• Transactions on Electrical and Electronic Materials
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• 제9권5호
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• pp.209-212
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• 2008

We developed a simple and effective purification method to obtain high-purity single-walled carbon nanotubes (SWCNTs) with low surface damage. The purification process consists of oxidization at $430^{\circ}C$ for 1 h in a furnace system of air atmosphere and homogenization in dilute hydrochloric acid solution for extremely short time. The role of homogenizer was examined during purification process in terms of purity and quality of purified SWCNTs. High-purity and low surface damage of SWCNT products was obtained using homogenizer which was operated at 8500 rpm for 10 min in the environment of 7 % HCI solution. From XRD spectra, we observed that metal catalysts were thoroughly removed. Raman spectra showed that the intensity values of crystallization ($I_{G}/I_{D}$) of purified SWCNTs were very similar with that of pristine SWCNTs. Moreover, the structure damage of purified SWCNTs was hard to find from electron microscopy. Consequently, homogenizing, which is a quick and simple manner, can be promising method for obtaining final SWCNTs with clearly high purity and crystallinity.

• 대한토목학회논문집
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• 제33권3호
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• pp.855-864
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• 2013

지진격리장치로서 천연고무받침의 동적 특성은 주재료인 고무의 동적거동과 비선형 성질에 의존하고 있다. 역학적이나 환경적인 영향으로 인해 고무재료에 노화가 진행되고 결국에는 손상이 불가피하게 발생하게 된다. 고무재료의 노화에 주원인은 높은 온도에서 반응열로 인한 산화반응으로 알려져다. 이에 따라 천연고무받침에 대한 가속 열 노화실험을 수행하여 열 노화 전 후에 대해 받침의 특성값을 상호 비교하였다. 실험 결과 열 노화 현상은 전단강성과 에너지 감쇠 그리고 등가감소계수에 영향이 있음을 알 수 있었다. 또한 열 노화에 의한 동적특성의 저하를 실제 교량에 적용하여 천연고무받침의 열 노화가 교량의 내진성능에 미치는 영향을 수치해석을 통해 비교분석하였다. 그 결과 천연고무받침에 대하여 열 노화에 따른 기본 특성변화가 교량의 내진성능에 미치는 영향은 크지 않음을 알 수 있었다.

• 대한토목학회논문집
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• 제32권2A호
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• pp.109-116
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• 2012

지진격리장치로서 납고무받침의 동적 특성은 주재료인 고무재료의 동적거동과 비선형 성질에 의존하고 있다. 역학적이나 환경적인 영향으로 인해 고무재료에 노화가 진행되고 결국에는 손상이 불가피하게 발생하게 된다. 고무재료의 노화의 주원인은 높은 온도에서 반응열로 인한 산화반응으로 알려져다. 이에 따라 납고무받침의 가속 열 노화실험을 수행하여 열 노화 전 후에 대해 받침의 특성값을 상호 비교하였다. 실험 결과 열 노화 현상은 전단강성과 에너지 감쇠 그리고 등가감소계수에 영향이 있음을 알 수 있었다. 또한 열 노화에 의한 동적특성의 저하를 실제 교량에 적용하여 납고무받침의 열 노화가 교량의 교각의 내진성능에 미치는 영향을 수치해석을 통해 비교분석하였다. 해석결과 납고무받침에 대하여 열 노화에 따른 기본 특성변화가 교량의 내진성능에 미치는 영향은 크지 않음을 알 수 있었다.

