• 제목/요약/키워드: H3 absorption

검색결과 1,486건 처리시간 0.032초

Pd 박막 시료의 제작 조건이 수소 흡수-방출 동역학에 미치는 영향에 관한 연구 (The effect of Pd film evaporation condition on the kinetics of hydrogen absorption-desorption)

  • 엄대현;유정국;조영신
    • 한국수소및신에너지학회논문집
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    • 제9권3호
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    • pp.127-133
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    • 1998
  • 각각 다른 기판온도에서 진공 증착법으로 제작된 Pd 박막들의(두께 ) 수소 흡수-방출 동역학을 실험하였다. 상, 온도영역에서 수소기체를 흡수-방출 시키면서 정방향과 역방향 활성화에너지를 구하고 반응엔탈피를 구하였다. 기판의 온도가 상온인 시료는 정반응 활성화에너지가 kcal/mol H이고 역방향은 kcal/mol H 반응엔탈피는 -2kcal/mol H였다. 기판의 온도가 인 시료는 정방향 활성화에너지 kcal/mol H 이고 역방향 활성화에너지 kcal/mol H였다. 기판의 온도가 상온인 시료의 구조적 치밀성, 온도변화에 따른 비저항 값의 변화율 등을 측정해 보았을 때 기판의 온도가 상온인 시료에 비하여 더 안정된 상태였지만 활성화 에너지의 오차값이 크게 얻어졌다.

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분리 동백단백의 기능적 특성 (A Study on the Functional Properties of Camellia(Camellia japonica L.) Seed Protein Isolate)

  • 강성구
    • 한국자원식물학회지
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    • 제11권3호
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    • pp.272-278
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    • 1998
  • This study was carried out to investigate the functional properties such as nitrogen solubility, emulsifying property , foaming capapcity , water and oil absorption of Camellia (Camellia japonica .) seed protein isolate in condition of distilled water and 0.5M NaCl solution at pH 2.0∼10.0. Nitrogen solubility of Camellia protein isolate in distilled water showed the minimum value at pH 4.0 and increased at pH lower or higher than the isoelectric point(pH 4.0). It was 90.0 %at pH 10.0 Nitrogen solubility of 0.5M NaCl solution showed a similar pattern with that of distrille dwater but was higher than that of distilled water except pH 2.0 and pH 10.0. Emulsifying activity of Camellia seed protein islate showed the minimum value at pH 4.0, but was higher at ether value of pH. Emulsifying stability of protein isolate was stable by heat treatment for 30min, at 80℃ and increased in 0.5M NaCl solution more than that of distille dwater. Foaming capacity of Camellia seed protein isolate in distill3ed water showed the minimum value near the isoelectric point, While it changed little at other values of pH. Foaming stability slowly decreased as, but didn't make a significant difference as time was delayed . Oil absorption was 1.4ml per a sample of 1g and water absorption was 0.9ml per a sample of 1g. The former was higher than the latter . The content of total amino acid of Camellia protein isolate was 43.67% and the major total amino acid of Camellia protein isolate was 43.67% and the major total amino acid was in the order of glutamic acid , arginine, aspartic acid, and leucine.

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GREEN TEA AND ITS CATECHINS AS DIETARY AND PHARMACOLOGICAL MEANS OF LOWERING CHOLESTEROL ABSORPTION

  • Koo Sung I;Noh Sang K.;Loest Helena B;Wang Shu
    • 한국식품영양과학회:학술대회논문집
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    • 한국식품영양과학회 2001년도 International Symposium on Food,Nutrition and Health for 21st Century
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    • pp.74-87
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    • 2001
  • Evidence shows that the serum level of cholesterol (CH) is decreased with increasing green tea (GT) consumption. This presentation summarizes our recent findings on the effect of GT extract on intestinal absorption of [$^{14}C$-labeled CH and phosphatidylcholine (PC). Ovariectomized (OX) adult rats were infused intraduodenally with lipid emulsions containing radiolabeled lipids [$^{14}C$-CH or $^{14}C$-phosphatidylcholine (PC)] in the presence of GT extract or catechins to determine the rates and amounts of CH absorption and the intestinal hydrolysis and lymphatic output of PC. During lipid infusion, lymph was collected hourly for 8 h. The lymphatic absorption of $^14C$-CH was drastically lowered by infusion of GT extract at two dosage levels (GTl =5.4 mg catechins/h and GT2 = 15.1mg catechins/h). The cumulative lymphatic absorptions of $^{14}C$-CH in rats infused with GT1 and GT2 were 20.7$\pm$4.3 and $4.8{\pm}4.1{\%}$ dose, respectively, whereas the absorption of $^{14}C$-CH in rats infused with no GT extract (GT0) was $36.3{\pm}1.1{\%}$ dose. GT extracts also significantly lowered the absorption of-tocopherol (TP) in a dose dependent manner ($29.6{\pm}4.9{\%}$ dose in GT0, $20.8{\pm}5.8{\%}$ dose in GTl, and $7.9{\pm}5.4{\%}$ dose in GT2 groups). Both (+)-catechin and EGCG significantly lowered the lymphatic outputs of $^{14}C$-radioactivity after intraduodenal $^{14}C$-PC infusion. A significantly higher amount of $^{14}C$-PC remained unhydrolyzed in the intestinal lumen of the EGCG rats ($22.8{\%}$) compared with the (+)-catechin ($15.8\%$) and control groups ($11.9\%$). GT extracts, (+)-catechin, and EGCG significantly reduced the absorption of TP. The inhibitory effect of GT extract and catechins on lipid absorption may be mediated in part through the inhibition of pancreatic PLAz. The findings provide the first direct evidence that green tea and catechins have a profound inhibitory effect on the intestinal absorption of CH in OX rats. Results suggest that green tea and catechins may be used as a dietary or pharmacological means of lowering cholesterol absorption.

