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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 242-254页

作者： Ying Shen Xianfeng Shan Iniobong P.Etim Muhammad Ali Siddiqui Yang Yang Zewen Shi Xuping Su Junxiu chen Key Laboratory of Materials Surface Science and Technology of Jiangsu Province Changzhou UniversityChangzhou213164China Department of Stomatology The Affiliated Xinhua Hospital of Dalian UniversityDalian116000China Department of Physics University of CalabarCalabar540242Nigeria Metallurgical Engineering Department NED University of Engineering and TechnologyUniversity RoadKarachi75270Pakistan Ningbo No.2 Hospital Ningbo315010China

This research systematically examined the degradation,antibacterial effects,and biocompatibility of micro-arc oxidation(MAO)coatings with nano CuO and ZnO on extruded Mg *** copper(Cu)and Zinc(Zn)possess antibacterial *** findings demonstrated that adding ZnO will appreciably reduce the degradation rate of MAO-coating alloy due to the self-sealing micro ***+MAO coating exhibited excellent antibacterial performance,with an antibacterial rate of over 90%within 6 h co-cultured with Staphylococcus ***,the antibacterial rate of ZnO+MAO coating reached 90%after 12 h *** test using MG63 cell indicated that the incorporation of CuO and ZnO did not notably affect the cell viability rate of the ***,after 14 days of culture,the CuO+MAO and ZnO+MAO coated samples exhibited higher alkaline phosphatase(ALP)activity than the MAO-coated and uncoated samples,suggesting favorable osteogenic properties.

关键词： Copper oxide Zinc oxide Micro-arc oxidation(MAO)coating Corrosion behavior Antibacterial characteristics

基于ERA和MCR模型的生态安全格局构建——以陕西沿黄地区为例

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中国环境科学 2024年第2期44卷 1053-1063页

作者：刘瑞宽杨林朋李同昇朱炳臣李炬霖西北大学城市与环境学院陕西西安710127 西北大学陕西省情研究院陕西西安710127

本研究通过构建多风险源指标体系进行陕西沿黄地区生态风险等级评价,利用土地利用数据,探讨研究区近20a的景观结构变化特征;采用“源地—阻力面—廊道”范式构建研究区生态安全格局,确定生态节点和生态断裂点,提出区域生态保护优化建议... 详细信息

本研究通过构建多风险源指标体系进行陕西沿黄地区生态风险等级评价,利用土地利用数据,探讨研究区近20a的景观结构变化特征;采用“源地—阻力面—廊道”范式构建研究区生态安全格局,确定生态节点和生态断裂点,提出区域生态保护优化建议.结果表明:(1)研究区内,生态风险空间分布特征存在显著差异,低值区主要分布在北部和南部,高值区主要分布在中部;(2)研究区近20a生态核心区面积明显增多,但仍然较为破碎,支线占比减少,连通度较低;(3)现有22个重要生态源地,总面积4655.73km^(2),共提取53条重要生态廊道,整体构成“一带三区多廊”的生态安全格局;识别出43个生态节点和98个生态断裂点.其中研究区北部生态廊道和生态节点较为密集.(4)研究区生态网络闭合度低,南北连通性差.未来需要结合区域生态风险等级,通过规划踏脚石斑块、修复生态断裂点、提升9条潜在廊道等方式优化生态安全格局.本研究可为陕西沿黄地区自然生态系统和生物多样性的保护提供科学依据,助力黄河流域生态保护和高质量发展.

