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Radial growth in Qinghai spruce is most sensitive to severe drought in the Qilian Mountains of Northwest China

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Journal of Forestry Research 2024年第3期35卷 73-86页

作者： Xuge Wang Liang jiao Ruhong xue Peng Zhang Dashi Du Mengyuan Wei Qian Li College of Geography and Environmental Science Northwest Normal UniversityNo.967Anning East RoadLanzhou 730070People's Republic of China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou 730070Gansu ProvincePeople's Republicof China

Global warming and frequent extreme drought events lead to tree death and extensive forest decline,but the underlying mechanism is not *** drought years,cambial development is more sensitive to climate change,but in different phenological stages,the response rela-tionship is ***,the dynamic relationship between tree radial growth and climatic/environmental fac-tors needs to be *** thus continuously monitored radial growth of Qinghai spruce(Picea crassifolia Kom.)and environmental factors from January 2021 to November 2022 using point dendrometers and portable meteorological weather stations in the central area of the Qilian *** relationship and stability between the radial growth of Qinghai spruce and environmental factors were compared for different levels of drought in 2021 and *** year 2022 had higher temperatures and less precipitation and was drier than *** with 2021,the growing period in 2022 for Qinghai spruce was 10 days shorter,maximum growth rate(Grmax)was 4.5μm·d^(-1) slower,and the initiation of growth was 6 days *** of Qinghai spruce was always restricted by drought,and the stem radial increment(SRI)was more sensitive to precipitation and air relative *** changes in cumulative radial growth were divided into four phenological stages according to the time of growth onset,cessation,and maximum growth rate(Grmax)of Qinghai *** responses of SRI to climate change were stronger in Stage 3 and Stage 4 of 2021 and stronger in Stage 1(initiation growth stage)and Stage 3 of *** results provide important information on the growth of the trees in response to drought and for specific managing forests as the climate warms.

关键词： Picea crassifolia Radial growth dynamics Severe drought Response stability Point dendrometer

Carbon dots-derived three-dimensional-ordered macroporous host with high penetrability and catalytic activity for LSBs under lean electrolyte

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Rare Metals 2024年第6期43卷 2560-2573页

作者： jiao-Zi Duan Hua-Yu Pei Quan Yang xue Li Xin Ba xue Yong Jun-Ling Guo Si-Yu Lu Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China Country State Center for International Cooperation On Designer Low-Carbon&Environmental Materials School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Hubei Institute of Quality Supervision Inspection Wuhan 430061China Department of Chemistry University of SheffieldSheffeld S37HFUK

The practical energy density of lithium-sulfur batteries(LSBs)is seriously limited by the high electrolyte-to-sulfur ratios(E/S).The E/S can be reduced by employing hosts with easy-to-infiltrate structure that ensures the uniform distribution of a lean electrolyte and high catalytic activity that can suppress"shuttle effect"via accelerating the slow conversion of soluble poly sulfides to insoluble *** the easy-to-infiltrate structures,the three-dimensional-ordered macroporous(3DOM)structure is easier to scale preparation and more suitable for the existing industrial ***,it is difficult to obtain the 3DOM with(1)high penetrability due to the high viscosity of frequently-used organic polymer precursors and(2)high catalytic activity due to the low confinement effect,meaning that uniformly dispersed small-sized catalytic materials are difficult to load on ***,using carbon dots(CDs)with both organic and inorganic properties as a precursor and aggregation limiting agent,a 3DOM host with high penetrability and homodispersed Ni particles of small sizes(Ni-CDs-3DOM)was *** this host:(1)CDs precursor with suitable viscosity can improve the penetrability.(2)CDs can effectively inhibit the agglomeration of Ni particles.(3)Uniformly dispersed small-size Ni particles offer high-efficiency catalytic activity toward sulfur ***,the Ni-CDs-3DOM/sulfur cathode exhibits high sulfur utilization and stable cycling performance even under high sulfur loading(5.5 mg·cm^(-2))and low E/S(6.5μl·mg^(-1)).This work indicates the usefulness of CDs in constructing hosts for LSBs with high energy density.

