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Anomalous Enhancement of the Electrocatalytic Hydrogen Evolution Reaction in AuPt Nanoclusters

ACS Catalysis 2025年第11期15卷 9928-9939页

作者： Jiahui Kang Jan Kloppenburg Jiali Sheng Zhenyu Xu Kristoffer Meinander Hua Jiang Zhong-Peng Lv Esko I. Kauppinen Qiang Zhang Xi Chen Milla Vikberg Olli Ikkala Miguel A. Caro Bo Peng Department of Applied Physics Aalto University Espoo 02150 Finland Department of Chemistry and Materials Science Aalto University Espoo 02150 Finland Department of Bioproducts and Biosystems Aalto University Espoo 02150 Finland Department of Applied Physics Aalto University Espoo 02150 Finland；School of Physical Science and Technology Lanzhou University Lanzhou Gansu 730000 China；Lanzhou Center for Theoretical Physics and Key Laboratory for Quantum Theory and Applications of the Ministry of Education Lanzhou University Lanzhou Gansu 730000 China Department of Applied Physics Aalto University Espoo 02150 Finland；Department of Materials Science Advanced Coating Research Center of Ministry of Education of China Fudan University Shanghai 200433 China

Energy- and resource-efficient electrocatalytic water splitting is of paramount importance to enable hydrogen production. The best bulk catalyst for the hydrogen evolution reaction (HER), platinum, is one of the scarcest elements on Earth. The use of nanoclusters significantly reduces the amount of raw material required for HER, while nanoalloying further enhances performance by modulating hydrogen adsorption. However, the interplay between the atomic structure and HER performance in alloyed nanoclusters remains unclear. In this study, we report an anomalous HER enhancement at low and intermediate Au contents in monodisperse AuPt nanoclusters immobilized on carbon nanotubes. This enhancement is driven by the segregation of Au atoms toward the nanocluster surface and a synergistic effect, whereby the ability of surface Pt atoms to bind hydrogen is increased in the presence of adjacent Au atoms. This enhancement is noteworthy and “anomalous”, given that the overall hydrogen adsorption activity significantly decreases for pure Au nanoclusters compared to pure Pt nanoclusters. We rationalize these observations by combining extensive experimental characterization data with detailed atomistic simulations based on purpose-built machine learning interatomic potential and Markov-chain Monte Carlo simulations with variable chemical potential. The agreement between simulation and experiment allows us to develop a mechanistic understanding of the atomic-scale processes underlying the enhanced HER activity.

关键词： Nanoclusters

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Moving Object Localization Method Based on Single-Pixel Imaging in Complex Scenes

SSRN

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SSRN 2024年

作者： Zhang, Yanyan He, Ruiqing Zhang, Wenwen Kong, Tao Chen, Qian Li, Xiaoqian Advanced Interdisciplinary Research Center for Optics Nanjing University of Science and Technology Jiangsu Province Nanjing210094 China School of Information and Communication Engineering Nanjing Institute of Technology Jiangsu Province Nanjing211167 China

Single-pixel imaging (SPI) has received extensive attention in moving object tracking and localization, but most existing research studies lack discussion in complex scenes(grayscale changes continuously). To address this problem, this paper proposes a localization method of a moving object based on a SPI system in complex scenes. Firstly, based on the Fourier-slice theorem, several Fourier patterns are utilized to modulate the scene of the moving object, thereby obtaining the projection signals of the moving object in the horizontal and vertical directions. Then they are compared with the projection signals of the background to obtain the location information of the object. Simulation and experiments demonstrate that the proposed method can locate the moving object in complex scenes. In addition, the factors affecting the locating accuracy of this method are analyzed in the experiments. For scene with 256×256 resolution, this method only needs 0.02% sampling rate (21 frames) to locate the object, and the single localization only needs ∼1ms. This method promotes the application of SPI in moving object detection and other fields. © 2024, The Authors. All rights reserved.

关键词： Object detection

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Adaptive Block-Level Quality Parameter Adjustment Towards Low Video Bit-Rate Fluctuation

Adaptive Block-Level Quality Parameter Adjustment Towards Lo...

