• Defense and Technology
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• no.9 s.271
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• pp.39-49
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• 2001

미래에는 정보전자전을 대비해서 전자기펄스탄(EMP 탄), 탄소섬유탄, 고섬광 발생탄과 같이 물리화학적 파괴 능력을 갖는 특수 전용 탄두들이 소요될 것이다. 세계 대전의 가능성은 희박하나 지역분쟁이 발생했을 때 전후방과 군과 민이라는 구분이 없어지고, 전쟁상황이 실시간으로 전파되기 때문에 다양한 비살상 탄두가 주요 전술탄두로 등장할 수 있다. 따라서 전자기 펄스탄(EMP 탄), 탄소섬유탄과 같은 대 정보.전자전 탄두들이 우리가 미래를 대비하는 하나의 수단이 되리라 확신한다.

• Analytical Science and Technology
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• v.13 no.5
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• pp.573-583
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• 2000

Activated carbon fibers (ACFs) were prepared from various precursors of plantic, synthetic, and mixed fabrics of viscous rayon and cotton. Their adsorption performances of phenol and methylene blue in aqueous phase were evaluated through their adsorption isotherms, adsorption rates and breakthrough curves. The two adsorbates showed type I adsorption isotherm on ACFs. Adsorption rates to ACFs were 100 fold faster than to GAC. The effective diffusion coefficients of the adsorbates in ACFs were twenty fold greater than in GAC. The ACFs removed completely ten organic pollutants from a prepared water specimens through the 2nd column of a natural filtration method where 50 L of the water samples were treated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.5
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• pp.2439-2444
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• 2011

We investigated the adsorption/desorption property of volatile organic compounds(VOC) by using activated carbon fibers(ACF) instead of activated carbon(AC) which is conventionally used. The adsorption behavior of the fixed bed and the breakthrough characteristics were also studied. As a result, ACFj showed 1.15 times higher adsorption amount as compared to AC. The breakthrough Point and adsorption amount of VOCs were decreased with the increase of temperature. In the case of AC, desorption time having 99% removal efficiency was about as minutes, but that of ACF was about 5 minutes at same condition.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.277-285
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• 2007

The adsorption characteristics of multi-component solvent vapors including poorly-adsorbable chemicals such as toluene-xylene-MEK and toluene-MEK-IPA on the activated carbonaceous adsorbents were investigated in a stainless steel fixed bed of 10.2 cm ID and 50 cm in height in order to identify those carbons for eliminating and recovering solvent vapors from industrial emission sources. The used activated carbonaceous adsorbents were pelletized commercial activated carbons and activated carbon fiber. Breakthrough curves and adsorption capacity at atmospheric pressures were obtained. It has been found that non-polar and larger molecules have been adsorbed better than polar and smaller molecules. In special, alcohols and ketones were poorly adsorbed caused by competitive adsorbability in multi-component mixture system. However, it could be overcome by profitable employment of organization of cooperative system which was composed of different porosity activated carbonaceous adsorbents appropriately.

• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.669-675
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• 2006

Toluene of aromatic compounds, MEK of ketones and IPA of alcohols were extremely used as VOCs (Volatile Organic Compounds) on the getting into step with industrial process. The adsorption characteristics of three component solvent vapors (Toluene-MEK-IPA) on the activated carbonaceous adsorbents such as AC, ACF and AC+ACF were investigated in a stainless steel fixed bed adsorption experimental apparatus in order to identify those carbons for eliminating and recovering solvent vapors from industrial emission sources. The used activated carbonaceous adsorbents were pelletized commercial activated carbon and activated carbon fiber. The breakthrough curves and adsorption capacity have been obtained at atmospheric pressure in a adsorption fixed bed. It has been found that non-polar and larger molecules have been adsorbed better than polar and smaller molecules. Especially, alcohols and ketones were poorly adsorbed due to competitive adsorbability in ternary mixture system. However, it could be overcome by employment of activated carbonaceous adsorbent which have different porosity distribution appropriately.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.267-270
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• 1997

