• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.436-436
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• 2014

본 연구에서는 전 세계적으로 활발히 연구되고 있는 나노바이오센서 분야 중 가장 주목을 받고 있는 LSPR 원리를 이용한 바이오센서를 제작하였다. 금속 나노입자의 국소 표면 플라즈몬 공명현상에 의한 주위환경에 민감하게 반응하는 특성은 고감도 광학형 바이오센서, 화학물질 검출 센서등에 응용된다. 특히 금 나노막대와 같은 1차 나노구조물은 나노막대의 주변 환경 변화에 따라 뚜렷한 플라즈몬 흡수 밴드 변화를 나타냄으로 센서로 적용 했을 때 고감도의 측정이 가능하다. 본 연구에서는 다공성인 알루미늄 양극산화 박막 주형틀을 이용하여 다양한 종횡비를 가지는 금 나노막대를 합성하고, 나노막대 어레이 형태의 박막을 제작하였다. 금 나노막대의 합성은 알루미늄 양극산화막을 사용한 주형제조 방법(template method)을 사용하는 전기화학 증착법을 사용하였다. 우선 부도체인 알루미늄 양극 산화막의 한쪽면을 열증착 장비를 사용하여 금을 증착하여 작업 전극(working electrode)을 형성하였다. 백금 선(platinum wire)을 보조 전극(counter electrode)으로 사용하고 Ag/AgCl 전극을 기준 전극(reference electrode)으로 사용하여 삼전극계(three-electrode system)를 형성하였으며, 금 도금 용액(orotemp 24 gold plating solution, TECHNIC INC.)을 사용하여, 800 mV 전압에서 금 나노 막대를 합성하였다. 금 나노막대의 길이는 테플론 챔버를 통과한 전하량 또는 전기 증착 시간에 비례하여 결정된다. 금 나노막대를 성장시킨 알루미늄 양극산화막을 실리콘 웨이퍼에 은 페이스트를 사용하여 고정시킨 후 수산화나트륨 (NaOH)용액을 사용하여 알루미늄 양극산화막을 녹여내어 수직방향으로 정렬되어 있는 나노 막대 어레이 박막을 제조 하였다. 또한 제작된 금 나노막대 어레이의 광학적 특성을 평가하였다. 본 연구에서와 같이 나노막대를 직경방향으로 측정할 경우, 직경방향의 transverse mode만 측정된다. 금 나노 막대가 알루미늄 양극산화막 안에 포함된 상태로 측정된 금 나노로드 어레이 박막의 광 스펙트럼 분포는 금 나노막대의 가시광영역에서의 흡수 스펙트럼을 측정하였을시 직경 및 길이에 따라 transverse mode의 ${\lambda}$ max (최대 흡광)의 위치가 변화됨을 나타낸다. 실험 결과를 바탕으로 나노막대의 종횡비가 증가함에 따라 흡수 스펙트럼의 transverse mode ${\lambda}$ max가 미약하게 단파장 영역으로 이동하는 것을 확인할 수 있다. 이러한 결과는 원기둥 형태의 금 나노막대의 흡수 스펙트럼에 대한 이론적인 예측과 부합한다. 바이오센서로의 적용 가능성을 확인하기 위하여 자기조립단분자막을 형성하여 항체를 고정하고 CRP에 대한 응답특성을 평가하였다. CRP 항원-항체의 면역반응에 대한 실험 결과 CRP 항원의 농도가 증가함에 따라 넓은 측정범위에서 선형적으로 흡광도가 증가하는 결과를 나타내었으며, CRP 10 fg/ml의 농도까지 검출할 수 있었다. 센서의 선택성을 확인하기 위하여 감지하고자하는 대상물질이 아닌 Tn T 항원을 감지막에 반응시켜 흡광도 변화를 분석하였다. 결과적으로 제작된 센서칩은 선택성을 가지고 측정하고자하는 물질에만 반응함을 확인하였다. 이러한 결과는 다양한 직경을 사용한 부가적인 LSPR현상의 연구에 활용될 수 있을 것이다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.147-156
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• 2016

This study analyzed the impact of changes in the construction business on construction company insolvency according to their size using the vector error correction model. First, this study applied EDF (Expected Default Frequency), which was calculated by KMV (Kealhofer, McQuown and Vasicek) model, as a variable to indicate the insolvency of construction companies. This study set 30 construction companies listed to KOSPI/KOSDAQ for estimating the EDF by size and construction companies were divided into two groups according to their size. To examine the construction business cycles, the amount of construction orders according to the type-residential, non-residential, and civil work- was used as a variable. The serial data was retrieved from TS2000 established by the Korea Listed Companies Association (KLCA), Statistics Korea. The analysis period was between the second quarter of 2001 and fourth quarter of 2015. As a result of calculating the EDF of construction companies by size, as it is generally known, the large-sized construction companies showed lower levels of insolvency than relatively smaller-sized construction companies. On the other hand, impulse response analysis based on VECM confirmed that the level of insolvency of large-scaled companies is more sensitive to business fluctuations than relatively smaller-sized construction companies, particularly changes in the residential construction market. Hence it is a major factor affecting the changes in insolvency of large-sized construction companies.

