• 한국식품저장유통학회지
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• 제23권2호
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• pp.162-165
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• 2016

본 연구는 에테폰과 부형제를 혼합하여 에틸렌 발생 타블렛을 제조하였고, 에틸렌 가스 활성조건을 구명한 결과는 다음과 같다. 온도조건별 타블렛의 에틸렌 발생량은 온도가 높을수록 많은 발생을 보였다. Activator pH 조건별 에틸렌 발생량은 pH 7.0 및 9.0 조건에서는 발생량이 약 2 ppm으로 미미하였으나, pH 13.0에서 타블렛의 에틸렌 발생량은 Prosolv 부형제 94.05 ppm, HPMC 부형제 126.28 ppm, Crosscamellose 부형제 100.11 ppm으로 각각 나타났다. 제조된 타블렛의 마손도는 Prosolv 부형제 0.1%, HPMC 부형제 0.3%, Crosscamellose 부형제 54.1%로 나타나 Crosscamellose 타블렛은 부적합하다고 판단되었다. 붕해도의 경우 각각의 부형제에 따라 큰 차이를 보였으며, Prosolv 부형제 1분, HPMC 부형제 7분 이상, Crosscamellose 부형제 5분으로 각각 나타났다. 최종 선정된 부형제인 Prosolv 타블렛의 시간대별 에틸렌 발생 측정결과 가스포집 20시간 까지 에틸렌 발생량은 꾸준히 증가하였지만 20시 이후의 발생은 미미하였고 지속적인 가스 발생은 처리 후 20시간으로 나타났다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2017년도 춘계공동학술대회
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• pp.111-111
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• 2017

There still exist adhesives that have toxic compounds or consist of those materials in both our life and lots of industries. For instance, formaldehyde adhesive had been still used for woodworking and some medical adhesives had been considered as toxicity problems. In this situation, natural adhesives from raw materials have been suggested as an one of considerable interests. Natural adhesives in recent have been reported fabrication methods via biological materials such as proteins, celluloses, and starches. By-products derived from agricultural something have them richly and each has additional special properties. Using these properties to make natural adhesives, unique adhesives would be attained. In particular, rice-based adhesive is such a good example. Rice-based by-product adhesives have interestingly some pros pertaining to high adhesive strength, excellent water resistance and could dramatically be reduced a formaldehyde a harmful component of plywood. Hence, rice-based adhesive like glues could be applied to lots of industries including agricultural and biological technology. This review paper highlighted some recent development on natural adhesives as a promising biomaterial for agricultural and biological technology fields. The design of agricultural by-product-based natural adhesives were described to demonstrate the application of agricultural and biological technology

• Journal of Pharmaceutical Investigation
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• 제36권4호
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• pp.263-269
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• 2006

Deficiencies in the early ADMET(absorption, distribution, metabolism, elimination and toxicity) information on drug candidate extract a significant economic penalty on pharmaceutical firms. Microscale cell culture analogue-microscale gastrointestinal(${\mu}CCA-{\mu}GI$) device using Caco 2, L2 and HEp G2/C3A cells, which mimic metabolic process after absorption occurring in humans was used to investigate the toxicity of the model chemical, acetaminophen(AAP). The toxicity of acetaminophen determined after induction of CYP 1A1/2 in Caco 2 cells was not significant. In a coculture system, although no significant reduction in viability of HEp G2/C3A and L2 cells was found, approximately 5 fold increase in the CYP 1A1/2 activity was observed. These results appear to be related to organ-organ interaction. The oral administration of a drug requires addition of the absorption process through small intestine to the current ${\mu}CCA$ device. Therefore, a perfusion coculture system was employed for the evaluation of the absolution across the small intestine and resulting toxicity in the liver and lung. This system give comprehensive and physiologic information on oral uptake and resulting toxicity as in the body. The current ${\mu}CCA$ device can be used to demonstrate the toxic effect due to organ to organ interaction after oral administration,

• Elastomers and Composites
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• 제44권3호
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• pp.244-251
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• 2009

