• Title/Summary/Keyword: reactive media

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The synthesis and light absorbing properties of heptamethine cyanine chromophores based on benzoxazole derivatives

  • Youn, Hye-Soo;Park, Soo-Youl;Shin, Seung-Rim;Shin, Joung-Il;Oh, Seong-Geun;Jun, Kun
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2008.10a
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    • pp.133-134
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    • 2008
  • A novel near infrared(NIR) absorbing dyes were synthesized by using bis-aldehyde formyl aromatic compounds and heteroaryl derivatives with the reactive methylene group. These dyes provided a range of the NIR wavelength region about 720 nm value. Also, the light absorbing properties of these dyes were investigated in our experiment results. In generally, these NIR colorants may be potential used for optical recording media, DNA sequencing probe and laser beam printings.

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A Study on the Organic Surface in Contemporary Furniture Design (현대가구디자인에서 유기체적 표면에 관한 연구)

  • Suh, Jeong Yeon
    • Journal of the Korea Furniture Society
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    • v.25 no.2
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    • pp.87-95
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    • 2014
  • Since 1990s the concern on essence and inside has transferred onto the surface and its style. The longing for plastic surgery and skin beauty might prove this fervent tendency. Furthermore the development of digital media and technology as well as high-tech material enabled this hope to be real in the realm of design. All these progresses and transitions toward the surface introduced more creative and novel phenomena of furniture design arena around its surface. The rising of surface has evolved through architecture, interior design and furniture. The surface of furniture can be easily transposed into the human skin. And it acquires the aspects of skin's metaphoric and symbolic meaning. The characteristics of skin effect in furniture design can be summarized as material aspects, relational aspects, and formal aspects. Material aspects shows skin's elasticity and smooth plane. Relational aspects express the reactive functions of skin. Formal aspects represent organic power through surface.

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Effect of electron donor for reductive dechlorination of PCE using biobarrier (Biobarrier를 이용한 PCE의 환원적 탈염소화시 전자공여체의 영향)

  • 황보현욱;신원식;김영훈;송동익
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.391-394
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    • 2003
  • The applicability of in situ microbial filter or biobarrier technology for the remediation of soil and groundwater contaminated with chlorinated solvents was investigated. The efficiency and rates of reductive dechlorination of chlorinated solvents are known to be highly dependent on hydrogen concentration. In this study, the effect of electron donors on the reductive dechlorination of PCE was investigated using vermicompost (worm casting) and peat as permeable reactive barrier medium The effect of organic acids (lactate, butyrate and benzoate), yeast extract and vitamin $B_{l2}$ on the reductive dechlorination was investigated. Compared to the control (no electron donor added), addition of electron donors stimulated the dechlorinated rate. Among the electron donor treatments, lactate/benzoate amendment exhibited the highest dechlorination rate. Since vermicompost and peat are inexpensive and biodegradable and have high sorption capacity, they could be successfully used as biobarrier media, especially when electron donors (for example, lactate/benzoate) are added.d.

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Effects of Nitric Oxide Modulating Drugs on Acrosome Reaction in Mouse Spermatozoa

  • Gye, Myung Chan
    • Animal cells and systems
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    • v.4 no.2
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    • pp.151-155
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    • 2000
  • Nitric oxide (NO) is a reactive free radical which plays important roles in animal physiology. To investigate involvement of NO in acrosome reaction (AR), effects of drugs which modulate the intracellular NO level were examined in mouse spermatozoa. N (G)-nitro-L-arginine (L-NA), a potent inhibitor of NO synthesis, decreased AR in a reversible manner, On the other hand, sodium nitroprusside (SNP), an NO generating agent, increased spontaneous AR. Preincubation of sperm in the presence of L-NA potentiated AR after sperm transfer into plain- or SNP-media. Methylene blue, a NO scavenging agent, decreased spontaneous AR. Taken together, it is concluded that NO positively controls AR.

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A Study for Improving the Power Factor of Distribution Transformer using Condenser Control Circuit (콘덴서 제어회로를 이용한 배전용 변압기의 역률 개선에 관한 연구)

  • Lee, Kwang-Jeek
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.28 no.4
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    • pp.21-28
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    • 2014
  • Daily use characteristics of apparent power supplied to distribution transformer can be separated into two different time zone of waking hours and sleeping hours. In sleeping hours, using amount of power is decreasing. The actual curve of power seemed to be quite similar to this kind of separation. Inserting a condenser into a circuit in each different time zone led to maximize power factor of the transformer. The compensating condenser's on/off time is controlled by hysteresis circuit utilizing op amp and power factor of the transformer was improved from 0.945 to 0.999. As a result, the average of current reduction was 2.53A per hour of transformer.

환경적 스트레스에 의한 Helicobacter pylori의 형태 변화

  • 이학성;최태부
    • Microbiology and Biotechnology Letters
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    • v.25 no.3
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    • pp.240-247
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    • 1997
  • Bacillary is the most common form of H. pylori observed during human infection. However, it is known that the morphology change of H. pylori from bacillary to coccoid can be occurred with a response to the environmental stresses such as the nutrient depletion, accumulation of toxic metabolites, pH alteration, and exposure to antimicrobial agents. The coccoid form of H. pylori, which is viable but non-culturable in vitro, seems to be the major cause of antibiotic resistancy and high reinfectability of H. pylori. In this regard, we studied the environmental factors that can induce the morphological change in vitro of H. pylori, and the change of fatty acid composition of plasma membrane. The morphological change from bacillary to coccoid could be observed with the depletion of nutrients, pH variation and reactive oxygen species added in the culture media. This morphologic conversion was paralleled by a dramatic decrease in unsaturated fatty acids and an increase in saturated fattv acids of plasma membrane. The change in composition of membrane fatty acid seems to be a kind of protection mechanism of H. pylori against these environmental stresses.

