• Title/Summary/Keyword: 나노과학

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The Ameliorating Effect of Kyung-Ok-Go on Menopausal Syndrome Observed in Ovariectomized Animal Model (난소 절제 동물모델을 이용한 경옥고의 갱년기 증후군 개선 효과)

  • Cho, Kyungnam;Jung, Seo Yun;Bae, Ho Jung;Ryu, Jong Hoon
    • Korean Journal of Pharmacognosy
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    • v.51 no.4
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    • pp.310-316
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    • 2020
  • Kyung-Ok-Go (KOK) is a traditional prescription used for debilitating natural aging and post-illness debilitation. KOK has been used in a variety of ways because it strengthens immunity, prevents illness, and helps recovery in case of illness. In particular, recent research has revealed that KOK helps improve memory and cognition. Therefore, in this study, we investigated whether KOK was effective in improving memory decline and depression-state observed during menopause. In the present study, we employed ovariectomized mouse as an animal model for measuring menopausal syndrome. The administration of KOK for 8 weeks, the object recognition memory and working memory were improved in novel object recognition test and Y-maze test. And in the forced swimming test, the immobility time were decreased. Additionally, the expression level of mature brain derived neurotropic factor (mBDNF) was increased by KOK administration in ovariectomized mouse hippocampus. These results suggested that KOK could improve cognitive decline and depression during menopausal period, and it might be come from enhancing expression level of mBDNF in hippocampus.

분자동역학을 이용한 전이금속 나노구조체의 특성연구

  • Yun, Gi-Hun;Jo, Min-U
    • Proceeding of EDISON Challenge
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    • 2014.03a
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    • pp.359-370
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    • 2014
  • 두 가지 서로 다른 원소를 포함한 나노 크기의 금속클러스터가 여러 화학반응의 효과적인 촉매로 각광받고 있다. 그래서 본 연구에서는 분자동역학을 이용하여 48개로 구성된 Au-Pd 나노 금속 클러스터의 다양한 구조와 상전이 현상을 살펴보고자 한다.

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Smart Structural Health Monitoring Using Carbon Nanotube Polymer Composites (탄소나노튜브 고분자 복합체 기반 스마트 구조건전성 진단)

  • Park, Young-Bin;Pham, Giang T.;Wang, Ben;Kim, Sang-Woo
    • Composites Research
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    • v.22 no.6
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    • pp.1-6
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    • 2009
  • This paper presents an experimental study on the piezoresistive behavior of nanocomposite strain sensors subjected to various loading modes and their capability to detect structural deformations and damages. The electrically conductive nanocomposites were fabricated in the form of a film using various types of thermoplastic polymers and multi-walled carbon nanotubes (MWNTs) at various loadings. In this study, the nanocomposite strain sensors were bonded to a substrate and subjected to tension, flexure, or compression. In tension and flexure, the resistivity change showed dependence on measurement direction, indicating that the sensors can be used for multi-directional strain sensing. In addition, the sensors exhibited a decreasing behavior in resistivity as the compressive load was applied, suggesting that they can be used for pressure sensing. This study demonstrates that the nanocomposite strain sensors can provide a pathway to affordable, effective, and versatile structural health monitoring.

Microstructure and Electromagnetic Characteristics of MWNT-filled Plain-Weave Glass/Epoxy Composites (다중벽 탄소나노튜브가 첨가된 평직 유리섬유/에폭시 복합재료의 미세구조 및 전자기적 특성)

  • Lee, Sang-Eui;Park, Ki-Yeon;Lee, Won-Jun;Kim, Chun-Gon;Han, Jae-Hung
    • Composites Research
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    • v.19 no.1
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    • pp.36-42
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    • 2006
  • MWNT(multi-walled carbon nanotube)-filled plain-weave glass/epoxy composites were fabricated and electromagnetic characteristics of the composites were investigated. The observation of the microstructures of the composites revealed that MWNTs are mostly distributed in matrix rich region and the interface between glass fiber yarns in warp and fill direction. The permittivity of the composites, measured in X-band (8.2-12.4 GHz) frequency range, increased with weight fraction of MWNTs and remained almost constant with frequency. The measured permittivity was used to investigate the reflection loss of radar absorbing structures (RAS) composed of MWNT-filled composites according to thickness and a RAS were constructed with 10 dB absorbing bandwidth 4.2 GHz and 3.3 mm in thickness.

