simulated by finite element analysis depended upon the vertical distance; the maximum strength was formed at a 0.31 m along the x-axis from a permanent magnet. Simulations of particle trajectories were conducted on ferromagnetic (magnetite), paramagnetic (ilmenite), and diamagnetic (quartz) materials, with variable parameters such as magnetic field strength, particle size, and degree of liberation. The simulation results showed that the key factors of magnetic susceptibility and field strength considerably affected the particle trajectory, as compared with particle size and specific gravity. Hence, the minimum magnetic field strength needed to separate magnetite and ilmenite could be obtained by the regression equation 자력선별법은 광물 및 폐기물 등 다양한 산업에서 활용되고 있는 광물처리의 중요한 분야이다. 본 논문에서는 건식벨트형 자력선별시스템에서 입자궤적을 모사하고 자력선별 주요변수간의 관계를 도출하고자 하였다. 자기장 모사는 유한요소해석 프로그램에 의해 수행되었고 주요 영향 변수는 수직이격 거리이었다. 최대 자기장세기는 영구자석로부터 X축의 0.31 m 지점에서 형성되었다. 입자궤적모사는 강자성(자철석), 상자성(티탄철석) 및 반자성(석영) 물질에 대해 자기장세기, 입자크기 및 단체분리도의 조건변화에 따라 수행되었다. 모사결과, 입자크기와 비중에비해 자화율과 자기장세기가 입자궤적에 영향을 미치는 주요 변수임을 확인하였다. 이로부터 자철석과 티탄철석을선별하기 위한 최소 자기장의 세기가 회귀식에 의해 도출되었다.

토양의 물리화학적 특성, 중금속 함량, 대자율 간의 상호관계 연구

전철민 ( Chul Min Chon ),박정식 ( Jeong Sik Park ),김재곤 ( Jae Gon Kim ),이윤수 ( Youn Soo Lee ) 한국광물학회 2010 광물과 암석 (J.Miner.Soc.Korea) Vol.23 No.4

