Effect of AlF₃ on Zr Electrorefining Process in Chloride-Fluoride Mixed Salts for the Treatment of Cladding Hull Wastes

이창화,강덕윤,이성재,이종현,Lee, Chang Hwa,Kang, Deok Yoon,Lee, Sung-Jai,Lee, Jong-Hyeon Korean Radioactive Waste Society 2019 방사성폐기물학회지 Vol.17 No.2

삼불화알루미늄($AlF_3$)이 포함된 염화물-불화물 혼합 용융염에서 ZIRLO 튜브를 이용한 지르코늄 전해정련공정을 실증하였다. 순환 전압전류실험 결과, $AlF_3$의 농도가 증가함에 따라 금속환원의 개시 전위가 일정하게 증가하고 지르코늄-알루미늄 합금형성과 관련된 추가적인 peak의 크기가 점차 증가하는 것으로 나타났다. 전류조절 전착법과 달리, -1.2 V의 일정전위에서 수행한 지르코늄 전해정련에서 방사형 판 구조의 지르코늄 성장이 염의 상단 표면에서 확연하게 나타났으며, 전착물 지름의 크기는 $AlF_3$의 농도에 따라 점차 증가하는 것으로 나타났다. 주사전자현미경(SEM)과 에너지 분산 X선 분광기(EDX)와 X선 광전자 분광기(XPS)를 이용하여 판 구조의 지르코늄 전착물을 분석한 결과, 극미량의 알루미늄이 지르코늄-알루미늄 합금 형태로 존재하며, 전착물의 상단과 하단 간에 서로 다른 화학성분구조를 갖는 것으로 나타났다. $AlF_3$의 첨가는 전착물 내 잔류염 양을 줄이고, 지르코늄 회수를 위한 전류효율을 향상시키는 데 효과적인 것으로 나타났다.

호산구성 봉소염

이창화,김상용,손형선 ( Chang Hwa Lee,Sang Yong Kim,Hyung Sun Sohn ) 대한피부과학회 1988 대한피부과학회지 Vol.26 No.2

We report a 44-year-old female patient with Eosinophilic cellulitis who had developed pruritic erythematous plaque on the right lower abdomen since two months ago. The blood eosinophil count was 2,066/mm at first visit. This lesion responded well to cortieosteroid therapy. However new erythematous swelling reappeared on the left lower abdomen and left inner thigh 3 months after the first treatment. A biopsy specimen taken from an erythematous plaque showed many flame figures and diffuse infiltration of eosinophils and histiocytes in the lower dermis and subcutaneous fat tissue.

소련의 단거리유도탄-원거리작전능력을 갖는 재래식 무기

이창화,Lee, Chang-Hwa 한국방위산업진흥회 1986 國防과 技術 Vol.- No.86

서버 시스템 내의 오류 정정 코드 분석에 관한 연구

이창화,Lee, Chang-Hwa 한국군사과학기술학회 2005 한국군사과학기술학회지 Vol.8 No.3

In this paper, a novel method is proposed how the ECC(Error Correction Code) in server system can be investigated and the robustness of each system against noisy environment and element failure in memory module has been verified. Chipset manufacturers have hided the algorithm of their Hamming code and the user has difficulty in verification of the robustness of each system. The proposed method is very simple, but the outputs of the experiment explain the core ability of error correction in server system and helps the detection of the failure element. On the basis of these results, we could expect the robustness of digitalized weapon system and the efficient design of our own error correction code.

신장 ; 혈액투석에서 투석액 칼슘농도와 칼시트리올이 골대사에 미치는 영향

염지연 ( Ji Youn Youm ),김현철 ( Hyun Chul Kim ),이영철 ( Young Chul Lee ),최종욱 ( Jong Wook Choi ),박준성 ( Joon Sung Park ),이창화 ( Chang Hwa Lee ),강종명 ( Chong Myung Kang ),김근호 ( Gheun Ho Kim ) 대한내과학회 2011 대한내과학회지 Vol.81 No.6

