http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Choi, Mihwa,Ahn, Chi-Yeong,Lee, Hyunjoon,Kim, Jong Kwan,Oh, Seung-Hyeon,Hwang, Wonchan,Yang, Seugran,Kim, Jungsuk,Kim, Ok-Hee,Choi, Insoo,Sung, Yung-Eun,Cho, Yong-Hun,Rhee, Choong Kyun,Shin, Woonsup Elsevier 2019 Applied Catalysis B Vol.253 No.-
<P><B>Abstract</B></P> <P>Formic acid is a chemical with a simple molecular structure containing hydrogen. This liquid at room temperature is easy to handle and has a low toxicity, and is thus in the spotlight as a fuel. In particular, formic acid is an excellent fuel candidate because it can be operated at low temperatures when applied as a fuel in fuel cells with a high theoretical open-circuit voltage (1.48 V). However, it has a drawback in that the electrode catalyst is deactivated due to the generation of CO intermediates when formic acid is oxidized during cell operation. Therefore, to prevent this, an irreversibly adsorbed Bi on Pt catalyst is applied to a direct formic acid fuel cell (DFAFC) anode because it is easy to synthesize and economical. Physical analyses such as transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were conducted, and electrochemical evaluations were performed through half-cell and single-cell level tests. The results revealed that the formic acid oxidation reaction activity of the Bi-modified Pt/C was 13 times higher than that of the conventional catalyst at 0.58 V. Further, a DFAFC stack was fabricated using the Bi-modified Pt/C, which yielded a power of 300 W. These results suggest that a simple synthesis method can be applied to fabricating industrially available DFAFC stacks.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bi-modified Pt catalyst is applied to a direct formic acid fuel cell (DFAFC) anode. </LI> <LI> Bi was irreversibly adsorbed on Pt catalyst by a simple synthetic strategy. </LI> <LI> Bi-modified Pt/C showed significantly high formic acid oxidation reaction activity. </LI> <LI> A DFAFC stack fabricated using Bi-modified Pt/C yielded a power of 300 W. </LI> <LI> The simple synthetic strategy can be applied to achieving DFAFC stacks commercially. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Choi, Min-Yeol,Choi, Dukhyun,Jin, Mi-Jin,Kim, Insoo,Kim, Sang-Hyeob,Choi, Jae-Young,Lee, Sang Yoon,Kim, Jong Min,Kim, Sang-Woo WILEY-VCH Verlag 2009 ADVANCED MATERIALS Vol.21 No.21
<B>Graphic Abstract</B> <P>Transparent flexible charge-generating piezoelectric nanodevices are developed. The resulting integrated nanodevice generates a noticeable current when it is pushed by application of an external load. Piezoelectric ZnO nanorod-based nanodevices with embossed PdAu top electrodes produce the highest output current density of approximately 10 μA cm<SUP>−2</SUP> at a load of 0.9 kgf. <img src='wiley_img/09359648-2009-21-21-ADMA200803605-content.gif' alt='wiley_img/09359648-2009-21-21-ADMA200803605-content'> </P>
Fabrication of copper nanoparticles in a thick polyimide film cured by rapid thermal annealing.
Choi, Min Young,Choi, Dong Joo,Ahn, Key-One,Ro, Insoo,Kim, Young-Ho,Suh, Sang-Hee American Scientific Publishers 2012 Journal of Nanoscience and Nanotechnology Vol.12 No.4
<P>We investigated the imidization of a polyimide (PI) and the formation of Cu nanoparticles in a PI film by curinga precursor of PI (polyamic acid (PAA) dissolved in n-methyl-2-pyrrolidinone) in a reducing atmosphere in the rapid thermal annealing (RTA) system. A Cu film was deposited onto the SiO2/Si substrate, and the PAA was spin-coated onto the Cu film. After the PAA reacted with the Cu film, soft-baking was performed to evaporate the solvent. Finally, the PAA was imidized to PI at 450 degrees C by curing in a reducing atmosphere with the RTA. Fourier transform infrared spectroscopy showed that the PAA was successfully imidized by the RTA. X-ray diffraction patterns revealed that Cu nanoparticles formed by RTA curing at 450 degrees C for 5 minutes in a reducing atmosphere, and transmission electron microscopy showed that Cu nanoparticles about 6.5 nm in size were uniformly dispersed in the PI film. Curing by RTA is an attractive method because it takes only a few minutes.</P>
Choi, Insoo,Lim, Dong-Hee,Shin, Dong Yun Elsevier 2018 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY - Vol.43 No.24
