• 제목/요약/키워드: property SU

검색결과 934건 처리시간 0.032초

Transparent Conductive Films Composite with Copper Nanoparticle/Graphene Oxide Fabricated by dip Process and Electrospinning

  • 김진운;김경민;김용호;김수용;조수지;이응상;석중현
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.382.2-382.2
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    • 2014
  • We explain a method to fabricate multi-layered transparent conductive films (TCF) using graphene oxide (GO), copper powder and polyurethane (PU) solution. The flexible graphene nanosheets (GNSs) serve as nanoscale connection between conductive copper nanoparticles (CuNps) and PU nanofibers, resulting in a highly flexible TCF. To fabricate conductive films with high transmittance, polyurethane (PU) nanofibers were used for a conductive network consisting of CuNps and GNSs (CuNps-GNSs). In this experiment, copper powder and graphene oxides were mixed in deionized water with the ultrasonication for 2 h. NaBH4 solution is used as a reduction agents of CuNps and GNSs (CuNps-GNSs) under a nitrogen atmosphere in the oil bath at 100% for 24 h to mixed. The purified and dispersed CuNp-GNS were obtained in deionized water, and diluted to a 10wt.% based on the contents of GNSs. Polyurethane (PU) nanofibers on a PET substrate were formed by electrospinning method. PET slides coated with the PU nanofibers were immersed into CuNp-GNS solution for several second, rinsed briefly in deionized water, and dried to obtain self-assembled CuNp-GNS/PU films. The morphology of the multi-layered films were characterized with a field emission scanning electron microscope (FE-SEM, Hitachi S-4700) and atomic force microscope (AFM, PSIA XE-100). The electrical property was analysed by the I-V measurement system and the optical property was measured by the UV/VIS spectroscopy.

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$Y_1Ba_2Cu_3O_{7-y}$-Ag의 초전도성과 미세구조의 특성 연구 (A Study on Characteristic of Superconductivity and Microstructure of $Y_1Ba_2Cu_3O_{7-y}$-Ag)

  • 김채옥;박정수;유덕수
    • 한국재료학회지
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    • 제5권7호
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    • pp.786-793
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    • 1995
  • Ag를 $Y_1$Ba$_2$Cu$_3$O$_{7-y}$에 첨가하여 고상반응법으로 시료를 제작, Ag가 $Y_1$Ba$_2$Cu$_3$O$_{7-y}$의 고온초전도성과 그의 미세구조에 미치는 영향을 조사하였고 그에 따른 기계적 특성을 연구하였다. Ag의양이 증가함에 따라 결정립의 크기가 증가하였고 연결성이 향상되어 시료의 결정구조가 치밀해지고 단단해졌으며 결정립간의 weak link와 weak coupling을 줄이고 균일한 초전도 상을 형성시킨다는 것을 알 수 있었다. 또한 $Y_1$Ba$_2$Cu$_3$O$_{7-y}$결정구조의 이방성을 줄였고 $Y_1$Ba$_2$Cu$_3$O$_{7-y}$의 열적 안정성을 향상 시켰음을 알 수 있었다. 그리고 Ag의 첨가에 따라 시료의 기계적 강도가 증가함을 보였다.가함을 보였다.

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시멘트 수밀성에 대한 불소계 에멀젼의 영향 (The Effect of Fluorine Based Emulsion on the Watertightness Properties of Portland Cement)

  • 강현주;송명신;송수재;박수행
    • 공업화학
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    • 제20권5호
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    • pp.505-510
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    • 2009
  • 콘크리트의 내구성에 대한 대표적인 물리적 특성인 압축강도, 투수성능, 수밀성 등은 시멘트 재료의 미세구조에 의해 영향을 받는다. 특히 콘크리트의 내구성 향상을 위해서는 수밀성이 가장 중요하다 할 수 있다. 콘크리트의 수밀성 향상을 위한 재료는 유기 재료 및 무기질 재료가 다양하게 이용이 되고 있다. 본 연구에서는 불소계 에멀젼이 시멘트 수밀성능에 미치는 영향을 검토하였다. 불소계 에멀젼이 혼입된 시멘트 재료는 시멘트 계면 활성에 의한 수밀성능 개선 및 시멘트 pore 내에서 $CaF_2$ 미세 결정의 생성에 의해 시멘트 재료의 수밀성능을 개선시킬 수 있는 것으로 나타났다.

