• Title/Summary/Keyword: Activating agent

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Effects of a Commercial Activating Treatment Agent on Cultured Porphyra yezoensis thalli (양식 방사무늬김, Porphyra yezoensis의 활성처리제 처리 효과)

  • Park, Sung-Woo;Kim, Dae-Hyun
    • Journal of fish pathology
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    • v.26 no.3
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    • pp.275-282
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    • 2013
  • The use of activating treatment agent (formerly acid treatment agent) has been an effective strategy to remove deleterious epibiont organisms such as diatoms and green seaweeds, and it has greatly contributed to increase in Porphyra production. Although many manufacturers supply many kinds of activating treatment agent with different components in these days, no report about their effects on Porphyra culture was found. In this paper, effects of a commercial activating treatment agent were evaluated for practical use in Porphyra culture. No difference was found in dead cell ratios(%) of Porphyra yezoensis thalli between treated and control groups. However, dead cell ratios of Monostroma nitidum thalli were increased from 0~4.6% to 99.0~100% after the treatment. Bathing Porphyra thalli in activating treatment agent resulted in a great decrease in epiphytic bacterial number attached to the thalli from $10^2{\sim}10^{11}$ cells/g to $0{\sim}10^5$ cells/g but did not change the colour of the thalli. These results suggest that bathing Porphyra thalli in activating treatment agent could be a promising strategy to remove green algae, diatoms and bacteria.

Production of Activated Carbon from Waste Walnut Shell Using Phosphoric Acid and Its Adsorption Characteristics for Heavy Metal Ion (인산활성화제에 의한 폐호도껍질을 원료로 한 활성탄제조 및 이의 중금속 이온 흡착특성)

  • Lee Go-Eun;Ahn Ju-Hyun;Kim Dong-Su
    • Resources Recycling
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    • v.12 no.3
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    • pp.13-24
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    • 2003
  • The production characteristics of activated carbon from waste walnut shell have been investigated by taking activation temperature, activation time, amount of activating agent, and kind of activating agent as the major influential factors. The adsorption capacity of the activated carbon which was produced using phosphoric acid as the activating agent increased with activation temperature and showed its greatest value at about $550^{\circ}C$. Yield for activated carbon was observed to decrease continuously as the activation temperature was raised. The optimal activation time for the highest adsorption capacity was found to be about 2 hr, and as the activation time increased the yield for activated carbon was showed to decrease continuously. The increase in the amount of activating agent resulted in the increase of the yield for activated carbon, however, excessive amount of activating agent deteriorated its adsorption capacity reversely. The variations of the microstructure of activated carbon observed by SEM with several influential factors, correlated very well with its changes in the adsorbability with the same factors and the kind of activating agent was found to play an important role in the determination of the adsorption capacity of activated carbon. To investigate the adsorption characteristics of the produced activated carbon, the adsorption reactions of $Cu^{2+}$ ion were examined using the produced activated carbon as the adsorbent. In general, the kinetics of the adsorption of $Cu^{2+}$ ion was observed to follow a 2nd-order reaction and the rate constant for adsorption reaction increased as the initial concentration of adsorbate was diminished. The equilibrium adsorption of $Cu^{2+}$ was explained well with Freundlich model and its adsorption reaction was found to be endothermic. The activation energy for adsorption was calculated to be 13.07 kcal/mol, which implied that the adsorption reaction was very irreversible, and several thermodynamic parameters of adsorption reaction were estimated using van't. Hoff equation and thermodynamic relationships.

Production of Activated Carbon from Woody Fishing Port Wastes Using Sulfuric Acid as Activating Agent (목질(木質) 어항(漁港) 폐기물(廢棄物)을 원료(原料)로 한 황산(黃酸)에 의한 활성탄(活性炭) 제조(製造))

  • Kim, Dong-Su;Lee, Jung-Eun
    • Resources Recycling
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    • v.15 no.2 s.70
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    • pp.50-57
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    • 2006
  • Production of activated carbon from woody fish parking cases has been studied using waste sulfuric acid as an activating agent for the purpose or promoted recycling of woody fishing port wastes. The adsorption capacity of produced activated carbon was observed to increase with activation temperature and reached its maximum at ca. $650^{\circ}C$ under the experimental conditions. However, the adsorption capacity of activated carbon became deteriorated above this temperature due to the thermal degeneration of its structure. Optimal activation time was found to be about 120 minutes and 1:3 weight ratio of raw material and activating agent was appropriate for increased adsorption capacity of activated carbon under the conditions of $550^{\circ}C$ and 60 minutes of activation time. Regarding the effect of the concentration of activating agent on activation, ca. 1.2 M of sulfuric acid was observed to be proper for an optimal activation or raw material. Comparison of the activation power of sulfuric acid with nitric acid showed that sulfuric acid was superior to nitric acid, however, with regard to the yield of activated carbon there was no significant difference between the two activating agents. The degree of dispersion of carbon particles was shown to be relatively high in neutral condition and the produced activated carbon was considered to be effectively employed for the treatment of metal ions in wastewater due to its negative surface charge in aqueous condition.

