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Evolutionary history shapes variation of wood density of tree species across the world

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Plant Diversity 2024年第3期46卷 283-293页

作者： Fangbing Li Hong Qian Jordi Sardans Dzhamal y.Amishev Zixuan Wang Changyue zhang Tonggui Wu xiaoniu xu xiao Tao xingzhao Huang Anhui Province Key Laboratory of Forest Resources and Silviculture Anhui Agricultural UniversityHefei 230036China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA CREAF Cerdanyola del VallesBarcelona 08193Spain Global Ecology Unit CREAF-CSIC-UAB CSICBellaterraBarcelona 08193Spain Key Laboratory of Ecosystem Carbon Source and Sink China Meteorological Administration(ECSS-CMA)School of Applied MeteorologyNanjing University of Information Science&Technology219 Ningliu RoadNanjing 210044China Department of natural Resources Management Lakehead UniversityThunder BayOntario P7B 5E1Canada School of Forestry&Landscape of Architecture Anhui Agricultural UniversityHefei 230036China Research Institute of Subtropical Forestry Chinese Academy of ForestryHangzhou 311400China

The effect of evolutionary history on wood density variation may play an important role in shaping variation in wood density,but this has largely not been *** a comprehensive global dataset including 27,297 measurements of wood density from 2621 tree species worldwide,we test the hypothesis that the legacy of evolutionary history plays an important role in driving the variation of wood density among tree *** assessed phylogenetic signal in different taxonomic(e.g.,angiosperms and gymnosperms)and ecological(e.g.,tropical,temperate,and boreal)groups of tree species,explored the biogeographical and phylogenetic patterns of wood density,and quantified the relative importance of current environmental factors(e.g.,climatic and soil variables)and evolutionary history(i.e.,phylogenetic relatedness among species and lineages)in driving global wood density *** found that wood density displayed a significant phylogenetic *** density differed among different biomes and climatic zones,with higher mean values of wood density in relatively drier regions(highest in subtropical desert).Our study revealed that at a global scale,for angiosperms and gymnosperms combined,phylogeny and species(representing the variance explained by taxonomy and not direct explained by long-term evolution process)explained 84.3%and 7.7%of total wood density variation,respectively,whereas current environment explained 2.7%of total wood density variation when phylogeny and species were taken into *** angiosperms and gymnosperms were considered separately,the three proportions of explained variation are,respectively,84.2%,7.5%and 6.7%for angiosperms,and 45.7%,21.3%and 18.6%for *** study shows that evolutionary history outpaced current environmental factors in shaping global variation in wood density.

关键词： Wood density Phylogeny Angiosperms Gymnosperms Climate factors Biophysical parameters

Recent innovations in laser additive manufacturing of titanium alloys

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International Journal of Extreme Manufacturing 2024年第3期6卷 2-37页

作者： Jinlong Su Fulin Jiang Jie Teng Lequn Chen Ming yan Guillermo Requena Lai-Chang zhang y Morris Wang Ilya V Okulov Hongmei Zhu Chaolin Tan College of Materials Science and Engineering Hunan UniversityChangsha 410082People’s Republic of China Singapore Institute of Manufacturing Technology(SIM Tech) Agency for ScienceTechnology and Research(A∗STAR)5 Cleantech LoopSingapore 636732Singapore Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China Institute of Materials Research German Aerospace Center(DLR)Linder Höhe51147 CologneGermany Centre for Advanced Materials and Manufacturing Edith Cowan University270 Joondalup DriveJoondalupPerthWestern Australia 6027Australia Department of Materials Science and Engineering University of CaliforniaLos AngelesCA 900095United States of America Leibniz Institute for Materials Engineering-IWT Badgasteiner Str.328359 BremenGermany Faculty of Production Engineering University of BremenBadgasteiner Str.128359 BremenGermany Key Laboratory of Hunan Province of Equipment Safety Service Technology under Extreme Environment University of South ChinaHengyangPeople’s Republic of China RWTH Aachen University Metallic Structures and Materials Systems for Aerospace EngineeringD-52062 AachenGermany

