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Climate and topography regulate the spatial pattern of soil salinization and its effects on shrub community structure in Northwest China

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Journal of Arid land 2024年第7期16卷 925-942页

作者： DU lan tian Shengchuan ZHAO Nan ZHANG Bin MU Xiaohan TANG Lisong ZHENG Xinjun LI Yan State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Fukang Station of Desert Ecology Chinese Academy of SciencesFukang 831505China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China

Soil salinization may affect biodiversity and species composition,leading to changes in the plant community ***,few studies have explored the spatial pattern of soil salinization and its effects on shrub community structure at the ecosystem ***,we conducted a transect sampling of desert shrublands in Northwest China during the growing season(June–September)in *** salinization(both the degree and type),shrub community structure(e.g.,shrub density and height),and biodiversity parameters(e.g.,Simpson diversity,Margalf abundance,Shannon-Wiener diversity,and Pielou evenness indices)were used to assess the effects of soil salinization on shrub community *** results showed that the primary degree of soil salinization in the study area was light salinization,with the area proportion of 69.8%.Whereas the main type of soil salinization was characterized as sulfate saline soil,also accounting for 69.8%of the total ***,there was a significant reduction in the degree of soil salinization and a shift in the type of soil salinization from chloride saline soil to sulfate saline soil,with an increase in *** mean annual precipitation(MAP),mean annual evapotranspiration(MAE),elevation,and slope significantly contributed to soil salinization and its geochemical *** soil salinization intensified,shrub community structure displayed increased diversity and evenness,as indicated by the increases in the Simpson diversity,Shannon-Wiener diversity,and Pielou evenness ***,the succulent stems and leaves of Chenopodiaceae and Tamaricaceae exhibited clear advantages under these ***,regional climate and topography,such as MAP,MAE,and elevation,had greater effects on the distribution of shrub plants than soil *** results provide a reference for the origin and pattern of soil salinization in drylands and their effects on the community structure of halophyte shrub species.

关键词： soil salinization halophytes shrubland climate change biodiversity drylands Northwest China

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Evolution exploration and structure prediction of Keggin-type group IVB metal-oxo clusters

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Chinese Chemical Letters 2024年第5期35卷 487-492页

作者： Run-Han Li tian-Yi Dang Wei Guan Jiang Liu Ya-Qian lan Zhong-Min Su School of Chemistry South China Normal UniversityGuangzhou 510006China Institute of Functional Material Chemistry Faculty of ChemistryNortheast Normal UniversityChangchun 130024China Institute of Theoretical Chemistry Jilin UniversityChangchun 130023China

The fascinating chemical structure and broad application prospect of Keggin-type polyoxometalates(POMs)have attracted many chemists to explore and discover *** the traditional Keggin,larger metal atomic radius,higher metal coordinated numbers,lower metal valence states and other features allow the group IVB metal-based Keggin(IVB-Keggin)more space and unknown in terms of structure and ***,density functional theory(DFT)calculations were performed to explore the influences including cores,shells,caps,and terminal ligands,et *** IVB-Keggin,and analyze the possibility of novel structure *** the perspective of multi-layer onion-like clusters,molecular energy level,host-guest interaction energy,surface charge and covalent bond polarity can be further adjusted to achieve the oriented design of functional *** insights are expected to provide theoretical support for experimental synthesis,opening a new perspective to understand the growth of Keggin.

关键词： Keggin Metal-oxo clusters Group IVB Onion pattern DFT

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Evaluating soil acidification risk and its effects on biodiversity–ecosystem multifunctionality relationships in the drylands of China

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Forest Ecosystems 2024年第2期11卷 162-171页

作者： lan Du Shengchuan tian Nan Zhao Bin Zhang Xiaohan Mu Lisong Tang Xinjun Zheng Yan Li State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi830011XinjiangChina University of Chinese Academy of Sciences Beijing100049China Fukang Station of Desert Ecology Chinese Academy of SciencesFukang831505XinjiangChina State Key Laboratory of Subtropical Silviculture Zhejiang A and F UniversityHangzhou311300ZhejiangChina