황제내경(黃帝內徑)의 오행귀류(五行歸類)에 관한 고찰(考察) (A study of Hwang Jae Nae Kyung(黃帝內經)'s O Haeng Kui Ryoo(五行歸類))

  • 김헌관;홍원식
    • 대한한의학원전학회지
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    • 제9권
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    • pp.654-699
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    • 1996
  • By studying Hwang Jae Nae Kyung(黃帝內經)'s O Haeng Kui Ryoo(五行歸類) in view of Chinese-Ancient-Thought like Chun In Hap Il Lon(天人合一論). Um Yang O Hang Lon(陰陽五行論). The theory of the month's age the conclusion is reached as follows 1. Chun In Hap Il Lon(天人合一論) means naturally men and nature consist of one energy to counteract each other and then developed to be concidered that the change of men and nature is same one;that is the basic thought of Hwang Jae Nae Kyung(黃帝內經) 2. Um Yang(陰陽) stands originally for the bright and the dark by sunrise or sunset. Ju Yuk Gye Sa Jun(周易繫辭傳) ahs considered Um Yang(陰陽) as the energy to explain changes of nature. O Haeng(五行) meaned originally five necessary materials or stuffs for living and then Chu Yun(鄒衍) has considered the difference between five powers in the nature through the combination with thought of O Haeng(五行). Hwang Jae Nae Kyung(黃帝內經) writes in the viewpoint of Um Yang O Haeng(陰陽五行) to analyze the changes of men and nature effectively. 3. O Haeng Kui Ryoo(五行歸類) is originated from Sang Su Hong Bum(尙書洪範) and its concrete examples are found in Kwan Ja(管子) and Yu SSi Chun Chu(呂氏春秋). O Haeng Kui Ryoo(五行歸類) in Hwang Jae Nae Kyung(黃帝內經) is widly affected by Kwan Ja O Haeng(管子五行) and adopts the opinion of Kum Mun Kyung Hak(今文經學) because of the background of times and medical physiology. 4. Hwang Jae Nae Kyung(黃帝內經) thinks that O Haeng(五行) means Mok(木) is the energy of being born, Hwa(火) growing-up, Kum(金) accumulating, Su(水) concluding, To(土) devoloping. O Haeng Kui Ryoo(五行歸類) in the heaven and the earth is classified by the property of O Haeng(五行). 5. O Haeng Kui Ryoo(五行歸類) in men can be explained so rationally with the property of O Haeng(五行) and the thery of an organism studied.

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조선시대 문헌에 나타난 가족경제생활관 (Home Economic View in Literatures and Documents of Cho-sun Dynasty)

  • 이길표
    • 가정과삶의질연구
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    • 제13권4호
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    • pp.115-124
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    • 1995
  • The purpose of this study was to accept its contents as lessons for today and to search for the correct way to lead home economy of the future by way of retranslating home economic view in literatures and documents of Cho-sun Dynasty(1392-1910) Through studying Cho-sun's literatures and documents: 「Ne-hun」 by the queen So He 「Kyou-dyoung-yo-ram」by Lee Whang 「Kyung-mong-yo-kul」by Lee Yul 「Song-ho-sa-sul」by Lee IK 「Sa-so-jol」by Lee Duk Moo「Buk-hak-ee」 by Park Je Ka 「Mok-min-sim-su」 by Jung Yak Yong. The results of this study can be summarized as follows : 1. The view of income: 1) Cut down on the too much greed of property (property income) 2) Work hard with diligence(earned income). 2. The view of expense : 1) Get food clothing and housing with frugality 2) Spend money for home rites and reception of guests with manner and truth without extravagnace. 3. The view of buying and selling: Buy and sell with credit. 4. The view of borrowing and lending: Borrow and lend money honestly,. 5. The view of home book-keeping : Keep home book-keeping every day. 6. The view of economic preparation : Save for a rainy day wisely.

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히스테리시스 특성이 계열연상에 미치는 영향에 대한 통계 신경역학적 해석 (Analysis of Statistical Neurodynamics for the Effests of the Hysteretic Property on the Performance of Sequential Associative Neural Nets)

  • 김응수;오춘석
    • 한국정보처리학회논문지
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    • 제4권4호
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    • pp.1035-1045
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    • 1997
  • 신경회로망의 동작과 정보처리 능력 등에 관하여 살펴보고자 할 때, 신경회로망의 구성 요소를 어떻게 모델화 할 것인가를 중요한 문제이다. 소자의 응답특성이 바뀜에 따른 특성의 변화, 결합강도 및 적용규칙이 바뀜 으로써 회로망 전체의 다이나믹스가 바 뀌는 모습, 소자 상호간의 결합 형태에 따른 정보처리 능력의 변화등과 같은 신경회로 망이 가진 다양한 정보처리 능력을 밝히는 것은 병렬 정보처리의 메카니즘을 이해하는 문제와도 일맥 상통하고 있다. 따라서 이러한 문제에 대하여 신경회로망의 정보처리 능력을 해석 적으로 평가하는 것은 병렬분산 정보처리의 본질을 밝힌다는 측면과 지적 정보처리 시스템의 구측을 목표로 연구되고 있는 신경회로망의 본질을 이해한다는 측면에서도 중요하게 여겨진다. 따라서 본 논문에서는 신경회로망을 구성하는 구성요 소의 변화, 그 가운데에서도 특히 소자의 히스테리시스 특성이 신경망의 계열연상 능력에 따라 미치는 영향에 대한 이론적 해석결과에 대하여 기술한다.