Titanium(Ti)alloys are widely used in high-tech fields like aerospace and biomedical *** additive manufacturing(LAM),as an innovative technology,is the key driver for the development of Ti *** the significant advancements in LAM of Ti alloys,there remain challenges that need further research and development *** recap the potential of LAM high-performance Ti alloy,this article systematically reviews LAM Ti alloys with up-to-date information on process,materials,and *** feasible solutions to advance LAM Ti alloys are reviewed,including intelligent process parameters optimization,LAM process innovation with auxiliary fields and novel Ti alloys customization for *** auxiliary energy fields(***,acoustic,mechanical deformation and magnetic fields)can affect the melt pool dynamics and solidification behaviour during LAM of Ti alloys,altering microstructures and mechanical *** kinds of novel Ti alloys customized for LAM,like peritecticα-Ti,eutectoid(α+β)-Ti,hybrid(α+β)-Ti,isomorphousβ-Ti and eutecticβ-Ti alloys are reviewed in ***,machine learning in accelerating the LAM process optimization and new materials development is also *** review summarizes the material properties and performance envelops and benchmarks the research achievements in LAM of Ti *** addition,the perspectives and further trends in LAM of Ti alloys are also highlighted.

关键词： additive manufacturing titanium alloys auxiliary field machine learning aerospace materials lightweight materials novel alloys

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： Qing-Ping Li Jin-ya zhang Jia-xiang zhang yong-xue zhang CnOOC Research Institute Company Limited Beijing100028China State Key Laboratory of natural Gas Hydrate Beijing100028China College of Mechanical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump *** mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response characteristics

Solid Bronsted acidity boosts adsorption reactivity of nano-adsorbent for water decontamination

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 23-34页

作者： Sikai Cheng Zhixian Li Kaisheng zhang Qingrui zhang xiaolin zhang Bingcai Pan State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China Environmental Materials and Pollution Control Laboratory Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Hebei Key Laboratory of Heavy Metal Deep-remediation in Water and Resource Reused Qinhuangdao 066004China Research Center for Environmental nanotechnology(ReCEnT) Nanjing UniversityNanjing 210023China

Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through innersphere coordination,strong competition for hydroxyl ions still hinders efficient water *** addition,the critical issue of polysilicate scaling that results from the ubiquitous silicates must be *** tackle these issues,an alternative approach to enhancing adsorption reactivity by modifying nano-adsorbents with dual Lewis and Bronsted acidity is *** feasibility of this approach is demonstrated by growing zirconium phosphate(ZrP)inside a gel-type anion exchanger,n201,to produce nanocomposite ZrP@n201,in which the confined ZrP contained an otherwise metastable amorphous phase with Lewis acidic Zr^(4+) sites and Bronsted acidic monohydrogen phosphate groups(-O_(3)POH).Compared with the Lewis acidic nano-zirconium oxide analog(HZ0@n201),ZrP@n201 exhibited a greatly improved adsorption capacity(117.9 vs.52.3 mg/g-Zr)and mass transfer rate(3.56×10^(-6) vs.4.55×10^(-7) cm/s),while bulk ZrP produced a thermodynamically stableα-phase with Bronsted acidity that exhibited negligible adsorption capability toward *** enhanced defluoridation activity of ZrP@n201 is attributed to Bronsted acidity and the increased outer electron density of ZA+sites,as corroborated using xPS and solid-state nMR ***,Bronsted acidity strengthens the resistance of ZrP@n201 to silicate,allowing its full regeneration during cyclic *** tests demonstrated 3-10 times the amount of clean water from(waste)for ZrP@n201 as compared to both HZO@n201 and the widely used activated aluminum *** study highlights the potential of developing nano-adsorbents with dual acidities for various environmental remediation applications.