• 사상체질의학회지
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• 제23권3호
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• pp.391-401
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• 2011

1. Objectives: Though the eating habits have improved and the living method has become convenient according to the economic growth thanks to the modern industrialization, because of the lack of exercise, obesity, wrong eating habits and stress etc, various symptoms of disease of adults are on the rise. This is the phenomenon that happens as the eating life has become life in the West along with the inundation of the western culture in our society. In this perspective, there has been many various clinical research that's been proceeded so far about the physical constitution and obesity, but there has been little research on the objective analysis of the clinical research about the alimentotherapy using taeeumjoweetang. 2. Methods: In this research we have checked the weights, fat rates, fat weight, abdominal fat rate, blood pressure, and BMI over the objects of the women that were diagnosed as lunisolar system as their physical constitution, and assessed the paramecium lipid, in-blood antioxidation enzyme and the damage of oxidization in the urine by physical constitution-specific of the body shapes that were determined by BMI. The statistical analysis of the current research was processed by using of SPSS 17.0 program. We have figure out statistical amounts such as the arithmetic average, average deviation rate and percentage number. Fro the verification of he significancy of each elements, we have used the paired t-test, ANOVA, Chi-square test at the level of p<0.05. 3. Results and Conclusions: Their characteristics are age $21.20{\pm}1.35$, height $160.30{\pm}6.11cm$, weight $64.66{\pm}8.72kg$, fat rates are $35.97{\pm}4.87%$, fat amount $23.40{\pm}5.48$, abdominal fat rate $0.823{\pm}0.03$, BMI $25.12{\pm}2.79kg/m^2$, and systolic blood pressure $111.60{\pm}10.28mmHg$ and diastolic blood pressure $68.60{\pm}7.43mmHg$ and we have let them take the medicine twice a day for 8 weeks. The clinical result for the Cholesterol, Triglyceride, HDL-cholesterol, LDL-cholesterol, SGOT, SGPT, of the object people was that for the function of the liver, the result of the SGOT and SGPT test was $17.16{\pm}3.05$, $15.00{\pm}2.99IU/L$, which was a decrease, and had statistical meaning, but for the SGOT, though the figure reduced to $11.92{\pm}4.61$, $10.80{\pm}3.07$, it had no statistical meaning. For the whole cholesterol level, the figure reduced to $169.00{\pm}19.95$, $160.08{\pm}22.52$ mg/dL and had statistical significance(p<0.05). Neuter fat number, Triglyceride has slightly increased to $67.52{\pm}36.32$, $68.08{\pm}47.33$ mg/dL but did not have any statistical meaning. The antioxdant enzyme marker standard marker, SOD has increased to $2.52{\pm}0.73$, $2.86{\pm}0.60U/ml$, and had statistical significance(p<0.01). Catalase also increased by $0.63{\pm}0.18$, $1.07{\pm}0.25mmol/ml$ and had statistical meaning(p<0.01). GPx also increased to $204.76{\pm}32.64$ nmol/ml and had statistical meaning(p<0.01). But, for the Total antioxidant, though it has raised to $1.51{\pm}0.26$, $1.57{\pm}0.17nmol/{\mu}l$, it did not have any statistical meaning. MDA of oxidative stress marker has decreased to $1.70{\pm}0.68{\mu}g/ml$, $1.21{\pm}0.50{\mu}g/m$ and had statistical significance(p<0.01). 8-OHdG also decreased $3.35{\pm}0.95ng/ml$, $2.21{\pm}0.50ng/ml$ and had statistical meaning(p<0.01). In this research, we have analyzed the various markers relating to BFM and changes in oxidative enzyme in blood by takingtaeeumjoweetang. Taeeumjoweetang has the positive effect on inbody antioxidant system and reducing the content of cholesterol, which is proven to help losing weight and improving hyperlipidemia statistically. With this research, we hope to improve the lifestyle of those who are either obese or need to manage their dietary habits, and also to become the touchstone of integrating Oriental Medicine with the science of food & nutrition.

