Delayed Hydride Crack Velocity of Zirconium Alloys with the Direction of an Approach to Temperature

KIM, Young Suk,KIM, Kang Soo,CHEONG, Yong Moo Atomic Energy Society of Japan 2006 Journal of nuclear science and technology Vol.43 No.9

<P>The delayed hydride cracking (DHC) tests were conducted on Zr-2.5Nb compact tension specimens with the test temperatures reached by a heating and a cooling. The Zr-2.5Nb specimens were either furnace-cooled or water-quenched after a hydrogen charging treatment to contain 10 to 100 ppm H. On an approach to the test temperatures by a cooling, both the Zr-2.5Nb specimens showed the DHC velocity increasing with an increasing temperature over a temperature range of 100–300°C, irrespective of the cooling rate. However, on an approach to the test temperatures by heating, the furnace-cooled Zr-2.5Nb showed a DHC arrest at temperatures over 180°C and no DHC at 250°C, and the water-quenched ones did have a DHC growth, even at 250°C. Using Kim’s DHC model we elucidate the DHC arrest in the furnace-cooled Zr-2.5Nb at temperatures over 180°C and the DHC growth in the water-quenched specimen, even at 250°C, upon an approach by a heating.</P>

Cisplatin과 Tobramycin이 白鼠 Corti器에 미치는 영향에 關한 電子 顯微鏡的 硏究 : Ultrastructural Study

김동환,신태균,김무강,김홍선,김원식 충남대학교 의과대학 지역사회의학연구소 1989 충남의대잡지 Vol.16 No.1

In order to study the morphological changes of Corti’s organ in the rat treated with cisplatin and tobramycin, thirty-three rats, weighing between 200∼250g, were used, and divided into 4 groups, i.e., 3 rats were used for control, and 30 rats were used for 3 experimental groups. Each experimental group was divided into cisplatin-treated, tobramycin-treated, and both cisplatin and tobramycin treated group with 10 rats. Rats were injected with a single dose of 7.7㎎/㎏ of cisplatin intraperitoneally and 50㎎/㎏/day of tobramycin for 2 days intramuscularly, respectively or both. Treated rats were sacrificed on the 3rd and 5th day after the first injection. Results were as follows; 1. Cisplatin-treated group: Outer hair cells of Corti’s organ were degenerated with the formation of vacuoles and appearance of lysosomes, however, inner hair cells showed mild vacuolization. 2. Tobramycin-treated group: NO pathological changes were found in Corti’s organ. 3. Combined cisplatin and tobramycin treated group: Outer and inner hair cells showed vacuolization, appearance of lysosomes, myelin figures and multivesicular body. There were also multivesicular body in the inner phalangeal cell and myelin figure in the Reissner’s membrance. 4. Degeneration of Corti’s organ in the combined treated group was more sever than those of the single cisplatin-treated or tobramycin-treated group. 5. NO pathological differences of Corti’s organ in duration of postinjection were manifested in any groups. It can be concluded that cisplatin induces toxicity to inner ear and cisplatin enhance toxicity more in continued treated with tobramycin.

Mirizzi 증후군의 변형된 분류와 치료

김형철,강길호,채만규,김성용,백무준,이문수,박상흠,이문호,김창호,송옥평,조무식,박희주 순천향의학연구소;Soonchunhyang Medical Research Institute 2000 Journal of Soonchunhyang Medical Science Vol.6 No.1

Purpose : The Mirizzi syndrome is relatively rare and preoperative diagnosis of this disease is difficult. In 1978, Morelli suggested the subclassification of the Mirizzi syndrome into acute or chronic form. We experienced 5 cases of acute form. We analysed clinical features, preoperative radiologic findings and operative findings of 18 cases including acute forms which were diagnosed as Mirizzi syndrome and should suggest the modified classification of Mirizzi syndrome for choice of appropriate treatment. Method : From January 1995 to December 1998, 18 cases, of which 8 cases were diagnosed at Soonchunhyang University Chunan Hospital, and 10 cases were reported in the Korean Journal were retrospectively analysed with regard to clinical features, preoperative radiologic findings and operative findings. According to the clinical features, whole cases were divided into type Ⅰ(acute form) and type Ⅱ(chronic form) and then each type of cases were subclassified according to preoperative radiologic findings and operative findings. Results : Of 18 cases there were 5 cases in type Ⅰ(27.8%), 13 cases in type Ⅱ(72.2%). Type Ⅱb was most common. Type Ⅰa cases were treated only with cholecystectomy. We applied cholecystectomy, T-tube choledochostomy and patch technique in type Ⅰb and thpe Ⅰc cases. Cholectystectomies including removal of gallstones and internal drainage procedures were done in type Ⅱ chronic forms. Conclusion : The acute form(Type Ⅰ) of Mirizzi syndrome was suggested by Morelli might be subclassified into typeⅠa,Ⅰb and Ⅰc following the presence of the necrotic defect in common hepatic duct. Through the modified classification of Mirizzi syndrome based on clinical feature, preoperative radiologic findings and operative findings, we can choice appropriate treatment.

