Corrosion and Oxidation Resistance Behaviors of Ta-Containing Low Alloying Zirconium

Il‑Hyun Kim,Yang‑Il Jung,Byoung‑Kwon Choi,Hyun‑Gil Kim,Jae‑Il Jang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.8

Zirconium alloys are widely used to fabricate nuclear fuel claddings, and thus is desirable to improve the resistance of suchalloys to corrosion and structural instability. In this study, Ta was used as an alloying element to improve the corrosion andoxidation resistance of zirconium alloys. The model alloy (TaZL) contained 0.03 wt% Ta and other elements with a proportionof less than 1 wt% in total (0.1 wt% Nb, 0.4 wt% Fe, 0.2 wt% Cr) in a zirconium base. The corrosion test involving pressurizedwater at 360 °C and oxidation test involving steam at 1200 °C indicated that TaZL exhibited the lowest weight gains amongthose of compared conventional and advanced Zr alloys. The corrosion and oxidation resistances of TaZL were respectivelyimproved by 4 and 1.5 times compared to the corresponding values of Zircaloy-4. The microstructures of the oxide formedon TaZL were columnar along the oxide growth direction and did not change from columnar to equiaxed, which resulted inthe high resistance of the alloy to corrosion and oxidation.

초·중·고 학생들의 과학 태도 변화에 대한 학습환경의 원인 분석

권치순,허명,양일호,김영신 한국과학교육학회 2004 한국과학교육학회지 Vol.24 No.6

최근 학교교육에서 학생들의 과학 태도에 대한 관심과 중요성이 증대되고 있다. 학생들의 과학 태도는 학업 성취도, 교육 프로그램의 일관성, 수업의 질뿐만 아니라 과학 교육의 관점과 과학 관련 직업 선택에도 영향을 준다. 그 동안의 과학 태도에 대한 선행 연구와 국제 비교 연구에 의하면, 우리나라 학생들의 과학 태도는 점차 하락하고 있는 것으로 나타났다. 이 연구에서는 초ㆍ중ㆍ고 학생들의 과학 태도 변화 과정을 알아보고, 이에 영향을 미치는 학습 환경 변인을 밝히는데 그 목적이 있다. 초등학교 3학년부터 고등학교 2학년 학생 약 6,925명을 대상으로 2003년 3월부터 3회에 걸쳐 학생들의 과학 태도와 학습 환경 검사를 실시하였다. 분석 결과, 학생들의 과학 태도는 일년 중 6월 이후에 낮아지고, 초등학교 4학년에서 중학교 2학년까지 과학 태도가 크게 변하였다. 과학 태도가 1학기보다는 2학기에 더 많이 하락하였으며, 초?중학교 학생들보다 고등학생들의 과학 태도 하락 폭이 더 컸다. 학생들의 과학 태도에 가장 큰 영향을 주는 요인은 과학에 대한 경험이고, 교사, 학급 분위기 등이 과학 태도 변화에 영향을 주는 것으로 나타났다. 학습 환경 변인은 과학 태도가 하락한 학생과 과학 태도가 상승한 학생이 각각 다르게 영향을 주는 것으로 밝혀졌다. 과학 태도에 영향을 주는 범주는 초등학교에서는 성, 학년, 지역, 중학교에서는 학년과 지역, 그리고 고등학교에서는 지역으로 나타났다. The importance of science attitudes is more increasing in science education. Science attitudes may influence students' attainment, consistency and quality of classwork as well as their later views of science education and scientific occupations. According to the international comparative researches and longitudinal studies on Korean students' science attitudes, it has shown that the more grade, the less science attitude. This research was survey the science attitudes and learning environment variables, and then make a inquiry that causes of decline of science attitudes. To study this purpose, the participating students in this study will be selected from 3th to 11th grade. 6,925 participants were administered 3 times in questionnaires of science attitudes and learning environment variables during a year. The result of this study showed that science attitude got low after June. Science attitude was changed from 4th grade to 8th grade students. Science attitude much more decrease second semester than first semester, high school students' science attitude fell much. It was experience about science that cause the biggest effect in science attitude and other learning environment variables influence in science attitude change. Learning environment variables made different influence from students of increased and declined science attitude. As category that influence in science attitude, in elementary school were gender, area and grade, in middle school were grade and area, and in high school was area.

