• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.4
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• pp.82-88
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• 2012

The usage of recycling agent is the most effective way of enhancing the performance of recycled asphalt pavement. Generally, many countries accepted these recycling agents retarding the various types of cracks resulted in binder aging. Contrary to such general tendency, recycling agents are used as very small amount in domestic recycling plant. The main reason of this is relatively high price of recycling agent. Even though agent price is high, agent can be a effective and economical way of alternative in asphalt recycling. In this study, penetration and softning point test performed by using RTFO(Rolling Thin Film Oven) aged binder. And, PG(Performance Grade) at high temperature, fatigue and MSCR(Multi Stress Creep and Recovery) tests exercised. The oil type agent is worked well to retrieving target penetration number. In PG test, $G^*/sin{\delta}$ of agents identically showed high value and polymer type agent is good at recovery value.

• 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.

• Journal of Energy Engineering
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• v.7 no.1
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• pp.24-34
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• 1998

In this research, effects of the types and amounts of binders and additives on desulfurization and regeneration reactivities of zinc titanate were investigated. Bentonite and kaolinite were used as binders and Mo-based, Ni-based, and Cu-based compounds were used as additives. A thermogravimetric analyzer (TGA) was utilized to investigate reactivities of desulfurization and regeneration for each sorbent. Two-cycle reactions of desulfurization-regeneration were performed in the TGA reactor. Results of XRD analysis showed that all sorbents had the crystalline phases of $Zn_2TiO_2$ and $Zn_2Ti_3O_8$ irrespective of the type and amount of binder and additive. Kaolinite-bound sorbents gave higher surface areas than bentonite-bound ones and the surface areas and pore volumes of sorbents increased with amount of binder increased. It was found that the most suitable temperatures for desulfurization and regeneration were 680$^{\circ}$C and 730$^{\circ}$C, respectively, and the sorbent prepared by the addition of 3 mol% CuO showed the best performance in terms of desulfurization and regeneration. Nio-added sorbents had good regenerability whereas $MoO_3-based$ sorbents showed poor performance. In cycle experiments in a fixed bed reactor 3 mol% CuO-added sorbents showed high reactivity.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.178.2-178.2
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• 2011

바이오디젤이란 식물성 기름, 동물성 지방, 폐식용유 등의 재생 가능한 자원을 촉매 존재 하에 알코올과 반응시켜 생성되는 에스테르 혼합물을 말하며 경유와 물성이 유사하므로 경유에 혼합하여 압축착화 방식인 디젤엔진에 사용할 수 있다. 그러나 바이오디젤은 경유에 비하여 탄소-탄소 간 이중결합을 가지고 있는 성분을 많이 함유하고 있기 때문에 공기에 의해 산화가 일어나기 쉽다. 일반적으로 폐놀계 향산화제인 t-buthylhydroquinone(TBHQ)를 사용하여 산화안정성을 향상시키나 국내에서 사용되는 산화방지제는 전량 수입에 의존하고 있어 제품 개발에 의한 국산화가 시급한 실정이다. 본 연구에서는 폐유지로부터 생산한 바이오디젤의 산화안정성 향상을 위하여 폐놀 및 아민계 등의 산화방지제를 합성하여 바이오디젤에 적용하였으며, 다양한 물성시험방법을 적용하여 석유 및 석유대체연료 사업법에서 규정하는 바이오디젤의 품질기준을 확인하였다. 또한 EN 14112 바이오디젤 산화안정성 시험방법으로 폐놀 및 아민계 등의 산화안정성을 확인하였다. 본 연구는 산학연 공동기술개발 1차년도 사업으로 한국화학연구원과 공동으로 수행하였으며, 산화방지제 적용평가를 통해 우수한 제품을 선정하여 2차년도에는 차량 테스트를 통해 연료 첨가제로서의 적합성을 검증할 예정이다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.110.1-110.1
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• 2011

최근 식물성 기름으로부터 생산된 바이오디젤의 보급이 활발해지면서, 그 원료의 안정적 확보에 대한 어려움과 원료가격 상승의 문제점이 발생하고 있다. 이러한 문제점을 극복하기 위한 대안으로 다양한 종류의 기름이 검토되고 있으며, 그 중 하나가 축산 폐유지를 이용한 바이오디젤의 생산이다. 그러나 축산 폐유지로부터 생산된 바이오디젤은 저온유동성이 열악하여 개선이 필요하다. 축산 폐유지 바이오디젤의 저온필터막힘점은 $6{\sim}8^{\circ}C$로 국내 동절기 품질 기준 $0^{\circ}C$ 이하를 만족하지 못한다. 본 연구에서는 축산 폐유지로부터 생산된 바이오디젤의 열악한 저온특성을 개선하기 위해 저온필터막힘점 개선 첨가제 6종을 사용하여 각각의 첨가제 혼합에 의한 저온유동성 개선 효과를 분석하였다. 각각의 첨가제를 1,000 ~ 5,000ppm 범위에서 폐돈지 및 폐우지 바이오디젤에 첨가하였다. 그 결과, Wintron을 제외한 나머지 첨가제는 폐돈지 바이오디젤의 저온필터막힘점을 최저 $0^{\circ}C$까지 개선할 수 있었다. 하지만 폐우지 바이오디젤의 경우, 첨가제에 의한 저온유동성 개선의 효과는 매우 적었다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.386-388
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• 2009

