• Korean Journal of Materials Research
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• v.22 no.3
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• pp.159-167
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• 2012

Hydrogen is in the spotlight as an alternative next generation energy source for the replacement of fossil fuels because it has high specific energy density and emits almost no pollution, with zero $CO_2$ emission. In order to use hydrogen safely, reliable storage and transportation methods are required. Recently, solid hydrogen storage systems using metal hydrides have been under extensive development for application to fuel cell vehicles and fuel cells of MCFC and SOFC. For the practical use of hydrogen on a commercial basis, hydrogen storage materials should satisfy several requirements such as 1) hydrogen storage capacity of more than 6.5wt.% $H_2$, moderate hydrogen release temperature below $100^{\circ}C$, 3) cyclic reversibility of hydrogen absorption/desorption, 4) non toxicity and low price. Among the candidate materials, Li based metal hydrides are known to be promising materials with high practical potential in view of the above requirements. This paper reviews the characteristics and recent R&D trends of Li based complex hydrides, Li-alanates, Li-borohydrides, and Li-amides/imides.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.1212-1213
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• 2004

The plasmid was used pBR 322 and ${\varphi}X174$ RF DNA. In neutron experiment, damage of pBR 322 and ${\varphi}X174$ RF DNA were observed according to increasing concentration of BSH and neutron dose. Damage of plasmid DNA appeared obvious by increasing of BSH and neutron irradiation. In ${\gamma}-$ radiation experiment, it was carried out like above neutron experiment but damages of two plasmid appeared no differences from the control unlike neutron result.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.764-767
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• 2004

This paper present the temperature control of aluminum plate using Peltier element. Peltier effect is heat pumping phenomena by electric energy as one of the thermoelectric effect. So if current is asserted to Peltier element, it absorbs heat from low temperature side and emits to high temperature side. In this experiment, Peltier element is used to control the temperature of small aluminum plate with ON/OFF control scheme and fan ON/OFF. As the result of experiments, it is proper to act fan only while cooling duration and there exist a proper cooling current to drop temperature rapidly. It takes about 100sec to increase to 7$0^{\circ}C$ and drop to 35$^{\circ}C$ of aluminium plate temperature and about 90sec to increase to 7$0^{\circ}C$ and drop to 4$0^{\circ}C$ in ambient temperature 3$0^{\circ}C$ while fan is on only in cooling duration. Future aim is to realize more rapid temperature control and develop SMHA(special metal hydride actuator) by using Peltier element to heating and cooling.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.101-101
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• 2003

Al 박막의 화학증착(CVD)과 Al-Cu 합금박막의 물리증착(PVD)을 조합하는 CVD-PVD Al 공정은 수평방향의 배선과 수직방향의 via를 동시에 형성할 수 있으므로 공정단순화 및 생산원가절감 측면에서 장점이 있어서 DRAM 둥의 반도체 소자의 배선공정으로 매우 유망하다[1]. 본 연구에서는 CVD-PVD Al 공정을 이용하여 초고집적소자의 Al via와 Al 배선을 동시에 형성할 때 층간절연막의 영향을 조사하고 그 원인을 규명하였다. Al CVD를 위한 원료기체로는 dimethylaluminum hydride [($CH_3$)$_2$AlH]를 사용하였고 PVD는 38$0^{\circ}C$에서 실시하였다 층간절연막에 따른 CVD-PVD Al의 via hole 매립특성을 조사한 결과, high-density plasma(HDP) CVD oxide의 경우에는 via hole 매립특성이 우수하였으나, hydrogen silscsquioxane (HSQ)의 경우에는 매립특성이 우수하지 않아서 via 저항이 불균일 하였다. 이는 via 식각 후 wet cleaning 과정에서 HSQ에 흡수된 수분이 lamp를 이용한 degassing 공정에 의해서 완전히 제거되지 않아 CVD-PVD 공정 중에 탈착되어 Al reflow에 나쁜 영향을 미치기 때문으로 판단된다. CVD-PVD 공정 전에 40$0^{\circ}C$, $N_2$ 분위기에서 baking하여 HSQ 내의 수분을 충분히 제거함으로써 via 매립특성을 향상시킬 수 있었다. CVD-PVD Al 공정은 aspect ratio 10:1 이상의 via hole도 완벽하게 매립할 수 있었고 이에의해 제조된 Al 배선은 기존의 W plug 공정에 의해 제조된 배선에 비해 낮은 via 저항을 나타내었다.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.9
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• pp.32-37
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• 2008

Freestanding hydride vapor phase epitaxy grown GaN(Gallium Nitride) substrates subjected to various polishing methods were characterized for their surface and subsurface conditions, Although CMP(Chemical Mechanical Polishing) is one of the best approaches for reducing scratches and subsurface damages, the removal rate of Ga-polar surface in CMP is insignificant($0.1{\sim}0.3{\mu}m$/hr) as compared with that of N-polar surface, Therefore, conventional MP(Mechanical Polishing) is commonly used in the GaN substrate fabrication process, MP of (0001) surface of GaN has been demonstrated using diamond slurries with different abrasive sizes, Diamond abrasives of size ranging from 30nm to 100nm were dispersed in ethylene glycol solutions and mineral oil solutions, respectively. Significant change in the surface roughness ($R_a$ 0.15nm) and scratch-free surface were obtained by diamond slurry of 30nm in mean abrasive size dispersed in mineral oil solutions. However, MP process introduced subsurface damages confirmed by TEM (Transmission Electronic Microscope) and PL(Photo-Luminescence) analysis.

