Czochralski법을 이용한 금속 단결정의 성장과 구조적, 전기적 성질에 관한 연구

박정훈,차수영,박상언,김성규,조채룡,박혁규,김형찬,정명화,정세영,Park, Jeung-Hun,Cha, Su-Young,Park, Sang-Eon,Kim, Sung-Kyu,Cho, Chae-Ryong,Park, Hyuk-K.,Kim, Hyung-Chan,Jeong, Myung-Hwa,Jeong, Se-Young 한국결정학회 2005 韓國結晶學會誌 Vol.16 No.2

It is well known that the general metals have a lot of grain boundaries. The grain boundaries play a negative role to increase the resistivity and to decrease the conductivity. The small resistivity and the large conductivity have been a goal of the material scientists, and no signal noise, perfect signal transfer, and the realization of the real sound are the dream of electronic engineers and audio manias. Generally, oxygen free copper (OFC) and Ohno continuous casting (OCC) copper cables have been used for the purpose of the precise signal transfer and low noise. However they still include a lot of grain boundaries. In our study, we have grown the single crystal by the Czochralski method and succeeded to produce single crystal wires from the crystal in the dimension of $0.5{\times}0.5{\times}2500mm$. The produced wire still possesses very good single crystal properties. We observed the structure of the wire, and measured the resistance and impedance. Glow Discharge Spectrometer (GDS) was used for analyzing the compositions of copper single crystals and commercial copper. Current-Voltage curve, resistance, total harmonic distortion and speaker frequency response were measured for comparing electrical and acoustic properties of two samples.

창립32주년 기념사

박정훈,Park, Jeong-Hun 한국화재보험협회 2005 防災와 保險 Vol.108 No.-

Atrazine의 토양 흡착 및 탈착에 미치는 접촉시간의 영향

박정훈,Park Jeong-Hun 한국지하수토양환경학회 2005 지하수토양환경 Vol.10 No.1

The effects of soil-chemical contact time (aging) on sorption and desorption of atrazine were studied in soil slurries because aging is an important determinant affecting on the sorption and desorption characteristics of organic contaminants in the environment. Sorption isotherm and desorption kinetic experiments were performed, and soilwater distribution coefficients and desorption rate parameters were evaluated using linear and non-linear sorption equations and a three-site desorption model, respectively. Aging time for sorption of atrazine in sterilized soil slurries ranged from 2 days to 8 months. Atrazine sorption isotherms were nearly linear $(r^2\;>\;0.97)$ and sorption coefficients were strongly correlated to soil organic carbon content. Sorption distribution coefficients $(K_d)$ increased with increasing aging in all soils studied. Sorption non-linearity did not increase with increased aging except for the Houghton muck soil. Desorption profiles were well described by the three-site desorption model. The equilibrium site fraction $(f_{eq})$ decreased and the non-desorbable site fraction $(f_{nd})$ increased as a function of aging time in all soils. In all soils studied, it was found that when normalized to soil organic matter content the concentration of atrazine in desorbable sites was comparatively constant, whereas that in non-desorbable site increased as aging increased. 토양과 유기화합물의 접촉시간은 흡착과 탈착의 특성에 영향을 미치는 중요한 요소 중의 하나이다. 본 연구에서는 atrazine의 토양 흡착과 탈착에 미치는 접촉시간의 영향을 연구하였다. 등온 흡착실험을 수행하여 토양과 수용액 사이의 분배계수를 구하였고, 탈착에 대한 동력학 실험을 수행하고 three-site desorption모델을 이용, 회기분석 하여 탈착속도 계수들을 추산하였다. atrazine과 토양의 접촉시간은 2일에서부터 8개월까지 변화시켰다. 2일 흡착에 대한 atrazine의 흡착등온 곡선은 거의 선형이었고$(r^2>0.97)$, 흡착분배계수는 토양의 유기탄소 함량과 강한 양의 상관관계를 가졌으며 사용한 모든 토양에서 접촉시간이 길어질수록 증가하였다. 흡착곡선에서의 비선형성은 Houghton muck토양을 제외하고는 접촉시간에 따라 증가하지 않았다. 탈착실험 분석으로부터 접촉시간이 증가함에 따라 equilibrium site분율은 감소하고 non-desorbable site 분율은 증가함을 알 수 있었다. 사용한 모든 토양에서 토양유기탄소 함량으로 표준화한 경우 desorbable sites 에서의 atrazine농도는 접촉시간에 따라 비교적 일정한 것에 비해 non-desorbable site에서의 atrazine농도는 접촉시간이 증가함에 따라 증가하였다.

