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Nuclear Science and Techniques 2024年第5期35卷 173-185页

作者： He-lin Gong Han Li Dunhui Xiao Sibo cheng Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences Tongji UniversityShanghai 200092China Department of Computing Data Science InstituteImperial College LondonLondon SW72AZUK

The aging of operational reactors leads to increased mechanical vibrations in the reactor *** vibration of the incore sensors near their nominal locations is a new problem for neutronic field *** field-reconstruction methods fail to handle spatially moving *** this study,we propose a Voronoi tessellation technique in combination with convolutional neural networks to handle this *** from movable in-core sensors were projected onto the same global field structure using Voronoi tessellation,holding the magnitude and location information of the *** convolutional neural networks were used to learn maps from observations to the global *** proposed method reconstructed multi-physics fields(including fast flux,thermal flux,and power rate)using observations from a single field(such as thermal flux).Numerical tests based on the IAEA benchmark demonstrated the potential of the proposed method in practical engineering applications,particularly within an amplitude of 5 cm around the nominal locations,which led to average relative errors below 5% and 10% in the L_(2) and L_(∞)norms,respectively.

关键词： Voronoi tessellation Field reconstruction Nuclear reactors Reactor physics On-line monitoring

Persistent radical anion of perylene dianhydride:an emerging metal-free photocatalyst for near-infrared photocontrolled RAFT polymerization

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Science China Chemistry 2024年第2期67卷 677-686页

作者： Haitao Zhao Guoqing Bian xiang Xu Weiwei He Lifen Zhang Zhenping cheng State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSuzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China

Developing a new type of photocatalyst(PC) and catalytic mechanism for near-infrared(NIR) photocontrolled reversibledeactivation radical polymerization(RDRP) system is charming but ***,a novel PC of the persistent radical anion(PRA)(possessing the properties of both radical and anion) was developed for NIR photocontrolled reversible additionfragmentation chain transfer(RAFT) polymerization,enabling successful polymerization while gaining a deep insight into the mechanism of photo-induced electron transfer RAFT(PET-RAFT) *** from the conventional and wellaccepted reductive quenching(RQ) pathway,in which the radical anion intermediates of PCs(PCs^(·-)) must be generated in an excited state(ES),here,the PRA(3,4,9,10-perylenetetracarboxylic dianhydride radical anion(PTCDA^(·-))) could generate conveniently in situ in the ground state(GS) and subsequently serve as highly efficient PC in the NIR region(740–850 nm).The successful implementation of this strategy elucidates the peculiar role played by light and the real way of electron transfer *** fact,the transfer of a single electron from PRA to chain transfer agent(CTA) and cleavage of the C–S bonds is a process from ES to GS,rather than always from GS(PCs^(·-)) to GS(CTA) in the RQ pathway as is well known to *** addition,the excellent spatial-temporal control and powerful penetration ability of the NIR light were also confirmed by this PRAcatalyzed polymerization system.

关键词： photocatalyst persistent radical anion(PRA) near-infrared(NIR)light reversible-deactivation radical polymerization(RDRP) photo-induced electron transfer RAFT(PET-RAFT)polymerization

Mitigating set-stuck failure in 3D phase change memory: substituting square pulses with surge pulses

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Science China(Information Sciences) 2024年第5期67卷 295-301页

作者： Ninghua LI Wang CAI Jun xiang Hao TONG Weiming cheng xiangshui MIAO School of Integrated Circuits Huazhong University of Science and Technology Hubei Yangtze Memory Laboratories Hubei Institute of Measurement and Testing Technology

In the devices that integrate phase change memory(PCM) and ovonic threshold switching(OTS),the OTS threshold voltage often surpasses the RESET operation voltage of PCM. The conventional application of square pulses hinders the successful completion of the SET operation in these integrated devices. To address this challenge, a novel pulse called the surge pulse is introduced, which comprises a high amplitude pulse for OTS activation and a low amplitude pulse for PCM operation. By employing COMSOL simulation,the operational effectiveness of both square pulses and surge pulses is validated. Test results reveal that using a square pulse to operate the integrated device accelerates the occurrence of SET-stuck failure(SSF).In contrast, the surge pulse enables the integrated device to operate for at least 1000 cycles while preserving the essential cyclic characteristics. Additionally, an investigation into the overshoot component of the surge pulse is conducted, revealing that an increase in overshoot amplitude and pulse width also accelerates the emergence of SSF. By applying the theory of ion migration induced by the electric field, the root cause of SSF in integrated devices is explained, and the accuracy of the theory is validated through the application of a reverse pulse. In summary, this study elucidates the rationality of replacing the square pulse with a surge pulse, presenting a superior approach for operating PCM and OTS integrated devices.

