Mechanical Characterization of Nano-Structured Materials Using Nanoindentation

( Ju Young Kim ),( Sung Hoon Kim ),( Jung Suk Lee ),( Kyung Woo Lee ),( Dong Il Kwon ) 대한금속재료학회 ( 구 대한금속학회 ) 2006 METALS AND MATERIALS International Vol.12 No.3

The principal strengths of the nanoindentation technique, which is used extensively to measure the mechanical properties of nano/micro materials, are easy sample preparation and simple experimental method. Hardness and Young`s modulus are essential properties measured by nanoindentation; hardness corresponds to resistance to plastic deformation whereas Young`s modulus is related to elastic deformation. Two key difficulties arise in association with nanoindentation on small volumes: measurement accuracy and material response. Here we discuss the indentation size effect (ISE) considering tip bluntness and variation in hardness of nano-multilayers with a bilayer period, representative research on measurement improvement, and material response at nanoscales.

젊은 남자 성인의 칼슘과 철의 영양상태에 관한 연구

박영숙,곽주영,권지혜,류화라 순천향대학교 기초과학연구소 2002 순천향자연과학연구 논문집 Vol.8 No.1

A survey was performed to 174 male young men who were living alone(40 persons) and shared living with friends(4143 persons) in Chungnam province. Their average age was 22.6 years old, height 171.8 ㎝, and weight 65.6 ㎏. Their daily calcium intake level was averaged 271.9±169.1 ㎎, which was 38.8 %RDA. Comparing calcium intake of each mealtime, breakfast, lunch, dinner, and snacks were composed of 18.6%, 30.0%, 34.0% and 17.4%, respectively. Their daily iron intake level was averaged 8.9±10.8 ㎎, which was 74.3 %RDA. Comparing iron intake of each mealtime, breakfast, lunch, dinner, and snacks were composed of 15.4%, 33.6%, 36.3% and 14.7%, respectively. These results suggested that deficiency of the two minerals in young male adults were severe and the nutrient qualities were also poor, no matter of their living alone or with accompanies. The deficiency was more profound in calcium than iron. And we observed iron nutriture differed significantly according to their living status, such as iron intake and its %RDA were significantly worse in single living subjects than the others. However calcium did not show significant difference. We concluded that shared living environment in young male adults could possibly improve their dietary mineral intake levels.

장기간 항갑상선제 투여 후 임의 중단 뒤 재복용시 발생한 무과립구증 1 예

김승만;김태영;박수영;배영환;서영경 정은주;김태균;권민정;박정현;이순희 인제대학교 2011 仁濟醫學 Vol.32 No.-

Agranulocytosis, one of the major side effects of antithyroid a gents, probably occurs in less than 0.25% of cases treated with antithyroid agents. It usually occurs within the first several weeks or months after the initiation of therapy, when drug dosage is higher. Most reported cases of agranulocytosis have occurred during the first 3 months of therapy. We describe here a rare case that did not experience the side effect for 6 years of antithyroid agent treatment but presented with agranulocytosis in one month after re-exposure. It suggests that the major side effect such as agranulocytosis can occur in patients who had undergone prior uneventful antithyroid drug therapy.

4종의 식품 부패 미생물에 대한 국내산 자생 식물 열매 추출물의 항균성 탐색

권민경,이해은,박주연,한영숙 동아시아식생활학회 2003 동아시아식생활학회지 Vol.13 No.5

To select new useful domestic plants with antimicrobial activities, thirty five samples of berry plant were distributed from Plant Diversity Research Center in Korea Research Institute of Bioscience and Biotechnolog. Their extracts with methanol were tested against Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, Listeria monocytogenes by paper disc method. The methanol extracts from Viburnum dilatatum, Viburnum erosum, Aralia continentalis, Camellia japonica, Acer trumcatam, Arasaema takesimense and Rhysocarpus intermedius were effective against S. aureus and the results were as follows: Viburnum erosum 6.5 ㎜, Viburnum dilatatum and Aralia continentalis 7.0 ㎜, Rhysocarpus intermedius 8.0 ㎜, Acer to mcatum 9.0 ㎜, Camellia japonica and Arisaema takesimense 9.5 ㎜ And only the methanol extract from Camellia japonica was effective against L. monocytogenes, 7.0 ㎜. Antimicrobial activities of E. coli and S. typhymurium were not detected. The minimum inhibitory concentration(NIC) of berry of Camellia japonica was examined as 1,250 ㎍/mL against S. aureus and as 1,250 ~ 2,500 ㎍/mL against L. monocytogenes.

