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Elastic three-dimensional phononic topological insulators with Dirac hierarchy

Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 54-62页

作者： shao-Yong Huo Qiu-Shuang Yang Jiu-Jiu Chen Hong-Kang li Long-Chao Yao fu-Chun He Chun-Ming fu College of Mechanical Engineering University of South ChinaHengyang 421001China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

Three-dimensional(3D)phononic topological insulators(TIs)featuring two-dimensional(2D)surface states and one-dimensional(1D)hinge states have opened up a new route for multi-dimensional robust wave transport,providing unprecedented methods for integrated acoustic sensors and energy harvesting ***,aiming at the elastic 3D phononic TI with gapless surface states and hinge states,the realization of elastic 3D phononic TIs with gapless surface states and hinge states is a significant challenge due to the complicated multi-mode polarization of elastic waves in 3D *** this study,we demonstrate an elastic 3D phononic TI with a Dirac hierarchy by elaborately operating the corresponding spatial symmetries of the chiral honeycomb ***,a 3D double Dirac cone of elastic wave can be achieved by doubling the lattice along the outof-plane direction to fold two iso-frequency Weyl *** topological phase transitions and 2D gapless two-fold Dirac surface states of elastic wave are realized by breaking the half-lattice spatial translation ***,based on the Brillouin zone folding along the in-plane direction,the 2D gapless two-fold surface Dirac cones are folded into four-fold surface Dirac ***,by inducing the relative radius of adjacent holes to break the in-plane spatial inversion symmetry,the fourfold surface Dirac cones are gapped and associated with a surface state inversion,in which the gapless 1D hinge Dirac dispersion is *** research offers a route for engineering the hierarchies of TIs in 3D elastic wave systems and provides new possibilities for designing 3D ultrasonic devices with unconventional functions.

关键词： Dirac topological hierarchy

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Elastoplastic cup model for cement-based materials

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Water Science and Engineering 2010年第1期3卷 102-112页

作者： Yan ZHANG Jian-fu shao College of Mechanics and Materials Hohai University Nanjing 210098 P. R. China Laboratory of Mechanics of lille UMR 8107 CNRS Villeneuve d＇Ascq 59655 France

Based on experimental data obtained from triaxial tests and a hydrostatic test, a cup model was formulated. Two plastic mechanisms, respectively a deviatoric shearing and a pore collapse, are taken into account. This model also considers the influence of confining pressure. In this paper, the calibration of the model is detailed and numerical simulations of the main mechanical behavior of cement paste over a large range of stress are described, showing good agreement with experimental results. The ease study shows that this cup model has extensive applicability for cement-based materials and other quasi-brittle and high-porosity materials in a complex stress state.

关键词： cup model cement-based materials plastic shearing mechanism plastic porecollapse mechanism numerical simulation

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Efficient light-driven reductive amination of furfural to furfurylamine over ruthenium-cluster catalyst

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Journal of Energy Chemistry 2023年第1期76卷 239-248,I0007页

作者： Zhen Xue Shasha Wu Yujing fu Lan Luo Min li Zhenhua li Mingfei shao lirong Zheng Ming Xu Haohong Duan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Department of Chemistry TsinghuaUniversityBeijing 10084China Institute of High Energy Physics The Chinese Academy of SciencesBeijing 100049China

Selective reductive amination of carbonyl compounds with high activity is very essential for the chemical and pharmaceutical industry,but scarcely successful paradigm was reported via efficient photocatalytic ***,the ultrasmall Ru nanoclusters(~0.9 nm)were successfully fabricated over P25 support with positive charged Ru^(δ+)species at the interface.A new route was developed to achieve the furfural(FAL)to furfurylamine(FAM)by coupling the light-driven reductive amination and hydrogen transfer of ethanol over this type ***,the photocatalytic activity and selectivity are strongly dependent on the particle size and electronic structure of *** Ru^(δ+)species at the interface promote the formation of active imine intermediates;moreover,the Ru nanoclusters facilitate the separation efficiency of electrons and holes as well as accelerate the further hydrogenation of imine intermediates to product primary *** contrast Ru particles in larger nanometer size facilitate the formation of the furfuryl alcohol and excessive hydrogenation *** addition,the coupling byproducts can be effectively inhibited via the construction of *** study offers a new path to produce the primary amines from biomass-derived carbonyl compounds over hybrid semiconductor/metal-clusters photocatalyst via light-driven tandem catalytic process.