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Electrochemical Study for 1,3-Bisdicyanovinylindane

  • Kim, Hyungjoo;Rao, Boddu Ananda;Son, Young-A
    • 한국염색가공학회지
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    • 제25권2호
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    • pp.89-93
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    • 2013
  • The electrochemical study has been enjoyed in many areas of chemistry. Through this approach using electrochemical measurement, empirical HOMO and LUMO values can be calculated by three methods such as absorption measurement, cyclicvoltammetry and computational calculations. In this study, 1,3-bisdicyanovinylindane was prepared and investigated toward its optical properties. The absorption intensities were changed depending on changes of pH. These absorption changes are induced by resonance form of 1,3-bisdicyanovinylindane. The electron delocalization in ${\pi}$ system is related to the resonance form. In according to this electron density distribution and HOMO/LUMO values of 1,3-bisdicyanovinylindane were simulated and calculated by Material Studio 4.3, absorption measurement and cyclicvoltammograms. The 1,3-bisdicyanovinylindane is one of the most attracted acceptor units in D-${\pi}$-A system. This attempt is useful to determine more detailed characteristics of the energy potentials.

암모니아수 흡수제를 이용한 이산화탄소 제거 공정에서 침전생성이 조업영역에 미치는 영향 (Effect of Precipitation on Operation Range of the CO2 Capture Process using Ammonia Water Absorbent)

  • 유정균;박호석;홍원희;박종기;김종남
    • Korean Chemical Engineering Research
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    • 제45권3호
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    • pp.258-263
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    • 2007
  • 배가스 이산화탄소 처리를 위한 화학적 흡수공정의 새로운 흡수제로서 암모니아수의 적용 가능성을 고찰하였다. 이산화탄소 흡수용량과 침전 발생의 관점에서 적합한 암모니아수 흡수제 농도와 $CO_2$ 부하(loading, $molCO_2/molNH_3$)를 결정하였다. 이를 위하여 전해액에 대한 Pitzer 모델을 이용하여 암모니아 흡수제 농도에 따른 흡수용량과 침전 발생여부를 계산하였다. $5\;molNH_3/kgH_2O$ 이상의 암모니아수 흡수제를 사용하여 기존 아민류 흡수제 이상의 흡수용량은 얻을 수 있었다. 각 암모니아 흡수제 농도에서 $NH_4HCO_3$ 침전의 발생으로 인하여 조업이 제약되는 $CO_2$ 부하를 구하였다. $5{\sim}14\;molNH_3/kgH_2O$의 암모니아 흡수제는 293, 313 K에서 $CO_2$ 부하 0.5 이상에서 침전이 발행하였다. 침전 생성 $CO_2$ 부하값 이하로 흡수탑을 조업함으로써 고농도 암모니아 흡수제가 배가스 $CO_2$ 처리 공정에 사용될 수 있음을 알 수 있었다. 흡수용량과 침전발생을 고려하여 배가스 이산화탄소 처리를 위한 흡수제 최적온도는 암모니아수 농도에 따라 297~312 K이었다.

PLANT BIOCHEMISTRY OF GINSENG SAPONINS(II) Radioactives(1) Squalene-$H^3$ Feeding Experiments

  • 고려인삼학회
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1974년도 학술대회지
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    • pp.95-100
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    • 1974
  • The radioactive compound $squalene-H^3$ prepared from peas (Pisum sativum L.) with 5H -mevalonic acid was administered to two- and four-year-old American ginseng (Panax quinquefolium L.) Plants and cuttings in September. The $squalene-H^3$ uptake was low $(40\~86\%).$ $Squalene-H^3$ was not incorporated into the panaquilin sapogenin panaxadiol. This may be due to its poor solubility characteristics and plant absorption, or to the low specific activity. It is possible, but unknown, if any squalene was metabloized into the carbohydrate portion of the panaquilins.

