• Title/Summary/Keyword: foam reaction

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Syngas and Hydrogen Production under concentrated solar radiation : Redox system of $ZrO_2$ nano-structure (고온 태양열을 이용한 합성가스 및 수소 생산 : $ZrO_2$ 나노 구조화에 따른 산화/환원 특성)

  • Jang, Jong-Tak;Lee, Jong-Min;Cho, Eun-Su;Yang, Seung-Chan;Yoon, Ki-June;Han, Gui-Young
    • 한국태양에너지학회:학술대회논문집
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    • 2012.03a
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    • pp.463-469
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    • 2012
  • Solar thermochemical syngas and hydrogen production process bv redox system of metal oxide was performed under direct irradiation of the metal oxide on the SiC ceramic foam device using solar simulator. $CeO_2/ZrO_2$ nanotube has been synthesized by anodic oxidation method. Syngas and hydrogen production process is one of the promising chemical pathway for storage and transportation of solar heat by converting solar energy to chemical energy. The produced syngas had the $H_2/CO$ ratio of 2, which was suitable for methanol synthesis or Fischer-Tropsch synthesis process. After ten cycles of redox reaction, $CeO_2$ was analyzed using XRD pattern and SEM image in order to characterize the physical and chemical change of metal oxide at the high temperature.

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A Study on the Mixed-Food Wastewater Treatment in an Anaerobic Packed Bed Reactor and Sludge Bed Reactor (혐기성 고정상반응기와 슬러지 Bed반응기에서 혼합-식품폐수처리에 관한 연구)

  • 안재동;김재우;장인용
    • Journal of Environmental Health Sciences
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    • v.19 no.4
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    • pp.38-43
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    • 1993
  • The characteristics of food wastewater treatment in an anaerobic packed bed reactor (APBR) with polyurethane as a packing material and sludge bed reactor (ASBR) was studied. The reactor of 9cm-ID, 150cm-height was fed in a continuous mode from bottom of reactor. For the purpose of constant temperature of reactor, water jacket was installed. The used packing materials was polyurethane sponge foam. Methane which was produced by decomposed organics collected at the top of the reactor for using as a fuel. The substrates used were synthetic, mixed and food wastewater. For the acclimatization of microorganisms, mixed wastewater was used. The major analyses were gas production, COD, pH and volatile acids. Based upon the completed works, the results are as follows: When food wastewater was fed the quantity of produced gas was less than that of synthetic wastewater, but food process saw higher methane content than synthetic process. As well as COD removal efficiency of food process reached at about 85%. In aspect of effluent volatile acid, food process showed low concentration of below 500 mg/l, therefore anaerobic reaction stabled. Conclusively food wastewater used can be digested by anaerobic treatment, especially anaerobic packed bed reactor showed 82% of COD removal, 75% of methane content, 10 l of gas production, and anaerobic sludge bed reactor did 79% of COD removal, 75% of methane content, 81 of gas production at 4 kgCOD/m$^3$day, 36$\circ$C.

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Numerical Analysis of Turbulent Combustion and Emissions in an HRSG System (가스터빈 열 회수 증기 발생기의 난류연소 해석과 배기가스 예측 및 검증)

  • Jang, Jihoon;Han, Karam;Park, Hoyoung;Lee, Wook-Ryun;Huh, Kangyul
    • KEPCO Journal on Electric Power and Energy
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    • v.5 no.2
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    • pp.103-111
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    • 2019
  • The combined cycle plant is an integration of gas turbine and steam turbine, combining the advantages of both cycles. It recovers the heat energy from gas turbine exhaust to use it to generate steam. The heat recovery steam generator plays a crucial role in combined cycle plants, providing the link between the gas turbine and the steam turbine. Simulation of the performance of the HRSG is required to study its effect on the entire cycle and system. Computational fluid dynamics has potential to become a useful to validate the performance of the HRSG. In this study a solver has been implemented in the open source code, OpenFOAM, for combustion simulation in the heat recovery steam generator. The solver is based on the steady laminar flamelet model to simulate detailed chemical reaction mechanism. Thereafter, the solver is used for simulation of HRSG system. Three cases with varying fuel injections and gas turbine exhaust gas flow rates were simulated and the results were compared with measurements at the system outlet. Predicted temperature and emissions and those from measurements showed the same trend and in quantitative agreement.

