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排序方式: 共有3105条查询结果,搜索用时 15 毫秒
1.
N. Clament Sagaya Selvam Lijie Du Bao Yu Xia Pil J. Yoo Bo You 《Advanced functional materials》2021,31(12):2008190
Electroreduction of small molecules such as H2O, CO2, and N2 for producing clean fuels or valuable chemicals provides a sustainable approach to meet the increasing global energy demands and to alleviate the concern on climate change resulting from fossil fuel consumption. On the path to implement this purpose, however, several scientific hurdles remain, one of which is the low energy efficiency due to the sluggish kinetics of the paired oxygen evolution reaction (OER). In response, it is highly desirable to synthesize high-performance and cost-effective OER electrocatalysts. Recent advances have witnessed surface reconstruction engineering as a salient tool to significantly improve the catalytic performance of OER electrocatalysts. In this review, recent progress on the reconstructed OER electrocatalysts and future opportunities are discussed. A brief introduction of the fundamentals of OER and the experimental approaches for generating and characterizing the reconstructed active sites in OER nanocatalysts are given first, followed by an expanded discussion of recent advances on the reconstructed OER electrocatalysts with improved activities, with a particular emphasis on understanding the correlation between surface dynamics and activities. Finally, a prospect for clean future energy communities harnessing surface reconstruction-promoted electrochemical water oxidation will be provided. 相似文献
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Yang Liu Vladimir Motalov Stefan Baumann Dmitry Sergeev Michael Müller Yoo Jung Sohn Olivier Guillon 《Journal of the European Ceramic Society》2019,39(15):4874-4881
The materials typically used for oxygen transport membranes, Ba0.5Sr0.5Co0.8Fe0.2O3?δ (BSCF) and La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) tend to decompose due to their low thermochemical stability under reducing atmosphere. Fe- and Co-doped SrTiO3 (SrTi1-x-yCoxFeyO3-δ, x + y ≤ 0.35) (STCF) materials showing an oxygen transport comparable to LSCF have great potential for application in ion-transport-devices. In this study, the thermochemical stability of pure perovskite-structured STCF was investigated after annealing in a syngas atmosphere at 600–900 °C. The phase composition of the materials after annealing was characterized by means of X-ray diffraction (XRD). The thermodynamic activities of SrO, FeO, and CoO in the STCF materials were evaluated using Knudsen effusion mass spectrometry (KEMS). Co-doped SrTiO3 (STC) materials were not stable after annealing in the syngas atmosphere above 5 mol% Co-substitution. Ruddlesden-Popper-like phases and SrCO3 were detected after annealing at 600 °C. In contrast, Fe substitution (STF) showed good stability after annealing in syngas upto 35 mol% substitution. 相似文献
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Wireless Networks - A novel approach is proposed to detect protocol misbehavior using state-of-the-art machine learning frameworks and entropy. Nodes in Vehicular Ad Hoc Networks (VANETs) use... 相似文献
5.
Hong Kyoung Seong Cheol Woong Kim Jeonghoon Yoo Jaewook Lee 《International journal for numerical methods in engineering》2019,119(5):334-360
In this study, a multimaterial topology optimization method using a single variable is proposed by combining the solid isotropic material with penalization method and the reaction-diffusion equation. Unlike ordinary multimaterial optimization, which requires several variables depending on the number of material types, this method intends to represent various materials as one variable. The proposed method combines two special functions in the sensitivity analysis of the objective function to converge the design variable into prespecified density values defined for each of the multimaterials. The composition constraint based on a normal distribution function is also introduced to estimate the distribution of each target density value in a single variable. It enables density exchange between multiple materials by increasing or decreasing the amount of a specific material. The proposed method is applied to structural and electromagnetic problems to verify its effectiveness, and its usefulness is also confirmed from the viewpoint of cost and computation time. 相似文献
6.
Jeong Ji-Seong Song Min-Ho Lee Sang-Ho Kim Mihye Baek Nakhoon Yoo Kwan-Hee 《The Journal of supercomputing》2019,75(8):4505-4518
The Journal of Supercomputing - This paper presents a web-based three-dimensional (3D) navigation system for a spinal disease ontology using a 3D virtual human spine. The 3D navigation system... 相似文献
7.
Jae Won Kim S. P. Murugan Ji-Hong Yoo R. Ashiri 《Science & Technology of Welding & Joining》2020,25(3):235-242
ABSTRACTThis paper presents an innovative approach that uses a pulse-profile to improve the welding quality of CP1180 steel in resistance spot welding process. Three pulses with two cooling times were used in the developed multi-pulse welding (MPW) schedule. The experimental results show that the first pulse increases the contact area between the sheets to improve the current flow pattern. The second pulse was designed to extend the sheet-to-sheet contact area and corona bond for preventing rapid nugget growth. Using these designs, the nugget size was maximised through the third pulse. The maximum nugget size using the designed MPW schedule was 18.5% greater than that of the single-pulse welding schedule and the weldable current range was extended by 130%. 相似文献
8.
Chang-Kyu Heo Hai-Min Hwang Won-Hee Lim Hye-Jung Lee Jong-Shin Yoo Kook-Jin Lim Eun-Wie Cho 《International journal of molecular sciences》2020,21(24)
Tumor-associated (TA) autoantibodies have been identified at the early tumor stage before developing clinical symptoms, which holds hope for early cancer diagnosis. We identified a TA autoantibody from HBx-transgenic (HBx-tg) hepatocellular carcinoma (HCC) model mouse, characterized its target antigen, and examined its relationship to human HCC. The mimotopes corresponding to the antigenic epitope of TA autoantibody were screened from a random cyclic peptide library and used for the detection of serum TA autoantibody. The target antigen of the TA autoantibody was identified as an oncogenic bi-functional purine biosynthesis protein, ATIC. It was upregulated in liver cancer tissues of HBx-tg mouse as well as human HCC tissues. Over-expressed ATIC was also secreted extracellularly via the cancer-derived exosomes, which might cause auto-immune responses. The cyclic peptide mimotope with a high affinity to anti-ATIC autoantibody, CLPSWFHRC, distinguishes between serum samples from HCC patients and healthy subjects with 70.83% sensitivity, 90.68% specificity (AUC = 0.87). However, the recombinant human ATIC protein showed a low affinity to anti-ATIC autoantibody, which may be incompatible as a capture antigen for serum TA autoantibody. This study indicates that anti-ATIC autoantibody can be a potential HCC-associated serum biomarker and suggests that autoantibody biomarker’s efficiency can be improved by using antigenic mimicry to native antigens present in vivo. 相似文献
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Multimedia Tools and Applications - Recently, various query processing schemes in mobile environments have been studied. Particularly, a reverse skyline query that is the variation of a skyline... 相似文献