Graves 병과 혈청 면역글로불린-E의 연관성

김현영,박기룡,김성훈,김지연,송수근,최영식,박요한 대한내분비학회 2002 Endocrinology and metabolism Vol.17 No.5

연구배경: Graves 병은 미만성 갑상선종, 갑상선기능한진, 안구침법 등을 특징으로 하는 자가면역성 질환으로, 갑상선자극호르몬 수용체에 대한 자가항체(TRAb)가 갑상선을 자극하여 발생된다. TRAb는 Graves병 환자의 약 85%이상에서 검출되며 활성화된 TRAb는 대부분 IgE로 알려져 있다. 그러나 최근 Graves병 환자의 갑상선조직과 안구조직에 IgE의 침착과 꽃가루 등에 의한 알레르기성 비염으로 인해 Graves병이 발생하거나 재발된 견우가 보고되어 Graves병의 병인에 IgE의 연관성이 제기 되고 있으나, 국내에서는 이에 대한 연구가 드물다. 본 연구에서는 Graves병에서의 혈청 IgE농도와 Graves병의 병기와의 관계 및 TRAb와 IgE 농도와의 연관성을 살펴보고자 하였다. 대상 및 방법 : 2000년 4월 1일부터 7월 1일까지 고신의료원 내분비내과를 방문한 환자 중 Graves병 46예, 만성갑상선염 6예 및 고신의료원 건강증진센터를 방문한 환자 중 갑상선질환의 병력이나 가족력 및 알레르기성 비염의 병력이 없는 35예의 정상대조군을 대상으로 연구를 시행하였다. TRAb는 갑상선자극호르몬 결합 억제 면역글로불린(TBII)으로 측정하였으며, IgE는 효소면역분석법으로 측정하였다. 결과: IgG인 TBII는 Graves병에서 만성갑상선염과 대조군에 비해 높았으며, IgE 평균농도는 Graves병에서 598.1±1112.9U/mL로 만성갑상선염 환자의 98350±79.7U/mL, 대조군 161.72±194.4U/mL에 비해 높았다(p<0.05). Graves병에서 알레르기성 비염의 발병율은 10.9%(5/46)였으며, Graves 병에서의 혈청 IgE 농도는 알레르기성 비염의 병력이 있는 경우 903.1±1152.2U/mL로 없는 경우 560.8±1117.0U/mL보다 높은 경향을 보였다. Graves병의 병기에 따른 TBII와 IgE 농도의 변화를 항갑상선제로 치료하지 않은 군(비치료군)과 치료한 군(치료군) 및 재발군으로 나누어 비교하였을 때, TBII는 치료군(7.4±18.6%)에 비해 비치료군(49.9±23.9%)과 재발군(21.1±3.1%)에서 높았으며(p<0.05), 혈청 IgE치도 치료군(233.8±432.7U/mL)에 비해 비치료군(758.6±1250.0U/mL)과 재발군(1198.5±1952.1U/mL)에서 높은 경향을 보였다. 항갑상선제로 치료한 치료기간에 따른 TBII와 IgE 농도 변화에서, TBII는 비치료군(49.9±23.9%)과 1년 미만 치료군(24.8±3.8%)에서 1년 이상 치료군(2.22±1.97%)에 비해 높았으며(p<0.05), 혈청 IgE 농도는 비치료군(758.6±1250.2U/mL)에서 1년 미만 치료한 군(158.3±91.5U/mL)과 1년 이상 치료군(252.7±483.4U/mL)에 비해 높았으나 유의하지는 않았다. 결론: Graves 병에서 IgE 농도는 증가되어 있었으며, Graves 병의 각각 다른 병기에서의 혈청 IgE 농도의 변화는 Graves qudd의 경과에 영향을 미치는 IgG인 TBII치의 변화와 유사한 경향을 보였다. 그러나 혈청 IgE와 Graves 병과의 연관성을 알아보기 위해서 IgE와 더불어 CD23항원 등의 다른 검사도 병행하는 전향적 연구가 필요할 것으로 생각된다. Background: It is widely believed that Graves' disease is and autoimmune disorder characterized by the presence of the circulation TSH receptor antibody (TRAb). The majority of the activity of TRAb is of the immunoglobulin G(IgG) class. However, other immunoglobulin such as immunoglobulin E(IgE), may play a rloe in the activity. IgE accumulation has been reported to occur in the thyroid gland and ocular muscles of subjects with Graves' disease. Furthermore, it has been noted that recurrence of Graves' disease can be induced by and allergy to pollen. Because an allergy to pollen is commonly associated with IgE, IgE might play a role in the induction of Graves' disease. Therefore, investigated whether IgE was elevated in Graves' disease, and evaluated the potential relationship between the