• Journal of Electrical Engineering and Technology
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• v.8 no.6
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• pp.1431-1438
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• 2013

A pack-level battery hardware-in-the-loop simulation (B-HILS) platform is implemented. It consists of dynamic vehicle models using PSAT and multiple control interfaces including real-time 3D driving and GPS mode. In real-time 3D driving mode, user can drive a virtual vehicle using actual drive equipment such as steering wheel and accelerator to generate the cycle profile of the battery. In GPS mode, actual road traffic and terrain effects can be simulated using GPS data while the trajectory is displayed on Google map. In the latter part of the paper, several performance tests of an actual lithium-polymer battery pack are carried out utilizing the developed system. All experiments are conducted as parts of actual development process of a commercial battery pack adopting 2nd generation Prius as a target vehicle model. Through the experiments, the low temperature performance and fuel efficiency of the battery are quantitatively investigated in comparison with the original nickel-metal hydride (NiMH) pack of the Prius.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.3
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• pp.461-467
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• 2008

It was studied the effect of a pre-deposited ultrathin Al layer as part of a buffer layer for the growth of GaN. AlN buffer layers were deposited on a Si(111) substrate using an RF sputtering technique, followed by GaN using hydride vapor phase epitaxy (HVPE). Several atomic layers of Al were deposited prior to AlN sputtering and the samples were compared with the others grown without pre-deposition of Al. And it was also studied the influence of AlN buffer layer thickness on the growth of GaN. The peak wavelength of the photoluminescence (PL) was varied with increasing the thickness of the GaN and AlN layers. The optimum thickness of AlN on a Si(111) substrate with an ultrathin Al layer was about $260{\AA}$. Scanning electron microscope (SEM) images showed coalescent surface morphology and X-ray diffraction (XRD) showed a strongly oriented GaN(0002) peak.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.10
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• pp.60-67
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• 2006

This paper presents the temperature control in aluminum plate with Peltier module. From the experimental work, Peltier module is used to control the temperature of small aluminum plate for both heating and cooling with the control of current and fan ON/OFF. And current control of Peltier module was accomplished by PWM method. As a result of experiments, it is proper that operate cooling fan only while cooling duration and there exist a proper cooling current to drop temperature rapidly. It takes about 125sec to control temperature of aluminium plate between $30^{\circ}C$ and $70^{\circ}C$ and about 70sec between $40^{\circ}C$ and $60^{\circ}C$, in ambient temperature $28^{\circ}C{\sim}29^{\circ}C$ while cooling fan is operated only cooling duration. With the cooling current, temperature control of aluminum plate was accomplished more rapidly in comparison without cooling current. Future aim is to realize more rapid temperature control and develop SMHA(special metal hydride actuator) by using Peltier module as a heating and cooling source.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.73-73
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• 1997

A series of 4-phenyl-1-(indoline-5-sulfonyl)-2-imidazolone derivatives has been synthesized starting from 2-bromoacetophenone. Reaction of 2-aminoacetophenone obtained from 2-bromoacetophenon by Delepin synthesis and potassium cyanate affords 1,3-dihydro-4-phenyl-2-imidazolone. This key intermediate was treated with sodium hydride and N-trifluoroacetyl-indoline-5-sulfonylchloride, and trifluoroacetyl group was deprotected to give 4-Phenyl-1-(indoline-5-sulfonyl)-2-imidazolone. Various substituents were introduced on the nitrogen of indoline. Antitumor activity of this series of compound was evaluated by MTT method. Nearly all of the compounds showed broad-spectrum activity.

• The Journal of Pediatrics of Korean Medicine
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• v.8 no.1
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• pp.59-74
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• 1994

The Study was performed on the anticonvulsive effects of Woohwangporyonghwan(WPH) and Woohwangporyonghwan except CINNABARIS and REALGAR(WPHCR) in ICR mice pretreated with strychnine, picrotoxin, and caffeine as convulsive agents, and also was done on the accumulation of Hg & AS in organs of ICR mice by ICP hydride generation method. The results were obtained as follows: 1. WPH and WPHCR group showed significant effect in delaying the onset of convulsion induced by strichine, but time to death was effective only in WPHCR group. 2. WPH and WPHCR group were significantly effective in delaying convulsion induced by picrotoxin, and time to death. 3. The anticonvulsive effect of WPH and WPHCR group was not found convulsion induced by caffeine. 4. The accumulation of Hg, AS in liver and kidney of ICR mice was not determined below 50ng/g and below 80ng/g respectively. From the above results it could be concluded that WPH and WPHCR group were effective in the convulsions induced by strychnine and picrotoxin, although the accumulation of Hg & As in liver and kidney was not proved, further study might be necessary to prove the drug safety of WPH included CINNABARIS and REALGAR.