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IEEE Visual Communications and Image Processing (VCIP)

作者： Longtao Feng Qian Yin Huiwen Ren Zhao Wang Siwei Ma Yuwen He National Engineering Research Center of Visual Technology School of Computer Science Peking University China Advanced Institute of Information Technology Peking University China Bytedance Inc. San Diego CA USA

ISBN: (数字)9798331529543

ISBN: (纸本)9798331529550

Existing quantization parameter (QP) adjustment methods in video coding often focus solely on coding efficiency and ignore the impact of bit-rate fluctuations on video transmission and bandwidth waste. This is mainly because intra pictures, in a hierarchical coding structure, are allocated smaller QP and thus consume more bits. To address this issue, we propose an adaptive block-level QP adjustment method. Specifically, intra picture importance (IPI) is first introduced to evaluate the adjustability of intra picture QP. For intra pictures whose QP can be adjusted, we further propose block importance (BI) to determine their optimal block-level QP adjustment. Experimental results show that our proposed method reduce the bit-rate fluctuations while basically maintaining the coding performance. Notably, significant improvements can be observed in high-resolution videos, with a reduction of approximately 11% in bit-rate fluctuations.

关键词： Video coding Fluctuations Image coding Quantization (signal) Visual communication Bandwidth Encoding Motion compensation

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Quantitative noncontact measurement of thermal Hall angle and transverse thermal conductivity by lock-in thermography

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Physical Review applied 2025年第2期23卷 024018-024018页

作者： Takumi Imamura Takamasa Hirai Koichi Oyanagi Ryo Iguchi Kenta Takamori Satoru Kobayashi Ken-ichi Uchida Research Center for Magnetic and Spintronic Materials National Institute for Materials Science Tsukuba 305-0047 Japan Graduate School of Science and Technology University of Tsukuba Tsukuba 305-8573 Japan Faculty of Science and Engineering Iwate University Morioka 020-8551 Japan Department of Advanced Materials Science Graduate School of Frontier Sciences The University of Tokyo Kashiwa 277-8561 Japan

We propose and demonstrate a quantitative noncontact measurement method for the thermal Hall effect (THE) based on magnetic-field-modulated lock-in thermography (LIT). This method enables visualization of THE-induced temperature change and quantitative estimation of the thermal Hall angle θTHE by applying periodic magnetic fields to a sample and obtaining the first-harmonic response of thermal images. By combining this method with LIT-based measurement techniques for the longitudinal thermal conductivity κxx, we also quantify the transverse thermal conductivity κxy. We validate our measurement methods by estimating θTHE, κxx, and κxy in a ferromagnetic Heusler alloy Co2MnGa slab showing large THE.

关键词： Thermography (imaging)

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Preparation and Photoactive Characterization of Tube-shaped Al-doped ZnO Ceramics.

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MRS Online Proceedings Library 2021年第1期737卷 545-551页

作者： Yoshinobu Fujishiro M. Awano S. Kanzaki Synergy Materials Research Center National Institute of Advanced Industrial Science and Technology (AIST) Joint Research Center for Advanced Technology Nagoya Japan

Tubular Al-doped ZnO particles were prepared by homogeneous precipitation in the mixed solutions of Al(NO3)2, Zn(NO3)2, sodium dodecyl sulfate (SDS) surfactant and urea. At the molar ratio of Metal ions(Mt): SDS: urea: H2O is 1: 2: 20: 60, tubular products formed by heating at 80°C for 12 h. Plate like ZnO particles were obtained at Mt: SDS: urea: H2O = 1: 2: 10: 60 or 1: 1: 20: 60. The diameter of typical ZnO tube is ca.100 nm, and the length of tube is about 600nm (aspect ratio = 6). The relative surface area of tubular Al-doped ZnO is ca. 40.2 m2/g. The photo-decomposition rate of NO3- ions using tubular Al-doped ZnO particles was higher than standard TiO2 photo-catalysts (P-25) by irradiation >290nm light in 10mM KNO3-10vol%EtOH solutions at 30°C. The obtained materials showed DC conductive properties as compacted substrate by sintered at 400°C.