levels of TRAb and IgE Graves' disease. Methods: Forty-six patients with Graves' disease, and 6 with chronic thyroiditis, diagnosed at the Kosin Medical Center between April, 2000 and July, 2000 were included in this study. Thirty-five persons without thyroid disease or a history of allergic rhinitis were used as normal controls. The level or TRAb was measured using thyrotropin binding inhibitory immunoglobulin (TBII). Serum total IgE was measured using as enzymeimmunoassay method. Test for thyroid function, TBII and total IgE were performed in all cases, and the results statistically analyzed. Results: TBII, as IgG, and the serum IgE level were higher in the patients with Graves' disease, and the levels of the latter were 598.1±1112.9U/mL, 98.5±79.7U/mL and controls 161.7±194.4U/mL in the Graves' patients, those with thyroiditis and the controls, respectively (p<0.05). The prevalence of allergic rhinitis in Graves' disease was 10.9%. The serum IgE level in Graves' disease with, and without, allergic rhinitis were 903.1±1152.2U/mL and 560.8±1117.0U/mL, respectively, although there was no significancant difference between the two groups. According to the clinical stage, the serum TBII level was higher in the untreated Graves', and relapsed patients 49.9±23.9% and 21.1±3.1%, respectively, than in the treated group, 7.4±18.6% (p<0.05). The serum IgE level was higher in the untreated Graves' and relapsed patients 758.6±1250.2U/mL and 1198.5±1952.1U/mL, respectively, than in the treated group 233.8±432.7U/mL, although this was not significant. According to the duration of treatment, the serum TBII levels were higher in the untreated Graves' patients, and those treated for less than 1 year, than in those treated for more than 1 year, with values of 49.9±23.9, 24.8±3.8 and 2.22±1.97%, respectively (p<.05). The serum IgE level was higher in the untreated Graves' disease (758.6±1250.2U/mL) than in the groups treated for less than 12 months (158.3±91.5U/mL) and more than 12 months (252.7±483.4U/mL), but the differences were not significant. Conclusions: The concentration of IgE was high in Graves' patients, and although not statistically significant, the serum igE level in Graves' patients with allergic rhinitis was higher than those without. With regard to the clinical stage of Grave's disease, the change in the IgE level tended to follow that of the TBII. Further study will be required to define the possible role of IgE in the pathogenesis in Graves' disease (J Kor Soc Endocrinol 17:640∼648, 2002).

