• Mycobiology
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• 제45권3호
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• pp.172-177
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• 2017

The genus Paxillus is characterized by the difficulty of species identification, which results in reproducibility problems, as well as the need for large quantities of fungal inoculum. In particular, studies of Paxillus ammoniavirescens have reported divergent results in the in vitro growth while little is known of its capacity to degrade organic matter. For all the above, and assuming that this variability could be due to an inappropriate culture media, the aim of this study was to analyse growth in different culture media (MMN, MS, and 1/2 MS) and in the case of MMN in presence/absence of two types of organic matter (fresh litter and senescence litter) to probe the saprophytic ability of P. ammoniavirescens. We also evaluated the effects of pH changes in the culture media. Growth kinetics was assessed by weekly quantification of the area of growth in solid culture media over 5 wk, calculating the growth curves and inflection points of each culture media. In addition, final biomass after 5 wk in the different culture media was calculated. Results showed that best culture media are MS and 1/2 MS. Moreover, an improvement in growth in culture media containing decomposing fall litter was observed, leading to confirm differences in the culture media of this species with others of the same genus. Further, we established that all growth media suffered a significant acidification after fungal growth.

• 대한기계학회논문집B
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• 제30권8호
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• pp.722-730
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• 2006

In this study, the flow characteristics of a FPN (Fountain Pen Nano-Lithography) using active membrane pumping are investigated. The FPN has integrated chamber, micro channel, and high capacity reservoir for continuous ink feed. The most important aspect in this probe provided control of fluid injection using active membrane pumping in chamber. The flow rates in channel by capillary force are theoretically analyzed, including the control of the mass flow rates by the deflection of the membrane. The above results are compared with the numerical simulations that calculated by commercial code, FLUENT. The velocity of the fluid in micro channel shows linear behaviors. And the mass flows are proportional to the second order function of the pumping pressure that is imposed to the membrane.

• 한국지반공학회논문집
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• 제33권10호
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• pp.25-31
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• 2017

완충재는 고준위폐기물을 처분하기 위한 공학적방벽 시스템에서 중요한 구성요소 중 하나이다. 완충재는 처분공내 사용후핵연료가 담긴 처분용기와 암반사이에 채워지는 물질로써 고준위폐기물의 안전한 처분을 위해 필수적인 요소라고 할 수 있다. 완충재는 지하수 유입으로부터 처분용기를 보호하고, 방사성 핵종 유출을 저지한다. 처분용기로부터 발생하는 고온의 열량은 완충재로 전파되기에 완충재의 열물성은 처분시스템의 안전성 평가에 매우 중요하다고 할 수 있다. 특히, 완충재의 설정온도는 고준위폐기물 처분시설의 설계에 큰 영향을 끼칠 수 있다. 따라서 본 연구에서는 온도변화에 따른 국내 경주산 압축 벤토나이트 완충재에 대한 열물성을 규명하고자 하였다. 열선법과 이중 탐침법을 이용하여 온도변화에 따른 압축 벤토나이트 완충재의 열전도도와 비열을 측정하였다. $22^{\circ}C$와 $110^{\circ}C$ 구간에서는 온도 증가에 따라 포화도가 변화되기에 열전도도와 비열은 급격하게 감소하는 경향을 보였으나 $110^{\circ}C$와 $150^{\circ}C$ 사이의 고온 구간에서는 열전도도와 비열의 추가 변화가 거의 발생하지 않았다.

• 한국재료학회지
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• 제17권8호
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• pp.447-451
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• 2007

We investigated the dependence of the various annealing conditions and thickness ($6\sim45nm$) of the Ti-doped $Al_2O_3$ coating on the electrochemical properties and the capacity fading of Ti-doped $Al_2O_3$ coated $LiCoO_2$ films. The Ti-doped-$Al_2O_3$-coating layer and the cathode films were deposited on $Al_2O_3$ plate substrates by RF-magnetron sputter. Microstructural and electrochemical properties of Ti-doped-$Al_2O_3$-coated $LiCoO_2$ films were investigated by transmission electron microscopy (TEM) and a dc four-point probe method, respectively. The cycling performance of Ti-doped $Al_2O_3$ coated $LiCoO_2$ film was improved at higher cut-off voltage. But it has different electrochemical properties with various annealing conditions. They were related on the microstructure, surface morphology and the interface condition. Suppression of Li-ion migration is dominant at the coating thickness >24.nm during charge/discharge processes. It is due to the electrochemically passive nature of the Ti-doped $Al_2O_3$ films. The sample be made up of Ti-doped $Al_2O_3$ coated on annealed $LiCoO_2$ film with additional annealing at $400^{\circ}C$ had good adhesion between coating layer and cathode films. This sample showed the best capacity retention of $\sim92%$ with a charge cut off of 4.5 V after 50 cycles. The Ti-doped $Al_2O_3$ film was an amorphous phase and it has a higher electrical conductivity than that of the $Al_2O_3$ film. Therefore, the Ti-doped $Al_2O_3$ coated improved the cycle performance and the capacity retention at high voltage (4.5 V) of $LiCoO_2$ films.

