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A coupled thermo-mechanical peridynamic model for fracture behavior of granite subjected to heating and water-cooling processes

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2006-2018页

作者： luming Zhou Zhende Zhu Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China Jiangsu Research Center for Geotechnical Engineering Technology Hohai UniversityNanjing210098China

Thermal damage and thermal fracture of rocks are two important indicators in geothermal mining *** paper investigates the effects of heating and water-cooling on granite specimens at various *** laboratory uniaxial compression experiments were also ***,a coupled thermo-mechanical ordinary state-based peridynamic(OSB-PD)model and corresponding numerical scheme were developed to simulate the damage of rocks after the heating and cooling processes,and the change of crack evolution process was *** results demonstrate that elevated heating temperatures exacerbate the thermal damage to the specimens,resulting in a decrease in peak strength and an increase in ductility of *** escalating occurrence of thermal-induced cracks significantly affects the crack evolution process during the loading *** numerical results accurately reproduce the damage and fracture characteristics of the granite under different final heating temperatures(FHTs),which are consistent with the test results in terms of strength,crack evolution process,and failure mode.

关键词： Peridynamics(PD) Granite Heating and cooling Damage and fracture Uniaxial compression

A review of ^(17)O isotopic labeling techniques for solid-state NMR structural studies of metal oxides in lithium-ion batteries

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Magnetic Resonance Letters 2024年第2期4卷 46-53页

作者： Xiaoli Xia Lei Zhu Weiping Tang luming Peng Junchao Chen School of Chemistry and Chemical Engineering Shanghai Jiao Tong University800 Dongchuan RoadShanghai200240China Key Laboratory of Mesoscopic Chemistry of Ministry of Education and Collaborative Innovation Center of Chemistry for Life Sciences School of Chemistry and Chemical EngineeringNanjing University163 Xianlin RoadNanjing210023China State Key Laboratory of Space Power-Sources Technology Shanghai Institute of Space Power-SourcesShanghai200245China

Recent advances in utilizing ^(17)O isotopic labeling methods for solid-state nuclear magnetic resonance(NMR)investigations of metal oxides for lithium-ion batteries have yielded extensive insights into their structural and dynamic ***,we commence with a brief introduction to recent research on lithium-ion battery oxide materials studied using ^(17)O solid-state NMR *** we delve into a review of ^(17)O isotopic labeling methods for tagging oxygen sites in both the bulk and surfaces of metal *** last,the unresolved problems and the future research directions for advancing the ^(17)O labeling technique are discussed.

关键词： ^(17)O solid-state NMR ^(17)O isotopic labeling methods Bulk and surfaces of metal oxides DFT calculation

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Bicarbonate used as a buffer for controlling nutrient solution pH value during the growth of hydroponic lettuce

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 59-67页

作者： mengxue Zhang Wenxin Wang luming Zhong Fang Ji Dongxian He Key Laboratory of Agricultural Engineering in Structure and Environment of MARA College of Water Resources&Civil EngineeringChina Agricultural UniversityBeijing 100083China

Unstable pH of nutrient solution in hydroponic systems is a major obstacle to *** simplify the management of nutrient solution pH and attenuate negative effects of pH on plant growth,this study investigated the effect of different buffer salt additions on nutrient solution pH,ion uptake,growth and photosynthesis of Yamazaki lettuce,with the equivalent concentrations of macro-element *** results indicated that the pH of nutrient solution was buffered to varying degrees by the 2 mol/L HCO_(3)^(-),1 mol/L HCO_(3)^(-),and 0.33 mol/L HPO_(4)^(2-)The 0.33 mol/L HPO_(4)^(2-)treatment fluctuated most with a pH of 1.74 units,while the addition of HCO_(3)^(-)buffered nutrient solution pH was better,with higher pH values(7.2-7.7).The CK-pH control solution,1 mol/L HCO_(3)^(-)and 0.33 mol/L HPO_(4)^(2-)treatments all promoted the uptake of ion and then the growth of lettuce was better in comparison with the CK-pH no adjustment treatment,while the 2 mol/L HCO_(3)^(-)treatment inhibited K uptake and reduced the availability of Fe,the shoot and root fresh weight of lettuce decreased by 21.3%and 10.1%,*** addition,although the chlorophyll content and net photosynthetic rate under 1 mol/L HCO_(3)^(-)and 0.33 mol/L HPO_(4)^(2-)treatments were significantly lower than the CK-pH control solution treatment,there were no significant differences in leaf length and leaf number of lettuce among them,and shoot fresh weight per plant was 83.09,82.95,and 78.92 g,*** conclusion,adding 1 mol/L HCO_(3)^(-)to the nutrient solution in a single dosage not only buffered the pH of nutrient solution better but also promoted ion uptake,it had no negative effects on the growth,photosynthesis and ion uptake of hydroponic lettuce in comparison with the CK-pH control solution ***,1 mol/L HCO_(3)^(-)can be used as a buffer during the growth of hydroponic lettuce and reduce frequent addition of acids or alkalis,and then simplify the management of nut