• Journal of Conservation Science
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• v.25 no.2
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• pp.161-169
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• 2009

The objective of this study was to investigate stability of Korean Paper(Hanji) which is being sold in the Korean markets according to aging treatment. In order to know the aging characteristics, the optical and mechanical properties of before and after wet and dry-heat aging treatment were examined. The optical and mechanical properties were shown higher reduction in the dry-heat aging treatment compared to the wet-heat aging treatment. The Soonji (pure mulberry Hanji) made from black mulberry bast pulp was shown a great reduction of the brightness and whiteness, and increase of the opacity in the aging treatment. On the other hand, in case of mechanical properties, the breaking length of Soonji made from white mulberry bast pulp was significantly higher than that of the others, and the tensile strength was shown drastic reduction in according to Soonji made from black mulberry bast pulp in the aging treatment. The burst strength of Soonji made from black and white mulberry bast pulp was shown the similar value in the wet-heat aging treatment. The folding endurance of Soonji made from white mulberry bast pulp was significantly higher than that of others before and after aging treatment. Consequently, Hanji was affected sensitive in the temperature compared to the humidity. Meanwhile, the density and color of the chinese ink was no significant changes before and after wet and dry-heat aging treatment.

• Journal of Life Science
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• v.17 no.4 s.84
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• pp.535-539
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• 2007

The fructus of Crataegus pinnatifida Bunge has been used as medicinal and food source in worldwide. In this study, a strong direct thrombin inhibition and antithrombosis activity were identified from the methanol extract of C. pinnatifida Bunge fructus. The solvent fractionation of fructus extract using hexane, ethylacetate, butanol revealed that the butanol fraction has a prominent antithrombin activity. Thrombin time(blood-clot formation time) and activated partial thromboplastin time(aPTT) extended to 835% and 315% by addition of the butanol fraction at concentration of 1.25 mg/mL, whereas thrombin time extended to 287% by addition of aspirin at concentration of 1,25 mg/mL. The butanol fraction showed anthrone-positive and weak ninhydrine-postive reaction. The thrombin inhibitory activity was not related to previously reported flavonoids or polyphenols. The activity was maintained against acid treatment(0.5 N HCl for 120 min), but rapidly lost by heat-treatment($100^{\circ}C$ for 30 min). Our results suggested that fructus of C. pinnatifida Bunge with non-heat treatment process could be developed as a natural source of antithrombosis.

• Parasites, Hosts and Diseases
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• v.26 no.4
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• pp.239-244
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• 1988

In order to observe the antigenic fractions in saline extract of adult Paragonimus westermani, proteins in the crude extract were separated by sodium dodecyl sulfate-polyacylamide gel electrophoresis(SDS.PAGE) in reducing conditions. The separated protein fractions were transferred to nitrocellulose paper on which 20 sera from human paragonimiasis were reacted and immunoblottrd. Out of 15 stained protein bands in SDS-PAGE, 7 reacted with infected sera while 8 did not. Additionally, 7 unstained protein bands in SDS-PAGE reacted with the sera. Of 14 reacted bands, 30 kilodalton(kDa) band was the most frequently reacted (95%) and was a strong antigen. Protein bands of 23 and 46 kDa were also strong antigens. Bands of over 150 kDa, 120 kDa, 92 kDa, 86 kDa, 74 kDa, 62 kDa, 51 kDa, 32 kDa, 28 kDa, 16.5 kDa and 15.5 kDa were also reactive but their frequencies of the reaction were variable. Key words: Paragonimus westermani, human paragonimiasis, antigenic proteins, SDS-PAGE/ immunoblot

• Environmental and Resource Economics Review
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• v.16 no.3
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• pp.485-510
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• 2007

The purpose of this paper is to empirically analyze the economic effect of energy saving investment on the improvement of energy intensity. The data used in this paper are panel data, both time-series and cross-section data. In addition, eight manufacturing sectors has been divided into two groups: massive energy consuming (four industries) and non-massive energy consuming (four industries) ones and the time period of analysis is from 1982 to 2004. According to the empirical results, firstly, energy saving investment has a negative relationship with energy intensity, however, its effect is not high in terms of absolute volume of energy consuming. Secondly, in improving energy intensity of energy saving investment, its elasticity IS higher in non-massive energy consuming sector compared it with massive energy consuming sector. Thirdly, automation investment is also playing an important role in energy conservation. The elasticities of automation investment to energy intensity are larger than those of energy saving investment. In terms of the reduction of greenhouse gas per investment unit cost, however, energy saving investment has larger effect than automation investment.