Ag nanocrystal growth energy calculation

  • Jo, Min-Seung;Gang, Seong-U;Kim, U-Yeon
    • Proceeding of EDISON Challenge
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    • 2015.03a
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    • pp.156-162
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    • 2015
  • 나노입자의 특성과 기능은 bulk 물질과 달리, 나노 입자를 이루는 원소의 종류 뿐만아니라 크기와 모양에도 밀접한 연관이 있다. 이를 계산화학적으로 예측할 수 있다면 나노입자의 합성과 응용에 큰 도움이 될 것이다. 본 연구에서는 일정한 크기의 은 나노입자의 구조를 계산한 뒤, 바깥쪽의 두 원자 층을 무작위로 섞은 뒤 다시 구조최적화 계산을 거쳐 다양한 나노입자들의 구조를 찾았다. 이렇게 구해진 구조들의 에너지를 계산하고 원자를 하나 떼어낼 때의 에너지를 계산하여 응집 에너지를 구해 경향성을 분석해 보았다. 더 나아가, 나노입자를 이루는 각 원자 층의 개수가 하나 더 커질 때 필요한 에너지를 계산하여, 원자 하나당 평균을 내어 분석해보았다. 본 연구에서는 병렬화 된 밀도범함수이론 계산 프로그램을 이용해 100개가 넘는 입자의 계산이 가능하다는 것을 확인했고, 은 나노입자의 크기가 증가함에 따라 원자 하나가 추가되는 경우와, 원자 층 하나가 추가되는 경우의 그래프를 보고 경향성을 분석하였다. 이는 다른 화학적 환경에 있는 은 원자의 에너지를 계산하여 각각의 환경에서의 은 나노 입자의 크기를 예측하는 계산하는 데 초석이 될 것이다.

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A Recent Research Trends for Food Emulsions using Pickering Stabilization of Nano-particles (나노 입자의 피커링 안정화를 이용한 식품 에멀젼의 최근 연구동향)

  • Cho, Wan-Goo
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.2
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    • pp.238-247
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    • 2012
  • Nanotechnology in the food industry is an emerging area with considerable research and potential products. Solid particles of nanoscale and microscale dimensions are becoming recognized for their potential application in the formulation of novel dispersed systems containing emulsified oil or water droplets. This review describes developments in the formation and properties of food-grade emulsion systems based on edible fat crystals, silica nanoparticles, and novel particles of biological origin nanocrystals. The special features characterizing the properties of Pickering stabilized droplets are focused in comparison with those of protein-stabilized emulsions. We also review describes application examples of these in the food industry.

Fabrication of Triboelectric Nanogenerator based on a Composite of P(VDF-TrFE)/Graphene Flower (P(VDF-TrFE)/그래핀플라워 복합소재 기반 마찰전기 나노발전기 제작)

  • Muhammad Saqib;Woo Young Kim
    • Journal of the Korean Applied Science and Technology
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    • v.40 no.4
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    • pp.913-923
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    • 2023
  • In this study, a triboelectric nanogenerator was fabricated using the composite of teflon-based polymer and graphene flower, which are stable in air and have relatively high electronegativity. The composite was used to fabricate an electronegative layer of a nanogenerator using a spin-coating method. For the electropositive layer, a zinc oxide film was prepared using a sol-gel method. The fabricated triboelectric nanogenerator produced a maximum power of about 44 ㎼. In conclusion, since all the active layers of the triboelectric nanogenerator was made by the solution process, it is scalable to a large area.

ICT Convergenced Cascade-type Incubator for mass production of microalgae (미세조류 대량생산을 위한 ICT 융합 계단식 연속 배양 장치)

  • Lee, Geon Woo;Lee, Yong Bok;Yoo, Yong Jin;Baek, Dong Hyun;Kim, Jin Woo;Kim, Ho Seob
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.5
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    • pp.379-386
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    • 2021
  • This study was undertaken to develop a cascade-type continuous culture system (CCCS) that combines both ICT and biotechnology (BT), for the mass production of microalgae. This system is capable of maintaining the essential culture conditions of pH, temperature, carbon dioxide, and illuminance control, which are key parameters for the growth of microalgae, and is economical for producing microalgae regardless of the season or location. It has the added advantage of providing stable and high productivity. In the current study, this system was applied to culture microalgae for 71 days, with subsequent analysis of the experimental data. The initial O.D. of the culture measured from incubator 1 was 0.006. On the 71st day of culture, the O.D.s obtained were 0.399 (incubator 1), 0.961 (incubator 2), 0.795 (incubator 3), and 0.438 (incubator 4), thereby confirming the establishment of continuous culture. Thus, we present a smart-farm based on ISMC (in-situ monitoring and control) for a mass culture method. We believe that this developed technology is suitable for commercialization, and has the potential to be applied to hydroponics-based cultivation of microalgae and cultivation of high-value-added medicinal plants as well as other plants used in functional foods, cosmetics, and medical materials.