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Journal of Energy Chemistry 2024年第6期93卷 16-23,I0002页

作者： Yihong Tong Ruicheng cao Guanghui Xu Yifeng Xia Hongyuan Xu Hong Jin Hui Xu Xi’an Jiaotong University Suzhou Academy Suzhou 215123JiangsuChina Nano Science and Technology Institute University of Science and Technology of ChinaSuzhou 215123JiangsuChina

Free-standing silicon anodes with high proportion of active materials have aroused great attention;however,the mechanical stability and electrochemical performance are severely ***,to resolve the appeal issues,a free-standing anode with a"corrugated paper"shape on micro-scale and a topological crosslinking network on the submicron and nano-scale is ***,an integrated three-dimensional electrode structure is constructed based on robust carbon nanotubes network with firmly anchored SiNPs via forming interlocking *** which,the hierarchical interlocking structure is achieved by directional induction of the binder,which ensures well integration during cycling so that significantly enhances mechanical stability as well as electronic and ionic conductivity of *** from it,this anode exhibits outsta nding performance under harsh service conditions including high Si loading,ultrahigh areal capacity(33.2 mA h cm^(-2)),and high/low temperatures(-15-60℃),which significantly extends its practical ***,the optimization mechanism of this electrode is explored to verify the crack-healing and structure-integration maintaining along cycling via a unique self-stabilization ***,from both the fundamental and engineering views,this strategy offers a promising path to produce high-performance free-standing electrodes for flexible device applications especially facing volume effect challenges.

关键词： Topological network Self-stabilization Flexibility Free-standing Silicon anode

Refined acoustic holography via nonlocal metasurfaces

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 113-123页

作者： Shuhuan Xie Hongyu Ma Junmei cao Fangshuo Mo Qian Cheng Yong Li Tong Hao Institute of Acoustics School of Physics Science and EngineeringTongji UniversityShanghai 200092China Center for Spatial Information Science and Sustainable development Applications Tongji UniversityShanghai 200092China College of Surveying and Geo-Informatics Tongji UniversityShanghai 200092China

Holography can provide the desired wavefront phase and/or amplitude for imaging,particle manipulation,bacteria trapping,and cell patterning in optics and ***,previous work on acoustic holography is mostly based on local design optimization,either using active control of the sound source or relying on the structural design to provide the desired *** precise control over the acoustic field remains a significant ***,we realize refined single-plane symmetric binary amplitude,asymmetric intensity gradient amplitude,and bi-objective hologram through the non-local holographic imaging theory that considers the acoustic coupling of structural units in *** taking into account the self-radiation and mutual radiation between many small units on a plate of well-designed thickness,as well as the transmission through the plate's apertures,we can effectively regulate the sound field behind the *** demonstrate the effectiveness of our approach through numerical simulations and experiments,showcasing a circle,a black hole,and a bi-objective with a circle and a square ***,the acoustic black hole hologram precisely reconstructs the intensity gradient distribution at two bright *** non-local holographic imaging theory is valuable for the fine-intensity regulation of the sound field and is expected to be applied in ultrasound diagnosis and treatment,medical imaging,and other fields.

关键词： acoustic holograms non-local interactions fine intensity modulation acoustic metasurfaces

Improved forecasting via physics-guided machine learning as exemplified using“21·7”extreme rainfall event in Henan

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Science China Earth Sciences 2024年第5期67卷 1652-1674页

作者： Qi ZHONG Zhicha ZHANG Xiuping YAO Shaoyu HOU Shenming FU Yong cao Linguo JING China Meteorological Administration Training Center Beijing 100081China State Key Laboratory of Severe weather Chinese Academy of Meteorological SciencesBeijing 100081China Zhejiang Meteorological Observatory Hangzhou 310017China Hebei Provincial weather Modification Center Shijiazhuang 050020China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China National Meteorological Center Beijing 100081China School of Computer Science Chengdu University of Information TechnologyChengdu 610225China

As a natural disaster,extreme precipitation is among the most destructive and influential,but predicting its occurrence and evolution accurately is very challenging because of its rarity and *** the example of the“21·7”extreme precipitation event(17–21 July 2021)in Henan Province,this study explores the potential of using physics-guided machine learning to improve the accuracy of forecasting the intensity and location of extreme *** physics-guided ways of embedding physical features,fusing physical model forecasts and revised loss function are used,i.e.,(1)analyzing the anomalous circulation and thermodynamical factors,(2)analyzing the multi-model forecast bias and the associated underlying reasons for it,and(3)using professional forecasting knowledge to design the loss function,and the corresponding results are used as input for machine learning to improve the forecasting *** results indicate that by learning the relationship between anomalous physical features and heavy precipitation,the forecasting of precipitation intensity is improved significantly,but the location is rarely adjusted and more false alarms *** reasons for this are as *** anomalous features used here mainly contain information about large-scale systems and factors which are consistent with the model precipitation deviation;moreover,the samples of extreme precipitation are sparse and so the algorithm used here is ***,by combining“good and different”multi models with machine learning,the advantages of each model are extracted and then the location of the precipitation center in the forecast is improved ***,by combining the appropriate anomalous features with multi-model fusion,an integrated improvement of the forecast of the rainfall intensity and location is ***,this study is a novel exploration to improve the refined forecasting of heavy precipitation with extreme intensity and high variability,