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Microwave-Assisted Seed Emulsion Polymerization Preparation of Snowman-Like Poly(Ionic Liquid) Microspheres

SSRN

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SSRN 2024年

作者： Yin, Jianbo Hu, Xufeng Li, Jingyi Zhao, Xiaopeng Smart Materials Laboratory Department of Applied Physics School of Physical Science and Technology Northwestern Polytechnical University Shaanxi Xi’an710129 China Research Center School of Physical Science and Technology Northwestern Polytechnical University Shaanxi Xi’an710129 China

Non-spherical particles (e.g. snowman-like) have different physical properties from spherical particles due to morphology effect and show great potential for applications in optics, magnetism, rheology, etc. In this paper, snowman-like poly(ionic liquid) microspheres are prepared by microwave-assisted seed emulsion polymerization. First, the cross-linked poly(ionic liquid) seed microspheres are prepared by post-drop addition method. Then, the seed microspheres are swollen by ionic liquid monomer to form a snowman shape. Finally, the snowman-shaped poly(ionic liquid) microspheres are obtained by microwave polymerization. The preparation process are traced by optical microscope and the morphology of snowman-like poly(ionic liquid) microspheres are observed by scanning electron microscope. It shows that, different from the preparation of snowman-like neutral polymer microspheres, the snowman-like morphology has been formed during swelling of cross-linked poly(ionic liquid) seed microspheres. The microwave-assisted polymerization can produce snowman-like poly(ionic liquid) microspheres with more uniform morphology compared to conventional heating polymerization. The morphology of snowman-like poly(ionic liquid) microspheres can be adjusted by controlling the monomer/seed microsphere ratio, size and cross-linking degree of cross-linked seed microspheres, and the concentration of monomers and seed microspheres. © 2024, The Authors. All rights reserved.

关键词： Microspheres

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Extended Axion Dark Matter Search Using the CAPP18T Haloscope

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Physical Review Letters 2023年第8期131卷 081801-081801页

作者： Byeongsu Yang Hojin Yoon Moohyun Ahn Youngjae Lee Jonghee Yoo Department of Physics and Astronomy Seoul National University Seoul 08826 Korea Department of Physics Korea Advanced Institute of Science and Technology Daejeon 34141 Korea Center for Axion and Precision Physics Research Institute for Basic Science Daejeon 34051 Korea

We report an extended search for the axion dark matter using the CAPP18T haloscope. The CAPP18T experiment adopts innovative technologies of a high-temperature superconducting magnet and a Josephson parametric converter. The CAPP18T detector was reconstructed after an unexpected incident of the high-temperature superconducting magnet quenching. The system reconstruction includes rebuilding the magnet, improving the impedance matching in the microwave chain, and mechanically readjusting the tuning rod to the cavity for improved thermal contact. The total system noise temperature is ∼0.6 K. The coupling between the cavity and the strong antenna is maintained at β≃2 to enhance the axion search scanning speed. The scan frequency range is from 4.8077 to 4.8181 GHz. No significant indication of the axion dark matter signature is observed. The results set the best upper bound of the axion-photon-photon coupling (gaγγ) in the mass ranges of 19.883 to 19.926 μeV at ∼0.7×|gaγγKSVZ| or ∼1.9×|gaγγDFSZ| with 90% confidence level. The results demonstrate that a reliable search of the high-mass dark matter axions can be achieved beyond the benchmark models using the technology adopted in CAPP18T.

关键词： Axions Electroweak interaction Hypothetical particle physics models Particle dark matter Particle interactions

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Promoting effect of d-band center and in-situ precipitation strategy on sulfur evolution reaction

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Journal of Energy Chemistry 2025年第5期104卷 740-748页

作者： Jun Pu Yun Tan Jiasen Yin Zihan Shen Shoujie Liu Kai Zhang Lei Zhou Yagang Yao Key Laboratory of Functional Molecular Solids Ministry of EducationAnhui Provincial Engineering Laboratory for New-Energy Vehicle Battery Energy-Storage MaterialsCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002AnhuiChina National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional MaterialsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093JiangsuChina State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Anhui UniversityHefei 230601AnhuiChina School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Department of Electrical Engineering Eindhoven University of TechnologyEindhoven MB 5600the Netherlands

The slow conversion of polyphase in lithium-sulfur(Li-S)batteries not only intensifies the shuttle effect of lithium polysulfides(LiPSs),but also causes the continuous accumulation of inactive sulfur species,resulting in rapid capacity attenuation and sluggish dynamic ***,the promoting effect of atomic interface stress on sulfur reaction was investigated via CoFe-CoFe_(2)O_(4)heterogeneous nanosheets with a cavity *** strain force induced by the in-situ precipitation of Co Fe bimetallic alloy in oxide matrix increased the d-band center,which was conducive to the interaction between catalyst and Li *** sulfur cathode based on this two-dimensional(2D)nanosheet design showed an extremely high capacity of 751 mAh g^(-1)at 4 *** with a sulfur loading of 5.55 mg cm^(-2),its area capacity was still as high as 7.15 mAh cm^(-2).Meanwhile,the enhanced stability greatly improved the practical potential of Li-S batteries.