Silencing YY1 Alleviates Ox-LDL-Induced Inflammation and Lipid Accumulation in Macrophages through Regulation of PCSK9/ LDLR Signaling

  • Zhengyao Qian;Jianping Zhao
    • Journal of Microbiology and Biotechnology
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    • v.32 no.11
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    • pp.1406-1415
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    • 2022
  • The formation of macrophage foam cells stimulated by oxidized low-density lipoprotein (ox-LDL) is deemed an important cause of atherosclerosis. Transcription factor Yin Yang 1 (YY1), which is a universally expressed multifunctional protein, is closely related to cell metabolism disorders such as lipid metabolism, sugar metabolism, and bile acid metabolism. However, whether YY1 is involved in macrophage inflammation and lipid accumulation still remains unknown. After mouse macrophage cell line RAW264.7 cells were induced by ox-LDL, YY1 and proprotein convertase subtilisin/kexin type 9 (PCSK9) expressions were found to be increased while low-density lipoprotein receptor (LDLR) expression was lowly expressed. Subsequently, through reverse transcription-quantitative polymerase chain reaction (RT-qPCR), Western blot analysis, Oil Red O staining and cholesterol quantification, it turned out that silencing of YY1 attenuated the inflammatory response and lipid accumulation in RAW264.7 cells caused by ox-LDL. Moreover, results from the JASPAR database, chromatin immunoprecipitation (ChIP) assay, luciferase reporter assay and Western blot analysis suggested that YY1 activated PCSK9 by binding to PCSK9 promoter and modulated the expression of LDLR in the downstream of PCSK9. In addition, the results of functional experiments demonstrated that the inhibitory effects of YY1 interference on ox-LDL-mediated macrophage inflammation and lipid accumulation were reversed by PCSK9 overexpression. To sum up, YY1 depletion inhibited its activation of PCSK9, thereby reducing cellular inflammatory response, cholesterol homeostasis imbalance, and lipid accumulation caused by ox-LDL.

Decision of Optimized Mix Design for Lightweight Foamed Concrete Using Bottom Ash by Statistical Procedure (통계적 방법에 의한 바텀애쉬를 사용한 경량기포 콘크리트의 최적배합 결정)

  • Kim, Jin-Man;Kwak, Eun-Gu;Cho, Sung-Hyun;Kang, Cheol
    • Journal of the Korea Concrete Institute
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    • v.21 no.1
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    • pp.3-11
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    • 2009
  • The increased demand and consumption of coal has intensified problems associated with disposal of solid waste generated in utilization of coal. Major utilization of coal by-products has been in construction-related applications. Since fly ash accounts for the part of the production of utility waste, the majority of scientific investigations have focused on its utilization in a multitude of use, while little attention has been directed to the use of bottom ash. As a consequence of this neglect, a large amount of bottom ash has been stockpiled. However, the need to obtain safe and economical solution for its proper utilization has been more urgent. The study presented herein is designed to ascertain the performance characteristics of bottom ash, as autoclaved lightweight foamed concrete product. The laboratory test results indicated that tobermorite was generated when bottom ash was used as materials for hydro-thermal reaction. According to the analysis of variance, at the fresh state, water ratio affects on flow and slurry density of autoclaved lightweight foamed concrete, but foam ratio influences on slurry density, while, at the hardened state, foam ratio affects on the density of dry and the compressive strength but doesn't affect on flexural and tensile strength. In the results of response surface analysis, to obtain target performance, the most suitable mix condition for lightweight foamed concrete using bottom ash was water ratio of 70$\sim$80% and foaming ratio of 90$\sim$100%.

