• Title/Summary/Keyword: surface activation

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Microbial Control of the Tobacco Cutworm, Spodopera litura (Fab.), Using S. litura Nuclea Polyhedrosis Virus. II. Formulation of S. litura Nuclear Polyhdrosis Virus as Viral Insecticides (곤충 핵다각체병바이러스를 이용한 담배거세미나방의 생물적 방제. II. 담배거세미나방 핵다각체병바이러스의 살충제 제제화)

  • 임대준;진병래;최귀문;강석권
    • Korean journal of applied entomology
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    • v.29 no.4
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    • pp.244-251
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    • 1990
  • Three viral insecticides were differently formulated with a nuclear polyhedrosis virus isolated from Spdodoptera litura by addition of feeding attractant, anti-precipitate of polyhedra, spreading agent, and UV-protectants. Sucrose was effective for attraction of larval feeding to increase the mortality and for protection of polyhedra from inactivation by sunlight when added 1% to 5% of sucrose solution to the formulations. Contents of additives to the formulations were 0.5% in polyvinyl alcohol to prohibit the precipitation of polyhedra and 0.1% in Triton X-100 to spread and wet the formulations to the plant. Inactivation of the virus under sunlight was decreased when added 800g of white carbon to 100 L of water in the white carbon formulation and 30% of molasses to the molasses's. In the formulation of white carbon and molasses mixtures, activation of the virus was increased when mixtured 500g of the former with 10% of the latter. Three formulations were persisted their pathogenicity more than 95% of mortality at 3 days p.i. Encapsulation of the polyhedral surface was more distinctively coated with the carbon and showed more effective in the residual effects of the white carbon than others, but the molasses more attractive for larval feeding.

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Characteristics of Isotherm, Kinetic and Thermodynamic Parameters for the Adsorption of Acid Red 66 by Activated Carbon (활성탄에 의한 Acid Red 66의 흡착에 대한 등온선, 동력학 및 열역학적 특성)

  • Lee, Jong-Jib
    • Clean Technology
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    • v.26 no.1
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    • pp.30-38
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    • 2020
  • The kinetic and thermodynamic parameters of Acid Red 66, adsorbed by granular activated carbon, were investigated on areas of initial concentration, contact time, and temperature. The adsorption equilibrium data were applied to Langmuir, Freundlich, Temkin, Redlich-Peterson, and Temkin isotherms. The agreement was found to be the highest in the Freundlich model. From the determined Freundlich separation factor (1/n = 0.125 ~ 0.232), the adsorption of Acid Red 66 by granular activated carbon could be employed as an effective treatment method. Temkin's constant related to adsorption heat (BT = 2.147 ~ 2.562 J mol-1) showed that this process was physical adsorption. From kinetic experiments, the adsorption process followed the pseudo-second order model with good agreement. The results of the intraparticle diffusion equation showed that the inclination of the second straight line representing the intraparticle diffusion was smaller than that of the first straight line representing the boundary layer diffusion. Therefore, it was confirmed that intraparticle diffusion was the rate-controlling step. From thermodynamic experiments, the activation energy was determined as 35.23 kJ mol-1, indicating that the adsorption of Acid Red 66 was physical adsorption. The negative Gibbs free energy change (ΔG = -0.548 ~ -7.802 kJ mol-1) and the positive enthalpy change (ΔH = +109.112 kJ mol-1) indicated the spontaneous and endothermic nature of the adsorption process, respectively. The isosteric heat of adsorption increased with the increase of surface loading, indicating lateral interactions between the adsorbed dye molecules.

