• Nano
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• 제13권10호
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• pp.1850113.1-1850113.11
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• 2018

Environmental and energy issues have always been a hot topic of global research. Oil leakage has caused great damage to the environment, affecting a wide area and it is difficult to clean up. In most cases, carbon-based adsorbents are typically utilized to remove oil spills because of their economic benefits and high adsorbent efficiency. At the same time, its excellent material properties can also be used for the preparation of supercapacitors. In this paper, the carbon aerogels were prepared by the one-step method. The prepared materials endowed a 3D network structure with a huge number of micropores and mesoporous, and the material is light-weight, stable, hydrophobic and has affinity for oil (17.02 g/g) to the KGM carbon aerogel. Through the physicchemical characterization, the KGM carbon aerogel shows specific surface area is $689m^2/g$, high water contact angle ($136.64^{\circ}$) and excellent reusability (more than 15 cycle times). In addition, we also discussed the electrochemical properties of the material and obtained the specific electrical capacity of 139 F/g under the condition of 1 A/g.

• Steel and Composite Structures
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• 제31권6호
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• pp.559-573
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• 2019

Spiral spacing effect on axial compressive behavior of reinforced concrete filled steel tube (RCFST) stub column is experimentally investigated in this paper. A total of twenty specimens including sixteen square RCFST columns and four benchmarked conventional square concrete filled steel tube (CFST) columns are fabricated and tested. Test variables include spiral spacing (spiral ratio) and concrete strength. The failure modes, load versus displacement curves, compressive rigidity, axial compressive strength, and ductility of the specimens are obtained and analyzed. Especially, the effect of spiral spacing on axial compressive strength and ductility is investigated and discussed in detail. Test results show that heavily arranged spirals considerably increase the ultimate compressive strength but lightly arranged spirals have no obvious effect on the ultimate strength. In practical design, the effect of spirals on RCFST column strength should be considered only when spirals are heavily arranged. Spiral spacing has a considerable effect on increasing the post-peak ductility of RCFST columns. Decreasing of the spiral spacing considerably increases the post-peak ductility of the RCFSTs. When the concrete strength increases, ultimate strength increases but the ductility decreases, due to the brittleness of the higher strength concrete. Arranging spirals, even with a rather small amount of spirals, is an economical and easy solution for improving the ductility of RCFST columns with high-strength concrete. Ultimate compressive strengths of the columns are calculated according to the codes EC4 (2004), GB 50936 (2014), AIJ (2008), and ACI 318 (2014). The ultimate strength of RCFST stub columns can be most precisely evaluated using standard GB 50936 (2014) considering the effect of spiral confinement on core concrete.

• 한국수산과학회지
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• 제52권1호
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• pp.35-42
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• 2019

We investigated the protective effects of antioxidant fractions from a 70% ethanolic extract of Hizikia fusiformis in human dermal fibroblasts (HDFs). Powdered H. fusiformis was extracted with 70% ethanol and then partitioned into three fractions according to polarity using n-hexane (HFH), chloroform (HFC), and ethyl acetate (HFEA). Antioxidant activity was observed in HFEA at 0.66 mg/mL based on the half maximal inhibitory concentration ($IC_{50}$) of 1,1-diphenyl-2-picrylhydrazyl (DPPH), and at 0.24 mg/mL based on alkyl radical scavenging. The protective effects of the HFEA antioxidant fraction against 2,2-azobis-(2-amidinopropane) dihydrochloride (AAPH)-damaged HDFs and the expression of Type I procollagen in HDFs were examined. HFEA caused the proliferation of HDFs with and without AAPH treatment and protected against AAPH damage to HDFs in a dose-dependent manner ($50-200{\mu}g/mL$). This implies that the antioxidant properties of the fractions depended on their proliferative and protective effects. The HFEA antioxidant fraction had significant effects and caused the dose-dependent expression of Type I procollagen, an important anti-wrinkle protein, in HDFs. In conclusion, antioxidant substances in H. fusiformis were found in the ethyl acetate fraction, and the resulting HFEA may have cosmetic applications.

