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Influences of Co-Flow and Counter-Flow Modes of Reactant Flow Arrangement on a PEMFC at Start-Up

Computer Modeling in Engineering & Sciences 2024年第5期139卷 1337-1356页

作者： Qianqian shao Min Wang Nuo Xu School of Petroleum Engineering Guangdong University of Petrochemical TechnologyMaoming525000China Mechanics Division Beijing Computational Science Research CenterBeijing100193China

To investigate the influences of co-flowand counter-flowmodes of reactant flowarrangement on a proton exchange membrane fuel cell(PEMFC)during start-up,unsteady physical and mathematical models fully coupling the flow,heat,and electrochemical reactions in a PEMFC are *** continuity equation and momentum equation are solved by handling pressure-velocity coupling using the SIMPLE *** electrochemical reaction rates in the catalyst layers(CLs)of the cathode and anode are calculated using the Butler-Volmer *** multiphase mixture model describes the multiphase transport process of gas mixtures and liquid water in the fuel *** validation,the influences of co-flow and counter-flow modes on the PEMFC performance are investigated,including the evolution of the current density,flow field,temperature field,and reactant concentration field during start-up,as well as the steady distribution of the current density,reactant concentration,andmembrane water content when the start-up ***-flow and counter-flow modes influence the current density distribution and temperature *** the one hand,the co-flow mode accelerates the start-up process of the PEMFC and leads to a more evenly distributed current density than the counter-flow *** the other hand,the temperature difference between the inlet and outlet sections of the cell is up to 10.1℃ under the co-flow mode,much larger than the 5.0℃ observed in the counter-flow ***,the counter-flowmode results in a more evenly distributed temperature and a lower maximum temperature than the co-flow ***,in the flow field design of a PEMFC,the reactant flow arrangements can be considered to weigh between better heat management and higher current density distribution of the cell.

关键词： PEMFC full coupling model Butler-Volmer equation multiphase mixture model co-flow mode counter-flow mode

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Superhydrophobic Surface-Assisted Preparation of Microspheres and Supraparticles and Their Applications

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Nano-Micro Letters 2024年第4期16卷 110-138页

作者： Mengyao Pan Huijuan shao Yue Fan Jinlong Yang Jiaxin Liu Zhongqian Deng Zhenda Liu Zhidi Chen Jun Zhang Kangfeng yi Yucai Su Dehui Wang Xu Deng Fei Deng Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 611731People’s Republic of China School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275People’s Republic of China Shenzhen Institute for Advanced Study University of Electronic Science and Technology of ChinaShenzhen 518110People’s Republic of China Pharmaceutical Glass Co.Ltd Zibo 256100People’s Republic of China Department of Nephropathy School of MedicineSichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduPeople’s Republic of China Department of Nephrology Sichuan Provincial People’s Hospital Jinniu HospitalChengdu Jinniu District People’s HospitalChengduPeople’s Republic of China

Superhydrophobic surface(SHS) has been well developed, as SHS renders the property of minimizing the water/solid contact interface. Water droplets deposited onto SHS with contact angles exceeding 150°, allow them to retain spherical shapes, and the low adhesion of SHS facilitates easy droplet collection when tilting the substrate. These characteristics make SHS suitable for a wide range of applications. One particularly promising application is the fabrication of microsphere and supraparticle materials. SHS offers a distinct advantage as a universal platform capable of providing customized services for a variety of microspheres and supraparticles. In this review, an overview of the strategies for fabricating microspheres and supraparticles with the aid of SHS, including cross-linking process, polymer melting,and droplet template evaporation methods, is first presented. Then, the applications of microspheres and supraparticles formed onto SHS are discussed in detail, for example, fabricating photonic devices with controllable structures and tunable structural colors, acting as catalysts with emerging or synergetic properties, being integrated into the biomedical field to construct the devices with different medicinal purposes, being utilized for inducing protein crystallization and detecting trace amounts of analytes. Finally,the perspective on future developments involved with this research field is given, along with some obstacles and opportunities.

关键词： Superhydrophobic surface Microspheres and supraparticles Photonic devices Catalysts Biomedical and trace detections

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A SIMPLE ITERATIVE ALGORITHM FOR MAXCUT

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Journal of Computational Mathematics 2024年第5期42卷 1277-1304页

作者： Sihong shao Dong Zhang Weixi Zhang CAPT LMAM and School of Mathematical SciencesPeking UniversityBeijing 100871China LMAM and School of Mathematical Sciences Peking UniversityBeijing 100871China

We propose a simple iterative(SI)algorithm for the maxcut problem through fully using an equivalent continuous *** does not need rounding at all and has advantages that all subproblems have explicit analytic solutions,the cut values are monotonically updated and the iteration points converge to a local optima in finite steps via an appropriate subgradient *** experiments on G-set demonstrate the *** particular,the ratios between the best cut values achieved by SI and those by some advanced combinatorial algorithms in[***.,2.8(2.17),365-403]are at least 0.986 and can be further improved to at least 0.997 by a preliminary attempt to break out of local optima.

