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Recent advances in high-temperature oxidation behavior and underlying mechanisms of Mg-RE alloys:A comprehensive review
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作者 yu Ma yu cao +4 位作者 yulian Kuang Yajun Wang yuhao Gong Bin Jiang Jonghyun Kim 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期446-466,共21页
The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical pr... The limited high-temperature oxidation resistance of Mg alloys is a key factor restricting their development and application.The addition of some rare earth elements(REs),owing to their unique physical and chemical properties,can significantly enhance the oxidation resistance of Mg alloys.Based on our previous study,we conclude that REs such as Gd,Y,and Ce enhance the oxidation resistance of Mg-RE alloys.This article comprehensively reviews recent research progress on high-temperature oxidation behavior and the potential mechanism in Mg-RE alloys.Based on the thermodynamic and kinetic analyses,the evolution of the complex oxide system formed during the high-temperature oxidation of Mg-RE alloys is first summarized.The diffusion behavior and concentration control mechanisms of REs during the oxidation process and how these mechanisms affect the sustained growth of the oxide film and antioxidant properties were elucidated.Moreover,the different structures of the oxide films were classified,and their properties were discussed.Finally,this paper introduces the applications of commonly used REs in Mg alloys and frontier research on their oxidation mechanisms.Based on the above review,we propose that future research perspectives can be explored in terms of expanding the experimental temperature range for oxidation tests,optimizing the chemical composition by adding trace REs to study their synergistic mechanism,revealing the underlying oxidation mechanism through advanced in situ microscopic characterization methods,and investigating the mechanical properties of oxide films using diverse approaches. 展开更多
关键词 magnesium-rare earth element alloy high-temperature oxidation THERMODYNAMICS oxidation resistance oxide films
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双边市场网约车平台聚合策略选择研究 被引量:4
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作者 曹裕 李想 李青松 《中国管理科学》 北大核心 2025年第4期142-153,共12页
以网约车双边市场为背景,结合双边市场理论以及Hotelling模型构建双寡头平台竞争模型,分析一个由聚合平台中的小平台集合(A)与一个大平台(B)的竞争均衡,研究不同网络外部性强度与用户旅行成本的大平台聚合策略选择问题。理论推导了不聚... 以网约车双边市场为背景,结合双边市场理论以及Hotelling模型构建双寡头平台竞争模型,分析一个由聚合平台中的小平台集合(A)与一个大平台(B)的竞争均衡,研究不同网络外部性强度与用户旅行成本的大平台聚合策略选择问题。理论推导了不聚合策略(N)、跟随策略(F)与开放策略(O)下的双边市场规模决策、定价决策以及定价对用户转移的影响。进一步,通过数值模拟比较不同聚合策略下的大平台利润,发现交叉网络外部性与用户旅行成本是影响大平台聚合策略选择的重要因素。当用户端和司机端交叉网络外部性均低时,大平台不参与聚合,随着外部性上升,其选择会从跟随策略转变为开放策略,其中用户端网络外部性对跟随策略、司机端网络外部性对开放策略作用更为显著;当用户旅行成本低于阈值时,大平台采取跟随策略,否则不参与聚合。有趣的是,司机旅行成本和聚合平台抽成比例均不会影响大平台聚合策略选择,可为现实中聚合平台前期的免抽成策略做出解释。 展开更多
关键词 双边市场 网约车平台 聚合策略 交叉网络外部性
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基于分子模拟的页岩油气多相赋存机理
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作者 屈洋 余曹 +3 位作者 杨洋 于海生 王青振 康鑫 《大庆石油地质与开发》 北大核心 2025年第6期167-174,共8页
无机矿物作为页岩油层主要成分,是油气吸附的重要载体,因此研究油气在无机纳米孔隙中的赋存机理十分重要。采用分子模拟技术,通过构建页岩无机矿物和油气分子模型,剖析页岩油气的多相赋存机制,模拟不同温度、压力条件下甲烷、戊烷、癸... 无机矿物作为页岩油层主要成分,是油气吸附的重要载体,因此研究油气在无机纳米孔隙中的赋存机理十分重要。采用分子模拟技术,通过构建页岩无机矿物和油气分子模型,剖析页岩油气的多相赋存机制,模拟不同温度、压力条件下甲烷、戊烷、癸烷、十五烷等油气分子与二氧化硅矿物表面的相互作用。结果表明:低温下分子扩散慢,有利于吸附平衡,高温下以解吸为主,温度越高,流体与矿物表面之间的范德华力越小,越有利于流体解吸脱附,从而提高油气藏动用程度;高压下分子间距减小,页岩油分子与页岩固体表面的范德华作用增强,导致页岩油吸附量显著增加;轻烃分子可动率大于重烃分子,当孔隙直径增加到12 nm时,小分子烷烃(C_(1)、C_(5))动用率可达到约80%,而长链烷烃(C_(10)、C_(15))只能达到约60%。研究成果可为页岩油气藏储量评估、开采方案优化提供理论支撑。 展开更多
关键词 分子模拟 烷烃 吸附 二氧化硅 页岩油 密度分布
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掺氢环境下X52管道氢损劣化性研究
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作者 鲍明昱 高健 +5 位作者 曹辉祥 张健 刘畅 于操 帅健 梅苑 《安全与环境学报》 北大核心 2025年第7期2603-2611,共9页
在氢管道运行过程中,气态原子氢的渗入会诱发管材氢损,导致管道失效风险加剧。为了有效评估管道掺氢输送的安全性,搭建了满足氢渗透特性及氢脆劣化性的试验平台,以此开展X52管道的氢损劣化性研究。结果表明,氢分压的提高会导致管材表面... 在氢管道运行过程中,气态原子氢的渗入会诱发管材氢损,导致管道失效风险加剧。为了有效评估管道掺氢输送的安全性,搭建了满足氢渗透特性及氢脆劣化性的试验平台,以此开展X52管道的氢损劣化性研究。结果表明,氢分压的提高会导致管材表面下原子氢浓度累积并呈现非线性的提升,这会造成管材氢损加剧,氢损特征表征提前。与此同时,缺口效应也会进一步放大氢损特征的表征程度。此外,基于试验结果,构建了管材氢损损减与原子氢累积情况之间关系的预测公式,为未来管道掺氢后的安全评价提供了数据基础。从微观层面揭示了掺氢环境下管材断裂模式的转变关系,发现缺陷条件显著增加了管材基体原有的氢损程度及影响范围。研究结果可为X52管道掺氢运输的建设及防护提供相应的参考。 展开更多
关键词 安全工程 掺氢环境 X52管道 氢脆 安全评价
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从“血不化精”论治顽固性血精
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作者 俞操 李亚妤 +2 位作者 蒋筱 王权胜 陈豪特 《中国性科学》 2025年第4期103-106,共4页
顽固性血精属于中医“精血”范畴,现代中医多从瘀热、湿热论治。蒋筱教授从“血不化精”的角度出发,认为心肾阳衰、气滞血瘀致使“血不化精”是该病的重要病机。患者由于病程长、情志拂郁、思欲无度多发多虚多瘀之变,临证时需根据患者... 顽固性血精属于中医“精血”范畴,现代中医多从瘀热、湿热论治。蒋筱教授从“血不化精”的角度出发,认为心肾阳衰、气滞血瘀致使“血不化精”是该病的重要病机。患者由于病程长、情志拂郁、思欲无度多发多虚多瘀之变,临证时需根据患者或虚或郁的证候,或以心肾之阳为本,或以疏肝解郁、和畅精室气机为用,兼以止血宁血,知常达变,随证治之,灵活用药,常获良效。 展开更多