Background:Soil acidifcationn caused by anthropogenic activities may aft soil biochemical cydling,bidiversity,productivity,and multiple eosystem-related functions in ***,to date,such information is lacking to support this *** Based on a transect survey of 78 naturally assembled shrub communities,we caloulated acid deposition flux in Northwest China and evaluated its likely ecological ffets by testing three altemnative hypotheses,namely:.nidche complementarity,mass ratio,and vegetation quantity hypotheses Rao's quadratic entopy and community-weighted mean traits were employed to represent the complementary aspect of niche complementarity and mass ratio effects,***:We observed that in the past four decades,the concentrations of exchangeable base cations in soil in Northwest China have decreased significantly to the extent of having faced the risk of depletion,whereas changes in the calium carbonate content and pH of soil were not *** deposition primani ly increased the aboweground biomass and shrub density in shrublands but had no sigmificant effect on shrub richness and ecasystem multifunctionality(EMF),indicating that acid deposition had positive but weak ecological effects on dryland *** wd ghted mean of functional traits(representing the mass ratio hypothesis)correlated negatively with EMF,whereas both Rao's quadratic entropy(representing the niche complementarity hypothesis)and aboveground biomass(representing the vegetation quantity hypothesis)correlated positively but insignifcantly with *** biodiversity-EMF relationships highlight the fragility and instability of drylands relative to forest ***:The findings from this study serve as important reference points to understand the ris of soil acidification in arid regions and its impacts on biodiversity-EMF relationships.

关键词： Soil acidification risk Biodiversity Ecosystem multifunctionality Niche complementarity hypothesis Mass ratio hypothesis Vegetation quantity hypothesis

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Unveiling inverse vulcanized polymers as metal-free,visible-light-driven photocatalysts for cross-coupling reactions

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Chinese Chemical Letters 2024年第4期35卷 142-146页

作者： lang Gao Cen Zhou Rui Wang feng lan Bohang An Xiaozhou Huang Xiao Zhang Fujian Key Laboratory of Polymer Science Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical EngineeringCollege of Chemistry and Materials ScienceFujian Normal UniversityFuzhou 350007China Fujian Engineering and Research Center of New Chinese Lacquer Materials College of Materials and Chemical EngineeringMinjiang UniversityFuzhou 350108China

Inverse vulcanized polymers(IVPs) that generated from elemental sulfur and smaller amounts of alkenes have found broad promising applications such as cathode materials for Li-S batteries, dynamic and repairable materials, optics applications, and metal sorption. However, their exploration in organic synthesis is still unprecedented. Here we first report the application of inverse vulcanized polymers in catalysis for organic transformations. A biomass-derived inverse vulcanized polymer(IVP-EAE) is found to be capable of catalyzing cross-coupling reactions in a transition-metal-free fashion under visible *** method allows the direct C–H functionalization of pyrroles and N-arylacrylamides with(hetero)aryl halides, respectively, leading to the formation of two sets of structurally important scaffolds including pyrrole-containing biaryls and 3,3-disubstituted oxindoles with high selectivity. We anticipate this study will not only unveil the new potential of IVPs, but also offer a distinct type of catalysts for organic transformations.

关键词： Cross coupling Inverse vulcanized polymers Metal free Photocatalyst Visible light

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Probabilistic modeling of multifunction radars with autoregressive kernel mixture network

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Defence Technology（防务技术） 2024年第5期35卷 275-288页

作者： Hancong feng Kaili.Jiang Zhixing Zhou Yuxin Zhao Kailun tian Haixin Yan Bin Tang School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

The task of modeling and analyzing intercepted multifunction radars(MFRs)pulse trains is vital for cognitive electronic *** methodologies predominantly rely on prior information or heavily constrained models,posing challenges for non-cooperative *** paper introduces a novel approach to model MFRs using a Bayesian network,where the conditional probability density function is approximated by an autoregressive kernel mixture network(ARKMN).Utilizing the estimated probability density function,a dynamic programming algorithm is proposed for denoising and detecting change points in the intercepted MFRs pulse *** results affirm the proposed method's efficacy in modeling MFRs,outperforming the state-of-the-art in pulse train denoising and change point detection.