白질藜가 局所腦血流量 및 腦軟膜動脈에 미치는 影響

康成溶,韓宗鉉,金敬堯,白承和 한국전통의학연구소 1998 한국전통의학지 Vol.8 No.1

腦血管障碍에 대한 韓醫學的인 治療方法과 藥物開發을 目的으로 白질藜의 局所腦血流量 및 腦軟膜動脈 直徑 變化에 對한 實驗을 試圖하였다. 그 結果 1. 正常血壓白鼠에서의 血壓은 白질藜 投與로 變化를 나타내지 못했다. 2. 正常血壓白鼠에서의 局所腦血流量은 白질藜에 用量依存的으로 增加하였다. 3. Glibenclamide,methylene blue 와 indomethacin 前處置로 局所腦血流量의 增加를 有意하게 遮斷하였다. 4. 正常血壓白鼠에서의 腦軟膜動脈의 直徑은 濃度依存的으로 增을加하였다. 5. Glibenclamide 投與로 腦軟膜動脈의 增加를 有意하게 遮斷하였다. 以上의 結果에서 白질藜는 血壓에는 變化없이 局所腦血流量의 增加를 나타냈으며 局所腦血流量의 機轉은 prostaglandins와 cyclic GMP의 生成과 이온통로중에서 K^(+) 통로에,腦軟膜動脈의 直徑 變化는 ATP-의존성 K^(+) 통로에 關與하는 것을 알 수 있었다. Fructus Tribuli has been used in Korea for many centuries as a therapeutic agent for cerebral disease. The effect of Fructus Tribuli on the vascular system is not known. The purpose of this study was to determine the effect of Fructus Tribuli on regional cerebral blood flow and pial arterial diameter of rats. 1. Blood pressure was not affected by Fructus Tribuli in rats. 2. rCBF was increased by Fructus Tribuli in a dose-dependent manner. 3. Pretreatment with glibendamide, methylene blue or indomethacin significantly inhibited Fructus Tribuli induced increase in rCBF. 4. Pial arterial diameter was increased by Fructus Tribuli in a dose-dependent manner. 5. Pretreatment with glibendamide significantly inhibited the increased in pial arterial diameter induced by Fructus Tribuli. These results suggest that Fructus Tribuli causes a diverse response of regional cerebral blood flow(rCBF) and pial arterial diameter. The increase in rCBF is mediated by prostaglandins, cydic GMP and K^(+) channel and the increase in pial arteral diameter is mediated by ATP?dependent K^(+) channel.

연마 다듬질 가공면의 표면 미세형상 평가에 관한 연구

조남규,김현국,권기환,한창수,안유민,이성환,박균명 한국공작기계학회 2000 한국공작기계학회 추계학술대회논문집 Vol.2000 No.-

This paper describes the statistical analysis techniques for the surface roughness assessment of polished surfaces. In experiments, the polishing process of the sample surfaces which are manufactured by ball end mill is consist of two steps; the cusp removal process and the surface finishing process. For the cusp removal process, the criterion of cusp removal was established from the power spectrum analysis to assess the change of the cusp removal rate. For the finishing process, the surface was polished by the rotational CBN tool and vibration wood tool. And the surface quality of polished surface was assessed using the functional parameters based on the statistical values of surface profiles. Consequently, the surface finish performance of the polished surface using the vibration wood tool was improved.

손상정도계수와 외상치를 이용한 외상환자의 분석

송근정,장문준,김성중,조광현,김인병,최성욱,이한식 대한응급의학회 1993 대한응급의학회지 Vol.4 No.2

Trauma is one of the most common causes of death. Recently, injury severity score(ISS) is widely used to evaluate and classify the patients with multiple injury. Trauma score(TS) was developed as a means of providing rapid accurate assessment of the injured patient. Authors conducted a review of trauma patients who visited the emergency department of YongDong Severance Hospital from September 1992 to August 1993. ISS and TS were collected from comprehensive initial evaluation. The results were as follows : 1) The subjects were 10.2%(2,666 patients) of total 26,202 emergency patients. 2) Male to female ratio was 2.1 : 1. The age distribution was highest under 10 year(24.9%). The mean ISS was 3.5, and the mean ISS increased with ago. 3. Analysis of injury mechanism showed high incidence of traffic accident(35.3%), blunt trauma 25.7%, fall 24.2%, stabbing 10.7%, and others 4.3% in order. 4. The 8.0% of patients were admitted after initial management and their mean Iss was 12.6 mean TS was 15.5. 5. Among admitted traffic accident patients, the mean ISS of passenger T.A., pedestrian T.A. and driver T.A. were 19.0 ±9.9, 14.4 ±10.6, and 11.3 ±7.7 respectively. 6. Among 42 mortality cases, 25 patients were D.O.A. and 17 were expired. The mean ISS of D.O.A. Patients was 30.0; the mean Iss and mean Iss and mean TS of expired patients were 28.3 and 11.8 respectively. 7. The most common cause of death was head trauma(66.7%). 8. By comparing the ISS and TS of admitted and expired patients, mortality occurred above 16 point of ISS. The mortality increased with increasing ISS, but it was influenced by the trauma site and the severity of the particular injury site. Mortality also occurred below 15 point of TS, the mortality increased inversely with TS, and the mortality with TS, and the mortality was high below 13 point (above 40%).

