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national Science Review 2024年第4期11卷 130-140页

作者： Huimin Wang Zhe-ning Chen Yuanyuan Wang Dongshuang Wu Minna cao Fanfei Sun Rong cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences School of Materials Science and Engineering Nanyang Technological University Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied Physics Chinese Academy of Sciences Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China

The absence of efficient and durable catalysts for oxygen evolution reaction（OER） is the main obstacle to hydrogen production through water splitting in an acidic ele ctrolyte.Here,we report a controllable synthesis method of surface IrOxwith changing Au/Ir compositions by constructing a range of sub-10-nm-sized core-shell nanocatalysts composed of an Au core and AuxIr1-xalloy shell.In particular,Au@Au0.43Ir0.57exhibits 4.5 times higher intrinsic OER activity than that of the commercial Ir/C.Synchrotron X-ray-based spectroscopies,electron microscopy and density functional theory calculations revealed a balanced binding of reaction intermediates with enhanced activity.The water-splitting cell using a load of 0.02 mgIr/cm2of Au@Au0.43Ir0.57as both anode and cathode can reach 10 mA/cm2at 1.52 V and maintain activity for at least194 h,which is better than the cell using the commercial couple Ir/C‖Pt/C（1.63 V,0.2 h）.

关键词： controllable synthesis of surface IrOx oxygen evolution reaction acidic water splitting catalytic stability transition metal catalysts

Materials and structural design for preferable Zn deposition behavior toward stable Zn anodes

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SmartMat 2024年第1期5卷 1-37页

作者： Qinghe cao Yong Gao Jie Pu Abdelnaby M.Elshahawy cao Guan Key Laboratory of Flexible Electronics of Zhejiang Province Ningbo Institute of Northwestern Polytechnical UniversityNingboChina Institute of Flexible Electronics Northwestern Polytechnical UniversityXi'anChina Department of Physics Faculty of ScienceAssiut UniversityAssiutEgypt

Benefiting from the high capacity of Zn metal anodes and intrinsic safety of aqueous electrolytes,rechargeable Zn ion batteries(ZIBs)show promising application in the post‐lithium‐ion period,exhibiting good safety,low cost,and high energy density.However,its commercialization still faces problems with low Coulombic efficiency and unsatisfied cycling performance due to the poor Zn/Zn2+reversibility that occurred on the Zn anode.To improve the stability of the Zn anode,optimizing the Zn deposition behavior is an efficient way,which can enhance the subsequent striping efficiency and limit the dendrite growth.The Zn deposition is a controlled kinetics‐diffusion joint process that is affected by various factors,such as the interaction between Zn2+ions and Zn anodes,ion concentration gradient,and current distribution.In this review,from an electrochemical perspective,we first overview the factors affecting the Zn deposition behavior and summarize the modification principles.Subsequently,strategies proposed for interfacial modification and 3D structural design as well as the corresponding mechanisms are summarized.Finally,the existing challenges,perspectives on further development direction,and outlook for practical applications of ZIBs are proposed.

关键词： 3D structuraldesign interfacialmodification long‐term stability Znanode Zndeposition behavior

Fatigue-resistant Hydrogels

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Chemical Research in Chinese Universities 2024年第1期40卷 64-77页

作者： LI Luofei LEI Hai cao Yi Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructureDepartment of PhysicsNanjing UniversityNanjing 210093P.R.China Department of Physics Zhejiang UniversityHangzhou 310027P.R.China

Hydrogels have been extensively studied for applications in various fields, such as tissue engineering and soft robotics, as determined by their mechanical properties. The mechanical design of hydrogels typically focuses on the modulus, toughness, and deformability. These characteristics play important roles and make great achievements for hydrogel use. In recent years, a growing body of research has concentrated on the fatigue property of hydrogels, which determines their resistance to crack propagation in the networks during cyclic mechanical loads for applications. However, knowledge of hydrogel fatigue behavior remains notably deficient. Here, we present a brief overview of the fatigue behavior of hydrogels, encompassing the general experimental methods to measure the fatigue property and fundamental theoretical calculation models. Then, we highlight multiple strategies to enhance the fatigue resistance of hydrogels. Finally, we present our perspectives on fatigue-resistant hydrogels, outstanding challenges and potential directions for future research.

