• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2002.05a
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• pp.209-213
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• 2002

최근 들어 메탄올 환원제로 사용하는 이산화탄소의 촉매 개질 반응이 많은 주목을 받고 있다. 메탄에 의한 이산화탄소의 개질 반응 시 생성되는 합성 가스는 기존의 수증기 개질 반응에서 생성되는 합성 가스에 비하여 $H_2$/CO의 비가 낮으며 직접 메탄올 및 DME와 같은 유용한 물질로의 전환이 유리하므로 이에 대한 연구가 활발히 진행 중에 있다.(중략)

• Elastomers and Composites
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• v.38 no.4
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• pp.326-333
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• 2003

Even though many studies have been reported about rubber vulcanization, it is still remained difficult to find a quantitative relationship between the final states of vulcanized rubber and initial formulation or processing conditions. Dynamic differential scanning calorimetry (DSC) method is known as a comparatively easy method to research for the rubber vulcanization in both experimental and analysis. In the present research, a study on the vulcanization reaction of NR/CB composites modified by isoprene(IR) and chloroprene(CR) rubbers is carried out using dynamic DSC method. Thermograms with several different heating rates were obtained and analyzed using the Kissinger method. Analysis showed that the vulcanization reaction was progressed through the first order reaction mechanism. In addition, the reaction temperature was severely influenced by the kinds or rubber modifiers, in this case, more influenced by CR than by IR. Those effects were clearly verified in the values of activation energy. Kinds of carbon blacks, however, could hardly influence on the reaction mechanism.

• Clean Technology
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• v.12 no.4
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• pp.198-204
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• 2006

The modification of biodegradable polycaprolactone was accomplished by reactive extrusion with various contents of free radical initiator. Reaction conditions were in the temperature range of $130^{\circ}C$ to $180^{\circ}C$ with initiator contents of 0.1, 0.3, 0.5 and 1.0 wt%. To characterize the modified polycaprolactone (PCL), molecular weight was measured by gel permeation chromatography(GPC) and thermal, mechanical and rheological properties as well as biodegradability were measured. The modified PCL (MPCL) with 1% of initiator showed ca. 20% increase in crystallinity and ca. 50% increase in tensile modulus. Also, a large increase in rheological properties such as complex viscosity, storage and loss modulus was observed. The biodegradability of most MPCL was higher than that of virgin PCL.

• Journal of the Korean GEO-environmental Society
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• v.13 no.6
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• pp.41-50
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• 2012

In general, it is critical that grout consistency permit the complete filling of void space without segregation of ingredients. Recently, the antiwashout agent is used on underwater grout materials for preventing the grout from the segregation in water. This study introduces a new type of antiwashout underwater and flowable grout material using viscous modifiers and its characteristics comparing with conventional grout materials in fresh and sea water. It is found that the antiwashout underwater grout both in fresh and sea water has enough strength and good resistance to segregation.

• Korean Chemical Engineering Research
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• v.53 no.5
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• pp.584-589
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• 2015

For effective power generation with fuel cells in low-oxygen environments such as submarines and unmanned underwater vehicles, a hydrogen source which has a high hydrogen storage density is required. Diesel fuel is easy to storage and supply due to its liquid phase and it has a high density per unit volume and unit mass of hydrogen that required for driving the fuel cells. In this paper, diesel fuel was selected as a hydrogen source for driving the fuel cell in oxygen lean environments. In addition, the aqueous hydrogen peroxide solution was suggested as an alternative oxidant for hydrogen production through the diesel reforming reaction because of its high oxygen density and liquid phase which makes it easy to storage. In order to determine the characteristics of hydrogen peroxide as an oxidant of diesel reforming, comparative experiments were conducted and it was found that hydrogen peroxide solution has the same characteristics when reformed with oxidants of both steam and oxygen. Moreover, the commercial diesel reforming performances were analyzed according to the reaction temperature and concentration of aqueous hydrogen peroxide solution. Then, through the 49 hours accelerated degradation tests, the possibility of hydrogen production via diesel and aqueous hydrogen peroxide solution was confirmed.

