• Current Optics and Photonics
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• 제1권1호
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• pp.7-11
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• 2017

In this study, multilayered graphene was easily transferred to the target substrate in one step using thermal release tape. The transmittance of the transferred graphene according to the number of layers was measured using a spectrophotometer. The sheet resistance was measured using a four-point probe system. Graphene formed using this transfer method showed almost the same electrical and optical properties as that formed using the conventional poly (methyl methacrylate) transfer method. This method is suitable for the mass production of graphene because of the short process time and easy large-area transfer. In addition, multilayered graphene can be transferred on various substrates without wetting problem using the one-step dry transfer method. In this work, this easy transfer method was used for dielectric substrates such as glass, paper and polyethylene terephthalate, and a sheet resistance of ~240 ohm/sq was obtained with three-layer graphene. By fabricating organic solar cells, we verified the feasibility of using this method for optoelectronic devices.

• 한국재료학회지
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• 제3권4호
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• pp.403-409
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• 1993

본 논문에서는 Si(111)에 대한 건식산화와 어닐링에서 결함의 억제 또는 제거에 $NH_3$가 효과적임을 밝혔다. 산화방식은 건식산화(dry $O_2$ oxidation)및 $NH_3$산화($NH_3$ added in dry $O_2$oxidation)를 택하였고 $N_2$및 $NH_3N_2$분위기에서 어닐링 효과를 평가하였다. 건식산화에서는 발생되는 결함이 성장시간에 따라서 길이가 길어지며, $NH_3$산화에서는 결함이 발견되지 않았다. 또한 초기산화를 $NH_3$산화로 하고서 건식산화를 하였을 때 계면에서의 결함을 제거하는 효과가 있다. 건식산화 또는 $NH_3$산화를 한 후 이들 시료에 대하여 7.5% $NH_3N_2$분위로 어닐링하면OSF의 게터링(gettering)효과가 있었다. $NH_3$산화방식에서 7.5%$NH_3N_3$분위기로 어닐링했을때가 건식산화방식에 비하여 OSF의 길이가 20%정도 감소하였다. OSF의 모양은 pit형으로 (111)면에 대하여 (011)면 쪽으로 게터링이 일어났으며<110>방향으로 식각되는 성질이 있었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권2호
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• pp.135-138
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• 2004

In order to find potential anticancer agents, we extracted pheophytin from silkworm feces according to various dry and storage methods such as sun dry, shade dry, fresh freezing dry and freezing dry after freezing storage (for 1∼3 years). The pheophytin extracts, mainly 10-hydroxypheophytin a, little b, of various storage silkworm feces were analyzed by reversed-phase high-performance liquid chromatography with photodiode array and fluorescence detection. The content of those pheophytih in old silkworm for 3 years (freezing storage and freezing dried in use, or freezing dried and cold storage) was better than others. The cytotoxicity of the pheophytin extracts and ethanol extracts of various storage silkworm feces were measured using Jurkat cells originated from human leukemia, using dye uptake assay (MTT) in order to find effective photodynamic therapeutic agents. The anticancer activity of those pheophytin extracts in various storage methods showed little difference among them. But ethanol extracts of fresh freezing dried silkworm in the current year was good cytotoxic activity than those of any other silkworm feces. With regards to these results, fresh ethanol extracts of silkworm feces were better than old ones. On the other hands, the pheophytin extracts of old silkworm feces contained the highest percentage of pheophytin content and showed good cytotoxicity against cancer cells by changing the pheophytin into pheophobide in the degradative process.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.953-956
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• 2008

국내 초고층 프로젝트의 증가에 따라 필연적으로 고강도 콘크리트의 사용이 증가되고 있다. 콘크리트의 강도가 증가됨에 따라 화재시 단면결손을 유발하는 폭렬의 경향성이 커지고, 콘크리트부재 내부의 온도를 현저하게 증가시키며 심각한 구조적 손상을 유발할 수 있다는 문제점이 대두되었고, 정부에서도 2008년 7월부터 고강도 콘크리트의 내화성능 관리기준을 시행하고 있다. 이에 국내 각 건설사들은50MPa 이상의 고강도 콘크리트에 대하여 폭렬방지 대책을 수립 중에 있다. 본 연구소에서는 신축공사 및 리모델링공사에도 적용이 가능한 고강도 콘크리트 폭렬방지 공법인 PFB (Posco E&C Fire Board) 공법을 개발하여 지속적인 공법 개선에 노력하고 있다. 본 연구는 고강도 콘크리트 폭렬방지 대책으로 개발한 PFB 공법 개발에 대한 일반사항, 현재 건식화 공법 개발 및 당사 PJT적용 현황에 대한 내용을 기술하고자 한다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.92-93
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• 2014