关键词： Lithium-sulfur batteries Carbon dots Catalytic action Easy-to-infiltrate structure Lean electrolyte

Elevation response of above-ground net primary productivity for Picea crassifolia to climate change in Qilian Mountains of Northwest China based on tree rings

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Journal of Geographical Sciences 2024年第1期34卷 146-164页

作者： WU Xuan jiao Liang DU Dashi xue Ruhong WEI Mengyuan ZHANG Peng College of Geography and Environment Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou 730070China

Current ecosystem models used to simulate global terrestrial carbon balance generally suggest that terrestrial landscapes are stable and mature,but terrestrial net primary productivity(NPP)data estimated without accounting for disturbances in species composition,environment,structure,and ecological characteristics will reduce the accuracy of the global carbon ***,the steady-state assumption and neglect of elevation-related changes in forest NPP is a *** Qilian Mountains are located in continental climate zone,and vegetation is highly sensitive to climate *** quantified aboveground biomass(AGB)and aboveground net primary productivity(ANPP)sequences at three elevations using field-collected tree rings of Picea crassifolia in Qilian Mountains of Northwest *** results showed that(1)There were significant differences between AGB and ANPP at the three elevations,and the growth rate of AGB was the highest at the low elevation(55.99 t ha^(–1)10a^(–1)).(2)There are differences in the response relationship between the ANPP and climate factors at the three elevations,and drought stress is the main climate signal affecting the change of ANPP.(3)Under the future climate scenario,drought stress intensifies,and the predicted decline trend of ANPP at the three elevations from mid-century to the end of this century is–0.025 t ha^(–1)10a^(–1),respectively;–0.022 t ha^(–1)10a^(–1);At–0.246 t ha^(–1)10a^(–1),the level of forest productivity was significantly *** results reveal the elevation gradient differences in forest productivity levels and provide key information for studying the carbon sink potential of boreal forests.

关键词： global climate change tree ring aboveground net primary productivity aboveground biomass drought stress Qilian Mountains

A survey of composite robot for aviation intelligent manufacturing application

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High Technology Letters 2024年第1期30卷 85-98页

作者：陶永 xue jiao WEI Hongxing LIU Haitao GAO He WANG Tianmiao School of Mechanical Engineering&Automation Beihang UniversityBeijing 100191P.R.China Research Institute of Aero Engine Beihang UniversityBeijing 100191P.R.China

With the rapid development of the aviation industry,the development of intelligent manufacturing equipment represented by composite robots has been paid close attention by the aviation *** on the analysis of the background and main structure function of composite robots,this paper focuses on the analysis of key technologies such as composite robot hardware design,visual sensing and planning system,integrated control of‘hands,feet,and eyes',multi-robot collaborative operation,and *** typical applications of composite robots in aviation intelligent manufacturing such as automatic drilling and connection of aircraft,aircraft surface spraying and finishing,parts handling,aircraft measurement,and inspection are *** development trends such as standardization of composite robots,integration of‘5G+cloud computing+AI',and fusion of intelligent sensors are proposed.

关键词： aviation manufacturing composite robot key technology development trend safety

Brain Pathology in COVID-19:Clinical Manifestations and Potential Mechanisms

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Neuroscience Bulletin 2024年第3期40卷 383-400页

作者： Zhixing Xu Hui Wang Siya Jiang jiao teng Dongxu Zhou Zhong Chen Chengping Wen Zhenghao Xu First School of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310053China School of Pharmaceutical Sciences Zhejiang Chinese Medical UniversityHangzhou 310053China Second School of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310053China Afliated Lin’an People’s Hospital of Hangzhou Medical College First People’s Hospital of Hangzhou Lin’an DistrictLin’anHangzhou 311300China School of Life Sciences Zhejiang Chinese Medical UniversityHangzhou 310053China Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province College of Pharmaceutical ScienceZhejiang Chinese Medical UniversityHangzhou 310053China Laboratory of Rheumatology and Institute of TCM Clinical Basic Medicine College of Basic Medical ScienceZhejiang Chinese Medical UniversityHangzhou 310053China