비오염토양, 폐광산 주변토양, 산업단지 주변토양을 채취하여 X-선 회절분석, pH, 전기전도도, 양이 온교환능력, 작열감량, 산화철·산화망간 함량, 중금속 함량 및 중금속 존재형태와 토양대자율의 상관관계를 파악하였다. 시료의 X-선회절분석 정량분석결과 비오염지역 토양에서는 모암에 따라 다양한 광물이 분포하고 있지만, 적철석과 자철석은 거의 관찰되지 않았다. 폐광산 주변토양은 폐광석, 광물찌꺼기 등의 영향으로 적철석이 많이 확인되었고, 일부 시료에서는 자철석도 존재하였다. 산업단지 주변시료에서는 방해석과 철백운석 등의 탄산염 광물들이 대부분의 시료에서 확인되었다. 중금속의 존재형태를 파악하기 위한 연속추출 실험 결과, 폐광산 주변지역 토양시료에서 철, 망간, 중금속 원소들은 reducible, oxidizable, residual 단계별 추출 형태로 80% 이상, 산업단지 주변시료에서는 50% 이상 존재하였다. 산업단지 주변시료의 경우, 탄산염 광물의 영향으로 carbonate 형태가 높게 나타났다. 왕수로 추출된 철, 망간, 비소, 아연 함 량은 산화철/산화망간 형태를 지시하는 dithionite-citrate-bicarbonate (DCB) 용출 함량과 매우 밀접한 정의상관관계를 보여주었다. 철과 비소는 각각 왕수추출함량의 54%, 58%가 산화철/산화망간 형태과 함께 거동하는 것으로 나타났다. 대자율은 0.005∼2.131 × 10(-6) m3 kg-1의 범위로서, 시료 내에 적철석, 자철석 등 산화철 광물이 존재할 경우 대자율이 높게 측정되었다. 토양 내 중금속 함량과 대자율의 상관관계를 살펴본 결과 철(r = 0.608, p < 0.01), 망간(r = 0.615, p < 0.01)과 유의한 정의 상관관계를 보였으며, 카드뮴(r = 0.544, p < 0.05), 크롬(r = 0.714, p < 0.01), 니켈(r = 0.645, p < 0.05), 납(r = 0.703, p < 0.01), 아연(r = 0.496, p < 0.01) 등의 중금속 원소와도 유의한 정의 상관관계를 보였다. 철, 망간 및 중금속원소들 간의 상관관계를 살펴본 결과, 왕수로 용출된 철, 망간 함량과 카드뮴, 크롬, 구리, 니켈, 아연 등의 중금속 함량이 정의 상관관계를 보이고 있다. 또한 산화철 및 산화망간 함량은 비소 및 니켈 함량과 밀접한 상관성이 있는것으로 나타났다. 이는 비소와 니켈은 산화철, 산화망간에 흡착되어 함께 거동함을 암시한다. This paper deals with magnetic susceptibility, mineralogy, soil properties (pH, EC, CEC, loss on ignition), iron and manganese oxides, the content and partitioning of heavy metals (As, Cd, Cr, Cu, Ni, Pb, Zn), and their mutual relationship in the soil samples of an unpolluted, abandoned mine area, and industrial complex area. The various minerals derived from weathered bedrock were identified by X-ray diffraction in the unpolluted soil samples, except for the magnetic minerals. XRD analysis also revealed the existence of hematite and magnetite related to mine tailings and waste rocks in the abandoned mine area samples. The industrial complex area samples had carbonate minerals, such as calcite and dolomite, that might be due to anthropogenic deposition. The sum of the reducible, oxidizable, and residual fractions was over 80% for the abandoned mine area samples and over 50% for the industrial complex area samples using the sequential extraction method. The industrial complex area samples had a relatively high carbonate fraction that was associated with carbonate minerals. The content of aqua regia-extractable Fe, Mn, As, and Zn had a high positive correlation with the content of the dithionite-citrate-bicarbonate (DCB)-extractable method related to Fe/Mn oxide phases. The 54% and 58% of aqua regia-extractable Fe and As content, respectively, acted together with the concentrations of the DCB-extractable phases. Magnetic susceptibility values of total samples ranged from 0.005 to 2.131 × 10(-6) m3kg-1. The samples including iron oxide minerals, such as hematite and magnetite, had a high magnetic susceptibility. The magnetic susceptibility showed a significant correlation with the heavy metals, Cd (r = 0.544, p < 0.05), Cr (r = 0.714, p < 0.01), Ni (r = 0.645, p < 0.05), Pb (r = 0.703, p < 0.01), and Zn (r = 0.496, p < 0.01), as well as Fe (r = 0.608, p < 0.01) and Mn (r = 0.615, p < 0.01). The aqua regia-extractable Fe and Mn content had a significant positive correlation with Cd, Cr, Cu, Ni, and Zn. However, the DCB-extractable Fe and Mn content had a significant positive correlation with As and Ni, indicating that the heavy metals were associated with Fe and Mn oxide minerals.

Findings Regarding an Intracranial Hemorrhage on the Phase Image of a Susceptibility-Weighted Image (SWI), According to the Stage, Location, and Size

이윤정,이송,장진희,최현석,정소령,안국진,김범수,이강훈 대한자기공명의과학회 2015 Investigative Magnetic Resonance Imaging Vol.19 No.2

Purpose: Susceptibility weighted imaging (SWI) is a new magnetic resonancetechnique that can exploit the magnetic susceptibility differences of various tissues. Intracranial hemorrhage (ICH) looks a dark blooming on the magnitude images ofSWI. However, the pattern of ICH on phase images is not well known. The purpose ofthis study is to characterize hemorrhagic lesions on the phase images of SWI. Materials and Methods: We retrospectively enrolled patients with ICH, whounderwent both SWI and precontrast CT, between 2012 and 2013 (n = 95). AnSWI was taken, using the 3-tesla system. A phase map was generated after postprocessing. Cases with an intracranial hemorrhage were reviewed by an experiencedneuroradiologist and a trainee radiologist, with 10 years and 3 years of experience,respectively. The types and stages of the hemorrhages were determined in correlationwith the precontrast CT, the T1- and T2-weighted images, and the FLAIR images. Thesize of the hemorrhage was measured by a one- directional axis on a magnitude imageof SWI. The phase values of the ICH were qualitatively evaluated: hypo-, iso-, andhyper-intensity. We summarized the imaging features of the intracranial hemorrhageon the phase map of the SWI. Results: Four types of hemorrhage are observed: subdural and epidural; subarachnoid;parenchymal hemorrhage; and microbleed. The stages of the ICH were classifiedinto 4 groups: acute (n = 34); early subacute (n = 11); late subacute (n = 15);chronic (n = 8); stage-unknown microbleeds (n = 27). The acute and early subacutehemorrhage showed heterogeneous mixed hyper-, iso-, and hypo-signal intensity;the late subacute hemorrhage showed homogeneous hyper-intensity, and the chronichemorrhage showed a shrunken iso-signal intensity with the hyper-signal rim. Allacute subarachnoid hemorrhages showed a homogeneous hyper-signal intensity. Allparenchymal hemorrhages (> 3 mm) showed a dipole artifact on the phase images;however, microbleeds of less than 3 mm showed no dipole artifact. Larger hematomasshowed a heterogeneous mixture of hyper-, iso-, and hypo-signal intensities. Conclusion: The pattern of the phase value of the SWI showed difference, accordingto the type, stage, and size.

