• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2011년도 후기공동학술대회 논문집
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• pp.88-89
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• 2011

The study on synthesis of carbon nanomaterials by H2 mixing in counterflow methane diffusion flames has been experimentally conducted. We have also investigated on effect of catalyst and temperature in flame. The counterflow flame was formed by many kind of gas (fuel side using $CH_4-H_2-N_2$ and oxidizer side $N_2-O_2$) and nitrogen shields discharge on each other side to cut off oxidizer of the atmosphere. Ferrocene was used as a metal catalyst for CNTs synthesis. substrate was used to deposit carbon nanomaterials and these were analyzed by FE-SEM. We could find that carbon nanotubes and many kind of carbon nano materials were formed in Cu wire substrate, through this experiment.

• 마이크로전자및패키징학회지
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• 제17권1호
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• pp.75-80
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• 2010

다공성 탄소전극기지 위의 무전해 니켈도금에 관한 연구를 하였다. 다공성 탄소전극기지로는 다공도가 20 ${\mu}m$ 이상인 것과 16~20 ${\mu}m$ 인 것을 사용하였다. 소수성인 탄소 표면은 $60^{\circ}C$ 이상의 암모니아 용액에 침적함으로써 그 표면 성질이 친수성으로 변화 되었고, 40분 이상 침적 시 접촉각이 $20^{\circ}$ 이하까지 측정 되었다. 도금욕의 pH가 증가됨에 따라 탄소기지 위에 도금된 니켈 도금층의 인의 석출량은 감소하였으며 니켈 도금층이 결정질 구조를 갖는 현상이 관찰되었다. 도금층의 두께는 pH가 증가함에 따라 증가하였다. 활성화 처리를 위한 $PdCl_2$의 농도에 따른 도금층의 두께 변화는 없었으나, 도금에 필요한 $PdCl_2$의 최소농도는 5 ppm 이상인 것으로 나타났다.

• Carbon letters
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• 제11권3호
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• pp.184-191
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• 2010

Carbon nanotubes are unique tubular structures of nanometer diameter and large length/diameter ratio. The nanotubes may consist of one up to tens and hundreds of concentric shells of carbons with adjacent shells separation of ~0.34 nm. Multiwalled carbon nanotubes were synthesized by arc-discharge technique. MWCNTs were formed at the cathode deposit along with other carbonaceous materials like amorphous carbon, graphite etc. However, to get the best advantage of carbon nanotubes in various advanced applications, these undesired carbonaceous materials to be removed which is a challenging task. In the present study, various techniques were tried out for purifying MWCNTs such as physical filtration, chemical treatment and thermal annealing. SEM, FTIR, TGA and BET techniques were used to characterize the CNTs at various stages. Results shows that suitable chemical treatment followed by thermal annealing under controlled flow of oxygen gives the better route for purification of carbon nanotubes.

• 한국정밀공학회지
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• 제23권12호
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• pp.122-127
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• 2006

This paper reports on the development of carbon nanotube tip modified with focused ion beam(FIB). We used an electric field which causes dielectrophoresis, to align and deposit CNTs on a metal-coated canning Probe Microscope (SPM) tip. Using the CNT attached SPM tip, we have obtained an enhanced resolution and wear property compared to that from the bare silicon tip through the scanning of the surface of the bio materials. The carbon nanotube tip was aligned toward the source of the ion beam allowing their orientation to be changed at precise angles. By this technique, metal coated carbon nanotube tips that are several micrometer in length are prepared for SPM.

• 한국환경과학회지
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• 제17권11호
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• pp.1235-1241
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• 2008

Membrane separation is extensively used for water/wastewater treatment because of its efficiency separation processes. However, particles in the feed water can deposit and accumulate on the membrane surface to created cake layer. As a consequence, the selectivity of the membrane and flux through the membrane are decreased, which is called fouling/blocking phenomenon. In order to solve fouling problem, we developed a novel membrane named Carbon Whisker Membrane (CWM) which contains vapor-grown carbon fibers/whiskers on the surface of the membrane and a layer of carbon film coated on the ceramic substrate. We firstly employed polymethyl methacrylate (PMMA) as a testing material to investigate the fouling mechanism. The results suggested that Carbon Whiskers on the surface of the membrane can prevent the directly contact between the membrane body and particles so that the fouling/blocking could not occurred easily compared to the membrane without carbon whiskers. We also researched the relationship with the diameter, density of carbon whisker on the membrane surface and total flux of solutions. Finally, we will be able to control the diameter and density of carbon whiskers on the membrane and existence of carbon whiskers on the membrane, it is important factor, might be prevent fouling/blocking in the water treatment.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.188-191
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• 2008

There have been many methods for producing natural gas from gas hydrate reservoirs in permafrost and sea floor sediments. It is well knownthat the depressurization should be a best option for Class 1 gas hydrate deposit, which is composed of tow layers: hydrate bearing layer and an underlying free gas. However many of gas hydrate reservoirs in sea floor sediments are classified as Class 2 that is composed of gas hydrate layer and mobile water, and Class 3 that is a single gas hydrate layer. The most appropriate production methods among the present methods such as thermal stimulation, inhibitor injection, and controlled oxidation are still under development with considering the gas hydrate reservoir characteristics. In East Sea of Korea, it is presumed that the thick fractured shale deposits could be Class 2 or 3, which is similar to the gas hydrate discovered offshore India. Therefore it is needed to evaluate the possible production methods for economic production of natural gas from gas hydrate reservoir. Here we would like to present the production of natural gas from gas hydrate deposit in East Sea with industrial flue gases from steel company, refineries, and other sources. The existing industrial complex in Gyeongbuk province is not far from gas hydrate reservoir of East Sea, thus the carbon dioxide in flue gas could be used to replace methane in gas hydrate. This approach is attractive due to the suggestion of natural gas productionby use of industrial flue gas, which contribute to the reduction of carbon dioxide emission in industrial complex. As a feasibility study, we did the NMR experiments to study the replacement reaction of carbon dioxide with methane in gas hydrate cages. The in-situ NMR measurement suggeststhat 42% of methane in hydrate cages have been replaced by carbon dioxide and nitrogen in preliminary test. Further studies are presented to evaluate the replacement ratio of methane hydrate at corresponding flue gas concentration.

