1Cr-0.5Mo 강 용접부 균열의 고온파괴거동 연구

이해무,윤기봉,신규인,최현창,박재학 한국산업안전학회 1997 한국안전학회지 Vol.12 No.2

Fracture behavior of ex-serviced 1Cr-0.5Mo steel was measured at room(24℃) and elevated(538℃) temperature and compared with that measured with virgin 1Cr-0.5Mo steel. Compact C(T) specimens were machined from the base and welded test materials. In case of the C(T) specimens of the weld, fatigue precrack was introduced along the fusion line so that following crack growth should occurs along the region of heat affected zone. It was observed that the J-R curve of the serviced material was significantly lower than that of the virgin material at room temperature. Brittle fracture was observed in the serviced material. On the other hand, at elevated temperature no noticeable difference was found between the J-R curves of the virgin and the serviced material. The measured J-R curves were also compared with those of the 1.25Cr-0.5Mo steel obtained from the other literatures. Optical microscopy and SEM examination of the serviced material reveal the carbide in/along the grain boundary which shows material degradation due to long-term usage. An example of application of the measured J-R curves is shown.

R 곡선상의 안정균열개시점 결정을 위한 수정옵셋방법

안광주,최재강,박준수 한국산업안전학회 1999 한국안전학회지 Vol.14 No.3

This paper were performed to evaluate the elastic-plastic fracture toughness J_(IC) by the unloading compliance method for 1/2 CT specimen of A5083-H112 aluminum alloy. A modified offset method for negative crack growth effect is presented and compared with Voss offset method. We found that the modified offset method presented can be used efficiently for a determination of the stable crack onset. The J_(IC) by Voss offset method can be overestimated, but the suggested offset method showed a high reliability within 5% of tolerence from the results by the multi-specimen method.

당뇨병에서의 혈장 Renin 활성에 관한 연구

이정상,이문호,김성권,최강원,표희정,박정식 대한핵의학회 1979 핵의학 분자영상 Vol.13 No.1

당뇨병에서의 고혈압 및 신합병증에 따른 Renin Angiotensin-Aldosterone계의 동태를 밝히기 위하여 40예의 당뇨병 환자에서 기저 및 furosemide 정주 2시간 후의 PRA를 측정하였다. 1) 40예의 당뇨병 환자는 신합병증과 고혈압의 유무에 따라 4군으로 분류하였으며, 임상적인 합병증이 없는 Ⅰ군에는 15명, 신합병증이 있는 Ⅱ군에는 7명, 신합병증과 고혈압이 같이 있는 Ⅲ군에는 8명, 고혈압만 있는 Ⅳ군에는 10명의 환자가 속하였다. 2) 각 군의 24시간 요중 Na배설량의 평균치 사이에는 유의한 차이가 없었다. 3) 기저 PRA치는 Ⅰ군이 1.53±1.09ng/ml/hr(Mean±S.D), Ⅱ군이 0.63±0.59ng/ml/hr, Ⅲ군이 0.79±0.62ng/ml/hr, Ⅳ군이 1.11±0.80ng/ml/hr로서 Ⅱ군과 Ⅲ군은 Ⅰ군에 비하여 유의하게 저하되어 있으나(P$lt;0.05), 다른 군들 간에는 유의한 차를 볼 수 없었다. 4) furosemide 정주 2시간 후의 PRA치는 Ⅰ군이 2.72±1.96ng/ml/hr, Ⅱ군이 0.92±0.78ng/ml/hr, Ⅲ군은 1.03±0.76ng/ml/hr, Ⅳ군은 1.73±1.39ng/ml/hr로써 Ⅰ군과 Ⅱ군사이에서만 유의한 차이를 보이고(P$lt;0.05), 다른 당뇨병 환자군 사이에서는 유의한 차를 볼 수 없었다. 5) furosemide 정주에 의한 Renin 분필 자극시험에 대한 반응도 Ⅱ군과 Ⅲ군에서는 둔화되어 있는 양상을 보이나, 시험대상도 적고하여 통계적 유의성에는 미치지 못하였다. 이상의 성적에서 신합병증이 있는 당뇨병에서는 혈장 Renin활성이 저하되며 furosemide 정주에 의한 Renin 분필자극시험에 대한 반응도 둔화됨을 알 수 있었다. 또한 당뇨병성 신합병증에 의한 고혈압에서도 혈장 Renin활성은 저하되는 경향을 보여서 이 경우의 고혈압은 Renin이외의 다른 요인이 작용할 것으로 보인다. To evaluate the renin-angiotensin-aldosterone system in diabetes mellitus, basal plasma renin activity(PRA) and its response to intravenous furosemide were determined in 40 diabetic subjects. The diabetics were divided into 4 groups according to the pressence of nephropathy and/or hypertension. Uncomplicated diabetics(Group I) were taken as control group and the results of the other groups were compared to this group. In diabetics viith nephropathy alone(Group Ⅱ), and with nephropathy and hypertension (Group Ⅲ), basal PRA values were 0.63±0.59ng/ml/hr., and 0.79±0.62ng/ml/hr., respectively, both significantly lower than control group. (1.53±1.09ng/ml/hr.). (P$lt;0.05) In both of the above groups, the responses to intravenous furosemide tended to be blunted. On the other hand, in diabetics, with hypertension only (Group Ⅳ), the basal and stimulated PRA were not significantly different from control. Above results suggests that nephropathy may be one of the factors which suppress renin activity in diabetes me.

