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Research progresses and prospects of multi-sphere compound extremes from the Earth System perspective

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Science China Earth Sciences 2024年第2期67卷 343-374页

作者： Zengchao HAO yang CHEN College of Water Sciences Beijing Normal UniversityBeijing100875China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing100081China

Compound extremes,whose socioeconomic and ecological impacts are severer than that caused by each event occurring in isolation,have evolved into a hot topic in Earth Science in the past *** the context of climate change,many compound extremes have exhibited increasing frequency and intensity,and shown novel fashions of combinations,posing more pressing demands and tougher challenges to scientific research and disaster prevention and *** article,via a perspective of multi-sphere interactions within the Earth System,systematically reviews the status quo,new scientific understanding,and deficiencies regarding the definition,mechanism,change,attribution,and projection of compound *** study also sorts out existing challenges and outlines a potential roadmap in advancing the study on compound extremes with respect to data requirement,mechanistic diagnosis,numerical modeling,attribution and projection,risk assessment,and adaptive *** directions of compound extremes studies and key research topics that warrant multi-disciplinary and multisectoral coordinated efforts are also *** that climate change has reshaped the type of extremes,a transformation from the traditional single-event perspective to a compound-event perspective is needed for scientific research,disaster prevention and mitigation,and climate change adaptation,calling for bottom-up innovation in research objects,ideas,and *** article will add value to promoting the research on compound extremes and interdisciplinary cooperations.

关键词： Extremes Compound extremes Climate change and risk Multi-sphere interactions

Chiral liquid crystal elastomers advance light modulation

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Light(Science & Applications) 2024年第9期13卷 1698-1700页

作者： Jiazhe Ma Zhongqiang yang Department of Chemistry Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of EducationTsinghua UniversityBeijing 100084China Laboratory of Flexible Electronics Technology Tsinghua UniversityBeijing 100084China

Chiral liquid crystal elastomers,as soft photonic materials,enable dynamic omnidirectional tuning of circularly polarized reflection wavelength and function as an effective medium for full-color circularly polarized l... 详细信息

关键词： Chiral crystal circular

Crystalline-amorphous M@MN_x(M=Co,Fe,Ni)encapsulated in nitrogen-doped carbon for enhanced efficient and durable hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1547-1556页

作者： yang yang Xiao-Chuan Duan Shao-Hui Guo Xian-Ming Zhang College of Materials Science and Engineering College of ChemistryKey Laboratory of Interface Science and Engineering in Advanced MaterialsTaiyuan University of TechnologyYuci030600China

Developing earth-abundant electrocatalysts for hydrogen evolution reaction(HER)is important for the sustainable energy ***,efficient and stable heterocatalysts consisting of crystalline-amorphous M@MN_(x)(M=Co,Fe,Ni)encapsulated in N-doped carbon layers supported with N-doped graphene sheets(denoted as M@MN_(x)@NC-NG)are synthesized by facile hydrothermal reaction and nitridation *** the nitriding process,metal ions in M(tzbc)_2(H_(2)O)_4(tzbc=4-(1H-1,2,4-triazol-1-yl)benzoic acid)complexes are reduced to crystalline M cores,accompanied by the formation of amorphous MN_(x)shells;the tzbc ligands are insitu carbonized to form outermost N-doped carbon(NC)layers that connect with inner MN_(x)via M-N-C motifs inherited from the complex precursors and inhibit the transition of MN_(x)from amorphous to crystalline *** Co@CoN_(x)@NC-NG catalyst exhibits excellent HER activity with small overpotentials of 45 and 64 mV at a cathode current density of 10 mA·cm^(-2)and low Tafel slopes of 40 and 85 mV·dec^(-1)in 0.5 mol·L^(-1)H_(2)SO_4 and1.0 mol·L^(-1)KOH electrolytes,*** Co@CoN_(x)@NC-NG retains 97%of the initial overpotential after 100,000 s in both acidic and alkaline *** outstanding HER performance originates from the crystalline-amorphous Co@CoN_(x)that redistributes electrons around the heterointerfaces,facilitating the conversion process of H^(+)/H_(2)O to hydrogen and thereby promoting HER *** outermost NC layers serve as the armor of Co@CoN_(x),and graphene nanosheets act as carriers of egg-like Co@CoN_(x)@NC and conduction paths for electron shuttles,ensuring stable and continuous electrocatalytic hydrogen production.