<P><B>Abstract</B></P> <P>Highly dispersed Pt<SUB>shell</SUB>-Pd<SUB>core</SUB> catalyst is synthesized via an electroless deposition and a galvanic displacement. From electrochemical analysis, the catalyst is confirmed to be active toward an ethanol oxidation reaction for a prolonged time, and is more resistive against CO<SUB>ad</SUB>-poisoning than a conventional Pt/C catalyst. The stable activity of Pt<SUB>shell</SUB>-Pd<SUB>core</SUB>/C is ascribed to the modified electronic property of Pt over-layer, which leads to a weak CO-adsorption strength with a high affinity for OH. The weakened binding property of surface Pt with CO<SUB>ad</SUB> was experimentally confirmed by conducting a CO<SUB>ad</SUB>-stripping and by measuring an electrochemically active surface area of the catalyst over multiple cycles. The CO<SUB>ad</SUB> oxidation ability of as-synthesized catalyst is further proved by a computational method via density functional theory (DFT) calculation. The result presents a potential application of the catalyst for the efficient ethanol oxidation in a direct ethanol fuel cell.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Pt<SUB>shell</SUB>-Pd<SUB>core</SUB>/C catalyst was synthesized by electroless deposition and displacement. </LI> <LI> The catalyst is more active in ethanol oxidation reaction than commercial Pt catalyst. </LI> <LI> The catalyst showed moderate CO<SUB>ad</SUB>-tolerance and long-term durability. </LI> <LI> The stable activity was ascribed to the modified electronic property of the catalyst. </LI> <LI> The higher CO oxidation capacity was supported by density functional theory. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>A Pt<SUB>shell</SUB>-Pd<SUB>core</SUB>/C catalyst was electrochemically synthesized, and exhibited higher catalytic activity with CO<SUB>ad</SUB>-tolerance toward ethanol oxidation at prolonged time. The core-shell configuration induced the change in the binding ability of catalyst with adsorbate, which ultimately increased its CO oxidation capacity.</P> <P>[DISPLAY OMISSION]</P>
Insoo Choi(최인수),Yong-Chul Kim(김용철) 한국생명과학회 2008 생명과학회지 Vol.18 No.4
본 연구는 콩의 Glycine tomentella와 G. max 뱀콩의 종간교잡으로부터 얻은 F₁식물체의 검증을 위하여 형태적, 세포 유전학적, 그리고 분자유전학적 연구를 하였던 바 그 결과를 요약하면 다음과 같다. F₁ 식물체의 암술과 수술, 꽃 색깔, 그리고 생육습관 등의 형태적 특징들은 G. tomentella 의 특징들을 따르거나 중간적 특성을 나타내었다. G. tomentella (2n=38) 와 G. max 뱀콩(2n=40)의 F₁식물체의 염색체수는 2n=39를 가지고 있었다. Esterase와 peroxidase의 동위효소 반응의 결과에서도 F₁ 식물체는 G. tomentella과 G. max 뱀콩의 중간적인 밴드유형을 나타내었다. RAPD 분석결과 62 primers들로부터 얻은 F₁ 식물체 밴드양상이 모두 G. tomentella와 G. max 뱀콩 양친으로부터 물려받은 것들로 판명되었다. 형태적, 세포학적 그리고 분자유전학적 결과들을 종합하여 볼 때, 본 연구의 G. max와 G. tomentella의 종간교잡으로부터 얻은 F₁ 식물체는 진정 F₁ 교배체로 판명되었다. F₁ 식물체의 임성회복을 위한 연구와 RAPD 분석에서 나타난 모계유전양상(OPA02, OPA09)과 부계유전양상(OPD05)을 보인 결과에 대한 지속적인 연구를 위한 노력이 요구된다. This study was carried out to demonstrate morphological, cytological and molecular evidence for intersubgeneric F₁ hybrid between Glycine tomentella and G. max cv. 'Baemkong'. Morphological features of F₁ plant for pistil and stamen, flower color and growth habit showed intermediate type between G. tomentella and G. max cv. 'Baemkong'. Chromosome number of F₁ plant was 2n=39, which explained the evidence of F₁ hybrid between G. tomentella (2n=38) and G. max cv. 'Baemkong' (2n=40). Polyacrylamide isoelectric focusing pattern for esterase and peroxidase also showed that the F₁ plant was true F₁ hybrid between G. tomentella and G. max cv. 'Baemkong'. From RAPD analysis, we identified that 62 primers showing bands in F₁ hybrid had both bands from G. tomentella and G. max cv. 'Baemkong', which suggested that this was true F₁ hybrid. Based on our results from morphological, cytological and molecular analyses, we suggest that the F₁ plant was true intersubgeneric hybrid between G. tomentella and G. max cv. 'Baemkong'. Our results still remain us further study to recover fertility of F₁ hybrids. The occurrence of maternal and/or paternal inheritance in F₁ hybrid from intersubgeneric cross between G. tomentella and G. max cv. 'Baemkong' need to be explained.
Choi, Insoo,Kim, Hak-Yoon,Ahn, Sang Hyun,Hwang, Seung Jun,Yoo, Sung Jong,Kim, Ho Young,Choi, Jihui,Park, Hyan Joo,Jang, Jong Hyun,Kim, Soo-Kil American Scientific Publishers 2016 Journal of Nanoscience and Nanotechnology Vol.16 No.10
<P>Electrochemical conversion of carbon dioxide to formic acid was attempted on Sn-Zn alloy catalysts. The alloy catalysts were fabricated by electrodeposition, and their compositions were controlled by varying the concentration of the precursor solution. A home made proton exchange membrane-based electrochemical cell was used for the reduction of carbon dioxide. The concentration of formic acid produced and the conversion efficiency were determined via electrolysis and high performance liquid chromatography analysis. The effect of the alloy composition on the amount of formic acid generated and the conversion efficiency was evaluated, and alloy composition was found to have a strong influence on these variables. It was thus concluded that the conversion of carbon dioxide to formic acid can be enhanced by alloying Zn with Sn.</P>