• Journal of Ginseng Research
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• 제41권2호
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• pp.169-179
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• 2017

Background: Ginsenosides are the main pharmacological components of Panax ginseng root, which are thought to be primarily responsible for the suppressing effect on oxidative stress. Methods: 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and oxygen radical absorption capacity were applied to evaluate the antioxidant activities of the ginsenosides. Human embryonic kidney 293 (HEK-293) cells were incubated with ginsenosides extracted by pulsed electric field (PEF) and solvent cold soak extraction (SCSE) for 24 h and then the injury was induced by $40{\mu}M$ $H_2O_2$. The cell viability and surface morphology of HEK-293 cells were studied using MTS assay and scanning electron microscopy, respectively. Dichloro-dihydro-fluorescein diacetate fluorescent probe assay was used to measure the level of intracellular reactive oxygen species. The intracellular antioxidant activities of ginsenosides were evaluated by cellular antioxidant activity assay in HepG2 cells. Results: The PEF extracts displayed the higher 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and stronger oxygen radical absorption capacity (with an oxygen radical absorption capacity value of $14.48{\pm}4.04{\mu}M\;TE\;per\;{\mu}g/mL$). The HEK-293 cell model also suggested that the protective effect of PEF extracts was dose-dependently greater than SCSE extracts. Dichloro-dihydro-fluorescein diacetate assay further proved that PEF extracts are more active (8% higher than SCSE extracts) in reducing intracellular reactive oxygen species accumulation. In addition, scanning electron microscopy images showed that the HEK-293 cells, which were treated with PEF extracts, maintained more intact surface morphology. Cellular antioxidant activity values indicated that ginsenosides extracted by PEF had stronger cellular antioxidant activity than SCSE ginsenosides extracts. Conclusion: The present study demonstrated the antioxidative effect of ginsenosides extracted by PEF in vitro. Furthermore, rather than SCSE, PEF may be more useful as an alternative extraction technique for the extraction of ginsenosides with enhanced antioxidant activity.

• 한국환경농학회지
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• 제8권2호
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• pp.142-147
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• 1989

환기에 의한 열손실과 지중으로의 열손실을 제외하면 그린하우스의 열손실은 피복재를 통한 열전도 및 열복사에 의해 일어난다. 따라서 동일한 환경조건 하에서 프라스틱 필름으로 하우스를 만들 때 하우스의 보온력은 피복재를 통한 열손실 속도의 크기에 지배받는다. 본 연구에서는 프라스틱 필름을 통한 상대적 열손실 속도를 측정함으로써 하우스의 보온력을 예측할 수 있는 간단한 장치와 방법을 고안하였다. 육면체 형태의 frame을 만들어 측정용 필름으로 둘러싸서 밀폐된 box를 만들고 thermostat로 조절되는 heater와 box 내부의 온도변화를 감지 기록하기 위한 온도 Probe를 내부에 장치하였다. box 내부와 외부간에 일정한 온도차를 이루게 한 다음 (10$^{\circ}C$내외), 그 온도 차이가 유지되도록 일정한 양의 열을 10회에 걸쳐 단속적으로 (그리고 자동적으로) 투입함에 있어서 그 투입 에 요한 총 시간, 즉 항온유지시간을 재고, 이 항온유지 시간의 역수로서 필름을 통한 상대적 열손실 속도를 측정하였다. 동일한 두께의 필름인 경우에 상대적 열손실 속도는 PE>EVA>PVC의 순으로 감소하였고, silica gel보온재가 첨가된 필름의 열손실 속도는 보온재 무첨가 필름보다 역시 감소함을 보여주었다. 이러한 측정결과는 재질에 따른 필름 보온성에 관한 이미 상식화한 사실과 부합되는 것으로서, 본 고안 장치가 여러 가지 상품화된 하우스용 필름의 선별에 쉽게 이용될 수 있음을 시사한다.

• 한국지반공학회논문집
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• 제29권3호
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• pp.51-60
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• 2013

말뚝 시공 시 선단 부분에 쌓이는 슬라임은 현장타설말뚝의 선단지지력을 감소시켜 구조물의 안정성에 큰 영향을 미친다. 슬라임의 존재 유무는 주로 다짐추 혹은 철근을 낙하시켜 판정하고 있으며, 이와 같은 방법은 주관적인 판단결과로 신뢰성에 한계가 있다. 본 논문에서는 물리탐사기법 중 하나인 전기비저항 특성을 활용하여 슬라임층의 존재 여부와 두께를 과학적이고 객관적으로 평가하는 방법을 제시하고자 한다. 슬라임층의 전기비저항 특성을 평가하기 위하여 기존에 개발된 온도보상형 전기비저항 프로브(TRP)를 활용하였으며, TRP의 형상은 원뿔형태로 직경은 표준콘 관입실험 장비와 동일하게 35.7mm이다. 현장타설말뚝 공법 중 P.R.D(Percusion Rotary Drill) 방법을 적용하고 있는 현장에서 실험을 수행하였으며 전기비저항의 결과를 이용하여 슬라임층의 두께를 평가하였다. 신뢰성 높은 분석을 도모하고자 현장 슬라임층을 이용하여 케이싱 효과, 시간경과 그리고 상대밀도에 따른 실내 실험도 추가적으로 수행하였다. 본 연구에서는 전기비저항을 이용하여 슬라임층 두께를 산정하는 방법이 합리적임을 보여주며, 추후 다양한 지층과 말뚝 시공 공법에 적용성이 기대된다.

