• 제목/요약/키워드: Carbon formation

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Effect of Medium Conditions on Adventious Bud Formation of Mulberry Winter Bud Leaflet (배지조건이 뽕나무 동아엽편의 불정아형성에 미치는 영향)

  • 성규병;정정박명;김호락;구태원
    • Journal of Sericultural and Entomological Science
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    • v.37 no.1
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    • pp.6-9
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    • 1995
  • To establish a regeneration system of mulberry through the adventitious bud formation of winter bud leaflet, medium conditions were examined. Adventitious bud formation rate of mulberry winter bud leaflet on the medium containing different concentrations of BA and TDZ as the growth regulators was high on 5mM BA and 0.5mM TDZ. The effect of preculture on the medium containing BA or TDZ was affected not only by the concentration of growth regulators but the duration of preculture. Fructose as carbon source was effective on adventitious bud formation.

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Fiber Surfaces and Interlaminar Shear Strengths of Electrolytic Ni-plated Carbon Fiber/Epoxy Resin Composites (전해 니켈도금 처리에 따른 탄소섬유/에폭시 수지 복합재료의 섬유표면 및 기계적 계면전단 강도)

  • 박수진;장유신;이재락;김진석
    • Polymer(Korea)
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    • v.24 no.5
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    • pp.721-727
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    • 2000
  • The electrolytic plating of a metallic nickel on carbon fiber surfaces was carried out to improve mechanical interfacial properties of carbon fiber/epoxy resin composites. The surface characteristics of carbon fibers and the mechanical interfacial properties of final composites were characterized by X-ray photoelectron spectroscopy (XPS) and interlaminar shear strength (ILSS), respectively. It was found that the electrolytic Ni-plating conditions significantly affected the degree of adhesion at interfaces between carbon fibers and epoxy resin matrix in a composite system. Especially, the increase of O,$_{1s}$/$C_{1s}$ ratio, production of NiO groups, and formation of metallic nickel on the nickel-plated carbon fiber surfaces led to an increase of the ILSS of the composites. Also, the ILSS of the composites was greatly correlated with the $O_{1s}$/$C_{1s}$ ratio of the carbon fibers treated in this work.is work.

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Derivation of Optimal Design Variables Considering Carbon Monoxide Emission Characteristics of Commercial Gas Stove Burners (업소용 가스레인지 버너의 일산화탄소 배출 특성을 고려한 최적 설계변수 도출)

  • Il Kon Kim;Taehoon Kim
    • Journal of the Korean Society of Safety
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    • v.39 no.1
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    • pp.1-8
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    • 2024
  • Commercial gas stoves feed primary air to the burner and burn the fuel-air mixture in a partially premixed combustion. This mechanism produces carbon monoxide during combustion. In this study, design parameters of a commercial gas stove were optimized by considering the carbon monoxide emission. Gas consumption rate, carbon monoxide emission, and water boiling temperature as a heating performance were determined. Carbon monoxide emission was measured using a Korean Industrial Standards standard collector. Water boiling temperature was measured by first soaking the pot in water for approximately 10 min and then heating the pot filled with water. A thermocouple was installed inside the pot. Carbon monoxide increased as the nozzle diameter was increased and the burner-pot height was decreased. This result was due to the insufficient mixing between the fuel and air. Heating performance was enhanced when the nozzle diameter was increased and the burner-pot height was decreased. However, the heating performance deteriorated when the nozzle diameter was 1.8 mm and the burner-pot height was reduced to 50 mm. This phenomenon was due to the formation of a flame on the side of the pot. A merit factor was defined to find the optimal design parameters to satisfy gas consumption rate, carbon monoxide emission, and heating performance. Optimal design values were established to be a nozzle diameter of 1.5 mm and a burner-pot height of 60 mm.