关键词： 2D nanosheets In-situ precipitation Strain effect D-band center Li-S batteries

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Pre-existing chromatin accessibility of switchable repressive compartment delineates cell plasticity

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National science Review 2022年第6期9卷 100-113页

作者： Xiaolong Ma Xuan Cao Linying Zhu Ying Li Xuelong Wang Baihua Wu Gang Wei Lijian Hui State Key Laboratory of Cell Biology Shanghai Institute of Biochemistry and Cell Biology Center for Excellence in Molecular Cell Science Chinese Academy of Sciences University of Chinese Academy of Sciences CAS Key Laboratory of Computational Biology Shanghai Institute of Nutrition and Health Chinese Academy of SciencesUniversity of Chinese Academy of Sciences Institute for Stem Cell and Regeneration Chinese Academy of Sciences Bio-Research Innovation Center Shanghai Institute of Biochemistry and Cell Biology School of Life Science and Technology Shanghai Tech University School of Life Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences

Cell plasticity endows differentiated cells with competence to be reprogrammed to other lineages. Although extrinsic factors driving cell-identity conversion have been extensively characterized, it remains elusive which intrinsic epigenetic attributes, including high-order chromatin organization, delineate cell *** analysing the transcription-factor-induced transdifferentiation from fibroblasts to hepatocytes, we uncovered contiguous compartment-switchable regions(CSRs) as a unique chromatin unit. Specifically,compartment B-to-A CSRs, enriched with hepatic genes, possessed a mosaic status of inactive chromatin and pre-existing and continuous accessibility in fibroblasts. Pre-existing accessibility enhanced the binding of inducible factor Foxa3, which triggered epigenetic activation and chromatin interaction as well as hepatic gene expression. Notably, these changes were restrained within B-to-A CSR boundaries that were defined by CTCF occupancy. Moreover, such chromatin organization and mosaic status were detectable in different cell types and involved in multiple reprogramming processes, suggesting an intrinsic chromatin attribute in understanding cell plasticity.

关键词： cell plasticity intrinsic properties compartment-switchable regions mosaic status pre-existing accessibility hepatic transdifferentiation

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Short-term Weather Forecasting for Wind Energy Generation using A Deep Learning Technique 5

Short-term Weather Forecasting for Wind Energy Generation us...

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5th IEEE International Conference on Smart Systems and Technologies, SST 2022

作者： Zim, Abid Hasan Zeyad, Mohammad Ahmed, S.M. Masum Hossain, Eftakhar Energy and Technology Research Division Advanced Bioinformatics Computational Biology and Data Science Laboratory Bangladesh ABCD Laboratory Bangladesh Chattogram Bangladesh Heriot-Watt University Edinburgh United Kingdom University of Antwerp Faculty of Applied Engineering - Construction Antwerp Belgium

ISBN: (数字)9781665482158

ISBN: (纸本)9781665482158

Inadequate or erroneous weather predictions have a great impact on wind turbine energy output. Certain weather fluctuations and interruptions affect the efficient operation of wind turbines. Short-term weather predictions that are calibrated and verified make it simple to reduce the threat presented by meteorological uncertainty. Conventional physics-based techniques for forecasting are relatively weaker than data-driven approaches since wind turbine components usually have a multipart nonlinear relationship. Compared to physical methods, non-parametric alternatives like deep learning are thought to be more stable and lead to fewer mistakes in analyst predictions. This research presents the state-of-the-art Temporal Convolutional Network (TCN), one of the deep learning methods, which is introduced as a means of enhancing the precision of short-term forecasting of weather variables. TCN is an architecture that makes use of casual convolutions and dilations in order to be adaptable for sequential data with its temporality and huge receptive fields. Seven significant meteorological parameters from the NASA POWER dataset of Chouchala Sea Beach in Chittagong, Bangladesh, over a period of four months were used in this research. The accuracy was measured using Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE). The results obtained from the suggested TCN model demonstrate that the predicted outcome is pretty accurate and consistent. © 2022 IEEE.

关键词： Wind turbines

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