• Title/Summary/Keyword: Elevated temperature condition

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Application Study of Skin Beauty Culture, Green Laver Culture and Synthesis of ${\alpha}$-Chloro Substituted Chitosan Succinic Acid Derivatives (${\alpha}$-Chloro 치환기를 갖는 Chitosan Succinic Acid 유도체 합성 및 피부미용과 해태 김 양식 응용 연구)

  • Ryu, Soung-Ryual
    • Journal of Integrative Natural Science
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    • v.4 no.4
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    • pp.323-331
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    • 2011
  • In this study, ${\alpha}$-chlorosuccinic acid was synthesized through the reaction of maleic anhydride with HCl(g), (UV)250 nm~300 nm wavelength in presence of $CCl_4$. For the second reaction of N-(monochloro)succinic acid contained glucosamine derivatives(I) was accomplished by a modification of the general acylation using excess ${\alpha}$-chlorosuccinic anhydride in the presence of 2% acetic acid with methanol condition as a solvent at elevated temperature($70^{\circ}C$). We considered organic acid derivatives were useful especially for treatment for the cultivating porphyra.

Electrodeposition of Zr on AISI 304 Stainless Steel in Molten Chlorides. (염화물계 혼합염욕중에서 AISI 304 Srainless Steel의 Zr 전해피복에 관한연구)

  • 반장호;백영현
    • Journal of the Korean institute of surface engineering
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    • v.30 no.3
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    • pp.159-166
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    • 1997
  • The metalliding technique was adopted to obtain the diffusion coating of zirconium on AISI 304 Stainless Steel in molten mixed chlorides (32.9wt.%LICl-34.8wt.%NaCl-32.3wt.%). Experiments were carried out in argon gas atmosphere. The electrolytic cell was consisted of a AISI 304 Stainless steel cathode and a consumable zirconium anode. The quality of deposit was analysed by SEM, Optical Microscope, EDS, and also examined by the Micro-Vickers hardness and corrosion tests. Interface of deposit layer was identified as zirconium-iron alloy layer caused by diffusion process at elevated temperatures. The optimum condition for the metalliding was found to be the bath temperature of $550^{\circ}C$, the concentration of $K_2ZrF_6$ ,5wt.%, cathodic current derrent density of 7.0 to 10.0mA/$\textrm{cm}^2$ , and anodic current density of 2.0mA/$\textrm{cm}^2$.

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Investigation of Spalling Mechanism in High Performance Concrete Subjected to Fire (고성능 콘크리트의 화재시 폭렬성상에 관한 메카니즘 고찰)

  • Han, Min-Cheol;Kim, Seong-Hwan;Park, Yong-Kyu;Heo, Young-Sun;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.11a
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    • pp.99-102
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    • 2006
  • This paper reviews the relevant literatures and investigates spalling mechanism of high strength concrete, in order to clearly inform spalling problem in fire. Firstly, we studies literatures on spalling occurrence and resistance methods. Secondly chemical change of concrete components in elevated temperature was presented. Finally, mechanism of the spalling occurrence and spalling resistance were carried out with fiber content. In addition, our research team introduced spalling mechanism, being different from other points of view, which has been generally accepted. To secure this mechanism theory, we investigate spalling properties of certain specimens fabricated by roller spindle and made with mortar or concrete condition.

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Development of Translucent RP Material by Post-processing: Case Study of FDM (후가공을 통한 반투명 RP 재료의 개발: FDM의 예)

  • Jeong, Woo-Byok;Lee, Sun-Young;Ahn, Sung-Hoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.9
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    • pp.1524-1530
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    • 2003
  • Translucent plastics are commonly used in packaging of mechanical and/or electrical components. Although Rapid Prototyping(RP) provides prototypes of various materials, translucent RP parts are not readily available from most RP processes. ABSi is one of the ABS materials available for Stratasys' FDM process, and the material had potential to be translucent. In this paper, two post-processing techniques were applied in order to increase optical transmissivity of the parts made of FDM's ABSi. First, elevated temperature condition was applied resulting in increased transmissivity while dimensional shrinkage was observed. Second, resin infiltration and surface sanding provided up tp 16 % transmissivity without shrinkage. These post-processes can be selectively applied to increase transmissivity of ABSi parts. Thus, translucent FDM part can be fabricated from regular FDM process followed by the post-processes developed in this study.

Molecular Dynamics Simulation of Intercalation of Benzopyrene Motif in DNA (핵산의 분자역학적 모의실험을 통한 벤조피렌 층상구조의 발현)

  • Park, Kyung-Lae;Santos, Carlos De Los
    • YAKHAK HOEJI
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    • v.54 no.1
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    • pp.62-66
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    • 2010
  • Benzopyrene is known to be one of the most powerful carcinogens which can build intercalated motif between base pairs in damaged DNA. The dimension of benzopyrene itself is much bigger than any of the DNA bases and thus the question whether the lesion of some base pair by insertion of benzopyrene can happen with or without a dramatic distortion of the helical structure is a highly interesting theme. In this work we used a molecular mechanics simulation using AMBER program package to go into the conformational characteristics. The condition of the insertion process of the benzopyrene motif from minor groove of the starting structure between the base pairs in the internal area of double helix was investigated using the molecular dynamics simulation at elevated temperature.

Pulmonary Blastomycosis in a Monkey (원숭이의 폐장 Blastomycosis 1예)

  • Rim, Byung-Moo;Han, Du-Seok
    • Korean Journal of Veterinary Research
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    • v.23 no.1
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    • pp.91-94
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    • 1983
  • An adult male rhesus monkey (Macaca mulata) developed anorexia, ataxia, dullness, coughing, and some elevated body temperature and died a week after the initiation of such symptoms. At necropsy the monkey's physical condition was found to be normal. Body weight was 18.3kg and the only notable gross lesion was the appearance of acute pneumonia with multiple nodules. Histopathologic observation of the tissues obtained from this animal revealed the features of acute primary pulmonary blastomycosis.