Cultural Characteristics and Log-Mediated Cultivation of the Medicinal Mushroom, Phellinus linteus

  • Hur, Hyun
    • Mycobiology
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    • v.36 no.2
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    • pp.81-87
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    • 2008
  • The optimal conditions for mycelial growth of Phellinus linteus ATCC 26710 were determined to be a log length of 20 cm, temperature of $30^{\circ}C$ and pH of 6.0. Mycelial growth was excellent on the mushroom complete medium, and was optimal when sucrose, man nose and glucose were supplied as carbon sources. Potassium nitrate and sodium nitrate as nitrogen sources supported good mycelial growth. To evaluate P. linteus mycelial colonization on logs, sterilized short log inoculation, drilling inoculation and log-end sandwich inoculation techniques were used. Only sterilized short log inoculation produced good mycelial colonization. Initial mycelial growth and full mycelial colonization were best on 20 cm logs having 42% moisture content. The initial mycelial growth of P. linteus was accelerated over 12hr of sterilization. Basidiocarp formation was optimal using a burying method of logs after $5{\sim}6$ months, and fruiting body formation was superior in cultivation house conditions of $31{\sim}35^{\circ}C$ and in excess of 96% relative humidity.

A Survey of THMs Formation in J Water Purification Plant and Its Reduction by PAC Treatment during Summer (J 정수장의 하절기 THMs 생성현황과 분말활성탄 처리에 의한 저감효과)

  • Hwang, Gap-Soo;Lee, Jang-Hoon
    • Journal of Environmental Health Sciences
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    • v.25 no.3
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    • pp.1-6
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    • 1999
  • This study was conducted to survey trihalomethane(THMs) levels in finished water of J water treatment plant and examine its reduction by powder activated carbon(PAC) treatment. Samples were collected weekly based and head-space technique was employed to determine THMs levels by G.C-ECD. THMs levels in finished waters were highest in August and showed close relationship with water temperature. All the samples satisfied the drinking water limit(100 ${\mu}$g/l) for THMs. The individual formation rates of THMs were 64.8% for CHCl$_3$, 28.4% for CHCl$_2$BR, 6.5% for CHClBr$_2$ and 0.3% for CHBr$_3$, respectively and showed little monthly difference. The reduction efficiency of THMs formation by PAC treatment was 67% during July and August. Bromine substituents were more efficiently reduced than CHCl$_3$ by PAC.

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Effect of Carboxylic Acid on the Hydration of Plaster of Paris under Alkalinity (알카리성 분위기에서 소석고의 수화에 미치는 카르복실산의 영향)

  • 이승헌
    • Journal of the Korean Ceramic Society
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    • v.31 no.10
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    • pp.1107-1114
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    • 1994
  • Although various theories have been presented on the mechanism of setting retardation of plaster in addition to organic admixtures. The purpose of this paper is that Hydration studies of plaster of paris in the presence of carboxylic acids under alkalinity are examined in the coordination chemistry. Setting of plaster of paris is retarded by the addition of carboxylic acids except oxalic acid. And setting of plaster of paris contained 5 wt% of Ca(OH)2 is also retarded by the addition of above-mentioned carboxylic acids. The degree of retarding effect under alkalinity is found to be a function of the number of the functional group and the length of carbon chain of carboxyl acids. These reasons are attributed to the soluble complex formation, that is calcium complex formation between calcium ion and carboxylic acids. The author's proposal was confirmed by the results of electrical conductivity measurement. The formation of calcium complex was surpported by IR spectra.

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Porous Silica Particles As Chromatographic Separation Media: A Review

  • Cheong, Won Jo
    • Bulletin of the Korean Chemical Society
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    • v.35 no.12
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    • pp.3465-3474
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    • 2014
  • Porous silica particles are the most prevailing raw material for stationary phases of liquid chromatography. During a long period of time, various methodologies for production of porous silica particles have been proposed, such as crashing and sieving of xerogel, traditional dry or wet process preparation of conventional spherical particles, preparation of hierarchical mesoporous particles by template-mediated pore formation, repeated formation of a thin layer of porous silica upon nonporous silica core (core-shell particles), and formation of specific silica monolith followed by grinding and calcination. Recent developments and applications of useful porous silica particles will be covered in this review. Discussion on sub-$3{\mu}m$ silica particles including nonporous silica particles, carbon or metal oxide clad silica particles, and molecularly imprinted silica particles, will also be included. Next, the individual preparation methods and their feasibilities will be collectively and critically compared and evaluated, being followed by conclusive remarks and future perspectives.