증점제를 사용한 고유동콘크리트의 기포조직과 내동해성에 관한 실험적 연구

김무한,권영진,강석표,여동구,김용로,장종호 충남대학교 산업기술연구소 2000 산업기술연구논문집 Vol.15 No.1

Recently, lots of studies for high flowing concrete have been suggested under practical use that it is only a way to solve the confronted problem. However, most studies have been concentrated on the manufacture method and properties of fresh concrete, but there is few studies for the durability of hardened concrete, specially for the freezing and thawing. It is generally known that the frost resistance of concrete is much affected by the air content in concrete and by the air void system. The frost resistance is also believed to vary with the strength of concrete. The purpose of this experimental study is to make a comparison between high flowing concrete using viscosity agent and ordinary concrete about the effect of the viscosity agent, air content and curing method on the frost resistance. As the result of tutus study, the frost resistance have not effect the viscosity agent but effect the different of curing methods.

한국무용연기력과 체력요소와의 관계에 대한 연구

김무영,강현숙 全北大學校 敎育大學院 1999 敎育論叢 Vol.19 No.-

The purpose of this study is to provide the information whether Korean dance improves the physical fitness and which factors should be reinforced and improved too get a better performance on the assumption that performance has something to do with physical fitness. The subjects were 25 females who were majoring in Korean dance in W University. They were divided into 3 groups according to the level of performance. Each group took a test which measured 6 physical fitness factors so as to compare each group's physical fitness. The results of analysis were as follows : 1. The flexibility (P<0.1) was the only factor that affect the performance of Korean dance. The other factors came power, muscular endurance, agility, strength, and balance in order. Ragression Equation for correlation between performance score and flexibility is : Performance score = 64.4 + 0.0181 (forward trunk flexion)^2. 2. In the correlation between performance score and physical fitness factors, only flexibility showed a little relation(r=0.33). 3. The flexibility showed significant difference in comparison with physical fitness between groups according to the level of performance (P<0.1). In conclusion, it was flexibility among physical fitness factors that affect the performance of Korean dance.

소 卵胞의 體外培養에 의한 卵子의 體外成熟과 體外受精에 관한 硏究

金相根,南潤伊,山根倫子,金武剛 충남대학교 수의과대학 동물의과학연구소 1997 動物醫科學硏究誌 Vol.5 No.-

This study was to investigate the effects of the follicular culture from which the oocytes origenate on their subsequent in vitro maturation. The follicular oocytes were cultured in TCM-199 medium containing FCS, hormones, BFF for 24-30 hrs in CO^2 incubator with 5% CO^2 in air at 38.5℃ and then matured oocytes were again 18-20 hrs with motile capacitated spermatozoa in the BO solution containing 100 ㎍/㎖ of heparin. The results obtained in these experiments were summarized as follows : 1.Ovarian follicles were isolated and cultured according to size 1-2 ㎜, 2-4 ㎜, 4-6 ㎜ and 6-8 ㎜ for 24-30 hrs. The rates of GVBD in each group were 80.0%(40/50), 84.4%(38/45), 77.8%(35/45) and 84.0%(42/50), but oocytes maturation were supressed at anaphaes-Ⅰ or telephase-Ⅰ stage. 2. When oocytes cultured for 4 hrs at 35℃ in medium with BFF and hormones after follicular culture for 24-30 hrs, the maturation completed to metphase-Ⅱ stage. However, rates of GVBD in oocytes from follicular culture were higher than oocytes cultured in medium. 3. When oocytes from follicle cultured for 4 hrs at various temperature and culture time were cultured for 24-30hrs the rates of oocytes maturation from follicle cultured at 20℃(43.6%, 24/55), 30℃(47.3%, 26/55) and 35℃(52.7%, 29/55) were significant higher than group cultured at 4℃(24.4%, 11/45). 4. When oocytes from follicles cultured for hrs at 35℃, the rates of oocytes maturation and fertilization rates were 67.3%(101/150), 29.3%(44/150) and oocytes cultured for 24-30hrs at 35℃, thr rates of oocytes maturation and in vitro fertilization were 86.5%(122/141), 53.9%(76/141), respectively.

