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991.
Sahng Hyuck Woo Nak Jun Lee Seung Ho Yook Hee Soo Kim Jieun Choi Jae-Hun Kim So Young Lee Jong Hyun Jang Sung Jong Yoo Young-Gi Yoon Jonghee Han Hyoung-Juhn Kim 《Advanced functional materials》2023,33(46):2305231
Although extensive research has been conducted, understanding the exact phenomena occurring during the operation of polymer electrolyte fuel cells (PEFCs) remains difficult. This research attempted to identify new reasons for the reduced performance of PEFC using an imaging technique. To begin with, H+ and OH− indicator sensors, which display red, blue, and green values (RGB) using digital microscopes, are developed and attached to each electrode of a membrane electrode assembly to enable quantitative analysis of ion generation. The proposed reaction in the fuel cell can be confirmed, and various reactions occurring in the electrode can be examined using this approach. In particular, H+ is generated at the anode and cathode of the anion exchange membrane fuel cell, which is found to be a major cause of performance deterioration. 相似文献
992.
Multi-branched gold nanoparticles were synthesized in high-yield through the reduction of HAuCl(4) by using hydrazine as a reducing agent. Practically 100% of the particles have numerous branches. The high reduction capability of hydrazine is found to be crucial for the formation of these branched gold nanoparticles. Their size can be controlled from 20 to 130 nm by varying the amounts of hydrazine. The prepared nanoparticles exhibit efficient surface-enhanced Raman scattering (SERS) properties and the SERS activity of the particles depends on the aspect ratio of their branches, which are most likely related to a great increase in the localized electromagnetic field enhancement from their unique sharp surface features arising from the branches. 相似文献
993.
A novel linear switched termination active cross‐coupled low‐voltage differential signaling (LVDS) transceiver operating at 1.5 GHz clock frequency is presented. On the transmitter side, an active cross‐coupled linear output driver and a switched termination scheme are applied to achieve high speed with low current. On the receiver side, a shared preamplifier scheme is employed to reduce power consumption. The proposed LVDS transceiver implemented in an 80 nm CMOS process is successfully demonstrated to provide a data rate of 6 Gbps/pin, an output data window of 147 ps peak‐to‐peak, and a data swing of 196 mV. The power consumption is measured to be 4.2 mW/pin at 1.2 V. 相似文献
994.
Young Kwon song 《代数通讯》2013,41(4):1649-1663
Maximal commutative subalgebras of the algebra of n by n matrices over a field k very rarely have dimension smaller than n. There is a (B, N)-construction which yields subalgebras of this kind. The Courter's algebra that is of this kind was shown a (B, N)-construction where B is the Schur algebra of size 4 and N = k 4. That is, the Courter's algebra is isomorphic to B ? (k 4)2, the idealization of (k 4)2. It was questioned how many isomorphism classes can be produced by varying the finitely generated faithful B-module N. In this paper, we will show that the set of all algebras B ? N 2 fall into a single isomorphism class, where B is the Schur algebra of size 4 and N a finitely generated faithful B-module. 相似文献
995.
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997.
Hwang SH Song J Jung Y Kweon OY Song H Jang J 《Chemical communications (Cambridge, England)》2011,47(32):9164-9166
Novel ZnO/TiO(2) composite nanofibers were fabricated by an electrospinning method and showed excellent antimicrobial activity against gram-negative Escherichia coli and gram-positive Staphylococcus aureus under UV irradiation and in the absence of light. 相似文献
998.
Hyung‐Kyu Lim Young Sun Choi Seung‐Tae Hong 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(6):i36-i38
The previously unknown crystal structure of magnesium perchlorate anhydrate, determined and refined from laboratory X‐ray powder diffraction data, represents a new structure type. The title compound was obtained by heating magnesium perchlorate hexahydrate at 523 K for 2 h under vacuum and it crystallizes in the monoclinic space group P21/c. The asymmetric unit contains one Mg (site symmetry on special position 2a), one Cl and four O sites (on general positions 4e). The structure consists of a three‐dimensional network resulting from the corner‐sharing of MgO6 octahedra and ClO4 tetrahedra. Each MgO6 octahedron share corners with six ClO4 tetrahedra. Each ClO4 tetrahedron shares corners with three MgO6 octahedra, with one O‐atom corner dangling. The ClO4 tetrahedra are oriented in such a way that one‐dimensional channels parallel to [100] are formed between the dangling O atoms. 相似文献
999.
Pan Wang Dr. Jian-Wei Wang Prof. Wen-Hua Zhang Dr. Hongzhen Bai Prof. Guping Tang Prof. David J. Young 《化学:亚洲杂志》2021,16(19):2993-3000
Nanoformulations of mononuclear Pt complexes cis-PtCl2(PPh3)2 ( 1 ), [Pt(PPh3)2(L−Cys)] ⋅ H2O ( 3 , L−Cys=L-cysteinate), trans-PtCl2(PPh2PhNMe2)2 ( 4 ; PPh2PhNMe2=4-(dimethylamine)triphenylphosphine), trans-PtI2(PPh2PhNMe2)2 ( 5 ) and dinuclear Pt cluster Pt2(μ-S)2(PPh3)4 ( 2 ) have comparable cytotoxicity to cisplatin against murine melanoma cell line B16F10. Masking of these discrete molecular entities within the hydrophobic core of Pluronic® F-127 significantly boosted their solubility and stability, ensuring efficient cellular uptake, giving in vitro IC50 values in the range of 0.87–11.23 μM. These results highlight the potential therapeutic value of Pt complexes featuring stable Pt−P bonds in nanocomposite formulations with biocompatible amphiphilic polymers. 相似文献
1000.
In this paper, first we introduce a new notion of commuting condition that φφ 1 A = A φ 1 φ between the shape operator A and the structure tensors φ and φ 1 for real hypersurfaces in G 2(? m+2). Suprisingly, real hypersurfaces of type (A), that is, a tube over a totally geodesic G 2(? m+1) in complex two plane Grassmannians G 2(? m+2) satisfy this commuting condition. Next we consider a complete classification of Hopf hypersurfaces in G 2(? m+2) satisfying the commuting condition. Finally we get a characterization of Type (A) in terms of such commuting condition φφ 1 A = A φ 1 φ. 相似文献