Sulfur removal from coal with supercritical fluid treatment

박정훈,Yong Ou Joung,Sang Do Park 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.2

Conversion and sulfur removal of coal in sub- and supercritical water was studied in a micro reactor in the temperature range of 340-400°C and water density 0-0.27 g/cm3 for 0-90 min under N2 atmosphere. The experiments were conducted to investigate the effect of reaction temperature, pressure, time and density of water on the sulfur removal in gaseous and liquid effluents, respectively. The results show that supercritical condition is more effective than sub-critical condition to remove the sulfur from coal. It is possible to reduce 57.42% of the original sulfur in coal for the reaction time of 90 min at 400°C and 30 MPa. The main gas containing sulfur in the gaseous effluent is not SO2 but H2S, irrespective of operating condition. The sulfur removal in liquid effluents is much greater than that in gas effluents. Compared with temperature, the influence of water density and pressure is less significant.

Mouse cell에서 형개연교탕(荊芥連翹湯)의 iNOS 생성 억제 효과

박정훈,김종채,홍승욱,Park, Jung-Hoon,Kim, Jong-Che,Hong, Seung-Ug 대한한방안이비인후피부과학회 2011 한방안이비인후피부과학회지 Vol.24 No.1

Background and Objectives : The aim of this study was to investigate anti-inflammatory and anti-oxidant effects of Hyunggaeyungyo-tang(HYT) on RAW 264.7 cells. Material and Methods : Two types of experiments were implemented for this study: first, the experiment to study the anti-oxidant effect of HYT using riboflavin; second, in vitro experiment to investigate the suppression of NF-${\kappa}$B activation using RAW 264.7 cells (I${\kappa}$B kinase and induce nitric oxide synthase mRNA expression) Results : 1. The anti-oxidant effects of HYT was dose-dependantly increased. 2. The RAW 264.7cells were treated with LPS for 1 hours prior to the addition of indicated concentrations(0.4,-1.0mg/$m\ell$) of HYT, and the cells were further incubated for 24 hours. The LPS-induced IKK & iNOS mRNA expression were dose-dependantly decreased in HYT treated RAW 264.7cells. Conclusion : The results suggest that HYT is significantly effective in the treatment of inflammation through the suppression of NF-${\kappa}$B activation and iNOS production.

폐유리 발포 경량골재를 활용한 신축, 보수 및 3D 프린팅 적용 기술 소개

박정훈,Park, Jung-Hoon 한국건설순환자원학회 2020 한국건설순환자원학회지 Vol.15 No.3

RF 마그네트론 스퍼터링에서 증착거리와 증착온도가 무기 액정 배향막의 물리적 성질에 미치는 영향에 대한 연구

박정훈,손필국,김기범,박혁규,Park, Jeung-Hun,Son, Phil-Kook,Kim, Ki-Pom,Pak, Hyuk-Kyu 한국재료학회 2008 한국재료학회지 Vol.18 No.10

We present the structural, optical, and electrical properties of amorphous silicon suboxide (a-$SiO_x$) films grown on indium tin oxide glass substrates with a radio frequency magnetron technique from a polycrystalline silicon oxide target using ambient Ar. For different substrate-target distances (d = 8 cm and 10 cm), the deposition temperature effects were systematically studied. For d = 8cm, oxygen content in a-$SiO_x$ decreased with dissociation of oxygen onto the silicon oxide matrix; temperature increased due to enlargement of kinetic energy. For d = 10 cm, however, the oxygen content had a minimum between $150^{\circ}\;and\;200^{\circ}$. Using simple optical measurements, we can predict a preferred orientation of liquid crystal molecules on a-$SiO_x$ thin film. At higher oxygen content (x > 1.6), liquid crystal molecules on an inorganic liquid crystal alignment layer of a-$SiO_x$ showed homogeneous alignment; however, in the lower case (x < 1.6), liquid crystals showed homeotropic alignment.

BaTiO₃ 미세 분말의 수열합성 및 특성분석

박정훈,박상도,Park, Jung-Hoon,Park, Sangdo 한국화학공학회 2007 Korean Chemical Engineering Research(HWAHAK KONGHA Vol. No.