심혈관계질환으로 사망한 성인형다낭신 3예 보고

양경무,권일훈,조갑래,서중석 大韓法醫學會 1999 대한법의학회지 Vol.23 No.1

Adult polycystic kidney disease is a genetic disease characterized by bilateral multiple renal cysts and is transmitted as an autosomal dominant traits. The disease usually manifests in the fourth decade of life. The affected patients usually die with end stage renal failure, cardiovascular assaults and infection etc. Cardiovascular assaults include ruptured berry aneurysm, spontaneous intracranial hemorrhage, acute myocardial infarction, dissecting aortic aneurysm and hypertensive heart failure. Fatal intracranial hemorrhage and hypertensive heart failure occur in 15% and 2% of patients, respectively. Genetically-dater-mined structural weakness in the arterial wall have been suggested as a possible factor in the genesis of berry aneurysm. We have experienced three autopsy cases with cardiovascular causes of sudden death. Two cases have intracranial hemorrahage (1 berry aneurysm and 1 intracerebral hemorrhage) and the remaining one is dead with hypertensive cardiomyopathy. All of them are aged over 40 years and associated with polycystic liver disease. Histologically, myriad cysts of enlarged bilateral kidney are lined by single layer of cuboidal cells with focal hyperplastic epithelial configuration. Diffusely scattered liver cysts are also lined by flat to cuboidal epithelium and often associated with portal fibrosis.

만성부비동염 환자에서 부비동 단순 X-선 사진과 전산화 단층(CT) 사진 소견의 비교

선동일,윤선호,신민호,서병도,양일권 釜算慶南耳鼻咽喉科學會 1993 임상이비인후과 Vol.4 No.1

전립선암의 예측인자로서 전환대 전립선특이항원의 유용성

김현학,권동득,오봉렬,박광성,류수방,박양일 全南大醫大 2001 전남의대학술지 Vol.37 No.3

간질발작을 주 증상으로 하는 회백질 이소증을 동반한 Schizencephaly 1례

신석호,양일권,김제헌 大韓神經精神醫學會 1991 신경정신의학 Vol.30 No.4

We experienced a case of schizencephaly with heterotopic gray matter that was only manifested a seizure attack. The clinical manifestation of this patient was only seizure without mental retardation, which was controlled by anticonvulsants. The term schizencephaly was introduced by Yakovlev and Wadsworth in 1946 to describe bilatral, nearly symmetrical and full-thickness clefts, which were characterized by an infolding of cortical gray matter along the clefts. The most widely accepted theory for the pathogenesis of this anomaly is the failure of formation of a segment of the germinal matrix or segmental failure of neuronal migration. Heterotopic gray matter is frequently found within and near the cleft. Patients who have these condition present clinically with seizures and developmental delay, and abnormal motor skills are noted in the more severly affected cases. Recognition is important for planning proper treatment and for genetic counseling.

재래(흑색) 염소의 비육에 관한 연구 : Ⅰ. 일측 갑상선 제거가 체중, 체온 및 맥박에 미치는 영향 Ⅰ. Effect of Uni-lateral Thyroidectomy on Body Weight, Body Temperature and Pulse Rate

박무현,권해병,양일석 慶尙大學校 1975 論文集 Vol.14 No.-

In order to investigate the relationship of body weight, body temperature and pulse rate to hypothyroidism in the state of uni-lateral thyroidectomy of Korean native goat, a brief observation was carried out. Twenty healthy male adult goats (7 months old) were used in the present experiment dividing into 2 groups, the control with 5 and the experimental with 15, respectively. Individuals of the experimental group were received uni-lateral thyroidectomy by surgical operation, while individuals of the control group, on the other hand, were received sham-operation. Measurements of body weight, body temperature and pulse rate after the operation were performed in duration of 48 days by 2 days interval. The results obtained could be summerized as follows. 1. There were no significant changes in body weight of experimental group compared to that of control group. 2. Uni-laterally thyroidectomized goat showed no changes in body temperature, which is seemed to he doe to a compensatory effect. 3. Statistical calculation did not show any difference in pulse rate between control and experimental group. The present experiment can he concluded that uni-lateral thyroidetomy had not any effect on the changes body weight, body temperature and pulse rate.