Design and Implementation of Intelligent Agent System for Pattern Classification

  • Kim, Dae-su;Park, Ji-hoon;Chang, Jae-khun;Na, Guen-sik
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.7
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    • pp.598-602
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    • 2001
  • Recently, due to the widely use of personal computers and internet, many computer users requested intelligent system that can cope with various types of requirements and user-friendly interfaces. Based on this background, researches on the intelligent agent are now activating in various fields. In this paper, we modeled, designed and implemented an intelligent agent system for pattern classification by adopting intelligent agent concepts. We also investigated the pattern classification method by utilizing some pattern classification algorithms for the common data. As a result, we identified that 300 3-dimensional data are applied to three pattern classification algorithms and returned correct results. Our system showed a distinguished user-friendly interface feature by adopting various agents including graphic agent.

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Antibiotic Effects of blood-activating stasis-dispelling medicinals on Vaginal Microorganisms (활혈거어약(活血祛瘀藥)이 질내(膣內) 미생물(微生物)에 미치는 영향(影響))

  • Cho, Jung-Hoon;Jang, Jun-Bok;Lee, Kyung-Sub;Ryoo, Gap-Soon
    • The Journal of Korean Obstetrics and Gynecology
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    • v.19 no.4
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    • pp.17-32
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    • 2006
  • Purpose : The aim of this study is to investigate the antibiotic effects of 14 herbs among blood-activating stasis-dispelling medicinals on vaginal microorganisms. Methods : Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus, Candida albicans, and Gardnerella vaginalis were used for vaginal pathogenic microorganisms. Lactobacillus gasseri, Streptococcus spp. and Escherichia coli HB101 were used for vaginal normal flora. The blood-activating stasis-dispelling medicinals, Mucunae Caulis, Salviae Radix, Persicae Semen, Myrrha, Zedoariae Rhizoma, Achuranthis Radix, Leonuri Herba, Melandrii Herba, Gleditsiae Spina, Lycopi Herba, Scirpi Rhizoma, Caesalpiniae Lignum, Corydlais Tuber and Polygoni Cuspidati Radix were used in this study. In vitro antibiotic activities were observed by optical density and colony test. Results : The optical density and colony test showed that Gleditsiae Spina, Scirpi Rhizoma, Corydlais Tuber, Polygoni Cuspidati Radix and Melandrii Herba of herbs among blood-activating stasis-dispelling medicinals had antimicrobial effect. Gleditsiae Spina had antimicrobial susceptibility and selective toxicity in Gardnerella vaginalis and MRSA. Scirpi Rhizoma had antimicrobial susceptibility and selective toxicity in Staphylococcus aureus and MRSA. Corydlais Tuber had antimicrobial susceptibility and selective toxicity in MRSA. Polygoni Cuspidati Radix had antimicrobial susceptibility and selective toxicity in Gardnerella vaginalis, Staphylococcus aureus and MRSA. Melandrii Herba had antimicrobial susceptibility and selective toxicity in Gardnerella vaginalis. Conclusion : According to the above results, we could suggest that Gleditsiae Spina, Scirpi Rhizoma, Corydlais Tuber, Polygoni Cuspidati Radix and Melandrii Herba of herbs among blood-activating stasis-dispelling medicinals be available to antimicrobial agent of vaginal pathogenic microbial species in vitro.

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Characterization of Activated Carbon from Wood by ZnCl2 (염화아연(ZnCl2) 부활법에 의해 제조한 목재 활성탄의 특성)

  • Kwon, Gu-Joong;Kwon, Sung-Min;Kim, Nam-Hun
    • Journal of Forest and Environmental Science
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    • v.23 no.1
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    • pp.51-55
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    • 2007
  • The effect of ratio between chemical activating agent and raw material in the preparation of activated carbons from wood has been studied. Pinus koraiensis wood and zinc chloride ($ZnCl_2$) were used for materials in this study. Mixtures of wood and zinc chloride were heated under nitrogen flow in the temperature ranging from room-temperature to $600^{\circ}C$ for 1 hr using thermogravimetric technique. During heat treatment, activated carbons with various pore size and specific surface properties were obtained. The maximum BET surface area and total pore volume were $1468m^2/g$ and 1.74 cc/g, respectively, at the mixture ratio of 1 (wood powder) to 5 ($ZnCl_2$). It can be concluded that the differences in the properties of the activated carbons were related significantly with the ratio of chemical activating regent.

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A Study on the Development of Activated Carbons from Sewage Sludge (하수슬러지를 이용한 활성탄 개발에 관한 연구)

  • Lee, Taek-Ryong;Chung, Chan-Kyo;Joe, Young-Cheon
    • Clean Technology
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    • v.15 no.1
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    • pp.31-37
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    • 2009
  • This study deals with the production process of activated carbons from the sewage sludge char by chemical activation reaction. KOH and NaOH were used as activating agents, which react well with carbon. From the experiments, it was found that activated carbons made with KOH treatment had better physicochemical properties in terms of iodine number and BET value than those made with NaOH treatment. It was also found that the optimal deposition ratio of an activating agent to the sewage sludge char was 75 wt% of KOH and 50 wt% of NaOH. Activated carbons were washed out by distilled water after neutralization with 5 M hydrochloric acid solution. The activated carbons that were produced from a sewage sludge char at this optimal conditions have BET surface areas of approximately $600m^2/g$.