关键词： Hydrogen evolution reaction Electrocatalysts Iron group metals Heterojunction Crystalline-amorphous structure

Bioinspired supramolecular macrocycle hybrid membranes with enhanced proton conductivity

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Nano Research 2024年第2期17卷 797-805页

作者： Pengfei yang Linlin Xu Panagiotis Trogadas Marc-Olivier Coppens yang Lan Centre for Nature Inspired Engineering Department of Chemical EngineeringUniversity College LondonLondon WC1E 7JEUK

Enhancing the proton conductivity of proton exchange membranes(PEMs)is essential to expand the applications of proton exchange membrane fuel cells(PEMFCs).Inspired by the proton conduction mechanism of bacteriorhodopsin,cucurbit[n]urils(CB[n],where n is the number of glycoluril units,n=6,7,or 8)are introduced into sulfonated poly(ether ether ketone)(SPEEK)matrix to fabricate hybrid PEMs,employing a nature-inspired chemical engineering(NICE)*** carbonyl groups of CB[n]act as proton-conducting sites,while the host–guest interaction between CB[n]and water molecules offers extra protonconducting ***,the molecular size of CB[n]aids in their dispersion within the SPEEK matrix,effectively bridging the unconnected proton-conducting sulfonic group domains within the SPEEK ***,all hybrid membranes exhibit significantly enhanced proton ***,the SPEEK membrane incorporating 1 wt.%CB[8](CB[8]/SPEEK-1%)demonstrates the highest proton conductivity of 198.0 mS·cm^(−1) at 60°C and 100%relative humidity(RH),which is 228%greater than that of the pure SPEEK membrane under the same ***,hybrid membranes exhibit superior fuel cell *** CB[8]/SPEEK-1%membrane achieves a maximum power density of 214 mW·cm^(−2),representing a 140%improvement over the pure SPEEK membrane(89 mW·cm^(−2))at 50°C and 100%*** findings serve as a foundation for constructing continuous proton-conducting pathways within membranes by utilizing supramolecular macrocycles as fuel cell electrolytes and in other applications.

关键词： supramolecular macrocycle proton conductivity cucurbit[n]uril proton exchange membrane fuel cell

A digital twins enabled underwater intelligent internet vehicle path planning system via reinforcement learning and edge computing

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Digital Communications and Networks 2024年第2期10卷 282-291页

作者： Jiachen yang Meng Xi Jiabao Wen yang Li Houbing Herbert Song School of Electrical and Information Engineering Tianjin UniversityTianjin300072China Security and Optimization for Networked Globe Laboratory(SONG Lab) Embry-Riddle Aeronautical UniversityDaytona BeachFL32114USA

The Autonomous Underwater Glider(AUG)is a kind of prevailing underwater intelligent internet vehicle and occupies a dominant position in industrial applications,in which path planning is an essential *** to the complexity and variability of the ocean,accurate environment modeling and flexible path planning algorithms are pivotal *** traditional models mainly utilize mathematical functions,which are not complete and *** existing path planning algorithms depend on the environment and lack *** overcome these challenges,we propose a path planning system for underwater intelligent internet *** applies digital twins and sensor data to map the real ocean environment to a virtual digital space,which provides a comprehensive and reliable environment for path *** design a value-based reinforcement learning path planning algorithm and explore the optimal network structure *** path simulation is controlled by a closed-loop model integrated into the terminal vehicle through edge *** integration of state input enriches the learning of neural networks and helps to improve generalization and *** task-related reward function promotes the rapid convergence of the *** experimental results prove that our reinforcement learning based path planning algorithm has great flexibility and can effectively adapt to a variety of different ocean conditions.