RIHSA와 131I-Hippuran으로 측정한 심박출량의 비교

김정일,고창순,이안기,길광수,박진영,김동섭 대한핵의학회 1970 핵의학 분자영상 Vol.4 No.2

저자들은 정상성인 남자 11예에서 방사성동위원소인 RIHSA와 (131)^I-Hippuran을 사용하여 체외계측법에 의한 심박출량을 측정하여 다음과 같은 결론을 얻었다. 1) RIHSA를 사용한 심박출량의 측정치는 6750±866ml/min, 심계수의 측정치는 3960±476ml/min./㎡이었다. 2) 131I-Hippuran을 사용한 심박출량의 측정치는 5940±764ml/min, 심계수의 측정치는 3490±396ml/min./㎡이었다. 3) (131)^I-Hippuran에 의한 심박출량의 측정치는 RIHSA를 사용한 심박출량의 측정치의 88%로 나타났으며 양자간의 차이는 통계학적의미를 가지고 있었다(P$lt;0.05). 4) (131)^I-Hippuran을 사용하여 심박출량측정이 가능함을 알 수 있었다. Repeated measurement of cardiac output in the same 11 normal individuals were done with (131)^I-Hippuran and RIHSA. Following results were obtained. 1) The cardiac output measured with RIHSA was 6750±866ml/min. 2) The cardiac output measured with (131)^I-Hippuran was 5940±764ml/min. 3) The relative value of cardiac output measured with (131)^I-Hippuran to that measured with RIHSA was 88 percent, and a statistical significance was found present in the difference.

Tropane Spirohydantoin들의 합성 및 구조분석

정대일,이도훈,송주현,이용균,최순규,박유미,한정태 동아대학교 환경문제연구소 2006 硏究報告 Vol.28 No.1

The tropane ring system is an important substructure in a number of natural products and synthetic compounds of biological and medicinal importance. As a result of the significance of the tropane ring system, the purpose of this study is the synthesis of anticonvulsant compounds of new s tructure anticipated anticonvulsant activity. After we first synthesized the various N-substituted nortropinone derivatives, we prepared new nortropane alkaloids and nortropinone derivatives. Substantially, we tried several experiments to optimize reaction condition. The tropane spirohydantoins 17, 18, 19, 20, 21 were respectively synthesized by the treatment of corresponding N-substituted nortropinone with potassium cyanide and ammonium carbonate.

Bhattacharya법에 의한 혈청 Ca, Zn, Mg, Cu의 정상치

김영기,서진태,박명희,김상인 대한병리학회 1981 Journal of Pathology and Translational Medicine Vol.15 No.3

급성 심근경색증 초기 진단에 latex 응집을 이용한 혈청 myoglobin 측정의 임상적 의의

박영배,서정돈,최윤식,이영우,오병희,손대원,임하진,김유우,박명희 대한내과학회 1987 대한내과학회지 Vol.32 No.2

We evaluated the diagnostic usefulness of latexagglutination test for elevated serum myoglobin as a screening test in the early phase of acute myocardial infarction and 21 patients with chest pain mimicking acute myocardial infarction were included in this study. Result was compared with serum myoglobin level measured by radioimmunoassay (RIA) in every case. The Following results were obtained: 1) When serum myoglobin levels measured by RIA below 85ng/㎖ were regarded as normal, this test showed sensitivity of 82%, specificity of 95%. 2) In latex-agglutionation test for elevated serum myoglobin, test results were interpreted as negative, weakly positive and positive. If we regard weakly positive tests as positive, sensitivity was 93% and specificity was 62%. In contrast, if we regard weakly positive tests as negative specificity rose to 100% while sensitivity reduced to 75%. 3) Agreement rate of both test was k=0.59. It is suggested that latex-agglutination test for elevated serum myoglobin is helpful in ruling out acute myocardial infarction when test result is negative, and that it can be used as a screening test in the early phase of acute myocardial infarction because of its rapidity and simplicity in performing the procedure.