关键词： nanocomposite Selective adsorption Fluoride removal Dual Lewis and Bronsted acidity Regeneration

A Bionic Starfish Adsorption Crawling Soft Robot

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Journal of Bionic Engineering 2024年第1期21卷 149-165页

作者： xiangang Huang Chenghao zhang Wenqi Feng xiangye zhang Deyuan zhang yanqiang Liu Institute of Bionic and Micro-nano Systems School of Mechanical Engineering and AutomationBeihang UniversityBeijing 100191China

A variety of soft wall-climbing robots have been developed that can move in certain *** of these soft robots can only move on conventional surfaces and lack adaptability to complex *** the adaptability of soft robots on complex surfaces is still a challenging *** this end,we study the layered structure of the starfish tube foot and the valve flap structure in the water vascular system,and use an ultrasonic stress detector to study the stiffness distribution of the arm *** by the motion of the starfish,we present a bionic soft wall-climbing robot,which is driven by two groups of pneumatic feet and achieves body bending through active adaptation *** design the structure of the foot to flex to provide driving force,and there are suction cups at the end of the foot to provide *** soft foot has a simple structure design,adapts to a variety of surfaces,and does not damage the surface of the *** stiffness layers achieve stiffness changes by the principle of line *** Central Pattern Generator theory is introduced to coordinately control the multiple feet of the *** experiments,we verify the adaptability of the soft robot to curved *** research may provide a reference for the design and development of crawling soft robots on complex surfaces.

关键词： Starfish Tube foot Biomimetic robot Soft robot Climbing robot

Flexible regulation engineering of titanium nitride nanofibrous membranes for efficient electromagnetic microwave absorption in wide temperature spectrum

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nano Research 2024年第3期17卷 1666-1675页

作者： Cuiping Li Lu zhang Shuai zhang Qiqi yu Dan Li Lei zhang Chunhong Gong Jingwei zhang Institute of Functional Polymer Composites College of Chemistry and Molecular SciencesHenan UniversityKaifeng 475004China national&Local Joint Engineering Research Center for Applied Technology of Hybrid nanomaterials Henan UniversityKaifeng 475004China

Simultaneous development of well impedance matching and strong loss capability has become a mainstream method for achieving outstanding electromagnetic microwave absorption(EMWA)performances over wide temperature ***,it is difficult to pursue both due to the mutual restraint of relationship between impedance matching and loss capability about ***,we propose a flexible regulation engineering of titanium nitride(Tin)nanofibrous membranes(nMs,TnMs),which could be distributed uniformly in the polydimethylsiloxane(PDMS)matrix and contributed to the formation of abundant local conductive networks,generating the local conductive loss and enhancing the loss ability of ***,when the TnMs are used as functional units and dispersed in the matrix,the corresponding composites exhibit an outstanding anti-reflection effect on *** hoped,under the precondition of good impedance matching,local conductive loss and polarization loss together improve the loss capacity at room temperature,and polarization loss can compensate the local conductive loss to acquire effective dielectric response at elevated *** from the reasonably synergistic loss ability caused by flexible regulation engineering,the corresponding composites exhibit the perfect EMWA performances in a wide temperature range from 298 to 573 *** work not only elaborates the ponderable insights of independent membrane in the composition-structure-function connection,but also provides a feasible tactic for resolving coexistence of well impedance matching and strong loss capability issues in wide temperature spectrum.

关键词： flexible titanium nitride nanofibrous membranes local conductive loss dielectric loss electromagnetic microwave absorption wide temperature spectrum

Synthetic fungal melanin UV absorbers

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Science China Chemistry 2024年第9期67卷 3098-3110页

作者： Chao Wang Rong zhang Jianhua zhang xueqian zhang Hengjie zhang Huan Cao Zhen yang yiwen Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Department of Radiology Huaxi MR Research CenterFunctional and Molecular Imaging Key Laboratory of Sichuan ProvinceNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengdu 610041China

Agents with robust ultraviolet(UV)absorption capabilities play a vital role in safeguarding organisms and inorganic materials from UV ***,the synthetic procedures towards these UV absorbers are usually lengthy and complicated,accompanied by undesirable side reactions and the generation of toxic *** nature,allomelanin,a class of melanins variant found in melanized fungi near the Chernobyl nuclear power plant,plays crucial roles in the cell wall of melanized fungi,offering resistance to harsh external environments and promising UV resistance ***,allomelanin can be rapidly biosynthesized via the polymerization of 1,8-dihydroxynaphthalene in presence of enzymes in *** by this,we report here a green enzymatic polymerization strategy to efficiently and eco-friendly synthesize polydihydroxynaphthalene(PDHn)-based artificial allomelanin nanoparticles(nPs)with interesting *** calculations and experimental results demonstrated that the PDHn nPs exhibited excellent UVabsorption capacity,surpassing another widely used artificial melanin,polydopamine(PDA).Moreover,the light absorption mechanism of PDHn nPs was systematically elucidated for the first ***,the PDHn nPs were incorporated with polyvinyl alcohol(PVA)to create an anti-aging composite film with significantly enhanced UV shielding *** potential of these composite films in safeguarding plants from UV damage was meticulously ***,these PDHn nPs were first found to produce hydroxyl radicals(·OH)under UV irradiation,offering antibacterial properties that expand their potential applications.