关键词： Maxcut Iterative algorithm Exact solution Subgradient selection Fractional programming

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Advancements in Remote Sensing Image Dehazing: Introducing URA-Net with Multi-Scale Dense Feature Fusion Clusters and Gated Jump Connection

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2397-2424页

作者： Hongchi Liu Xing Deng Haijian shao School of Computer Jiangsu University of Science and TechnologyZhenjiang212003China Department of Electrical and Computer Engineering University of NevadaLas Vegas89119USA

The degradation of optical remote sensing images due to atmospheric haze poses a significant obstacle,profoundly impeding their effective utilization across various *** methodologies have emerged as pivotal components of image preprocessing,fostering an improvement in the quality of remote sensing *** enhancement renders remote sensing data more indispensable,thereby enhancing the accuracy of target *** defogging techniques based on simplistic atmospheric degradation models have proven inadequate for mitigating non-uniform haze within remotely sensed *** response to this challenge,a novel UNet Residual Attention Network(URA-Net)is *** paradigmatic approach materializes as an end-to-end convolutional neural network distinguished by its utilization of multi-scale dense feature fusion clusters and gated jump *** essence of our methodology lies in local feature fusion within dense residual clusters,enabling the extraction of pertinent features from both preceding and current local data,depending on contextual *** intelligently orchestrated gated structures facilitate the propagation of these features to the decoder,resulting in superior outcomes in haze *** validation through a plethora of experiments substantiates the efficacy of URA-Net,demonstrating its superior performance compared to existing methods when applied to established datasets for remote sensing image *** the RICE-1 dataset,URA-Net achieves a Peak Signal-to-Noise Ratio(PSNR)of 2..07 dB,surpassing the Dark Channel Prior(DCP)by 11.17 dB,the All-in-One Network for Dehazing(AOD)by 7.82.dB,the Optimal Transmission Map and Adaptive Atmospheric Light For Dehazing(OTM-AAL)by 5.37 dB,the Unsupervised Single Image Dehazing(USID)by 8.0 dB,and the Superpixel-based Remote Sensing Image Dehazing(SRD)by 8.5 *** noteworthy,on the SateHaze1k dataset,URA-Net attains preeminence in overall performance,yieldi

关键词： Remote sensing image image dehazing deep learning feature fusion

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An M-VCUT level set-based data-driven model of microstructures and optimization of two-scale structures

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Frontiers of Mechanical Engineering 2024年第4期19卷 73-86页

作者： Minjie shao Tielin SHI Qi XIA State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

The optimization of two-scale structures can adapt to the different needs of materials in various regions by reasonably arranging different microstructures at the macro scale,thereby considerably improving structural ***,a multiple variable cutting(M-VCUT)level set-based data-driven model of microstructures is presented,and a method based on this model is proposed for the optimal design of two-scale *** geometry of the microstructure is described using the M-VCUT level set method,and the effective mechanical properties of microstructures are computed by the homogenization ***,a database of microstructures containing their geometric and mechanical parameters is *** two sets of parameters are adopted as input and output datasets,and a mapping relationship between the two datasets is established to build the data-driven model of *** the optimization of two-scale structures,the data-driven model is used for macroscale finite element and sensitivity *** efficiency of the analysis and optimization of two-scale structures is improved because the computational costs of invoking such a data-driven model are much smaller than those of homogenization.

关键词： two-scale structure structural optimization M-VCUT level set homogenization radial basis function data-driven

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The metabolic profiling of Chinese yam fermented by Saccharomyces boulardii and the biological activities of its ethanol extract in vitro

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Food Science and Human Wellness 2024年第5期13卷 2718-2726页

作者： Xue Li yiwen shao Limin Hao Qiaozhen Kang Xiaolong Wang Jiaqing Zhu Changcheng Zhao Yanling Shi Jike Lu Juanjuan yi School of Life Sciences Zhengzhou UniversityZhengzhou 450001China Food Laboratory of Zhongyuan Zhengzhou UniversityLuohe 462300China Systems Engineering Institute Academy of Military Sciences(AMS)Beijing 100010China Henan yinfeng Biological Engineering Technology Co. Ltd.Zhengzhou 450000China

Chinese yam(Dioscorea opposita Thunb.),as one of the medicinal and edible homologous plants,is rich in various nutrients and functional *** this study,Chinese yam fermented by Saccharomyces boulardii was performed to investigate its bioactive components and metabolic *** then,the main bioactive components and biological activities of fermented Chinese yam ethanol extract(FCYE)were *** showed that there were 49 up-regulated metabolites and 52.down-regulated metabolites in fermented Chinese yam compared to unfermented Chinese ***,corresponding metabolic pathways analysis initially revealed that the distribution of bioactive substances was concentrated on alcoholsoluble small molecular ***,the total polyphenol content and the total flavonoid content in FCYE were significantly increased,and the corresponding antioxidant and immunomodulatory activities in vitro were also significantly *** study provided a new reference for the comprehensive utilization of Chinese yam and laid a theoretical foundation for the development and application of natural probiotic-fermented products.

