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Channel erosion and its impact on environmental flow of riparian habitat in the Middle Yangtze River

Environmental Science and Ecotechnology 2024年第4期20卷 229-236页

作者： Shanshan Deng Junqiang Xia heng Zhu jie Liang Huiwen sun Xin Liu State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China College of Environmental Science and Engineering Hunan UniversityKey Laboratory of Environmental Biology and Pollution Control(Hunan University)Ministry of EducationChangsha410082China

Evaluating environmental flow(EF)is pivotal for conserving and restoring riverine ***,prevalent EF evaluations presume that a river reach's hydraulic conditions are exclusively governed by inflow discharge,presupposing a state of equilibrium in the river *** presumption narrows the scope of EF evaluations in expansive alluvial rivers like the Middle Yangtze River(MYR),characterized by marked channel *** we show the profound channel erosion process and its impact on EF requirements for riparian habitats within the *** research unveils that:(i)pronounced erosion has led to a mean reduction of 1.0-2.7 m in the riverbed across four sub-reaches of the MYR;(ii)notwithstanding a 37-107%increase in minimal discharges post the Three Gorges Project,the lowest river stages at some hydrometric stations diminished owing to bed erosion,signifying a notable transformation in MYR's hydraulic dynamics;(iii)a discernible rightward shift in the correlation curve between the weighted useable area and discharge from 2002 to 2020 in a specific sub-reach of the MYR,instigated by alterations in hydraulic conditions,necessitated an increase of 1500e2600 m^(3)s^(-1)in the required EF for the sub-reach;(iv)it is deduced that macroinvertebrate biomass rapidly decreases as the flow entrains the riverbed substrate,with the maximum survivable velocity for macroinvertebrates being contingent on their entrainment *** findings highlight the importance of incorporating channel morphological changes in devising conservation strategies for the MYR ecosystem.

关键词： Increased environmental flow requirement River bed level lowering Hydraulic condition change Middle Yangtze River

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Heteroatom doping regulates the catalytic performance of singleatom catalyst supported on graphene for ORR

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Nano Research 2024年第3期17卷 1086-1093页

作者： ji-Kai sun Yu-Wei Pan Meng-Qian Xu Lei sun Shaolong Zhang Wei-Qiao Deng Dong Zhai Institute of Molecular Sciences and Engineering Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Replacing fossil fuels with fuel cells is a feasible way to reduce global energy shortages and environmental ***,the oxygen reduction reaction(ORR)at the cathode has sluggish kinetics,which limits the development of fuel *** is significant to develop catalysts with high catalytic activity of *** single-atom catalysts(SACs)of Pt supported on heteroatom-doped graphene are potential candidates for *** we studied the SACs of Pt with different heteroatoms doping and screened out Pt-C_(4) and Pt-C_(3)O_(1) structures with only 0.13 V overpotential for ***,it is found that B atoms doping could weaken the adsorption capacity of Pt,while N or O atoms doping could enhance *** regularity was verified on Fe *** the electronic interaction analysis between Pt and adsorbate,we explained the mechanism of this regularity and further proposed a new descriptor named corrected d-band center(ε_(d-corr))to describe *** descriptor is an appropriate reflection of the number of free electrons of the SACs,which could evaluate its adsorption *** work provides a purposeful regulatory strategy for the design of ORR catalysts.

关键词： single-atom catalyst(SAC) oxygen reduction reaction(ORR) heteroatom doping corrected d-band center descriptor

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MOF-derived Se doped MnS/Ti_(3)C_(2)T_(x) as cathode and Zn-Ti_(3)C_(2)T_(x) membrane as anode for rocking-chair zinc-ion battery

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Nano Research 2024年第4期17卷 2781-2789页

作者： Kaisheng sun Zemao Xiao Yunfei Shen heng Lv jianpeng Zhu jianxiang Pang Yang Zheng Wenwen Kong Long Chen School of Chemistry and Chemical Engineering/State Key Laboratory Incubation Base for Green Processing of Chemical Engineering Shihezi UniversityShihezi 832003China CAS Key Laboratory of Functional Materials and Devices for Special Environments Xinjiang Key Laboratory of Electronic Information Materials and DevicesCenter of Materials Science and Optoelectronics EngineeringXinjiang Technical Institute of Physics and Chemistry of CASUrumqi 830011China

