• Corrosion Science and Technology
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• v.9 no.6
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• pp.300-309
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• 2010

The influences of sensitization on localized corrosion resistance of 304 stainless steel, were investigated, using micro-dropletcell techniques. Micro-droplet cell allows one to align the micro-electrode to the desired spot of the working electrode and measure directly local current with the potentiodynamic polarization, linear polarization and a.c. impedance. Micro-electrochemical tests were carried out inside of the grain and on grain boundaries separately. It was found that sensitization decreased the pitting potential, increasing corrosion current density around grain boundaries. Galvanic current density was also measured between grain and grain boundaries.

• Journal of Society of Preventive Korean Medicine
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• v.13 no.2
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• pp.103-113
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• 2009

This study was performed to evaluate the effect of HCB on the bone mass and its related factors in estrogen-deficient animal model. The model rats of osteoporosis showed a significant decrease in bone density, bone ash density, calcium content of femur bone. At the 14th day after ovariectomy-surgery, rats were administered with HCB, extract of Houyttnia cordata, per orally, and continued for 10 weeks. And osteoporosis related parameters were determined to investigate the effect of HCB. Osteoporotic rats showed lower serum estrogen level, higher body weight than normal rats, and showed atrophy of uterine horns.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.11a
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• pp.14-16
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• 1994

The development of proton exchange membrane fuel cells(PEMFCs) with high energy efficiencies and high power densities is gaining momentum because their performance characteristics are attractive for terrestrial(power sources for electrical vehicles, stand-by power), space and underwater application[1]. Fuel cells are capable of running on non-petroleum fuels such as methanol, natural gas or hydrogen and also have major impact on improving air quality. They virtually eliminate particulates, NO$_{x}$, SO$_{x}$, and significant reduce hydrocarbons and carbon monoxide. Especially, fuel cell-battery hybrid power sources appear to be well suited to overcome both the so-called battery problem(low energy density) and the fuel cell problem(low power density)[2].[2].

• Journal of Integrative Natural Science
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• v.15 no.4
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• pp.171-177
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• 2022

ROS1 (c-ros oncogene) is one of the gene with mutation in NSCLC (non-small cell lung cancer). The increased expression of ROS1 is leading to the increase proliferation of cell, cell migration and survival. Crizotinib and Entrectinib are the drugs that have been approved by FDA against ROS1 protein, but recently patients started to develop resistance against Crizotinib and there is a need of new drug that could act as an effective drug against ROS1 for NSCLC. In this study, we have performed virtual screening, where compounds are taken from Zinc 15 dataset and molecular docking was performed. The top compounds were taken based upon their binding affinity and their interactions with the residues. The compounds stability and chemical reactivity was also studied through Density Functional theory and their properties. Further study of these compounds could reveal the required information of ROS1-inhibitor complex and in the discovery of potent inhibitors.

• Journal of Plant Biotechnology
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• v.36 no.1
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• pp.7-12
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• 2009

This study was conducted to establish the optimal suspension culture system for both the propagation of embryogenic cells (ECs) and the induction of somatic embryos (SEs) of Kalopanax septemlobus. The proliferation rate of ECs was reduced as the inoculum density was increased; the highest rate was obtained when 0.1 g/100 ml of cells was initially inoculated. According to the analysis of cell growth pattern and cell growth cycle (G1, Sand G2/M), the cell growth started in 5 days culture initiation, grew rapidly until 15 days and then decreased gradually. Distinctive changes of the cell growth cycle by the culture periods was also observed; the growth cycle was doubled from initial 5.6% to 11.7% of S stage in 5 days culture and then reached in stable stages again. Therefore, the results indicated that a 15-day-cycle was the optimal culture period for the propagation of the ECs through the suspension culture. Furthermore, the cell inoculum density was also important for the induction of SE; more than 65% of SEs at the torpedo stage was induced by using the low level of cell inoculum (0.5 g/L), while the higher inoculum densities were rapidly reduced the proportion of SEs at that stage. Although the higher inoculum density delayed the development of SE, it did not affect the proportion of SEs at the globular and heart stage. In conclusion, this study showed that the suspension culture of the Kalopanax septemlobus ECs through the control of inoculum density was an efficient way for both the propagation of ECs and the induction of SEs, suggesting that the development of this system might help to reduce the culture period for the somatic embryo production.