关键词：生态风险评价 MSPA模型 MCR模型生态安全格局陕西沿黄地区

Sound Transmission Loss Analysis of a Double Plate-Acoustic Cavity Coupling System with In-Plane Functionally Graded Materials

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Journal of Applied Mathematics and Physics 2024年第6期12卷 2333-2345页

作者： Changzhong chen Mingfei chen Wenliang Yu School of Mechanical Engineering Guizhou University Guiyang China

In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The functionally graded (FG) plate exhibits a different material properties in-plane, and the power-law rule is adopted as the governing principle for material mixing. To validate the harmonic response and demonstrate the accuracy and convergence of the isogeometric modeling, ANASYS is utilized to compare with numerical examples. A plane wave serves as the acoustic excitation, and the Rayleigh integral is applied to discretize the radiated plate. The STL results are compared with the literature, confirming the reliability of the coupling system. Finally, the investigation is conducted to study impact of cavity depth and power-law parameter on the STL.

关键词： Isogeometric Analysis Sound Transmission Loss Double-Plate System Functionally Graded Materials Acoustic Structure Coupling

What can we learn from quality assurance badges in open-source software?

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Science China(Information Sciences) 2024年第4期67卷 146-163页

作者： Feng LI Yiling LOU Xin TAN Zhenpeng chen Jinhao DONG Yang LI Xuanzhi WANG Dan HAO Lu ZHANG MoE Key Lab of HCST School of Computer SciencePeking University Department of Computer Science Purdue University School of Computer Science & Engineering Beihang University(BUAA) Department of Computer Science University College London(UCL)

In the development of open-source software(OSS), many developers use badges to give an overview of the software and share some key features/metrics conveniently. Among various badges, quality assurance(QA) badges make up a large proportion and are the most prevalent because QA is of vital importance in software development, and ineffective QA may lead to anomalies or defects. In this paper, we focus on QA badges in open-source projects, which present quality assurance information directly and instantly,and aim to produce some interesting findings and provide practical implications. We collect and analyze 100000 projects written in popular programming languages from GitHub and conduct a comprehensive empirical study both inside and outside QA badges. Inside QA badges, we build a category classification for all QA badges based on the properties they focus on, which shows the types of QA badges developers use. Then,we analyze the frequency of the properties that QA badges focus on, and property combinations, too, which present their use status. We find that QA badges focus on various properties while developers give different preferences to different properties. The use status also differs between different programming languages. For example, projects written in C focus on Security to a great extent. Our findings also provide implications for developers and badge providers. Outside QA badges, we conduct a correlation analysis between QA badges and some software metrics that have potential relationships with code quality, contribution quality, and popularity. We find that QA badges have statistically significant correlations with various software metrics.

关键词： quality assurance badge open-source software code quality empirical study

Intellicise Model Transmission for Semantic Communication in Intelligence-Native 6G Networks

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China Communications 2024年第7期21卷 95-112页

作者： Wang Yining Han Shujun Xu Xiaodong Meng Rui Liang Haotai Dong chen Zhang Ping State Key Laboratory of Network and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China Department of Broadband Communication Peng Cheng LaboratoryShenzhen 518066China

To facilitate emerging applications and demands of edge intelligence(EI)-empowered 6G networks,model-driven semantic communications have been proposed to reduce transmission volume by deploying artificial intelligence(AI)models that provide abilities of semantic extraction and ***,it is not feasible to preload all AI models on resource-constrained ***,in-time model transmission becomes a crucial *** paper proposes an intellicise model transmission architecture to guarantee the reliable transmission of models for semantic *** mathematical relationship between model size and performance is formulated by employing a recognition error function supported with experimental *** consider the characteristics of wireless channels and derive the closed-form expression of model transmission outage probability(MTOP)over the Rayleigh ***,we define the effective model accuracy(EMA)to evaluate the model transmission performance of both communication and *** we propose a joint model selection and resource allocation(JMSRA)algorithm to maximize the average EMA of all *** results demonstrate that the average EMA of the JMSRA algorithm outperforms baseline algorithms by about 22%.

