• 한국재료학회지
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• 제9권11호
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• pp.1129-1136
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• 1999

TEMAT precursor를 사용하여 다양한 증착 조건으로 ICP-CVD 방법으로 Si(100) 기판 위에 TiN 박막을 형성하였다. 형성된 TiN 박막의 결정상, 미세구조, 그리고 전기적 특성은 XRD, XPS, HRTEM, 그리고 전기적 측정으로 특성을 조사하였다. BI 구조를 갖는 다결정 TiN 박막은 기판의 온도가 $200^{\circ}C$ 이상의 온도에서 형성되었다. TiN(111) 박막은 기판의 온도가 $300^{\circ}C$에서 TEMAT, $\textrm{N}_{2}$, 그리고 Ar 가스의 유량이 10, 5, 그리고 5sccm으로 반응로에 주입할 때 형성되었다. TiN/Si(100) 계면은 TiN과 $\textrm{SiO}_2$사이에 계면반응이 없었으며 평탄하였다. 기판의 온도가 $500^{\circ}C$에서 형성된 TiN 박막의 비저항, carrier 농도와 이동도는 21 $\mu\Omega$cm, 9.5$\times\textrm{10}^{18}\textrm{cm}^{-3}$와 $462.6\textrm{cm}^{2}$/Vs으로 주어졌다.

• 한국대기환경학회지
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• 제17권2호
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• pp.133-145
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• 2001

The receptor modeling is one of the statistical methods to achieve reasonable air pollution strategies. The pur-pose of this study was to survey the concentration variability oi inorganic elements and ionic species in the PM-10 particles, to qualitatively characterize emission sources by an advanced algorithm called positive matrix factoriza-tion(PMF) as a receptor model that can strictly provide results in every loading matrix. A total of 254 samples was collected by a PM-10 high volume air sampler from Mar. 1997 to Feb. 1998 in Kyung Hee University at Suwon Campus. Fourteen chemical species(Zn, Cu, Fe, Pb, Al, Mn, $Na^{+}$, NH$_4$+, $K^{+}$, $Mg^{2+}$, $Ca^{2+}$, $SO_4^{2-}$, $NO_{3}^{-}$, and $Cl^{-}$) were determined by AAS and IC methods. The study results showed that the average monthly concentration of PM-10 particles were 86.3$\mu\textrm{g}$/$\textrm{m}^3$ in March (maximum) and 28.5$\mu\textrm{g}$/$\textrm{m}^3$ in August(minimum), respectively. The concentrations of Na+, NH$_4$+, $K^{+}$ and $Cl^{-}$ in winter, $Mg^{2+}$, $Ca^{2+}$ and $NO_{3}^{-}$, in spring, and $SO_4^{2-}$ in summer showed the largest peak concentration for the respective season. Through and app-lication of a PMF program of Pm-10 concentration data of Suwon, 9 sources were qualitatively identified , such as incineration source, oil burning source, soil related source, open burning source automobile source, coal burning sources, secondary sulfate related source, and secondary nitrate related source.

• 식물병연구
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• 제8권3호
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• pp.171-174
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• 2002

2000년 가을에 경기도 여주의 가지재배하우스포장에서 흰가루병이 발생하여 병원균의 형태 등을 조사하였다. 병징은 잎의 앞면, 뒷면과 잎자루에서 흰가루의 균총이 형성되어서 진전됨에 따라서 잎이 황화되어 말라서 결국 낙엽이 되었다. 이 병원균의 분생포자는 분생자경의 끝에 연쇄적으로 생기며 , 무색, 단세포, 타원형내지 장타원형으로 피브로신체를 가지고 있으며, 그 크기는 25~40$\times$15~22 $\mu\textrm{m}$ 이었다 분생포자의 발아관은 단순발아관이며,부착기는 뚜렷하지 않았고,분생자경은 거의 수직으로 분지하였고, 기부는 대부분 직선상이었으며, 그 길이는 47~100 $\mu\textrm{m}$ 이었다. 기부세포는 길이가 15-81 $\mu\textrm{m}$(평균 44$\mu\textrm{m}$), 폭이 10~16 $\mu\textrm{m}$ (평균 13 $\mu\textrm{m}$)이었다 그리고 분생자경상의 연쇄상 미성숙 분생포자들이 곡상외선(crenate edge)을 가지고있었다. 이상의 결과로부터 Sphaerotheca fusca에 의한 가지흰가루병으로 동정되어 국내에서 처음으로 보고한다.

