• Title/Summary/Keyword: reaction active energy.

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Degradation of Chlorinated Organic Compounds by Zero Valent Metals and an Electron carrier

  • Kim, Young-Hun
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2001.04a
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    • pp.53-56
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    • 2001
  • The degradation of tetrachloroethene (PCE) and trichloroethene (TCE) by vitamin B$_{12}$, an electron mediator was examined when zero valent metals (ZVMs) were used as built electron donors. Dechlorination of PCE and TCE by iron and zinc in the presence of vitamin B$_{12}$ showed that the zinc and vitamin B$_{12}$ combination greatly enhances the reaction rates for both PCE and TCE, but iron and vitamin B$_{12}$ result in an increase in reactivity only for PCE degradation, not for TCE degradation in comparing with meta]s only. This result indicates vitamin B$_{12}$(I) Is active towards both PCE and TCE degradation while vitamin B$_{12}$(II) is active towards both PCE. Calculated activation energies for the dechlorination of PCE in the presence of Vitamin B$_{12}$ showed that vitamin B$_{12}$ lowered the activation energy about 40-60 kJ/㏖ for the both metals.the both metals.

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Reaction Characteristics of Thermochemical Methane Reforming on Ferrite-Based Metal Oxide Mediums (페라이트계 금속 산화물 매체 상에서 열화학 메탄 개질 반응 특성)

  • Cha, Kwang-Seo;Lee, Dong-Hee;Jo, Won-Jun;Lee, Young-Seak;Kim, Young-Ho
    • Transactions of the Korean hydrogen and new energy society
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    • v.18 no.2
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    • pp.140-150
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    • 2007
  • Thermochemical 2-step methane reforming, involving the reduction of metal oxide with methane to produce syngas and the oxidation of the reduced metal oxide with water to produce pure hydrogen, was investigated on ferrite-based metal oxide mediums. The mediums, CoFZ, CuFZ, or MnFZ, were composed of the mixture of M(M=Co, Cu or Mn)-substituted ferrite as an active component and $ZrO_2$ as a binder, respectively. The WZ medium, composed of the mixture of $WO_3$ and $ZrO_2$, was also prepared to compare. With an addition of $ZrO_2$, the surface area of the mediums was slightly increased and the sintering of active components was greatly suppressed during the reduction. The higher reactivity of the reduced mediums for water splitting was confirmed by the temperature programmed reaction. From the results of the thermochemical 2-step methane reforming, the reactivity of $CH_4$ reduction and water splitting with ferrite-based metal oxide mediums was relatively higher than that with WZ, and the order of reactivity of the mediums was MnFZ>CoFZ>CuFZ>WZ.

A study on the synthesis of a cathode active material precursor from a waste lithium secondary battery (폐리튬이차전지 스크랩 재활용을 통한 양극활물질 전구체 합성 연구)

  • Kim, BoRam;Kim, Dae-Weon;Kim, Tae-heon;Lee, Jae-Won;Jung, Hang-chul;Han, Deokhyun;Jung, Soo-Hoon;Yang, Dae-Hoon
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.32 no.2
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    • pp.61-67
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    • 2022
  • A metal salt solution was prepared from valuable metals (Ni, Co, Mn) recovered from a scrap of waste lithium secondary batteries, and an NCM811 precursor was synthesized from the solution. The effect on precursor formation according to reaction time was confirmed by SEM, PSA, and ICP analysis. Based on the analysis results, the electrochemical properties of the synthesized NCM811 precursor and the commercial NCM811 precursor were investigated. The Galvano charge-discharge cycle, rate performance, and Cycle performance were compared, and as a result, there was no significant difference from commercial precursors.