Findings Regarding an Intracranial Hemorrhage on the Phase Image of a Susceptibility-Weighted Image (SWI), According to the Stage, Location, and Size

Lee, Yoon Jung,Lee, Song,Jang, Jinhee,Choi, Hyun Seok,Jung, So Lyung,Ahn, Kook-Jin,Kim, Bum-soo,Lee, Kang Hoon Korean Society of Magnetic Resonance in Medicine 2015 Investigative Magnetic Resonance Imaging Vol.19 No.2

Purpose: Susceptibility weighted imaging (SWI) is a new magnetic resonance technique that can exploit the magnetic susceptibility differences of various tissues. Intracranial hemorrhage (ICH) looks a dark blooming on the magnitude images of SWI. However, the pattern of ICH on phase images is not well known. The purpose of this study is to characterize hemorrhagic lesions on the phase images of SWI. Materials and Methods: We retrospectively enrolled patients with ICH, who underwent both SWI and precontrast CT, between 2012 and 2013 (n = 95). An SWI was taken, using the 3-tesla system. A phase map was generated after postprocessing. Cases with an intracranial hemorrhage were reviewed by an experienced neuroradiologist and a trainee radiologist, with 10 years and 3 years of experience, respectively. The types and stages of the hemorrhages were determined in correlation with the precontrast CT, the T1- and T2-weighted images, and the FLAIR images. The size of the hemorrhage was measured by a one- directional axis on a magnitude image of SWI. The phase values of the ICH were qualitatively evaluated: hypo-, iso-, and hyper-intensity. We summarized the imaging features of the intracranial hemorrhage on the phase map of the SWI. Results: Four types of hemorrhage are observed: subdural and epidural; subarachnoid; parenchymal hemorrhage; and microbleed. The stages of the ICH were classified into 4 groups: acute (n = 34); early subacute (n = 11); late subacute (n = 15); chronic (n = 8); stage-unknown microbleeds (n = 27). The acute and early subacute hemorrhage showed heterogeneous mixed hyper-, iso-, and hypo-signal intensity; the late subacute hemorrhage showed homogeneous hyper-intensity, and the chronic hemorrhage showed a shrunken iso-signal intensity with the hyper-signal rim. All acute subarachnoid hemorrhages showed a homogeneous hyper-signal intensity. All parenchymal hemorrhages (> 3 mm) showed a dipole artifact on the phase images; however, microbleeds of less than 3 mm showed no dipole artifact. Larger hematomas showed a heterogeneous mixture of hyper-, iso-, and hypo-signal intensities. Conclusion: The pattern of the phase value of the SWI showed difference, according to the type, stage, and size.

Relationship between Abnormal Hyperintensity on T2-Weighted Images Around Developmental Venous Anomalies and Magnetic Susceptibility of Their Collecting Veins: In-Vivo Quantitative Susceptibility Mapping Study

Yangsean Choi,장진희,Yoonho Nam,Na-Young Shin,Hyun Seok Choi,정소령,안국진,김범수 대한영상의학회 2019 Korean Journal of Radiology Vol.20 No.4