A Study on Homemaker's Reaction to Ecological Environment in Different Mass-Housing Types (집합주거형태에 따른 생태학적 환경에 대한 주부의 반응 조사 연구)

  • 윤복자
    • Journal of the Korean Home Economics Association
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    • v.19 no.1
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    • pp.19-24
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    • 1981
  • 本 硏究의 目的은 社會科學 分野의 한 槪念인 "機能"을 服飾의 硏究와 또한 그에 關聯있는 分野의 硏究에 應用할 수 있도록 服飾의 機能에 對한 槪念的인 定義를 展開하고 服飾의 分析을 容易하게 하기 爲하여 服飾의 機能을 分類하여 體系化 하는데 있다. 비록 어떤 硏究에 있어서 變人들을 分類하기 爲하여 쓰인 特殊用語나 혹은 그것들의 定義自體는 重要하지 않을지는 모르나 硏究에서 特殊用語나 槪念的인 用語의 定義는 硏究의 資料를 處理하는데 必須的인 것이며 讀者에게 提示될 수 있는 結論을 내리고 그것을 要約 하는데 도움이 되는 것이다. 服飾의 機能을 分析하고 定義를 내리는 方法을 決定함에 있어 本硏究者는 社會科學者들의 硏究에서 얻어진 槪念을 應用하였다. 服飾의 機能이란 어떻게 全體로서의 服飾이나 或은 服飾의 部分들이 人間이 社會組織속에 參與 할 때에 人間을 돕는가를 意味한다. 服飾의 機能을 크게 나누어 (1) 自然環境으로 부터의 保護手段으로서 人間을 돕고 (2) 社會組織속에서 社會的 地位나 個性의 傳達手段으로서 人間을 돕고 만족시키는 것으로 體系化하였다. 비록 自然環境으로부터 個體의 生理的 組織을 保護하는 手段으로서의 服飾의 機能이 있이것이 恒常 主된 機能은 아닐지도 모른다. 오히려 社會的 地位나 個性에 對한 message나 idea를 傳達하는 것이 身體保護의 機能보다 더 重要한 機能일수도 있다. 그러므로 本硏究의 표1에 보이는 分類法을 服飾分析의 硏究에 變因들로 쓸 境遇는 硏究 對象地나 硏究 對象者들의 背景에 따라 또는 時代 혹은 時期에 따라 어떤 變因들은 삭제 될 수도 있을 것이다.수도 있을 것이다.서 가장 많았고, 다음이 Styrol-foam 판 차광구였으며, 관행 해가림구에서는 후행에서의 근중증가정도가 현저히 낮았으나, Styrol-foam 판 및 Polytex 차광구에서는 후행에서도 비교적 근중증가정도가 높았다. 1 수협수에서도 중간친보다 8개나 더 많았다. 7. 국내 육성계통을 화분친으로 공시한 $F_1$의 10a당 수량성은 511조합의 $F_1$중 91%가 다수성 강세를 발현하는데 그 중에서 10a당 450kg이상 560kg나 증수는 조합만도 11조합이 있었다.는 서천백묘, 백천, SS-74185 및 강림 등이 높고 수원8003, 수원8006 및 Hill이 낮았으며 나머지 품종은 중정도였다. 한편 지방함량은 각각 19.8, 19.3 및 19.2%로 파종기간 차가 작았고 품종별로는 수원8003, 수원8006, 동북대, 봉의 및 Williams 등이 높고 서천백일, 강림, 백천, 륙우003, 동산6001, 동산 7003 및 성안 등이 비교적 낮았고 기타 품종은 중정도였으며, 대체로 단백질함량이 높았던 품종들이 지방함량이 낮은 경향이었다. 7. 단백질과 지방함량기간의 상관은 5월 25일 파종에서 고도의 부의 상관(r=-0.5914)이나 6월10일과 6월 25일 상관에서 각각 r=-0.3038과 -0.2975로 부의 상관경향만을 보여 파종기에 따란 상관의 정도가 약간 달랐다. 8. 10a당 종실수량은 6월10일 파종(100%)에 비해 5월 25일 파종에서 104%로 그 착 적었으나, 6월 25일 파종에서는 76%로 만파에 의한 감수정도가 컸다. 품종별 수량은 5월

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Shear Experiment and Simulation Analysis at Bonded Surface of Specimen Tapered Double Cantilever Beam with Expanded Aluminum (발포 알루미늄으로 된 경사진 이중외팔보 시험편의 접착면에서의 전단 실험 및 시뮬레이션 해석)