A Study on Development of Activated Carbons from Waste Timbers (폐벌목(廢伐木)을 이용(利用)한 활성탄(活性炭) 개발(開發)에 관(關)한 연구(硏究))

  • Kim, Jong-Moon;Chung, Chan-Kyo;Min, Byong-Hoon
    • Resources Recycling
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    • v.17 no.6
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    • pp.68-78
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    • 2008
  • Using a Pinus koraiensis and Pinus rigida which are normally being discarded in South Korea, optimal conditions of producing activated carbons have been studied to recycle as a higher value-added product. This study consists of two processes, the production process of charcoals from waste timbers by low temperature pyrolysis and the production process of activated carbons from the charcoals by chemical activation reaction. This paper deals with the production process of activated carbons from the charcoals by chemical activation reaction. As an alkali has been generally used as an activating agent, KOH and NaOH which react well with a carbon were used in this study. As a result of the experiments, it is confirmed that activated carbons made with KOH treatment had superior values in physicochemical properties to NaOH, showing that there was no remain of KOH at the surface of the charcoals while there was $3{\sim}4%$ of NaOH remaining after the experiments. Thus, it is concluded that KOH reacted more actively with a charcoal than NaOH. Moreover, it was also found that values in physicochemical properties when using a Pinus koraiensis are superior to the ones when using a Pinus rigida. The optimal mixing ratio of an activating agent to a charcoal was 400 wt.%. To improve the physicochemical properties, activated carbons were washed out by distilled water after neutralization with SM hydrochloric acid solution. When activated carbons were produced from a Pinus koraiensis in this optimal conditions, value of BET surface area was found to be approx. $2400\;m^2/g$.

Apigenin Sensitizes Huh-7 Human Hepatocellular Carcinoma Cells to TRAIL-induced Apoptosis

  • Kim, Eun-Young;Kim, An-Keun
    • Biomolecules & Therapeutics
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    • v.20 no.1
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    • pp.62-67
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    • 2012
  • TNF-related apoptosis-inducing ligand (TRAIL) is a promising agent for management of cancer because of its selective cytotoxicity to cancer cells. However, some cancer cells have resistance to TRAIL. Accordingly, novel treatment strategies are required to overcome TRAIL resistance. Here, we examined the synergistic apoptotic effect of apigenin in combination with TRAIL in Huh-7 cells. We found that combined treatment of TRAIL and apigenin markedly inhibited Huh-7 cell growth compared to either agent alone by inducing apoptosis. Combined treatment with apigenin and TRAIL induced chromatin condensation and the cleavage of poly (ADP-ribose) polymerase (PARP). In addition, enhanced apoptosis by TRAIL/apigenin combination was quantified by annexin V/PI flow cytometry analysis. Western blot analysis suggested that apigenin sensitizes cells to TRAIL-induced apoptosis by activating both intrinsic and extrinsic apoptotic pathway-related caspases. The augmented apoptotic effect by TRAIL/apigenin combination was accompanied by triggering mitochondria-dependent signaling pathway, as indicated by Bax/Bcl-2 ratio up-regulation. Our results demonstrate that combination of TRAIL and apigenin facilitates apoptosis in Huh-7 cells.

Preparation of C Doped TiO2 Photocatalyst Activating to Visible Irradiation and Investigation of Its Photocatalytic Activity (유성 볼밀법을 이용한 탄소 도핑 가시광 활성 TiO2 광촉매 제조 및 이의 특성 평가)

  • Yeo, In-Chul;Kang, In-Cheol
    • Journal of Powder Materials
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    • v.17 no.4
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    • pp.281-288
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    • 2010
  • A carbon doped $TiO_2$ (C-$TiO_2$) photocatalyst, which shows good photocatalytic activity to Ultraviolet irradiation and visible irradiation, was successfully prepared by co-grinding of $TiO_2$ with ethanol or Activated Carbon(C), followed by heat treatment at $200^{\circ}C$ in air for 60 min. Ethanol and C were used as a representative agent of liquid and solid for carbon doping. Their influence on improving photocatalytic ability and carbon doping degree was studied with degradation of methyl orange and XPS analysis. The product prepared by co-grinding of $TiO_2$ with Ethanol had Ti-C and C-O chemical bonds and showed higher photocatalytic activity than the product prepared by co-grinding of $TiO_2$ with C, where just C-O chemical bond existed. As a result, mechanochemical route is useful to prepare a carbon doped $TiO_2$ photocatalyst activating to visible irradiation, where the solid-liquid operation is more effective than solid-solid operation to obtain a carbon doped $TiO_2$.