최근 들어, 자연의 기능성 표면을 모사하여 공학적으로 이용하려는 연구가 전세계적으로 급격히 증가하고 있다. 자연계에 존재하는 표면의 여러 기능을 우리 생활에 응용할 수 있다면, 현재 인류가 직면하고 있는 환경오염, 에너지고갈, 물/식량 부족 등의 문제들을 해결하는데 큰 도움이 될 뿐만 아니라, 우리가 일상생활에 사용하는 많은 제품들의 표면 기능을 고도화시킬 수 있기 때문이다. 이 글에서는 다양한 기능을 가진 자연의 표면 중 마이크로/나노구조물을 이용하여 초발수 특성을 갖는 표면에 대하여 살펴보고 초발수 표면의 이론적인 배경 및 초발수 표면을 구현하기 위한 여러 연구들에 대하여 소개하고자 한다.

• BioChip Journal
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• 제12권4호
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• pp.326-331
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• 2018

Contamination by pesticides is an everincreasing problem associated with fields of environmental management and healthcare. Accordingly, appropriate treatments are in demand. Pesticide detection methods have been researched extensively, aimed at making the detection convenient, fast, cost-effective, and easy to use. Among the various detecting strategies, paper-based assay is potent for real-time pesticide sensing due to its unique advantages including disposability, light weight, and low cost. In this study, a paper-based sensor for chlorpyrifos, an organophosphate pesticide, has been developed by layering three sheets of patterned plates. In colorimetric quantification of pesticides, the blue color produced by the interaction between acetylcholinesterase and indoxyl acetate is inhibited by the pesticide molecules present in the sample solutions. With the optimized paper-based sensor, the pesticide is sensitively detected (limit of detection =8.60 ppm) within 5min. Furthermore, the shelf life of the device is enhanced to 14 days after from the fabrication, by treating trehalose solution onto the deposited reagents. We expect the paper-based device to be utilized as a first-screening analytic device for water quality monitoring and food analysis.

• 디지털융복합연구
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• 제14권5호
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• pp.459-471
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• 2016

이 연구에서는 백삼(WG), 홍삼(RG) 흑삼(BG) 추출물의 효능차이를 비교하고자 항산화 및 항염 활성을 측정하였다. 세포독성 측정 결과 WG, RG, BG 모두 95% 이상의 세포 생존율을 나타내었고, 페놀함량, DPPH, ABTS 라디컬 소거능, ROS 생성량을 조사한 결과 WG와 RG에 비해 BG가 높은 항산화 활성을 보였다. NO생성 저해활성은 RG가, $PGE_2$생성 저해활성은 WG가 높았다. 염증성 사이토카인 생성량 감소에 미치는 영향을 측정한 결과, IL-$1{\beta}$ 생성량의 경우, WG와 RG가, IL-6 생성량의 경우 BG가 가장 큰 것으로 확인하였다. TNF-${\alpha}$ 생성량은 WG, RG, BG 모두 대조군과 비교하여 차이가 없었다. 이상의 분석 자료가 건강기능 식품과 기능성 화장품 원료 개발 등 전 임상단계의 기초적 자료로 가치가 있을 것으로 판단된다.

• 한국재료학회지
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• 제28권4호
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• pp.201-207
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• 2018

Infrared(IR) heating has many advantages, such as energy efficiency, reduced heating time, cleanliness, equipment compactness, high drying rate and easy automation. These features of IR heating provide widely industrial applications, such as surface heat treatment in semiconductor fabrication, thermoforming of polymers, drying and disinfection of food products, heating to metal forging, and drying of wet materials. In this study, the characteristics of a protected gold mirror were examined by spectrophotometer and the lifetime of the coating layers were evaluated by a cross-cutting method and salt spray test. The effects of manufacturing conditions on the protected gold mirror were seen and remedies for these effects were noted in order to improve the properties of the protected gold mirror in the drying process. The reflectance and lifetime of the protected gold mirror was influenced by manufacturing conditions, such as surface roughness and forming conditions of the anti-oxide layer, the adhesion layer, the reflecting layer and the protection layer. The results of this study showed that the protected gold mirror manufactured using a buffing method for pre-treatment resulted in the most effective reflectance. In addition, $Al_2O_3$ coating on an Al substrate as an anti-oxide layer was more effective than the anodizing process in the test of reflectance. Furthermore, the protected gold mirror manufactured by layers forming of various materials resulted in the most effective reflectance and lifetime when coated with $Al_2O_3$ as the anti-oxide layer, coated Cr as the adhesion layer, and coated $MgF_2$ as the protection layer.