This study was carried out to process the shape of dry bottom ash using the impact crusher and gravity crusher, which are identified as most effective in improving grain shape through the preceding research, and a comparison was made between concrete that utilized the processed dry bottom ash as aggregate and concrete containing dry bottom ash before processing to understand properties of the new concrete.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.865-870
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• 2000

The flow and the moisture contamination of the dry room in the manufacturing process of lithium ion battery are analyzed numerically by finite volume method. Standard ${\kappa}-{\varepsilon}$ turbulent model widely applied in predicting turbulent flow is adopted in this study. Moisture contamination and distribution are studied by assumption of two cases; one-point generation and uniform generation throughout the room. To evaluate ventilation efficiency on moisture contamination, scales of ventilation efficiency are introduced. From these analyses, moisture contamination is strongly dependent on the flow field and the radius of moisture contamination can be reduced by closing a part of outlets in a dry room.

• 한국공작기계학회논문집
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• 제13권2호
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• pp.127-132
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• 2004

In industrially advanced countries, environmentally conscious machining was eagerly studied because of ecological and economical reasons. As the environmental regulations become stricter, the new machining technologies which take environmental aspects into consideration are being developed. Recently the research institutions have established application method for dry, semi-dry, oil-mist and compressed cold air machining. In this paper the performance of new compressed cold air system for environmentally conscious machining is investigated and machinability of dry and new compressed cold air machining is evaluated. A series of tests are carried out by using measuring equipments in condition of dry and compressed cold air machining.

• 한국염색가공학회지
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• 제2권3호
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• pp.43-50
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• 1990

The purpose of this paper is to investigate the dyes solubility of dry cleaning solvents among the current domestic products. The dyes were experimented in following way; 1) The flow rate of dyes by paper chromatography method. 2) The color difference & the absorbance of solvents between the dyed fabrics before and after dry cleaning. From the experiment, following results were obtained. 1. In paper chromatography methods, the flow rate of dyes in the disperse dyes was bigger while flow was not shown in the direct dyes & acid dyes. 2. The more the number of times on dry cleaning in dyed fabrics was, the higher the absorbance of solvents was shown. The results were showed following order, PerchloroethyleneHydrocarbon> Fluorocabon. 3. The color difference between before & after dry cleaning on dyed fabrics showed bigger in disperse dyes.

• 방사성폐기물학회지
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• 제19권2호
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• pp.205-214
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• 2021

Currently, the interim storage pools of spent fuels in South Korea are expected to become saturated from 2024. It is required to prepare an operation plan of a domestic dry storage facility during a long-term period, with the researches on safety evaluation methods. This study modified the FRAPCON code to predict the spent fuel integrity evaluation such as the axial cladding temperature, the hoop stress and hydrogen distribution in dry storage. The cladding temperature in dry storage was calculated using the COBRA-SFS code with the burnup information which was calculated using the FRAPCON code. The hoop stress was calculated using the ideal gas equation with spent fuel information such as rod internal pressure. Numerical analysis method was used to calculate the degree of hydrogen diffusion according to the hydrogen concentration and temperature distribution during a dry storage period. Before 50 years of dry storage, the cladding temperature and hoop stress decreased rapidly. However, after 50 years, they decreased gradually and the cladding temperature was below 400 K. The initial temperature distribution and hydrogen concentration showed a parabolic line, but hydrogen was transferred by the hydrogen concentration and temperature gradient over time.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.826-828
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• 2003

With a new PDP transparent dielectric layer formation technique, we were able to make dielectric layer with high transmittance by using dry film type dielectric material. We optimized dielectric pastes for dry film and they showed good process properties in lamination , drying and firing.