차세대 에너지로 연료전지가 각광을 받고 있는 현재, 세계 각국에서는 연료전지의 상용화를 위해 노력하고 있다. 그러나 촉매분야에서 백금계 촉매의 사용량의 문제에 따른 매장량 한계점과 귀금속이라는 문제점이 존재하기 때문에 이에 대하여 대책강구가 필요한 시점이다. 이에 백금 촉매의 활성을 증대하고자 나노 크기의 제어 연구가 진행되고 있다. 또한, 촉매의 구조적인 면에 따라 촉매의 활성이 달라지는 점을 착안하여 백금계의 나노 형상 조절 연구와 백금계 촉매를 대체할 비백금계의 촉매 개발 연구가 활발히 진행되어지고 있다. 이에 본 연구는 백금계 촉매 중 Pd을 polyol process에 의한 나노 형상 조절을 통하여 단위 질량당(or 단위 부피당) 촉매의 활성을 높이고자 하였다. Polyol process에서는 환원제, 계면활성제, 온도, 시간, 기타 첨가제에 따라 나노 형상이 다르게 조절되는데, 이에 계면활성제로 PVP를 사용하고, 반응속도 및 형상조절을 위해 다양한 첨가제를 이용하여 polygonal Pd NPs을 형성하였다. 본 나노 형상 조절에서는 첨가제와 온도가 가장 큰 영향을 미치는 요인으로 착안하여 그에 따른 polygoanl Pd NPs의 사이즈 조절을 통해 전기화학 특성이 차이의 연구에 중점을 두었다. 이에 따라 나노 형상 조절이 된 Pd촉매를 이용하여 상용화된 촉매(Pd/C(XC-72R))에 비하여 전기화학적인 특성의 차이와 Pd 촉매의 촉매적 특성의 효과를 보고자 한다.

• Korean Journal of Plant Tissue Culture
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• v.25 no.5
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• pp.347-351
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• 1998

Plant regeneration via organogenesis from leaf and stipule explants of micropropagated shoots of strawberry (Fragaria $\times$ ananassa cv. Suhong) was achieved. Leaf and stipule explants were detached from shoot-tip cultured shoots and cultured on MS medium with various combinations of BA and NAA under light or dark condition. Shoot regeneration from leaf explant was observed after 3 weeks in culture and was good at the high ratio of BA and NAA among various combination treatments. The highest shoot regeneration frequency from leaf explants was obtained with 1.0 mg/L BA and 0.1 mg/L NAA, in which 31.1% shoot regeneration frequency(1.7 shoots per leaf explant) was yielded. In case of stipule explants, shoot regeneration was largely affected by plant growth regulators during incubation under dark condition for initial 4 weeks but not under continuous light condition. The combination treatment with 2.0 mg/L BA and 0.1 mg/L NAA showed the most excellent shoot regeneration from stipule explants, where 44.4% regeneration frequency(4.0 shoots per explants) obtained. Regenerated shoots were rooted on MS medium with 0.1 mg/L NAA after shoot elongation, and the plantlets regenerated were transferred to soil mixtures with vermiculite and perlite for acclimation.

• Journal of the Korean GEO-environmental Society
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• v.13 no.2
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• pp.67-73
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• 2012

Asphalt pavement waste can be recycled by crushing and heating methods with additional virgin materials and additives. In this study, a new additive using Sasol wax and Polyolefin elastomer was used for improving the quality of the Superior recycled asphalt pavement(SRP). Additive was added into the recycled mixture by 1.5% and 3% of binder content in order to have PG 70-22 and PG 76-22. Both mixtures were tested by Marshall apparatus, indirect strength testing methods, toughness testing methods, moisture susceptibility testing methods and wheel tracking testing methods. Test results met the standards of KS F 2349 and GR F 4005. Through research, it was found that these special recycled mixtures could be applied for the surface and base course of heavy traffic roads or equivalents. About 13,000 tons of the recycled mixture has been applied on Seoul Olympic road to provide new road to Hangang park for Seoul citizens.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.802-806
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• 2001

Diesel particulate trap is the most reliable system to reduce the particulate matters from diesel engine. Filter is the core component of DPF and ceramic monolith type is dominantly used, which is expensive and fragile relatively at thermal shock. Porous metal filter, which has superior thermal characteristics and low cost, was tested in order to analyze the regeneration performance by using with ferrocene additive. This filter showed the 72% filtration efficiency, additives itself diminished 48% of PM from engine out emission, and final PM reduction ratio of 89% was achieved by DPF system with D-13 test mode.

• Microbiology and Biotechnology Letters
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• v.13 no.3
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• pp.311-314
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• 1985

Ganodema lucidum protoplasts were formed by the treatment of Novozym 234. The osmotic stabilizers such as mannitol were effective enough to produce protoplasts up to 10$^{6}$ $m\ell$. For regeneration, however, MgSO$_4$.7$H_2O$ was suitable. When inositol and sucrose were employed as osmotic stablizers, the regeneration ratio reached to 0.26％. Overlay of Streptomycin sulfate added agar was required to prevent bacterial contamination.