목적: 현재 혈액투석에 사용 중인 투석액 칼슘 농도는 1.25mmol/L, 1.5 mmol/L, 1.75 mmol/L로 구분된다. 고칼슘 투석액은 부갑상선호르몬의 분비를 억제시키는 효과가 있으나 고칼슘혈증 위험을 증가시키고, 저칼슘 투석액은 adynamic bone disease을 개선시키는 효과가 있으나 칼슘 평형을 악화시킬 우려가 있으므로 투석액 칼슘 농도의 적절한 선택은 쉽지 않다. 저자들은 표준칼슘 농도인 1.5 mmol/L 투석액을 사용하였을 때 칼시트리올 용량 변화와 아울러 요독성 골질환에 미치는 효과를 평가하고자 하였다. 방법: 투석액 칼슘 농도 1.75 mmol/L로 1년 이상 혈액투석 중인 환자 36명에서 투석액 칼슘 농도를 1.5 mmol/L로 전환 후 1년간 경과를 추적하였다. 투석액 칼슘 농도를 낮추기3개월 전에 측정한 혈청 iPTH 농도에 따라 환자를 1군(iPTH< 150 pg/mL, n=21), 2군(iPTH 150-300 pg/mL, n=7), 3군(iPTH>300 pg/mL, n=8)으로 구분하여 혈청 칼슘, 인, 알칼리포스파타제, iPTH 농도를 3개월 간격으로 측정하였고, 인결합제 및 칼시트리올 용량 변화를 조사하였다. 결과: 투석액 칼슘 농도 1.75 mmol/L 사용 중 1군, 2군 및 3군의 iPTH 농도는 각각 57±48 pg/mL, 191±46 pg/mL, 589±200 pg/mL로 유의한 차이가 있었다(p<0.001). 투석액칼슘 농도를 1.5 mmol/L로 전환 후 1군에서 혈청 iPTH가 12개월에 걸쳐 유의하게 증가하였다(p=0.01). 3개월째부터 증가가 현저하여(57±48 vs. 287±266 pg/mL, p<0.01) 이후증가세를 유지하였다. 그러나 2군에서는 유의한 변화가 없었고, 3군의 혈청 iPTH는 12개월에 걸쳐 유의하게 감소하였는데(p=0.02) 특히 9개월째 감소가 기저치에 비해 낮았다(589±200 vs. 242±246 pg/mL, p<0.01). 혈청 알칼리포스파타제도 혈청 iPTH와 유사한 변화 양상을 보였다. 투석액칼슘 농도를 1.5 mmol/L로 전환한 후 1군과 2군에서 인결합제와 칼시트리올 투여 용량의 유의한 변화는 없었으나, 3군에서 칼시트리올 용량이 6개월째부터 유의하게 증가하였고 (4.4±5.1 vs. 9.6±2.9 μg/month, p<0.05) 나머지 기간 동안증가 추세를 유지하였다. 결론: 혈액투석액 칼슘 농도를 1.75 mmol/L에서 1.5 mmol/L으로 전환한 후 적절한 인결합제와 칼시트리올 투여 용량을 조정하면서 adynamic bone disease와 이차성 부갑상선항진증환자에서 혈청 iPTH 측정치가 호전되는 경향을 보였다. 신성골형성장애가 있는 혈액투석 환자에서 투석액 칼슘 농도 1.5 mmol/L를 선택하는 것이 효과적일 수 있다. Background/Aims: Whereas higher dialysate calcium (Ca) levels may pose a risk of hypercalcemia, lower levels may induce a negative Ca balance. We evaluated the effect of lowering dialysate Ca levels from 1.75 to 1.5 mmol/L and explored the appropriate use of calcitriol to regulate bone metabolism in hemodialysis patients. Methods: The dialysate Ca levels of 36 patients were reduced from 1.75 to 1.5 mmol/L. They were divided into three groups according to basal intact parathyroid hormone (iPTH) level (group 1, iPTH<150 pg/mL, n=21; group 2, iPTH 150-300 pg/mL, n=7; group 3, iPTH>300 pg/mL, n=8). Data were collected at 3-month intervals for 1 year. Results: Throughout the study period, no significant difference in phosphate binders, serum Ca, phosphorus (P), or Ca × P products was observed among groups. However, iPTH, alkaline phosphatase (AP), and calcitriol dosage patterns differed among groups. In group 1, iPTH and AP increased significantly over 12 months (p=0.01). In group 2, iPTH and AP showed no significant changes. In group 3, iPTH and AP declined significantly over 12 months (p=0.02). Calcitriol dosage did not change in groups 1 and 2, but increased significantly in group 3 (p=0.001). Conclusions: After converting hemodialysate Ca levels from 1.75 to 1.5 mmol/L, the initially different iPTH concentrations converged to a modestly elevated level. The use of 1.5 mmol/L hemodialysate Ca may thus be appropriate for both high- and low-turnover bone disease if phosphate binders and calcitriol are combined appropriately. (Korean J Med 2011;81:751-758)