Chlorophyll a Fluorescence Parameters of Hulled and Hull-less Barley (Hordeum vulgare L.) DH Lines Inoculated with Fusarium culmorum

  • Warzecha, Tomasz;Skrzypek, Edyta;Adamski, Tadeusz;Surma, Maria;Kaczmarek, Zygmunt;Sutkowska, Agnieszka
    • The Plant Pathology Journal
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    • v.35 no.2
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    • pp.112-124
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    • 2019
  • Barley worldwide is affected seriously by Fusarium seedling blight (FSB) and Fusarium head blight (FHB) diseases caused by the Fusarium species. The objective of this study was to facilitate the resistance of hulled and hull-less barley at different growth stages to F. culmorum according to direct parameters: disease rating (DR), fresh weight of leaves and roots, kernel weight per spike, kernel number per spike, plump kernels, and indirect parameters - chlorophyll a fluorescence (CF). Plate assay, greenhouse and field tests were performed on 30 spring barley doubled haploid (DH) lines and their parents infected with Fusarium culmorum. Direct parameters proved that hulled genotypes show less symptoms. Most studied chlorophyll a fluorescence (CF) parameters (apart from DIo/CS - amount of energy dissipated from PSII for laboratory test, TRo/CS - amount of excitation energy trapped in PSII reaction centers, ETo/CS - amount of energy used for electron transport and RC/CS - number of active reaction centres in the state of fully reduced PSII reaction center in field experiment) were significantly affected by F. culmorum infection. In all experiments, hulled genotypes had higher values of CF parameters compared to hull-less ones. Significant correlations were detected between direct and indirect parameters and also between various environments. It was revealed that ABS/CS, TRo/CS, and RC/CS have significant positive correlation in greenhouse test and field experiment. Significant correlations suggest the possibility of applying the CF parameters in selection of barley DH lines resistant to F. culmorum infection.

Effect of Vanadium Loading Amount on Pt/V/TiO2 Catalyst on NH3-SCO Reaction (NH3-SCO 반응에서 Vanadium 담지함량이 Pt/V/TiO2 촉매에 미치는 영향)

  • Kim, Min Su;Kim, Ki Wang;Hong, Sung Chang
    • Applied Chemistry for Engineering
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    • v.33 no.6
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    • pp.594-599
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    • 2022
  • In the study, NH3-SCO (selective catalytic oxidation) reaction activity accodrding to vanadium loading amount were compared when preparing Pt/V/TiO2. Considering both NH3 conversion rate and N2 selectivity, V 2 wt% loading of the catalyst showed the best activity. When the correlation between physical/chemical characteristics and reaction activity was confirmed, it was confirmed that the increase in lattice oxygen and (V3+ + V4+) ratios were active factor. In addition, when the SO2 durability experiment was conducted using the best catalyst, it was confirmed that the influence was insignificant even if the high concentration of SO2 was injected.

An Experimental Study on the Strength Development of Fly-Ash Mortar by Using the Activator and Curing Temperature change. (자극제 사용 및 양생온도 변화에 의한 플라이애쉬 모르타르의 강도발현에 관한 실험적 연구)

  • 배수환;최광윤;정재동;최영화
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.277-280
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    • 2003
  • The purpose of this study is for the active use of the fly ash, which is a by-product of the combustion pulverizes coal thermal power plants, to compensate for the lack of landfill and for conservation of energy, by using fly ash as the supplementary cementitious material, and to prove its possibility as the related products of the cement. First of all, we examined strength development of Micro grinding fly ash by elevating its fineness and using $Na_{2}SO_{4}$ as an activator to elevate pozzolanic reaction of fly ash. Following fly ash replacement ratio and curing temperature we hope to prove its properties to suggest its possibility in the concrete and cement industry. In case of water curing, the more fineness and higher annexing of activator is, the higher strength is, and the higher curing temperature is the more pozzolanic reaction happens.