关键词 血精 顽固性血精 “血不化精” 经验 蒋筱
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A Trusted Distributed Oracle Scheme Based on Share Recovery Threshold Signature 被引量:1
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作者 Shihao Wang Xuehui Du +4 位作者 Xiangyu Wu Qiantao Yang Wenjuan Wang yu cao Aodi Liu 《Computers, Materials & Continua》 2025年第2期3355-3379,共25页
With the increasing popularity of blockchain applications, the security of data sources on the blockchain is gradually receiving attention. Providing reliable data for the blockchain safely and efficiently has become ... With the increasing popularity of blockchain applications, the security of data sources on the blockchain is gradually receiving attention. Providing reliable data for the blockchain safely and efficiently has become a research hotspot, and the security of the oracle responsible for providing reliable data has attracted much attention. The most widely used centralized oracles in blockchain, such as Provable and Town Crier, all rely on a single oracle to obtain data, which suffers from a single point of failure and limits the large-scale development of blockchain. To this end, the distributed oracle scheme is put forward, but the existing distributed oracle schemes such as Chainlink and Augur generally have low execution efficiency and high communication overhead, which leads to their poor applicability. To solve the above problems, this paper proposes a trusted distributed oracle scheme based on a share recovery threshold signature. First, a data verification method of distributed oracles is designed based on threshold signature. By aggregating the signatures of oracles, data from different data sources can be mutually verified, leading to a more efficient data verification and aggregation process. Then, a credibility-based cluster head election algorithm is designed, which reduces the communication overhead by clarifying the function distribution and building a hierarchical structure. Considering the good performance of the BLS threshold signature in large-scale applications, this paper combines it with distributed oracle technology and proposes a BLS threshold signature algorithm that supports share recovery in distributed oracles. The share recovery mechanism enables the proposed scheme to solve the key loss issue, and the setting of the threshold value enables the proposed scheme to complete signature aggregation with only a threshold number of oracles, making the scheme more robust. Finally, experimental results indicate that, by using the threshold signature technology and the cluster head election algorithm, our scheme effectively improves the execution efficiency of oracles and solves the problem of a single point of failure, leading to higher scalability and robustness. 展开更多
关键词 Blockchain threshold signature distributed oracle data submission share recovery
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Punicalagin alleviates hypercholesterolemia in mice through modulating farnesoid X receptor signaling and modulating gut microbiota 被引量:1
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作者 Huanhuan Liu Hongli Liu +4 位作者 Chunhong Yan Jiaxiu Liu yu cao Guopeng Li Xiaodong Xia 《Food Science and Human Wellness》 2025年第1期175-189,共15页
Punicalagin has been demonstrated to exhibit anti-oxidant and anti-inflammatory properties,but whether and how it could impact hypercholesterolemia remains not fully explored.The aim of this study was to investigate t... Punicalagin has been demonstrated to exhibit anti-oxidant and anti-inflammatory properties,but whether and how it could impact hypercholesterolemia remains not fully explored.The aim of this study was to investigate the influence of punicalagin on hypercholesterolemia in mice and its related mechanisms.After 6 weeks'intervention,punicalagin significantly reduced serum total cholesterol and low-density lipoprotein cholesterol(LDL-C)levels in mice fed a high-fat high-cholesterol(HFHC)diet.Meanwhile,punicalagin supplementation lowered hepatic cholesterol level,which corresponded to the down-regulation of cholesterol synthesis genes(Fdps,Cyp51)and up-regulated bile acid synthesis genes(Cyp7a1,Cyp27a1).In addition,bile acid reabsorption was retarded in punicalagin-fed mice through down-regulating ileal apical sodium-dependent BA transporter(ASBT).Furthermore,intestinal farnesoid X receptor(FXR)-fibroblast growth factor 15(Fgf15)pathway was inhibited while hepatic FXR-small heterodimeric partner(SHP)pathway was activated in punicalagin group.Microbiota analysis and targeted metabolomics showed that punicalagin decreased the abundance of bile-salt hydrolase(BSH)-producing bacteria(Clostridiaceae and Bifidobacteriaceae)and the ratio of primary BAs to secondary BAs.In conclusion,the cholesterol-lowering effect of punicalagin partly through down-regulating cholesterol synthesis and increasing cholesterol catabolism,which could be achieved by regulating gut microbiota,altering bile acid composition and modulating FXR signaling pathway.These findings indicate the potential application of punicalagin-related products as an alternative strategy for hypercholesterolemia prevention and mitigation. 展开更多
