• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.160-162
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• 2004

기계적, 열적 강도가 우수한 무기막과 다양한 기능성을 가질 수 있는 유기막의 결합에 관하여 그동안 많은 연구가 진행되어왔다. 무기막은 높은 열적, 기계적 안정성을 가지고 있기 때문에 지지체로써 큰 이점을 가지고 있으며, 고분자를 비롯한 유기막은 그 다양성과 응용성에 있어 장점을 가지고 있다. 이에 본 연구는 지지체로써 물성이 뛰어난 세라믹막의 표면에 다양한 유기 기능기를 가지는 실란화합물을 그래프팅 방법을 통하여 도입하여 유-무기 혼성막을 제조하고 표면 특성의 변화를 살펴보고자 하였다.(중략)

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1993.07a
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• pp.55-58
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• 1993

유공식 방파제는 기존 직립 혼성방파제의 케이슨 전면에 유공벽과 유수실을 설치함으로써 교량이 유공벽을 통과하여 유수실내로 진입할 때 와유 등에 의해 접근 파랑에너지를 감소시킬 수 있도록 고안된 구조형식을 갖는다. 따라서, 방파제 주변의 항로유지에 있어서 기존 직립 혼성방파제에 비해 우수한 특성을 지닌 형태이다. 이러한 방파제 형태는 일본에서는 다수 시공되어 성공적으로 운영되고 있으나 국내에서는 아직도 이렇다 할 시공실적이 없다. (중략)

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.719-723
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• 2005

Organic-inorganic hybrid mesoporous materials were prepared by co-condensation of organosilanes with tetraethyl orthosilicate (TEOS) or 1,2-bis(triethoxysilyl) ethane (BTSE). Their removal capability of volatile organic compounds (VOCs) in the air was evaluated and compared with that of inorganic hydrophilic mesoporous material, SBA-15 that was prepared with TEOS only. It was found that the increased hydrophobicity of mesoporous materials due to the presence of organic group, could enhance the VOCs removal by adsorption in the air. An organic-inorganic hybrid material prepared by the co-condensation of BTSE/phenyl triethoxysilane (90/10 by weight) was a typical example of superior adsorbent. It was also observed that these organic-inorganic hybrid materials can be utilized as absorbents for the removal of oil dispersed in water.

• Journal of the Mineralogical Society of Korea
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• v.13 no.2
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• pp.96-114
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• 2000

춘천 연옥은 색깔에 따라 세가지 유형 (연녹색, 암녹색, 및 회색 연옥)으로 구분되고 이들은 각기 서로 다른 조직과 조성을 나타낸다. 연녹색 연옥이 이중에서 가장 일반적인 유형이다. 연옥은 주로 극미립의 연옥질 투각섬석으로 구성되고 여기에 미량의 휘석, Mg-녹니석 및 방해석이 불순물로서 수반된다. 연옥질 투각섬석 결정들은 그 폭이 5$\mu\textrm{m}$ 이하의 극미립질 침상 결정형을 이루며 서로 치밀하게 얽혀있는 연옥 특유의 조직을 나타낸다. 주사전자현미경 하에서 (110)의 벽개면의 발달이 현저하고, 주사탐침현미경 하에서는 벽개면을 가로지르는 방향으로 특징적인 조선이 나타나는 것이 특징이다. 연옥질 투각섬석은 투과전자현미경 하에서 흔히 단쇄형과 복쇄형이 결합한 3중쇄형 격자가 복쇄형의 투각섬석 구조 내에서 불규칙적으로 협재되는 혼성격자 구조가 발달하는 것이 특징이다. 드물지만 5중쇄형 격자와 4중쇄형 격자도 관찰되는데, 이 같은 불규칙한 격자 혼재상은 회색 연옥에서 보다 현저한 경향을 보인다. 이와 같은 혼성격자 구조형의 존재는 춘천 연옥이 열역학적으로 비평형 상태에서 형성되었음을 시사하는 것으로 여겨진다. 리트벨트법에 의한 구조검증을 통해서 구해진 연옥질 투각섬석들의 격자상수 값들은 X-선회절의 경우, a=9.837(1)~9.9804(4)$\AA$, b=18.046(2)~18.062(1)$\AA$. c=5.2765(7)~5.2803(3)$\AA$, $\beta$=104.717(9)~104.786(3)$^{\circ}$로 계산되었다. 이에 비해서 중성자 회절법에 의해서 측정되 격자 상수 값은 a=9.8841(6)~9.8933(7)$\AA$, b=18.1429(7)~18.161(2)$\AA$, c=5.3024(3)~5.3060(7)$\AA$, $\beta$=104.698(7)~104.771(4)$^{\circ}$로서 X-선회절에 의한 값들과 약간의 차이를 보인다. 연옥질 투각섬석은 Ca에 대한 Mg의 치환에 의해 M(4) 자라의 크기가 작아지면서 b축의 단위포도 함께 줄어드는 결정화학적 특징을 나타낸다. 이는 중성자 회절분석에 의해서 구해진 M(4)의 자리점유율과 M(4)-O의 원자간 거리에 의해서도 확인된다. 그러나 연옥질 투각섬석에 대한 리트벨트법에 구조검증 결과는 연옥의 유형별 미시적 광물상과 혼성격자 구조형의 특징에 별다른 연계성이 없는 것으로 나타났다.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.632-638
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• 2012

