检索结果-南通市图书馆

Recent advances of metal vacancies in energy and environmental catalysis:Synthesis,characterization,and roles

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Green Energy & Environment 2025年第1期10卷 84-108页

作者： Long sun Shunzheng Zhao Sirui Gao Ronghui Zhu Yiran Tan Xiaolong Tang Honghong Yi School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing100083China

With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective ***,being one of the hallmarks of modern industry,offers a promising avenue for ***,the question of how to significantly enhance the performance of catalysts has gradually drawn the attention of *** engineering,a commonly employed and effective approach to improve catalyst activity,has become a significant research focus in the catalysis field in recent *** vacancies have received extensive attention due to their simple ***,exploration of metal vacancies has remained stagnant for a considerable period,resulting in a scarcity of comprehensive reviews on this ***,based on the latest research findings,this paper summarizes and consolidates the construction strategies for metal vacancies,characterization techniques,and their roles in typical energy and environmental catalytic ***,it outlines potential challenges in the future,aiming to provide valuable references for researchers interested in investigating metal vacancies.

关键词： Metal vacancies Catalysis Construction strategies Characterization techniques Roles

On construction of strong orthogonal arrays and column-orthogonal strong orthogonal arrays of strength two plus

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Mathematics 2025年

作者： Bochuan Jiang Yaping Wang Fasheng sun School of Mathematics and Statistics Beijing Jiaotong University Key Laboratory of Advanced Theory and Application in Statistics and Data Science Ministry of EducationSchool of Statistics East China Normal University Key Laboratory for Applied Statistics of Ministry of Education and School of Mathematics and Statistics Northeast Normal University

Computer experiments require space-filling designs with good low-dimensional projection *** orthogonal arrays are a type of space-filling design that provides better stratifications in low dimensions than ordinary orthogonal arrays. In this paper, we address the problem of constructing strong orthogonal arrays and column-orthogonal strong orthogonal arrays of strength two plus. Existing methods typically rely on regular designs or specific nonregular designs as base orthogonal arrays, limiting the sizes of the final ***, we propose two general methods that are easy to implement and applicable to a wide range of base orthogonal arrays. These methods produce space-filling designs that can accommodate a large number of factors,provide significant flexibility in terms of run sizes, and possess appealing low-dimensional projection ***, these designs are ideal for computer experiments.

关键词：

A Novel Model for Describing Rail Weld Irregularities and Predicting Wheel-Rail Forces Using a Machine Learning Approach

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2025年第1期142卷 555-577页

作者： linlin sun Zihui Wang Shukun Cui Ziquan Yan Weiping Hu Qingchun Meng State Key Laboratory of High-Speed Railway Track System China Academy of Railway Sciences Corporation LimitedBeijing100081China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed *** can cause significant wheel-rail dynamic interactions,leading to wheel-rail noise,component damage,and *** researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry ***,the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric *** this study,novel theoretical models were developed for three categories of rail weld irregularities,based on measurements of the high-speed railway from Beijing to *** vertical dynamic forces in the time and frequency domains were compared under different running *** forces generated by the rail weld irregularities that were measured and modeled,respectively,were compared to validate the accuracy of the proposed ***,based on the numerical study,the impact force due to rail weld irrregularity is modeled using an Artificial Neural Network(ANN),and the optimum combination of parameters for this model is *** results showed that the proposed model provided a more accurate wheel/rail dynamic evaluation caused by rail weld irregularities than that established in the *** ANN model used in this paper can effectively predict the impact force due to rail weld irrregularity while reducing the computation time.

关键词： Rail weld irregularity high-speed railway vehicle-track coupled dynamics wheel/rail dynamic vertical force artificial neural networks

A Cross Attention Transformer-Mixed Feedback Video Recommendation Algorithm Based on DIEN

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2025年第1期82卷 977-996页

作者： Jianwei Zhang Zhishang Zhao Zengyu Cai Yuan Feng liang Zhu Yahui sun College of Software Engineering Zhengzhou University of Light IndustryZhengzhou450000China Faculty of Information Engineering Xuchang Vocational Technical CollegeXuchang461000China College of Computer Science and Technology Zhengzhou University of Light IndustryZhengzhou450000China College of Electronics and Information Zhengzhou University of Light IndustryZhengzhou450000China