• 기술혁신학회지
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• 제17권3호
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• pp.490-518
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• 2014

본 연구는 전자부품연구원과 반도체 테스트용 프로브카드 회사간 기술이전 사례를 중심으로 기술이전이 사업화 성과까지 연계되기 위해 필요한 요인들을 분석하였다. 이러한 연구를 통해 실제 현장에서 가장 영향력 있는 기술이전의 성공요인을 살펴보고 정부정책과 기업전략 측면에서 기술이전과 기술사업화 성과를 창출하는 것을 주요 목적으로 한다. 국내외 선행연구 분석, 프레임워크 설정, 사례분석의 과정을 거쳐 기술 수요자, 기술 공급자, 이전 기술, 기술이전 과정 특성의 4가지 측면에서 시사점을 도출하였다. 연구결과 기술 수요자 특성은 신기술 이전획득전략 및 추진의지/보완 자산과 흡수 능력, 기술 공급자 특성은 기술이전 및 사업화 경험/기술이전과 연계한 사업화 지원의지/풍부한 이전 대상 기술군, 이전 기술 특성은 연구개발단계 및 기술분야/기존 기술과의 연계성, 기술이전 과정 특성은 기술이전 전담조직의 지원활동/기술 이전과정의 적극적 참여 등이 성공요인으로 도출되었다.

• 한국축산식품학회지
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• 제40권4호
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• pp.551-562
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• 2020

Beef fat was replaced with cold press pumpkin seed oil (PSO; 0%, 5%, 15%, and 20%) in the production of bologna-type sausages. A value of pH, water-holding capacity (WHC), jelly-fat separation, emulsion stability and viscosity values were determined in meat batters. Thiobarbituric acid reactive substances (TBARS), color, and textural characteristics (TPA, shear test, penetration test) were determined in end-product at 1, 7, 14, 21, and 28 days of storage at 4℃. The pH values were varied between 6.06 and 6.08. With the increase in the level of PSO in meat batters, there was a significant increase in WHC, jelly-fat separation and viscosity values (p<0.05) while a significant decrease in emulsion stability (p<0.05). TBARS values of sausages were found to be significantly higher than in the control group (p<0.05), and this trend continued during storage. Increasing of PSO level were caused a significant increase in L* and b* values while a decrease in a* value (p<0.05). Hardness, adhesiveness and chewiness values were significantly reduced whereas cohesiveness and resilience values increased (p<0.05). Maximum shear force and work of shear was significantly decreased as the level of PSO increased (p<0.05). Hardness, work of penetration and the resistance during the withdrawal of the probe values (penetration tests) increased significantly with the increase in the level of PSO (p<0.05). These results indicate that PSO has potential to be use as a replacement of animal-based fats in the production of bologna-type sausages.

• Asian Pacific Journal of Cancer Prevention
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• 제15권7호
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• pp.3211-3217
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• 2014

Background: The current study investigated the effects of Piper longumine on radio-sensitization of human breast cancer MDA-MB-231 cells and underlying mechanisms. Materials and Methods: Human breast cancer MDA-MB-231 cells were cultured in vitro and those in logarithmic growth phase were selected for experiments divided into four groups: control, X-ray exposed, Piper longumine, and Piper longumine combined with X-rays. Conogenic assays were performed to determine the radio-sensitizing effects. Cell survival curves were fitted by single-hit multi-target model and then the survival fraction (SF), average lethal dose ($D_0$), quasi-threshold dose ($D_q$) and sensitive enhancement ratio (SER) were calculated. Cell apoptosis was analyzed by flow cytometry (FCM). Western blot assays were employed for expression of apoptosis-related proteins (Bc1-2 and Bax) after treatment with Piper longumine and/or X-ray radiation. The intracellular reactive oxygen species (ROS) level was detected by FCM with a DCFH-DA probe. Results: The cloning formation capacity was decreased in the group of piperlongumine plus radiation, which displayed the values of SF2, D0, Dq significantly lower than those of radiation alone group and the sensitive enhancement ratio (SER) of D0 was1.22 and 1.29, respectively. The cell apoptosis rate was increased by the combination treatment of Piper longumine and radiation. Piper longumine increased the radiation-induced intracellular levels of ROS. Compared with the control group and individual group, the combination group demonstrated significantly decreased expression of Bcl-2 with increased Bax. Conclusions: Piper longumine at a non-cytotoxic concentration can enhance the radio-sensitivity of MDA-MB-231cells, which may be related to its regulation of apoptosis-related protein expression and the increase of intracellular ROS level, thus increasing radiation-induced apoptosis.