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Study on Corrosion Properties of Additive Manufactured 316L Stainless Steel and Alloy 625 in Seawater

  • Jung, Geun-Su;Park, Yong-Ha;Kim, Dae-Jung;Lim, Chae-Seon
    • Corrosion Science and Technology
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    • 제18권6호
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    • pp.258-266
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    • 2019
  • The objective of this study was to evaluate corrosion resistance of additive manufactured 316L stainless steel and alloy 625 powders widely used in corrosion resistance alloys of marine industry in comparison with cast alloys. Directed Energy Deposition (DED) method was used in this work for sample production. DED parameter adjustment was also studied for optimum manufacturing and for minimizing the influence of defects on corrosion property. Additive manufactured alloys showed lower corrosion resistance in seawater compared to cast alloys. The reason for the degradation of anti-corrosion property was speculated to be due to loss of microstructural integrity intrinsic to the additive manufacturing process. Application of heat treatment with various conditions after DED was attempted. The effect of heat treatments was analyzed with a microstructure study. It was found that 316L and alloy 625 produced by the DED process could recover their expected corrosion resistance when heat treated at 1200 ℃.

고주파 영역에서의 MR 유체 특성연구 (Material Characterization of MR Fluids at High Frequencies)

  • 박경미;김재환;최승복;김경수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 추계학술대회논문집
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    • pp.210-215
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    • 2002
  • MR(Magnetorheogical) fluid composed of fine iron powders dispersed in silicon oil is utilized to many smart structures and devices because of its significant rheological property change by the application of an external magnetic field. When we deal with the shock wave attenuation of warship structures, we should be able to characterize the high frequency behavior of MR fluids. So far, however, many efforts have been focused on the material characterization of MR fluids at low frequencies below 100Hz. In this paper, the MR fluid property characterization at high frequency region is performed. An experimental setup based on wave transmission technique is made and the storage modulus as well as the loss modulus of MR fluids are found from the measured data of speed sound and attenuation. Details of the experiment are addressed and the obtained storage and loss moduli are addressed at $50kHz{\sim}100kHz$.

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STUDY ON OPTICAL PROPERTY OF RED TIDE ALGAL SPECIES

  • Lee, Nu-Ri;Ahn, Yu-Hwan;Moon, Jeong-Eon;Yang, Chan-Su;Yoon, Hong-Ju
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.324-327
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    • 2006
  • This research is about the optical characteristic of red tide which is collected from Nam-Hae for basic research of red tide remote sensing technique development. 21 kinds of red tide organisms are cultivated to investigate optical characteristic of them on the level of laboratory, and chlorophyll specific absorption coefficient($a^*$) and backscattering coefficient($b_b^*$) are estimated by using spectrophotometer. Absorption spectrums according to species are appeared diversely from 0.005 to 0.06 (mg/ $m^2$), and the shapes of spectrums are also different. The range of $b_b^*$ are appeared $10^{-2}{\sim}10^{-4}$ mg/ $m^2$, which have around 100 times differences between species, and the shape of spectrum also have significant difference between species. These results are able to use as an input data of inverse model from ocean color.

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침향(沈香)의 침수성(沈水性)에 관한 문헌적 연구 (A Philological study on Submersion Property of Aquilariae Lignum)

  • 박수진;김인락
    • 대한본초학회지
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    • 제27권4호
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    • pp.25-31
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    • 2012
  • Objectives : The purpose of this study is searching for grounds of new regulations about submerging properties of Aquilariae Lignum described in the Korean Herbal Pharmacopoeia. Methods : Through the investigation of the various Chinese histories and herbal classics, the definitions of Aquilariae Lignum and documents on actual trade and discrimination methods by sinking under water. Results : In Jiaozhouyiwuzhi(交州異物志) written in the early 2nd century, Aquilariae Lignum was defined as heart wood part or knots sinking under water due to hard and dark deposition of resins. Also, which are not sinking were defined as zhan xiang(棧香), and which are floating were named as qian xiang(槧香). The definitions of Aquilariae Lignum had not been changed till Ching Dynasty era, but the classification and the names about not-sinking and floating Lignum materials were a little changed. Conclusions : These results indicate that it is reasonable to make a regulation that "Aquilariae Lignum sinks under water" in the property description of The Korean Herbal Pharmacopoeia.