Lavandulyl Flavanones from <i>Sophora flavescens</i> Protect Mouse Hippocampal Cells against Glutamate-Induced Neurotoxicity <i>via</i> the Induction of Heme Oxygenase-1

Jeong, Gil-Saeng,Li, Bin,Lee, Dong-Sung,Byun, Erisa,An, Ren-Bo,Pae, Hyun-Ock,Chung, Hun-Taeg,Youn, Kwon-Ha,Kim, Youn-Chul Pharmaceutical Society of Japan 2008 Biological & pharmaceutical bulletin Vol.31 No.10

<P>Lavandulyl flavanones of <I>Sophora flavescens</I> roots are anti-malarial, anti-inflammatory, and cytotoxic. Here, we examined whether four lavandulyl flavanones, (2<I>S</I>)-2′-methoxykurarinone (1), sophoraflavanone G (2), leachianone A (3), and (−)-kurarinone (4), isolated from <I>S. flavescens</I> could protect HT22 immortalized hippocampal cells against glutamate-induced oxidative stress. Compounds 1 and 2 induced the expression of heme oxygenase (HO)-1 and increased HO activity dose- and time-dependently. These two compounds also suppressed glutamate-induced reactive oxygen species generation in HT22 cells, whereas compounds 3 and 4 were not protective. These two lavandulyl flavanones (compounds 1, 2) may protect against glutamate-induced neurotoxicity <I>via</I> HO-1 induction.</P>

폴리올법을 이용한 미립 코발트 분말 합성

Kim, Dong-Jin,Chung, Hun-Saeng,Woo, Sang-Duck,Lee, Jae-Jang 한국결정성장학회 2001 韓國結晶成長學會誌 Vol.11 No.6

균질한 형상, 좁은 입도분포 그리고 순도가 높은 미립 금속분말은 첨단산업분야에서 응용분야가 점차 확대되고 있다. 본 연구에서는 Polyol법을 이용한 마이크론 크기의 단분산 코발트 분말을 합성하였다 Polyol이 환원제 역할을 하였다. 반응온도, 반응시간, 분산제첨가 및 전구체의 농도 등을 변화시켜 코발트의 입자 크기, 형상 그리고 응집현상을 제어하고자 하였다. 최적의 합성조건은 E.G/DiE/G 부피비 1:4,$Co(OH)<_{2}$polyol 몰비 0.08~0.32 반응온도 $210^{\circ}C$, PVP/Co$(OH)_2$ 몰비 0.4이었다. Fin metal particles of uniform shape, narrow size distribution and high purity are increasingly needed for specific uses in high tech industrial applications. Polyol process for the preparation of monodispersed cobalt powders in micron size is described. In this process in inorganic precursor is reduced in liquid polyol under controlled conditions. The reducing agent is the polyol itself and reaction parameters such as the traction temperature, reaction time, addition of protective agent and concentration of the precursor are varied for controling particles size, shape and agglomeration of the metal particles. An optimum synthesis condition was achieved at E.G/DiE/G volume ratio 1:4,Co$(OH)_{2}$polyol molar ratio 0.08~0.32 reaction temperature $210^{\circ}C$, PVP/Co$(OH)_{2}$ molar ratio 0.4.

잠열저장재를 이용한 온돌판넬의 축열 및 방열특성에 관한 연구

조수(Cho Soo),유제인(Yoo Jein),정헌생(Chung Hun-saeng) 한국태양에너지학회 1990 한국태양에너지학회 논문집 Vol.10 No.2

본 연구는 염화칼슘6수화물(CaCI₂6H₂O)을 온돌판넬에 적용하여 가열시간에 따른 잠열재판넬의 축열 및 방열특성을 조사하기 위하여 같은 크기의 실험동(1.8m^L×1.8m^W×1.8m^H)을 지었다. 잠열재판넬에 적용할 알루미늄 용기는 1.6^T×9㎝^W×80㎝^H 크기로 제작하여 염화칼슘6수화물(1.25㎏)을 충진시켰다.<br/> 잠열재인 염화칼슘6수화물을 넣은 온돌판넬은 실내공기온의 변화폭을 줄이고, 잠열재의 상변화과정에서 방열되는 시간은 축열에 필요한 가열시간의 2~4배 정도였다. The present study was to investigate the use of a phase change material for hydronic radiant floor heating. Two identical unit test cells sized 1.8m^L×1.8m^W×1.8m^H were built and installed with specially designed 1.6^T×9㎝^W×80㎝^H aluminum Ondol-panels holding 1.25㎏ of calcium chloride hexahydrate(CCH) each.<br/> It was found that the Ondol-panel with CCH reduced the room temperature fluctuations and maintains the phase changing temperature for considerably long duration, 2~4 times of heating hour, over no-CCH one.