심초음파로 결정된 응급 심낭천자술의 천자부위

김성환,황성오,이강현,조준휘,강구현,문중범,이승환,윤정한,최경훈,김영식 대한응급의학회 2000 대한응급의학회지 Vol.11 No.3

Background: The aim of this study was to determine whether the conventional subcostal approach is suitable for emergency pericardiocentesis in patients with cardiac tamponade or impending cardiac tamponade. Methods: This study was a prospective, observational study conducted at the emergency department of a tertiary hospital, Patients who had symptomatic pericardial effusion and who needed emergency pericardiocentesis in the emergency department were included in this study. We measured the epicardium-to-pericardium distance at the subcostal, parasternal, and apical area with two-dimensional echocardiography to determine the appropriate puncture site for pericardiocentesis. An epicardium-to-pericardium distance of more than 1.0 cm was considered as the primary safety factor in determining the Puncture site for pericardiocentesis. The skin-to-pericardium distance was considered as secondary safety factor. Results: Ninety-five consecutive patients(55 males and 40 females; total mean age: 53 year old) with cardiac tamponade or impending cardiac tamponade were enrolled in this study. The puncture site for pericardiocentesis, as determined by echocardiography, was the subcostal area in 43 patients(45%), the apical area in 40 patients(42%), the left parasternal area In 11 patients(12%), and the right parastemal area in one patient(1%). Pericardiocentesis failed in 2 patients(2%) with the subcostal approach and in one patient(1%) with the apical approach. The average epicardium-to-pericardium distance was 31 ±21 mm in patients with the subcostal approach and 21±8 mm in patients with other approaches. There were no differences in the amount of pericardial fluid and in the intraperical pressure among patient groups according to puncture site. There were two procedure related complications: a puncture of the right ventricle with the subcostal approach and a ventricular tachycardia with the apical approach.

이중혈류유발 심폐소생술이 심정지를 유발한 개의 단기 생존율에 미치는 영향

황성오,조준휘,강구현,김성환,문중범,이강현,이승환,윤정한,최경훈,홍은석 대한응급의학회 2000 대한응급의학회지 Vol.11 No.3

Background and Objectives: We previously reported that, compared with standard cardiopulmonary resuscitation(S-CPR), better hemodynamic effects could be achieved by simultaneous sterno-thoracic cardiopulmonary resuscitation(SST-CPR) in which we compressed the sternum and constricted the thorax circumferentially during the systolic period by using a device. This study was designed to assess whether SST-CPR, compared with S-CPR, improve the survival rate of dogs with cardiac arrest. Subjects and methods: Twenty-five mongrel dogs(19∼31㎏) were enrolled in this study. After four minutes of ventricular fibrillation induced by an AC current, animals were randomized to resuscitate with either S-CPR(n=13) or SST-CPR(n=12). Epinephrine(1 ㎎) was injected into the right atrium every three minutes after the beginning of CPR. Defibrillation was attempted after 6 minutes of CPR. Standard advanced cardiac life support was started if defibrillation was not successful. Results: SST-CPR resulted in significantly(p<0.001) higher systolic arterial pressure(91±47 vs 47±24 ㎜ Hg), diastolic pressure(43±24 vs 17±10 ㎜ Hg), coronary perfusion pressure(35±25 vs 13±9㎜ Hg), and end tidal CO2 tension(9±4 vs 3±2 ㎜ Hg). Two of 13 animals(15 %) resuscitated with S-CPR and six of 12 animals(50%) resuscitated with SST-CPR survived until 12 hours after cardiac arrest(p<0.05). Donclusion: SST-CPR, compared with S-CPR, improves the short-term survival rate in canine cardiac arrest.