关键词： surge pulse phase change memory (PCM) integration SET-stuck failure (SSF) square pulse

模拟月壤颗粒形状特征及其对抗剪强度影响分析

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东北大学学报（自然科学版） 2016年第11期37卷 1640-1644页

作者：林呈祥钟世英凌道盛浙江大学软弱土与环境土工教育部重点实验室浙江杭州310058

为研究颗粒形状特征对抗剪强度的影响,对模拟月壤颗粒进行体视显微镜扫描拍照,并利用图形处理软件对各粒径组颗粒的形状特征进行量化统计.结果表明:模拟月壤颗粒的主要形状有圆形、类椭圆形、类三角形和类正方形等.利用PFC 3D软件中的"C... 详细信息

为研究颗粒形状特征对抗剪强度的影响,对模拟月壤颗粒进行体视显微镜扫描拍照,并利用图形处理软件对各粒径组颗粒的形状特征进行量化统计.结果表明:模拟月壤颗粒的主要形状有圆形、类椭圆形、类三角形和类正方形等.利用PFC 3D软件中的"Clump"命令构造出不同形状的模拟月壤颗粒并通过三轴试验数值模型研究其抗剪强度指标值,模拟结果表明:颗粒形状对模拟月壤的抗剪强度指标值有着明显的影响,其中构造出的类椭圆体颗粒试样抗剪强度最大,而规则的球体颗粒试样的抗剪强度最小;当颗粒形状都是类三角体时,凹凸度越大,试样的抗剪强度指标值也越大.

关键词：模拟月壤颗粒形状三轴压缩试验抗剪强度 PFC3D数值模拟

Microstructure recognition of steels by machine learning based on visual attention mechanism

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Journal of Iron and Steel Research International 2024年第4期31卷 909-923页

作者： Xing-yu Chen lin cheng cheng-yang Hu Yu-peng Zhang Kai-ming Wu The State Key Laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science on Metallurgical ProcessingInternational Research Institute for Steel TechnologyCollaborative Center on Advanced SteelsWuhan University of Science and TechnologyWuhan 430081HubeiChina Metals Valley and Band(Foshan)Metallic Composite Materials Co. Ltd.Foshan 528000GuangdongChina

U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentation as well as recent microstructure image segregation of the *** representative visual attention mechanism modules,named as squeeze-and-excitation networks,convolutional block attention module,and extended calibration algorithm,were intro-duced into the traditional U-Net architecture to further improve the prediction *** is found that compared with the original U-Net architecture,the evaluation index of the improved U-Net architecture has been significantly improved for the microstructure segmentation of the steels with the ferrite/martensite composite microstructure and pearlite/ferrite composite microstructure and the complex martensite/austenite island/bainite microstructure,which demonstrates the advantages of the utilization of the visual attention mechanism in the microstructure *** reasons for the accuracy improvement were discussed based on the feature maps analysis.

关键词： Microstructure recognition-Steel Machine learning Visual attention mechanism Visualization

Skin-inspired interface modification strategy toward a structurefunction integrated hybrid smart fabric system with self-powered sensing property for versatile applications

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Nano Research 2024年第9期17卷 8200-8208页

作者： xiang cheng Teng Chen De Gong Pengcheng Ma Bo Chen Jun Cai Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100190China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beijing U-Precision Tech Co. Ltd.Beijing 100176China University of Chinese Academy of Sciences Beijing 100049China

Fabric-based composites with superior mechanical properties and excellent perceptive function are highly ***,it remains a huge challenge to attain structure-function integration,especially for hybrid fabric ***,a skin-inspired interface modification strategy is proposed toward this target by constructing a hybrid smart fabric system consisting of two types of smart fabrics:carbon nanotube(CNT)/MXene-modified aramid fabrics and zinc oxide nanorod(ZnO NR)-modified carbon *** on that,flexible piezoelectric pressure sensors with skin-like hierarchical perception interfaces are fabricated,which demonstrate superb sensitivity of 2.39 V·kPa^(-1)and are capable of various wearable monitoring ***,the interface-modified hybrid fabric reinforced plastics can also be fabricated,which are proven to possess 13.6%higher tensile strength,10.1%elastic *** impressively,their average energy absorption can be improved by 111.9%,accompanied with inherent damage alert *** offers a paradigm to fabricate structure-function integrated hybrid smart fabric composites for the smart clothing and intelligent aerial vehicles.