미세 $BaTiO_3$ 분말의 합성을 위해 함수 티타니아와 수산화바륨을 원료로 수열합성 실험을 수행하여, 반응시간, 온도, 농도 변화에 따른 전화율, 결정구조 및 생성 분말의 물성을 조사하였다. 전화율에 미치는 영향은 시간 < 온도 < 농도 순이었으며, 2.0 M의 원료를 $180^{\circ}C$에서 2 h 수열합성 시킬 때 최대 전화율을 99.5%를 얻을 수 있었다. 낮은 농도(0.25 M)에서는 고온에서도 미반응 $BaCO_3$와 미반응 $TiO_2$ 생성을 피할 수 없었으며, 이 미반응 물질들은 고온에서 $BaTi_2O_5$를 생성시켜 불순물로 존재하였다. 농도를 높일수록 합성 $BaTiO_3$ 분말의 크기는 작아졌으며, 분말의 Ba/Ti 비도 1에 접근하였다. 2.0M 이상의 농도에서는 $180^{\circ}C$, 2 h 반응에서 Ba/Ti 비는 $1{\pm}0.005$ 이였다. Hydrothermal synthesis was conducted with starting material as Barium hydroxide and hydrous titania ($TiO_2{\cdot}xH_2O$) to obtain barium titanate fine Powder. The conversion, crystal structure and properties of as-prepared powder were investigated according to reaction temperature, time and concentration. The effect of variables on conversion was in order of time < temperature < concentration and the maximum conversion reached to 99.5% in the case of hydrothermal synthesis at $180^{\circ}C$ for 2 h with 2.0 M reactant concentration. At low concentration such as 0.25 M, formation of unreacted $BaCO_3$ and $TiO_2$ was not inevitable at even high reaction temperature and these components converted into $BaTi_2O_5$ at high temperature and remained as impurity. As concentration of reactant increased, the size of as-synthesized $BaTiO_3$ powder deceased and Ba/Ti molar ratio approached into 1, showing Ba/Ti ratio of $1{\pm}0.005$ for reaction at $180^{\circ}C$ for 2 h with 2.0 M concentration.

알레르기 비염 유발 생쥐에 대한 형개연교탕(荊芥連翹湯)의 iNOS 생성 억제 효과

박정훈,홍승욱,Park, Jung-Hoon,Hong, Seung-Ug 대한한방안이비인후피부과학회 2012 한방안이비인후피부과학회지 Vol.25 No.1

Background and Objectives : Allergic rhinitis is one of the most common diseases in the otorhinolaryngology area. in oriental clinic, Hyunggaeyungyo-tang(HYT) has been used as a primary prescription to treat allergic rhinitis. However, there have been no studies so far performed on the effect of this HYT use. The purpose of this study was find out therapeutic effects of its exclusive use on the rat with allergic rhinitis. Material and Methods : Thirty BALB/c mice were divided into three group : normal group(NOR), control group(CON) inoculated with allergic rhinitis and sample group(SAM) treated with the HYT extract after it was treated the same as the control group. Rats were sensitized intraperitoneally with ovalbumin solution 4times at intervals of 2 days. After that time, rats in SAM were administered by HYT to treat the inflammation. Results : 1. The number of eosinophil in SAM noticeably decreased than CON and this decrease had probability. The inhibition of eosinophil distribution. The infiltration of eosinophil in SAM noticeably decreased than CON. 2. The damaged mucosa as disruption of cilia in respiratory cell, vacant mucose secreting cell and infiltration of inflammation intricate cells in CON were increased than NOR, but SAM same as normal configuration. Decrease of icthing and sneezing intricate neurotransmitter (substance P). Decrease of angiogenesis intricate cytokine(MIP-2). 3. Transcription factor(NF-${\kappa}B$ p65) was decreased. 4. Transcription factor inhibitor(p-$I{\kappa}B$) was decreased. 5. Inflammation cytokine(iNOS) was decreased. Conclusion : The results suggest that HYT is significantly effective in the treatment of inflammation caused by allergic rhinitis through the suppression of NF-${\kappa}B$ activation and iNOS production.

$GO_2$-Tunnel: 터널 시공 중 디지털 Face Mapping 및 3D 지질 모델링

박정훈,박성욱,김광염,Park, Jeong-Hun,Park, Seong-Uk,Kim, Gwang-Yeom 한국터널지하공간학회 2011 자연, 터널 그리고 지하공간 Vol.13 No.5