• 대한치과의사협회지
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• 제53권11호
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• pp.789-794
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• 2015

섭식 연하장애는 수술이나 치료로 인한 기질적 원인, 뇌혈관장애나 뇌성마비, 근육이나 신경장애 등으로 인한 기능적 원인, 그리고 거식증이나 폭식증과 같은 심리적 원인에 의해 발생할 수 있다. 치과의원급에서는 주로 음식물의 인식장애 단계부터 인두로의 전달장애 단계까지의 환자에게 적극적으로 도움을 줄 수 있으며, 그 방법으로는 치의학적 전문지식을 바탕으로 환자의 섭식, 저작과정을 주의 깊게 관찰하여 문제점을 파악하여 각 단계에 적절한 기초 훈련과 섭식 훈련을 실시하는 것이며, 또한 필요시 혀 접촉 보조장치와 같은 장치를 제작하여 환자에게 장착시키고 섭식, 연하 훈련을 시행하여 환자의 연하능력을 개선시켜줄 수 있다. 하지만 무엇보다 가장 중요한 것은 환자가 식전과 식후에 엄격한 구강관리를 시행할 수 있도록 잘 지도하고, 치과의 정기적 방문과 전문적 관리를 통해 구강내 저작기관의 해부학적, 기능적 문제점을 해결해 주도록 하며, 이 때 마다 심리적으로도 환자가 섭식, 연하에 문제가 없도록 세심하게 설명하고 상담해 주는 것으로, 이는 모두 치과의사의 책무라고 할 수 있다.

• 한국환경과학회지
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• 제25권12호
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• pp.1613-1622
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• 2016

Zeolite (FZ), prepared from fly ash, was immobilized with polyacrylonitrile (PAN) to fabricate PAN/FZ beads. The prepared PAN/FZ beads were characterized by scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The optimum ratio to prepare PAN/FZ beads was 0.3 g of PAN to 0.3 g of FZ. The diameter of the prepared PAN/FZ beads was about 3 mm. Sr and Cu ion adsorption experiments were conducted with PAN/FZ beads. A pseudo-second-order model fit the kinetic data for Sr and Cu ion adsorption by PAN/FZ beads well. The equilibrium data fitted well with the Langmuir isotherm model, and the maximum adsorption capacities were 96.5 mg/g and 74.6 mg/g for the Sr and Cu ions, respectively. Additionally, the values of thermodynamic parameters such as Gibbs free energy (${\Delta}G^o$), enthalpy (${\Delta}H^o$) and entropy (${\Delta}S^o$) were determined. The positive values of ${\Delta}H^o$ revealed the endothermic nature of the adsorption process and the negative values of ${\Delta}G^o$ were indicative of the spontaneity of the adsorption process.

• 한국분말재료학회지
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• 제17권6호
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• pp.443-448
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• 2010

The $\beta$ phase Ti-Nb-Sn-HA bio materials were successfully fabricated by high energy mechanical milling and pulse current activated sintering (PCAS). Ti-6Al-4V ELI alloy has been widely used as biomaterial. But the Al has been inducing Alzheimer disease and V is classified as toxic element. In this study, ultra fine sized Ti-Nb-Sn-HA powder was produced by high energy mechanical milling machine. The $\beta$ phase Ti-Nb-Sn-HA powders were obtained after 12hr milling from $\alpha$ phase. And ultra fine grain sized Ti-Nb-Sn-HA composites could be fabricated using PCAS without grain growth. After sintering, the microstructures and phase-transformation of Ti-Nb-Sn-HA biomaterials were analyzed by scanning electron microscope (SEM) and X-ray diffraction (XRD). The relative density was obtained by Archimedes principle and the hardness was measured by Vickers hardness tester. The $\beta$-Ti phase was obtained after 12h milling. As result of hardness and relative density, 12h milled Ti-Nb-Sn-HA composite has the highest values.