당뇨병유발백서에서 급성패혈증 병발시 적혈구막지질과산화의 변화

박성우,홍성관,유형준,장대영,강승식,유재명,임성희,최문기,노정우,이규만 대한당뇨병학회 1994 Diabetes and Metabolism Journal Vol.18 No.3

인공판막 재대치험예에서의 판막실패의 양상

박영배,김유호,서정돈,최윤식,이영우,오병희,도문홍,최동주,전은석 대한내과학회 1987 대한내과학회지 Vol.32 No.3

In order to observe the aspects of prosthetic cardiac valve failure, we analyzed 26 cases of Redo operation among 1081 cases of valve replacemant performed from Jan. 1961. to July 1986. The results are as follows; 1) Crude Redo operation rate was 2.4%. 2) The most common cause or prosthetic cardiac valve failure was the primary tissue failure (73%) 8r the PVE was the 2nd (15.4%). 3) Mean valve implantation time was 47.7 months. Implantation time in the child group was shorter than in adult by 6.8 months, In the primary tissue failure group (19 cases) implantation time in the child was 42.8 months 8z in adult, 66.8 months. (P$lt;0.05) In conclusion, the durability of tissue valves was significantly decreased in the child age group because of increased propensity for calcification, so the preference of tissue valves especially in this age group should be reconsidered.

프로골프선수의 슬관절 등속성 근력에 관한 굴곡근과 신전근의 비교연구

박성태,정성태,정덕조,정영수,엄우섭,전태원,우재홍,박익렬 한국운동과학회 2000 운동과학 Vol.9 No.1

프로골프선수의 슬관절 등속성 근력에 관한 굴곡근과 신전근의 비교연구. 운동과학, 제 9권 제 1호. (201)-(209), 2000. 본 연구는 장기간의 골프운동이 슬관절의 단축성 굴근력과 신근력의 발달에 미치는 영향을 규명하여 경기력 향상을 위한 트레이닝 방법의 기초자료를 제공하고자 수행 되었다. 연구의 대상은 24명의 프로골프선수들(29.60±3.8세)로 골프경력은 12±1.7년으로 대상자 전원이 오른손을 주로 사용(우타)하였다. 측정은 등속성근력계(Cybex 770)를 이용하여 각속도 60°/sec와 180°/sec에서 3회씩 좌·우 교대로 측정하였다. 측정변인은 peak torque, peak torque 발현각, 평균파워, 총운동량 등이었다. 자료분석은 SPSS통계프로그램을 이용하여 실시하였으며 다음과 같은 결론을 얻었다.; 슬관절 굴곡근과 신장근의 좌·우 근력 비교에서 각속도 180°/sec로 굴곡성 운동시 총 운동량(total work)에서 좌·우측간에 유의한 차이가 있는 것으로 나타났으나(p<.05), 나머지 측정변인에서는 굴곡근과 신전근 모두 부하각속도에서 통계적으로 유의하지 않았다. 굴곡력의 경우 우측하지가 좌측하지에 비하여 높았으나 신전력의 경우 좌측하지가 다소 높은 경향을 보였다. 각 변인의 평균치에 대한 60°/sec와 180°/sec간의 비교에서는 모든 변인에서 통계적으로 유의한 차이를 나타내었다(p<.05). 슬관절 굴곡근의 신전근에 대한 비율(Flexor/Extensor Ratio)은 60°/sec에서 60%보다 낮게 나타났으나 좌·우측간 유의하지는 않았다. 결론적으로 다년간의 골프운동은 하지의 슬관절 근기능을 발달시키며 우측하지에 비해 좌측하지의 신전근에 더 많은 발달을 가져온다고 할 수 있다. A study on isokinetic concentric torque of kee extensor and flexor in golf players. Exercise Science, 9(1): 201-209, 2000. The purpose of this stydy was to investigate the effect of long therm golf exercise on isokinetic concentric torque of kee extensor and flexor. The subjects of this study were 24 men progolf players(29.60±3.8yrs) who have experience of 12±1.7yrs golf exercise and use mainly a right hand. The measurement was performed by use of Cybex 770 in angular velocity 60˚ /sec, 180˚ /sec and 3 repetitions. The variable of measure were peak torque, angle of peak torque, average power, total work and so on. The result of this study were as follow: There only was statistical difference between both low limb in Total work of knee flexor in angular velocity 180°/sec(p<.05) but not in other variables in both angular valocity. Right low limb was little stronger than reft low limb in flexor but there was opposite result in extensors. There was statistical difference between 60°/sec and 180°/sec in all varible. Knee flexors and extensors ratio was lower than 60% in angular velocity 60°/sec but there was no statistical difference between right and left low limb. It might be concluded from the test that long term golf exercise strengthen muscle function of knee flexors and extensor and left knee extensors more strengthen than right knee extensors.