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Carbon allocation in Picea jezoensis:Adaptation strategies of a non-treeline species at its upper elevation limit

Forest Ecosystems 2024年第3期11卷 347-357页

作者： Renkai Dong Na Li Mai-he Li Yu Cong Haibo Du Decai Gao hong.s.he Key Laboratory of Geographical Processes and Ecological security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China school of Natural Resources University of MissouriColumbiaMO65211USA swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun130102China school of Life science Hebei UniversityBaoding071002China

Understanding the physiological adaptations of non-treeline trees to environmental stress is important to understand future shifts in species composition and distribution of current treeline *** aim of the present study was to elucidate the mechanisms of the formation of the upper elevation limit of non-treeline tree species,Picea jezoensis,and the carbon allocation strategies of the species on Changbai *** employed the^(13)C in situ pulse labeling technique to trace the distribution of photosynthetically assimilated carbon in Picea jezoensis at different elevational positions(tree species at its upper elevation limit(TsAUE,1,700 m a.s.l.)under treeline ecotone;tree species at a lower elevation position(TsALE,1,400 m a.s.l.).We analyzed^(13)C and the non-structural carbohydrate(NsC)concentrations in various tissues following *** findings revealed a significant shift in carbon allocation in TsAUE compared to *** was a pronounced increase inδ^(13)C allocation to belowground components(roots,soil,soil respiration)in TsAUE compared to ***,the C flow rate within the plant-soil-atmosphere system was faster,and the C residence time in the plant was shorter in *** trends indicate enhanced C sink activity in belowground tissues in TsAUE,with newly assimilated C being preferentially directed there,suggesting a more conservative C allocation strategy by *** at higher elevations under harsher *** a strategy,prioritizing C storage in roots,likely aids in withstanding winter cold stress at the expense of aboveground growth during the growing season,leading to reduced growth of TsAUE compared to *** results of the present study shed light on the adaptive mechanisms governing the upper elevation limits of non-treeline trees,and enhances our understanding of how non-treeline species might respond to ongoing climate change.

关键词： ^(13)C pulse labeling Carbon distribution Non-structural carbohydrates(NsC) Non-treeline species sink activity stressful environments Upper elevation limit

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Review on synergistic damage effect of irradiation and corrosion on reactor structural alloys

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Nuclear science and Techniques 2024年第3期35卷 109-141页

作者： Hui Liu Guan-hong Lei he-Fei Huang shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China school of Nuclear science and Technology University of Chinese Academy of SciencesBeijing 100049China

The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research *** paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt *** competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this *** approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors.

关键词： Irradiation and corrosion synergistic effect Austenitic stainless steels Nickel-based alloys Reactors

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Restoring cosmological concordance with axion-like early dark energy and dark matter characterized by a constant equation of state?

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Communications in Theoretical Physics 2024年第7期76卷 74-82页

作者： Yan-hong Yao Xin-he Meng school of Physics and Astronomy Sun Yatsen University 2 Daxue RoadTangjiaZhuhaiChina school of Physics Nankai University 94 Weijin RoadNankaiTianjinChina

The Hubble tension persists as a challenge in *** early dark energy(EDE)models,initially considered the most promising for alleviating the Hubble tension,fall short of addressing the issue without exacerbating other tensions,such as the s_(8)*** that a negative dark matter(DM)equation of state(Eos)parameter is conducive to reduce the value of the σ_(8)parameter,we extend the axion-like EDE model in this paper by replacing the cold dark matter(CDM)with DM characterized by a constant Eos w_(dm)(referred to as WDM hereafter).We then impose constraints on this axion-like EDE extension model,along with three other models:the axion-like EDE model,ΛWDM,and Λ*** constraints are derived from a comprehensive analysis incorporating data from the Planck 2018 cosmic microwave background,baryon acoustic oscillations,and the Pantheon compilation,as well as a prior on H_(0)(i.e.H_(0)=73.04±1.04,based on the latest local measurement by Riess et al)and a Gaussianized prior on s_(8)(i.e.s_(8)=0.766±0.017,determined through the joint analysis of KID1000+BOss+2dLens).We find that although the new model maintains the ability to alleviate the Hubble tension to~1.4σ,it still exacerbates the s_(8)tension to a level similar to that of the axion-like EDE model.