體型의 肥滿過度와 人性의 相關性 硏究

權永玉,元周淵 忠南大學校體育科學硏究所 1985 體育科學硏究誌 Vol.3 No.1

This study was performed to see whether the extent of body thickness show the correlation with personality, for this study, 121 Chung Nam National University woman students were randomly selected. The results were summarized as follows. 1. Woman students generally have the good personality in daily life, but have little planing performance and practice. 2. There is significant relationship between the positive tendency in personality and a sense of responsibility, and no significant relationship between the positive tendency in personality and a sense of responsibility, and no significant relationship between the positive tendency and an attitude of composure, readiness, planing performance, the extent of social activities in campus. 3. There is no significant relationship between the growth of thickness of human body and the positive tendency, a sense of responsibility, and attitude of composure and readiness. 4. The corpulent body type in volumn show the more affirmative reaction in personality than selender body type.

벼 담수산파 재배시 파종량·질소분시·물관리 방법의 차이가 생육 및 수량성에 미치는 영향

권영립,권석주,조승현,최동철 원광대학교 2005 論文集 Vol.35 No.-

This study was carried out to investigate in connection with seeding rate according to the fertilizer application method and water management in direct seeding on flooded paddy surface. The total nitrogen and chlorophyll contents was decreased as increasing amount of seeding. The total nitrogen and chlorophyll contents were high in the strong drainage methods than the custom water management. LAI and dry mater recording where the seeding amount will increase to the fertilizer application method it increases consequently were low tendency from the site which omits the omitted the top dressing at tillering stage. The number of panicles per square metre was increased according to amount of seeding, but the number of spikelets per panicle was decreased. When omitted the top dressing at tillering stage and increasing the amount of seeding, the rice yield was high and amount of seeding was 89 kg per hectare. The results indicate that increasing of seeding rate and omission of fertilizer application with strong drainage at tillering stage was to reduce field lodging degree, to economy of water culture and to save labor for fertilization.

Alkylhalide가 Mouse의 LDH isozyme 분포에 미치는 영향 : Cellulose Acetate Electrophoresis Method

권미경,김영옥,박은주,이동화,이명미,이문희,이양자 曉星女子大學校 藥學大學 學生會 1988 曉星藥誌 Vol.4 No.-

The effect of Carbontetrachloride administration on Lactatedehydrogenase isozyme patterns were analyzed by cellulose acetate electrophoresis for the brain, heart, kidney, lung, liver and mouse muscle. Each other tissue was found to have a characteristic distribution of these isozymes. At normal condition, aerobic tissue such as brain, heart, kidney, and lung were found to have all five isozymes from LDH_1 to LDH_5, while anaerobic tissues such as liver and muscle were found to have superiorly LDH_5 The toxicity of Carbontetrachloride administration was most prominence in the liver, and lung toxicity was occured also.

벼 상온 저장 시기별 쌀 품질 변화

권석주,송영은,권영립,이덕렬,조승현,최동철 원광대학교 2005 論文集 Vol.35 No.-

Increasing concern about a rice quality, it is considered postharvest technology as well as cultivation management as an important factor. Therefore it is necessary to find optimal drying, storage method that did not affected a rice quality. In order to find the optimum storage period of rice, the rice quality was investigated during storage period. The temperature and humidity of storage bin were greatly changed but those of rice were a little do. The germination rate was slowly decreased as the storage period is long. The content of moisture was affected by a room temperature, it was increased at stored rice in rainy season(10-Jul~20-Jul). As storage period is long, the content of amylose, fatty acidity were a just Little changed but did not showed a constant tendency to it. The content of protein was increased and mechanic palatability value was decreased during storage period. The chromaticity of milled rice showed a range of lightness(L); 75.15~71.75, redness(a); 0.21~0.91, yellowness(b); 16.78~19.28 during storage period.