Comparison of Bioleaching Kinetics of Spent Catalyst by Adapted and Unadapted Iron & Sulfur Oxidizing Bacteria - Effect of Pulp Density; Particle Size; Temperature

( Debabrata Pradhan ),( Dong Jin Kim ),( Jong Gwan Ahn ),( Chandra Sekhar Gahan ),( Hun Saeng Chung ),( Seoung Won Lee ) 대한금속재료학회(구 대한금속학회) 2011 대한금속·재료학회지 Vol.49 No.12

Bioleaching studies of metals from a spent catalyst were conducted using both adapted and unadapted bacterial cultures. The bacterium used in this experiment was Acidithiobacillus ferrooxidans. A comparison of the kinetics of leaching was made between the two cultures by varying the leaching parameters, including the pulp density, particle size and temperature. Both cultures showed similar effects with respect to the above parameters, but the leaching rates of all metals were higher with the adapted compared to the unadapted bacterial cultures. The leaching reactions were continued for 240 h in the case of the unadapted bacterial culture, but only for 40 h in the case of the adapted bacterial culture. The leaching reactions followed first order kinetics. In addition, the kinetics of leaching was concluded to be a diffusion control model; therefore, the product layers were impervious.

국내의 풍력자원 특성 분석

박경호(Park Kyung-Ho),김건훈(Kim Keon-Hoon),정헌생(Chung Hun-Saeng) 한국태양에너지학회 1990 한국태양에너지학회 논문집 Vol.10 No.2

최근 전 세계적으로 풍력발전 기술의 급속한 발달로 인하여 풍력발전의 경제성이 과거보다 점차 향상되고 있으며, 이에국내에서의 풍력발전 가능성을 재확인하기 위한 사업의 일환으로 기상대에서 지난 10년간 관측한 풍속데이타를 Weibull 함수로 특성화하여 우리나라 전역의 풍황과 풍력자원 변화 및 분포 특성을 시간별, 월별, 계절별 및 년도별로 거시적으로 분석하였다. The recent technology of Wind Energy Conversion System(WECS) in the world is well-developed and the feasibility of WECS is better than the past time. So, it is necessary to re-analyze the characteristics of wind energy in this country.<br/> This paper deals with the analysis of wind energy distribution in Korean Peninsula, Cheju and Ullung island. The assessment was performed based on the raw data collected 64 meteorological stations for the last 10 years. The wind energy characteristics were analyzed hourly, monthly, seasonally and annually.<br/> The Weibull distribution was assumed and two parameters in all areas were calculated and the wind energy potential distribution in Korea was obtained.

규석광으로부터 직접 질화법에 의한 질화규소의 합성

손용운,주성민,정헌생,Sohn Yong-Un,Joo Sung-Min,Chung Hun-Saeng 한국재료학회 2004 한국재료학회지 Vol.14 No.5

$Si_3$$N_4$ ceramics have been identified as one of the promising structural ceramics. This study has been carried out to investigate of the synthetic behaviors of $Si_3$$N_4$ derived from domestic silica-stone by direct nitriding method. The silicon nitridation reaction has been studied in the temperature range of $1300~1550^{\circ}C$. Below the $1400^{\circ}C$, the nitriding rate was measured to be 16%. For the temperatures higher than the $1400^{\circ}C$, $\beta$-$Si_3$$N_4$ phase was formed mainly, and the nitriding rate showed above 98%. With the increasing of sample weight of silicon powder, the nitriding rate and $\beta$-$Si_3$$N_4$ phase increased at $1400^{\circ}C$ for 2 hours. The shape and particle size of$ Si_3$$N_4$ powder synthesized at $1400^{\circ}C$ for 2 hours showed the irregular angular-type and 10 $\mu\textrm{m}$, respectively.

이중 다류관 모델을 이용한 Darrieus 터어빈의 공기역학적 특성 해석

김건훈(Keon-Hoon Kim),박경호(Kyung-Ho Park),정헌생(Hun-Saeng Chung) 한국태양에너지학회 1990 한국태양에너지학회 논문집 Vol.10 No.1

수직축 다리우스 풍력 터어빈의 공기역학적 특성을 해석코자 날개요소이론과 운동량 이론에 근거하는 이중다류관모델을 정립하여 모델풍동실험과 병행하여 비교분석하였다. 이중 다류관 모델은 아직 수정 보완의 여지는 있으나 터어빈을 통과하는 유동의 변화가 심하지 않은 날개끝속도비나 회전면적비가 작은 경우에는 비교적 정확히 터어빈의 공기역학적 특성을 예측함을 알 수 있었고, 모형풍동실험을 통해 정확한 터어빈 회전수제어로서 각 특성변수들에 대한 영향을 살피었다 .<br/> 본 연구의 결과로서는 다리우스 터어빈의 설계 및 운전특성 예측에의 응용이 기대될 수 있다. The aerodynamic performances of Darrieus wind turbine were studied through the wind tunnel model tests and its analytical aerodynamic streamtube model. Hence, analytical streamtube model which is based on momentum and blade element theory is considered and the formulated model was generalized in non-dimensional type to predict the aerodynamic characteristics of Darrieus wind turbine. The analytical model was justified through the wind tunnel model tests for several experimental conditions but in the limited rages. These satisfactory comparative studies between the wind tunnel tests and the analytical predictions can be utilized for the basic reliable design of Darrieus wind turbine.

