• 제목/요약/키워드: CO1-5P

검색결과 4,240건 처리시간 0.028초

$La_{0.5}Ce_{0.5}Co_{1-x}Cu_xO_{3-{\alpha}}$ Perovskite촉매의 선택적 CO 산화반응 및 특성 분석에 관한 연구 (Study on Catalytic Activity of the Selective CO Oxidation and Characterization Using $La_{0.5}Ce_{0.5}Co_{1-x}Cu_xO_{3-{\alpha}}$ Perovskite Catalysts)

  • 손정민
    • 한국수소및신에너지학회논문집
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    • 제18권2호
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    • pp.116-123
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    • 2007
  • [ $La_{0.5}Ce_{0.5}Co_{1-x}Cu_xO_{3-{\alpha}}$ ](X=0, 0.1, 0.3, 0.5) perovskites were prepared by coprecipitation method at pH 7 or pH 11 and its catalytic activity of selective CO oxidation was investigated. The characteristics of these catalysts were analyzed by $N_2$ adsorption, X-ray diffraction(XRD), SEM, $O_2$-temperature programmed desorption(TPD). The pH value at a preparation step made effect on particle morphology. The smaller particle was obtained with a condition of pH 7. The better catalytic activity was observed using catalysts prepared at pH 7 than pH 11. The maximum CO conversion of 98% was observed over $La_{0.5}Ce_{0.5}Co_{0.7}Cu_{0.3}O_{3-{\alpha}}$ at $320^{\circ}C$. Below $200^{\circ}C$, the most active catalyst was $La_{0.5}Ce_{0.5}Co_{0.9}Cu_{0.1}O_{3-{\alpha}}$, of which conversion was 92% at $200^{\circ}C$. By the substitution of Cu, the evolution of ${\alpha}$-oxygen was remarkably enhanced regardless of pH value at preparation step according to $O_2$-TPD. Among the different ${\alpha}$-oxygen species, the oxygen species evolved between $400^{\circ}C$ and $500^{\circ}C$, gave the better catalytic performance for selective CO oxidation including $La_{0.5}Ce_{0.5}CoO_3$ in which Cu was absent.

7-Nitroso-8-Hydroxyquinoline-5-Sulfonate 에 依한 Co (Ⅱ) 의 吸光光度定量 (Spectrophotometric Determination of Co (Ⅱ) with 7-Nitroso-8-Hydroxyquinoline-5-Sulfon)

  • 이동형
    • 대한화학회지
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    • 제9권2호
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    • pp.101-105
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    • 1965
  • 7-Nitroso-8-hydroxyquinoline-5-sulfonate(NHQS)는 pH 4.5에서 Co(Ⅱ)와 安定한 赤色 complex를 形成하므로 이것을 利用하여 NHQS에 依한 Co(Ⅱ)의 吸光光度定量方法을 檢討하였다. 吸光度는 528$m{\mu}$, $25^{\circ}C$에서 測定하였다. Co(Ⅱ)의 濃度 0.3∼6p.p.m에서 Beer의 法則은 成立하며 complex의 分子吸光係數는 $1.1{\times}10^4$이었다. 共存이온中 Fe(Ⅱ), Fe(Ⅲ), Cu(Ⅱ), Mn(Ⅱ), Hg(Ⅰ), CN-, EDTA 等은 本定量에서 妨害가 된다. Complex의 組成을 몰比法과 連續變化法으로 檢討한 結果 NHQS와 Co(Ⅱ)의 몰比는 3:1이었다.