关键词： edge intelligence(EI) model transmission outage probability and accuracy resource allocation semantic communication

A justice and innovative way ahead of consumption-based emission accounting approach

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Science China Earth Sciences 2024年第10期67卷 2999-3010页

作者： Qun SHEN Hongbo DUAN Yun TANG Linbing TANG Li SHANG Xinyu DOU Wei WEI Weiqiang chen Zhu LIU State Key Laboratory of Low Carbon Catalysis and Carbon Dioxide Utilization CAS Key Laboratory of Low-Carbon Conversion Science&EngineeringShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China School of Economics&Management University of Chinese Academy of SciencesBeijing 100190China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Department of Earth System Science Tsinghua UnivesityBeijing 100084China

Carbon emission accounting is an important basis for global climate *** on the consumption-based accounting(CBA)method,the characteristics of carbon flow between national,regional,and product processes could be more clearly ***,CBA is more conducive to clarifying the attribution of responsibilities between producers and consumers,with the principles of fairness and *** accounting for carbon emissions in typical countries from 1990 to 2019,we found that the CBA emissions are higher than the production-based accounting(PBA)emissions in major developed countries,while the results are reversed for developing *** the past 30 years,the CBA emissions in targeted developed countries generally have shown a downward trend,while in developing countries,they have shown an upward *** emissions in China have shown a continuous growth trend from 1990 to 2019,but the pace has slowed down significantly over the last ***,the embodied carbon intensity of China’s exports continues to decline,indicating that China is providing more green and low-carbon products to the *** the PV industry as an example,this study further reveals the contribution of specific product industries to the country’s carbon transfer through product carbon footprint *** order to provide a scientific basis for global mitigation and climate governance,it is urgent to innovate a scientific,practical,and standardized CBA technology system.

关键词： Consumption-based accounting Production-based accounting Carbon transfer Carbon footprint

基于同步辐射光源X射线散射对聚乙醇酸挤出棒材退火条件的优化

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高分子材料科学与工程 2024年第4期40卷 79-92页

作者：骆佳伟周炳王洪学田雨川陈明明胡永峰中石化(上海)石油化工研究院有限公司上海201208

文中用同步辐射光源对聚乙醇酸(PGA)挤出棒材的切片进行广角X射线散射(WAXS)和小角X射线散射(SAXS)表征,研究聚乙醇酸棒材在挤出成型后优选的退火条件,以尽可能消除内应力,改善棒材后续的机械加工性。WAXS结果表明,高温更有利于微观应... 详细信息

文中用同步辐射光源对聚乙醇酸(PGA)挤出棒材的切片进行广角X射线散射(WAXS)和小角X射线散射(SAXS)表征,研究聚乙醇酸棒材在挤出成型后优选的退火条件,以尽可能消除内应力,改善棒材后续的机械加工性。WAXS结果表明,高温更有利于微观应变的减小,但较高温时晶粒尺寸会随退火时间的延长而减小。SAXS结果表明,高温更有利于取向程度的减小,退火时间对取向程度的影响明显弱于退火温度。综合各数据建立目标函数,并利用响应面分析法进行分析。结果表明,在实验范围内,PGA棒材的优选退火条件为200℃退火2h。

关键词：聚乙醇酸退火同步辐射光源 X射线散射响应面分析法

Improvement of cloud microphysical parameterization and its advantages in simulating precipitation along the Sichuan-Xizang Railway

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Science China Earth Sciences 2024年第3期67卷 856-873页

作者： Xiaoqi XU Zhiwei HENG Yueqing LI Shunjiu WANG Jian LI Yuan WANG Jinghua chen Peiwen ZHANG Chunsong LU China Meteorological Administration Transportation Meteorology Key Laboratory Nanjing Joint Institute for Atmospheric SciencesNanjing 210041China Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province Institute of Plateau MeteorologyCMAChengdu 610072China State Key Laboratory of Disaster Weather Chinese Academy of Meteorological SciencesBeijing 100081China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory and Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science and TechnologyNanjing 210044China