• 한국식품저장유통학회지
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• 제5권3호
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• pp.207-210
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• 1998

풋고추를 수확한 다음 신선도를 유지할 수 있도록 하기 위하여 산소와 이산화탄소의 투과도가 서로 다른 LDPE, SM250, CPP 및 MPD의 4가지 포장재를 사용하여 풋고추를 포장한 다음 1$0^{\circ}C$에서 저장하면서 품질특성을 측정하였다. LDPE로 포장한 시험구는 일반적으로 고추의 저장에 적합하다고 알려진 산소 농도 3-5%, 이산화탄소 농도 5% 이하의 공기 조성을 유지하였으며, 무게, ascorbic acid 함량 및 총균수에 있어서도 다른 포장재료에 비하여 우수한 특성을 나타내어 풋고추의 신선도를 유지하는 데에 적합한 플라스틱 포장재로 생각되었다.

• Toxicological Research
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• 제13권3호
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• pp.307-310
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• 1997

The local irritation study (skin & occular irritation tests) of CJ-50001, a rG-CSF (recombinant granulocyte-colony stimulating factor) was performed in Japanese White rabbits. CJ-50001 was administered at a dose of 150 $\mu\textrm{g}$/rabbit (300$\mu\textrm{g}$ /ml, 0.5 ml) to the bare skin and at a dose of 30 $\mu\textrm{g}$/rabbit (300 $\mu\textrm{g}$/ml, 0.1 ml) to the conjunctival sac of the eye, respectively. In these experiments, there were no clinical signs which were related to CJ-50001 compared with control group. In conclusion, CJ-50001 doesn't have any irritating activity to skin and eye as 0.03% solution.

• 한국주거학회논문집
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• 제13권6호
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• pp.41-48
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• 2002

The purpose of this study is, by the method of the internet-based survey, to understand the relations between the residential condition and the characteristics of energy consumption. The followings are the results of this study. $\circled1$ Among 601 responses, evaluable 329s means that the user fully understanding what this survey is for. $\circled2$ Gas-or oil-burners occupy 80% of heater. $\circled3$ Contrary to expectations, we can not find out the relations between the cooling area and the cooling capacity of Air-conditioners. $\circled4$ There is no relation between the direction of apartment and the cooling capacity, neither. $\circled5$ During the summer, average and maximum monthly electric fare for cooling is ￦198/$\textrm{m}^2$ and ￦461/$\textrm{m}^2$, respectively. $\circled6$ And during the winter, average and maximum monthly electric fare for heating is ￦335/$\textrm{m}^2$ and ￦484/$\textrm{m}^2$, respectively.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.631-636
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• 2002

The purpose of this study was to present the method to choose the optimization machining condition for the wire electric machine. This was completed by examining the ever- changing quality of the material and by improving the function of the wire electric discharge machine. Precision metal mold products and the unmanned wire electric discharge machining system were used and then applied in industrial fields. This experiment uses the wire electric discharge machine with brass wire electrode of 0.25mm. To measure the precision of the machining surface, average values are obtained from 3 samples of measures of center-line average roughness by using a third dimension gauge and a stylus surface roughness gauge. In this experiment, we changed no-node voltage to 7 and 9, pulse-on-time to $6\mu\textrm{s}$, $8\mu\textrm{s}$ and $10\mu\textrm{s}$, pulse-off-time to $8\mu\textrm{s}$, $10\mu\textrm{s}$ and $13\mu\textrm{s}$, and experimented on wire tension at room temperature by 1000gf, 1200gf, and 1400gf, respectively

• 한국세라믹학회지
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• 제34권8호
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• pp.854-860
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• 1997