Neurological manifestations of coronavirus disease 2019(COVID-19)are less noticeable than the respiratory symptoms,but they may be associated with disability and mortality in *** though Omicron caused less severe disease than Delta,the incidence of neurological manifestations is *** than 30%of patients experienced“brain fog”,delirium,stroke,and cognitive impairment,and over half of these patients presented abnormal neuroimaging *** this review,we summarize current advances in the clinical findings of neurological manifestations in COVID-19 patients and compare them with those in patients with influenza *** also illustrate the structure and cellular invasion mechanisms of SARS-CoV-2 and describe the pathway for central SARS-CoV-2 *** addition,we discuss direct damage and other pathological conditions caused by SARS-CoV-2,such as an aberrant interferon response,cytokine storm,lymphopenia,and hypercoagulation,to provide treatment *** review may offer new insights into preventing or treating brain damage in COVID-19.

关键词： COVID-19 SARS-CoV-2 Brain Neurological pathology

Rational design of vitamin C/defective carbon van der Waals heterostructure for enhanced activity,durability and storage stability toward oxygen reduction reaction

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Journal of Energy Chemistry 2024年第1期88卷 103-111,I0003页

作者： Ruiqi Cheng Kaiqi Li Huanxin Li Tianshuo Zhao Yibo Wang Qingyue xue jiao Zhang Chaopeng Fu Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Christopher Ingold Laboratory Department of ChemistryUniversity College LondonLondon WC1H 0AJUK Department of Chemistry Physical&Theoretical Chemistry LaboratoryUniversity of OxfordSouth Parks RoadOxford OX13QZUK

Metal-free defective carbon materials with abundant active sites have been widely studied as low-cost and efficient oxygen reduction reaction(ORR)electrocatalysts in metal-air ***,the active sites in defective carbon are easily subjected to serious oxidation or hydroxylation during ORR or storage,leading to rapid degradation of ***,we design a van der Waals heterostructure comprised of vitamin C(VC)and defective carbon(DC)to not only boost the activity but also enhance the durability and storage stability of the DC-VC *** formation of VC van der Waals between DC and VC is demonstrated to be an effective strategy to protect the defect active sites from oxidation and hydroxylation degradation,thus significantly enhancing the electrochemical durability and storage anti-aging ***,the DC-VC van der Waals can reduce the reaction energy barrier to facilitate the *** findings are also confirmed by operando Fourier transform infrared spectroscopy and density functional theory *** is necessary to mention that the preparation of this DC-VC electrocatalyst can be scaled up,and the ORR performance of the largely produced electrocatalyst is demonstrated to be very ***,the DC-VC-based aluminum-air batteries display very competitive power density with good performance maintenance.

关键词： Van der Waals heterostructure Oxygen reduction reaction Stability Scalable production Aluminum-air battery

Single-atom catalysis for advanced oxidation and reduction systems in water decontamination

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Rare Metals 2024年第8期43卷 3576-3606页

作者： Jie teng Jin-Hui Xu Wen-Xin Sun xue-Feng Liu Xia Xu Guo-Shuai Liu School of Urban Construction Changzhou University School of Environmental and Civil Engineering Jiangnan University

Water scarcity is an escalating global crisis,posing a severe threat to populations ***,exploring various materials to remove emerging contaminants from freshwater sources has garnered significant *** this regard,single-atom catalysis(SACs) has emerged as a catalyst of scientific progress in water purification and treatment methodologies during recent *** exhibit exceptional catalytic activity,selectivity and stability,due to their near-perfect atom utilization,highly unsaturated coordination environment and uniform reaction ***,a comprehensive and critical review encompassing the successful integration of SACs into water purification processes needs to be *** review aims to accentuate recent trends by presenting the synthesis,structure,and environment and energy application-relevant properties of *** results show that a comprehensive and multi-perspective summary of the advantages of SACs in environmental remediation can have significant benefits,such as fast kinetics,costeffectiveness,*** oxidation and reduction processes of SACs and functional SACs materials in water purification were ***,the last section is devoted to the current research gaps and further perspectives on the application of SACs in water treatment,which are summarized and analyzed.