1,2,3,4,6-penta-O-galloyl-beta-D-glucose up-regulates heme oxygenase-1 expression by stimulating Nrf2 nuclear translocation in an extracellular signal-regulated kinase-dependent manner in HepG2 cells.

Pae, Hyun-Ock,Oh, Gi-Su,Jeong, Sun-Oh,Jeong, Gil-Saeng,Lee, Bok-Soo,Choi, Byung-Min,Lee, Ho-Sub,Chung, Hun-Taeg WJG Press 2006 WORLD JOURNAL OF GASTROENTEROLOGY Vol.12 No.2

<P>To examine the potency of 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG) as a hepatic heme oxygenase-1 (HO-1) inducer and its regulation in HepG2 cells.</P>

젖소의 번식장애 및 비임신진단을 위한 Milk Progesterone 측정 EIA-kit의 이용에 관한 연구

정병현,이병한,강영선,김진영,남형영,이강열,황윤식,양광헌,정길생,Chung, Byung-hyun,Lee, Byeong-han,Kang, Young-sun,Kim, Jin-young,Nam, Hyoung-young,Lee, Kang-yeol,Hwang, Yoon-sik,Yang, Kwang-hun,Chung, Kil-saeng 대한수의학회 1995 大韓獸醫學會誌 Vol.35 No.1

This study was carried out to investigate the effect, range of practice, and propriety for diagnosis of early non-pregnancies and reproductive disorders by dairy cows' milk progesterone analysis used EIA-kit of home products. The results were summarized as follows : 1. During 2 to 6 months after artificial insemination, the results of milk progesterone measurement by Home-kit and Auto ELISA reader-kit with pregnant dairy cows(152 heads) certified by rectal palpation were revealed, in Home-kit, 145 heads(95.4%) of positive reaction, 7 heads(4.6%) of quasi-positive, and 0 heads(0%) of negative among 152 heads and, in Auto ELISA reader-kit, 152 heads(100%) of positive reaction among 152 heads. 2. During 19 to 22 days after artificial insemination, the results of milk progesterone measurement by Home-kit, and thereafrer during 50 to 90 days after that, the results of pregnant test by rectal palpation were summarized as follows : 147 heads(82.1%) among 179 heads of positive reaction by Home-kit and 5 heads(31.3%) among 16 heads of quasi-positive were revealed pregnant cows by rectal palpation, and 42 heads(100%) among 42 heads of negative were non-pregnant. 3. During 19 to 22 days after artificial insemination, the results of milk progesterone measurement by Auto ELISA reader-kit, and thereafrer during 50 to 90 days after that, the results of pregnant test by rectal palpation were summarized as follows : 146 heads(86.9%) among 168 heads of positive reaction by Auto ELISA reader-kit and 6 heads(28.6%) among 21 heads of quasi-positive were revealed pregnant cows by rectal palpation, and 48 heads (100%) among 48 heads of negative were non-pregnant. 4. For the accuracy of the rectal palpation, Home-kit and Auto ELISA reader-kit were used in the cows of ovarian diseases. The results were following : in the cows of reproductive disorders expected negative milk progesterone, the accuracies of rectal palpation were the same 75.5%(40 heads among 53 heads) by Home-kit and Auto ELISA reader-kit, and in the cows of reproductive disorders expected positive milk progesterone, the accuracies of rectal palpation were 82.6%(19 heads among 23 heads) and 91.3%(21 heads among 23 heads) by Home-kit and Auto ELISA reader-kit, respectively, and the general accuracies of rectal palpation were 77.6%(59 heads among 76 heads) and 80.3%(61 heads among 76 heads) by Home-kit and Auto ELISA reader-kit, respectively.

Effect of a glass addition on the ceramic layer prepared by a thermite reaction under a centrifugal force

Minh-Tung Le,Cheol-Gi Kim,Yang-Kyu Ahn,Hun-Saeng Chung 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.5

A ceramic layer was produced on a steel pipe inner surface by a centrifugal thermite process. A powdery mixture of ferric oxide and aluminum was used with the glass whose major compositions were SiO2, Na2O, CaO, and MgO. The ceramic layer consisted of the crystalline structures of corundum (α-Al2O3) and hercynite (FeAl2O4). The amorphous phases of Ca3Al2(SiO4)3, MgFeAlO4 and NaAlSiO4 in the ceramic layer were found to be responsible for a significant improvement of the dense structure. The glass addition increased the density of the ceramic layer from 2.9 g/cm3 to 3.6 g/cm3 and the hardness from 1,450 to 1,800 Hv. A ceramic layer was produced on a steel pipe inner surface by a centrifugal thermite process. A powdery mixture of ferric oxide and aluminum was used with the glass whose major compositions were SiO2, Na2O, CaO, and MgO. The ceramic layer consisted of the crystalline structures of corundum (α-Al2O3) and hercynite (FeAl2O4). The amorphous phases of Ca3Al2(SiO4)3, MgFeAlO4 and NaAlSiO4 in the ceramic layer were found to be responsible for a significant improvement of the dense structure. The glass addition increased the density of the ceramic layer from 2.9 g/cm3 to 3.6 g/cm3 and the hardness from 1,450 to 1,800 Hv.