• Journal of the Korean Wood Science and Technology
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• 제49권6호
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• pp.658-666
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• 2021

A novel flame retardant and antibacterial composite membrane coating for wood surfaces was prepared by adding POSS-based phosphorous nitrogen flame retardant (later referred to as NH₂-POSS) and silver nanoparticles (Ag NPs) to chitosan (CS). The effects of NH₂-POSS content (mass fractions of CS 0%, 0.5%, 1%, 3%, 5%, and 7%) on the structure and properties of the composite membrane coating on wood were investigated. The composite film was prepared by the method of blending and ducting. Contact angle, tensile property and antibacterial effects of the composite film were measured, and infrared spectroscopy was used. The results show that the addition of NH₂-POSS can not only improve the toughness of the membrane, but also the flame retardancy of the membrane, which improves the application of the membrane in wood products. However, with the addition of NH₂-POSS, the transparency of the composite membrane was weakened. The inhibitory effect of the composite membrane on the growth of Escherichia coli was enhanced with the increase in Ag NPs. This research provides a foundation for the application of functional wood.

• Journal of the Korean Wood Science and Technology
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• 제49권6호
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• pp.667-678
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• 2021

The flame retardancy of plywood should be improved as much as possible while minimizing the impact on the bonding strength of plywood. Six commercial flame retardants and three laboratory synthesized phosphorous nitrogen flame retardants were selected. E₀, E₁ and E₂ grade commercial formaldehyde resins (UF) were applied in this study to evaluate the effect of different flame retardants on the curing time of resin, bonding strength, flame retardant performance, and formaldehyde emission of plywood. The results show that the effect of the addition of different flame retardants on the bonding strength of plywood gradually decreased with the increase of the formaldehyde molar ratio of the resin. The effect of flame retardants on the curing time of UF gradually decreased as the mole ratio of formaldehyde increasing, while the amount of formaldehyde emission varied according to the content of formaldehyde in the flame retardant. Compared with plywood without flame retardant, flame retardant of plywood added with phosphorous nitrogen flame retardant was improved.

• 한국융합학회논문지
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• 제11권12호
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• pp.79-87
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• 2020

최근 지역 문화 발전과 도시 다양성의 맥락에서 각각의 관광지들은 독특한 민속 문화를 발굴하여 관광객의 관심과 방문을 유도하고 있다. 지속 가능한 관광의 일환으로 미식 관광은 명승지 환경을 해치는 건설을 할 필요도 없고, 지역 주민과 관광객에게 서비스를 제공하기 위한 시설 개선 만하면 되는 장점도 있다. 그러나 기존의 미식 관광은 관광객을 풍속 현장에만 두게 되어 주체 간에 다른 문화적 차이를 넘어 민속 문화의 핵심을 체험할 수 없었다. 본 논문은 관찰 방법, 융복합 주제 연구 및 사례 연구를 통해 민속 문화를 이해하는데 있어서 푸드 도슨트 가이드 투어의 역할을 연구하였다. 특히 도슨트 가이드 투어에서 미식 관광이 지속 가능 발전이라는 목표를 잘 달성할 수 있도록 가이드가 관광객들로 하여금 민속 문화의 핵심에 보다 효과적으로 동화되어 체험할 수 있도록 돕는 방법을 연구하였다.

• 디지털융복합연구
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• 제18권12호
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• pp.513-523
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• 2020

후(後)구조주의 철학자 질 들뢰즈(Gilles Deleuze)는 감각과 신체에 대한 논의를 심층적으로 전개한 바 있다. 본 연구에서는 들뢰즈의 신체 미학의 핵심 사상, 즉, 기관 없는 신체이론을 기초로 현대 패션과 그 신체와의 관계를 재해석한다. 본 연구의 결과는 다음과 같다. 첫째, 기관 없는 신체는 그 강도에 따라 '충만한 기관 없는 신체'와 '텅 빈 기관 없는 신체' 그리고 '암적인 기관 없는 신체'의 세 가지로 분류할 수 있다. 둘째, 현대 패션은 착용 방식의 변화에 따라 새로운 신체관계를 창조할 수 있고 충만한 기관 없는 신체를 형성할 수 있다. 셋째, 텅 빈 기관 없는 신체 상태에서는 옷을 훼손함으로써 부정적인 의미의 암적인 기관 없는 신체를 만들 수 있다. 현대 패션디자인에 반영된 들뢰즈의 기관 없는 신체론과 강도 분석을 통해, 신체와 의복의 상관관계를 더욱 깊이 이해하고, 이를 통해 패션디자이너들의 창의적 표현의 근간이 되기를 바란다.