Panipenem을 포함한 Carbapenem 계열 항생제의 몇 가지 임상균주에 대한 시험관내 항균력

이동건,김명신,강진한,전혜선,최수미,위성헌,김상일,최정현,유진홍,신완식,강문원 대한감염학회 2003 감염과 화학요법 Vol.35 No.2

목적 : Panipenem은 일본에서 개발된 카바페넴계 항생제로 그람양성균, 그람음성균, 혐기균에 이르기까지 광범위한 항균력을 나타낸다고 보고되고 있지만 국내에서 분리되는 균주에 대한 감수성 검사결과는 아직 없다. 본 연구에서는 임상에서 분리된 E. coli, K. pneumoniae, P. aeruginosa, S. pneumoniae 균주를 대상으로 carbapenem 계열 및 몇 가지 항생제와 감수성을 비교하고, 특히 P. aeruginosa의 경우 carbapenem의 효과를 Muller-Hinton agar (MHA)가 반감시킬 수 있는 특성을 고려하여 감수성에 변화가 있는지 확인하고자 하였다. 방법 : 2002년 3월부터 6월까지 가톨릭대학교 성모병원, 강남성모병원, 성가병원, 성모자애병원, 성빈센트병원에서 분리된 임상균주 E. coli, K. pneumoniae, P. aeruginosa, S. pneumoniae를 대상으로 하였다. 항생제 감수성 검사는 NCCLS 기준에 따랐고 P. aeruginosa의 경우 MHA 이외에 minimal agar Davis (MAD)를 추가로 사용하였다. 감수성 결과 해석시 panipenem은 imipenem과 같은 기준을 적용하였다. 결과 : E. coli, K. pneumoniae, P. aeruginosa는 각각 100균주였고, S. penumoniae는 134균주였다(PSSP 41, PNSP 93균주). E. coli, K. pneumoniae는 모든 균주가 imipenem, meropenem, panipenem에 대해 감수성을 보였다. P. aeruginosa의 경우 imipenem, meropenem, panipenem, ceftazidime의 MIC_(90)은 각각 16, 8, 32, 64㎍/mL이었다. MHA와 MAD 배지를 이용하여 P. aeruginosa에 대한 항생제 감수성을 비교해 본 결과 imipenem, panipenem의 MIC_(90)가 각각 16, 32㎍/mL에서 8㎍/mL로 감소하였고, imipenem에 비해 panipenem이 더 많이 감소하였다. S. pneumoniae의 경우 PSSP는 imipenem, meropenem, panipenem에 대해 모두 내성이 없었고 PNSP는 imipenem, meropenem, panipenem에 대한 MIC_(90)가 각각 1, 2, 0.25㎍/mL이었다. 결론 : 결론적으로 panipenem은 E. coli, K. pneumoniae에 대해 기존의 카바페넴계 항생제와 유사한 우수한 항균력을 보였다. P. aeruginosa의 경우 ceftazidime, imipenem과 비슷한 항균력을 보였고 아미노산 함량이 적은 배지를 사용함에 따라 MIC가 낮아졌으며 imipenem보다 더 많은 영향을 받았다. S. pneumoniae의 경우 특히 PNSP에서 기존의 카바페넴계 항생제보다 우수한 항균력을 보였다. Panipenem은 주요 그람음성균 및 폐렴연쇄구균 감염에 유용할 것으로 기대된다. Background : Panipenern (PAPM) is a new carbapenern which has an enhanced broad spectrum against both gram-positive and negative organisms. The aim of study was to compare the activities of PAPM with those of imipenern (IMPM), meropenern (MRPM) against several clinical isolates in Korea. Methods : We tested the in vitro antimicrobial activities of PAPM, IMPM, and MRPM against total 300 clinical isolates of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa and 134 Streptococcus pneumoniae collected from 5 different university hospitals. Using NCCLS guidelines, MICs of PAPM, IMPM, MRPM, and/or ceftazidime were determined. Results : All isolates of E. coli and K. pneumoniae were susceptible to PAPM, IMPM and MRPM. MIG_(90) of PAPM, IMPM, and MRPM against P. aeruginosa were 32, 16, and 8 ㎍/mL, respectively. Comparing Mueller-Hinton agar (MHA) and minimal agar Davis (MAD), the MIG_(go) of PAPM and IMPM were reduced from 16 and 32 ㎍/mL to 8 and 8 ㎍/mL, respectively. PAPM was more influenced by MAD than IMPM. All isolates of penicillin susceptible S. pneumoniae showed 0% of resistance to the carbapenems tested. MIC_(90) of PAPM, IMPM and PRPM against penicillin non-susceptible S. pneumoniae were 0.25, 1 and 2 ㎍/mL, respectively. Conclusion : Panipenern could be one of the potentially useful drugs for the treatment of infections caused by E. coli, K. pneumoniae, and S. pneumoniae. We also showed that PAPM had good anti-pseudomonal activity when examined in MAD, the amino acid-limited media. Therefore, it could be useful for the treatment of infections caused by P. aeruginosa.