关键词： Probabilistic forecasting Multifunction radar Unsupervised learning Change point detection Outlier detection

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Synthesis,phase transformation and applications of CeCO_(3)OH:A review

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Journal of Rare Earths 2024年第8期42卷 1403-1420,I0001页

作者： Zhou Zou Weihao tian Xisong Mao Junqi Li Yuanpei lan Chaoyi Chen Hong Yong Sohn Junshan Zhang fengyuan Liu Department of Metallurgical Engineering College of Materials and MetallurgyGuizhou UniversityGuiyang55025China Guizhou Province Key Laboratory of Metallurgical Engineering and Process Energy Saving Guiyang550025China Guizhou Provincial University Key Laboratory of High-Performance Battery Materials Guiyang550025China Department of Materials Science and Engineering University of UtahSalt Lake CityUT84112USA

CeCO_(3)OH has a unique crystal structure and excellent optical,electronic and catalytic properties,which has been widely investigated for many ***,ceria obtained from CeCO_(3)OH has a morphology that is similar to that of the precursor,and the CeO_(2)-based products obtained from CeCO_(3)OH exhibit outstanding properties,such as catalytic performances,owing to their designed morphology and oxygen vacancies(OVs).To introduce CeCO_(3)OH into a wider range of potential researchers,we first systematically review the physico-chemical properties,synthesis,reaction and morphology tuning mechanism of CeCO_(3)OH,and summarize the conversion behavior from CeCO_(3)OH to ***,we thoroughly survey the applications of CeCO_(3)OH and its conversion *** for further investigations of CeCO_(3)OH are also made in this *** is hoped that the exhaustive co mpilation of the valuable properties and considerable potential investigations of CeCO_(3)OH will promote further applications of CeCO_(3)OH and CeO_(2)-based functional materials.

关键词： CeCO_(3)OH Morphology tuning CeO_(2) Catalyst lanthanide compounds Rare earths

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Generation of multiphoton quantum states on silicon

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Light(Science & Applications) 2019年第1期8卷 811-817页

作者： Ming Zhang lan-tian feng Zhi-Yuan Zhou Yang Chen Hao Wu Ming Li Shi-Ming Gao Guo-Ping Guo Guang-Can Guo Dao-Xin Dai Xi-feng Ren State Key Laboratory for Modern Optical Instrumentation Centre for Optical and Electromagnetic ResearchZhejiang Provincial Key Laboratory for Sensing TechnologiesCollege of Optical Science and EngineeringZhejiang UniversityZijingang CampusHangzhou 310058China Ningbo Research Institute Zhejiang UniversityNingbo 315100China Key Laboratory of Quantum Information CASUniversity of Science and Technology of ChinaHefeiAnhui 230026China Synergetic Innovation Center of Quantum Information&Quantum Physics University of Science and Technology of ChinaHefeiAnhui 230026China

Multiphoton quantum states play a critical role in emerging quantum technologies and greatly improve our fundamental understanding of the quantum *** photonics is well recognized as an attractive technology offering great promise for the generation of photonic quantum states with high-brightness,tunability,stability,and ***,we demonstrate the generation of multiphoton quantum states using a single-silicon nanophotonic *** detected four-photon rate reaches 0.34 Hz even with a low-pump power of 600μ*** multiphoton quantum state is also qualified with multiphoton quantum interference,as well as quantum state *** the generated four-photon states,the quantum interference visibilities are greater than 95%,and the fidelity is 0.78±***,such a multiphoton quantum source is fully compatible with the on-chip processes of quantum manipulation,as well as quantum detection,which is helpful for the realization of large-scale quantum photonic integrated circuits(QPICs)and shows great potential for research in the area of multiphoton quantum science.