• Clean Technology
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• v.18 no.4
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• pp.426-431
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• 2012

Carbon-rich coal can be utilized as a fuel for direct carbon fuel cell (DCFC). However, left-behind ash after the electrochemical oxidation may hinder the electrochemical reactions. In this study, we produced ash-free coal (AFC) by thermal extraction and then tested it as a fuel for DCFC. DCFC was built based on solid oxide electrolyte and the electrochemical performance of AFC mixed with $K_2CO_3$ was compared with AFC only. Significantly enhanced power density was found by catalytic steam gasification of AFC. However, an increase of the power density by catalytic pyrolysis was negligible. This result indicated that a catalyst activated the steam gasification reactions, producing much more $H_2$ and thus increasing the power density, compared to AFC only. Results of a quantitative analysis showed much improved kinetics in AFC with $K_2CO_3$ in agreement with DCFC results. A secondary phase of potassium on yttria-stabilized zirconia (YSZ) surface was observed after the cell operation. This probably caused poor long-term behavior of AFC with $K_2CO_3$. A thin YSZ (30 ${\mu}m$ thick) was found to be higher in the power density than 0.9 mm of YSZ.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.4
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• pp.393-404
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• 2014

Unmanned aerial vehicles (UAVs) have been applied to not only military missions like surveillance and reconnaissance but also commercial missions like meteorological observation, aerial photograph, communication relay, internet network build and disaster observation. Fuel cells make UAVs eco-friendly by using hydrogen. Proton exchange membrane fuel cells (PEMFCs) show low operation temperature, high efficiency, low noise and high energy density and those characterisitcs are well fitted with UAVs. Thus Fuel cell based UAVs have been actively developed in the world. Recently, fuel cell UAVs have started to develope for high altitude UAVs because target altitude of UAVs is expanded upto stratosphere altitude. Long endurance of UAVs is essential to improve effects of the missions. Improvement of UAV endurance time could be fulfilled by developing a hydrogen fuel storage system with high energy density and reducing the weight of UAVs. In this paper, research trend and analysis of fuel cell UAVs are introduced in terms of their altitude and endurance time and then the prospect of fuel cell UAVs are shown.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.341-342
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• 2001

High cell density cultivation of Pseudomonas putida is often necessary for the VOC removal bioreactor. Supplying the feeding solution of C and N sources could accelerate the growth of cells. We changed the component of feeding solution and feeding time. showing that P. putida could be grown to a high density.

• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.4
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• pp.205-210
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• 2003

A 3-Transistor cell CMOS OTP ROM array using standard CMOS antifuse (AF) based on permanent breakdown of MOSFET gate oxide is proposed, fabricated and characterized. The proposed 3-T OTP cell for ROM array is composed of an nMOS AF, a high voltage (HV) blocking nMOS, and cell access transistor, all compatible with standard CMOS technology. The experimental results show that the proposed structure can be a viable technology option as a high density OTP ROM array for modern digital as well as analog circuits.

• Journal of the Korean Ceramic Society
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• v.34 no.3
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• pp.225-232
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• 1997

The performance characteristics of high rate discharge LiSOCl2 cells are highly affected by carbon cathode. During the cell discharge, SOCl2 reduction takes place at the porous carbon cathode, resulting in the precipitation of reaction products, mainly LiCl, within the pores of the substrate. This leads to eventual passivation of the cathode surface and resulting cell failure. To improve the cathode performance, we ex-amined discharge reactions of cathodes (half-cell, 50 mA/$\textrm{cm}^2$ constant current) with various surface density and thickness. The carbon cathode with the optimum capacity for our application is surface density 0.04 g/$\textrm{cm}^2$ and thickness 1.4mm carbon. The carbon cathode with surface density 0.04g/$\textrm{cm}^2$ and thickness 1.4 mm exhibits decreased polarization, increased discharge duration time and capacity (Ah/$\textrm{cm}^2$) as compared with that with surface density 0.04g/$\textrm{cm}^2$ and thickness 0.8mm. The porosities analyses on the two carbon cathodes show that total pore volume of the carbon cathode with thickness 1.4 mm is larger than that with thickness 0.8mm. The increased volume of mesopores (0.05$\mu$m~0.5$\mu$m) and macropores(>0.5$\mu$m) is ob-served with the carbon cathode with thickness 1.4mm as compared with that with thickness 0.8mm, which can be related with the observed capacity increase. We observed LiCl crystals, cubic crystallites and fused, plate-like aggregates, and some elemental S as discharge products by EDS and XRD.