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항바이러스제가 단백질의 구조적 거동에 미치는 영향에 대한 유한요소법 기반 분석

  • Yun, Gi-Seok;Kim, Jae-Hun
    • Proceeding of EDISON Challenge
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    • 2015.03a
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    • pp.212-216
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    • 2015
  • Oseltamivir, also known as Tamifu, is an inhibitor of neuraminidase protein which plays an essential role in proliferation and replication of influenza virus. Binding to the active site of neuraminidase, the oseltamivir prevents the protein from enzyme reaction. Conformational change of the protein(neuraminidase) should be accompanied by the enzyme reaction, but the drug inhibits the protein to deform. In this study, we examine the influence of oseltamivir on protein's conformational change in the structural and mechanical point of view. Finite element analysis of the protein can be an useful approach to investigate the influence of oseltamivir on the deformation of a protein. We suggest the finite element based protein model, and then perform the linear static analysis with the displacement loading condition based on the first two largest motion which can be obtained from the normal mode analysis. The results show that it takes more energy to change shape of the protein with an oseltamivir attached than the protein without an oseltamivir.

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Kinetic Features of the Cobalt Dihalide/Methylaluminoxane Catalytic System in 1,3-Butadiene Polymerization

  • Nath Dilip Chandra Deb;Fellows Christopher M.;Shiono Takeshi
    • Macromolecular Research
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    • v.14 no.3
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    • pp.338-342
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    • 2006
  • The kinetic features of polymerization with an active site comprising cobalt dihalides ($CoX_2$, where X=Cl, Br, I) activated by methylaluminoxane (MAO) were investigated in 1,3-butadiene polymerization. The catalytic system exhibited the characteristic features of living polymerization. The initiation ($k_i$) and propagation ($k_p$) rate coefficients were estimated using the kinetic model for slow initiation previously reported by Shiono et al. The energy of activation fur the propagation reaction was calculated to be 27-30 $kJmol^{-1}$. The marked changes in reaction rate observed with different halides could be adequately described in terms of variations in the initiation process, with the same Arrhenius curve fitting propagation rate coeffcients estimated from all three halides, suggesting that the halide does not participate in the growing chain end.

Kinetics and Mechanism of the Oxidation of Carbon Monoxide on H$_2$-Reduced NiO-Doped $\alpha$-Fe$_2O_3$

  • Kim, Don;Kim, Keu-Hong;Choi, Jae-Shi
    • Bulletin of the Korean Chemical Society
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    • v.9 no.2
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    • pp.81-84
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    • 1988
  • The CO oxidation was performed on $H_2$-reduced NiO-${\alpha}-Fe_2O_3$ in the temperature range 150-$250^{\circ}C$. The kinetic study and the conductivity measurements indicate the oxidation reaction follows Langmuir-Rideal type process that is uncommon in heterogeneous catalyst$^1$. No active site is found on the catalyst surface for CO adsorption, but an oxygen vacancy adsorbs an oxygen, and this step is rate initiation. The partial orders are half for $O_2$ and first for CO, respectively. Apparent activation energy for over-all reaction is 9.05 kcal/mol.

A Study on the Improvement Characteristics of Bio Active Energy Radiated Fabric in Muscle Fatigue (생체활성에너지 방사 소재의 근육피로도 개선 특성에 관한 연구)

  • Park, Hyo Suk;Park, Eun Ho;Rho, Yong Hwan;Yang, Gwang Wung
    • Textile Coloration and Finishing
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    • v.26 no.3
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    • pp.181-186
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    • 2014
  • This paper surveys improvement characteristics in muscle fatigue with bio-activity material imbedded fabric. For this purpose, the subjects wear the garment which is covered by bio-activity materials all over every day during 2 weeks of experimental period. After 2 weeks period, VAS(Visual Analogue Scale) index evaluation regarding muscle fatigue and pain has been conducted in comparison between before wearing and after so that we can evaluate the effect on muscle fatigue improvement. The effectiveness survey for testing products consists of improvement on krunkle, muscle fatigue and exercise capacity. As a result, 100% of test subject group completes a questionnaire with positive answer as above normal in every question. In addition the preference of testing products is researched in wearing comfort, activity and convenience. And it is marked above normal by 100% of test subject group as well. Moreover any kind of unusual skin reaction has not been detected in safety evaluation. Therefore this testing products is being judged as a beneficent product for improvement on muscle fatigue without any skin irritation.