关键词： quantum multiphoton realization

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A Study on the Role of Tourism in Enhancing Personal Mental Health in the Post-Epidemic Era

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International Journal of Mental Health Promotion 2024年第4期26卷 325-334页

作者： Ruiqin tian Yue feng Lingqi Zhan School of Mathematics Hangzhou Normal UniversityHangzhou311121China

With the advent of the post-epidemic era,a great wave of tourism has been ushered in *** relationship between tourism and mental health has become a hot topic in *** paper investigates the enhancement of people’s mental health after tourism through social *** Hangzhou as the sample collection site,this paper conducted a study on the role of tourism in enhancing personal mental health through descriptive analysis,factor analysis and structural equation modeling,and further specifically analyzed the role of mediating *** results showed that:(1)The purpose of tourism is to relax and relieve stress,and the effectiveness of tourism is mainly reflected in the alleviation of emotional conditions;(2)Factor Analysis reduced the dimensionality of personal mental health indicators,and finally obtained four factors,among which the comprehensive behavioral ability and physiological manifestation had the best improvement effect after tourism;(3)The structural equation model shows that the enhancing effect of tourism on mental health originates from the factor of inner psychological characteristic,and this factor works through two paths:Inner Psychological Characteristic-Social Adaptability-Physiological Manifestations-Enhancement of Mental Health by Tourism,and Inner Psychological Characteristic-Comprehensive Behavioral Ability-Enhancement of Mental Health by Tourism;(4)Tourism has an enhancing effect on personal mental health,and the enhancing effect is most significant among the middle-aged and young people who are unmarried and do not have children *** results have been reasonably analyzed and explained,and relevant suggestions are put forward.

关键词： Tourism mental health factor analysis structural equation model enhancement

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Analyze the Performance of Electroactive Anticorrosion Coating of Medical Magnesium Alloy Using Deep Learning

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Computers, Materials & Continua 2024年第4期79卷 263-278页

作者： Yashan feng Yafang tian Yongxin Yang Yufang Zhang Haiwei Guo Jing’an Li Advanced Functional Materials Laboratory Zhengzhou Railway Vocational and Technical CollegeZhengzhou450000China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450000China

Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion protection.A first-time proposal, the total acidity (TA) potential of the hydrogen (pH) concept significantly shapes medicalmagnesium alloys. These coatings are meticulously designed for robust corrosion resistance, blending theoreticalinsights and practical applications to enhance our grasp of corrosion prevention mechanisms and establisha systematic approach to coating design. The groundbreaking significance of this study lies in its innovativeintegration of the TA/pH concept,which encompasses the TA/pH ratio of the chemical environment. This approachsurpasses convention by acknowledging the intricate interplay between the acidity and pH levels within thecoating formulation, thereby optimizing metal-phosphate-based conversion coatings and transforming corrosionmitigation strategies. To authenticate the TA/pH concept, the study comprehensively compares its findings withexisting research, rigorously validating the theoretical framework and reinforcing the correlates among TA/pHvalues and observed corrosion resistance in the coatings. The influence of mutations that occur naturally inthe detergent solution on persistent phosphorus changes is shown by empirical confirmation, which improvescorrosion resistance. This realization advances the field ofmaterials and the field’s knowledge of coated generation,particularly anticorrosion converter layers.

关键词： Medical magnesium alloys hydrogen gas anticorrosion total acidity potential of the hydrogen(pH)

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Deformation of Rigid Conjugate Self-dual Galois Representations

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1599-1644页

作者： Yi feng LIU Yi Chao tian Liang XIAO Wei ZHANG Xin Wen ZHU Institute for Advanced Study in Mathematics Zhejiang UniversityHangzhou 310058P.R.China Morningside Center of Mathematics AMSSChinese Academy of SciencesBeijing 100190P.R.China New Cornerstone Lab Beijing International Center for Mathematical ResearchPeking Ui Beijing 100871P.R.China Department of Mathematics Massachusetts Institute of TechnologyCambridge MA 02139United States Department of Mathematics Stanford UniversityStanfordCA 94305United States

In this article,we study deformations of conjugate self-dual Galois *** study is ***,we prove an R=T type theorem for a conjugate self-dual Galois representation with coefficients in a finite field,satisfying a certain property called ***,we study the rigidity property for the family of residue Galois representations attached to a symmetric power of an elliptic curve,as well as to a regular algebraic conjugate self-dual cuspidal representation.

关键词： Galois deformation rigid conjugate self-dual Galois representations

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