关键词： furfural Reductive amination Ru nanoclusters Hydrogen transfer Photocatalysis

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Copper-cobalt-nickel oxide nanowire arrays on copper foams as self-standing anode materials for lithium ion batteries

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Chinese Chemical Letters 2021年第2期32卷 938-942页

作者： Xiaomin Kang Guodong fu Xuewan Wang lin shao Weili li Chi-Wing Tsang Xiao-Ying Lu Xian-Zhu fu Jing-li Luo Shenzhen Key Laboratory of Polymer Science and Technology Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and Engineering.Shenzhen UniversityShenzhen 518060China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province.College of Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Faculty of Science and Technology Technological and Higher Education Institute of Hong KongHong KongChina Department of Chemical and Materials Engineering University of AlbertaEdmontonAlbertaT6C 1H9Canada

Numerous scientists are in the pursuit of energy storage materials with high energy and high power density by assembly of electrochemically active materials into conductive scaffolds,owing to the emerging need for next-generation energy storage *** this architectures,the active materials bonded to the conductive scaffold can provide a robust and free-standing structure,which is crucial to the fabrication of materials with high gravimetric ***,hierarchical copper-cobalt-nickel ternary oxide(CuCoNi-oxide) nanowire arrays grown from copper foam were successfully fabricated as freestanding anode materials for lithium ion batteries(liBs).CuCoNi-oxide nanowire arrays could provide more active sites owing to the hyperbranched structure,leading to a better specific capacity of 1191 mAh/g,cycle performance of 73% retention in comparison to CuO nanowire structure,which exhibited a specific capacity of 1029 mAh/g and capacity retention of 43%,respectively.

关键词： Binder-free electrode Cuo array Copper-cobalt-nickel oxide(CuCoNi-oxide) Volumetric Effect lithium ion batteries

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Ti/(Ti,Cr)N/CrN multilayer coated 316L stainless steel by arc ion plating as bipolar plates for proton exchange membrane fuel cells

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Journal of Energy Chemistry 2017年第1期26卷 168-174页

作者： Shengli Wang Ming Hou Qing Zhao Yongyi Jiang Zhen Wang Huizhe li Yu fu Zhigang shao fuel Cell System and Engineering Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Dalian Sunrise Power Co. LTD

Arc ion plating (AIP) is applied to form Ti/(Ti,Cr)N/CrN multilayer coating on the surface of 316L stainless steel (SS316L) as bipolar plates for proton exchange membrane fuel cells (PEMFCs). The characterizations of the coating are analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Interfacial contact resistance (ICR) between the coated sample and carbon paper is 4.9 m Omega cm(2) under 150 N/cm(2), which is much lower than that of the SS316L substrate. Potentiodynamic and potentiostatic tests are performed in the simulated PEMFC working conditions to investigate the corrosion behaviors of the coated sample. Superior anticorrosion performance is observed for the coated sample, whose corrosion current density is 0.12 mu A/cm(2). Surface morphology results after corrosion tests indicate that the substrate is well protected by the multilayer coating. Performances of the single cell with the multilayer coated SS316L bipolar plate are improved significantly compared with that of the cell with the uncoated SS316L bipolar plate, presenting a great potential for PEMFC application. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

关键词： Stainless steel bipolar plate Proton exchange membrane fuel cell Arc ion plating Multilayer coating

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Elevated-temperature tribological behavior of Ti–B–C–N coatings deposited by reactive magnetron sputtering

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Rare Metals 2015年第12期34卷 838-843页

作者： Xiang-Yang Chen shao-fu Huang Sheng-li Ma Run Huang Jin Zhang Hai-Xia Hu School of Mechanical Engineering Anhui University of Science and Technology State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University School of Materials Science and Engineering Anhui University of Science and Technology

