• 제목/요약/키워드: Co-agent

검색결과 1,615건 처리시간 0.031초

무전해 Co-Cu-P 도금속도에 미치는 도금 조건과 표면상태의 영향 (Effect of Plating Condition and Surface on Electroless Co-Cu-P Alloy Plating Rate)

  • 오이식
    • 동력기계공학회지
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    • 제4권2호
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    • pp.31-39
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    • 2000
  • Relationships between the plating condition and the plating rate of the deposition film for the electroless plating of Co-Cu-P alloy were discussed in this report. The result obtained from this experiment were summarized as follow ; The optimum bath composition was consisted of 0.8 ppm thiourea as a stabilizing agent. Composition of the deposit was found to be uniform after two hours of electroless plating. Plating rates of nickel-catalytic surface and zincate-catalytic surface were found to be very closely equal, but the plating time of nickel-catalytic surface took longer than that of the zincated-catalytic surface.

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캐피라리 전기 영동법에 의한 비시안 무전해 Au 도금액의 분석 (Analysis of cyanide free electroless Au plating solution by capillary elecrophoresis)

  • 한재호;김동현
    • 한국표면공학회지
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    • 제55권2호
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    • pp.120-132
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    • 2022
  • In the non-cyanide-based electroless Au plating solution using thiomalic acid as a complexing agent and aminoethanethiol as a reducing agent, analysis of each component constituting the plating solution is essential for the analysis of the reaction mechanism. And component analysis in the plating solution is important for monitoring component changes in the plating process and optimizing the management method. Capillary Electrophoresis (CE) method is rapid, sensitive and quantitative and could be readily applied to analysis of Aun+ ion, complexing agent and reducing agent in electroless Au plating solution. In this study, the capillary electrophoresis method was used to analyze each component in the electroless Au plating solution in order to elucidate the complex bonding form and the plating mechanism of the non-cyanide-based electroless Au plating bath. The purpose of this study was to establish data for optimizing the monitoring and management method of plating solution components to improve the uniformity of precipitation and stability. As a result, it was confirmed that the analysis of thiomalic acid as a complexing agent and Aun+ ions and the analysis of aminoethanethiol as a reducing agent were possible by capillary electrophoresis. In the newly developed non-cyanide-based electroless Au plating solution, it was confirmed that Aun+ ions exist in the form of Au+ having a charge of +1, and that thiomalic acid and Au+ are combined in a molar ratio of 2 : 1. In addition, it was confirmed that aminoethanethiol can form a complex by combining with Au+ ions depending on conditions as well as acting as a reducing agent.

가스계 소화시스템관련 안전기술 (A Technical Description on The Safety Aspects related To Gas Suppression Fire Protection System)

  • 이창욱
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 2002년도 춘계학술대회 논문집
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    • pp.21-29
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    • 2002
  • 가스계 소화약제시스템의 인명안전 또는 기타 안전관련으로 CO2 시스템과 청정약제시스템을 중심으로 기술해보았습니다. 인명에 대한 위험을 최소화하면서 CO2 소화시스템의 혜택을 얻기 위해서는 설계, 시공, 유지관리면에서의 인명안전에 대해 상당한 관심을 기울여야한다. 청정 소화약제를 통상의 거주구역에 사용할 경우의 주요요소는 독성문제이다. 할로겐화탄소약제 테스트에서의 주요 관점은 급성효과, 즉 단기간 노출의 경우이다. 주요급성효과에는 마취성과 심장감작성이 있다. 불활성가스약제의 경우 주요 신체적 영향으로는 산소농도의 저하문제를 들 수 있다.

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리튬이온전지용 Conducting Agents의 전기화학적 성능에 미치는 영향 (Effects on Electrochemical Performances of Conducting Agents for Lithium-ion Batteries)

  • 이창우;이미숙;문성인;김영규;김병화;김동훈
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.593-594
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    • 2005
  • Lithium-ion batteries have used the layered $LiCoO_2$ materials as cathodes, but Co is relatively toxic and expensive. In this regard, the spinel $LiMn_2O_4$ has become appealing because manganese is inexpensive and environmentally benign. In general, cathodes for lithium ion batteries include carbon as a conductive agent that provides electron transfer between the active material and the current collector. In this work, we selected Acetylene Black and Super P Black as conducting agents, and then carried out comparative investigation for the performances of the cells using different conducting agents with different particle size. As a consequence, Li/$LiMn_2O_4$ cells with Super P Black show better electrochemical performances than those with Acetylene Black.

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보강형 고화제를 이용한 친환경 도로노반조성 방안 (Construction of Environmentally Friendly Roadbed by Reinforecing Type Soil Solidification Agent)

  • 고용국
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2004년도 춘계학술발표회
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    • pp.667-671
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    • 2004
  • The purpose of this paper is to study on the construction of environmentally friendly roadbed by reinforcing type soil solidification agent. The soil amendment agent used in this study is friendly to the environment, and has a function of soil-cement-agent solidification. The soil amendment agent was admixed with reinforced fiber material for enhancement of strength and durability of roadbed. The project of trial field test of roadbed construction with special reinforcing soil treatment agent was performed in Gyunggido on December 2003. A series of field and laboratory experiments including unconfined compressive strength, permeability were carried out to investigate the physical and mechanical characteristics of solidified roadbed treated by this reinforced solidifying agent. The results of this research showed that the roadbed using normal and poor soil could be efficiently constructed by treatment of this reinforcing type solidification agent admixed with fiber material.