关键词： Digital twins Reinforcement learning Edge computing Underwater intelligent internet vehicle Path planning

Deficiency of Trp53 and Rb1 in myeloid cell lineage spontaneously develops acute myeloid leukemia in a mouse model

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Genes & Diseases 2024年第1期11卷 4-6页

作者： yang Li Shu-ting yang Shuying yang Department of Basic&Translational Sciences School of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA Department of Orthopaedic Surgery School of MedicineJohns Hopkins University BaltimoreMD 21205USA Center for Innovation&Precision Dentistry School of Dental MedicineSchool of Engineering and Applied SciencesUniversity of PennsylvaniaPhiladelphiaPA 19104USA The Penn Center for Musculoskeletal Disorders School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA

Acute myeloid leukemia(AML)is a rapidly lethal blood cancer characterized by aberrant proliferation and differentiation of myeloid progenitors in the hematopoietic *** recent decades,AML patients are significantly *** 2019 alone,21,450 new AML cases were diagnosed in the United States,with an estimated 10,920 deaths due to ***’s worse,AML occurs with an increasing incidence with advanced age,and the survival rate remains dismal with a median overall survival of only 5e10 *** great advances in allogenic transplant and chemotherapy,the therapeutic outcomes are unfavorable due to the disease relapse and mortality *** importantly,the development of more specific and effective therapies was hampered in part by the lack of proper animal models for ***,management and elucidation of the pathological mechanism of AML remain an ongoing challenge,and the development of effective AML mouse models and treatment options are urgently needed.

关键词： myeloid Acute leukemia

Origin of nucleation and growth of extension twins in grains unsuitably oriented for twinning during deformation of Mg-1%Al

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Journal of Magnesium and Alloys 2024年第3期12卷 1186-1203页

作者： Biaobiao yang Javier LLorca IMDEA Materials Institute C/Eric Kandel 2GetafeMadrid 28906Spain Department of Materials Science Polytechnic University of Madrid/Universidad Politécnica de MadridE.T.S.de Ingenieros de CaminosMadrid 28040Spain

A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded *** deformation mechanisms responsible for this behaviour were investigated through in-situ electron back-scattered diffraction,grain reference orientation deviation,and slip trace-modified lattice *** was found that anomalous extension twins nucleated mainly at the onset of plastic deformation at or near grain boundary triple *** were associated with the severe strain incompatibility between neighbour grains as a result from the differentbasal slip-induced lattice ***,the anomalous twins were able to grow with the applied strain due to the continuous activation ofbasal slip in different neighbour grains,which enhanced the strain *** results reveal the complexity of the deformation mechanisms in Mg alloys at the local level when deformed along hard orientations.

关键词： Magnesium Extension twinning In-situ electron back-scattered diffraction basal slip Deformation mechanisms.

Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu yang Li Yu Liu Xiao-Xiao Ling Li-Guang Wu Li yang Lan yang Bo yang Yong-Gang Zhao Xian-Hua Li State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

High-entropy sulfurization enables efficient non-noble metal-based NiCoFeCuS electrocatalyst for alkaline oxygen evolution reaction

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Particuology 2024年第10期93卷 180-185页

作者： Pan yang Mengxiang Sun Jingchuan Wang Jinfeng Li Ruizhu yang Yawei Hao Li Qi Lijun yang Xue Liu Institute of Materials China Academy of Engineering PhysicsJiangyou621908China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou621907China

Highly active and cost-effective oxygen evolution reaction electrocatalysts have become essential to replace commercial electrocatalysts that rely on rare noble ***-entropy sulfide nanomaterials,characterized by abundant randomly distributed elements and inherent stability,possess significant potential for ***,challenges such as uneven composition,partial oxidation,or imprecise synthesis control still remain in the materials ***,a simple and effective two-step hydrothermal method was employed to synthesize NiCoFeCuS nanoparticles supported on foam nickel *** the catalytic active sites produced by electron density redistribution in high-entropy and sulfurization,NiCoFeCuS exhibits excellent alkaline OER performance,with an overpotential of 261 mV and a Tafel slope of 57.97 mV dec^(−1) at the current density of 10 mA cm^(−2),which is only 88%of commercial RuO_(2) without any noble metals.

关键词： High-entropy Sulfurization NiCoFeCuS electrocatalyst Oxygen evolution reaction Overpotentials