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Effect of Corrosion Conditions on the Luster Change of Metallic Yarns and Fabric - Analysis of Changes in Reflection and Transmission -

  • Shin, Hye-Sun;Kim, Jong-Jun;Jeon, Dong-Won
    • Journal of Fashion Business
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    • v.12 no.3
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    • pp.54-61
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    • 2008
  • The glitter of lame fabrics containing the metallic yarns may further be altered by $Na_2CO_3$ aqueous solution at an elevated temperature. In this study, the effect of the corrosion treatment on the yarn luster was evaluated using image analysis. The alkaline solution treatment was found to be more effective on the aluminum-based specimens than on the silver-based specimens. It was found that corrosion percentage measurement based on the transmission analysis may provide reasonable quantitative index, even if the measurement relies on an indirect method. Based on the quantitative results, the alkaline treatment condition for the specific specimen would be optimized for a desired glitter modification.

Differently expressed genes of soybean by ambient heat stress

  • Jung, Inuk;Kim, Jin Hyeon;Jung, Woosuk
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.156-156
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    • 2017
  • Plants are grown under constitutive changing of environmental conditions and response to external conditions at both protein and transcription level. The effects of heat on plant growth are broad and influence the yield directly. Heat stresses could be classified depend on intensity and duration. Fundamental changes of growth condition by climate change maybe or maybe not classified as a stress on plant growth. The effects of a short and unanticipated impact of elevated heat on plant could be different with those of under longer extension of ambient heat. To examine differently expressed gene sets by ambient heat stress of soybean, we grow the soybean in normal condition for three weeks. After that, soybean plants move to growth chamber. The temperature of growth chamber increase up to $9^{\circ}C$ for four days. We have extracted mRNA and micro RNA every 24 hours and carried RNA sequence analysis. We found major metabolic pathways affected by ambient heat stress. Mainly carbon metabolism, translation machinery and amino acid synthesis are affected. We discussed the expression patterns of genes of heat sensing and hormone responses.

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Study of Ecological Response of Endangered Sarcandra glabra (Thunb.) Nakai according to Moisture and Nutrient under Condition of Climate Change for Propagation and Restoration (증식 및 복원을 위한 기후변화조건에서 수분과 유기물에 따른 멸종위기식물 죽절초(Sarcandra glabra (Thunb.) Nakai)의 생태적 반응 연구)

  • Lee, Soo-In;Lee, Eung-Pill;Jung, Young-Ho;Kim, Eui-Ju;Lee, Jae-Keun;Lee, Seung-Yeon;Park, Jae-Hoon;Lee, Sang-Hun;You, Young-Han
    • Korean Journal of Environment and Ecology
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    • v.32 no.1
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    • pp.30-38
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    • 2018
  • The purpose of this paper is to provide reference data about propagation, restoration, and preparation of policy of endangered Sarcandra glabra (Thunb.) Nakai by investigating growth response and variation of ecological niche breadth according to moisture and nutrient under the condition of elevated $CO_2$ concentration and elevated temperature. We divided the investigation into the controlled group and treated group (elevated $CO_2$ concentration and elevated temperature) and then varied the moisture and nutrient treatment for testing. The results showed that the ecological niche breadth was wide at moisture and nutrient gradients of 0.899 and 0.844, respectively, under control. Also, the ecological niche breadth regarding the moisture and nutrient gradients under treatment simulating global warming was wider as 6.60% and 2.09%, respectively. Therefore, moisture and nutrient will not be the restriction factors concerning the growth of Sarcandra glabra under continued global warming. However, it will be advisable to specify the nutrient content condition in the soil to be 10% for population restoration when growing Sarcandra glabra in the green house which is not affected by external environment since the studies of rearing reaction reported that Sarcandra glabra prefer 10% of nutrient content than 0-5%. Furthermore, it is necessary to protect evergreen broad-leaved forest where is the natural habitat of Sarcandra glabra that has relatively high nutrient content.

Impact of Internal/External Diffusion on Gasification Reaction Rate Analysis of Coal Char in High Temperatures and Elevated pressures (고온/고압 조건에서의 석탄 촤 내부 및 외부 가스화 반응효과)

  • Kim, Gyeong-Min;Kim, Jin-Ho;Lisandy, Kevin Yohanes;Kim, Ryang-Gyoon;Kim, Gyu-Bo;Jeon, Chung-Hwan
    • Journal of the Korean Society of Combustion
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    • v.21 no.4
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    • pp.23-29
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    • 2016
  • Reactivity of gasification defined by bouardard reaction is critical parameter in efficiency of the gasifier. In this study, char reactivity of the gasification was derived from the experiments using the intrinsic reaction kinetics model. Pressurized wire mesh heating reactor (PWMR) can produce high temperature and high pressure conditions up to 50 atm and 1750 K, respectively and PWMR was designed to evaluate the intrinsic reaction kinetics of $CO_2$ gasification. In this study, Kideco and KCH (sub-bituminous Indonesian coal) were pulverized and converted into char. Experiments used the PWMR were conducted and the conditions of the temperature and pressure were 1373~1673 K, 1~40 atm. To distinguish the pressure effect from high pressurized condition, internal and external effectiveness factors were considered. Finally, the intrinsic kinetics of the Kideco and KCH coal char were derived from $n^{th}$ order reaction rate equations.