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Synthesis, Characterization, and Catalytic Properties of Gp 6 Metal Complexes of 1-N,N-dimethylaminomethyl-$1^{\prime}$,2-bis(diphenylphosphino)ferrocene (FcNPP). X-ray Crystal Structure of W$(CO)_4({\eta}^2-FcNPP(O)-P,N)$

  • Kim, Tae-Jeong;Kim, Yong-Hoon;Kim, Eun-Jin;Oh, Sang-Ho;Kim, Hong-Seok;Jeong, Jong-Hwa
    • Bulletin of the Korean Chemical Society
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    • 제15권5호
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    • pp.379-386
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    • 1994
  • Reactions of 1',2-bis(diphenylphosphino)-l-(N,N-dimethylaminomethyl)ferrocene (FcNPP) with $M(CO)_6$ (M=Cr, Mo, W) in the presence of TMNO (Trimethylamine oxide) in a stoichiometric ratio of 1 : 1.5 : 3.5 produced a series of Gp 6 metal carbonyl derivatives with a variety of coordination modes: M(CO)$_4({\eta}^2$-FcNPP-P,P) (M=Cr, Mo, W), $M(CO)_5({\eta}^1-FcNPP-P) (M=Mo, W)\;,\; M_2(CO)_9({\eta}^1\;,\;{\eta}^2-FcNPP-P,P,N) (M=Cr, Mo)\;,\;M_2(CO)_{10}({\eta}^1\;,\;{\eta}^1-FcNPP-P,P) (M=Cr, Mo, W)\;, and\;W(CO)_4({\eta}^2-FcNPP(O)-P,N)$. All these complexes were characterized by microanalytical and spectroscopic techniques. In one case, the structure of W(CO)$_4({\eta}^2$-FcNPP(O)-P,N) was determined by X-ray crystallography. Crystals are monocinic, space group P$2_{1/C}$, with a=10.147(2), b=19.902(3), c=19.821(4) ${\AA},\;{\beta}=96.88(2)^{\circ},\;V=3974(l){\AA}^3$, Z=4, and $D_{calc}=1.64 g cm^{-3}$. The geometry around the central tungsten metal is a distorted octahedron, with the nitrogen and phosphorus atoms being cis to each other. Some of these complexes exhibited catalytic activities in the allylic oxidation and epoxidation of cholesterly acetate. Other oxidation products were also formed with the different chemical yields and product distribution depending upon the ligand and the central metal.

가압하에서 인도네시아 아역청탄촤의 $CO_2$ 가스화 반응성에 관한 실헙적 연구 (Gasification Kinetics of an Indonesian Subbituminous Coal Char Reactivity with $CO_2$at Elevated Pressure)

  • 안달홍;고경호;이종민;주용진;김종진
    • 에너지공학
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    • 제10권3호
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    • pp.206-213
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    • 2001
  • 가압분류층반응기(PDTF)를 이용하여 가압하에서 인도네시아 아역청탄촤의 $CO_2$, 가스화 반응성을 연구하였다. 가스화온도(900~140$0^{\circ}C$), 이산화탄소분압 (0.1-0.5MPa) 및 시스템전압(0.5, 0.7, 1.0 및 1.5MPa)이 촤-$CO_2$반응율에 미치는 영향을 결정하였다. 동일한 $CO_2$, 분압과 온도조건하에서도 가스화반응속도(gasification rate)는 시스템전압에 따라 영향을 받는 것이 발견되었다. 시스템압력이 변화하는 조건하에서의 가스화반응속도을 모사하기 위하여 n차반응속토식 R=k$P^{n}$ $_{gas}$에 시스템전압항을 추가하여 R=k$P^{n}$ $_{gas}$ $P^{m}$ $_{total}$ 으로 수정하였다. 고온가압하에서의 인도네시아 아역청탄촤-$CO_2$ 가스화반응율은 dX/dt=(174.1)exp(-71.5/RT) ( $P_{CO2}$)$^{0.40}$( $P_{total}$ )$^{0.65}$(1-X)$^{2}$ 3/로 표현할 수 있을 것이다.것이다.것이다.다.