Objective: A developmental venous anomaly (DVA) is a vascular malformation of ambiguous clinical significance. We aimed to quantify the susceptibility of draining veins (χvein) in DVA and determine its significance with respect to oxygen metabolism using quantitative susceptibility mapping (QSM). Materials and Methods: Brain magnetic resonance imaging of 27 consecutive patients with incidentally detected DVAs were retrospectively reviewed. Based on the presence of abnormal hyperintensity on T2-weighted images (T2WI) in the brain parenchyma adjacent to DVA, the patients were grouped into edema (E+, n = 9) and non-edema (E-, n = 18) groups. A 3T MR scanner was used to obtain fully flow-compensated gradient echo images for susceptibility-weighted imaging with source images used for QSM processing. The χvein was measured semi-automatically using QSM. The normalized χvein was also estimated. Clinical and MR measurements were compared between the E+ and E- groups using Student’s t-test or Mann-Whitney U test. Correlations between the χvein and area of hyperintensity on T2WI and between χvein and diameter of the collecting veins were assessed. The correlation coefficient was also calculated using normalized veins. Results: The DVAs of the E+ group had significantly higher χvein (196.5 ± 27.9 vs. 167.7 ± 33.6, p = 0.036) and larger diameter of the draining veins (p = 0.006), and patients were older (p = 0.006) than those in the E- group. The χvein was also linearly correlated with the hyperintense area on T2WI (r = 0.633, 95% confidence interval 0.333–0.817, p < 0.001). Conclusion: DVAs with abnormal hyperintensity on T2WI have higher susceptibility values for draining veins, indicating an increased oxygen extraction fraction that might be associated with venous congestion.

금속 생체재료를 위한 Sn 함량에 따른 Zr-7Cu 합금설계

김민석,김정석 한국재료학회 2021 한국재료학회지 Vol.31 No.12

The purpose of this study is to develop a zirconium-based alloy with low modulus and magnetic susceptibility to prevent the stress-shielding effect and the generation of artifacts. Zr-7Cu-xSn (x = 1, 5, 10, 15 mass%) alloys are prepared by an arc melting process. Microstructure characterization is performed by microscopy and X-ray diffraction. Mechanical properties are evaluated using micro Vickers hardness and compression test. The magnetic susceptibility is evaluated using a SQUIDVSM. The average magnetic susceptibility value of the Zr-7Cu-xSn alloy is 1.176 × 108 cm3g1. Corrosion tests of zirconiumbased alloys are conducted through polarization test. The average Icorr value of the Zr-7Cu-xSn alloy is 0.1912 A/cm2. The elastic modulus value of 14 ~ 18 GPa of the zirconium-based alloy is very similar to the elastic modulus value of 15 ~ 30 GPa of the human bone. Consequently, the Sn added zirconium alloy, Zr-7Cu-xSn, is very interesting and attractive as a biomaterial that reduces the stress-shielding effect caused by differences of elastic modulus between human bone and metallic implants. In addition, this material has the potential to be used in metallic dental implants to effectively eliminate artifacts in MRI images due to low magnetic susceptibility.

직장암의 평가를 위한 자기공명 확산강조영상에서 장내 공기에 의한 국소자화율의 차이가 현성확산계수에 미치는 영향 평가

강성진(Sung-Jin Kang) 한국자기학회 2019 韓國磁氣學會誌 Vol.29 No.6

This study was to assess the effect of the variation in the magnetic susceptibility by intra-luminal air of rectum for quantification of ADC values. For this study, Fifty patients with before treatment rectal adenocarcinoma were selected. All patients were scanned MRI using by DWI technique before and after rectal lumen filling obtained using sonographic transmission gel. Also, DWI was imaged by applying B values of 50 and 1,000 respectively. In both DWI, two blinded observers measured ADC values on regions of interest respectively intra tumor tissue. Correlation and Intra-observer agreement verification from measured ADC value by observers were compared using Paired T-test and Intra-class correlation coefficient. As a result, Both observers measurements ADC value increased after gel injection. In the result of paired T-test, both observers showed statistically significant changes in measured ADC values before and after gel injection (p < 0.05). In addition, In the result of ICC the agreement between observers was statistically significant (p < 0.05). In conclusion, it was confirmed that the difference in magnetic susceptibility by air in the rectum may influence the quantitative evaluation of ADC value. Therefore, When evaluating the state of rectal cancer using the ADC values, it is necessary to consider the change of ADC value by magnetic susceptibility.