• 오토저널
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• 제10권5호
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• pp.61-68
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• 1988

This paper reports the basic performance of a naturally aspirated DI diesel engine which is used widely in industry and agriculture when vegetable oils are used as fuel substitutes. In this paper, the properties of vegetable oils as diesel fuel were investigated and the load-performance of diesel engine when vegetable oils were used, as tested compared against diesel fuel. The general objective of this investigation is to realize an efficient, clean, and low carbon deposit combustion of the vegetable oils in diesel engines, showing their feasibility as diesel fuel substitutes. The results of this experiment were as follows; (1) Compared with diesel fuel, the droplet size of vegetable oil is very large. (2) Compared with diesel fuel, rapeseed oil, palm oil, and their blend fuels offered lower smoke, lower NOx, ower engine noise, and high thermal efficiency in a D.I. diesel engine However, there were carbon deposit and piston ring sticking problems with long-term operation. (3) For ethanol-rapeseed oil blends, a 10-20% of ethanol content is recommended to enable lower BSHC and less smoke without a remarkable increase in engine noise compared with pure rapeseed oil. (4) A 10% oxygen content in the vegetable oils is contributed to reduced smoke emission.

• 방사성폐기물학회지
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• 제5권1호
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• pp.1-7
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• 2007

흑연음극을 이용하여 LiCl-KCl공융염내에서 금속우라늄의 전해정련을 수행하였다. Uraniurn-Graphite Intercalation Compound(U-GIC)의 형성에 의하여 우라늄 전착물의 sell-scraping이 일어나며 전해정련에서 stripping과정을 생략함으로서 전해효율을 높일 수 있다. 우라늄 전착물내의 희토류 원소 오염은 무시할 만 하였으나 약 300ppm정도의 탄소가 오염되어 있는 것으로 관찰되었다. 탄소 오염은 이트륨을 이용한 정제공정 등을 거칠 경우 제거 가능하리라 사료된다. 회수된 우라늄 전착물의 조직 특성을 분석하였으며, 스틸 음극에 의해 회수된 전착물과 비교하였다. 이 결과는 초기 실험결과 이며 보다 심층적 연구를 통하여 사용 후 금속핵연료의 전해정련 개념을 개선시킬 수 있을 것으로 판단된다.

• 자원환경지질
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• 제38권4호
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• pp.421-434
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• 2005

미국 네바다주의 칼린형 금광상을 모델로 강원도 예미지역에 대한 칼린형 금광상의 잠재력을 평가하였다 연구지역에 분포하는 고생대 퇴적암은 스러스트 단층 및 습곡으로 구성된 뚜렷한 구조적 규제를 받았으며, 고각의 단층과 투수성이 큰 예미각력암 및 호층의 석회질 이암층이 결합되어 있다. 남부 지역에 분포하는 석회암에 대한 탈륨, 안티몬, 비소, 은, 납, 아연, 구리, 몰리브덴 및 텅스텐에 대한 원소부화도의 분포 양상은 칼린형 금광상과 지구화학적 유사성을 나타낸다. 또한, 탄소와 산소동위원소 값은 이들 지역이 광역적으로 열수의 영향을 받았음을 지시한다. 연구지역에 대한 지질구조, 화학분석, 변질광물 감정 및 안정 동위원소 분석 및 지구물리학적 해석 견과, 광화대는 북동부 방향으로 연장될 가능성이 높으며 이를 확인하기 위해서 앞으로 체계적인 정밀탐사가 필요하다.

• 한국토양비료학회지
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• 제27권4호
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• pp.315-320
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• 1994

This survey report introduced briefly peat deposits in SAKHALIN island of eastern SIBERIA continent. Peat industry was promoted as leading resources for development in this island by national control economic plan of central government before CIS. But development of deposit was left suspension of operation due to investment now. In southern area, about 10km from Yuzunosakhalinsk, two deposits of peat field were explored. One of them (Troisk) was suspended at begining stage of peat harvest from 300ha field and the other(Missilop) was producing the compact peat through drying and pulverizing from 350ha peat field which showed long run harvest activities. There are plenty of peat deposits near the Polonai Reika (river) in the central area of this island, At Zbaikaritz, 40km nothern area from Polonaisk, 135ha of peat field was developed. This field was left without working but established field preparation and could be able to be harvested any time if machines and utlities were settled. At southern suburb 10km from Polonaisk, about 40ha field of virgin deposit has been established planning for development. The plan involved estimated amount of peat, deposit depth, water level, drainage and leading road. The most of peat deposits accumulated from sphagnum moss. Texture is coarse but it contains more than 95% of organic carbon near to 0.5% of total nitrogen and acidity showed pH4-5.