Electrochemical Oxidation of Hydrogen at Palladium Electrode (팔라디움 전극에서의 전기화학적 수소산화반응)

  • Oh, M.H.;Paik, C.H.;Cho, B.W.;Yun, K.S.;Min, B.C.;Ju, J.B.;Sohn, T.W.
    • Transactions of the Korean hydrogen and new energy society
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    • v.7 no.1
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    • pp.45-54
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    • 1996
  • Electrochemical oxidation of hydrogen on PdOx and Pd electrodes were investigated in aqueous 30% KOH solution at different temperatures and hydrogen concentrations(partial pressures). Anodic reaction by hydrogen on PdOx electrode was mainly due to the oxidation of adsorbed hydrogen at -0.8V~-0.5V(vs. Hg/HgO). For Pd electrode, the anodic reaction was participated by the adsorbed hydrogen on surface, as well as by the metal hydride formed from direct reaction between Pd and hydrogen at -0.5V~0.0V(vs. Hg/HgO). With the increase of hydrogen concentration the charge transfer resistance decreased and the exchange current increased. The transfer coefficient of PdOx and Pd electrodes were found to be 0.78 and 0.72 respectively, which shows the superior reactivity of Pd electrode. The activation energies of PdOx and Pd electrodes decreased with the increase of overpotential and were found to be 23.9~20.3 kJ/mole and 7.2~3.0kJ/mole, respectively.

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Purification of Recombinant CTP-Conjugated Human prostatic acid phosphatase for activation of Dendritic Cell (수지상세포 활성화를 위한 세포투과 펩타이드가 결합된 재조합 전립성 산성 인산분해효소의 정제)

  • Yi, Ki-Wan;Ryu, Kang
    • KSBB Journal
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    • v.24 no.1
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    • pp.80-88
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    • 2009
  • Human prostatic acid phosphatase (PAP), with comprehensive homology to glandular kallikrein, are representative serum biomarkers of prostate cancer. Dendritic cell (DC), which is the potent antigen-presenting cells(APC) in the immune system, can induce strong T cell responses against viruses, microbial pathogens, and tumors. Therefore, the immunization using DC loaded with tumor-associated antigens is a powerful method for inducing anti-tumor immunity. The CTP (Cytoplasmic Transduction Peptide) technology developed by Creagene which can transport attached bio-polymers like nucleic acids or proteins into the cell with high permeation efficiency. As the active forms of PAP can mediate apoptotic processing, we used multimer forms of PAP as an inactive form for antigen pulsing of DCs. In this study, multimeric forms of CTP-rhPAP was obtained according to the advanced purification process and subsequently confirmed by gel filtration chromatography, western blot and Dynamic Light Scattering. Therefore, CTP-conjugated PA multimers transduced into the cytoplasm were efficiently presented on the cell surface without any harm effect on cells via MHC class I molecules and result in induction of a large number of effector cell.

Acute Pulmonary Toxicity and Body Distribution of Inhaled Metallic Silver Nanoparticles

  • Kwon, Jung-Taek;Minai-Tehrani, Arash;Hwang, Soon-Kyung;Kim, Ji-Eun;Shin, Ji-Young;Yu, Kyeong-Nam;Chang, Seung-Hee;Kim, Dae-Seong;Kwon, Yong-Taek;Choi, In-Ja;Cheong, Yun-Hee;Kim, Jun-Sung;Cho, Myung-Haing
    • Toxicological Research
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    • v.28 no.1
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    • pp.25-31
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    • 2012
  • The purpose of this study was to determine the acute pulmonary toxicity of metallic silver nanoparticles (MSNPs, 20.30 nm in diameter). Acute pulmonary toxicity and body distribution of inhaled MSNPs in mice were evaluated using a nose-only exposure chamber (NOEC) system. Bronchoalveolar lavage (BAL) fluid analysis, Western blotting, histopathological changes, and silver burdens in various organs were determined in mice. Mice were exposed to MSNPs for 6 hrs. The mean concentration, total surface area, volume and mass concentrations in the NOEC were maintained at $1.93{\times}10^7$ particles/$cm^3$, $1.09{\times}10^{10}\;nm^2/cm^3$, $2.72{\times}10^{11}\;nm^3/cm^3$, and 2854.62 ${\mu}g/m^3$, respectively. Inhalation of MSPNs caused mild pulmonary toxicity with distribution of silver in various organs but the silver burdens decreased rapidly at 24-hrs post-exposure in the lung. Furthermore, inhaled MSNPs induced activation of mitogen-activated protein kinase (MAPK) signaling in the lung. In summary, single inhaled MSNPs caused mild pulmonary toxicity, which was associated with activated MAPK signaling. Taken together, our results suggest that the inhalation toxicity of MSNPs should be carefully considered at the molecular level.