关键词： Extreme precipitation event Refined assessment Anomalous physical features Multi-model fusion Machine learning

The pseudospectrum and spectrum (in)stability of quantum corrected Schwarzschild black hole

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 59-79页

作者： Li-Ming cao Jia-Ning Chen Liang-Bi wu Libo Xie Yu-Sen Zhou Peng Huanwu Center for Fundamental Theory Interdisciplinary Center for Theoretical Study and department of Modern Physics University of Science and Technology of China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCAS

In this study, we investigate the pseudospectrum and spectrum(in)stability of quantum corrected Schwarzschild black ***, we use the hyperboloidal framework to cast the quasinormal mode(QNM) problem into an eigenvalue problem associated with a non-selfadjoint operator, and then the spectrum and pseudospectrum are depicted. Besides, the invariant subspace method is exploited to improve the computational efficiency for pseudospectrum. The investigation into the spectrum(in)stability entails two main aspects. On the one hand, we calculate the spectra of the quantum corrected black hole, then by the means of the migration ratio, the impact of the quantum correction effect on the Schwarzschild black hole has been *** results indicate that the so-called “migration ratio instability” will occur for small black holes with small angular momentum number l. In the eikonal limit, the migration ratios remain the same for each overtone. On the other hand, we study the spectrum(in)stability of the quantum corrected black hole by directly adding some particular perturbations into the effective potential,where perturbations are located at the event horizon and null infinity, respectively. There are two interesting observations under the same perturbation energy norm. First, perturbations at infinity are more capable of generating spectrum instability than those at the event horizon. Second, we find that the peak distribution can lead to the instability of QNM spectrum more efficiently than the average distribution.

关键词： quasinormal modes pseudospectrum hyperboloidal coordinate

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Efficient overall photosynthesis of H_(2)O_(2) by the BTz@Mn_(0.2)Cd_(0.8)S S-scheme heterojunction

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Science China Chemistry 2024年第6期67卷 1953-1960页

作者： Zhongyue Chen Sijie wan Bei Cheng wang wang Yao Xiang Jiaguo Yu Shaowen cao State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China Hubei Technology Innovation Center for Advanced Composites Wuhan University of TechnologyWuhan430070China Hospital of wuhan University of Technology Wuhan University of TechnologyWuhan430070China Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan430074China

The photosynthesis of hydrogen peroxide(H_(2)O_(2))through the selective 2e^(-)oxygen reduction reaction(ORR)from O_(2)and H_(2)O stands out as an environmentally sustainable and cost-effective method for generating this essential ***,the widespread application of most photocatalysts is impeded by their reliance on sacrificial *** this context,we present a noteworthy advancement in the form of a step-scheme(S-scheme)heterojunction involving a donor-acceptor(d-A)-conjugated polymer and manganese cadmium sulfide(BTz@MCS).This innovative configuration enables efficient photocatalytic H_(2)O_(2)production within a non-sacrificial system,showcasing an impressive H_(2)O_(2)yield of 5,368μmol g^(-1)h^(-1)and an apparent quantum yield of 4.5%at 420 *** insights gained from in-situ irradiated X-ray photoelectron spectroscopy(ISIXPS),in-situ diffuse reflectance infrared Fourier transformations spectroscopy(dRIFTS),and density function calculations(dFT),it is revealed that the sp^(2)C between thiazole-thiazole rings at the BTz and the concentrated holes at the MCS function as spatially separated redox *** centers catalyze the selective 2e^(-)ORR and 4e^(-)water oxidation reaction(wOR)*** O_(2)generated from the wOR is subsequently utilized by the ORR cycle,enabling the overall photosynthesis of H_(2)O_(2)with accelerated total reaction ***,the high photocatalytic performance of the developed catalyst is attributed to well-designed S-scheme heterojunctions with tuned band *** spatially separated redox centers and effective transfer of photogenerated charge carriers facilitated by the internal electric field significantly enhance reaction *** study introduces a promising avenue for photocatalytic H_(2)O_(2)production without sacrificial agents,providing valuable insights into the underlying mechanisms in S-scheme heterojunctions.

关键词： hydrogen peroxide non-sacrificial redox centers S-scheme heterojunction