The Sichuan-Xizang Railway is an important part of the railway network in China, and geological disasters, such as mountain floods and landslides, frequently occur in this region. Precipitation is an important cause of these disasters;therefore,accurate simulation of the precipitation in this region is highly important. In this study, the descriptions for uncertain processes in the cloud microphysics scheme are improved;these processes include cloud droplet activation, cloud-rain autoconversion, rain accretion by cloud droplets, and the entrainment-mixing process. In the default scheme, the cloud water content of different sizes corresponds to the same cloud droplet concentration, which is inconsistent with the actual content;this results in excessive cloud droplet size, unreasonable related conversion rates of microphysical process(such as cloud-rain autoconversion), and an overestimation of precipitation. Our new scheme overcomes the problem of excessive cloud droplet size. The processes of cloudrain autoconversion and rain accretion by cloud droplets are similar to the stochastic collection equation, and the mixing mechanism of cloud droplets is more consistent with that occurred during the actual physical process in the cloud. Based on the new and old schemes, multiple precipitation processes in the flood season of 2021 along the Sichuan-Xizang Railway are simulated, and the results are evaluated using ground observations and satellite data. Compared to the default scheme, the new scheme is more suitable for the simulation of cloud physics, reducing the simulation deviation of the liquid water path and droplet radius from 2 times to less than 1 time and significantly alleviating the overestimation of precipitation intensity and range of precipitation center. The average root-mean-square error is reduced by 22%. Our results can provide a scientific reference for improving precipitation forecasting and disaster prevention in this region.

关键词： The Sichuan-Xizang Railway Cloud microphysics Precipitation Model improvement

Machine learning models for the secondary Bjerknes force between two insonated bubbles

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Acta Mechanica Sinica 2021年第1期37卷 35-46,I0001页

作者： Haiyan chen Yue zeng Yi Li School of Material and Energy Guangdong University of TechnologyGuangzhou510006China School of Mathematics and Statistics University of SheffieldSheffieldS37RHUK

The secondary Bjerknes force plays a significant role in the evolution of bubble ***,due to the complex dependence of the force on multiple parameters,it is highly non-trivial to include its effects in the simulations of bubble *** this paper,machine learning is used to develop a data-driven model for the secondary Bjerknes force between two insonated bubbles as a function of the equilibrium radii of the bubbles,the distance between the bubbles,the amplitude and the center frequency of the ultrasound *** sign of the force may change with the phase difference between the oscillating ***,the magnitude of the force varies over several orders of magnitude,which poses a serious challenge for the usual machine learning *** overcome this difficulty,the magnitudes and the signs of the force are separated and modelled separately.A nonlinear regression is obtained with a feed-forward network model for the logarithm of the magnitude,whereas the sign is modelled by a support-vector machine *** principle,the practical aspects related to the training and validation of the machine models are *** predictions from the models are checked against the values computed from the Keller-Miksis *** results show that the models are extremely efficient while providing accurate estimate of the *** models make it computationally feasible for the future simulations of the bubble clusters to include the effects of the secondary Bjerknes force.

关键词： Bubble clusters Secondary Bjerknes force Machine learning Neural networks Support-vector machine Numerical simulations

Emerging hierarchical mesoporous materials of covalent organic frameworks

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Science China Chemistry 2024年第9期67卷 2796-2802页

作者： Lingyan Huang Wenda Li Hongyi Zhang Shanzhe Ke Hao chen Jianwei Fu chengbin Jing Jiangong cheng Shaohua Liu State Key Laboratory of Precision Spectroscopy/Engineering Research Center of Nanophotonics&Advanced Instrument(Ministry of Education) School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450052China State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

Benefiting from abundant exposed active sites,minimized diffusion resistance of guest molecules,facilitated mass transfer process and enhanced storage capacity,covalent organic frameworks(COFs)have gained widespread scientific attention[1–4].Further construction of mesopores regarding pore engineering(pore size,pore geometry,pore volume,and framework compositions)in COFs can improve mass transport,accessibility as well as size-selectivity of the special guest moieties,thus exhibiting potential in catalysis,energy storage and separation and so on[5,6].

关键词： gained catalysis separation