• Journal of the Korean Vacuum Society
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• v.15 no.2
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• pp.216-222
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• 2006

In this paper, we investigated the effect of hydrogen-plasma (H-plasma) treatment on the electrical and optical properties of a quantum dot infrared photodetector (QDIP) with a 5-stacked InAs dots in an InGaAs/GaAs well structure and $Al_{0.3}Ga_{0.7}As/GaAs$ SL (superlattice) current blocking layer. It has been observed that H-plasma treatment didn't affect the band structure of QDIP. It has been also observed that the H-plasma treatment on the QDIP not only enhance the electrical property of QDIP by curing the defect channels in $Al_{0.3}Ga_{0.7}As/GaAs$ SL but also introduce defects in QDIP structure. The H-plasma treatment for 10 min with 20 W of RF power provided the lowest dark current, which made it possible to measure the photo-current (PC) of QDIP whose PC was not detectable without the H-plasma treatment due to the high dark current.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.6
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• pp.239-244
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• 2019

Two hydrogenation surface modifications, namely hydrogen atmosphere heat treatment and hydrogen plasma treatment, were found to lead to improved dispersion of nanodiamond (ND) seed particles and enhanced nucleation density for deposition of smooth ultrananocrystalline diamond (UNCD) film. After hydrogenation, the C-O and O-H surface functionalities on the surface of nanodiamond particles were converted to the C-H surface functionalities, and the Zeta potential was increased. As the degree of dispersion was improved, the size of nanodiamond aggregates decreased significantly and nucleation density increased dramatically. After hydrogen heat treatment at 600℃, average size of ND particles was greatly reduced from 3.5 ㎛ to 34.5 nm and a very high nucleation of ~3.9 × 10¹¹ nuclei/㎠ was obtained for the seeded Si surface.

• Clean Technology
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• v.18 no.4
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• pp.360-365
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• 2012

With rapid increase in municipal solid waste (MSW) due to the rising economy, solid waste gasification emerges as one of the promising technologies. Separation of the carbon monoxide (CO) and hydrogen ($H_2$) from syngas obtained by gasification of MSW was studied using the polyamide composite membrane. The separation characteristics of the CO and $H_2$ were studied at different gas flow rates and stage cuts. The permeability of CO and $H_2$ along with the selectivity of $H_2$ with respect to CO was obtained. Furthermore, the Arrhenius plots were obtained to estimate the activation energies of CO and $H_2$ permeabilites.

• Resources Recycling
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• v.10 no.1
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• pp.25-31
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• 2001

The heat treatment of PVC film containing PVC 65ft, DOP (Dioctyl Phthalate) 32% as plasticizer, Ca-Zn stearates and sur-face agent was performed under several conditions to study the dehydrochlorination of PVC and char production. In the case of $H_2$ $SO_4$, the dehydrochlorination was ca.100% at $250^{\circ}C$ for 3h. The char involving the smaller pores was produced with hydro-thermal treatment. The pore size became small with increasing the treatment time and temperature. In the case of treatment with $Ca(OH)_2$, the sizes of pores produced in char were about sever ~10 $\mu\textrm{m}$ at$ 225^{\circ}C$ for 12h. In the case of $_2$$SO_4$, the size of pores were about 1 $\mu\textrm{m}$ in 5M $_H2$$SO_4$for 12h.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.191-194
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• 2004

Ferroelectric $Pb(Zr_{0.52}Ti_{0.48})O_3$ (PZT) 박막을 $Pt(111)/Ti/SiO_2/Si$ 기판위에 증착되었고, 수소 후열처리 후의 특성변화를 연구하였다. 동시에 10 nm의 $(Pb_{0.72}La_{0.28})Ti_{0.94}O_3$ (PLT) buffer를 사용한 PZT 박막의 수소 후열처리 효과를 관찰하였다. PZT 박막의 경우, 수소 후열처리 전과 후에 강유전 특성이 현저하게 감소한 반면, PLT buffer가 사용된 PZT 박막의 경우, 강유전 특성에 거의 변화가 없었다. 이는 PLT buffer를 사용함으로써 PZT 박막의 배향성이 향상되고, 이에 따라 forming gas에 의한 수소원자가 박막 내로의 침투가 어렵게 된다. 따라서 수소원자에 대한 PZT 박막의 열화되는 현상이 buffer를 사용하는 경우, 거의 나타나지 않게 된다.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11a
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• pp.133-139
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• 1996

PWR 원전에서의 원자로 정지시 일차측 화학제어 특성을 고찰하고 제어조건을 검토하여 국내 PWR 일차측 CRUD 제거를 위한 원자로 정지시 화학처리 조건을 도출하였다. 주요 정지시 화학처리 조건으로, 조기붕소화, 산성-환원 분위기 조성 (수소농도 $\geq$ 15cc/kg- $H_2O$), 과산화수소에 의한 산소화 (주입온도 82$^{\circ}C$, 주입농도 2~8 ppm) 및 정화 탈염기 유량을 최대로 하는 운전을 제시하였다.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.2
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• pp.29-33
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• 2002

Various nanometer-scale structures are fabricated on hydrogen-passivated p-type Si(100) surface by scanning probe microscopy(SPM). The hydrogen-passivation is performed by dipping the samples in diluted 10% HF solution for one min.. Pt alloy wires are used for tips and the tips are made by cutting the wires at 45$^{\circ}$ slanted. Various line features are fabricated in various bias voltage. The optimal structure is the line of about 30 nm width on 1.7V bias voltage and 1 nA tunneling current.  

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.263-266
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• 2013

It was investigated the electrochemical characteristics of the Ni-MH battery by hydrophilic process. For adopting the Ni-MH battery in water-electrolyte, polyolefin separator was processed the hydrophilic treatment. No treatment sample did not meet KS standard (KSC 8544) but hydrophilic treatment ones satisfied with the KS standard in electrochemical characteristics, such as discharge performance, retention capacity, and cycle performance. All hydrophilic treatment samples showed similar battery performances. Among them, sulfonation treatment sample exhibited the highest value in aspect of capacity retention rate (> 88%). Furthermore, fluoride treatment sample showed the best cycle performance during battery test. This sample maintained a good cycling performance until $1,480^{th}$ cycle, which was about 3 times as compared with that of KS standard (500 cycle).

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.2
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• pp.41-48
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• 2011

In this study, the soil remediation by landfarming was carried out using microbial activators. Feasibility studies and reduction capacity of TPH(Total Petroleum Hydrocarbons) were investigated in order to find out how fast and eco-friendly the contaminated soil can be recovered. The lab-test confirmed not only the performance and degradation efficiency of microbial activators but also the effect of TPH reduction in the contaminated soil. The optimum growth conditions for indigenous microorganisms were identified using microbial activators. Based on the results of TPH removal, although there had been a little of difference in between natural decomposition and microbial activators until 20 days, the sample groups of microbial activators were higher than the control ones after 20 days. Microbial activators were applied to the field experiments on landfarming. Based on the results of removal rate in each floor of soil, it was found that the removal rates were 85.8 % in the upper, 84.4 % in the middle, and 66.10 % in the bottom. Considering that the reduction rate of TPH for the control group averaged 71.1%, the microbial activators might not be fully transferred into the bottom, which resulted from the piles of soil. As the piles have already reached 1 m in the field experiments, the low piles of soil under 0.6 m may enhance the treatment efficiency of TPH.

• 한국전기화학회:학술대회논문집
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• 1998.10a
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• pp.96-96
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• 1998