• 한국가금학회지
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• 제14권2호
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• pp.89-96
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• 1987

본 연구에서는 가금에 있어 세포유전학적 방법을 이용하여 닭 염색체의 분리방법과 G, C-banding에 의한 분염분석 방법을 재고하여 보다 명확한 염색체의 형태적 양상을 제시하였다. 염색체의 분리는 성장중인 초기배아를 이용하므로써 유사분열 중기상을 쉽게 포악할 수 있었으며, 성장 4-5일째의 배아조직으로부터 염색체의 분리는 다소 불편함이 많았다. 가금에 있어 염색체 분리기술중 가장 중요한 것으로 적합한 sample의 채취와 적절한 중기상의 유도, hypotonic 처리에 따른 뚜렷한 형태의 유도, 도말방법 및 염색의 처리과정이다. 또한 보다 명확한 염색체의 분석을 위하여서는 중기 분열상중 초기 중기 상태의 상을 포착함이 바람직하다. G. C-banding 처리를 위해서는 공히 충분하고도 완전히 건조된 air-dried prepration된 sample을 이용하여야 바람직한 결과를 얻을 수 있으며, slide의 보존시간에 따라 band 양상에 많은 차이를 나타낸다. G-banding 양상에 크게 영향하는 요인으로서는 trypsin의 농도, 처리시간, 처리온도가 주된 작용을 하고, Giemsa solution에 사용하는 buffer의 pH도 크게 작용하는 것으로 나타났다. C-banding에 있어서는 Ba(OJ)$_2$의 농도 처리시간, 처리온도가 큰 영향을 미친 바 다소 짧은 시간의 처리가 바람직한 양상을 보이고, 처리전 HCl 처리로서 세포들의 균일성을 가하고, 처리후 철저한 수세가 좋은 결과를 나타내었다. Band 양상의 보다 정확한 해석을 위해서는 densitometer를 이용하므로써 구체적 양상을 분석할 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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• pp.139-141
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• 2005

It is possble to study charge transfer property which is caused by height variation because we can see the organic materials barrier height and STM tip by organic materials energy band gap. Here, we investigated the negative differential resistance(NDR) and charge transfer property of self-assembled 4,4-Di(ethynylphenyl)-2'-nitro-1-(thioacetyl)benzene, which has been well known as a conducting molecule. Self-assembly monolayers(SAMs) were prepared on Au(111), which had been thermally deposited onto pre-treatment($H_{2}SO_{4}:H_{2}O_{2}$=3:1) Si. The Au substrate was exposed to a 1 mM/l solution of 1-dodecanethiol in ethanol for 24 hours to form a monolayer. After thorough rinsing the sample, it was exposed to a $0.1{\mu}M/1$ solution of 4,4-Di(ethynylphenyl)-2'-nitro-1-(thioacetyl)benzene in dimethylformamide(DMF) for 30 min and kept in the dark during immersion to avoid photo-oxidation. After the assembly, the samples were removed from the solutions, rinsed thoroughly with methanol, acetone, and $CH_{2}Cl_{2}$, and finally blown dry with $N_2$. Under these conditions, we measured electrical properties of self-assembly monolayers(SAMs) using ultra high vacuum scanning tunneling microscopy(UHV-STM). The applied voltages were from -1.50 V to -1.20 V with 298 K temperature. The vacuum condition is $6{\times}10^{-8}$ Torr. As a result, we found that NDR and charge transfer property by a little change of height when the voltage is applied between STM tip and electrode.

• Composites Research
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• 제27권3호
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• pp.109-114
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• 2014

나노입자에 대한 복합재료 수요가 증가되면서 효과적인 나노입자 보강재를 이용한 나노복합재료 제조공정 단순화를 추구하고 있다. 본 연구에서는 나노입자를 활용하여 전도성과 계면 강도를 향상시킨 나노입자 강화유리섬유 소재에 대한 연구를 진행하였다. 탄소계 나노입자의 형상에 따른 유리섬유 표면에 흡착된 나노입자 상태를 FE-SEM으로 분석하였다. 나노입자 코팅층의 내구성을 평가하기 위한 방법으로 초음파 세척과정에 따른 나노입자의 세척 정도를 분석하여 탄소계 나노입자의 형상에 따른 나노입자 코팅층의 내구성을 분석하였다. 동적피로 실험을 통하여 나노입자 강화 유리섬유/에폭시의 계면강도를 나노입자 형상에 따른 차이에 따라 비교하였다. 나노입자 코팅층의 내구성은 단섬유 강화 복합재료시편을 이용하여 분석하였다. 겉보기 강성도 결과와 나노입자코팅층의 전도성 변화를 분석하여 코팅층의 다기능성을 분석할 수 있었다. 판상형의 나노입자 보다는 섬유 형태의 나노입자가 유리섬유 표면에 흡착성이 용이하였다. 계면 내구성 및 안정성에 효과가 있음을 확인하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.126-126
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• 2014

