농약의 물리화학적 특성 연구 (II) Flupyrazofos의 수용성, 가수분해, 증기압, 옥탄올/물 분배계수

김정한,김용화,김균,Kim, Jeong-Han,Kim, Yong-Hwa,Kim, Kyun 한국응용생명화학회 1997 Applied Biological Chemistry (Appl Biol Chem) Vol.43 No.1

국내에서 최초로 합성, 개발된 유기인계 살충제인 flupyrazofos(KH-502)의 물리화학적 특성으로 수용성, 가수분해, 증기압, 분배계수를 EPA와 OECD 방법에 준하여 측정하였다. 수용성은 $25^{\circ}C$에서 0.80 ppm으로 낮았고 가수분해 반감기는 $25^{\circ}C$에서 266.5시간(pH 4.0), 180.0시간(pH 7.0), 120.9시간(pH 9.0)으로 알칼리 조건에서 불안정하였으며 $40^{\circ}C$에서는 $25^{\circ}C$보다 $2{\sim}4$배 정도 가수분해가 빠르게 진행되었다. 상은($25^{\circ}C$)에서의 증기압은 $2.81{\times}10^{-5}$ torr로 측정되었고, 다른 두 온도(35, $45^{\circ}C$)에서 증기압을 측정하여 log P=0.673-(1565.4/T)라는 관계식을 구하였다. Flupyrazofos의 상온($25^{\circ}C$)에서의 증기압은 diazinon과 유사한 수준이었고, DDVP보다는 약 1,000배 정도 낮은 수치로 휘발에 의하여 환경에 영향을 미칠 가능성은 낮을 것으로 판단되었다. Flupyrazofos의 옥탄올/물 분배계수치를 보면(log Kow=5.24) 먹이연쇄를 통한 생물농축이 예상되나 비교적 가수분해가 빠르기 때문에 비록 수계에 노출된다고 하여도 그 가능성은 매우 낮을 것으로 사료된다. Several physicochemical properties such as water solubility, vapor pressure, hydrolysis and octanol/water partition coefficient(Kow) of flupyrazofos, the first organophosphorus insecticide developed in Korea, were measured based on EPA and OECD methods. Water solubility was low showing 0.80 ppm at $25^{\circ}C$ and in hydrolysis study, half-life at $25^{\circ}C$ was 266.5 hr(pH 4.0), 180.0 hr(pH 7.0) and 120.9 hr(pH 9.0) demonstrating instability in alkaline solution. At $40^{\circ}C$ hydrolysis rate was $2{\sim}4$ times higher than that at $25^{\circ}C$. The equation log P=0.673-(1565.4/T) was obtained from vapor pressure experiments at three different temperatures (25, 35, $45^{\circ}C$) and $2.81{\times}10^{-5}$ torr was obtained at $25^{\circ}C$. This value is similar to that of diazinon and 1,000 times lower than that of DDVP suggesting it would not give environmental contamination by volatilization. High log Kow(5.24) was observed and this might result in bioconcentration through food chain. However, its possibility is not likely to be high due to its relatively rapid hydrolysis.

갑상선 수질암 환자에서 칼시토닌 정상화와 관련된 예후인자

김정한,김상욱,남석진,서정민,양정현,Jeong-Han Kim,M.D.,Sang-wook Kim,M.D.,Seok-Jin Nam,M.D.,Jeong-meen Seo,M.D. and Jung-Hyun Yang,M.D. 대한갑상선-내분비외과학회 2003 The Koreran journal of Endocrine Surgery Vol.3 No.2

Purpose: Medullary thyroid carcinoma (MTC) is an uncommon thyroid tumor. Calcitonin (CT) is a very specific marker of this cancer and has a major place in the postoperative follow-up. The aim of this study was to evaluate the outcome of surgical treatment for MTC and to identify the prognostic factors for the normalization of CT after surgery. Methods: Retrospective analysis of 29 patients with MTC from 1994 to 2002 in Samsung Medical Center was carried out. Results: 22 female and 7 male were identified and their mean age was 46.9 years. Mean follow-up was 42.7 months. 5 patients had MEN2a; all had pheochromocytoma and 2 among them had hyperplasia of parathyroid gland. The majority of patients (86.2%) presented with a palpable neck mass and 23 patients were diagnosed with MTC preoperatively. Total thyroidectomy with or without neck dissection was performed in all patients. Cervical lymph node involvement was detected in 34.5% of these patients. Basal CT levels were found to be normal in 15 patients (51.7%) postoperatively. 1 distant metastasis, 6 loco-regional metastases and 1 death were observed during follow-up period. Overall survival rate was 94.7% and disease-free survival rate was 62.9% at 5 years. Univariate analysis showed that extra-thyroidal invasion and involvement of lymph node were significant prognostic factors for normalization of CT after surgery. Conclusion: Considering the high recurrence rate in the thyroid bed and cervical lymph node, more extensive and thorough neck dissection is needed for the treatment of MTC. (Korean J Endocrine Surg 2003;3:121-126)

족근골 유합의 발생 빈도: 단일 기관 자기공명영상 분석

김정한,곽희철,이창락,김영준,김전교,이선주,이정한,박준호,Kim, Jung-Han,Gwak, Heui-Chul,Lee, Chang-Rak,Kim, Young-Jun,Kim, Jeon-Gyo,Lee, Sun-Joo,Lee, Jeong-Han,Park, Jun-Ho 대한족부족관절학회 2016 대한족부족관절학회지 Vol.20 No.3