• 보존과학회지
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• 제29권2호
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• pp.187-196
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• 2013

본 연구는 해저 환경 내에서의 철제유물 부식인자 중 황화물에 의한 부식상태 및 출수 후 대기 중 고습 상태에서의 손상 현상에 대한 것이다. 이를 위하여 충청남도 태안 마도해역 뻘층에서 출수된 철제유물 4점에서 생성된 부식생성물을 대상으로 황화물의 존재 여부를 확인하고자 SEM-EDS 및 XRD 분석을 실시하였다. 분석 결과, 해저퇴적토 내에서 형성된 부식생성물은 주요 성분이 황(S)이며 화합물로서 황화철(FeS)이 형성되었고, 해저면에 노출된 상태에서 형성된 부식생성물은 일부 결과를 제외하면 표면을 덮고 있는 응결물(concretion)의 영향으로 뚜렷한 부식 양상이 나타나지 않았다. 출수 후 고습 상태에서 철제유물의 손상 현상을 확인하기 위해 부식생성물을 고습 제습환경에 노출시키는 실험을 실시하였다. 실험 결과, 고습 환경에서 황화철 부식생성물의 산화는 황산철($FeSO_4$)과 함께 황산($H_2SO_4$)을 생성하여 철제유물을 2차적으로 부식시킬 수 있음을 확인하였다. 따라서 해저 환경에서 출수된 철제유물의 황화철 부식생성물은 반드시 제거하고 유물의 보존 환경도 제습된 상태가 유지되어야 할 것으로 판단된다.

• 보존과학연구
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• 통권25호
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• pp.119-132
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• 2004

Annals of the Joseon Dynasty is the authentic record of the historical facts and events taken place throughout the entire period of 472 years(25 generations, 1392~1863)described in a chronological order. The tremendous volume of the records contains the factual events taken place in almost all the fields of the Joseon Dynasty ranging from politics, economy to history of the dynasty. Not only because of its affluent contents but also with the precision of its records, it was designated as the National Treasure No. 151 in1973 by the Korean government and also registered as the Memory of the World by UNESCO in October 1997.This study is to report a exhaustive investigation results on the conservation state of annals of the Joseon Dynasty, especially Mt. Jeongjoksan edition, under the storage of the Kyujanggak in order to obtain the current condition, and thereby to estimate the any deterioration of the waxed volumes in the future. According to results of the investigation, we are going to verify damage causes of annals of the Joseon Dynasty, and to consider scientific conservation methods for the permanent preservation of invaluable cultural heritage. The major problem with the preservation of annals has arisen particularly from the deterioration of the waxed volumes of the Mt. Jeongjoksan edition. In order to provide for the counter measures for this problem, we have conducted twice investigations(first :1998~1999, second : 2003) to the internal and external conditions of waxed volumes(Annals of King Taejo~Annals of King Myeongjong).The result of the investigation has indicated that the paper quality of the some of the waxed volumes (Annals of King Taejong~Annals of King Sejong) is cracked and folded and the pages are imbedded to each other due to the hardened or congealed wax on the paper. Some of the pages are even getting moldy. And in order to detect as to whether“ there has been any deterioration progressed to the waxed books in the modern storage facility of the Kyujanggak equipped with constant temperature and humidity condition, the first investigation(1998~1999) and the second investigation(2003) have recorded the values of acidity, whiteness and moisture rate of the waxed paper, reporting an observation that there has been no difference on the measuring items. This indicates that no virtual deterioration has been progressed so far to the waxed volumes preserved in the Kyujanggak. Also, except for the causes of deterioration to the paper by insects and microorganisms, the major cause for the paper damage seems to the change of moisture of the paper caused from the alteration of the temperature and humidity of the storage environment. With this understanding in mind, we have conducted an environmental investigation on the three selected points of the storage in the aspects of the temperature, humidity, air current, $CO_2$,HCHO, and $SO_2$.It has been observed that the temperature stood at $16.9^{\circ}C~20.2^{\circ}C$ and the humidity was stable between 53%~56% during the period of the investigation. The concentration of the carbon monoxide and carbon dioxide of the storage were very similar to those in the air. These data lead to presume that there is no problem in the aspect of carbon oxidization. But the concentration of sulfur dioxide, hydrogen sulfide and formaldehyde of the storage were detected a little higher than those of standard. Therefore, we consider that it is necessary to ventilate the internal air of the store room by means of operating air purification devices.