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Acta Oceanologica Sinica 2008年第3期27卷 161-171页

作者： yan yan zhao xinyi zhou liping College of Urban and Environmental Sciences Laboratory for Earth Surface Processes of Ministry of Education Peking University Beijing 100871 China

Aim to linking the variability of drought in northwest China to the oceanic influence of North Atlantic SSTs at the background of global warming and at the regional climate change shifting stages, year aridity index variations in northwest China and summer North Atlantic sea surface temperature （SST） variations are examined for the 44 a period of 1961-2004 using singular value decomposition （SVD） analysis. Results show that the SST anomalies （SSTA）in the North Atlantic in summer reflected three basic models. The first SVD mode of SST pattern shows a dipole - like variation with the positive center located at southwest and negative center at northeast of extratropical North Atlantic. And it strongly relates to the positive trend in AI variation in northwest China. The second coupled modes display the coherent positive anomalies in extratropical North Atlantic SST and the marked opposite trend of AI variability between north and south of Xinjiang. In addition, the lag correlation analysis of the first mode of SSTA and geopotential heights at 500 hPa variations also shows that the indication of the former influencing the latter configuration, which result in higher air temperature and less precipitation when the SSTA in the North Atlantic Ocean in summer motivated Eurasian circulation of EA pattern, further to influence the wet - dry variations in northwest China by the ocean-to - atmosphere forcing.

关键词： aridity index SSTA teleconnection patterns SVD

An efficient conversion model between acceleration and pseudo-acceleration response spectra considering effects of magnitude,distance,and site class

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 15-30页

作者： Liu Zheng zhao yan-Gang Zhang Haizhong Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China Faculty of Agriculture Yamagata University1-23Wakaba-machiTsuruoka-shiYamagata 997-8555Japan

Both acceleration and pseudo-acceleration response spectra play important roles in structural seismic ***,only one of them is generally provided in most seismic ***,many studies have attempted to develop conversion models between the acceleration response spectrum(SA)and the pseudo-acceleration response spectrum(PSA).Our previous studies found that the relationship between SA and PSA is affected by magnitude,distance,and site ***,we developed an SA/PSA model incorporating these ***,this model is suitable for cases with small and moderate magnitudes and its accuracy is not good enough for cases with large *** paper aims to develop an efficient SA/PSA model by considering influences of magnitude,distance,and site class,which can be applied to cases not only with small or moderate magnitudes but also with large *** this purpose,regression analyses were conducted using 16,660 horizontal seismic records with a wider range of *** magnitude of these seismic records varies from 4 to 9 and the distances vary from 10 to 200 *** ground motions were recorded at 338 stations covering four site *** comparing them with existing models,it was found that the proposed model shows better accuracy for cases with any magnitudes,distances,and site classes considered in this study.

关键词： acceleration response spectrum pseudo-acceleration response spectrum magnitude distance site class

Utilizing BP neural networks to accurately reconstruct the tritium depth profile in materials for BIXS

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Nuclear Science and Techniques 2025年第1期36卷 103-114页

作者： Chen zhao Wei Jin yan Shi Chang-An Chen Yi-Ying zhao Institute of Materials China Academy of Engineering PhysicsJiangyou 621908China

β-ray-induced X-ray spectroscopy(BIXS)is a promising method for tritium detection in solid materials because of its unique advantages,such as large detection depth,nondestructive testing capabilities,and low requirements for sample ***,high-accuracy reconstruction of the tritium depth profile remains a significant challenge for this *** this study,a novel reconstruction method based on a backpropagation(BP)neural network algorithm that demonstrates high accuracy,broad applicability,and robust noise resistance is *** average reconstruction error calculated using the BP network(8.0%)was much lower than that obtained using traditional numerical methods(26.5%).In addition,the BP method can accurately reconstruct BIX spectra of samples with an unknown range of tritium and exhibits wide applicability to spectra with various tritium ***,the BP network demonstrates superior accuracy and stability compared to numerical methods when reconstructing the spectra,with a relative uncertainty ranging from 0 to 10%.This study highlights the advantages of BP networks in accurately reconstructing the tritium depth profile from BIXS and promotes their further application in tritium detection.

