• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.1043-1046
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• 2004

The stability and electrochemical properties of a self-assembled layer of spinach ferredoxin on a quartz substrate and on a highly oriented pyrolytic graphite electrode were investigated. To fabricate the ferredoxin self-assembly layer, dimyristoylphosphatidylcholine was first deposited onto a substrate for ferredoxin immobilization. Surface analysis of the ferredoxin layer was carried out by atomic force microscopy to verify the ferredoxin immobilization. To verify ferredoxin immobilization on the lipid layer and to confirm the maintenance of redox activity, absorption spectrum measurement was carried out. Finally, cyclic-voltammetry measurements were performed on the ferredoxin layers and the redox potentials were obtained. The redox potential of immobilized ferredoxin had a formal potential value of -540 mV. It is suggested that the redox-potential measurement of self-assembled ferredoxin molecules could be used to construct a biosensor and biodevice.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.5
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• pp.525-544
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• 1999

Polycyclic aromatic hydrocarbons (PAH) were one of the first airborne pollutants to be identified as being carcinogenic. This class of compounds is ubiquitous in the urban atmosphere, and has therefore undergone considerable scrutiny for the last three decades. PAH can be formed in any incomplete combustion or high temperature pyrolytic process involving materials containing carbon and hydrogen, such as fossil fuels. In this paper, the literature on the occurrence, ambient levels, and atmospheric fate and behaviour of airbonrne PAH has been reviewed, with a particular emphasis on the role of automobile sources in PAH emissions. Sampling and analytical techniques for the determination of PAH in air have also been examined. In addition, health implications and legislative aspects of human exposure to airborne PAH have been briefly reviewed. Finally, future requirements for better understanding of the atmospheric behaviour of PAH recommended.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.950-952
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• 1998

DC Arc Plasma was applied in order to convert of hydrocabon fuels (Methane) to hydrogen, which has higher available energy. Plasma can generate very high temperatures with a high degree of control, using electricity. Plasma can be used to produce the pure hydrogen fuel, and has rapid response time. In addition, the use of plasma could provide for a greater variety of operating modes including the posibility of virtual elimination of $CO_2$ production by pyrolytic operation and could obtain byproduct (Carbonblack).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.384-384
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• 2008

그라핀 기판 제작을 위해서는 그라파이트의 탈착이 가장 핵심 기술이다. 본 연구에서는 신뢰성 있는 그라핀 기판 제작을 위해서, HOPG(Highly Ordered Pyrolytic Graphite) 기판에 고농도의 이온을 주입하고, HOPG를 이형기판에 본딩한후, 후속 열처리를 통해 HOPG를 탈착시켜 그리핀을 얻는 일련의 기본 실험에 대한 결과를 보여 주고자 한다. 기대하는 효과는 고농도의 수소/산소 이온의 경우 주입된 고농도의 수소/산소가 후속 열처리동안 이동 및 뭉침현상을 통해 HOPG기판 내에 수소압력(혹은 CO2 발생)을 증가시켜 HOPG를 자르는 것을 기대하고 있다. 일차 수소이온 주입의 실험결과, 기대와는 달리 $900^{\circ}C$ 열처리에도 절단현상이 발견되지 않아서 산소이온주입에 대한 추가실험을 진행 중이다. 그라핀 본딩의 경우 그라핀의 큰 roughness로 인해 $SiO_2$만의 Fusion 본딩은 불가능함을 여러 실험을 통해 알 수 있었고, 현재 SiO2/SOG 혹은 SiO2/Fox를 이용한 본딩실험을 진행중이다.

• Smart Structures and Systems
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• v.10 no.2
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• pp.181-192
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• 2012

Magnetic suspensions based on passive levitation of diamagnetic materials on permanent magnets provide attractive systems for several applications on the micro and meso scales. The magnetic properties of these kinds of suspensions dramatically reduce the global mechanical stiffness of the devices providing significant effects on their dynamic response. The goal of this paper is to investigate the static and dynamic behavior of magnetic suspensions with respect to its dependant parameters. Experimental measurements have been performed on the response of dedicated prototypes where the geometrical dimensions and magnetic field strength have been intended as variable parameters. Some benefits have been documented in the fields of energy harvesting and inertial sensing, while additional applications of magnetic suspensions are under investigation.