Quaternary Ti–B–C–N coatings with various carbon contents were deposited on high-speed steel (HSS) substrates by reactive magnetron sputtering (RMS) system. The elevated-temperature tribological behavior of Ti–B–C–N coatings was explored using pin-on-disk tribometer, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The present results show that the steady-state friction coefficient value and the instantaneous friction coefficient fluctuation range of Ti–B–C–N coatings decrease as carbon content increases at 100 and 300°C, while the steady-state friction coefficient value of all Ti–B–C–N coatings becomes higher than 0.4 at 500°C. As ambient temperature increases, the running-in periods of all Ti–B–C–N coatings become shorter. Wear damage to Ti–B–C–N coatings during sliding at elevated temperature is mainly caused by adhesive wear, and adhesive-wear damage to Ti–B–C–N coatings increases as ambient temperature increases; however, higher carbon content is beneficial for decreasing the adhesive-wear damage to Ti–B–C–N coatings during sliding at elevated temperature.

关键词： Tribological behavior Ti–B–C–N coatings Reactive magnetron sputtering Elevated temperature

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Inflammatory bowel disease unclassified

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第4期12卷 280-286页

作者： Ning ZHOU Wei-xing CHEN shao-hua CHEN Cheng-fu XU You-ming li Department of Gastroenterology the First Affiliated Hospital College of Medicine Zhejiang University Hangzhou 310003 China

Objective:Inflammatory bowel diseases (IBDs) are idiopathic,chronic,and inflammatory intestinal *** two main types,ulcerative colitis (UC) and Crohn's disease (CD),sometimes mimic each other and are not readily *** purpose of this study was to present a series of hospitalized cases,which could not initially be classified as a subtype of IBD,and to try to note roles of the terms indeterminate colitis (IC) and inflammatory bowel disease unclassified (IBDU) when such a dilemma ***:Medical records of 477 patients hospitalized due to IBD,during the period of January 2002 to April 2009,were retrospectively studied in the present *** available previous biopsies from endoscopies of these patients were ***:Twenty-seven of 477 IBD patients (5.7%) had been initially diagnosed as having *** them,23 received colonoscopy and histological examinations in our hospital.A total of 90% (9/10) and 66.7% (4/6) of patients,respectively,had a positive finding via wireless capsule endoscopy (CE) and double-balloon enteroscopy (DBE).The barium-swallow or small bowel follow-through (SBFT) was performed on 11 *** changes were observed under computer tomographic (CT) scanning in 89.5% (17/19) of *** treatment strategies were employed for all ***:Our data indicate that IBDU accounts for 5.7% of initial diagnoses of *** definition of IBDU is valuable in clinical *** those who had no clear clinical,endoscopic,histological,or other features affording a diagnosis of either UC or CD,IBDU could be used parenthetically.

关键词： Inflammatory bowel disease unclassified Ulcerative colitis Crohn’s disease Subtype Diagnosis

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Characteristics of Climate Change in the Lake Basin Area of Gangcha County

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Computers, Materials & Continua 2022年第10期73卷 363-379页

作者： Wenzheng Yu Aodi fu li shao Haitao liu Xin Yao Tianliang Chen Hanxiaoya Zhang School of Geographical Sciences Nanjing University of Information Science&TechnologyNanjing210044China School of Environmental Science&Engineering Nanjing University of Information Science&TechnologyNanjing210044China Faculty of Science The University of Auckland1010New Zealand

This paper mainly was based on the average temperature,precipitation,humidity,and wind direction of Gangcha county from 1960 to *** using wavelet analysis and Mann-Kendall(M-K)mutation analysis,specifically analyzed the climate change characteristics in the lake basin area of Gangcha *** result showed that the climatic change in the lake basin area of Gangcha county is *** average temperature,average minimum temperature,average maximum temperature,and evaporation showed an increasing *** the evaporation in the study area was higher than *** average relative humidity showed a decreasing *** the sunshine and the average wind speed percentage showed a significant decreasing *** the Morelet wavelet,The time series of annual mean temperature,annual evaporation and annual sunshine percentage all have quasi3a and quasi4A periods,and the annual mean precipitation has quasi2–3A,quasi2–5A and quasi2–6A periods,which appear in 1996–2005,1962–1978 and 1978–1996 *** mean annual relative humidity has obvious quasi2–7A and quasi3A time series,which appear from 1960 to 1996,1997 to 2005 and after 2008,*** annual mean wind speed has quasi3–4A and quasi5A time series characteristics,which appear in 1964–1967,1984–1995,after 2009 and 1971–1983,*** Mann-Kendall(M-K)mutation analysis,it is found that the mutations of evaporation and the average speed of wind are *** mutation of evaporation started in 2004,and the mutation of average started in 2003.