• 디지털융복합연구
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• 제18권12호
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• pp.549-563
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• 2020

본 연구는 들뢰즈의 신체 미학을 바탕으로 탈영토화의 관점에서 분석하고 현대 패션디자인의 작품 속에 내재되어있는 시각화특징이 히스테리, 형상화. 신체분해, 동물-되기 등 4가지 특성으로 신체 개조, 즉 패션조형화, 예술화 됨을 심층적으로 검토하였다. 첫째, 히스테리는 패션 디자인에서 의상의 변형과 과장이 주는 강렬한 시각적인 효과를 보여준다. 둘째, 형상화가 패션에서의 표현은 가면이 얼굴을 제거하거나 의상구조 등은 얼굴을 희미하게 해주는 두 가지 분야다. 이는 신원의 약화와 의상 및 신체를 돋보이게 한다. 셋째, 신체 분화는 의상의 구조 해체와 재구성을 의미하며 새로운 사고방식을 표현한다. 넷째, 동물-되기는 동물 그림의 활용과 사람과 동물 사이의 이질적인 연결에 따른 형체 돌연변이를 보여줌으로써 신체를 다시 생각할 수 있는 가능성을 보여준다.

• Geomechanics and Engineering
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• 제24권6호
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• pp.573-588
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• 2021

The interaction of cracks and water significantly affects the fracture mechanism of rocks. In this study, laboratory tests were conducted using sandstone samples containing a single fissure to explore the hydro-mechanical behaviors in the failure process of pre-cracked rocks. The internal crack characteristics were also analyzed using X-ray CT scanning. The results show that the confining pressure has the greatest effect on the mechanical properties (e.g., strengths, elastic modulus, and Poisson's ratio), followed by the fissure inclination and water pressure. At a lower fissure inclination, the confining pressure may control the type main cracks that form, and an increase in the water pressure increases the number of anti-wing cracks and the length of wing cracks and branch cracks. However, the fracture behaviors of samples with a higher fissure inclination are only slightly affected by the confining pressures and water pressures. The effect of fissure inclination on the internal crack area is reduced with the propagation from the fissure tips to the sample ends. The fissure inclination mainly affects the value of permeability but not affect the trend. The impact of pre-existing fissure on permeability is smaller than that of confining pressure and water pressure.

• Animal Bioscience
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• 제35권2호
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• pp.166-176
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• 2022

Objective: Sperm is particularly susceptible to reactive oxygen species (ROS) stress. Glutathione (GSH) is an endogenous antioxidant that regulates sperm redox homeostasis. However, it is not clear whether boar sperm could utilize cysteine for synthesis GSH to protect sperm quality from ROS damage. Therefore, the present study was undertaken to elucidate the mechanism of how cysteine is involved in protecting boar sperm quality during liquid storage. Methods: Sperm motility, membrane integrity, lipid peroxidation, 4-hydroxyIlonenal (4-HNE) modifications, mitochondrial membrane potential, as well as the levels of ROS, GSH, and, ATP were evaluated. Moreover, the enzymes (GCLC: glutamate cysteine ligase; GSS: glutathione synthetase) that are involved in glutathione synthesis from cysteine precursor were detected by western blotting. Results: Compared to the control, addition of 1.25 mM cysteine to the liquid storage significantly increased boar sperm progressive motility, straight-line velocity, curvilinear velocity, beat-cross frequency, membrane integrity, mitochondrial membrane potential, ATP level, acrosome integrity, activities of superoxide dismutase and catalase, and GSH level, while reducing the ROS level, lipid peroxidation and 4-HNE modifications. It was also observed that the GCLC and GSS were expressed in boar sperm. Interestingly, when we used menadione to induce sperm with ROS stress, the menadione associated damages were observed to be reduced by the cysteine supplementation. Moreover, compared to the cysteine treatment, the γ-glutamylcysteine synthetase (γ-GCS) activity, GSH level, mitochondrial membrane potential, ATP level, membrane integrity and progressive motility in boar sperm were decreased by supplementing with an inhibitor of GSH synthesis, buthionine sulfoximine. Conclusion: These data suggest that boar sperm could biosynthesize the GSH from cysteine in vitro. Therefore, during storage, addition of cysteine improves boar sperm quality via enhancing the GSH synthesis to resist ROS stress.