关键词： Hydrogel Fatigue-resistant Fracture

Accuracy of numerical relativity waveforms with respect to space-based gravitational wave detectors

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Communications in Theoretical Physics 2024年第1期76卷 82-95页

作者： Zun Wang Junjie Zhao Zhoujian cao Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China

As with the laser interferometer gravitational-wave observatory(LIGO),the matched filtering technique will be critical to the data analysis of gravitational wave detection by space-based detectors,including LISA,Taiji and Tianqin.Waveform templates are the basis for such matched filtering techniques.To construct ready-to-use waveform templates,numerical relativity waveforms are a starting point.Therefore,the accuracy issue of numerical relativity waveforms is critically important.There are many investigations regarding this issue with respect to LIGO.But unfortunately there are few results on this issue with respect to space-based detectors.The current paper investigates this problem.Our results indicate that the existing numerical relativity waveforms are as accurate as 99%with respect to space-based detectors,including LISA,Taiji and Tianqin.Such an accuracy level is comparable to that with respect to LIGO.

关键词： numerical relativity gravitational wave binary black hole

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Grassland-type ecosystem stability in China differs under the influence of drought and wet events

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Journal of Arid Land 2024年第5期16卷 615-631页

作者： cao Wenyu BAI Jianjun YU Leshan School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China International Business School Shaanxi Normal UniversityXi'an 710119China

Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a major threat to global ecological stability. Variations in stability among different ecosystemshave been confirmed, but it remains unclear whether there are differences in stability within the sameterrestrial vegetation ecosystem under the influence of climate events in different directions and intensities.China's grassland ecosystem includes most grassland types and is a good choice for studying this issue.This study used the Standardized Precipitation Evapotranspiration Index-12 (SPEI-12) to identify thedirections and intensities of different types of climate events, and based on Normalized DifferenceVegetation Index (NDVI), calculated the resistance and resilience of different grassland types for 30consecutive years from 1990 to 2019 (resistance and resilience are important indicators to measurestability). Based on a traditional regression model, standardized methods were integrated to analyze theimpacts of the intensity and duration of drought and wet events on vegetation stability. The resultsshowed that meadow steppe exhibited the highest stability, while alpine steppe and desert steppe had thelowest overall stability. The stability of typical steppe, alpine meadow, temperate meadow was at anintermediate level. Regarding the impact of the duration and intensity of climate events on vegetationecosystem stability for the same grassland type, the resilience of desert steppe during drought was mainlyaffected by the duration. In contrast, the impact of intensity was not significant. However, alpine steppewas mainly affected by intensity in wet environments, and duration had no significant impact. Ourconclusions can provide decision support for the future grassland ecosystem governance.

关键词： grassland ecosystem stability resistance resilience different climate types drought climate event wet climate event

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Correlation between TGFβ1 Gene Polymorphism and Asthma in Baise, Guangxi Children

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Journal of Biosciences and Medicines 2024年第5期12卷 300-311页

作者： Fangxin cao na Lin Juntao Lin Gai Yang Xintong Wang Graduate School of Youjiang Medical University for nationalities Baise China Department of Pediatric Affiliated Hospital of Youjiang Medical University for Nationalities Baise China

Objective: This research was to study the correlation between the rs1800469, rs1800470, rs2241712, rs224171 and rs4803455 of TGFβ1 gene and asthma in Baise, Guangxi children. This research also studied the relationship between serum concentration of TGFβ1 and childhood asthma. Method: From June 2022 to December 2023, 121 children had physical examination in affiliated Hospital of Youjiang Medical University for nationalities were selected as control group and 118 children suffered from asthma in affiliated Hospital of Youjiang Medical University for nationalities during the same period were selected as asthma group. Result: There was no correlation between rs1800469, rs1800470, rs2241712, rs2241715, rs4803455 and asthma in Baise, Guangxi children. Linkage disequilibrium analysis showed that there were strong linkage disequilibrium among rs1800469, rs1800470, rs2241712, rs2241715 and rs4803455. Their haplotypes had no significant correlation with childhood asthma. The serum concentration of TGFβ1 in asthma group was lower than that in control group (p β1 had no significant relationship with the genotypes of rs1800469, rs1800470, rs2241712, rs2241715 and rs4803455.

关键词： TGFβ1 Chilhood Asthma SNP

运行参数变化时双馈风电机组振荡机理及特性研究

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太阳能学报 2024年第3期45卷 54-64页

作者：曹娜苏亚妮于群山东科技大学电气与自动化工程学院青岛266590

为研究风力机功率在风电机组中传播、变换时与风电机组各环节的耦合关系及机组输出功率振荡特性,以双馈风电机组为例,首先计及塔影效应和风剪切、风速大小,推导各子系统的能量函数;考虑机组阻尼及风速变化,分析各子系统能量变化及机组... 详细信息