关键词： pH buffer nutrient solution hydroponic lettuce growth ion uptake

Kinetics-Controlled Amphiphiles Self-Assembly Processes

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Kinetics-Controlled Amphiphiles Self-Assembly Processes

Unraveling the role of iron on Ni-Fe alloy nanoparticles during the electrocatalytic ethanol-to-acetate process

第十三届全国量子化学会议

作者： Xiaoyan Zheng Lizhe Zhu Xiangze Zeng luming meng Lu Zhang Dong Wang Xuhui Huang Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration & ReconstructionHong Kong University of Science and Technology

Amphiphiles self-assembly is an essential bottom-up approach of fabricating advanced functional materials. Self-assembled materials with desired structures are often obtained through thermodynamic control. Here, we demonstrate that the selection of kinetic pathways can lead to drastically different self-assembled structures, underlining the significance of kinetic control in self-assembly. By constructing kinetic network models from large-scale molecular dynamics simulations1, we show that two largely similar amphiphiles PYR and PYN prefer distinct kinetic assembly pathways. While PYR prefers an incremental growth mechanism and forms a nanotube, PYN favors a hopping growth pathway leading to a vesicle. Such preference was found to originate from the subtle difference in the distributions of hydrophobic and hydrophilic groups in their chemical structures, which leads to different rates of the adhesion process among the aggregating micelles. Our results are in good agreement with experimental results, and accentuate the role of kinetics in the rational design of amphiphiles self-assembly.

关键词： Kinetics-Controlled Amphiphiles Self-Assembly Processes

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Nano Research 2024年第4期17卷 2328-2336页

作者： Junshan Li luming Li Xinyu Ma Jun Wang Jun Zhao Yu Zhang Ren He Yaoyue Yang Andreu Cabot Yongfa Zhu Institute for Advanced Study Chengdu University610106 ChengduChina State Key Laboratory of Environmental-Friendly Energy Materials Southwest University of Science and TechnologyMianyang 621010China College of Food and Biological Engineering Chengdu UniversityChengdu 610106China School of Chemistry and Environment Southwest Minzu UniversityChengdu 610041China Hebei Key Laboratory of Photoelectric Control on Surface and Interface College of ScienceHebei University of Science and TechnologyShijiazhuang 050018China Catalonia Institute for Energy Research-IREC Sant Adriàde BesòsBarcelona 08930CataloniaSpain ICREA Pg.Lluís Companys 23Barcelona 08010CataloniaSpain Department of Chemistry Tsinghua UniversityBeijing 100084China

The anodic electrooxidation of ethanol to value-added acetate is an excellent example of replacing the oxygen evolution reaction to promote the cathodic hydrogen evolution reaction and save ***,we present a colloidal strategy to produce Ni-Fe bimetallic alloy nanoparticles(NPs)as efficient electrocatalysts for the electrooxidation of ethanol in alkaline ***-Fe alloy NPs deliver a current density of 100 mA·cm^(-2) in a 1.0 M KOH solution containing 1.0 M ethanol merely at 1.5 V *** hydrogen electrode(RHE),well above the performance of other electrocatalysts in a similar *** continuous 10 h testing at this external potential,this electrode is able to produce an average of 0.49 mmol·cm^(-2)·h^(-1) of acetate with an ethanol-to-acetate Faradaic efficiency of 80%.A series of spectroscopy techniques are used to probe the electrocatalytic process and analyze the ***,density functional theory(DFT)calculations demonstrate that the iron in the alloy NPs significantly enhances the electroconductivity and electron transfer,shifts the rate-limiting step,and lowers the energy barrier during the ethanol-to-acetate reaction pathway.

关键词： electrocatalysis ethanol oxidation reaction alloy nanoparticle acetate biorefinery

Enhancing alkaline water oxidation with NiFe alloy-encapsulated nitrogen-doped vertical graphene array

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Nano Research 2024年第6期17卷 4790-4796页

作者： Jue Nan Beirong Ye Xun He Chen Li Wanli Zhang Qian Liu luming Li Wei Chu Xuping Sun Yongqi Zhang School of Integrated Circuit Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Institute of Fundamental and Frontier Science University of Electronic Science and Technology of ChinaChengdu 611731China Institute for Advanced Study Chengdu UniversityChengdu 610106China College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJinan 250014China

Advancing efficient and affordable electrocatalysts to boost the oxygen evolution reaction(OER)is pivotal for sustainable green hydrogen ***,we propose the fabrication of nickel-iron alloy nanoparticles-encapsulated on N-doped vertically aligned graphene array on carbon cloth(NiFe@NVG/CC)as a highly active three-dimensional(3D)catalyst electrode for *** 1 M KOH,such NiFe@NVG/CC demonstrates outstanding catalytic performance,necessitating merely overpotential of 245 mV for achieving a current density of 10 mA·cm^(−2),a remarkably low Tafel slope of 36.2 mV·dec^(−1).Furthermore,density functional theory calculations validate that the incorporate of N species into graphene can reinforce the electrocatalytic activity though reducing the reaction energy barrier during the conversion of*O to*OOH *** outstanding performance and structural benefits of NiFe@NVG/CC offer valuable insights for the development of innovative and efficient electrocatalysts for water oxidation.