关键词 PUNICALAGIN HYPERCHOLESTEROLEMIA Farnesoid X receptor Bile acid metabolism Gut microbiota
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Terpinen-4-ol suppresses proliferation and motility of cutaneoussquamous cell carcinoma cells by enhancing calpain-2 expression 被引量:1
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作者 DONGyuN RONG yuSHEN SU +3 位作者 ZHIRUI ZENG YAN YANG HONGUAN LU yu cao 《Oncology Research》 2025年第3期605-616,共12页
Background:Terpinen-4-ol(T4O),a key constituent of tea tree essential oil and various aromatic plants,has shown promising antiproliferative and pro-apoptotic effects in melanoma and other cancer types.However,its effi... Background:Terpinen-4-ol(T4O),a key constituent of tea tree essential oil and various aromatic plants,has shown promising antiproliferative and pro-apoptotic effects in melanoma and other cancer types.However,its efficacy against cutaneous squamous cell carcinoma(cSCC)remains unclear.Thus,in this study,we investigated the in vivo and in vitro effects of T4O on cSCC cell lines and preliminarily explored its impacting pathways.Methods:Using CCK8 and assay colony formation,we assessed the viability of cSCC A431,SCL-1,and COLO-16 cells treated with T40 at varying concentrations(0,1,2,and 4μM).Flow cytometry was employed to evaluate T4O’s effect on cSCC cell’s cycle progression and apoptosis induction.Additionally,western blotting was utilized to examine the expression intensities of N-cadherin and E-cadherin,two indicative markers of the epithelial-mesenchymal transition(EMT)pathway.T4O’s in vivo effect on inhibiting tumor progression was evaluated on an established xenograft tumor model.Then,the molecular mechanisms of T4O’s antitumor effect were explored by an integrated genome-wide transcriptomics and proteomics study on cSCC A431c cells.Finally,calpain-2’s potential mediator role in T4O’s anti-tumor mechanism was investigated in calpain-2 knockdown cell lines prepared via siRNA transfection.Result:It’s demonstrated that T4O treatment inhibited cSCC proliferation,clonogenicity,migration,and invasion while inducing apoptosis and suppressing the EMT pathway.T4O administration also inhibited cSCC tumorigenesis in the xenograft tumor model.RNA-sequencing and iTRAQ analysis detected significant upregulation of calpain-2 expression in T4O-treated cSCC cells.Western blotting confirmed that T4O significantly increased calpain-2 expression and promoted proteolytic cleavage ofβ-catenin and caspase-12,two calpain-2 target proteins.Importantly,siRNA-mediated calpain-2 knockdown relieved T4O’s suppressive effect on cSCC cell proliferation and motility.Mechanistically,T4O upregulates calpain-2 expression and promotes the cleavage ofβ-catenin and caspase-12,with siRNA-mediated calpain-2 knockdown mitigating T4O’s suppressive effects.Conclusion:These findings suggest that T4O’s antitumor activity in cSCC is mediated through the upregulation of calpain-2 expression and subsequent modulation ofβ-catenin and caspase-12. 展开更多
关键词 Cutaneous squamous cell carcinoma(cSCC) Terpinen-4-ol(T4O) Calpain-2(CAPN2) Mouse xenograft Apoptosis
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油气管道焊接技术现状及发展趋势
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作者 林睿南 熊猛 +1 位作者 于操 杨苓锦 《西安石油大学学报(自然科学版)》 北大核心 2025年第2期95-105,共11页
石油天然气是国家能源战略安全的基本保障,管道建设与管道安全服役、高效利用是油气储运发展的核心。管道焊接技术直接影响整个管道系统的安全性能、工程质量以及施工成本等,管道焊接技术成为管道工程建设、油气输送研究的重点。通过总... 石油天然气是国家能源战略安全的基本保障,管道建设与管道安全服役、高效利用是油气储运发展的核心。管道焊接技术直接影响整个管道系统的安全性能、工程质量以及施工成本等,管道焊接技术成为管道工程建设、油气输送研究的重点。通过总结国内外管道焊接技术特点、发展现状和关键设备,分析了在困难段施工时管道焊接的方案,探讨了管道焊接工艺、装备和相关标准的发展趋势。 展开更多
关键词 管道焊接 焊接工艺 焊接设备 焊缝检测 安全评价
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Plant natural products as effective options for inhibiting foodborne pathogens: a comprehensive review of their activities, mechanisms, and applications in food preservation
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作者 Menglong Liu Haiyan Ding +3 位作者 yu cao Lijing Liu Qiaoli Xue Yongjin Hu 《Food Science and Human Wellness》 2025年第9期3388-3413,共26页