The rapid development of short video platforms poses new challenges for traditional recommendation *** systems typically depend on two types of user behavior feedback to construct user interest profiles:explicit feedback(interactive behavior),which significantly influences users’short-term interests,and implicit feedback(viewing time),which substantially affects their long-term ***,the previous model fails to distinguish between these two feedback methods,leading it to predict only the overall preferences of users based on extensive historical behavior ***,it cannot differentiate between users’long-term and shortterm interests,resulting in low accuracy in describing users’interest states and predicting the evolution of their *** paper introduces a video recommendationmodel calledCAT-MFRec(CrossAttention Transformer-Mixed Feedback Recommendation)designed to differentiate between explicit and implicit user feedback within the DIEN(Deep Interest Evolution Network)*** study emphasizes the separate learning of the two types of behavioral feedback,effectively integrating them through the cross-attention ***,it leverages the long sequence dependence capabilities of Transformer technology to accurately construct user interest profiles and predict the evolution of user *** results indicate that CAT-MF Rec significantly outperforms existing recommendation methods across various performance *** advancement offers new theoretical and practical insights for the development of video recommendations,particularly in addressing complex and dynamic user behavior patterns.

关键词： Video recommendation user interest cross-attention transformer

考虑ESG行为类别的碳减排与经济增长均衡机制研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

经济问题 2025年第1期 15-26页

作者：曲卫华孙娜曲国华山西大学经济与管理学院山西太原030006 山西大学管理与决策研究所山西太原030006 山西财经大学管理科学与工程学院山西太原030006

“双碳”目标视域下,探究企业ESG(Environmental、Social and Governance)行为对碳排放的作用机理具有重要意义。考虑ESG行为存在表面上顺应迎合而实质上“言行不一”,构建了划分ESG行为类别的动态随机一般均衡(DSGE)模型,研究实质性ES... 详细信息

“双碳”目标视域下,探究企业ESG(Environmental、Social and Governance)行为对碳排放的作用机理具有重要意义。考虑ESG行为存在表面上顺应迎合而实质上“言行不一”,构建了划分ESG行为类别的动态随机一般均衡(DSGE)模型,研究实质性ESG行为与策略性ESG行为对碳排放等宏观经济因素的动态传导机制。研究发现:相比难以实现碳减排的策略性ESG行为,企业采取实质性ESG行为能够显著降低碳排放量且对宏观经济有正向影响,推动经济向低碳绿色转型,实现减排与经济发展的“共赢”。企业实质性ESG行为对碳减排与经济增长的影响机制为:(1)内部资本投入机制:企业采取实质性ESG行为对碳减排技术研发投入形成溢出效应,且实质性ESG行为激励企业将生产要素投入由高碳产品转移到低碳产品,以实现“增低碳降高碳”,达到碳减排与经济增长的协调统一;(2)外部政策激励机制:企业采取实质性ESG行为可获得更多的政府碳减排补贴,促使企业增加低碳产出投入,实现外部政策激励与内部低碳转型的协同效应;(3)金融机构信贷优惠机制:企业采取实质性ESG行为能够激发金融机构对其实行差异化信贷优惠利率,增加企业碳减排技术的研发投入,推动绿色金融与绿色技术的协同发展。研究为辨识ESG行为类别推动企业低碳转型发展提供理论依据与政策启示。

关键词：实质性ESG行为策略性ESG行为绿色金融碳排放动态随机一般均衡模型

维普期刊数据库

Molecular dynamics simulation of quartz deformation under slow earthquake background

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2025年

作者： Jingxian sun Qianqian GUO Quanlin HOU College of Earth and Planetary Sciences University of Chinese Academy of Sciences Key Laboratory of Computational Geodynamics CAS

Slow earthquakes are the primary mechanism of slow energy release, and research on the focal mechanism has been inconclusive. Studies have primarily focused on the friction law based on physical mechanisms and have suggested that slow earthquakes are caused by brittle faults. However, the focal strength and structural characteristics of slow earthquakes in subduction zones provide evidence of plastic deformation. What is the role of plastic deformation in the focal mechanisms of slow earthquakes? Mechanochemical study have shown that mechanical forces can directly affect chemical bonds. In this study,we examine the storage and release of chemical energy during plastic deformation and consider a mechanochemical process in the focal mechanism of slow earthquakes. Combined with the Tersoff potential, molecular dynamics simulation on the shear deformation process of two α-quartz crystals show that the shear modulus of α-quartz is 18 GPa, and that the crystal model primarily exhibits atoms flowing and changing in the direction of chemical bonds during the steady-state flow stage. The molecular potential energy and stress vary in an oscillating up-and-down curve during shear, indicating that chemical energy can be stored and released during plastic deformation. This is consistent with the energy variation during slow earthquakes. Under the initial simple-shear loading condition, α-quartz crystals undergo general shear deformation instead of plane strain and the angle between the longest instantaneous stretching axis （ISA1） and the shearing direction is approximately 30°, not 45°. Both the deformation type and direction of ISA1are contrary to basic deformation theory, which may provide clues for future *** study reveals the process of quartz elastic-plastic shear deformation on an atomic scale. This information is useful for understanding focal mechanisms of slow earthquakes. This study is part of a series of investigations on tectonic stress chemistry.