전북 완주군 봉동 하안단구 상부 뢰스-고토양 연속층의 풍화특성과 기원지

황상일(Sangill Hwang),박충선(Chung-Sun Park),윤순옥(Soon-Ock Yoon) 대한지리학회 2009 대한지리학회지 Vol.44 No.4

전라북도 완주군 봉동읍에 위치한 만경강 하안단구 역층 상부에 퇴적되어 있는 뢰스-고토양 연속층을 대상으로 토양분석과 대자율 측정, 입도 및 원소분석을 행하여 퇴적물의 풍화 특성과 기원지를 검토하였다. 봉동단면은 상부에서 하부로 Layer 1(고토양), Layer 2(뢰스), Layer 3(고토양) 그리고 하안단구 역층으로 이루어진다. 대자율은 뢰스층과 고토양층 사이에 뚜렷한 차이를 보이며, 입도분석 결과는 봉동단면이 하천이나 사면이동이 아니라 바람에 의해 운반되었으며, 중국 뢰스고원이나 대천뢰스보다 상당히 세립질임을 보여준다. 토양분석 중 유기물 함량만이 대자율과 유사한 변화를 보이며, 건조 토색보다는 습윤 토색이 뢰스-고토양 연속층의 특성을 보다 잘 반영한다. 주원소 및 희토류 원소 분석 결과, 봉동단면의 뢰스물질은 중국 뢰스고원과 동일한 기원지 또는 재이동된 물질에 의해 형성되었으며, 퇴적 이후에는 고온다습한 우리나라 기후 환경에서 중국 뢰스고원보다 심하게 풍화작용을 받았다. The weathering properties and provenance of loess-paleosol sequence deposited on gravel layer of river terrace in Bongdong-eup, Wangju-gun, Jeonbuk Province are examined using soil analysis, magnetic susceptibility measurement, grain size and element analysis. The Bongdong section consists of, from top to bottom, Layer 1(paleosol), Layer 2(loess), Layer 3(paleosol) and the gravel layer of river terrace. The magnetic susceptibility values show the systematic variations in the sequence and the results of grain size analysis reveal that the sequence was deposited by not fluvial or slope process, but eolian process, and that contains finer materials than the Daecheon loess and Chinese Loess Plateau. Among the results of soil analysis, organic contents indicate systematic variations similar to the magnetic susceptibility. The wet soil colors further reflect the characteristics of the sequence rather than the dry soil colors. Based on the analytical results of major and rare earth elements, the eolian materials contained in the sequence were deposited by the materials originated from the areas where the Chinese Loess Plateau has been originated or the reworked materials from the Chinese Loess Plateau, and after the depositions, the materials experienced the intensive chemical weathering under the humid-warm climatic conditions in the Korean Peninsula.

충남 부여지역의 홀로세 기후변화 : 탄소동위원소분석과 대자율분석을 이용하여

박경(Kyeong Park),박지훈(Ji-Hoon Park) 대한지리학회 2011 대한지리학회지 Vol.46 No.4

충남 부여지역의 홀로세(약 8,400 yrs B.P.~현재) 기간의 환경 특히 기후환경을 복원하기 위하여 부여군 가탑리 일대에 분포 하는 선상지 퇴적물을 대상으로 탄소동위원소분석과 대자율분석을 실시하였다. 탄소동위원소분석 결과에 의하면, 조사지역에서는 크게 5회의 기후변화가 확인되었는데 Ⅰ期부터 Ⅵ期로 가면서 가장 냉량 건조→ 온난 습윤 → 냉량 건조 → 온난 습윤 → Ⅳ期에 비해 건조 → Ⅴ期에 비해 습윤한 환경으로 변천하는 것을 알 수 있었다. 특히 약 5,900~3,200 yrs B.P.의 기간이 상대적으로 가장 온 난·습윤했던 것으로 밝혀졌다. 하지만 대자율분석에 의하면 시료채취지점 일대의 환경변화는 크게 4개의 시대로 구분되는데 ii-期에 가장 대자율이 높다. Ⅰ-期는 배후습지 기원의 퇴적물로 이루어져 있으며, 시간의 경과에 따라 토양화가 진전되었다. 이에 비해 ii- 期와 iii-期에서 대자율이 다른 시기에 비해 높은 이유는 구릉사면의 풍화와 토양화 과정에서 강자성 광물이 집적된 토양층이 침식에 의해 제거되고 이들이 운반되어 선상지 퇴적물을 형성했기 때문이다. ⅳ-期는 경작층으로 이용되는 현재에 대비된다. Multi-proxy analysis was used to produce a high-resolution paleoclimatic record from a thick section of the Holocene alluvial fan deposit in Gatap-ri, Buyeo. According to δ¹³C analyses, five minor climate fluctuations can be determined. From the stage I to stage Ⅵ, climate changes are as follows: cool-dry, warm-humid, cool-dry, warm humid, drier than stage Ⅳ, and finally more humid environment than stage Ⅴ. According to magnetic susceptibility records, four different stages can be identified, among which stage ii shows the highest susceptibility. Stage-i deposit is derived from sediments of back marsh-type wetland. Stage-ii and stage-iii deposits, however, show higher magnetic susceptibility because magnetite-enriched soil from weathered upland was transported to the area to form an alluvial fan deposits. Stage-iv deposit is comparable to the modern plow horizon.