Purpose: Tarsal coalition results from defects during the developmental stage and produes ankle pain and limitations in the range of motions. Its incidence has been reported to be 1%, but there has not been any reports with respect to Koreans. Therefore, we evaluated the prevalence of tarsal coalition in Koreans. Materials and Methods: Between 2005 and 2014, we analyzed a total of 733 cases of foot and ankle magnetic resonance imaging (MRI) in our hospital. There were 391 men and 342 women. All MRI readings were read by a radiologist in our hospital. We classified the coalitions in accordance with the histological and anatomical characteristics, and calculated the prevalence in each group. Moreover, we tried to determine the prevalence of tarsal coalitions in accordance with sex, age, and proportion of the symptomatic tarsal coalitions. Results: There were a total of 11 MRIs of tarsal coalition - 9 talocalcaneal coalitions, 1 calcaneocuboidal coalition, and 1 calcaneonavicular coalition. Nine tarsal coalitions were observed in men and 2 in women. Conclusion: Through this study, we found that the prevalence of tarsal coalition, including the asymptomatic patients, is similar to the previously known prevalence (1%). By getting more MRIs of the foot and ankle, we could better represent the prevalence of tarsal coalitions in Koreans.

농약은 어떤 모양일까?

김정한,Kim, Jeong-Han 한국작물보호협회 2005 자연과 농업 Vol.26 No.8

농약잔류허용기준? 안전사용기준?

김정한,Kim, Jeong-Han 한국작물보호협회 2005 자연과 농업 Vol.26 No.10

“시중 채소류 잔류농약 범벅”신문이나 TV에 자주 등장하는 낯익은(?) 제목이다. 그리고는“조사대상 농산물 중 OO% 허용기준치초과. 최고 OO배에 달해, 사용이 금지된 농약도 나와, 잔류농약은 식품과 함께 일생동안 섭취되기 때문에 만성중독 가능성을 배제할 수 없다”같은 내용이 그 뒤를 잇는다. “일생동안 섭취”문제는 이미 지난 10월호에서“1일 섭취허용량” 을 다루었기 때문에 이해가 된다. 하지만 식생활을 하면서 농약 섭취가 1일섭취허용량 이하로 되도록 하려면 식품에 농약이 어느 정도까지 있어야 안전한가?”가 의문이다. 그 허용기준이 농산물(식품) 중“농약잔류허용기준”이다. 이는 보통“기준치, 허용치, 허용기준, 허용기준치, 잔류허용기준”등으로 불리우고 있다.

1-페닐술포닐 부탄-2-온의 빵효모 환원 : 손쉬운 (S)-(+)-3-옥탄올의 합성

김정한,오원택,임정훈,Jung-Han Kim,Won-Taek Oh,Jeong-Hoon Lim 대한화학회 1991 대한화학회지 Vol.35 No.5

일반화 공간변조를 위한 저복잡도 강인 최대 우도 신호 검파

김정한,윤태선,오세훈,이경천,Kim, Jeong-Han,Yoon, Tae-Seon,Oh, Se-Hoon,Lee, Kyungchun 한국정보통신학회 2017 한국정보통신학회논문지 Vol.21 No.3

본 논문에서는 다중 안테나 구조 중 일부 송신 안테나만 활성화하고 활성 안테나의 인덱스를 통해 정보를 전송하는 일반화 공간변조(Generalized Spatial Modulation)시스템을 위한 최대우도 신호 검파 방법을 제안한다. 제안 최대 우도 수신기는 기존의 채널 정보 오차에 강인한 최대 우도 수신기와 비교하여 공분산 행렬을 추정할 때 후보 해 집합을 확률적으로 추출하여 공분산 행렬을 추정함으로써 시스템 복잡도를 크게 줄이도록 한다. 모의 실험을 통해 제안 최대 우도 수신기가 기존의 채널 정보 오차를 고려하지 않는 수신기보다 높은 수신 성능을 가지며, 기존 강인 최대우도 수신기와 비교하여 동일한 비트 오류율 성능을 가지면서도 큰 폭으로 계산 복잡도를 낮춤을 확인하였다. In this paper, we propose a maximum likelihood signal detection scheme for a generalized spatial modulation system that activates only a subset of transmit antennas among multiple antennas and transmits information through the indexes of active antennas as well as through the transmit symbols. The proposed maximum likelihood receiver extracts a set of candidate solutions based on their a posteriori probabilities to lower the computational load of the robust receiver under channel information errors. Then, the chosen candidate solutions are exploited to estimate the covariance matrix of effective noise. Simulation results show that the proposed maximum likelihood detection scheme achieves better error performance than a receiver that does not take into account the channel information errors. It is also seen that it reduces the computational complexity with the same bit error rate performance as the conventional robust maximum likelihood receiver.

당뇨병의 진단과 경구 당부하검사

김정한,Kim, Jeong-Han 사단법인 한국당뇨협회 2005 당뇨 Vol.186 No.-

회원작품: 창원시립 문신 원형 전시관

김정한,Kim, Jeong-Han 대한건축사협회 2011 建築士 Vol.2011 No.5

유기인계 화합물의 산화대사중 반응성 중간체와 반응기작에 관한 고찰

김정한,박창규 ( Jeong Han Kim,Robert F . Toia,Chang Kyu Park ) 한국환경농학회 1996 한국환경농학회지 Vol.15 No.2

Organophosphorus pesticides, which are an important part of synthetic pesticides in current use contain sulfur atom in their molecules and can be activated or detoxified by environmental and/or biological metabolism. Among the related metabolic reactions, oxidative processes are particularly important with their final products and the study on the reactive intermediates formed in those reactions is essential to elucidate the metabolic pathways and mechanisms and to understand the toxicological properties. This review dealt with the reactive intermediates formed in various reactions from the structural and mechanistic point of view for organophosphorus pesticides and related compounds.