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Flame Propagation in the Air/Fuel Spray Mixture with Temperature Nonuniformity (비균일 온도분포를 가지는 공기/연료분무 혼합기에서의 화염전파)

  • Kim, Y.M.;Kim, S.J.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.3 no.5
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    • pp.111-121
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    • 1995
  • The initiation and propagation of detonation waves in the air/fuel spray mixture has been numerically analyzed. An improved pressure-based method has been applied to predict the transient heterogeneous reacting flows at all speeds. Numerical results indicate that variations in the temperature gradient, the droplet size, and the fuel vapor concentration have the significant effects on the development of detonation wave in the multi-phase reactive media. The interaction mechanism between the flame-generated pressure wave and the combustion wave is discussed in detail.

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Transfer Characteristics of Porous Metallic Salt-Expanded Graphite Reactive Media (금속염-팽창흑연 다공성 반응매체의 전달특성)

  • 한종훈;김상욱;이건홍
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1999.05a
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    • pp.207-212
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    • 1999
  • 화학반응이 일어나는 고정층 반응기의 성능을 모사하고 해석하기 위해서는 반응베드의 열 및 물질전달 특성을 정확히 아는 것이 중요하다. 본 연구에서는 화학열펌프에 사용되는 금속염-팽창흑연 다공성 반응매체의 유효열전도도와 기체투과도를 측정하였다. 유효열전도도는 전이 일차원 열류기법을 이용하여 측정하였고, 기체투과도는 Darcy's law를 이용하여 측정하였다. 팽창흑연이 함유된 반응베드의 유효열전도도와 기체투과도는 흑연을 기준으로 한 겉보기밀도에 따라 각각 14.1-36.5 W/mK, 8.0x$10^{-15}$-$10^{-12}$ $m^2$의 범위에 있었다.

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Pyruvate Protects Giardia Trophozoites from Cysteine-Ascorbate Deprived Medium Induced Cytotoxicity

  • Raj, Dibyendu;Chowdhury, Punam;Sarkar, Rituparna;Saito-Nakano, Yumiko;Okamoto, Keinosuke;Dutta, Shanta;Nozaki, Tomoyoshi;Ganguly, Sandipan
    • Parasites, Hosts and Diseases
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    • v.56 no.1
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    • pp.1-9
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    • 2018
  • Giardia lamblia, an anaerobic, amitochondriate protozoan parasite causes parasitic infection giardiasis in children and young adults. It produces pyruvate, a major metabolic product for its fermentative metabolism. The current study was undertaken to explore the effects of pyruvate as a physiological antioxidant during oxidative stress in Giardia by cysteine-ascorbate deprivation and further investigation upon the hypothesis that oxidative stress due to metabolism was the reason behind the cytotoxicity. We have estimated intracellular reactive oxygen species generation due to cysteine-ascorbate deprivation in Giardia. In the present study, we have examined the effects of extracellular addition of pyruvate, during oxidative stress generated from cysteine-ascorbate deprivation in culture media on DNA damage in Giardia. The intracellular pyruvate concentrations at several time points were measured in the trophozoites during stress. Trophozoites viability under cysteine-ascorbate deprived (CAD) medium in presence and absence of extracellular pyruvate has also been measured. The exogenous addition of a physiologically relevant concentration of pyruvate to trophozoites suspension was shown to attenuate the rate of ROS generation. We have demonstrated that Giardia protects itself from destructive consequences of ROS by maintaining the intracellular pyruvate concentration. Pyruvate recovers Giardia trophozoites from oxidative stress by decreasing the number of DNA breaks that might favor DNA repair.

The Interactive Virtual Space with Scent Display for Song-Do Tomorrow-City Experience Complex (향 디스플레이가 가능한 송도 Tomorrow-city 체험관의 상호작용 가상공간)

  • Kim, Jeong-Do;Park, Sung-Dae;Lee, Jung-Hwan;Kim, Jung-Ju;Lee, Sang-Goog
    • Journal of the Ergonomics Society of Korea
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    • v.29 no.4
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    • pp.585-593
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    • 2010
  • Recently, we designed an interactive virtual space for the multi-purpose hall in Songdo Future City, located in Incheon, Korea. The goal of the design is to make a virtual space that is flexible and can be adjusted thanks to its unfixed seats in order to accommodate different and unspecified audience sizes. Virtual images are interactively adjusted according to the distance, position and size of audiences, information about which is detected by 9 photo sensors. To increase the sense of immersion, intensity and reality, we utilized the technology of scent display that can create appropriate scents to match the images on the screen. The intensity and persistence of scents were determined by the size, distance and position of audiences. The virtual image contains background images and reactive images. The background images repeatedly project images of spring, summer, autumn and winter. The reactive images consist of small portraits or pictures or icons that define or characterize the season types, and these are added to the background image according to the distance, position and size of the audiences.