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안정화제 주입량에 따른 중금속 오염토양의 안정화 분석 (The Dose Effect of Stabilizing Agent on Stabilization of Heavy Metals in Soil)

  • 최희철;윤이준;이병용;최상일
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제25권4호
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    • pp.7-13
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    • 2020
  • In this study, a stabilization method was applied to stabilize heavy metals in soils collected from a domestic contaminated area and a Canadian mine site. The stabilizing agent used in the experiment was a solidifying agent developed by KERT Co., Ltd., Korea. The agent was applied to the samples at varying weight ratios of 0, 2, 5, 7, and 10% (w/w). and the concentrations of heavy metals in the effluent were monitored at predetemined time intervals. The results indicated that the stabilization efficiency of heavy metals (Cd, Cu, Pb) increased proportionally until the agent was increased to 5%, which showed almost no leaching of heavy metals after 28 days after agent application. Therefore, addition of 5% relative to soil mass was proposed to be the optimum dose for the stabilization agent.

Poly(ethylene glyco1) diacrylate로 가교된 Poly(N-isopropylacrylamide) Hydrogel의 부피 상전이 특성 (Velume Phase Transition of Poly (N-isopropylacrylamide-co-sodium methacrylate) Hydrogel Crosslinked with Poly(ethylene glycol) diacrylate)

  • 김선아;한영아;손성옥;지병철
    • 폴리머
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    • 제26권5호
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    • pp.653-660
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    • 2002
  • 가교제 poly(ethylene glycol) diacrylate (PEGDA)를 사용하여 제조한 poly(N-iso-propylacrylamide) (PNIPAAm) 및 poly (N-isopropylacrylamide-co-sodium methacrylate) (P(NIPAAm-co-SMA)) hydrogels의 부피 상전이 현상을 함수율과 표면적의 변화로 고찰하였다. Hydyogel의 부피 상전이 온도는 가교제의 농도에는 영향을 받지 않았으나 공단량체인 SMA의 소량 첨가로 4$0^{\circ}C$ 이상 상승하였다. 특히 PEGDA를 가교제로 사용하였을 경우 가교 길이가 길어짐에 따라 부피 상전이 온도가 더 높게 상승하였다. PNIPAAm 및 P(NIPAAm-co-SMA) hydrogels의 표면적 역시 부피 상전이 온도를 전후하여 감소하였는데 이는 부피 상전이 과정에서 기공의 크기가 현저하게 감소하였기 때문이다. 따라서 표면적과 기공 크기의 변화가 부피 상전이를 나타내는 주요한 인자임을 알 수 있다.

반응형 음이온화제 처리 면직물에 대한 중금속 이온의 흡착특성 (The Adsorption Properties of Heavy Metal Ions on to Cotton Fabrics Treated with Reactive Anionic Agent)

  • 김미경;윤석한;김태경;임용진
    • 한국염색가공학회지
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    • 제17권1호
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    • pp.20-29
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    • 2005
  • Cotton fabric was treated with a reactive anionic agent in order to have anionic sites(-S03-) on it, which made it possible for the fabric to adsorb various cationic materials. In this study, the adsorptivity of various heavy metal ions such as Pb(II), Cd(II), Cr(III), Co(II), Cu(II), Ni (II) and Cr(VI) on the cotton fabrics treated with anionic agent was examined at the various conditions; concentrations of heavy metal ions, pHs of solution, reaction time and temperature. As a result, the adsorptivity of the heavy metal ions on the cotton fabrics treated with the anionic agent was highly increased comparing to that of untreated cotton fabrics. The order of the adsorptivity was as follows: $Pb(II)>Cd(II)>Cu(II)\geqNi(II)\geqCo(II)>Cr(III)\ggCr(VI)$. The adsorption amounts of most heavy metal ions were increased in weak alkaline conditions and were reached to an adsorption equilibrium within 10 ~ 30 minutes. The maximum adsorption ratios of Pb(II) and Cd(II) were respectively 99% and 80% of the initial concentration of heavy metal ions. Therefore the anionized cotton fabrics seem to be utilized as an adsorption fabrics for the removal of heavy metal ions in the waste water.

액상환원공정을 이용한 나노 코발트 분말의 합성 (Preparation of the Nano Cobalt Powder by Wet Chemical Reduction Method)

  • 홍현선;고영대;강이승;김건홍;정항철
    • 한국분말재료학회지
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    • 제18권3호
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    • pp.244-249
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    • 2011
  • Spherical nanosized cobalt powder with an average size of 150-400 nm was successfully prepared at room temperature from cobalt sulfate heptahydrate ($CoSO_4{\cdot}7H_2O$). Wet chemical reduction method was adopted to synthesize nano cobalt powder and hypophosphorous acid ($H_3PO_2$) was used as reduction agent. Both the HCP and the FCC Co phase were developed while $CoSO_4{\cdot}7H_2O$ concentration ranged from 0.7 M to 1.1 M. Secondary phase such as $Co(OH)_2$ and $CO_3O_4$ were also observed. Peaks for the crystalline Co phase having HCP and FCC structure crystallized as increasing the concentration of $H_3PO_2$, indicating that the amount of reduction agent was enough to reduce $Co(OH)_2$. Consequently, a homogeneous Co phase could be developed without second phase when the $H_3PO_2/CoSO_4{\cdot}7H_2O$ ratio exceeded 7.