Label-free biomolecular assay based localized surface plasmon resonance (LSPR) of noble metal nanoparticles enables simple and rapid detection with the use of simple equipment. Nanosized metal nanoparticles exhibit a strong absorption band when the incident light frequency is resonant with the collective oscillation of the electrons, which is known as the LSPR. Here we demonstrate localized surface plasmon resonance (LSPR) substrates such as plasmonic Au nanodisks fabricated by a nanoimprinting process and gold nanorod-immobilized surfaces and their applications to highly sensitive and/or label-free biosensing. To increase detection sensitivity various bioreceptors weree designed. A single chain variable fragment (scFv) was used as a receptor to bind C-reactive protein (CRP). The results of this effort showed that CRP in human serum could be quantitatively detected lower than 1 ng/ml. Aptamers, which were immobilized on gold nanorods, were used to detect mycotoxins. The specific binding of ochratoxin A (OTA) to the aptamer was monitored by the longitudinal wavelength shift of LSPR peak in the UV-Vis spectra resulting from the changes of local refractive index near the GNR surface induced by accumulation of OTA and G-quadruplex structure formation of the aptamer. According to our results, OTA could be quantitatively detected lower than 1 nM level. Additionally, aptamer-functionalized GNR substrate was quite robust and can be regenerated many times by rinsing at 70 OC to remove bound target. During seven times of washing steps, the developed OTA sensing system could be reusable. Moreover, the proposed biosensor exhibited selectivity over other mycotoxins with an excellent recovery for detection in grinded corn samples, suggesting that the proposed LSPR based aptasensor plays an important role in label-free detection of mycotoxins.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2010년도 춘계학술발표대회
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• pp.35.1-35.1
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• 2010

The Cu(In,Ga)Se2(CIGS) thin film solar cells have been achieved until almost 20% efficiency by NREL. These solar cells include chemically deposited CdS as buffer layer between CIGS absorber layer and ZnO window layer. Although CIGS solar cells with CdS buffer layer show excellent performance, many groups made hard efforts to overcome its disadvantages in terms of high absorption of short wavelength, Cd hazardous element. Among Cd-free candidate materials, the CIGS thin film solar cells with Zn compound buffer layer seem to be promising with 15.2%(module by showa shell K.K.), 18.6%(small area by NREL). However, few groups were successful to report high-efficiency CIGS solar cells with Zn compound buffer layer, compared to be known how to fabricate these solar cells. Each group's chemical bah deposition (CBD) condition is seriously different. It may mean that it is not fully understood to grow high quality Zn compound thin film on the CIGS using CBD. In this study, we focused to clarify growth mechanism of chemically deposited Zn compound thin film on the CIGS, especially. Additionally, we tried to characterize junction properties with unfavorable issues, that is, slow growth rate, imperfect film coverage and minimize these issues. Early works reported that film deposition rate increased with reagent concentration and film covered whole rough CIGS surface. But they did not mention well how film growth of zinc compound evolves homogeneously or heterogeneously and what kinds of defects exist within film that can cause low solar performance. We observed sufficient correlation between growth quality and concentration of NH3 as complex agent. When NH3 concentration increased, thickness of zinc compound increased with dominant heterogeneous growth for high quality film. But the large amounts of NH3 in the solution made many particles of zinc hydroxide due to hydroxide ions. The zinc hydroxides bonded weakly to the CIGS surface have been removed at rinsing after CBD.

• 한국진공학회지
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• 제16권5호
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• pp.366-370
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• 2007

밀도가 높고 주기적으로 배열된 나노 크기의 기공이 25nm 두께의 실리콘 산화막 기판위에 형성 되었다. 나노미터 크기의 패턴을 형성시키기 위해서 자기조립물질을 사용했으며 폴리스티렌(PS) 바탕에 벌집형태로 평행하게 배열된 실린더 모양의 폴리메틸메타아크릴레이트(PMMA)의 구조를 형성하였다. 폴리메틸메타아크릴레이트를 아세트산으로 제거하여 폴리스티렌만 남아있는 나노크기의 마스크를 만들었다. 폴리스티렌으로 이루어진 나노패턴의 지름은 $8{\sim}30nm$ 였고 높이는 40nm였으며, 패턴과 패턴사이의 간격은 60nm였다. 형성된 패턴을 실리콘 산화막 위에 전사시키기 위해 불소 기반의 화학 반응성 식각을 사용하였다. 실리콘 산화막에 형성된 기공의 지름은 $9{\sim}33nm$였다. 실리콘 산화막을 불산으로 제거하여 실리콘에 형성된 기공을 관찰하였고, 실리콘기판에 형성된 기공의 지름은 $6{\sim}22nm$였다. 형성된 기공의 크기는 폴리메틸메타아크릴레이트의 분자량과 관계가 있음을 알 수 있었다.

