• 공업화학
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• 제8권4호
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• pp.589-594
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• 1997

화학증착법을 통하여 $650^{\circ}C$의 증착온도와 0.0126Torr의 산소분압인 증착조건에서 원료물질로 $\beta$-diketonates 킬레이트 화합물을 사용하여 Si(111) 및 $SrTiO_3(100)$ 기판에 $YBa_2Cu_3O_y$ 고온 초전도 박막을 제조하였다. $SrTiO_3(100)$기판에서 제조된 박막의 $T_{c,onset}$과 $T_{c.0}$는 각각 91K와 87K로 나타났다. 또한, Si(111)기판에서 제조된 박막의 $T_{c,onset}$은 91K였지만 $T_{c.0}$는 액체질소 비등점(77.3K)에서는 보이지 않았다. $SrTiO_3(100)$에 증착된 초전도 박막은 치밀하고 2차원적으로 배열된 미세구조를 갖고 있는 반면, Si(111)에 증착된 초전도 박막은 상대적으로 기공이 많으며 무질서한 미세구조를 형성하였다.

• Parasites, Hosts and Diseases
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• 제61권2호
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• pp.138-146
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• 2023

Toxoplasma gondii is an intracellular protozoan parasite which can infect most warm-blooded animals and humans. Among the different mouse models, C57BL/6 mice are more susceptible to T. gondii infection compared to BALB/c mice, and this increased susceptibility has been attributed to various factors, including T-cell responses. Dendritic cells (DCs) are the most prominent type of antigen-presenting cells and regulate the host immune response, including the response of T-cells. However, differences in the DC responses of these mouse strains to T. gondii infection have yet to be characterized. In this study, we cultured bone marrow-derived DCs (BMDCs) from BALB/c and C57BL/6 mice. These cells were infected with T. gondii. The activation of the BMDCs was assessed based on the expression of cell surface markers and cytokines. In the BMDCs of both mouse strains, we detected significant increases in the expression of cell surface T-cell co-stimulatory molecules (major histocompatibility complex (MHC) II, CD40, CD80, and CD86) and cytokines (tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-12p40, IL-1β, and IL-10) from 3 h post-T. gondii infection. The expression of MHC II, CD40, CD80, CD86, IFN-γ, IL-12p40, and IL-1β was significantly higher in the T. gondii-infected BMDCs obtained from the C57BL/6 mice than in those from the BALB/c mice. These findings indicate that differences in the activation status of the BMDCs in the BALB/c and C57BL/6 mice may account for their differential susceptibility to T. gondii.

• 대한전자공학회논문지
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• 제16권3호
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• pp.9-18
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• 1979

본 논문에서는 바나디움 주화물을 사용한 새로운 반도체 소자인 C.T.R을 제조하여 그외 전기적 특성을 조사하였다. 그 실험결과는 다음과 같다. (1) 제조될 C.T.R의 저항급변계수 는 3정도였고, (2) 의 값은 환원시간과 급냉시간에 크게 의존하였으며, (3) 의 큰 값을 갖는 C.T.R은 짧은 switching현상을 갖는다.

• 한국진공학회지
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• 제1권2호
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• pp.259-268
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• 1992

냉연강판의 성능은 그 표면 상태에 의해서 많은 영향을 받는다. Temper-color(T/C)층은 tempering 과정 중 형성되는 다양한 색깔의 얇은 산화층으로서, 우 수한 표면 품질을 갖기 위해서는 방지 또는 제어되어져야 한다. T/C 현상을 이해하기 위하 여 여러 가지 표면 분석방법이 동원되었다. 유백색 T/C층의 표면은 1$mu extrm{m}$ 크기의 구형의 미 세구조로 구성되어 있었다. thens과정 중 C, Si, Mn과 Al이 표면으로 농화됨을 알았고, Mn 과 C은 정상시료에서 보다 T/C 시료에서 농화가 심하였다. T/C 시료에서의 산화층 두께는 정상시료의 60-$\AA$ 보다 매우 두꺼웠으나, 발생 정도에 따라 변화하였다. T/C층 내의 각 원소 산화 상태는, Si은 SiO2의 상태로, Mn은 MnO나 MnO2의 상태로 Fe는 극표면층의 Fe2O3 상태를 제외하고는 metallic 상태로 분석되었다.

• 대한기계학회논문집A
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• 제33권10호
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• pp.1065-1073
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• 2009

In this paper, the estimation method of C(t)-integral for combined mechanical and thermal loads is proposed for elastic-plastic-creep material via 3-dimensional FE analyses. Plasticity induced by initial loading makes relaxation rate different from those produced elastically. Moreover, the interactions between mechanical and thermal loads make the relaxation rate different from those produced under mechanical load alone. To quantify C(t)-integral for combined mechanical and thermal loads, the simplified formula are developed by modifying redistribution time in existing work done by Ainsworth et al..

• Journal of Microbiology and Biotechnology
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• 제19권12호
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• pp.1617-1619
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• 2009

Lactobacillus rhamnosus PL60 was tested for whether it can produce c9,t11- and t10,c12-conjugated linoleic acids (CLAs) in human. After consumption of L. rhamnosus PL60, L. rhamnosus was detected in feces 1 week after the start of intake. Analysis by gas chromatography showed that concentrations of c9,t11- and t10,c12-CLAs in serum had increased and concentrations of serum leptin had significantly decreased. Results showed that L. rhamnosus PL60 can survive in human intestines and produce CLAs in humans. This is the first report that bacteria can produce CLAs in humans.