关键词： β-ray-induced X-ray spectroscopy Tritium detection BP network Ridge regression Reconstruction problem

Modular assembly of Co4-thiacalix[4]arene units and Keggin-type SiW12O40 for visible-light photothermal conversion

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Tungsten 2025年第1期7卷 112-119页

作者： Jia-Hui Li Qing zhao Dong-Ao Mao Kun zhou Bao-Kuan Chen yan-Feng Bi School of Petrochemical Engineering Liaoning Petrochemical University

The construction of metal-organic coordination clusters（MCCs） using modular secondary building units is an important method for preparing functional *** this study,two new MCCs modularly assembled from Keggin-type {SiW12O40}H4TC4A=p-tert-Butylthiacalix[4]arene(SiW12) units and thiacalixarene-supported Co4-thiacalix[4]arene(Co4-TC4A polynuclear second-building units（PSBUs,H4TC4A=p-tert-Butylthiacalix[4]arene） are *** two MCCs,abbreviated as Co4-SiW12and Co8-SiW12,were structurally characterized by single-crystal X-ray *** Co4-SiW12is a supramolecular structure involving cation-anion interactions between Co4-TC4A PSBUs and ***8-SiW12features "barbell-like" shapes with two Co4-TC4A coordinatively linked to a Keggin-type SiW12unit on opposite via W-O_t-Co *** coordination of Co4-TC4A to SiW12in Co8-SiW12resulted in significantly improved photothermal conversion performances compared with Co4-SiW12and pure SiW12or ***-gap determination and photophysical analysis combined with density functional theory calculations indicated the binding mode between Co4-TC4A PSBUs and SiW12,which considerably influences the way of electron transport and the conversion ability of visible light to heat.

关键词： Modular construction Photothermal conversion Polyoxometalate Thiacalixarene

Establishing a new testing protocol of the electrochemical stability window for electric double-layer capacitors

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Science China Chemistry 2025年第1期68卷 217-225页

作者： Ruilin Hou Xiaoxi zhao Tingting Liang Qingyun Dou Shan Xu Xingbin yan School of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China Laboratory of Clean Energy Chemistry and Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Industrial Analysis and Testing Guangdong Academy of ScienceGuangzhou 510651China College of Engineering and Applied Sciences Nanjing UniversityNanjing 210093China

The electrochemical stability window(ESW)is crucial for determining the energy density of electric double-layer capacitors(EDLCs).However,current ESW testing protocols of EDLCs are strongly affected by artificial factors,thereby leading to unreliable *** solve this problem,we first identify the key shortcomings of the traditional protocols by analyzing their test ***,taking an aqueous carbon-based EDLC as an example,we design a side reaction descriptor to represent the response difference in the charging capacitance to side reactions between the cyclic voltammetry and galvanostatic chargedischarge *** the aid of this descriptor,we propose a new ESW testing protocol,which is not only able to completely avoid the adverse influence of subjective factors but also fully consider the operating condition *** protocol can be extended from the single electrode to the full *** work proposes a more rigorous definition of ESW and provides a reliable protocol for evaluating the ESW of EDLCs.

关键词： electric double-layer capacitors electrochemical stability window testing protocol side reaction descriptor operating limitation

Channel pruning on frequency response

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Science China(Information Sciences) 2025年第1期68卷 159-170页

作者： Hang LIN Yifan PENG Lin BIE Chenggang yan Xibin zhao Yue GAO School of Software Tsinghua University School of Automation Hangzhou Dianzi University

Network pruning has a significant role in reducing network parameters and accelerating the inference time of the network. Some existing methods prune the network based on the frequency of the data, and finally obtain a sub-network with high accuracy. However, according to our experimental analysis, different frequencies of information in the data contribute differently to the accuracy of the model, and using this information directly for pruning without making a selection will lead to incorrect results. We believe that pruning should retain the convolutional kernels in the network that process important information, while those kernels that process unimportant information should be removed. In this paper, we first investigate the meaning of each frequency band information in the spectrum and their contribution to the prediction accuracy of the network,and according to these results, we propose a new pruning method based on frequency response(PFR). Our PFR finds and removes the convolutional kernels in the network that specialize in processing unimportant information, resulting in a compact neural network model. PFR obtains significant experimental results on different datasets, for example, a 56.0% raduction of float points operations(FLOPs) on Res Net-50 and only 0.37% of Top-1 accuracy degradation on the Image Net dataset.

关键词： deep learning model compression filter pruning channel pruning frequency response

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Artificial intelligence advances drug delivery system and its clinical transition

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Science Bulletin 2025年第3期70卷 305-308页

作者： Hui Wang Xiao-yan You Guo-Ping zhao Master Lab for Innovative Application of Nature Products National Center of Technology Innovation for Synthetic BiologyTianjin Institute of Industrial BiotechnologyChinese Academy of Sciences(CAS)Tianjin 300308China Henan Engineering Research Center of Food Microbiology College of Food and BioengineeringHenan University of Science and TechnologyLuoyang 471023China Haihe Laboratory of Synthetic Biology Tianjin 300308China CAS-Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China CAS Key Laboratory of Quantitative Engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Since November 2022,ChatGPT,an artificial intelligence(AI)chatbot,has rapidly captured global attention for its detailed responses and articulated answers across a broad spectrum of knowledge domains[1],[2].All industries will reorient around it,prompting a reevaluation of how this technology could further promote scientifical research and its clinical applications.