In order to ensure food safety,controlling foodborne pathogen contamination is of utmost importance.Growing apprehensions regarding the safety of synthetic antimicrobials,due to their adverse health effects,have promp... In order to ensure food safety,controlling foodborne pathogen contamination is of utmost importance.Growing apprehensions regarding the safety of synthetic antimicrobials,due to their adverse health effects,have prompted a search for alternative options.Plant natural products(PNPs)with antimicrobial activity are being explored as a viable alternative.Among the various antimicrobial natural products studied,plant essential oils,plant flavonoids,plant polyphenols,plant polysaccharides,and plant antimicrobial peptides have been identified as potential candidates.PNPs demonstrate a diverse array of antimicrobial mechanisms,encompassing cell wall and membrane damage,interference with genetic replication,disruption of energy metabolism,and induction of oxidative stress at the single-cell level,as well as inhibition of biofilm formation and quorum sensing at the population level.Certain PNPs have been harnessed as natural antimicrobial agents for the food preservation.The utilization of encapsulation technology proves to be an effective strategy in protecting PNPs,thereby ensuring good antimicrobial efficacy,enhanced dispersibility,and controlled release within food products.The utilization of nanoemulsions,nanoliposomes,edible packaging,electrospun nanofibers,and microcapsules formed by encapsulation has enriched the ways in which PNPs can be applied in food preservation.Although PNPs have great potential in food preservation,their widespread application in the food industry is currently constrained by factors such as production costs,safety concerns,and legal considerations.Chemical synthesis and biosynthesis pathways offer viable strategies for reducing the cost of producing PNPs,and ongoing efforts to assess safety and improve regulatory frameworks are likely to facilitate the broader adoption of PNPs in food preservation practices.This article provides an overview of the main types of PNPs with antimicrobial activity and their properties,focusing on their mechanisms of action.Additionally,it summarizes the use of PNPs in food preservation and discusses the characteristics and applications of different encapsulation technologies.Lastly,the paper briefly analyzes current limitations and proposes potential future trends for this field. 展开更多
关键词 Plant natural products Foodborne pathogens Antimicrobial activity Antimicrobial mechanism Food preservation ENCAPSULATION
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Competitive roles of slow/delta oscillation-nesting-mediated sleep disruption under acute methamphetamine exposure in monkeys
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作者 Xin LV Jie LIU +6 位作者 Shuo MA yuhan WANG Yixin PAN Xian QIU yu cao Bomin SUN Shikun ZHAN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第7期694-707,共14页
Abuse of amphetamine-based stimulants is a primary public health concern.Recent studies have underscored a troubling escalation in the inappropriate use of prescription amphetamine-based stimulants.However,the neuroph... Abuse of amphetamine-based stimulants is a primary public health concern.Recent studies have underscored a troubling escalation in the inappropriate use of prescription amphetamine-based stimulants.However,the neurophysiological mechanisms underlying the impact of acute methamphetamine exposure(AME)on sleep homeostasis remain to be explored.This study employed non-human primates and electroencephalogram(EEG)sleep staging to evaluate the influence of AME on neural oscillations.The primary focus was on alterations in spindles,delta oscillations,and slow oscillations(SOs)and their interactions as conduits through which AME influences sleep stability.AME predominantly diminishes sleep-spindle waves in the non-rapid eye movement 2(NREM2)stage,and impacts SOs and delta waves differentially.Furthermore,the competitive relationships between SO/delta waves nesting with sleep spindles were selectively strengthened by methamphetamine.Complexity analysis also revealed that the SO-nested spindles had lost their ability to maintain sleep depth and stability.In summary,this finding could be one of the intrinsic electrophysiological mechanisms by which AME disrupted sleep homeostasis. 展开更多
关键词 AMPHETAMINE Sleep stage Slow oscillation(SO) Delta oscillation Addiction Electroencephalogram(EEG)
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Modulating dangling anions coordination upon polyanionic fluorophosphate cathode to achieve high-voltage sodium-ion batteries