혈액투석 유지 요법 환자에서 하대정맥 직경과 좌심실 비대와의 관계

신진호(Jin Ho Shin),박찬현(Chan Hyun Park),최정혜(Jung Hye Choi),이창화(Chang Hwa Lee),강경원(Kyoung Won Kahng),김상목(Sang Mok Kim),강종명(Chong Myung Kang),박한철(Han Chul Park),장성렬(Sung Ryul Chang),이방헌(Bang Hun Lee) 대한내과학회 1998 대한내과학회지 Vol.55 No.5

N/A Background: Volume overload is one of the most important, correctable factor far blood sure control in hemodialysis patient. But objective parameter for the ideal body weight is not available in clinical field yet. Recently inferior vena caval examination became a possible candidate for an objective parameter for intravascular volume status. Therefore we investigated how inferior vena cava changes during hemodialysis compared with total amount of ultrafiltration and ANP, and also the effect of changes of IVC diameter on LVK Methods: 43 patients on stable maintainance hemodialysis were enrolled. Among them, 21 patients were on antihypertensive medication. Just before and after the hemodialysis, inferior vena cava diameter, plasma atrial natriuretic peptide and left ventricular mass index were measured for each patient. Inferior vena cava was examined at the level just below the hepatic vein during quiet respiration and left ventricular mass index was calculated. Results- Inferior vena cava at expiration(IVCe) was significantly decreased during hemodialysis(before hemodialysis 21.9 4.9 mm, after hemodialysis 18.3 4.4 mm, p = 0.02). Collasibility index was significantly increased during hemodialysis (before hemodialysis 0.24 0.15, after hemodialysis 0.41 0.19, p< 0.001). Atrial natriuretic peptide(ANP) was significantly decreased during hemodialysis (before hemodialysis 252.3±119.0 pg/ml, after hemodialysis 185.6±93.2 pg/ml, p<0.001). Total ultrafiltration amount was significantly correlated with collapsibility change(r=-0.40) and change of ANP(r=-0.41). Left ventricular mass index was correlated with interdialysis weight gain(r=0.39, p<0.05), IVCe after hemodialysis(r=0.48, p<0.05) in univariate analysis but not in multivariate analysis. Conclusion: Collapsibility index of inferior vena cava, IVC diameter and ANP changes reflect the volume change during the hemodiaylsis. Therefore 1VC examination can be an objective parameter for volume change during hemodialysis. Postdialysis 1VCe correlates weakly with left ventricular mass index but it cannot be an independant risk factor for left ventricular hypertrophy in our study.

녹농균 괴저

이창화(Chang Hwa Lee),김상용(Sang Yong Kim),박석돈(Seok Don Park) 대한피부과학회 1988 대한피부과학회지 Vol.26 No.1

Forytfour-year-old female inpatient, who was gravely ill, developed vesicobullae on the greenish patches surrounded by narrow red to brown halo in the left lower extremity. Two years ago, she had treated by surgical operation and radiation therapy for cervix cancer. Blood and bullous fluid cultures showed Pseudomonas aeruginosa. She developed gangrenous and mummificated skin lesions after septic shock therapy but died due to disseminated intravascular coagulation.

전계방출을 위한 고종횡비 투명 팁 어레이 제작

이창화(Chang Hwa Lee),이석우(Seok Woo Lee),이승섭(Seung Seob Lee) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.5

정상 섬유아세포와 말초 혈액 단핵 세포가 편평상피 세포암 세포 ( SCL - 1 ) 에 미치는 영향

이창화(Chang Hwa Lee),김동림(Dong Lim Kim),박석돈(Seok Don Park) 대한피부과학회 1989 대한피부과학회지 Vol.27 No.3

Many carcinomas have an active mononuclear cell infiltrates surrounding tumor. Various in vitro assays have shown that cellular constituents of peripheral blood mononuclear cells(PBMC) can alter growth of carcinoma cell line. Author compared the effects of normal fibroblasts on squamous cell carcinoma cell line(SCL-1) along with those of sctivated and/or nonactivated PBMC on SCI 1 using a skin equivalent system. This system prevents direct cellular contact by growing SCL-1 on an overlying Millicell-HA membrane and normal fibroblast or supernatants of PBMC in a lower chamber. Normal fibroblasts enhanced the outgrowth of SCL-1 and induced a more organized phenotype of SCL-1. Supernatants from nonstimulated PBMC suppressed outgrowth of SCL 1, and concanavalin A stimulated PBMC supernatants alterd rnorphology of cultured SCL-1 from a disorganized phenotype to a more organized phenotype. It is concluded that fibroblasts and PBMC may affect the growth and differentiation of SCL-1 via their mediators(cytokines)

전계방출을 위한 고종횡비 투명 팁 어레이 제작

이창화(Chang Hwa Lee),이석우(Seok Woo Lee),이승섭(Seung Seob Lee) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.5