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Expression Analyses of MicroRNAs in Hamster Lung Tissues Infected by SARS-CoV-2

  • Kim, Woo Ryung;Park, Eun Gyung;Kang, Kyung-Won;Lee, Sang-Myeong;Kim, Bumseok;Kim, Heui-Soo
    • Molecules and Cells
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    • 제43권11호
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    • pp.953-963
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    • 2020
  • Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an infectious disease with multiple severe symptoms, such as fever over 37.5℃, cough, dyspnea, and pneumonia. In our research, microRNAs (miRNAs) binding to the genome sequences of severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory-related coronavirus (MERS-CoV), and SARS-CoV-2 were identified by bioinformatic tools. Five miRNAs (hsa-miR-15a-5p, hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-16-5p, and hsa-miR-196a-1-3p) were found to commonly bind to SARS-CoV, MERS-CoV, and SARS-CoV-2. We also identified miRNAs that bind to receptor proteins, such as ACE2, ADAM17, and TMPRSS2, which are important for understanding the infection mechanism of SARS-CoV-2. The expression patterns of those miRNAs were examined in hamster lung samples infected by SARS-CoV-2. Five miRNAs (hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-221-3p, hsa-miR-140-3p, and hsa-miR-422a) showed differential expression patterns in lung tissues before and after infection. Especially, hsa-miR-15b-5p and hsa-miR-195-5p showed a large difference in expression, indicating that they may potentially be diagnostic biomarkers for SARS-CoV-2 infection.

혐기성소화의 물질분해 특성에 미치는 CO2 분압의 영향 (Effects of CO2 partial pressure on the characteristics of organic matter degradation in anaerobic digestion)

  • 김영철;엄태규;이무강;차기철;노이케 타쯔야
    • 상하수도학회지
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    • 제10권4호
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    • pp.111-118
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    • 1996
  • Effects of $CO_2$ partial pressure($pCO_2$) on the characteristics of methane production rate and organic matter degradation in anaerobic digestion were investigated by using anaerobic chemostat type reactors at $35{\pm}1^{\circ}C$, at the HRT of 7days. The $pCO_2$ of the reactors was controlled in the range from 0.1 to 0.8 atm. Since the $pCO_2$ in an uncontrolled condition was about 0.4atm, $N_2$ was added for the reactors controlled of $pCO_2$ of between 0.1 and 0.4atm. At $pCO_2$ of 0.5 atm, the methane production rate was approximately 20% more that in an uncontrolled condition of $pCO_2$. Based on the carbon mass balance, it was concluded that methane production was related to the increment of removal organic carbon and consumption of $CO_2$. At $pCO_2$ of 0.5atm, the methane production by the increment of removal substrates increased 13.6%, on the orther hand, hand, the methane production by the conversion of $CO_2$ to methane increased 6.4%.

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새로운 Fatty Acid Amide Hydrolase 저해제로서 5,5'-Diphenylimidazolidine-2,4-dione 유도체의 리간드 설계 (Ligand Design of 5,5'-Diphenylimidazolidine-2,4-dione Analogues as A New Class of Potent Inhibitors of Fatty Acid Amide Hydrolase)

  • 조종운;성민규;성낙도
    • Applied Biological Chemistry
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    • 제51권2호
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    • pp.119-123
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    • 2008
  • 3-치환된 5,5'-diphenylimidazolidine-2,4-dione 유도체(1-22)들의 fatty acid amide hydrolase (FAAH) 저해활성에 관한 3차원적인 정량적 구조와 활성과의 관계(3D-QSARs)를 비교 분자장 분석(CoMFA)과 비교분자 유사성 지수분석(CoMFA) 방법으로 각각 검토하였다. CoMFA A1 모델과 CoMSIA 2F 모델 모두 상관성과 예측성이 양호하였다. 두 모델의 정보에 의한 등고도에 따라 설계된 X=I, Y=$N_2{^+}$-치환체(P1: $Pred.pI_{50}$=6.55)는 FAAH에 대하여 가장 높은 저해활성을 나타내었다.