Waterborne polyurethane dispersions (PUD) were synthesized from isophorone diisocyanate (IPDI), polycarbonate diol (PCD) and dimethylol propionic acid (DMPA) as starting materials. Subsequently, waterborne polyurethane-acrylic hybrid solutions were prepared by reacting the PUD with different amounts of the mixture of acrylate monomers, HEMA (2-hydroxyethyl methacrylate) and MMA (methyl methacrylate). As a result, the average particle size of waterborne polyurethane-acrylic hybrid solutions was increased with increasing the addition amounts of acrylate monomers. Also, the prepared coating films from waterborne polyurethane-acrylic hybrid solutions showed better abrasion resistance and chemical resistance than those of pure PUD.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.6
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• pp.759-768
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• 2019

The extended Tanimoto formula has been widely used to estimate the stability for the toe protection of the composite structure. However, the extended Tanimoto formula usually over-estimates armor weight when the incident waves approach the structure obliquely because the formula incident originally considered the normally incident wave cases. In this study, three-dimensional hydraulic model experiments were conducted to investigate the horizontal wave velocity under monochromatic and random wave conditions to investigate the prediction capability of the extended Tanimoto formula under the different incident wave angle conditions. The maximum horizontal wave velocity was measured near the toe for the normally incident wave condition. In the case of obliquely incident waves, the maximum horizontal wave velocity was measured under the stem wave generation condition. The results of the experiments showed a good agreement with the results by Takahashi et al.

• Journal of the Korean Chemical Society
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• v.61 no.4
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• pp.204-210
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• 2017

In this study, we analyzed the descriptions of the electron movement model and the oxidation number change model presented in the 2009 revised curriculum and textbooks. We also investigated chemistry education major teachers' conceptions of limitations of each model. The electron movement model and oxidation number change model were presented in the curriculum and the textbooks. However, hybrid model was also presented which fail to grasp the limitation of each model. The hybrid model explains redox reactions of covalent bond compounds by electron movement model or even if it explains redox reactions by oxidation number change model, this explanations have the problem of confusing the virtual electron movement with the actual electron movement. A questionnaire and interviews were conducted to investigate chemistry education major teachers' perceptions of redox reactions. As results, many teachers did not recognize the limitations of each model and had difficulties to distinguish redox reactions from acid-base reactions because of the hybrid model.

• Journal of the Korean Ceramic Society
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• v.39 no.11
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• pp.1063-1068
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• 2002

Polyimide/silica(PI/silica) hybrid materials having physical or chemical bonds between the PI and silica network were prepared using sol-gel process through hydrolysis and polycondensation of tetraethoxysilane with the polyamic Acid(PAA) or end-capped PAA solution. PAA solution was synthesized by ring opening reaction of pyromellitic dianhydride and oxydianiline monomers in dimethyl acetamide solution. End-capped PAA solution was synthesized by the addition of 3-aminopropyltriethoxysilane in PAA solution. PI/silica hybrid samples were characterized by infrared spectroscopy, differential thermogravimetry, X-ray diffractometry, scanning electron microscopy, and tensile tester. It has been demonstrated that the properties of hybrid samples were affected by the silica content and the bond type between PI and silica.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.1156-1159
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• 2009

Since the middle of the 1960's, revitalization of the media art has showed a new paradigm shift as a alternative to existing art genre. According to advances in technology the form of art becomes various. Nowdays, art work which is mixed with media and other genre is popular because of hybrid culture. The image medium has flexibilty to incorporate with other genre because of medium character. The media installation that applied the image medium means to mixed work of sculpture and media. The sculpture and media has been broadened the field through the media installation. this study discuss art works projected image on sculpture among various media installation works. The materiality of the sculpture and the vision of the image mix up each other. It is associated with M. Merleau-Ponty's sens theory.

• The Journal of the Acoustical Society of Korea
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• v.26 no.1
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• pp.42-47
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• 2007

In this paper. we have studied improvement in sensitivity by increasing the frequency of SAW sensors for detecting the immobilization and hybridization of DNA. The sensor consists of twin SAW delay lines operating at 200MHz, a sensing channel and a reference channel. fabricated on $36^{\circ}$ rotated Y-cut X-propagation $LiTaO_3$ crystals. The optimum concentration of probe and target DNA was decided for the improvement of detection mechanism. and digital syringe pump system was used to reduce the human errors. The hybridization between immobilized probe DNA and target DNA on the gold-coated delay line results in mass loading on the delay line of the sensing channel. Thus, the relative frequency change was monitored in relation to the mass loading. The measurement results showed a good response of the sensor to the DNA hybridization with a maximum sensitivity level up to 0.066ng/m1/Hz.