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作者 Yin-Qi Zheng Jing-Jing Hou +10 位作者 Jia-Ji Tang Mei-Yan Sun Shi-Zhong Lv Li-Ting Wang yu cao Zao-Hui He Ai-Min Lv Liang Deng Guang-yu Zhao Lei Zhao Zhen-Bo Wang 《Journal of Energy Chemistry》 2025年第11期614-624,I0015,共12页
NASICON-type vanadium fluorophosphate is a promising cathode for sodium-ion batteries.Yet,the thermally-driven loss of undercoordinated dangling fluorine anions weakens its structural stability,which triggers severe f... NASICON-type vanadium fluorophosphate is a promising cathode for sodium-ion batteries.Yet,the thermally-driven loss of undercoordinated dangling fluorine anions weakens its structural stability,which triggers severe framework distortion from interconnected double-octahedral to isolated local octahedral units,as well as a degeneracy of t_(2g) electronic configuration of vanadium(V)3d orbit.In this work,it is clarified that such a degenerate state undergoes spontaneous lattice evolution to reduce the system energy,which causes a low crystalline symmetry and a parasitic V^(4+)/V^(3+)redox reaction in the low-voltage region.Herein,an anion-coordination regulation strategy is developed to suppress this degeneration by anchoring fluorine anions in the double-octahedral[V_(2)O_(8)F_(3)]framework.Density functional theory calculations and in-situ techniques track the F-anion-driven structural evolution and charge compensation mechanisms,revealing that this strategy mitigates detrimental phase segregation during the initial desodiation stage and enhances the Na^(+)diffusion kinetic rate over a factor of 100.Concurrently,this strategy releases the V^(4+)/V^(3+)redox kinetics by eliminating the parasitic low-voltage plateau.The full-cell assembled with the optimized fluorophosphate cathode delivers an increase of 50%in discharge capacity and stable two-voltage-plateau behavior,enabled by its double-octahedral[V_(2)O_(8)F_(3)]polyanionic structure that facilitates unimpeded three-dimensional(3D)Na^(+)transport.By correlating anion-coordination stability with orbital-level charge compensation,this work establishes a universal paradigm for highperformance polyanionic cathodes,positioning it as a competitive candidate for battery applications. 展开更多
关键词 Dangling anions F Anion-coordination regulation High voltage CATHODE Sodium ion batteries
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Intelligent Detection of Abnormal Traffic Based on SCN-BiLSTM
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作者 Lulu Zhang Xuehui Du +3 位作者 Wenjuan Wang yu cao Xiangyu Wu Shihao Wang 《Computers, Materials & Continua》 2025年第7期1901-1919,共19页
To address the limitations of existing abnormal traffic detection methods,such as insufficient temporal and spatial feature extraction,high false positive rate(FPR),poor generalization,and class imbalance,this study p... To address the limitations of existing abnormal traffic detection methods,such as insufficient temporal and spatial feature extraction,high false positive rate(FPR),poor generalization,and class imbalance,this study proposed an intelligent detection method that combines a Stacked Convolutional Network(SCN),Bidirectional Long Short-Term Memory(BiLSTM)network,and Equalization Loss v2(EQL v2).This method was divided into two components:a feature extraction model and a classification and detection model.First,SCN was constructed by combining a Convolutional Neural Network(CNN)with a Depthwise Separable Convolution(DSC)network to capture the abstract spatial features of traffic data.These features were then input into the BiLSTM to capture temporal dependencies.An attention mechanism was incorporated after SCN and BiLSTM to enhance the extraction of key spatiotemporal features.To address class imbalance,the classification detection model applied EQL v2 to adjust the weights of the minority classes,ensuring that they received equal focus during training.The experimental results indicated that the proposed method outperformed the existing methods in terms of accuracy,FPR,and F1-score and significantly improved the identification rate of minority classes. 展开更多
关键词 Convolutional neural network depthwise separable convolution bidirectional long and short-term memory network class imbalance abnormal traffic detection
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Glucose release kinetics of different feed ingredients and their impact on short-term growth of pigs by influencing carbon-nitrogen supply synchronization