Cyclodextrin Glucanotransferase와 Cyclodextrinase를 생산하는 Bacillus 속 세균의 분리와 그 효소들의 특성

권현주,남수완,김광현,곽영규,김병우 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.3

토양으로부터 CGTase와 CDase를 함께 분비·생산하는 내열성 세균을 분리하였으며, 동정결과 Bacillus stearothermophilus로 판명되어 KJ16으로 명명하였다. Bacillus stearothermophilus KJ16 균주는 회분배양할 경우 2단계 성장을 하며 일차증식기에 CGTase를 생산하고 이차증식기에 CDase를 생산하는 양상을 보였다. 배치 pH를 7.0으로 조절하면서 배양할 경우, CGTase는 균의 증식에 따라 증가하고 CDase는 CGTase보다 뒤에 생산되었다. 그 생산양은 pH 비조절 배양에 비해 CGTase는 최대 12배(1300 mU/ml)까지, CDase는 2배(225 mU/ml)정도 증가되었다. 분리균주가 생산하는 CGTase는 분자량이 65,000 dalton으로 pH 6.0, 60℃에서 최적활성을 보이며 HPLC 분석을 통해 α-, β-, γ-CD를 42: 46: 12의 비율로 생산하는 α/β 혼합형 CGTase였다. 또한 CDase는 분자량이 68,000 dalton으로 pH 6.0, 55℃에서 최적활성을 보이며 최적기질은 γ-CD였다. A bacterium named as Bacillus stearothermophilus KJ16. The growth of the isolated strain occurred in two steps, and syntheses of CGTase and CDase were dependent on the growth cycle of the cell. CGTase was constitutively synthesized during the 1st growing phase, while CDase was synthesized inducibly during the 2nd growing phase. When the medium pH was controlled at 7.0, the maximun enzyme activities of CGTase and CDase were increased by 12-fold(1300 mU/ml) and 2-fold (225 mU/ml), respectively, compared with the pH-uncontrolled batch culture. The CGTase of the isolate converted soluble starch to CDs with the ratio of α-CD: β-CD: γ-CD=42:46:12 at 55℃. The optimal pH and temperature of CGTase were 6.0 and 60℃, respectively and the optimal pH and temperature of CDase were 6.0 and 55℃. The molecular weights of the purified CGTase and CDase were estimated to be 65,000 and 68,000 dalton, respectively. Among serveral substrates, γ-CD was most rapidly hydrolyzed by the purified CDase.

해마 theta리듬과 pyramidal neuron의 세포내 특성과의 상관관계

권오흥,조진화,남순현,김현정,최병주,김영진,이만기 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.4

Eledctrophysiological phenomena of pyramidal cells in the CAI area of the dorsal hippocampus were recorded from and filled with neurobiotin in anesthetized rats. The electropharmacological properties of membrane as well as the cellular-synaptic generation of rhythmic slow activity (theta)were examined. The intracellular response characteristics of these pyramidal cells were distinctly different from responses of inteneurons. Pyramidal cells had a high resting membrane potential, a low input resistance, and a large amplitude action potential. A afterhyperpolarization was followed a single action potential. Most of pyramidal cells did not display a spontaneous firing. Pyramidal cells displayed weak inward rectification and anodal break excitation. The slope of the frequency-current relation was 53.4 Hz/nA for the first interspike interval and 15.9 Hz/nA for the last intervals, suggesting the presence of spike frequency adaptation. Neurobiotin-filled neurons showed pyramidal morphology. Cells were generally bipolar dendritc processes ramifying in stratum lacunosum-moleculare, radiatum, and oriens. Commissural stimulation discharged pyramidal cells, followed by excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs). The frequency of theat-related membrane potential oscillation was voltage-independent in pyramidal neurons. At strong depolarization levels (less than 30 mV) pyramidal cells emitted sodium spike oscillation, phase-locked to theta. The observations provide direct evidence that theta-related rhythmic hyperpolarization of principal cells is brought by the rhythmically discharging interneurons. Furthermore, the findings in which interneurons were also paced by rhythmic inhibitory postsynaptic potentials during theta suggest that they were periodically hyperpolarized by their GABAergic septal afferents.