• 한국축산식품학회지
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• 제32권6호
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• pp.763-768
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• 2012

This study has been performed to measure the prevalence and microbial flora on chicken slaughtering as well as the processing process from the months of October to November. Whole-chicken rinsing technique was used in order to analyze the incidence of microorganisms on chicken carcass at the stage before chilling (after evisceration), after chilling and after cutting. The swab technique was used on processing the processed samples, such as working plates and cutting knives. Brine and cooling water from four cooling tubs were taken from each processing processes and were used as samples. Furthermore, the matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) for whole cell fingerprinting in combination with a dedicated bioinformatic software tool was used to identify the isolated microorganisms. Of the tested samples and processes, brine ($4.50{\pm}0.64$ Log CFU/mL) and chicken carcass before chilling ($4.15{\pm}0.46$ Log CFU/mL) showed the highest population of microorganisms; the predominant microbial flora of them were Moellerella wisconsensis (54.84%), a member of the Enterobacteriaceae family, and Escherichia coli (60.36%), respectively. However, the predominant microbial flora of cut carcass was changed to Staphylococcus aureus (27.32%), which is a kind of pathogenic microorganism that can cause a food-borne illness. Therefore, the slaughtering and processing procedure of chicken are needed to be controlled more hygienically.

• 한국치위생학회지
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• 제14권2호
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• pp.163-171
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• 2014

Objectives : This study aims to improve health and the quality of life of teenagers by identifying an association between the periodontal status and oral health behaviors of Korean teenagers using 2010 Korean National Oral Health Survey data. Methods : Subjects were teenagers aged from 12 to 15 in Korean National Oral Health Survey (KNOHS). The questionnaire consisted of periodontal status, general characteristics, periodontal related factors, and oral health related behaviors. Results : Gingival bleeding was found in 56.9% of teenagers because unhealthy periodontal status and tartars were found. Those who were 15 years old had unhealthier periodontal status than those who aged 12 years old. Those who lived in rural areas tended to have worse periodontal status than those who lived in the big cities. Access to dental floss, mouth rinsing solution and regular dental checkup tended to make the healthier periodontal status. Smokers had the worse periodontal status than the nonsmokers. Conclusions : The oral health care in the teenagers aged from 12 to 15 is very important because the permanent dentition is completed in this stage. It is necessary to lay emphasis on the oral health improvement and dental caries prevention program to the teenagers.

• Restorative Dentistry and Endodontics
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• 제34권1호
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• pp.38-41
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• 2009

복합레진 수복을 위해 상아질에 total-etch adhesive system을 적용할 경우, 37% 인산 산부식제가 널리 사용되고 있다. 37% 인산은 매우 강력한 부식제로 구강점막이나 안면피부와 접촉되었을 때 심각한 해로운 효과가 발생될 수 있다. 이 증례 보고에서는 복합레진 수복과정에서 사용된 인산 산부식제에 의해 안면피부에 발생된 의원성 화학적 화상을 보고하고자 한다. 산부식제에 의한 화학적 화상은 산부식제를 부주의하고 부적절하게 사용함으로 발생될 수 있으며, 이러한 의원성 손상을 방지하기 위해서는 산부식과 수세과정 후 산부식제가 완전히 제거되었는지를 확인하여야하며, 복합레진 수복 시 러버댐이나 적절한 격리 기구를 사용하는 것이 필요할 것이다. 화상이 발생하였다면, 적절한 응급처치 후 피부과로 의뢰하는 것이 필요할 것이다.

• 한국의류학회지
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• 제5권1호
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• pp.9-14
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• 1981

The influence of laundering conditions on calcium deposition on the fabric was studied by repeated laundering the cotton fabric with soap in the hard water of 200 P.P.M. $CaCO_3$. The experimental variables were: 1) soap concentrations ($0.06\%$, $0.13\%$, $0.25\%$), 2) water contents in the fabric after hydroextraction. ($65\%$, $150\%$, $315\%$), 3) builders (Na-EDTA, sodium carbonate, sodium metasilicate), 4) washing cycle (5, 10, 15, 20 cycles). The fabric was washed for 15 minutes at $23\pm1^{\circ}C$ in a washing machine (Model; Gold Star Wp-2005) under the similar conditions with those of home laundering, and rinsed 5 times for 5 minutes. The amount of calcium deposits on the fabric was determined by the EDTA-Back titration method described by Wasserman and Basch. Results of this study were follows: 1) The amount of calcium deposits on the fabric increased with increasing wash cycles. 2) During the rinsing process, residual calcium content on the fabric increased with water content in the fabric after hydroextraction. 3) The amount of calcium deposits on the fabric decreased with the increasing soap concentration above the equivalent amount of calcium ion content in the water. 4) Sequestering agents and alkaline builders influenced the amount of calcium deposits on the fabric. The amount of calcium deposits on the fabric was in the order of sodium metasilicate, sodium carbonate, nonbuilder, and EDTA.