关键词： Hubble tension early dark energy noncold dark matter s8 tension

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Combating periodontitis with an ATP-responsive metal-organic framework through synergistic ion-interference-induced pyroptosis

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science China Chemistry 2024年第11期67卷 3493-3494页

作者： Yuling Xu Mengrong he Xuechuan hong state Key Laboratory of Green Pesticide International Joint Research Center for Intelligent Biosensor Technology and HealthCollege of Chemistry Central China Normal University Department of Ultrasound Medicine Union Hospital Tongji Medical College Huazhong University of Science and Technology Department of Cardiology Clinic Trial Center Zhongnan Hospital of Wuhan University School of Pharmaceutical SciencesWuhan University

Periodontitis is indeed a chronic inflammatory disease caused by microorganisms, and it is a leading cause of tooth loss in adults worldwide [1–3]. The immune system typically maintains a balance with pathogenic bacteria in the body, and the local mucosal immune system effectively monitors and controls these microorganisms to prevent excessive inflammation.

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Design of double protograph LDPC codes based JsCC systems via the ACE-PEG algorithm

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science China(Information sciences) 2024年第7期67卷 339-340页

作者： Yijie LV Jiguang he shaohua hong Department of Information and Communication Engineering Xiamen University Technology Innovation Institute Centre for Wireless Communications Oulu University

In this study, we present a state-of-the-art design of double protograph low-density parity-check (DP-LDPC) codes based on progressive edge-growth (PEG) algorithm with approximated cycle extrinsic message degree (ACE)... 详细信息

关键词： Benchmarking

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Perception of fundamental science to boost lithium metal anodes toward practical application

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Green Energy & Environment 2024年第3期9卷 454-472页

作者： Jinkun Wang Li Wang hong Xu Li sheng Xiangming he Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China

As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference *** lithium anodes are regarded as the holy grail of lithium batteries,decades of exploration have not led to the successful commercialization of LMBs,due mainly to the challenges related to the inherent properties of lithium *** pave the way for further investigation,herein,a comprehensive review focusing on the fundamental science of lithium are ***,the natures of lithium atoms and their isotopes,lithium clusters and lithium crystals are revisited,especially their structural and energetic ***,the electrochemical properties of lithium metal are *** important concepts and scientific questions,including the electronic structure of lithium,influence of high pressure and low temperature on the properties of lithium,factors influencing lithium deposition,generation of lithium dendrites,and electrode potential of lithium in different electrolytes,are explained and analyzed in *** to improve the performance of lithium anodes and thoughtfulness about the electrode potential in lithium battery research are proposed.

关键词： Lithium Cluster Crystal Physicochemical property Fundamental science

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Rapid Energy Exchange between In situ Formed Bromine Vacancies and CO_(2)Molecules Enhances CO_(2)Photoreduction

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Research 2024年第2期2023卷 763-771页

作者： Qin Ren Ye he hong Wang Yanjuan sun Fan Dong Research Center for Environmental and Energy Catalysis Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 611731China school of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China

Photocatalytic reduction of CO_(2)into fuels provides a prospective tactic for regulating the global carbon balance utilizing renewable solar ***,CO_(2)molecules are difficult to activate and reduce due to the thermodynamic stability and chemical *** this work,we develop a novel strategy to promote the adsorption and activation of CO_(2)molecules via the rapid energy exchange between the photoinduced Br vacancies and CO_(2)*** in situ continuous wave-electron paramagnetic resonance(cw-EPR)and pulsed EPR technologies,we observe that the spin-spin relaxation time(T_(2))of BiOBr is decreased by 198 ns during the CO_(2)photoreduction reaction,which is further confirmed by the broadened EPR *** result reveals that there is an energy exchange interaction between in situ formed Br vacancies and CO_(2)molecules,which promotes the formation of high-energy CO_(2)molecules to facilitate the subsequent reduction *** addition,theoretical calculations indicate that the bended CO_(2)adsorption configuration on the surface of BiOBr with Br vacancies caused the decrease of the lowest unoccupied molecular orbital of the CO_(2)molecule,which makes it easier for CO_(2)molecules to acquire electrons and get *** situ diffuse reflectance infrared Fourier transform spectroscopy further shows that the activated CO_(2)molecules are favorably converted to key intermediates of COOH*,resulting in a CO generation rate of 9.1μmol g^(-1)h^(-1)and a selectivity of 100%.This study elucidates the underlying mechanism of CO_(2)activation at active sites and deepens the understanding of CO_(2)photoreduction reaction.