LNG FSRU의 재기화 공정에서 폐에너지회수시스템의 엑서지 분석

한승현 ( Seoung Hyun Han ),조재호 ( Jae Ho Jo ),권정태 ( Jeong-tae Kwon ),박경우 ( Kyoungwoo Park ),최병철 ( Byung Chul Choi ) 한국신·재생에너지학회 2022 신재생에너지 Vol.18 No.2

In this study, the exergy characteristics were analyzed, according to the mass flow rate of the propane working fluid and the pressure change in the turbine inlet, for the efficient recovery of cold energy and exhaust heat by the waste energy recovery system applied to the LNG FSRU regasification process. When the turbine inlet pressure and mass flow rate of the Primary Rankine Cycle were kept constant, the exergy efficiency and the net power increased. This occurred as the turbine inlet pressure and the mass flow rate of the working fluid increased in the Secondary Rankine Cycle, respectively, and the maximum values were confirmed. In this regard, the fluctuations in the exergy rate flowing into and out of the system and the exergy rate destroyed by pumps, evaporators, turbines, and LNG heat exchangers (condensers) were examined in detail.

1분과 : 토양 코어 및 미니라이조트론을 이용한 소나무 임분의 세근 바이오매스 연구

한승현 ( Seung Hyun Han ),윤태경 ( Tae Kyung Yoon ),한새롬 ( Sae Rom Han ),윤순진 ( Soon Jin Yun ),이선정 ( Sun Jeoung Lee ),김성준 ( Seoung Jun Kim ),장한나 ( Han Na Chang ),손요환 ( Yo Whan Son ) 한국임학회 2014 한국산림과학회지 Vol.103 No.1