악취 물질은 주로 정유공장, 분뇨 처리장, 축산$\cdot$수산 가공업, 화학공장 등에서 발생하며 작업장 내의 직원 뿐만 아니라 인근 지역주민들에게 정신적인 불쾌감을 주는 동시에 인체에 매우 유해한 물질들이다. 이들 악취의 주성분은 메틸머켑탄, 황화수소, 암모니아, 트리메틸아민 등의 물질이다. 이들 물질의 제거 방법에는 약액세정법, 직접연소법, 활성탄흡착법 등이 있다. 이중 활성탄 홉착법은 설비비와 운영경비상의 잇점으로 오랫동안 사용되어져 왔고, 현재도 악취가 많이 발생하는 사업장의 악취 제거 방법으로 널리 사용되고 있다. 그러나 기존의 활성탄을 이용한 흡착제거는 처리효율이 낮고, 이에 따른 흡착제의 충진량이 많아지고 시설용량이 커지는 등의 결점이 있다. 이러한 문제점을 해결하기 위해 활성탄의 성질의 개선과 ACF와 같은 흡착제의 활용등에 대한 연구들이 진행되고 있다. (중략)

• Journal of the Korean Ceramic Society
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• v.36 no.10
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• pp.1016-1021
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• 1999

In this study activated carbon fibers were prepared from PAN-based carbon fibers by physical activation with steam or carbon dioxide. The variations in specific surface area amount of iodine adsorption and pore size distribution of the activated carbon fibers after the activation process were discussed. in steam activation BET surface area of about 1019 m2/g was obtained after 77% burn-off while carbn dioxide activation produced ACF with 694m2/g of BET surface area after 52% burn-off. However carbon dioxide activation produced at a similar degree of activation higher micropore volume(0.37 cc/g) and amount of iodine adsorption (1589mg/g) than steam activation. Nitrogen adsorption isotherms for (PAN based activated carbon fibers that prepared by physical activation were of type I in the Brunauer-Deming-Deming-Teller classification

• Composites Research
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• v.35 no.2
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• pp.106-114
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• 2022

Carbon fiber-reinforced plastic, well known high specific strength and high specific stiffness, have been widely used in the aircraft industry. Mostly the CFRP structure is fabricated by lamination of carbon fiber or carbon prepreg, which has major disadvantage called delamination. Delamination is usually produced due to absence of the through-thickness direction fiber. In this study, three-dimensional carbon preform woven in three directions is used for fabrication of aircraft wing unit structure, a part of repeated structure in aircraft wing. The unit structure include skin, stringer and rib were prepared by resin transfer molding method. After, the 3D structure was compared with laminate structure through compression test. The results show that 3D structure is not only effective to prevent delamination but improved the mechanical strength. Therefore, the 3d preform structure is expected to be used in various fields requiring delamination prevention, especially in the aircraft industry.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.5
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• pp.717-724
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• 2010

The initial trajectory of a spheroid configuration bobbin for precision guidance has been investigated by analyzing its aerodynamic load and six-degree-of-freedom motion. The effects of changes in the spheroidal head configuration, flow angle and lateral center-of-gravity offset are numerically studied using the commercial software "FLUENT". A wind tunnel test is also conducted to validate the numerical scheme and to examine effect of the Reynolds number on the flow around the bobbin. It is shown that the size of the separation bubble formed on the surface decreases significantly when the Reynolds number is varied between 110,000 and 140,000. At a zero flow angle, an oblate spheroidal head shows relatively moderate rotation while a prolate spheroidal head shows rapid rotation. The bobbin with a spherical head shape has little effect on the flow direction; however, the oblate bobbin is sensitive to the flow angle. The roll motion of the bobbin is greatly influenced by the lateral center-of-gravity offset and maximum dispersion is observed at half of the radius.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.2
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• pp.475-483
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• 2017

Geosmin and 2-methylisoborneol (2-MIB) produced by cyanobacteria during algal blooming in surface water are the major taste-and-odor-causing compounds in drinking water and need to be removed. Activated carbon is often used in treatment plants for the mitigation of odor problem. However, there is a lack of information on the effect of pore size distribution and particle size of activated carbon for adsorption of both odor compounds. Therefore, we studied the effect of pore size distribution and particle size of activated carbon on the adsorption of geosmin and 2-MIB. When comparing the adsorption of geosmin and 2-MIB between activated carbon fiber (ACF), powdered activated carbon (PAC) and granular activated carbon (GAC), the order of removal efficiency was PAC > ACF > GAC. As a result of comparing PACs with various pore distribution characteristics, well-developed micropores on activated carbon were found to be favorable for adsorption of geosmin and 2-MIB. For particle size, smaller was more effective for adsorption of geosmin and 2-MIB.