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作者 Mingyi Huang Lei Xue +11 位作者 Yifan Wu Qinzheng Sun Yanwei Xu Jia Li Xiaoyi yu yu cao Jingyi Huang Zeyu Zhang Jinbiao Zhao Dandan Han Defa Li Junjun Wang 《Journal of Animal Science and Biotechnology》 2025年第4期1677-1695,共19页
Background Pigs fed diets with different ingredients but identical nutritional levels show significant differences in growth performance,indicating that growth may also be influenced by the synchronicity of dietary ca... Background Pigs fed diets with different ingredients but identical nutritional levels show significant differences in growth performance,indicating that growth may also be influenced by the synchronicity of dietary carbon and nitrogen supply.Therefore,this study aimed to determine glucose release kinetics of various feed ingredients,to investigate a glucose release pattern that is conducive to synchronized carbon–nitrogen supply,and to elucidate the underlying mechanisms by which this synchronization optimizes growth of pigs.Results We analyzed the glucose release kinetics of 23 feed ingredients in vitro and found that their glucose release rates and amounts varied greatly.Based on this,a nitrogen-free diet and 5 purified diets,which represented the observed variations in glucose release rates and quantities among feed ingredients,were designed for 18 ileal-cannulated pigs.The results demonstrated that slower glucose release pattern could disrupt the synchrony of dietary carbon and nitrogen supply,reducing the growth of pigs and increasing nitrogen losses.Specifically,the diet with slower and moderate amounts of glucose release showed a relatively slower release of amino acids.Pigs fed this diet had the lower amino acid digestibility and the enrichment of harmful bacteria,such as Streptococcus,in the terminal ileum.Conversely,the diets with slower and lower glucose release exhibited a relatively rapid release of amino acids but also resulted in poor growth.They increased glucogenic amino acid digestibility and potentially enriched bacteria involved in nitrogen cycling and carbon metabolism.Notably,only the diet with rapid glucose release achieved synchronized and rapid release of nutrients.Pigs fed this diet exhibited higher amino acid digestibility,decreased harmful bacteria enrichment,improved nutrient utilization,and enhanced short-term growth performance.Conclusions Our research analyzed significant differences in glucose release kinetics among swine feed ingredients and revealed that slow glucose release disrupted dietary carbon–nitrogen supply synchrony,shifting amino acid utilization and enriching pathogens,negatively impacting growth and nutrient utilization.Consequently,choosing feed ingredients releasing glucose at a rapid rate to balance dietary carbon and nitrogen supply helps promote pig growth,and ensures efficient feed utilization. 展开更多
关键词 Energy and nitrogen utilization Glucose release kinetics Growth performance PIG Synchronized nutrient supply
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Multivariate Risk Assessment for Offshore Jacket Platforms by Gaidai Reliability Method
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作者 Oleg Gaidai yu cao +2 位作者 Yan Zhu Fuxi Zhang Hongchen Li 《哈尔滨工程大学学报(英文版)》 2025年第2期428-436,共9页
The novel structural reliability methodology presented in this study is especially well suited for multidimensional structural dynamics that are physically measured or numerically simulated over a representative timel... The novel structural reliability methodology presented in this study is especially well suited for multidimensional structural dynamics that are physically measured or numerically simulated over a representative timelapse.The Gaidai multivariate reliability method is applied to an operational offshore Jacket platform that operates in Bohai Bay.This study demonstrates the feasibility of this method to accurately estimate collapse risks in dynamic systems under in situ environmental stressors.Modern reliability approaches do not cope easily with the high dimensionality of real engineering dynamic systems,as well as nonlinear intercorrelations between various structural components.The Jacket offshore platform is chosen as the case study for this reliability analysis because of the presence of various hotspot stresses that synchronously arise in its structural parts.The authors provide a straightforward,precise method for estimating overall risks of operational failure,damage,or hazard for nonlinear multidimensional dynamic systems.The latter tool is important for offshore engineers during the design stage. 展开更多
关键词 Monte carlo simulation System reliability Jacket offshore structure Bohai bay Energy