关键词： NiFe alloy N-doped vertical graphene array electrocatalyst oxygen evolution reaction density functional theory

Enhancing Code Quality with LLM in Software Static Analysis

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ZTE Communications 2024年

作者： NIU Zhi DONG luming State Key Laboratory of Mobile Network and Mobile Multimedia Technology ZTE Corporation

In our modern age of omnipresent and highly interconnected information technology， cybersecurity caused by software code vulnerabilities becomes ever more challenged， threatening the confidentiality， integrity， and availability of information systems during operation. To enhance software code quality， enterprises often incorporate static code analysis tools in Continuous Integration (CI) pipelines. but the side effects of high false positives and false negatives remain a challenge. The advent of LLM like ChatGPT AI model presents an opportunity to address this challenge. In this paper， we propose a method utilizing the custom-built Nebula-coder AI model for detecting and fixing code security issues in real-time during the developer’s personal build process. We construct a static code checking rule knowledge base through summarizing and classifying CWE code security problems identified by security teams and quality assurance teams. The rule knowledge base is combined with CodeFuse-processed code contexts to serve as inputs for an AI code security detection microservice， which assists in identifying code quality and security issues. If any abnormalities are detected， they are addressed by an AI code security patching microservice， which alerts the developer and requests confirmation before committing the code into the repository. Experimental results show that our approach effectively improves code quality. We developed a VSCode plugin for code alert detection and repair based on LLMs， which facilitates test shift-left and lowers the risk of software development.

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Multi-network-region traffic cooperative scheduling in large-scale LEO satellite networks

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Journal of Systems Engineering and Electronics 2024年第4期35卷 829-841页

作者： LI Chengxi WANG Fu YAN Wei CUI Yansong FAN Xiaodong ZHU Guangyu XIE Yanxi YANG Lixin ZHOU luming ZHAO Ran WANG Ning School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China The 6th Research Institute of China Electronics Corporation Beijing 102209China China Satellite Network Share Operation Co. LtdBeijing 100876China Weihai Electronic Information Technology Comprehensive Research Center of the Ministry of Industry and Information Technology Weihai 264200 China

A low-Earth-orbit(LEO)satellite network can provide full-coverage access services worldwide and is an essential candidate for future 6G ***,the large variability of the geographic distribution of the Earth’s population leads to an uneven service volume distribution of access ***,the limitations on the resources of satellites are far from being able to serve the traffic in hotspot *** enhance the forwarding capability of satellite networks,we first assess how hotspot areas under different load cases and spatial scales significantly affect the network throughput of an LEO satellite network ***,we propose a multi-region cooperative traffic scheduling *** algorithm migrates low-grade traffic from hotspot areas to coldspot areas for forwarding,significantly increasing the overall throughput of the satellite network while sacrificing some latency of end-to-end *** algorithm can utilize all the global satellite resources and improve the utilization of network *** model the cooperative multi-region scheduling of large-scale LEO *** on the model,we build a system testbed using OMNET++to compare the proposed method with existing *** simulations show that our proposed method can reduce the packet loss probability by 30%and improve the resource utilization ratio by 3.69%.

关键词： low-Earth-orbit(LEO)satellite network satellite communication load balance multi-region scheduling latency optimization

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Control of GaN inverted pyramids growth on c-plane patterned sapphire substrates

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Journal of Semiconductors 2024年第6期45卷 92-96页

作者： luming Yu Xun Wang Zhibiao Hao Yi Luo Changzheng Sun Bing Xiong Yanjun Han Jian Wang Hongtao Li Lin Gan Lai Wang Beijing National Research Center for Information Science and Technology Department of Electronic EngineeringTsinghua UniversityBei-jing 100084China Center for Flexible Electronics Technology Tsinghua UniversityBeijing 100084China

Growth of gallium nitride(GaN)inverted pyramids on c-plane sapphire substrates is benefit for fabricating novel devices as it forms the semipolar *** this work,GaN inverted pyramids are directly grown on c-plane patterned sapphire substrates(PSS)by metal organic vapor phase epitaxy(MOVPE).The influences of growth conditions on the surface morphol-ogy are experimentally studied and explained by Wulff *** competition of growth rate among{0001},{1011},and{1122}facets results in the various surface morphologies of GaN.A higher growth temperature of 985 ℃ and a lowerⅤ/Ⅲratio of 25 can expand the area of{}facets in GaN inverted *** the other hand,GaN inverted pyramids with almost pure{}facets are obtained by using a lower growth temperature of 930℃,a higherⅤ/Ⅲratio of 100,and PSS with pattern arrangement perpendicular to the substrate primary flat.

关键词： inverted pyramids GaN MOVPE crystal growth competition model

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