• Journal of Welding and Joining
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• 제18권6호
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• pp.89-95
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• 2000

Creep-fatigue crack growth behavior at the heat affected zone of 1Cr-0.5Mo steel weldment has been experimentally studied. Load hold times of the tests for trapezoidal fatigue waveshapes were varied among 0, 30, 300 and 3,600 seconds. Time-dependent crack growth rates were characterized by the {TEX}$C_{t}${/TEX} estimated with the equation proposed by the previous finite element analysis work. It was concluded that the {TEX}$C_{t}${/TEX} values calculated from the properties of parent metal were quite comparable to the accurate {TEX}$C_{t}${/TEX} values calculated from both of weld and parent metals. Scatter of data was claimed due to the difference of exact location of the cracks in HAZ. The cracks have a tendency to change their path from the original location eventually to the relatively soft HAZ(ie, near-FGHAZ region, fine grained heat affected zone).

• 대한전기학회논문지
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• 제41권5호
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• pp.502-507
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• 1992

To improve temperature stability, 0.05Pb(SnS11/2TSbS11/2T)OS13T-0.35PbTiOS13T-0.60PbZrOS13T+0.4[wt%]MnO S12T piezoelectic ceramics were manufactured with the addition of CrS12TOS13T by Hot Press method. And the SAW delay line was fabricated and effects of CrS12TOS13T to the propagation characteristics of SAW was investigated, and the SAW filter was fabricated on C4 specimen added by 0.2[wt%] CrS12TOS13T whose propagation characteriatics of surface acoustic wave were the bast and its frequency characteristics was investigated. Electromechancal coupling factor(kS1sTS02T) was 3.11[%] and its temperature coefficient of the center frequency(CS1foT)was -21.27[ppm/$^{\circ}C$] in C4. The 31[MHz]]SAW IF filter of C4 scarcely had diffraction phenomena and therefore it was proper.

• 태양에너지
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• 제6권2호
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• pp.3-14
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• 1986

It is desirable to collect the solar thermal energy at relatively high temperature in order to minimize the size of thermal storage system and to enlarge the scope of solar thermal energy utilization. In this study, to develop a solar collector that has both advantages of collecting solar thermal energy at high temperature and fixing conveniently the collector system for long term period, a cylindrical parabolique concentrating solar collector (M.C.P.C.S.C) was designed, which has several rows of parabolique reflectors and thin thickness such as the flat-plate solar collector, maintaining the optical form of concentrating solar collector. The thermal performance of the M.C.P.C.S.C. newly designed in this study was analysed theoretically and experimentally. The results are summarized as follows: 1) prediction equation for outlet temperature, $T_o$, of heat transfer fluid and for the thermal efficiency, ${\eta}$, of the collector were derived as; o $$T_o=[C+B1_n(\frac{I_c(t)}{pv^3})]T_i$$ o $${\eta}=\frac{A}{A_c}\dot{m}[(C-1)+B1_n(E{\cdot}di^6\frac{I_c(t)}{\dot{m}^3})]\frac{T_i}{I_c(t)}$$ 2) When the insolation on the tilted solar collector surface, $I_c$, was $900-950W/m^2$ and the heat transfer fluid was not circulated in tubular absorber, the maximum temperature on the absorber surface was $100-118^{\circ}C$, this result suggested that the heat transfer fluid could be heated up to $98-116^{\circ}C$. The maximum temperature on the absorber surface was decreased with the increase of the collector shape factor, $L_p/L_w$ 3) There was a good agreement between the experimental and theoretical value of solar collector efficiency, ${\eta}$, which was proportional to the collector shape factor, $L_p/L_w$ 4) It is desirable to continue the study on the relationship between the collector shape factor, $L_p/L_w$, and the thermal efficiency of solar collector.

• 한국초지조사료학회지
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• 제36권1호
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• pp.41-49
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• 2016

본 연구는 한우 암소의 임신 단계에 따른 채식 및 반추 행동에 미치는 영향을 규명하기 위하여 실시하였다. 실험에 사용한 공시한우는 미경산 육성우(C), 미경산 임신 3개월령(T1), 미경산 임신 6개월령(T2) 그리고 미경산 임신 9개월령(T3)을 각각 3두씩, 총 12두를 4처리 3반복으로 배치하였다. 그리고 사료급여는 배합사료 체중의 1%, 조사료는 자유 채식시킨 후 육안으로 48시간 행동관찰을 실시하였다. 조사료 섭취량은 T3구(3.68 kg)에서 가장 높았던 반면, C구(1.02 kg)가 가장 낮게 나타났다(p<0.05). 총사료 섭취량은 T3 > T2 > T1 > C구 순으로 높게 나타났다(p<0.05). 또한 체중 대비 건물 채식량 역시 T3 > T2 > T1 > C구 순으로 높게 나타났다(p<0.05). 채식시간, 반추시간 및 저작시간은 유의적으로 T3구에서 높게 나타났으며(p<0.05), 휴식시간은 C구에서 높게 나타났다(p<0.05). 식괴수와 총 저작수는 다른 처리구에 비하여 T3구가 유의적으로 높게 나타났다(p<0.05). 그러나 식괴수 당 반추시간은 처리구들 간에 유의적인 차이를 보이지 않았다. 식괴 당 저작수는 C > T1 > T3 > T2구 순으로 높게 나타났다(p<0.05). 분 당 식괴수는 처리구들 간에 유의적인 차이를 보이지 않았다. 음수 회수 및 배분 회수는 각각 C, T1구에서 유의적으로 높게 나타났다(p<0.05). 그러나 배뇨 회수는 임신기간에 따라 유의적인 차이를 보이지 않았다. 채식율과 저작 효율은 임신기간이 진전됨에 따라 유의적으로 높게(p<0.05) 나타났다. 반추 효율은 T1구가 다른 처리구들에 비하여 높게 나타났다(p<0.05).