본 연구는 소나무 임분을 대상으로 토양 코어 샘플링과 미니라이조트론 방법을 이용하여 세근의 분포를 파악하고, 미니라이조트론 자료를 세근 바이오매스로 환산할 수 있는 변환계수와 회귀식을 개발하는 목적으로 수행되었다. 토양 코어 샘플링은 2012년 10월부터 2013년 9월까지 겨울을 제외하고 매월 1회씩 총 9회 실시하여 세근 바이오매스를 측정하였고, 미니라이조트론을 이용하여 2013년 5월부터 8월까지 매월 1회씩 총 4회 세근 표면적을 측정하였다. 0-30 cm 토양 깊이에서 세근 바이오매스와 표면적은 지표에 가까울수록 유의하게 높았으며, 계절별 바이오매스(kg ha-1)는 여름(3,762.4)과 봄(3,398.0)에 가을(2,551.6)보다 유의하게 높은 값을 보였다. 이와 같은 토양 깊이별 분포는 토양의 양분, 용적밀도 그리고 온도 등의 차이 때문으로 사료되며, 계절적 경향은 대기 온도 및 토양 온도 변화에 의해 나타나는 것으로 보인다. 또한 토양 깊이별 세근 표면적과 바이오매스 사이의 변환계수를 구하고, 이를 통하여 미니라이조트론 자료를 환산한 세근 바이오매스와 토양 코어 샘플링 자료인 실측값 사이의 선형회귀식(y = 79.7 + 0.93x, R2= 0.81)을 개발하였다. 본 연구에서 개발된 변환계수 및 회귀식은 추후 국내 소나무림의 장기적인세근 동태를 추정하는데 활용될 수 있을 것으로 기대된다. Fine root distribution was investigated in Pinus densiflora stands using soil core sampling andminirhizotrons, and conversion factors and regression equations were developed for converting minirhizotrondata into fine root biomass. Fine root biomass was measured by soil core sampling from October, 2012 to September, 2013 once a month except for the winter, and surface area of fine roots was estimated byminirhizotrons from May to August, 2013 once a month. Fine root biomass and surface area were significantly higher in the upper soil layers than in the lower soil layers. Fine root biomass showed seasonal patterns; the mean fine root biomass (kg ha-1) in summer (3,762.4) and spring (3,398.0) was significantly higher than that in autumn (2,551.6). Vertical and seasonal patterns of fine root biomass might be related to the soil bulk density, nutrient content and temperature with soil depth, and seasonal changes of soil and air temperature. Conversion factors (CF) between fine root surface area from minirhizotron data and fine root biomass from soil core sampling were developed for the three soil depths. Then a linear regression equation was developed between the predicted fine root biomass using CF and the measured fine root biomass (y = 79.7 + 0.93x, R2= 0.81). We expect to estimate the long-term dynamics of fine roots using CF and regression equation for P. densifloraforests in Korea.

Automated Non-Volatile Radionuclide Separation System for Prompt Analysis of LILWs

Han-byeol Kim,Dae-hee Kim,Hyun-soo Kim,Sun-min Park,Jong-kwang Lee,Hong Joo Ahn,Taeyong Noh,Seoung-kyo Yoo 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.1

According to Article 4 and 5 of the Nuclear Safety and Security Commission (NSSC) Notice No. 2020-6, radioactive waste packages should be classified by radioactive levels, and finally permanently shipped to underground or surface disposal facilities. The level of the radioactive waste package is determined based on the concentrations of the radionuclides suggested in Article 8 of NSSC Notice No. 2021-26. Since most of the radionuclides in radioactive wastes are beta nuclides, chemical separation and quantification of the target nuclides are essential. Conventional methods to classify chemically non-volatile radionuclides such as Tc-99, Sr-90, Nb- 94, Fe-55 take a lot of time (about 5 days) and have low efficiency. An automated non-volatile nuclide analysis system based on the continuous chemical separation method of radionuclides has been developed to compensate for this disadvantages of the conventional method in this study. The features of the automated non-volatile nuclide separation system are as follows. First, the amount of secondary waste generated during the chemical separation process is very small. That is, by adopting an open-bed resin column method instead of a closed-bed resin column method, additional fittings and connector are unnecessary during the chemical separation. In addition, because the peristaltic pump is supplied for the sample and solution respectively, it is great effective to prevent cross-contamination between radioactive samples and the acid stock solution for analysis. Second, the factors that may affect results, such as solution amount, operating time and flow rate, are almost constant. By mechanically controlling the flow rate precisely, the operating time and additional factors required during the separation process can be adjusted and predicted in advance, and the uncertainty of the chemical separation process can be significantly reduced. Finally, it is highly usable not only in the continuous separation process but also in the individual separation process. It can be applied to the individual separation process because the user can set the individual sequence using the program. As a result of the performance evaluation of the automation system, recovery rates of about 80–90% and reproducibility within 5% were secured for all of the radionuclides. Furthermore, it was confirmed that the actual work time was reduced by more than 50% compared to the previous manual method. (It was confirmed that the operation time required during the separation process was reduced from 6 days to 3 days.) Based on these results, the automation system is expected to improve the safety of workers in radiation exposure, reduce human error, and improve data reliability.