• Transactions of the Korean hydrogen and new energy society
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• v.18 no.2
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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.

• Journal of the Korean Chemical Society
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• v.9 no.2
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• pp.101-105
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• 1965

Spectrophotometric method for the determination of Co(Ⅱ) is developed based on the fact that Co(Ⅱ) forms a stable red complex with 7-nitroso-8-hydroxyquinoline-5-sulfonate at pH 4. 5. The absorbance is measured at 528$m{\mu}$, $25^{\circ}C$. Beer's law is followed in the concentration range of 0. 3 to 6. 0 p.p.m. of Co(Ⅱ) and molar extinction coefficient of the complex was $1.1{\times}10^4$. Of the diverse ions checked, Fe(Ⅱ), Fe(Ⅲ), Cu(Ⅱ), Mn(Ⅱ), Hg(Ⅰ), CN-, EDTA interfere. The composition of the complex is found to be 3:1 ligand to metal species by mole ratio and continuous variation methods.

• Bulletin of the Korean Chemical Society
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• v.15 no.5
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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.

• Journal of Energy Engineering
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• v.10 no.3
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• pp.206-213
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• 2001

Gasification kinetics of an Indonesian sub-bituminous coal-char with $CO_2$at elevated pressure was investigated with a pressurised drop tube furnace reactor. The effects of reaction temperature (900~140$0^{\circ}C$), partial pressure of carbon dioxide (0.1~0.5 MPa), and total system pressure (0.5, 0.7, 1.0, 1.5MPa) on gasification rate of the coal char with $CO_2$have been determined. It was found that the gasification rate was dependent on the total system pressure with the same partial pressure and temperature. The $n^{th}$ order rate equation (R=k $P^{g}$ $_{asn}$) was modified to be R=k $P^{g}$ $_{asn}$ $P^{m}$ $_{total}$ to describe the gasification rate where the total system pressure was changed. The gasification reaction rate of char-$CO_2$at high temperature and elevated pressure may be expressed as dX/dt=(174.1)exp(-71.5/RT)( $P_{CO2}$)0.40( $P_{total}$ )0.65(1-X)$^{2}$ 3/.X> 3/.

• Molecules and Cells
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• v.43 no.11
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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.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.4
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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%.

• Applied Biological Chemistry
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• v.51 no.2
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• pp.119-123
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• 2008

3D-QSARs (3 dimensional quantitative structrue-activity relationships) on the inhibition activities of 3-substituted-5,5'-diphenylimidazolidine-2,4-dione derivatives (1-22) against FAAH (fatty acid amide hydrolase) were studied quantitatively using CoMFA (comparative molecular field analysis) and CoMSIA (comparative molecular similarity indice analysis) methods. The statistical results of the CoMFA 1A and CoMSIA 2F model are better predictability and fitness. And also, the designed X=I, Y=$N_{2}^{+}$-substituent (P1: $Pred.pI_{50}$=6.55), according to the contour maps with information of the two models, showed the most inhibition activity against FAAH.

• Journal of the Korean institute of surface engineering
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• v.56 no.5
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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%.

• Bulletin of the Korean Chemical Society
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• v.5 no.4
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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.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.7-14
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• 2006

Three-dimensional quantitative structure-activity relationships (3D-QSARs) on the herbicidal activities against in-vitro pre-emergence rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) by new 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclohex-2-en-1-one derivatives were studied quantitatively using comparative molecular similarity indices analysis (CoMSIA) methodology. The optimized CoMSIA model(A5: $r^2_{cv.}=0.569$ & $r^2_{ncv.}=0.941$) for rice plant exhibited a good correlation with steric (31.6%) and hydrophobic (39.7%) factors of the substrate molecules, and the model (B4: $r^2_{cv.}=0.569$ & $r^2_{ncv.}=0.941$) for barnyardgrass exhibited a good correlation with electrostatic (46.7%) and H-bond acceptor field (30.8%), respectively. The predicted $R_1=SF_5,\;R_2=R_3=R_4=H(P1)$ substituent (Rice plant: $pI_{50}=4.84$ & Barnyardgrass: $pI_{50}=7.21$, ${\Delta}pI_{50}=2.37$) by the model (B4) not only exhibited to the highest herbicidal activity against barnyardgrass, but also exhibited to the highest selecticity between two plants.