关键词：

The Insect Oviposition Firstly Discovered on the Middle Jurassic Ginkgoales Leaf from Inner Mongolia, China

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2014年第1期88卷 18-28页

作者： na Yuling sun Chunlin li Tao li Yunfeng The Key Laboratory for Evolution of Past life and Environment in Northeast Asia Ministry of Education Jilin University Research Center of Palaeontology & Stratigraphy Jilin University

Although the evidence of insect oviposition on plant organs has been reported from the late Paleozoic to the Miocene, record from the middle Jurassic is still blank. This paper reports a significant evidence of insect oviposition on plant leaf from the middle Jurassic for the first time. The ovipositional scar is distributed on the abaxial surface of Sphenobaiera leaf（Ginkgoales） from the middle Jurassic Daohugou Formation of Inner Mongolia, China. A new ichnospecies Paleoovoidus venustus sp. nov. is described. The scar is elliptic to oval, arranged in longitudinal rows between leaf veins with almost regular distance, with its long axis paralleling to the leaf venation. This discovery adds new information to the morphology of insect endophytic oviposition probably produced by Odonata existed in a terrestrial ecosystem ~165 Ma ago. The new materials also provide important data for the study of insect reproductive biology, plant-insect interaction and coevolution, as well as understanding the paleoclimate and palaeoenvironment during that time in northeast China.

关键词： Fossil insect egg Oviposition Paleoovoidus Ginkgoales Middle Jurassic China

维普期刊数据库

Investigations of liquid-liquid transitions in metallic melts by fast differential scanning calorimetry

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2025年

作者： Qi Cheng Yonghao sun Weihua Wang Beijing national Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University School of Physics and Electronic Information Anhui Normal University Institute of Physics Chinese Academy of Sciences Songshan Lake Materials Lab

liquid-liquid transition in metallic melts is an intriguing phenomenon often confused with liquid-liquid separation, oxidation or precipitation. Here, we employ a state-of-the-art ultrafast chip-based differential scanning calorimeter to investigate the thermal behavior of six metallic melts, ranging from unary to quinary systems, at temperatures above their liquidus. Calorimetric signals of liquid-liquid transition vary across systems: Sn melts showed no direct endothermic or exothermic events, though liquid-liquid transition influenced solidification and melting temperatures, while Yb-Zn melts exhibited an exothermic peak during cooling,indicating liquid-liquid transition. Thermal signals in other systems including li, Pd-Ni-P, Yb-Mg-Zn-Cu and Au-Ag-Pd-Cu-Si,are primarily driven by compositional changes. Our in-situ analysis provides new insights into the structural and compositional evolution of metallic melts, offering significant implications for the design and processing of novel materials.

关键词：

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

儿童植入式静脉输液港并发症危险因素

中华灾害救援医学 2017年第1期5卷 41-44页

作者：李胜男安丽娜张谦孙玲李玮朱静肖博武警总医院麻醉手术科北京100039 武警总医院胸外科北京100039

目的探讨植入式静脉输液港(implantable venous access port,IVAP)常见并发症产生的危险因素,为制定更有效更有针对性的护理方法提供依据。方法回顾性研究武警某三甲医院429例IVAP患儿的临床资料,用SPSS 19.0软件包对可能与并发症有关... 详细信息

目的探讨植入式静脉输液港(implantable venous access port,IVAP)常见并发症产生的危险因素,为制定更有效更有针对性的护理方法提供依据。方法回顾性研究武警某三甲医院429例IVAP患儿的临床资料,用SPSS 19.0软件包对可能与并发症有关的危险因素进行分析。结果 429例IVPA患儿发生并发症32例,发生率为7.46%,其中,术后1周内发生并发症11例(2.56%);术后1周后发生并发症21例(4.90%)。单因素分析结果显示:肿瘤分型(χ2=12.786,P<0.05)、血白蛋白水平(χ2=6.334,P=0.012)与输液港置管患儿并发症发生相关。多因素logistic回归分析结果显示,肿瘤分型与血白蛋白水平两个危险因素相互独立(P<0.05),肿瘤类型与并发症的[相对危险度(odds ratio,OR),95%置信区间(confidence interval,CI)]=3.720(1.774~7.086),血白蛋白水平与并发症的OR(95%CI)=2.672(1.259~5.673)。结论血液系统肿瘤和血白蛋白减低,可能是植入式静脉输液港发生并发症的危险因素。

关键词：植入式静脉输液港并发症儿童

维普期刊数据库