• Journal of Conservation Science
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• v.29 no.1
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• pp.55-67
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• 2013

This study focused on analysis condition and application method of the passive infrared thermography according to the direction and time to nondestructively detect the blistering zone of stone cultural heritage. As a result, the passive thermographic images showed different temperature characteristics by time because it sensitively reacts to air temperature, insolation and sunshine direction. In particular, the insolation and sunshine direction, which are periodically changed from 6:00 to 17:00, irregularly made surface temperature. In addition, surface temperature differences were brought on fresh zones and blistering zones except specific time since blistering causes erratic thermal transfer. As a result of examining the detection characteristics of blistering by time, the blistering was well detected between 9:00 and 10:00 when there was rapid increase in air temperature and insolation in all direction except the north. However, this study isn't considered effects of four seasons because it is carried out in autumn, and the passive thermography has difficulty to analyze the quantitative area of blistering zone. Therefore, an additional study for synthetic consideration of the passive thermography analysis about four seasons and quantitative modeling of blistering zone using the active thermography are needed.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.475-482
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• 2007

The thermal and optical properties of glucose penta(cholesteryloxycarbonyl)alkanoates (CAGLn, n = 2~8, 10, the number of methylene units in the spacer) were investigated. All the CAGLn formed monotropic cholesteric phases with left-handed helical structures. CAGLn with n = 2 or 10, in contrast with CAGLn with $3{\leq}n{\leq}8$, did not display reflection colors over the full cholesteric range, suggesting that the helical twisting power of the cholesteryl group highly depends on the length of the spacer joining the cholesteryl group to the glucose chain. The isotropic-cholesteric transition point ($T_{ic}$) decreased with increasing n and showed no odd-even effect. The plot of transition entropy at $T_{ic}$ against n had a sharp negative inflection at n = 7. The optical pitches (${{\lambda}_m}^{\prime}$ s) of CAGLn with $3{\leq}n{\leq}8$ decreased with increasing temperature. However, the temperature dependence of the ${\lambda}_m$ of the derivatives exhibited pronounced dependence on n. The transitional properties and the temperature dependence of the ${\lambda}_m$ observed for CAGLn were discussed in terms of the differences in arrangement of the cholesteryl groups and the conformation of the molecules.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.564-569
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• 2000

An enzyme-linked immunosorbent assay(ELISA) was developed for the detection of milk proteins in processed foods. The ${\alpha}_{s1}-casein({\alpha}_{s1}-CN)$, a heat stable major milk protein, was immunized into rabbits to produce specific antibodies. When competitive indirect ELISA(ciELISA) using $anti-{\alpha}_{s1}-CN$ antibodies was established, its detection limit was $0.1\;{\mu}g/mL$. The reactivities of the specific antibodies toward ${\alpha}_{s1}-CN$, skim milk, ${\beta}-CN$ and whey protein isolate(WPI) were 100, 37, 0.14 and 0.04%, respectively, as determined by ciELISA. However $anti-{\alpha}_{s1}-CN$ antibodies did not have any reactivity to other milk proteins such as ${\beta}-lactoglobulin,\;{\alpha}-lactalbumin$, bovine serum albumin, and isolated soy protein. When sandwich ELISA was established, its detection limit was $0.01\;{\mu}g/mL$ which was 10 times more sensitive than that of ciELISA. In the spike test which was performed by adding 1-10% of whole CN to market milk, mean assay recovery as determined by sandwich ELISA was 94.8%(CV, 8.2%). Food stuffs and dairy products were assayed by sandwich ELISA to show 29, 0.13, 0.25, and 6.9% of whole CN in skim milk powder, WPI, semi-solid yoghurt, and processed cheese, respectively.

• Polymer(Korea)
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• v.33 no.3
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• pp.254-262
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• 2009

Nine kinds of hydroxypropyl celluloses (HPCs) with degree of substitution (DS) and molar substitution (MS) ranging from 2.10 to 2.71 and 2.3 to 6.7, respectively and seven kinds of fully butanoated HPCs (BPCs) based on the HPCs with $2.3\;{\le}\;MS\;{\le}\;6.7$ were synthesized, and the molecular characteristics of HPCs and the thermotropic liquid crystalline properties of the derivatives were investigated. MS was nearly equal to DS for small value of DS, but it became exceedly larger than DS for $DS{\gtrsim}1$, showing that in the later stages of reaction, propylene oxide preferentially adds to the side chains rather than the main chain. All the derivatives formed enantiotropic cholesteric phases with right-handed helical structures. The glass and clearing transition temperatures of both HPCs and BPCs were decreased with increasing MS. The optical pitches (${\lambda}_m'S$) of BPCs, as well as HPCs themselves, increased with increasing temperature. However, the ${\lambda}_m'S$ of both HPCs and BPCs at the same temperature increased with increasing MS. Moreover, the temperature dependence of ${\lambda}_m$ of HPCs was weaker than that of BPCs, suggesting that the helical twisting power of the cellulose chain highly depends on the length and chemical structure of the side chain introduced in cellulose chain.