The tribological property of ceramics is very important for use in seal rings, pump parts, thread guides and mechanical seal, etc. In the present study, which RBSC/graphite composites were manufactured by adding graphite powders with different particle sizes to mixtures of SiC powder, metallic silicon, carbon black and alumina, effects on the tribological property of each RBSC/graphite composite was investigated in accordance with the particle size of the added graphite powder. The water absorption, the bending strength and the resistance for the friction and wear were measured, and the crystalline phase and the microstructure were respectively examined by using XRD and SEM. In case that the particle size of the graphite powder was fine(2${\mu}{\textrm}{m}$), the formation of $\beta$-SiC was accelerated, thereby making the increase of the bending strength and the decrease of the water absorption, but no improvement for the tribological properties. Furthermore, in case that the particle size of the graphite powder was some large(88~149${\mu}{\textrm}{m}$), the formation of $\beta$-SiC was not accelerated, to thereby make the decrease of the bending strength and the increase of the water absorption, but the improvement for the tribological property of only the composite having the graphite powder of 20 vol%. In addition, in case that the particle size distribution of the graphite powder was large (under 53 ${\mu}{\textrm}{m}$), there was no improvement for every properties. However, the composites, which the graphite powder with the particle size of 53~88 ${\mu}{\textrm}{m}$ was added in 10~15 vol%, had the most increased resistance for the friction and wear which show the worn out amount of 0.4~0.6$\times$10-3 $\textrm{cm}^2$, and the value of the bending strength is 380~520 kg/$\textrm{cm}^2$.

• Toxicological Research
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• 제13권3호
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• pp.297-301
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• 1997

In order to evaluate the mutagenic potential of CJ-50001 (recombinant human granulocytecolony stimulating factor), 3 sets of mutagenicity tests were performed. In the reverse mutation test using Salmonella typhimurium TA1535, TA1537, TA98 and TA100, CJ-50001 did not increase the number of revertant at any of the concentration tested in this study (500, 250, 125, 62.5 and 31.3 $\mu\textrm{g}$ plate). CJ-50001, at the doses of 200, 100 and 50 $\mu\textrm{g}$ /ml, did not increase the number of cells having structural or numerical chromosome aberration in cytogenetic test using Chinese Hamster Lung cells. In mouse micronucleus test, no significant increase in the occurrence of micronucleated polychromatic erythrocytes was observed in ICR male mice intraperitoneally administered with CJ-50001 at the doses of 5, 2.5 and 1.25 mg/kg. These results indicate that CJ-50001 has no mutagenic potential in these in vitro and in vivo systems.

• 한국자원식물학회지
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• 제14권3호
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• pp.220-228
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• 2001

한국에서 자라고 있는 옻나무속 3종의 항산화력을 조사하여 본 결과, 옻나무속 3종의 각 부위별 ethyl acetate 추출물에 대한 항산화능은 개옻나무의 경우 잎과 줄기에서 각각 32, 34 $\mu\textrm{g}$/$m\ell$, 옻나무의 경우 잎과 줄기에서 각각 39,21 $\mu\textrm{g}$/$m\ell$의 활성을 나타내었다. Sephadex LH-20 column chromatography를 이용하여 줄기 부위의 추출물을 12개의 fraction으로 분리하여 항산화능을 측정한 결과, fraction No.3이 가장 높은 항산화 활성을 나타내었으며, 옻나무가 1.5, 붉나무가 1.9, 개옻나무가 2.3 ug/$m\ell$ DPPH가를 나타내었다. 줄기 추출물로부터 2-propenoic acid (Caffeic acid), Benzoic acid (Gallic acid), 7-hydroxy-6- methoxy-2H-1-Benzopyran-2-one (Scopoletin) 등과 같은 phenol계 물질들이 동정되었다. 옻나무속 3종의 부위별 POD 활성 은 잎에 비해 줄기에서 193배 활성이 높게 나타났고 종간에는 붉나무가 0.58 unit/mg protein로 가장 높게 나타났으며 옻나무, 개옻나무 순으로 높게 나타났다. SOD 활성은 옻나무와 붉나무의 잎에 비해 줄기에서 높은 활성이 나타났으나,개옻나무는 잎이 줄기에 비해 25배 높게 나타났다.