关键词： hybrid fabrics interface modification piezoelectric pressure sensors self-diagnostic composites structure-function integration

The innovative safe herbicide dienediamine saves paraquat

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Molecular Plant 2024年第1期17卷 11-12页

作者： Jin-Qiu Xia Ping Xu cheng-Bin xiang Division of Life Sciences and Medicine Division of Molecular&Cell BiophysicsHefei National Science Center for Physical Sciences at the MicroscaleMOE Key Laboratory for Membraneless Organelles and Cellular DynamicsUniversity of Science and Technology of ChinaThe Innovation Academy of Seed DesignChinese Academy of SciencesHefeiAnhui Province 230027China Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterCAS Center for Excellence in Molecular Plant SciencesShanghai 201602China

Throughout the history of agriculture,the challenge of weed management has endured,necessitating significant investments to facilitate ideal crop growth and maximize *** for weed control mainly involve manual and chem... 详细信息

关键词： approach. manual chemical

Convergence analysis for complementary-label learning with kernel ridge regression

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 533-544页

作者： NIE Wei-lin WANG cheng XIE Zhong-hua School of Mathematics and Statistics Huizhou UniversityHuizhou 516007China School of Computer Science and Engineering Huizhou UniversityHuizhou 516007China

Complementary-label learning(CLL)aims at finding a classifier via samples with complementary *** data is considered to contain less information than ordinary-label *** transition matrix between the true label and the complementary label,and some loss functions have been developed to handle this *** this paper,we show that CLL can be transformed into ordinary classification under some mild conditions,which indicates that the complementary labels can supply enough information in most *** an example,an extensive misclassification error analysis was performed for the Kernel Ridge Regression(KRR)method applied to multiple complementary-label learning(MCLL),which demonstrates its superior performance compared to existing approaches.

关键词： multiple complementary-label learning partial label learning error analysis reproducing kernel Hilbert spaces

Recent progress of in situ/operando characterization techniques for electrocatalytic energy conversion reaction

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Chinese Chemical Letters 2024年第9期35卷 92-101页

作者： Zhao Li Huimin Yang Wenjing cheng lin Tian School of Materials and Chemical Engineering Xuzhou University of TechnologyXuzhou 221018China University and College Key Lab of Natural Product Chemistry and Application in Xinjiang School of Chemistry and Environmental ScienceYili Normal UniversityYining 835000China

Catalysts can significantly promote the reaction dynamics and are therefore considered crucial components for achieving high electrochemical energy conversion ***,the active sites of the catalysts,particularly for nano-level and atomic-level catalysts commonly undergo reconstruction under practical ***,obtaining an in-depth and systematic understanding on the real active sites through in situ/operando characterization techniques is a prerequisite for establishing the structureperformance relationship and guiding the future design of more efficient ***,we summarize the recent progress of in situ/operando characterization techniques for identifying the nature of active sites of electrocatalysts when used in electrocatalytic energy conversion ***,our focus lies in the fundamental principles of various in situ/operando characterization techniques,with particular emphasis on their applications for electrocatalytic *** that,the challenges and perspective insights are also added in the final section to highlight the future direction of this important field.

关键词： In situ techniques Electrocatalysis Active sites Energy conversion

Sexual Dimorphism and Female Reproductive Characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China

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Asian Herpetological Research 2024年第1期15卷 49-58页

作者： Yu DU Xiaming ZHU Chixian lin Yuntao YAO xiang JI Hainan Key Laboratory for Herpetological Research College of Fisheries and Life SciencesHainan Tropical Ocean UniversitySanya 572022HainanChina Zhejiang Provincial Key Laboratory for Water Environment and Marine Biological Resources Protection College of Life and Environmental SciencesWenzhou UniversityWenzhou 325035ZhejiangChina Institute for Eco-environmental Research of Sanyang Wetland Wenzhou UniversityWenzhou 325014ZhejiangChina

We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South *** our sample the largest female and male were 61.1 and 55.2 mm snout-vent length(SVL),*** mean SVL was larger in adult females(52.0 mm)than in adult males(48.3 mm).Juveniles were sexually dimorphic in head length but not in other examined morphological *** males were longer in head length and shorter in abdomen length and fore-limb length than adult females of the same *** shifts in sexual dimorphism in body shape were evident,as revealed by the fact that morphological differences between the sexes were more pronounced in adults than in *** produced a single litter of 3–6 offspring per season from early August to early *** size,litter mass and offspring(neonate)mass were positively related to female *** mass was independent of relative *** the above findings we draw three main ***,females are the larger sex in ***,and sexual dimorphism in body shape is more pronounced in adults than in ***,larger female *** produce more and larger offspring and thus heavier litters than smaller ***,the offspring size-number trade-off does is not evident in ***.

关键词： fecundity morphology offspring size-number trade-off reproduction scincidae sexual dimorphism