인이 도핑된 NiCo2O4 전극 제조 공정의 간소화를 통한 전극 특성의 변화 (Variations in electrode characteristics through simplification of phosphorus-doped NiCo2O4 electrode manufacturing process)

  • 이석희;차현진;박정환;손영국;황동현
    • 한국표면공학회지
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    • 제56권5호
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    • pp.299-308
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    • 2023
  • In this study, phosphorus (P)-doped nickel cobaltite (P-NiCo2O4) and nickel-cobalt layered double hydroxide (P-NiCo-LDH) were synthesized on nickel (Ni) foam as a conductive support using hydrothermal synthesis. The thermal properties, crystal structure, microscopic surface morphology, chemical distribution, electronic state of the constituent elements on the sample surface, and electrical properties of the synthesized P-NiCo2O4 and P-NiCo-LDH samples were analyzed using thermogravimetric analysis-differential scanning calorimetry (TGA-DSC), X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The P-NiCo2O4 electrode exhibited a specific capacitance of 1,129 Fg-1 at a current density of 1 Ag-1, while the P-NiCo-LDH electrode displayed a specific capacitance of 1,012 Fg-1 at a current density of 1 Ag-1. When assessing capacity changes for 3,000 cycles, the P-NiCo2O4 electrode exhibited a capacity retention rate of 54%, whereas the P-NiCo-LDH electrode showed a capacity retention rate of 57%.

Evidence for Nitrogen-Bonded Acrylonitrile to Iridium (Ⅰ) in Acrylonitrilecarbonylbis(triphenylphosphine)iridium (Ⅰ) perchlorate

  • Park, Soon-Heum;Park, Hwa-Kun;Chin, Chong-Shik
    • Bulletin of the Korean Chemical Society
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    • 제5권4호
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    • pp.167-169
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    • 1984
  • Analyses of $_1$H-NMR, infrared and electronic spectral data for $[Ir(CH_2 = CHCN)(CO)(P(C_6H_5)_3)_2]ClO_4 (1)$prepared by the reaction of $Ir(OClO_3)(CO)(P(C_6H_5)_3)_2$ with $CH_2 = CHCN$, agree with the suggestion that 1 is a mixture of the nitrogen-bonded acrylonitrile complex, $[(CO)(P(C_6H_5)_3)_2Ir-NCCH = CH_2]ClO_4$ and other compound which may be the C = C ${\Pi}$ -system-bonded acrylonitrile complex, "[(CO)(P(C6H5)3)2Ir-CHCN = CH2]ClO4.

새로운 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclo-hex-2-en-1-one 유도체들의 제초활성에 관한 비교분자 유사성지수 분석 (Comparative Molecular Similarity Indices Analyses (CoMSIA) on the Herbiridal Activities of New 5-benzofuryl-2-[1-(alkoxy-imino)alkyl]-3-hydroxycyclo-hex-2-en-1-one Derivatives)

  • 성낙도;정기성;정훈성;정영호
    • 농약과학회지
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    • 제10권1호
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    • pp.7-14
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    • 2006
  • 새로운 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclohex-2-en-1-one 유도체들의 3차원적인 정량적 구조와 발아 전, 벼(Oryza sativa L.)와 논피(Echinochloa crus-galli)에 대한 제초활성과의 관계를 비교분자 유사성 지수분석(CoMSIA) 방법으로 연구하였다. 가장 양호한 CoMSIA 모델로서 벼에 대한 A5 모델($r^2_{cv.}=0.569$$r^2_{ncv.}=0.941$)은 주로 소수성장(39.7%)과 입체장(31.6%) 그리고 논피에 대한 B4 모델($r^2_{cv.}=0.595$$r^2_{ncv.}=0.933$)은 정전기장(46.7%)과 수소결합 받게장(30.8%)에 각각 의존적이었다. B4 모델에 의하여 예측된 $R_1=SF_5,\;R_2=R_3=R_4=H(P1)$ 치환체(벼: $pI_{50}=4.84$ 및 논피: $pI_{50}=7.21$, ${\Delta}pI_{50}=2.37$)는 논피에 대하여 가장 높은 제초활성을 나타내었으며 두 초종 간 선택성이 가장 큰 치환체이었다.