关键词： Chinese yam Saccharomyces boulardii Metabolites Antioxidant Immunomodulation

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费雪货币论述与清代北京虚数钱计物价

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清华大学学报（哲学社会科学版） 2024年第2期39卷 201-217,240页

作者：邵义中国香港999077

清代北京流通的钱币主要有制钱、当十钱和当十铜元。这三种不同钱币流通的时间分别为1644年—1856年、1853年—1907年、1901年—1935年。如何将历史文献中的钱计物价折合成当时流通钱币的文数并非易事,其原因是清代北京的钱计物价有虚... 详细信息

清代北京流通的钱币主要有制钱、当十钱和当十铜元。这三种不同钱币流通的时间分别为1644年—1856年、1853年—1907年、1901年—1935年。如何将历史文献中的钱计物价折合成当时流通钱币的文数并非易事,其原因是清代北京的钱计物价有虚实之分。北京的虚数物价具有以下的特征:第一,当制钱流通时,1文制钱作虚数2.,虚数1吊钱等于500文制钱;第二,咸丰七年至光绪三十一年,1枚当十钱作虚数2.文,虚数1吊钱等于50枚当十钱;第三,光绪三十一年后,1枚当十铜元文作虚数100文,虚数1吊钱折合10枚当十铜元;第四,文献中虚数与实数的出现毫无规律可言。与以往的研究不同,运用费雪的货币论述可证明清代北京物价虚数的产生与演变,很可能是朝廷决策的经济后果。

关键词：清代北京虚数物价制钱京钱费雪

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Shor's algorithm does not factor large integers in the presence of noise

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Science China(Information Sciences) 2024年第7期67卷 305-320页

作者： Jin-yi CAI College of Letters and Science University of Wisconsin

We consider Shor's quantum factoring algorithm in the setting of noisy quantum gates. Under a generic model of random noise for(controlled) rotation gates, we prove that the algorithm does not factor integers of the form pq when the noise exceeds a vanishingly small level in terms of n—the number of bits of the integer to be factored, where p and q are from a well-defined set of primes of positive density. We further prove that with probability 1-o(1) over random prime pairs(p, q), Shor's factoring algorithm does not factor numbers of the form pq, with the same level of random noise present.

关键词： random noise Shor’s algorithm rotation gates quantum computing prime factorization

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Black holes as the source of dark energy:A stringent test with high-redshift JWST AGNs

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 181-188页

作者： Lei Lei Lei Zu Guan-Wen Yuan Zhao-Qiang Shen yi-ying Wang Yuan-Zhu Wang Zhen-Bo Su Wen-Ke Ren {2.-Peng Tang Hao Zhou Chi Zhang Zhi-Ping Jin Lei Feng yi-Zhong Fan Da-Ming Wei Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China

Studies have proposed that there is evidence for cosmological coupling of black holes(BHs)with an index of k≈3;hence,BHs serve as the astrophysical source of dark ***,the data sample is limited for the redshifts of≤*** recent years,the James Webb Space Telescope(JWST)has detected many high-redshift active galactic nuclei(AGNs)and *** the JWST NIRSpec-/NIRCam-resolved AGNs,three are determined to be in early-type host galaxies with a redshift of z~***,their M_(*)and MBH are in tension with the predicted cosmological coupling of black holes with k=3 at a confidence level of~2.,which challenges the hypothesis that BHs serve as the origin of dark *** work on high-redshift AGNs using the JWST will further assess such a hypothesis by identifying more early-type host galaxies in the higher mass range.

关键词： dark energy supermassive black hole active galactic nuclei James Webb Space Telescope

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NFT交易的法律意涵及其规制路径

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暨南学报（哲学社会科学版） 2024年第8期46卷 50-64页

作者：邵怿北京化工大学文法学院南方科技大学廉洁研究院

NFT自其诞生伊始就受到了市场与资本的追捧,但与庞大的市场规模不成正比的是NFT交易的治理路径与规则体系。目前,立法与理论依旧无法就如下两个问题达成共识,即NFT“是什么”以及“怎么管”。现阶段较为科学且现实的路径是承认NFT具备... 详细信息

NFT自其诞生伊始就受到了市场与资本的追捧,但与庞大的市场规模不成正比的是NFT交易的治理路径与规则体系。目前,立法与理论依旧无法就如下两个问题达成共识,即NFT“是什么”以及“怎么管”。现阶段较为科学且现实的路径是承认NFT具备多样化法律定性的可能,即同时具备数字财产、数字身份以及去中心化金融产品三类属性的可能,并且,在已有共识的基础上,构建最大化买卖双方权利转移的交易关系。具体到我国,考虑到本土化数字藏品与NFT之间的重叠关系,我们也应在着力发掘技术潜在价值的同时,探讨多样化NFT产品的开发,并在激活市场活力的同时进行交易规则与平台合规预研,以应对可能到来的金融、侵权等风险。

关键词：非同质化通证数字财产去中心化网络区块链

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