Preparation of Al/RDX/AP Energetic Composites by Drowning-out/Agglomeration and Their Thermal Decomposition Characteristics (결정화/응집에 의한 구형 Al/RDX/AP 에너지 복합체 제조 및 그 열분해 특성)

  • Lee, Jeong-Hwan;Shim, Hong-Min;Kim, Jae-Kyeong;Kim, Hyoun-Soo;Koo, Kee-Kahb
    • Applied Chemistry for Engineering
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    • v.28 no.2
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    • pp.214-220
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    • 2017
  • The spherical Al/RDX/AP composites with an average size of $550{\mu}m$ were successfully prepared by drowning-out/agglomeration (D/A) process. The surface morphology and dispersion of Al particles of those composites were investigated using SEM and EDS (energy dispersive spectrometry). As a result of thermal analysis, the onset temperature of thermal decomposition of the Al/RDX/AP composites by the D/A process was found to decrease about $50^{\circ}C$ and their thermal stability was shown to be relatively enhanced due to the increase of activation energy compared to those of using the physical mixing method. In the first decomposition region of AP, Prout-Tompkins model was shown to describe well the thermal decomposition of both composites by the physical mixing and D/A process. On the other hand, in the second decomposition region of AP, the decomposition mechanisms of composites by the physical mixing and D/A process were explained by the zero-order and contracting volume model, respectively.

Impacts of Elevated $CO_2$ on Algal Growth, $CH_4$ Oxidation and $N_2O$ Production in Northern Peatland (이탄습지에서 이산화탄소의 농도가 조류의 증식, 메탄 산화 및 아산화질소 생성에 미치는 영향)

  • Freeman, Chris;Kang, Ho-Jeong
    • Korean Journal of Ecology and Environment
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    • v.34 no.4 s.96
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    • pp.261-266
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    • 2001
  • Effects of elevated carbon dioxide ($CO_2$) on soil microbial processes were studied in a northern peatland. Intact peat cores with surface vegetation were collected from a northern Welsh fen, and incubated either under elevated carbon dioxide (700 ppm) or ambient carbon dioxide (350 ppm) conditions for 4 months. Higher algal biomass was found under the elevated $CO_2$ condition, suggesting $CO_2$ fertilization effect on primary production, At the end of the incubation, trace gas production and consumption were analyzed using chemical inhibitors. For methane ($CH_4$ ), methyl fluoride ($CH_3F$) was applied to determine methane oxidation rates, while acetylene ($C_2H_2$) blocking method were applied to determine nitrification and denitrification rates. First, we have adopted those methods to optimize the reaction conditions for the wetland samples. Secondly, the methods were applied to the samples incubated under two levels of $CO_2$. The results exhibited that elevated carbon dioxide increased both methane production (210 vs. $100\;ng\;CH_4 g^{-1}\;hr^{-1}$) and oxidation (128 vs. $15\;ng\;CH_4 g^{-1}\;hr^{-1}$), resulting in no net increase in methane flux. For nitrous oxide ($N_2O$) , elevated carbon dioxide enhanced nitrous oxide emission probably from activation of nitrification process rather than denitrification rates. All of these changes seemed to be substantially influenced by higher oxygen diffusion from enhanced algal productivity under elevated $CO_2$.

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Thermal property of geopolymer on fly ash-blast furnace slag system with the addition of alumina aggregate (알루미나 골재 첨가에 따른 플라이애쉬-고로슬래그계 지오폴리머의 열적특성)