• Journal of the Korean Society of Tobacco Science
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• v.7 no.2
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• pp.169-178
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• 1985

In the previous paper, the kinetics of cellulose were described. In this study, the ability of some additives to act as a flame promoter for cellulose was investigated using dynamic thermogravimetry and differential scanning calorimetry. The treated cellulose was thermally decomposed through the two model as previously noted with the untreated cellulose. The first step was associated with the flaming combustion of volatile material released in the fraunentation process and the second was caused by the glowing combustion of carbonaceous residue. The first group of the additives, which could be divided into two groups by the pyrolytic mechanism of cellulose, appeared to catalyze the fragmentation, maximizing the degradation to produce tarry products, with gaseous flammable substrate. The heat evolved in flaming combustion mode was increased significantly by the treatment of the cellulose retained 1-5% of the first group additives.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.4
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• pp.11-15
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• 2008

Metrology tools with the ability to measure spindle motion error on the order of a nanometer are required due to recent advances in nanotechnology. We propose a direct measurement method for the radial motion error of a precision spindle using a regular crystalline lattice and a scanning tunneling microscope (STM). A highly oriented pyrolytic graphite (HOPG) crystal combined with an STM is used as a two-dimensional reference scale. The measurement principle and the preliminary experimental results are discussed in this article. The preliminary experimental results demonstrated that the proposed method has the capability to incorporate a two-dimensional encoder to measure the spindle motion error.

• Journal of the Korean Society of Tobacco Science
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• v.31 no.2
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• pp.107-114
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• 2009

In this study, we investigated the existence of melamine and cyanuric acid in cigarette smoke because leaf tobacco contains lots of nitrogen compounds and they are capable of pyrolytic synthesis while smoking. The extraction and derivatization conditions of two compounds were performed according to the procedure of U.S. Food and Drug Administration(FDA). Ky3R4F as reference cigarette was smoked on ISO condition(Puff volumne : 35 ml, duration : 60 sec, Interval : 2 sec). Compared with the results Ky3R4F and standard solution, retention time of two compounds was not corresponded. As a result, we concluded that melamine and cyanuric acid were not existed in cigarette smoke.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.663-666
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• 2000

Laser direct writing of micro-patterned copper lines has been achieved by pyrolytic decomposition of copper formate films (Cu(HCOO)$_2$$.$4H$_2$O), as a precursor, using a focused Ar$\^$+/ laser beam ($\lambda$= 514 nm) on PCB boards and glass substrates. The linewidth and thickness of the lines were investigated as a function of laser power and scan speed. The profiles of the lines were measured by scanning electron microscope (SEM), surface profiler (${\alpha}$-step) and atomic force microscopy (AFM). The electrical resistivities of the patterned lines were also investigated as a function of laser parameter using probe station and semiconductor analyzer. we compared resistivities of the patterned lines with that of the Cu bulk, respectively.

• Journal of the Korean Ceramic Society
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• v.27 no.6
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• pp.790-798
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• 1990

Al2O3 film was chemically deposited by pyrolytic decom,positio of the Al-tri-isopropoxide/N2 system at 350$^{\circ}C$, 30 and 1.86torr. FTIR analysis showed a deposited film was a hydrated alumina and transformed to an anhydrous one after heat treatment(1hr, >800$^{\circ}C$ or 4hr, >500$^{\circ}C$) in N2 atmosphere. This transformation influenced on the CV-hysteresis of Si-Al2O3 structure. Also, a pH sensitivity of EIS(Electrolyte-Insulator-Semiconductor)structure using Si-Al2O3/SiO2 film was 50mV/pH in the range of pH 3 to 7.