关键词： Single-atom catalysis Water treatment Oxidation Reduction

Flexible,high-density,laminated ECoG electrode array for high spatiotemporal resolution foci diagnostic localization of refractory epilepsy

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Bio-Design and Manufacturing 2024年第4期7卷 388-398页

作者： Yafeng Liu Zhouheng Wang Yang jiao Ying Chen Guangyuan Xu Yinji Ma xue Feng Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Laboratory of Flexible Electronics Technology Tsinghua UniversityBeijing 100084China College of Artificial Intelligence Southwest UniversityChongqing 400715China Institute of Flexible Electronics Technology of THU Jiaxing 314000China Qiantang Science and Technology Innovation Center Hangzhou 310016China School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China

High spatiotemporal resolution brain electrical signals are critical for basic neuroscience research and high-precision focus diagnostic localization,as the spatial scale of some pathologic signals is at the submillimeter or micrometer *** entails connecting hundreds or thousands of electrode wires on a limited *** study reported a class of flexible,ultrathin,highdensity electrocorticogram(ECoG)electrode *** challenge of a large number of wiring arrangements was overcome by a laminated structure design and processing technology *** flexible,ultrathin,high-density ECoG electrode array was conformably attached to the cortex for reliable,high spatial resolution electrophysiologic *** minimum spacing between electrodes was 15μm,comparable to the diameter of a single *** hundred electrodes were prepared with an electrode density of 4444 mm^(-2).In focal epilepsy surgery,the flexible,high-density,laminated ECoG electrode array with 36 electrodes was applied to collect epileptic spike waves inrabbits,improving the positioning accuracy of epilepsy lesions from the centimeter to the submillimeter *** flexible,high-density,laminated ECoG electrode array has potential clinical applications in intractable epilepsy and other neurologic diseases requiring high-precision electroencephalogram acquisition.

关键词： Electrocorticogram(ECoG)electrode Epilepsy High density High resolution Laminated structure

Mixed D-vine copula-based conditional quantile model for stochastic monthly streamflow simulation

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Water Science and Engineering 2024年第1期17卷 13-20页

作者： Wen-zhuo Wang Zeng-chuan Dong Tian-yan Zhang Li Ren Lian-qing xue teng Wu College of Water Resources and Hydrology Hohai UniversityNanjing 210098China Yellow River Research Center Hohai UniversityNanjing 210098China

Copula functions have been widely used in stochastic simulation and prediction of ***,existing models are usually limited to single two-dimensional or three-dimensional copulas with the same bivariate block for all *** address this limitation,this study developed a mixed D-vine copula-based conditional quantile model that can capture temporal *** model can generate streamflow by selecting different historical streamflow variables as the conditions for different months and by exploiting the conditional quantile functions of streamflows in different months with mixed D-vine *** up-to-down sequential method,which couples the maximum weight approach with the Akaike information criteria and the maximum likelihood approach,was used to determine the structures of multivariate Dvine *** developed model was used in a case study to synthesize the monthly streamflow at the Tangnaihai hydrological station,the inflow control station of the Longyangxia Reservoir in the Yellow River *** results showed that the developed model outperformed the commonly used bivariate copula model in terms of the performance in simulating the seasonality and interannual variability of *** model provides useful information for water-related natural hazard risk assessment and integrated water resources management and utilization.

关键词： Stochastic monthly streamflow simulation Mixed D-vine copula Conditional quantile model Up-to-down sequential method Tangnaihai hydrological station