  • Kim, Jin-Ho;Nam, In-Tak;Park, Hyun;Kim, Kyung-Nam
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.27 no.1
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    • pp.47-56
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    • 2017
  • In this study, the higher temperature thermal property of the fly ash-blast furnace slag system Geopolymer including alumina aggregate was investigated whether that Geopolymer will be or not useful as thermal-resistant construction materials. Under every mixing conditions, the crack on the surface of hardened body was not observed up to $800^{\circ}C$ and it corresponded with fact that level of changes was not significant before and after heating process. Residual compressive strength is most high when mixing Blast-Furnace Slag ratio is 60 wt% until temperature reaches $800^{\circ}C$. The major hydrates of hardened body of Geopolymer; amorphous halo pattern between $20{\sim}35^{\circ}$ (2theta) and mullite ($3Al_2O_3{\cdot}2SiO_2$) and quartz ($SiO_2$) was found during the experiment. Amorphous halo pattern was a aluminosilicate gel generated by geopolymeric polycondensation and it was found that the halo pattern of aluminosilicate gel was preserved up to $800^{\circ}C$. The patterns of aluminosilicate gel disappeared from $1,000^{\circ}C$ and crystal phases like gehlenite, calcium silicate, calcium aluminum oxide, microcline was observed with the increase of exposure temperature.

Full mouth Rehabilitation in a Patient with Occlusal Collapse with Vertical Dimension Increase (교합 붕괴 환자에서 수직 고경을 증가한 보철 수복 : 증례 보고)

  • Jo, Si-Hoon;Jeong, Su-Yang;Nam, Hyun-Seok;Song, Kwang-Yeob;Park, Ju-Mi;Ahn, Seung-Geun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.26 no.4
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    • pp.477-482
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    • 2010
  • In a case of multiple posterior teeth loss, antagonistic teeth extrude to the edentulous space and compensatory occlusion on the remained anterior teeth leads to occlusal trauma. Extrusion of antagonistic teeth breaks down occlusion plane and loss of posterior support bring about severe wear of remained teeth. In this situation, it is needed to restore remained teeth and edentulous space by increasing vertical dimension to obtain prosthodontic rehabilitation space and to correct occlusion plane. In this case report, the patient had a masticatory problem with loss of posterior teeth support and an esthetic problem of shortened anterior teeth. Before the tooth preparation for the prosthodontic restoration, the patient used removable device for 2 months to increase vertical dimension reversibly. After that, he got provisional fixed restoration with irreversible tooth reduction and used it for 3 months. It had spent 5 month to evaluate the adaptation state on final restoration with incresed vertical dimension. The increasing amount was 3 mm, which was relatively in less degree and masticatory system adapted to the increased vertical dimension without any pathologic changes. Final restoration was made to have equal-intensity contacts on all teeth in a verifiable centric relations and immediate disclusion of all posterior contacts the moment the mandible moves in any direction from centric relation. In addition, metal occlusion surface on posterior teeth was applied to prevent excessive muscle activation, occlusal trauma and the porcelain fracture.

Kinetics and Mechanism of the Oxidation of Sulfur Dioxide on Nickel Oxide-${\alpha}$-Ferric Oxide System (산화니켈-${\alpha}$ 형 산화철 상에서 이산화황의 산화 반응메카니즘)

  • Kyu Yong Lee;Yong Rok Kim;Sung Han Lee
    • Journal of the Korean Chemical Society
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    • v.27 no.3
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    • pp.183-188
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    • 1983
  • The catalytic oxidation of $SO_2$ has been investigated in the presence of vacuum-activated 10 mol % Ni-doped ${\alpha}-Fe_2O_3$ under various partial pressures of $SO_2\;and\;O_2$ at temperatures from 320 to $440{\circ}C$. Over the temperature range $320{\sim}440{\circ}C$, the activation energy is 13.8 $kcal{\cdot}mol^{-1}$. The oxidation rates have been correlated with 1.5 order kinetics; first order with respect to $SO_2$ and 0.5 order with respect to $O_2$. From the kinetic data and conductivity measurements, the adsorption, oxidation mechanism of $SO_2$ and the defect structure of vacuum-activated 10 mol % Ni-doped {\alpha}-Fe_2O_3$ are suggested. $O_2\;and\;SO_2$ appear to be adsorbed essentially as ionic species. Two surface sites, probably an $O^{2-}$ lattice and an oxygen vacancy which is induced by Ni-doping, might be required to adsorb $SO_2\;and\;O_2$. The conductivity measurements and kinetic data indicate that the adsorption process of $SO_2\;{(SO_2+O^{2-}}_{(latt)}{\rightleftharpoons}{{SO_3}^-}_{(ads)}+e')$ is the rate-determining step.

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