창업보육센터 입주기업의 특성과 창업보육서비스에 따른 기업성과 분석

이충섭,정양헌,최수일,권철홍 대한경영학회 2003 大韓經營學會誌 Vol.16 No.7

This study is focused on the characteristics of firms in business incubators and relationship of firms' performance and incubating services. Ninety-three firms in the business incubators of universities and research institutes were surveyed and their market/technology environment, performance, and incubating services received were evaluated from their point of view. Data were then, analyzed to find out necessary factors for operating the incubation centers efficiently and providing appropriate incubating services for the business performance of firms in the centers. Firms in the incubation center are very optimistic to their business opportunity and alleged to be positive about their successful business future. With their business performance, firms are generally satisfied and try to increase the performance by having product related and technological advantage. On average, firms evaluate their performance in financial and internal processing aspect aspects lower than performance in customer and innovation aspect. Although firms are generally satisfied with the incubating service they received from the center, they seem to need more specific and customized services for their own business purpose. It is, therefore, suggested that incubating services are evaluated and necessary services are developed based on firms' needs in order to improve firms' overall satisfaction with services from the incubation center. It is also suggested from this study that market/technology environment, business performance, and incubating service characteristics of firms in the incubation centers are associated each other and need to be analysed all together.

조루증의 치료에서 Paroxetine의 효과와 부작용

박광성,이재규,윤진상,권동득,오봉렬,류수방,박양일 全南大醫大 2001 전남의대학술지 Vol.37 No.1

A New Method of Liver Size Estimation on Hepatic Scintigram : Hepato-abdominal Ratio

Yang, Il Kwon,Park, Seog Hee,Yoon, Sung Do,Bahk, Yong Whee CATHOLIC MEDICAL CENTER 1982 Bulletin of the Clinical Research Institute Vol.10 No.1

Estimation of liver size is essential in the diagnosis of liver disease. We carried out the present study to determine the normal upper limit of relative liver size by means of hepato-abdominal ratio. We measured liver size using 4 linear diameters of the liver and, as the reference, the abdominal transverse diameter (the distance from the right margin of the liver to the left margin of the spleen) was measured. Hepato-abdominal ratio was calculated by dividing the diameters of liver with the abdominal transverse diameter. The hepato-abdominal ratio using the midline vertical diameter is 0.43±0.06 in the normal group and 0.53±0.07 in the hepatomegaly group. It seems warranted to suggest hepatomegaly when hepato-abdominal ratio using the midline vertical diameter is 0.5 or more in the interpretation of hepatic scintigram. Various linear measurement of the liver in the normal and hepatomegaly group were evaluated and the concept of the hepato-abdominal ratio was introduced as a new reliable criteria of liver size estimation. 1. The smallest value was recorded with the midline vertical diameter. It was 4.2±0.4 cm in the normal group and 5.0±0.6 cm in the hepatomegaly group. 2. The diameter using other methods ranged from 5.6 to 7.2 cm in the normal group 'and 6.3 to 7.5 cm in the hepatomegaly group. 3. There was significant difference in the hepato-abdominal ratios between the normal and hepatomegaly group. 4. The hepato-abdominal ratio using the midline vertical diameter was 0.43±0.06 in the normal group and 0.53±0.07 in the hepatomegaly group. Among various hepato-abdominal ratios, the ratio of the midline vertical diameter/the transverse abdominal diameter was most significantly different between the normal nand hepatomegaly group. 5. The 99% tolerance limits of the hepato-abdominal ratio using the midline vertical diameter was 0.41-0.45 in the normal group and 0.51-0.55 in the hepatomegaly group. 6. It was warranted in the interpretation of hepatic scintigram to suggest hepatomegaly when the hepato-abdominal ratio using the midline vertical diameter is 0.5 or larger.