• Title/Summary/Keyword: Activity Alkali Activation

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Research for the production of blast furnace cement mortar using an alkaline activation method (알칼리 활성화 방법에 따른 고로슬래그 경화체 제조 연구)

  • Shin, Jae-Ran;Lee, Ju-Yeol;Park, Byung-Hyun
    • Journal of Korean Society of Water and Wastewater
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    • v.30 no.3
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    • pp.293-297
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    • 2016
  • This study was performed in order to obtain the effect of the compressive strength of the cured product with manufacturing conditions (amounts of fine aggregate and different types of alkali activator). Material which is the basis of the cured product was used for the blast furnace slag, which has a latent hydraulic activity. Consequently, when using sodium hydroxide as the alkali activator, it is possible to obtain a higher compressive strength than using the calcium hydroxide. And also, it can be added a 10% of fine aggregate with blast furnace slag to improve the compressive strength.

A Study on the Reaction Kinetics of Nitrogen Compounds over Bimetallic Molybdenum Catalysts (이금속성 형태 몰리브덴 촉매를 이용한 질소화합물의 반응속도 연구)

  • Ahn, Beom-Shu
    • Journal of the Korean Applied Science and Technology
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    • v.22 no.4
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    • pp.349-354
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    • 2005
  • It is interesting to discover the reaction kinetics of the newly developed molybdenum containing catalysts. The dissociation/adsorption of nitrogen on molybdenum surface is known to be structure sensitive, which is similar to that of nitrogen on iron surface. The rates over molybdenum nitride catalysts are increased with the increase of total pressure. This tendency is the same as that for iron catalyst, but is quite different from that for ruthenium catalyst. The activation energies of the molybdenum nitride catalysts are almost on the same level, although the activity is changed by the addition of the second component. The reaction rate is expressed as a function of the concentration of reactants and products. The surface nature of $CO_3Mo_3N$ is drastically changed by the addition of alkali, changing the main adsorbed species from $NH_2$ to NH on the surface. The strength of $NH_x$ adsorption is found to be changed by alkali dopping.

The Effect on the Kind of Alkali-Activator of Cement ZERO Mortar (알칼리 활성화제 종류가 시멘트 ZERO 모르타르에 미치는 영향)

  • Ryu, Gum-Sung;Kang, Hyun-Jin;Ko, Kyung-Taek;Kang, Su-Tae;Kim, Sung-Wook;Lee, Jang-Hwa
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.397-398
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    • 2009
  • Recently, the research about alkaline activity concrete is being progressed actively. In this paper, the effect of many kinds of alkaline activation to fly ash based cement zero mortar is examined.

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Experimental study on chemical activation of recycled powder as a cementitious material in mine paste backfilling

  • Liu, Yin;Lu, Chang;Zhang, Haoqiang;Li, Jinping
    • Environmental Engineering Research
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    • v.21 no.4
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    • pp.341-349
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    • 2016
  • To improve the utilization rate of construction waste as mine backfilling materials, this paper investigated the feasibility of using recycled powder as mine paste backfilling cementitious material, and studied the pozzolanic activity of recycled construction waste powder. In this study, alkali-calcium-sulfur served as the activation principle and an orthogonal test plan was performed to analyze the impact of the early strength agent, quick lime, and gypsum on the pozzolanic activity of the recycled powder. Our results indicated that in descending order, early strength agent > quick lime > gypsum affected the strength of the backfilling paste with recycled powder as a cementitious material during early phases. The strength during late phases was affected by, in descending order, quick lime > gypsum > early strength agent. Using setting time and early compressive strength as an analysis index as well as an extreme difference analysis, it was found that the optimal ratio of recycled powder cementitious material for mine paste backfilling was recycled powder:quick lime:gypsum:early strength agent at 78%:10%:8%:4%. X-ray diffraction analysis and scanning electron microscope were used to show that the hydration products of recycled powder cementitious material at the initial stages were mainly CH and ettringite. As hydration time increased, more and more recycled powder was activated. It mainly became calcium silicate hydrate, calcium aluminate hydrate, etc. In summary, recycled powder exhibited potential pozzolanic activities. When activated, it could replace cementitious materials to be used in mine backfill.

Correlation between Anticomplementary and Antitumor Activity of the Crude Polysaccaride from Ganoderma Iucidum IY009 (Ganoderma lucidum IY 009조다당 분획들의 항암활성과 항보체활성간의 상호관계)

  • Lee, Kweon-Haeng;Lee, June-Woo;Han, Man-Deuk;Jeong, Hoon;Kim, Young-Il;Oh, Doo-Whan
    • Microbiology and Biotechnology Letters
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    • v.22 no.1
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    • pp.45-51
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    • 1994
  • Antitumor polysaccharides were known to activate complement system and to increase specific serum proteins in mouse, and researcher reported that antitumor activity of polyasccharides might be correlated with their biological properties such as activation of complement system and increase of specific protein $L_{A}$, $L_{B}$ and $L_{C}$ within the mouse serum. In case of several Ganoderma lucidum, there was no correlation between their antitumor activities and their bioloical properties, but the antitumor activities against sarcoma 180 of the alkali extracted crude polysaccharide fractions of the Ganoderma lucidum IY 009. AS, T, AI and M were correlated with their bioloical properties such as anticomplementary activity and intensity of mouse serum protein $L_{A}$, $L_{B}$ and $L_{C}$.

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(1) Studies on the Determination of the Rate Control Steps in the Various Metabolic Cycles (I) - The Affect of the Light to the Enzyme Activities in the Cotyledons of the Germinating Seeds - (대사과정(代謝過程)에 있어서 율속단계(律速段階) 결정(決定)에 관(關)한 연구(硏究) (I) - 발아종자자엽(發芽種子子葉)에 있어서 산소활성(酸素活性)에 미치는 광선(光線)의 영향(影響) -)

  • Sin, Gwi-Nam
    • Applied Biological Chemistry
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    • v.3
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    • pp.1-7
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    • 1962
  • In order to study the rate control step in the protein metabolic course of the chlorophyll formation, the transaminase activities which are obtained freely in the extracts of cotyledons of germinating peas at the light and the dark places, are measured in Beckman mopel D.U, spectrophoto meter at 490 mu. In this case, of two enzymatic reaction products; oxalacetic acid and pyruvic acid, the former is converted to pyruvic acid by aniline citrate and after each pyruvate phenyl hydrazones are extracted by toluenes: when this is treated with strong alcoholic alkali, a colored hydrazone is formed and it is measured by above apparatus. The estimated G.O.T. and G.P.T. in the germinated cotyledons at dark and light places considerably differ in their activities; G.O.T. and G.P.T. activities which are formed at the light are more increased than at the dark and also they differ in their rates through germination, though G.O.T. activity increment is smoothly but that of G.P.T. is more sharply, and they are considered to be directly affected to the chlorophyll formation and indirectly to the growth. G.O.T. and G.P.T. in each fractions of cell in the cotyledons should be formed by dissociation of zymogens in the microsomal fractions and it seems to promoted by light. In the formation of the chlorophyll, the protein metabolism occurred mainly in the microsomal fractions and the rate determining step is found at the point where the zymogene that is able to produce G.P.T. is activated, and this activation is promoted by light as noted above.

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