• E2M - 전기 전자와 첨단 소재
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• 제9권3호
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• pp.240-245
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• 1996

Non-ozone layer destructive Chlorofluorocarbon(CFC) altematives(CHCIF$_{2}$ and $C_{2}$H$_{2}$F$_{4}$) have been initially used for laser-induced thenrmochemical etching of GaAs. High etching rate up to 188.mu.m/sec and an aspect ratio of 2.7 have been achieved by a single scan of laser beam, respectively. The etching rate at constant ambient gas pressure was found to saturate for beam power. The chemical compositions of the reaction products deposited on the etched groove were measured by Auger electron microscopy(AES). Etched profile, depth and width were observed by scanning electron microscope(SEM).

• BMB Reports
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• 제30권5호
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• pp.315-319
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• 1997

It was discovered that monoclonal anti-erythropoietin (EPO) antibody CFC-6 can neutralize EPO-induced cell activation. To know the binding site of CFC-6, recombinant human erythropoietin (rhEPO) was digested with Glu-C, followed by a separation using high performance liquid chromato graphy (HPLC). Each HPLC fraction was blotted on the nitrocellulose membrane and the membrane was treated with anti-EPO antibody CFC-6 and anti-mouse antibody which is modified with peroxidase. Only one spot showed the color and the fraction was sequenced by Edman degradation. The results suggest that CFC-6 recognizes amino acid sequence V63-W-Q-G-L-A-L-L-S-E72 which is a part of helix II of the EPO molecule. Binding of CFC-6 to EPO may inhibit EPO binding to its receptor, which implies that the antibody binding site and the receptor binding site are close or overlapping.

• 대한기계학회논문집
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• 제19권9호
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• pp.2316-2327
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• 1995

Experimental results from nucleate pool boiling heat transfer with various finned tubes in CFC11, HCF123 and HCFC141b are reported. One plain tube and four low fin tubes of various fin densities were tested in an attempt to find out the optimum fin density in the heat flux range of 10-60 kW/m$^{[-992]}$ at near atmospheric pressure. The results indicated that CFC11 showed the highest heat transfer coefficients. Its alternatives, HCFC123 and HCFC141b, showed 3-5% lower heat transfer coefficients than those of CFC11 at the same heat flux. As the fin density increases, so does the heat transfer surface area. Measured heat transfer coefficients, however, do not necessarily always increase as the fin density increases. This unique phenomenon seems to be caused by the coalescence of the bubblers that prevent the cool liquid from entering into the fin valleys. For all the refrigerants tested, the optimum fin density yielding the highest performance was 28 fins per inch confirming the previous results by other researchers.

• Journal of Power Electronics
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• 제16권5호
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• pp.1743-1751
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• 2016

The increasing demand for high voltage DC grids resulting from the continuous installation of offshore wind farms in the North Sea has led to the concept of multi-terminal direct current (MTDC) grids, which face some challenges. Power (current) flow control is a challenge that must be addressed to realize a reliable operation of MTDC grids. This paper presents a reduced switch count topology of a current flow controller (CFC) for power flow and current limiting applications in MTDC grids. A simple control system based on hysteresis band current control is proposed for the CFC. The theory of operation and control of the CFC are demonstrated. The key features of the proposed controller, including cable current balancing, cable current limiting, and current nulling, are illustrated. An MTDC grid is simulated using MATLAB/SIMULINK software to evaluate the steady state and dynamic performance of the proposed CFC topology. Furthermore, a low power prototype is built for a CFC to experimentally validate its performance using rapid control prototyping. Simulation and experimental studies indicate the fast dynamic response and precise results of the proposed topology. Furthermore, the proposed controller offers a real solution for power flow challenges in MTDC grids.

• 공업화학
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• 제10권2호
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• pp.237-241
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• 1999

니켈을 알루미나와 실리카 담체에 담지 한후 CFC-113 ($CF_2Cl$-$CFCl_2$)을 수소 기류 중에서 3FCl ($CF_2$=CFCl, CFC-1113)로 하는 환원반응을 실시하였다. 실리카나 알루미나의 경우 모두 활성이 급격히 저하하였으며 니켈의 함량이 증가할수록 저하속도는 현저하였다. 그러나 선택성은 80% 수준을 유지하면서 변하지 않았다. 알루미나 상에 동과 리티움을 니켈과 동시에 담지 시켰을 시는 활성과 선택성이 크게 개선되었다. 그러나 과량의 리티움의 증가는 활성과 선택성을 모두 저하시켰다. 담체로 실리카를 사용한 경우에는 활성이 급격히 저하되었는데, 이는 반응중 생성 된 HF가 Silica와 반응, $SiF_4$로 증발됨으로서 표면적이 큰 실리카 담체의 손실 또는 알카리 금속의 첨가로 인한 활성점의 감소에 의한 것으로 보여 진다.

• 공업화학
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• 제4권2호
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• pp.318-323
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• 1993

CFC-11$(CFCl_3)$의 대체품인 HCFC-123$(CF_3CHCl_2)$의 합성을 위하여 Pentachloroethane($CHCl_2CCl_3$)을 제조하고, 이것을 antimony pentahalide 촉매의 존재하에서 불화수소와 반응시켰다. $CHCl_2CCl_3$의 불소화 반응은 촉매와 반응물간의 Cl-F교환 mechanism에 의해 진행되었으며 $CHCl_2CCl_3$의 불화도는 반응온도가 높을수록 증가하는 경향을 보여 주었다. 촉매농도 또한 생성물의 불화도에 영향을 미치나 반응온도에 비해 상대적으로 낮았다. $CCl_3CFCl_2$, $CFCl_2CFCl_2$, $CF_2ClCFCl_2$와 같은 부산물의 생성원인을 규명하기 위한 실험을 실시하여 부산물 생성 mechanism을 제안하였다.

• 대한설비공학회지:설비저널
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• 제25권1호
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• pp.53-66
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• 1996

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 1992년도 제15회 대기보전학술연구발표회 요지집
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• pp.96-100
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• 1992

• 대한설비공학회지:설비저널
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• 제20권3호
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• pp.179-189
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• 1991

• 기술표준
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• 통권1호
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• pp.64-68
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• 2002