关键词： system transition spectrum

Stress anisotropy regulated wrinkling pattern evolution on a core-shell soft cylinder

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 132-144页

作者： yan zhao Zhipan Jie Yilong Zhang Guo-yang Li yanping Cao Chao Jiang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China Institute of Biomechanics and Medical Engineering AMLDepartment of Engineering MechanicsTsinghua UniversityBeijing100084China

Diverse wrinkling patterns can occur on curved bilayer systems under differential growth or *** such systems,stress anisotropy is frequently encountered,and the coupling effect of curvature and stress anisotropy on the pattern evolution remains largely *** this study,we investigate the evolution of wrinkling patterns on a cylinder core-shell system with stress anisotropy leveraging both theoretical analysis and finite element *** buckling analysis has identified three distinct critical buckling modes regulated by the stress anisotropy,i.e.,axial sinusoidal mode,checkerboard mode,and circumferential sinusoidal *** finite element simulations,along with post-buckling analysis,reveal seven distinct evolutionary paths stemming from the three critical buckling *** present phase diagrams for both the critical buckling modes and their evolutionary paths,which are determined by dimensionless curvature and stress *** results not only expand the theoretical research on surface wrinkling of a core-shell soft cylinder but also introduce stress anisotropy as a significant parameter for regulating the wrinkling patterns and their evolutionary paths in curved bilayer *** revelation of a multitude of wrinkling patterns and their evolutionary pathways holds great potential for advancing applications that leverage tunable wrinkle surfaces.

关键词： wrinkling pattern evolutionary path stress anisotropy dimensionless curvature core-shell soft cylinder

Thermoelectric Modulation of Neat Ti_(3)C_(2)T_(x) MXenes by Finely Regulating the Stacking of Nanosheets

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Nano-Micro Letters 2025年第4期17卷 347-362页

作者： Junhui Tang Renyang Zhu Ya-Hsin Pai yan zhao Chen Xu Ziqi Liang Department of Materials Science Fudan UniversityShanghai 200433People’s Republic of China Spine Center Department of OrthopedicsShanghai Changzheng HospitalNaval Medical UniversityShanghai 200003People’s Republic of China

Emerging two-dimensional MXenes have been extensively studied in a wide range of fields thanks to their superior electrical and hydrophilic attributes as well as excellent chemical stability and mechanical *** them,the ultrahigh electrical conductivity(σ)and tunable band structures of benchmark Ti_(3)C_(2)T_(x) MXene demonstrate its good potential as thermoelectric(TE)***,both the large variation ofσreported in the literature and the intrinsically low Seebeck coefficient(S)hinder the practical ***,this study has for the first time systematically investigated the TE properties of neat Ti_(3)C_(2)T_(x) films,which are finely modulated by exploiting different dispersing solvents,controlling nanosheet sizes and constructing ***,deionized water is found to be superior for obtaining closely packed MXene sheets relative to other polar ***,a simultaneous increase in both S andσis realized via elevating centrifugal speed on MXene aqueous suspensions to obtain small-sized nanosheets,thus yielding an ultrahigh power factor up to~156μW m^(-1) K^(-2).Third,S is significantly enhanced yet accompanied by a reduction inσwhen constructing MXene-based nanocomposites,the latter of which is originated from the damage to the intimate stackings of MXene ***,a correlation between the TE properties of neat Ti_(3)C_(2)T_(x) films and the stacking of nanosheets is elucidated,which would stimulate further exploration of MXene TEs.

关键词： MXene Nanosheet stacking Electrical conductivity Seebeck coefficient Thermoelectrics

Numerical simulation of microstructure and microporosity morphology in directional solidification of aluminum-copper alloys:Effect of copper content and withdrawal rate

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China Foundry 2025年第1期22卷 33-44页

作者： Wei Yuan Hai-dong zhao Xu Shen Chun Zou Yuan Liu Qing-yan Xu National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Tsinghua UniversityBeijing 100084China

Microporosity formed in the solidification process of Al alloys is detrimental to the alloy properties.A two-dimensional cellular automaton(CA)model was developed to simulate the microstructure and microporosity formation in Al-Cu alloys,considering variations in Cu content and solidification *** results indicate that the Cu content primarily influences the growth of *** validate the model,directional solidification experiments were conducted on Al-Cu alloys with varing Cu contents and withdrawal *** experimental results of dendrites and microporosity characteristics agree well with the predictions from the developed model,thus confirming the validity of the *** alloy’s liquidus temperature,dendrite morphology,and hydrogen saturation solubility arising from different Cu contents have significant effects on microporosity *** withdrawal rate primarily affects the nucleation of hydrogen microporosity by altering cooling rates and dendritic growth rates,resulting in different microporosity characteristics.

关键词： microporosity dendrites cellular automaton Al-Cu alloys directional solidification