关键词： reaction. adsorption activation

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Does back cooling improve human thermal comfort in warm environments?A device for heat conduction by the semiconductor Peltier effect

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Building simulation 2024年第8期17卷 1253-1271页

作者： Mengyuan he hong Liu Lianggen shao Baizhan Li Yuxin Wu Joint International Research Laboratory of Green Building and Built Environments(Ministry of Education) Chongqing UniversityChongqingChina National Centre for International Research of Low-carbon and Green Buildings(Ministry of science and Technology) Chongqing UniversityChongqingChina school of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhouChina

The hot environment and the metabolic heat of commuting in summer caused individual overheating and intense thermal *** cooling presents huge potential for optimizing thermal *** study investigates the performance of a back cooling device,based on the semiconductor Peltier effect,in improving thermal comfort after summer *** studied one case without cooling,and three cases with surface temperatures of the cooling device of 29,27,and 25℃using a simulated summer commute at a moderate activity *** results showed that thermal sensation,perceived sweating rate,and skin temperature decreased markedly in the cooling cases compared to the non-cooling case,with the changes being most notable in the lower back,in contact with the cooling *** decrease in overall thermal sensation and mean skin temperature was approximately 0.52 score and 0.31℃on average,respectively,with a 1.71 score increase in overall thermal *** contend that the surface temperature of local contact cooling devices should not be lower than 22℃to minimize local *** cooling devices present a huge potential for building energy-savings at ambient air temperature exceeding 30℃.Moreover,the functional paradigms for individual comfort predict improved comfort performance in future *** study contributes to the understanding on the well-being and physiological recovery of individuals after a summer commuting.

关键词： back cooling heat conduction summer commuting thermal comfort prediction

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Processing of a low-costγ-γ'NiPtAl coating with improved oxidation resistance

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Rare Metals 2024年第6期43卷 2832-2841页

作者： Yan Jiang Liang-Liang Wei Jian he hong-Bo Guo school of Materials science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature structural Materials and Protective Coatings Ministry of Industry and Information TechnologyBeihang UniversityBeijing 100191China

A novelγ-γ'(Ni solid solution—Ni_(3)Al)NiPtAl coating was produced on advanced single-crystal(sC)superalloy N5 by electroplating of a thin Pt coating with~3μm in thickness followed by heat treatment at 1000℃in *** comparison,a traditionalγ-γ'NiPtAl coating was also produced by electroplating of a thick Pt coating with~6μm in thickness followed by heat treatment at 1100℃in *** novel coating has a mass gain of~0.5 mg·cm^(-2)after 100 h 1-h cyclic oxidation at 1150℃,showing better oxidation resistance than the traditional *** oxide scale mostly consisting ofα-Al_(2)O_(3)grew on the novel coating because the element Cr from the sC alloy substrate contributes to the formation ofα-Al_(2)O_(3).Pt content in the novel coating has significant effect on the oxidation *** optimized Pt content in the coating is about 16 at%,which is helpful to reduce the diffusion of harmful elements from the substrate into the coating but also to reduce the cost of the coating.

关键词： γ-γ'NiPtAl coating Platinum Oxidation Al_(2)O_(3) superalloy

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Optimizing near-carbon-free nuclear energy systems:advances in reactor operation digital twin through hybrid machine learning algorithms for parameter identification and state estimation

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Nuclear science and Techniques 2024年第8期35卷 177-203页

作者： Li‑Zhan hong he‑Lin Gong hong‑Jun Ji Jia‑Liang Lu Han Li Qing Li Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China science and Technology on Reactor system Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy *** previous studies,we developed a reactor operation digital twin(RODT).However,non-differentiabilities and discontinuities arise when employing machine learning-based surrogate forward models,challenging traditional gradient-based inverse methods and their *** study investigated deterministic and metaheuristic algorithms and developed hybrid algorithms to address these *** efficient modular RODT software framework that incorporates these methods into its post-evaluation module is presented for comprehensive *** methods were rigorously assessed based on convergence profiles,stability with respect to noise,and computational *** numerical results show that the hybrid KNNLHs algorithm excels in real-time online applications,balancing accuracy and efficiency with a prediction error rate of only 1%and processing times of less than 0.1 ***,algorithms such as FsA,DE,and ADE,although slightly slower(approximately 1 s),demonstrated higher accuracy with a 0.3%relative L_2 error,which advances RODT methodologies to harness machine learning and system modeling for improved reactor monitoring,systematic diagnosis of off-normal events,and lifetime management *** developed modular software and novel optimization methods presented offer pathways to realize the full potential of RODT for transforming energy engineering practices.

关键词： Parameter identification state estimation Reactor operation digital twin Reduced order model Inverse problem

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