• Journal of the Korea Concrete Institute
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• v.14 no.3
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• pp.299-306
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• 2002

The purpose of this research was to develop a rapid setting cement latex modified concrete (RSLMC) for bridge deck repairing and overlaying. The main experimental variables were latex contents, antifoamer contents and water-cement ratioes. The workability, strength development and permeability were measured as responses. The results showed that latex content increased the slump and reduced the unit water required for same workability. The air contents were measured as 8.0∼9.0％ and 2.0∼3.0％ without antifoamer and with 1.6∼3.2％ of antifoamer, respectively. This resulted in the increment of compressive strength development by 10∼20 ％. The flexural strength of RSLMC increased greatly as the latex content increased, but not in compressive strength. The compressive strength and flexural strength developed enough for opening the overlayed RSLMC to the traffic after 3 hours of RSLMC placement. The permeability of RSLMC was evaluated as negligible due to its very low charge passed. Thus, RSLMC could be used at repairing or overlaying the concrete bridge deck at fast-track job sites.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.111-120
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• 2010

This study evaluated strength properties of recycled asphalt concretes using warm-mix technology. Granite with maximum size of 13mm and penetration grade of 80-100 virgin binder were used for mixing in recycled mixtures. Mix design was performed using 20% and 30% RAP(coarse : fine= 6 : 4) contents. GPC, penetration, absolute viscosity and kinematic viscosity were measured for determining ratio of two warm-mix additives (Evotherm and Sasobit). Low-density polyethylene(LD) used as asphalt modifier for improving stiffness of recycled WMA mixtures in this study. Therefore, a total of 11 mixtures were prepared in this study; 8 warm-mix recycled mixtures(2 RAP contents${\times}$2 warm-mix additives${\times}$2 modifiers), 2 hot-mix recycled mixtures and 1 HMA virgin mixture(control). Deformation strength, indirect tensile strength, moisture sensitivity, permanent deformation by wheel tracking tests were measured out for evaluating fundamental properties of recycled asphalt concretes using warm-mix technology.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.507-512
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• 1996

저준위 방사성 폐액의 전처리공정으로써 한외여과막의 적용성을 평가하기 위해서 폐액내에 있는 오일과 계면활성제의 상호작용을 규명하고 오일에멀젼 용액의 fouling정도를 조사하였다. 막의 fouling을 감소시키는 한 방법으로 계면활성제에 의해 막의 표면을 개질하므로서 막투과 flux는 크게 증가되는 효과를 얻었다. 친수성막과 소수성막에 대하여 몇가지 계면활성제로 처리한 후 성능을 비교한 결과 소수성인 폴리솔푼막에 대한 SDS의 표면개질이 가장 유리하였다. 표면처리 막의 적용성을 평가한 결과 미량의 계면활성제나 염이 포함된 오일에멀젼 용액에 대해서는 매우 우수한 투과 성능을 얻을 수 있으나 CMC 이상의 계면활성제가 포함된 오일용액에 대해서는 처리가 불가능하였다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.389-390
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• 2000

최근 지구 온난화의 55% 이상을 차지하고 있는 이산화탄소를 유용한 화합물로 전환하고자 메탄을 환원제로 사용한 이산화탄소 개질반응으로부터 합성가스 생성에 관한 연구가 활발히 진행되고 있다. 메탄의 이산화탄소 개질반응은 수증기 개질반응보다 낮은 합성 가스비의 생성, 온실효과를 유발하는 이산화탄소의 저감, 반응의 높은 흡열도를 이용한 화학에너지 전송 시스템의 응용 면에서 그 의의가 있다. (중략)

• Textile Coloration and Finishing
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• v.7 no.4
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• pp.105-112
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• 1995

방전에 의한 섬유의 표면개질 기술로서, 저온 플라즈마, Sputter Etching 처리에 대해 서술하고 표면개질 효과를 표면장력, ESCA, SEM을 근거로해서 고찰하였다. 더우기 접착성, 염색물의 색채에 미치는 효과에 대해 검토하였다. 섬유의 염색가공에 있어 젖음, 발수, 발유, 접착, 대전방지, 광택, 촉감 등의 표면에 관련하는 기능적 혹은 감각적 특성이 중요한 역할을 하고 있다. 섬유재료의 내부(bulk)의 특성을 살리면서 표면특성의 개질에 의해 한층 기능성을 향상시키는 것은 큰 의미를 가지며, 그와 관련한 표면개질 기술의 연구에 관심을 갖게 되었다. 종래에는 오로지 습식법에 의한 화학약품 처리나 그라프트 공중합 등이 많이 이용되어져 왔으나 습식가공법은 공업적으로는, 다량의 물, 유기용제, 색재, 수지, 계면활성제 등을 사용하기 때문에 피처리물의 건조에 필요한 에너지, 배수처리, 유기용제의 회수 등의 문제가 지적되고 있다. 이들 습식계의 문제점을 극복하는 기술로서 최근은 방전처리나 자외선 처리 등의 건식처리가 많이 연구되어 오고 있다.