关键词： melanin artificial allomelanin nanoparticles green synthesis UV absorption antibacterial

Chiral transmission by an open evolution trajectory in a non-Hermitian system

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Light(Science & Applications) 2024年第4期13卷 628-636页

作者： xiaoqian Shu Qi Zhong Kai Hong Oubo you Jian Wang Guangwei Hu Andrea Alù Shuang zhang Demetrios n.Christodoulides Lin Chen Wuhan national Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China. Zhejiang Lab Hangzhou 311121China. CREOL College of Optics and PhotonicsUniversity of Central FloridaOrlandoFlorida 32816USA. Department of Physics The University of Hong KongHong KongChina. School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore. Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY 10031USA. Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen 518063China

Exceptional points(EPs),at which two or more eigenvalues and eigenstates of a resonant system coalesce,are associated with non-Hermitian Hamiltonians with gain and/or loss *** encircling of EPs has received significant interest in recent years,as it has been shown to lead to highly nontrivial phenomena,such as chiral transmission in which the final state of the system depends on the encircling ***,chiral transmission for a pair of eigenmodes has been realized by establishing a closed dynamical trajectory in parity-time-(PT-)or anti-PT-symmetric *** chiral transmission of symmetry-broken modes,more accessible in practical photonic integrated circuits,has been realized by establishing a closed trajectory encircling EPs in anti-PTsymmetric systems,the demonstrated transmission efficiency is very low due to path-dependent ***,we demonstrate chiral dynamics in a coupled waveguide system that does not require a closed ***,we explore an open trajectory linking two infinite points having the same asymptotic eigenmodes(not modes in PT-and anti-PT-symmetric systems),demonstrating that this platform enables high-efficiency chiral transmission,with each eigenmode localized in a single *** concept is experimentally implemented in a coupled silicon waveguide system at telecommunication *** work provides a new evolution strategy for chiral dynamics with superior performance,laying the foundation for the development of practical chiral-transmission devices.

关键词： chiral system symmetric

Multi-instance partial-label learning: towards exploiting dual inexact supervision

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Science China(Information Sciences) 2024年第3期67卷 48-61页

作者： Wei TAnG Weijia zhang Min-Ling zhang School of Computer Science and Engineering Southeast University Key Laboratory of Computer network and Information Integration (Southeast University) Ministry of Education School of Information and Physical Sciences The University of Newcastle

Weakly supervised machine learning algorithms are able to learn from ambiguous samples or labels, e.g., multi-instance learning or partial-label learning. However, in some real-world tasks, each training sample is associated with not only multiple instances but also a candidate label set that contains one groundtruth label and some false positive labels. Specifically, at least one instance pertains to the ground-truth label while no instance belongs to the false positive labels. In this paper, we formalize such problems as multi-instance partial-label learning(MIPL). Existing multi-instance learning algorithms and partial-label learning algorithms are suboptimal for solving MIPL problems since the former fails to disambiguate a candidate label set, and the latter cannot handle a multi-instance bag. To address these issues, a tailored algorithm named MIPLGP, i.e., multi-instance partial-label learning with Gaussian processes, is *** first assigns each instance with a candidate label set in an augmented label space, then transforms the candidate label set into a logarithmic space to yield the disambiguated and continuous labels via an exclusive disambiguation strategy, and last induces a model based on the Gaussian processes. Experimental results on various datasets validate that MIPLGP is superior to well-established multi-instance learning and partial-label learning algorithms for solving MIPL problems.

关键词： machine learning multi-instance partial-label learning multi-instance learning partial-label learning Gaussian processes