광물성 한약으로 이용되는 양기석, 연옥, 음기석의 분광학적 및 자기적 특성

김선옥,박맹언,정율필 대한자원환경지질학회 2002 자원환경지질 Vol.35 No.4

양기와 음기를 보하는 약재로 알려진 양기석과 음기석 및 연옥에 대한 의료적 활용을 파악하고, 광물학적 특성, 분광학적 및 자기적 특성을 규명하기 위하여 X선 형광분석, X-선 회절분석, 주사전자현미경, 적외선 분광분석, 핵자기 공명분석 및 감응자기력을 실시하였다. 광물성 한약으로 사용되는 양기석은 양기석으로 확인되었으뗘, 연옥은 투각섬석으로 구성되었다. 또한, 음기석은 주로 질석으로 구성되며, 소량의 카올리나이트와 할로이사이트를 함유하였다. 사슬형 규산염 중 각섬석군에 속하는 이들 연옥과 양기석은 유사한 범위의 분광학적 특성을 가지며, 연옥은 40℃에서 방사에너지가 큰 반면, 양기석은 150℃에서 방사에너지가 크다 음기석은 각섬석군의 광물보다 40℃와 150℃에서 모두 낮은 방사에너지를 나타내었다. 광물성 한약을 증류수에 20일간 침적한 후에 측정한 NMR분석에서의 선폭은 음기석, 양기석, 연옥의 순으로 감소되나, 80일이 경과한 후의 결과는 음기석, 연옥, 양기석 순으로 감소하였다. 양기석과 음기석은 가열 온도가 높아짐에 따라 감응 자기력 값이 대체적으로 증가하고, 연옥은 감소하는 경향을 나타내었다. 광물별로는 상온과 가열시 모두 음기석, 양기석, 연옥의 순으로 감소하였다. Mineral medicines are single or mixtures of minerals and rocks which have been used to treat disease. Recently, their application has been increased by emphasizing the physical properies of the medicines, in addition to their chemical properies. In this study, mineralogical, chemical, spectroscopic and magnetic properties were measured using X-ray diffraction analysis, X-ray fluorescence spectrometry, FT-Infrared spectroscopy, nuclear magnetic resonance spectroscopy, mass magnetic susceptibility. Experiments were done using these properties to evaluate application of traditional mineral medicines such as Yanggiseok, Yeonok and Eumgiseok. Mineralogical study proves that Yanggiseok, generally known as tremolite, consists of actinolite. Yeonok for medical usage mostly consists of fine grained tremolite. Eumgiseok is mainly composed of vermiculite and minor kaolinite and halloysite. Yeonok and Yanggiseok, belong to the amphibole group among inosilicates and both have similar emission power properties. The intensity of emission power, calculated from FT-IR measurements, follows in the order of Yeonok, Yanggiseok and Eumgiseok at 40℃ and Yanggiseok, Yeonok and Eumgiseok in such order at 150℃. As a result of NMR analysis after 20 days in distilled water, the three mineral medicines decreased in the following order; Eumgiseok, Yanggiseok and Yeonok. However, the same minerals decreased in the order of Eumgiseok, Yeonok and Yanggiseok after 80 days. In response temperature, magnetic susceptibility of Yanggiseok and Eumgiseok systematically increased by heating to 25℃, 100℃ and 700℃. Magnetic susceptibility of Yeonok shows a decreasing pattern due to heating.