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Modulating hole extraction and water oxidation kinetics in CoPi/Au/BiVO_(4) photoanode via strong metal-support interactions
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作者 yu cao Yihan Tian +5 位作者 Bing He Ziyi Qiao Lingyi Li yunhai Zhu Yingkui Yang Xueqin Liu 《Journal of Energy Chemistry》 2025年第10期315-324,共10页
Photoelectrochemical(PEC)water splitting using bismuth vanadate(BiVO_(4))as a photoanode shows promise for renewable hydrogen production.Depositing cobalt phosphate(CoPi)on the BiVO_(4)photoanode as an oxygen evolutio... Photoelectrochemical(PEC)water splitting using bismuth vanadate(BiVO_(4))as a photoanode shows promise for renewable hydrogen production.Depositing cobalt phosphate(CoPi)on the BiVO_(4)photoanode as an oxygen evolution cocatalyst(OEC)is an effective method to improve the PEC performance.However,the CoPi/BiVO_(4)photoanode still faces challenges in terms of slow interface photogenerated carrier transport.Herein,we utilize the advantage of the classical strong metal-support interaction(SMSI)between Au and BiVO_(4)to prepare a CoPi/Au/BiVO_(4)(SMSI-CoPi/Au/BiVO_(4))photoanode.Due to the formation of SMSI,the accumulated electrons at the interface of CoPi/Au induce the accelerated extraction of photogenerated holes.Meanwhile,the active electron density of CoPi is increased,leading to improved water oxidation kinetic.As a result,the SMSI-CoPi/Au/BiVO_(4)photoanode exhibits a high photocurrent density of 5.01 m A cm^(-2)at 1.23 V versus the reversible hydrogen electrode and an applied bias photon-to-current efficiency of 1.78%.This work highlights a novel approach to enhance hole transfer and water oxidation kinetics of OEC/BiVO_(4)composite photoanodes,offering the great potential of using SMSI for PEC water splitting. 展开更多
关键词 Photoelectrochemical water splitting Bismuth vanadate Oxygen evolution cocatalyst Classical strong metal-support interaction Hole extraction
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IMLMA:An Intelligent Algorithm for Model Lifecycle Management with Automated Retraining,Versioning,and Monitoring
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作者 yu cao Yiyun He Chi Zhang 《Journal of Electronic Research and Application》 2025年第5期233-248,共16页
With the rapid adoption of artificial intelligence(AI)in domains such as power,transportation,and finance,the number of machine learning and deep learning models has grown exponentially.However,challenges such as dela... With the rapid adoption of artificial intelligence(AI)in domains such as power,transportation,and finance,the number of machine learning and deep learning models has grown exponentially.However,challenges such as delayed retraining,inconsistent version management,insufficient drift monitoring,and limited data security still hinder efficient and reliable model operations.To address these issues,this paper proposes the Intelligent Model Lifecycle Management Algorithm(IMLMA).The algorithm employs a dual-trigger mechanism based on both data volume thresholds and time intervals to automate retraining,and applies Bayesian optimization for adaptive hyperparameter tuning to improve performance.A multi-metric replacement strategy,incorporating MSE,MAE,and R2,ensures that new models replace existing ones only when performance improvements are guaranteed.A versioning and traceability database supports comparison and visualization,while real-time monitoring with stability analysis enables early warnings of latency and drift.Finally,hash-based integrity checks secure both model files and datasets.Experimental validation in a power metering operation scenario demonstrates that IMLMA reduces model update delays,enhances predictive accuracy and stability,and maintains low latency under high concurrency.This work provides a practical,reusable,and scalable solution for intelligent model lifecycle management,with broad applicability to complex systems such as smart grids. 展开更多
关键词 Model lifecycle management Intelligent algorithms Hyperparameter optimization Versioning and traceability Power metering
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Global performance evaluation of an unstructured mesh ocean-sea ice coupled model(E3SMv2-MPAS)
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作者 Xinyuan Lv Huizan Wang +4 位作者 yu cao Kaijun Ren Yangjun Wang Senliang Bao Hao Ding 《Acta Oceanologica Sinica》 2025年第11期16-33,共18页