한국산야생등줄쥐(Apodemus agrarius coreae)의 해마복합체에서 neuropeptide Y 면역반응세포에 관한 연구

김무강,송치원,이경열,박일권,정영길,이강이,김종섭 충남대학교 수의과대학 동물의과학연구소 1997 動物醫科學硏究誌 Vol.5 No.-

Neuropeptide Y(NPY) was first isolated from porcine brain. This discovery has lead some workers to study the distribution of this peptide in the central nervous system of various mammals. In this study the distribution pattern of neuropeptide Y-immunoreactive neurons was examined in the hippocampal complex of Striped field mouse in Korea(Apodemus agrarius coreae) Experimental animals were anesthesized with thiopental sodium and perfused with 4% paraformaldehyde through the left ventricle and the ascending aorta. The brains were removed and transferred 10%, 20% and 30% sucrose solution. Sections were cut on a cryostat into 40㎛-thick. The tissue was immunostained with free-floating and avidin-biotm complex(ABC) method. The results obtained in this study were summarized as followings. 1. The most of NPY-IR neurons in hippocampus proper were found in the polymorphic layer and a few was found in the pyramidal layer. 2. The process run vertically in the deep polymorphic layer and run parallel to corpus callosum in superficial polymorphic layer. 3. The shapes of neurons in hippocampus proper were varied of polymorphic, oval or round, and the nerve fibers were found in the molecular laver and the hippocampal fissure. 4. The highest density in number of NPY-IR neurons on dentate gyrus were found in hilar area of dentate gyrus. 5. The most of NPY-IR nerve fibers were found in molecular cell layer.

MgCl₂溶液內에서 STS 304 HP Stainless Steel 熔接部의 破壞擧動에 對한 硏究

金永奭,丁太權,朴昌彦,洪錫柱,梁仁榮,金基玉,朴煥奎,李茂錫,曺圭宰,鄭在康 조선대학교 생산기술연구소 1983 生産技術硏究 Vol.1983 No.-

This paper is based on an experiment analysing the stress corrosion cracking behaviour of welding specimens compared to that of non-welding specimens of STS 304 HP stainless steel in corrosion solution. As a corrosion condition, stainless steel has been known to be the most fragile in a solution of 42% MgCl₂heated to the boiling point, therefore the experiment was carried out in this condition. The experiment was carried out with argon gas TIG welding specimens and non-welding ones made of stainless steel plates, thickness 2mm, by tensile force. At this time, the tensile force was taken to be the value of the yield strength of the tensile test specimens divided by the safety factor of 3.0 to 3.5, 4.0, 4.5, and 5.0. In this paper, the relations between Time of Initial Crack, Time of Failure, Time of Final Fracture and Crack Propagation Length were investigated and then plotted. Furthermore, the relations between Stress Intensity Factor K proposed by Irwin and the Time of Initial Crack, the Time of Failure, the Time of Final Fracture were calculated and plotted. At the last, all the relations plotted were expressed to normal equations by computer, and the equations were used to analyse the data obtained in the experiment. The conclusions obtained in this study are as follows: 1. Welding materials, compared with non-welding ones, as the Time of Initial Crack, the Time of Failure, and the Time of Final Fracture were generally very fast, appeared to be a phenomenon of unstable brittleness fracture. 2. Non-welding materials, compared with welding ones, as the safety factor was larger or the working stress was smaller, appeared to be a phenomenon that the longer had had greater durability. Therefor, welding materials must be considered enough to be used in heate affected and stress corrosion atmosphere. 3. The normal equations of the Time of Initial Crack and the variation rate to the same Stress Intensity Factor K are as follows: (A) Non-welding T =259702.4-5451.2 K+28.386 K² T = -5451.2+28.386 K (B) Welding T= -332.693+28.043 K-0.211 K² T' =28.043-0.211 K here, T; Time of Initial Crack, T'; Variation Rate of Time of Initial Crack to Stress Intensity Factor K, K ; Stress Intensity Factor.

저장 온도 및 상대습도가 비타민 정제 중 지용성 비타민 함량의 변화에 미치는 영향

김동섭,이재황,김세곤,이동언,박석준,이진희,이강표,최성원,백무열 경희대학교식량자원개발연구소 2007 硏究論文集 Vol.26 No.1

成長에 따른 肝細胞의 量的 變化에 關한 硏究

金武剛,金源式 충남대학교 의과대학 지역사회의학연구소 1987 충남의대잡지 Vol.14 No.1

To evaluate the morphological and functional changes of the hepatic cells of hybrid chick according to its growing stages, the volume of cytoplasm, nucleus and nucleolus were measured in 10 specimens of each group; the group of 2nd day, 14th day, 2nd month, 5th month and the group of 11th month after hatching. The results were as follows; 1. The volume of nucleus and nucleolus was increased from the 2nd day to the 14th day after hatching (actively growing period) and from the 5th month to the 11th month after hatching (the period of hypertrophy). The volume chage of cytoplasm appears oppositely to that of nucleus and nucleolus. 2. The nucleoplasmic index was increased at actively growing period and the period of hypertrophy, and the ratio of nucleolar volume to nuclear volume was increased at actively growing period, but unchanged at the period of hypertrophy.