为研究风力机功率在风电机组中传播、变换时与风电机组各环节的耦合关系及机组输出功率振荡特性,以双馈风电机组为例,首先计及塔影效应和风剪切、风速大小,推导各子系统的能量函数;考虑机组阻尼及风速变化,分析各子系统能量变化及机组输出功率的振荡特性;最后,在PSCAD/EMTDC上建模仿真,通过能量变化深入分析风力机功率在机组内传播机理及功率振荡特性。仿真结果表明:含低频振荡分量的风力机功率通过负阻尼双馈风电机组时,与机组的次同步振荡耦合,风力机子系统、发电机及励磁子系统输出能量大幅增加,机组输出功率中既有低频振荡也有次同步振荡,它们随机组阻尼和风速变化而变化;风速变化时双馈风电机组消耗的能量主要由风力机子系统决定。

关键词：双馈风电机组次同步振荡低频振荡塔影效应和风剪切耦合变流器控制参数

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The Life Cycle of Knowledge in Big Language Models:A Survey

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Machine Intelligence Research 2024年第2期21卷 217-238页

作者： Boxi cao Hongyu Lin Xianpei Han Le Sun Chinese Information Processing Laboratory Beijing 100190China State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 101408China

Knowledge plays a critical role in artificial intelligence.Recently,the extensive success of pre-trained language models(PLMs)has raised significant attention about how knowledge can be acquired,maintained,updated and used by language models.Despite the enormous amount of related studies,there is still a lack of a unified view of how knowledge circulates within language models throughout the learning,tuning,and application processes,which may prevent us from further understanding the connections between current progress or realizing existing limitations.In this survey,we revisit PLMs as knowledge-based systems by dividing the life circle of knowledge in PLMs into five critical periods,and investigating how knowledge circulates when it is built,maintained and used.To this end,we systematically review existing studies of each period of the knowledge life cycle,summarize the main challenges and current limitations,and discuss future directions.

关键词： Pre-trained language model knowledge acquisition knowledge representation knowledge probing knowledge editing knowledge application

Experimental Study of Temperature Control Based on Composite Phase Change Materials during Charging and Discharging of Battery

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Journal of Thermal Science 2024年第2期33卷 578-590页

作者： LI Xiaolin WANG Jun cao Wenxiang ZHANG Xuesong School of Automotive and Traffic Engineering Jiangsu UniversityZhenjiang212013China

This study is to utilize the heat-absorbing and releasing capabilities of phase change materials(PCM)to regulate the surface temperature fluctuations of batteries during charging and discharging.The goal is to keep the battery within the optimal operating temperature range.The impact of PCM thickness and phase change temperature on battery temperature is investigated by encircling a cylindrical battery with a PCM ring.To improve the thermal conductivity of PCM,expanded graphite(EG) is added to make a composite phase change material(CPCM),and the effects of various EG mass ratios on battery surface temperature and CPCM utilization level are investigated.The findings indicate that increasing PCM thickness effectively extends temperature control time,but its impact is limited.The difference in phase change temperature of PCM controls the battery temperature in different temperature ranges.Lower phase change temperatures are unsuitable for controlling battery temperature in high temperature environments.The addition of EG enhances the thermal conductivity of PCM,leading to further control of battery temperature.The results show that the addition of 6%(mass ratio) EG to CPCM extends the effective temperature control time by 11 min and improves by 28% compared to a single PCM.The CPCM utilization is also more satisfactory and achieved a balance between heat storage and thermal conductivity in a battery thermal management system(BTMS) based on PCM.

关键词： phase change material expanded graphite thermal management system effective control time

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Formal Verification of Data Modifications in Cloud Block Storage Based on Separation Logic

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Chinese Journal of Electronics 2024年第1期33卷 112-127页

作者： Bowen ZHANG Zhao JIN Hanpin WANG Yongzhi cao Key Laboratory of High Confidence Software Technologies (MOE) School of Computer Science Peking University School of Computer and Artificial Intelligence Zhengzhou University School of Computer Science and Cyber Engineering Guangzhou University

Cloud storage is now widely used, but its reliability has always been a major concern. Cloud block storage(CBS) is a famous type of cloud storage. It has the closest architecture to the underlying storage and can provide interfaces for other types. Data modifications in CBS have potential risks such as null reference or data loss.Formal verification of these operations can improve the reliability of CBS to some extent. Although separation logic is a mainstream approach to verifying program correctness, the complex architecture of CBS creates some challenges for verifications. This paper develops a proof system based on separation logic for verifying the CBS data modifications. The proof system can represent the CBS architecture, describe the properties of the CBS system state, and specify the behavior of CBS data modifications. Using the interactive verification approach from Coq, the proof system is implemented as a verification tool. With this tool, the paper builds machine-checked proofs for the functional correctness of CBS data modifications. This work can thus analyze the reliability of cloud storage from a formal perspective.

关键词： Formal verification Separation logic Cloud block storage Verification tool Coq