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H2O2 산화제를 이용한 δ-FeOOH의 합성과 입자 크기 제어 (Synthesis and Particle Size Control of δ-FeOOH Using H2O2 Oxidizing Agent)

  • 신성민;김경환;홍정수
    • 한국전기전자재료학회논문지
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    • 제37권3호
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    • pp.292-296
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    • 2024
  • In this study, Iron (III) oxide-hydroxide (δ-FeOOH) was successfully synthesized using hydrogen peroxide (H2O2) as an oxidizing agent. The synthesis of δ-FeOOH was carried out by controlling the amount of H2O2, and pure δ-FeOOH was successfully synthesized in ranges from 0.2 mL to 0.6 mL of H2O2. The size of the synthesized δ-FeOOH particles was compared by controlling the amount of oxidant H2O2. The average particle size of the synthesized pure δ-FeOOH particles increased from 875.1 nm to 897.2 nm as the amount of H2O2 was increased. The optical properties of δ-FeOOH synthesized under these specific conditions were investigated. All δ-FeOOH showed a similar trend of increasing and decreasing light absorption from 800 nm to 400 nm, although there was a slight difference in the amount of light absorption, with the largest amount of light absorption at 410 nm. The band gap energy of δ-FeOOH through the Tauc plot method was about 2.1~2.2 eV when H2O2 was 0.2~1.4mL. With a sufficient small particle size, simple control of that particle size, and a small band gap energy enough to absorb light in the visible spectrum, δ-FeOOH could be useful in a variety of applications, including photoelectrochemistry and battery electrodes.

규칙충전물을 적용한 화학흡수법에 의한 이산화탄소 제거에 관한 연구 (A Study on CO2 Removal by Chemical Absorption Using Structured Packing)

  • 김재홍;김형호;김장호
    • 청정기술
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    • 제9권1호
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    • pp.43-48
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    • 2003
  • As a result of study on factor affecting absorption efficiency using the structured packing, Mellapak N. 250Y for the chemical absorption of $CO_2$ that cause global warming due to development of industry, it is shown that Mellapak N. 250Y has lower pressure drop and superior efficiency of mass transfer than 25mm Pall ring. Also, in the absorption process, it produces high efficiency in the increase of load and concentration of absorption liquid and produces low efficiency in the increase of temperature. In the effect of overall mass transfer coefficient for 15% MEA on the temperature variation of absorbent, when absorbent temperature for 15% MEA varied as 25, 50, $80^{\circ}C$, overall mass transfer coefficients were shown as 0.83, 1.00, $0.90kmol/m^3-h-kPa$.

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격자형 충진물을 이용한 충진탑내 기액상의 역류에 의한 물질전달과 수력학적 동특성 (Mass Transfer and Hydraulic Kinematic Character Using Lattices Packings by Countercurrent Flow of Gas-Liquid Phase in Packing Column)

  • 김장호;하상안
    • 한국해양공학회지
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    • 제2권2호
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    • pp.130-137
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    • 1988
  • This thesis introduced that character of a treatment technique for a mading synthetic resin Hifiow-Ring. The material system of packings make an experiment air$NH_{3}$/air$H_{2}SO_{4}$, $SO_{2}$-air/NaOH, $NH_{3}$-air/$/H_{2}SO_{4}$ under general conditions. Lattices packing compared with conventional packings was proved low pressure loss and high separation efficiency for high loading per trans unit. And an inflow materal tested for absorption and rectification, it made an experiment under a range regular temperature, low energy and small amount of money. That made possible in simple equation, volume material tranfer coefficient$\beta_{L}$ . a by absorption or $\beta_{V}$ .a calculated in all range loading. The peculiarity pressure loss $\Delta\;P/NUT_{ov}$ for Hiflow-ring contributed to a fall cost of energy, a grade number of a vacuum rectification and absorption calculation.

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홍게 가공회수 단백질의 용해도, 유화력 및 안정성 (Solubility, Emulsion Capacity, and Emulsion Stability of Protein Recovered from Red Crab Processing Water)

  • 김용진;신태선;오훈일
    • 한국식품영양학회지
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    • 제9권3호
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    • pp.319-324
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    • 1996
  • The functional properties of protein recovered from red crab (Chitinonecetes opiiie) processing in water (RCP) were examined and compared with those of soybean protein isolate at pH 2~10 in water and NaCl solu5ion. The solubilities of RCP and SPI were miniumu at pH 4, the isoelectric point and increased significantly at lower or higher than pH 4. Solubilities in NaCl solution for both proteins decreased with incr NaCl concentration increase at all pH ranges. Emulsion capacity for both proteins was also minimum at pH 4 and increased as protein concentration increased from 2 to 6%. Emulsion capacity of RCP was higher than these of SPI at pH 6∼10 and all protein concentrations. Emulsion stability showed a similar trend to that of emulsion capacity. RCP had higher oft absorption capacity and lower water absorption capacity than SPI.

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