关键词： Climate change the qinghai lake Morelet wavelet Mann-Kendall test

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内皮祖细胞与间充质干细胞治疗血管支架相关疾病

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中国组织工程研究 2025年第19期29卷 4091-4101页

作者：李清音李林华张春乐付平四川大学华西医院肾脏内科肾脏病研究所四川省成都市610041 四川大学疾病分子网络前沿科学中心四川省成都市610041

背景:随着干细胞研究的发展,成体干细胞如内皮祖细胞和间充质干细胞在动脉粥样硬化、血管支架植入损伤并发症中的治疗效能逐渐被发现,由于静脉输注成体干细胞治疗疾病存在靶向性差、治疗效率低等问题,近年来对血管支架表面改性以实现内... 详细信息

背景:随着干细胞研究的发展,成体干细胞如内皮祖细胞和间充质干细胞在动脉粥样硬化、血管支架植入损伤并发症中的治疗效能逐渐被发现,由于静脉输注成体干细胞治疗疾病存在靶向性差、治疗效率低等问题,近年来对血管支架表面改性以实现内皮祖细胞或间充质干细胞的局部聚集与功能调节一直是研究的焦点。目的:论述内皮祖细胞、间充质干细胞在血管支架相关疾病中的治疗进展,以及基于内皮祖细胞、间充质干细胞的血管支架设计方面的研究现状。方法:在CNKI、万方、PubMed、Web of Science数据库检索建库以来发表的相关文献。中文检索词“内皮损伤,支架植入术,血栓,内膜增生,动脉粥样硬化,内皮修复,内皮祖细胞,间充质干细胞,血管支架”;英文检索词“endothelial injury,stenting,thrombosis,intimal hyperplasia,atherosclerosis,endothelial repair,endothelial regeneration,endothelial progenitor cell,mesenchymal stem cell,vascular stent,vascular scaffold”。根据纳入和排除标准,最终对127篇文献进行综述。结果与结论:内皮祖细胞、间充质干细胞能够通过分化以及旁分泌作用治疗动脉粥样硬化及支架植入损伤并发症,其作用机制主要包括保护内皮细胞、调节炎症细胞与炎症因子表达、调节平滑肌细胞增殖和表型等。间充质干细胞在治疗应用中可能伴有血栓、血管钙化等不良反应,使用细胞外囊泡、联合使用肝素进行表面设计是解决这一问题的可行方案。目前基于内皮祖细胞的支架研究较多,主要从内皮祖细胞的募集、捕获、增殖、分化与活性等方面进行支架表面改性;血管领域基于间充质干细胞捕获的支架研究较少,但间充质干细胞来源外泌体洗脱支架被发现具有极高的治疗效能。此外一些基础疾病如糖尿病可能会对成体干细胞活性造成影响,导致基于干细胞设计的支架失去效能,因而未来在设计相应的支架时,应注意考虑这方面的影响因素。

关键词：内皮祖细胞间充质干细胞动脉粥样硬化球囊损伤支架植入损伤内膜增生表面改性

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Enantioseparation of Racemic Naproxen Esters on Cellulose Tris (4-methylbenzoate) Chiral Stationary Phase

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Chinese Chemical Letters 2002年第2期13卷 151-152页

作者： Bao Hai shao Xiu Zhu XU li ZOU Xiao Yun fu Department of Chemistry Zhejiang UniversityHangzhou 310027

Several kinds of racemic naproxen ester were successfully separated on CTMB chiral stationary phase with hexane-ethanol (98:2, vol./vol.) as the mobile phase. The influence of mobile phase composition and structure of racemic naproxen ester on chiral separation was studied and the chiral recognition mechanism of CTMB was discussed.

关键词： Cellulose tris (4-methylbenzoate) naproxen chiral stationary phase enantioseparation.

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