  • Sun, Hong-Peng;Cheon, Seong S.;Cho, Jae-Ung
    • Composites Research
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    • v.27 no.6
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    • pp.248-253
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    • 2014
  • In this study, tapered double cantilever beam specimens are designed with the variable of angle to investigate the fracture property at the bonded surface of adjoint structure. These specimens are made with four kinds of models as the length of 200 mm and the slanted angles of bonded surfaces on specimens of $6^{\circ}$, $8^{\circ}$, $10^{\circ}$ and $12^{\circ}$. By investigating experiment and analysis result of these specimens, the maximum loads are happened at 120 N, 137 N, 154 N and 171 N respectively in cases of the specimens with slanted angles of $6^{\circ}$, $8^{\circ}$, $10^{\circ}$ and $12^{\circ}$. As the analysis result approach the experimental value, it is confirmed to have no much difference with the values of experiment and analysis. It is thought that the material property can be investigated effectively on shear behavior of the material composed of aluminum foam bonded with adhesive through simulation instead of experiment by applying this study method.

A Study on the Increase of Bearing Capacity of Soft Ground in Shallow Foundation Using High Density Rapid Expansion Material (고밀도 급속 팽창재를 이용한 얕은기초 연약지반의 지내력 증대에 관한 연구)

  • Ro, Euichul;Kim, Daehyeon
    • The Journal of Engineering Geology
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    • v.30 no.2
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    • pp.185-198
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    • 2020
  • High-density rapid expansion material is a method that increases the solid volume of injection materials due to hydration and foam reactions at the same time as spraying. It is an effective method for securing ground stability, restoring subsidence, and loading during construction of structures. In this regard, through the mechanical experiments of injection materials, the stability of the foundation ground of the structure and the effect of increasing the endurance using site construction were analyzed. The results of the experiment showed that the unit weight of soil decreased by 10.5% after injection of the filling material, and the allowable support for the structure was deemed safe, and the subsidence by each section after ground improvement was determined to be safe at 2.28, 1.55 and 0.46 cm, respectively, with an acceptable subsidence of less than 5 cm. After the field test, five inclinometers were installed on the top floor of the target building to measure the displacement of the X and Y axes. As a result of the measurement, no displacement related to the phenomenon of inequality or subsidence cracks of the structure was measured for about 16 months (509 days) after construction. This can be judged to be a sufficient increase in the stability of the ground after the injection of rapid expansion.

QUICK DETERMINATION OF MEAT COLOR, METMYOGLOBIN FORMATION AND LIPID OXIDATION IN BEEF, PORK AND CHICKEN BY NEAR-INFRARED SPECTROSCOPY

  • Mitsumoto, Mitsuru;Sasaki, Keisuke;Murakami, Hitoshi
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1259-1259
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    • 2001
  • Meat becomes brown and rancid during storage in the refrigerator and display in the case. Color changes, metmyoglobin formation and lipid oxidation are the important problems in the transportation / distribution of meat and retail display. The freshness of meat is determined by the sense of vision and smell. Since conventional method determining lipid oxidation is time consuming and destructive (it needs to homogenize meat with reagents, filtrate, time for reaction and read optical density using spectroscopy), more rapid and nondestructive technical tools are desired. The objective of this work was to evaluate near-infrared spectroscopy as an analytical tool for determining meat color, metmyoglobin formation and lipid oxidation. in beef, pork and chicken. Semitendinosus and longissimus thoracis muscles from six beef steers, biceps femoris and longissimus thoracis muscles from twelve LWD crossbred pigs, and superficial pectoral muscles from twenty-four broilers were used. About a 5-cm diameter and 1-cm thick sample (20.0g) was cut from the muscle and placed on plastic foam, over-wrapped with PVC film, and displayed under flourescent lights at 4 degrees C. during 10 days for beef and pork or 4 days for chicken. The spectra was measured by NIR systems Model 5500 Spectrophotometer using fiber optic scan at range of 400 - 1100 nm. Data were recorded at 2 nm intervals and 10 scans / 10 sec were averaged for every sample. Data obtained were saved as log 1/Re, where Re is the reflectance energy, and then mathematically transformed to second derivatives to reduce effects of differences in particle size. $L^{*}$, $a^{*}$ and $b^{*}$, and metmyoglobin formation were determined by conventional spectrophotometer using the integrating sphere unit. 2-Thiobarbituric acid reactive substances (TBARS) were measured for lipid oxidation. A multiple linear regression was used to find the equation which would best fit the data. The number of wavelengths used in the equation was selected based on the fewer number compared to the increasing multiple correlation and Decreasing standard error. (omitted)

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