This study evaluates the 1995-2020 global ocean-sea ice simulation using the unstructured-mesh model for prediction across scales(MPAS)-ocean/sea ice model within energy exascale earth system model(E3SM)version 2.1(E3... This study evaluates the 1995-2020 global ocean-sea ice simulation using the unstructured-mesh model for prediction across scales(MPAS)-ocean/sea ice model within energy exascale earth system model(E3SM)version 2.1(E3SMv2-MPAS)at 60 km to 10 km resolution.Multi-source observational data are utilized to validate sea surface temperature/salinity,sea ice,three-dimensional thermal-saline structures,mixed layer depth,ocean heat content,and sea surface height.Key results show the following:(1)E3SMv2-MPAS captures seasonal-to-decadal variability in surface fields and sea ice,but shows systematic biases in sea surface temperature of western boundary currents(inadequate eddy parameterization)and Arctic sea surface salinity(misrepresented freshwater fluxes and mixing processes).(2)The model robustly represents three-dimensional climate variability,yet underestimates mixed layer depth in key regions(Antarctic Circumpolar Current and North Atlantic),revealing deficiencies in extreme mixing.(3)Ocean heat content distributions are well-simulated.(4)Sea surface height spatial patterns and interannual variability are accurately reproduced.This work identifies critical refinements for unstructured-mesh models:mesoscale eddy parameterization,polar ocean-sea ice coupling,and multi-scale energy processes,advancing high-resolution climate model development and laying the groundwork for improved ocean forecasting systems. 展开更多
关键词 E3SMv2-MPAS ocean-sea ice coupling eddy-permitting resolution climate model evaluation
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非常规储层微纳米孔隙介质中流体相态研究进展 被引量:9
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作者 汪周华 范琨鹏 +4 位作者 赵建飞 余曹 匡红先 郭平 涂汉敏 《世界石油工业》 2024年第3期68-77,共10页
非常规油气储层具有岩石骨架颗粒小、比表面积大、微纳米孔隙发育的特点,流体与孔隙介质间存在着诸多复杂的界面效应问题,影响微纳米孔隙介质中流体的相态变化规律。对于受限域流体,经典油气相态理论方法忽略分子间相互作用及界面效应... 非常规油气储层具有岩石骨架颗粒小、比表面积大、微纳米孔隙发育的特点,流体与孔隙介质间存在着诸多复杂的界面效应问题,影响微纳米孔隙介质中流体的相态变化规律。对于受限域流体,经典油气相态理论方法忽略分子间相互作用及界面效应的影响,预测微纳米孔隙介质中流体相变特征存在偏差。为了更全面地揭示油气在受限空间中的相态特征及其微观作用机理,总结当前微纳米孔隙介质中流体相态研究技术现状,详细阐述微观实验测试、相态理论模型和分子模拟3种主流技术方法,指出3种技术各自的优缺点,并对未来流体相态研究技术提出展望。分析认为:微观实验测试方法可通过研究流体热力学参数的变化来确定流体相变点,由于实验误差、人为误差等原因,需与理论计算相结合;相态理论模型方法可通过改进临界参数场、考虑流体与孔壁界面作用、考虑相间毛管压力修正相平衡判据方程等方法建立纳米孔隙空间相态理论模型,但是由于没有综合考虑界面效应带来的影响且缺乏有力的实验数据支撑,难以推广应用;分子模拟方法能在分子尺度上揭示流体分子的相行为,但现有研究主要围绕小分子展开,并且与流体发生相变时的临界参数结合得较少。后续研究应以多界面效应耦合影响的微纳米孔隙介质中油气流体相变特征为研究对象,以微观实验、理论模型和分子模拟为技术手段,为描述微纳米孔隙介质中流体相态提供合理的实验测试手段和可靠的理论计算模型。 展开更多
关键词 流体相态 微观实验测试 相态理论模型 分子模拟 油气藏开发
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Discussion on the application prospect of the transient electromagnetic method based on the dual launcher and mine advanced detection
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作者 Zhen Yang Huizhou Liu +5 位作者 Shengqing Wang yu cao Ya Dong Chenghu Niu Weiwen Song Guoxin Xie 《World Journal of Condensed Matter Physics》 CAS 2024年第1期21-33,共13页
The dual transmitter implements the equivalent anti-magnetic flux transient electromagnetic method, which can effectively reduce the scope of the transient electromagnetic detection blind area. However, this method is... The dual transmitter implements the equivalent anti-magnetic flux transient electromagnetic method, which can effectively reduce the scope of the transient electromagnetic detection blind area. However, this method is rarely reported in the detection of pipelines in urban geophysical exploration and the application of coal mines. Based on this, this paper realizes the equivalent anti-magnetic flux transient electromagnetic method based on the dual launcher. The suppression effect of this method on the blind area is analyzed by physical simulation. And the detection experiment of underground pipelines is carried out outdoors. The results show that the dual launcher can significantly reduce the turn-off time, thereby effectively reducing the impact of the blind area on the detection results, and the pipeline detection results verify the device’s effectiveness. Finally, based on the ground experimental results, the application prospect of mine advanced detection is discussed. Compared with other detection fields, the formation of blind areas is mainly caused by the equipment. If the dual launcher can be used to reduce the blind area, the accuracy of advanced detection can be improved more effectively. The above research results are of great significance for improving the detection accuracy of the underground transient electromagnetic method. 展开更多
关键词 A Dual Launcher Physical Simulation Transient Electromagnetic Method Mine Geophysical Prospecting Detection Blind Area Application Prospect
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