Mn-based zinc ion battery has the advantages of low cost and high performance,which makes it the promising energy storage ***,the poor conductivity and the agglomeration in the synthesis process of manganese-based materials restrict the performance of ***,the Se-doped MnS/Ti_(3)C_(2)T_(x)(Se-MnS/Ti_(3)C_(2)T_(x))composite material derived from Mn-based metal-organic framework is *** tests show that Se-doped could generate S defects and enhance the electrochemical activity of *** the same time,the introduction of Ti_(3)C_(2)T_(x) substrate is conducive to exposing more sulfur defects and improving the utilization rate of *** the mechanism study,it is found that Se-MnS/Ti_(3)C_(2)T_(x) is transformed into S/Se co-doped Mn3O_(4) at the first charge,which innovatively elucidated the behavior of S/Se during *** the electrochemical performance test,the specific capacity can reach 74.7 mAh·g^(-1) at 5.0 A·g^(-1).In addition,the Zn-Ti_(3)C_(2)T_(x) membrane electrode is prepared by vacuum filtration as the zinc-poor anode,which is assembled into the rocking chair full battery to avoid dendrite growth and exhibit excellent rate *** addition of Zn2+weakens the electrostatic repulsion between the interlayers of MXene,and the formation of the folded morphology aids the penetration of the *** 1.0 A·g^(-1),the capacity can reach 50.6 mAh·g^(-1).This work is helpful to promote the research and development of the reaction mechanism of manganese based rocking chair batteries.

关键词： rocking-chair zinc-ion battery MnS Zn-Ti_(3)C_(2)T_(x) membrane Se doped Ti_(3)C_(2)T_(x) composite

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A framework of force of information influence and application for C4KISR system

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Journal of Systems Engineering and Electronics 2024年第2期35卷 430-443页

作者： MAO Shaojie DIAO Lianwang sun Yu WANG heng YI Kan XU Xin MAO Xiaobin ZHANG Kecheng Sheng Long Science and Technology on Information Systems Engineering Laboratory The 28th Research Institute of China Electronics Technology Group CorporationNanjing 210007China Unit 94860 of the PLA Nanjing 210008China

The subversive nature of information war lies not only in the information itself, but also in the circulation and application of information. It has always been a challenge to quantitatively analyze the function and effect of information flow through command, control, communications, computer, kill, intelligence,surveillance, reconnaissance (C4KISR) system. In this work, we propose a framework of force of information influence and the methods for calculating the force of information influence between C4KISR nodes of sensing, intelligence processing,decision making and fire attack. Specifically, the basic concept of force of information influence between nodes in C4KISR system is formally proposed and its mathematical definition is provided. Then, based on the information entropy theory, the model of force of information influence between C4KISR system nodes is constructed. Finally, the simulation experiments have been performed under an air defense and attack scenario. The experimental results show that, with the proposed force of information influence framework, we can effectively evaluate the contribution of information circulation through different C4KISR system nodes to the corresponding tasks. Our framework of force of information influence can also serve as an effective tool for the design and dynamic reconfiguration of C4KISR system architecture.

关键词： information warfare command control communications computer kill intelligence surveillance reconnaissance(C4KISR)system information circulation force of information influence information entropy

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Optical grade (Gd_(0.95-x)Lu_(x)Eu_(0.05))_(3)Al_(5)O_(12) ceramics with near-zero optical loss: Effects of Lu^(3+) doping on structural feature, microstructure evolution, and far-red luminescence

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Journal of Advanced Ceramics 2024年第1期13卷 113-123页

作者： Zhigang sun ji-Guang Li Huiyu Qian Yoshio Sakka Tohru SSuzuki Bin Lu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Research Center for Electronic and Optical Materials National Institute for Materials ScienceIbaraki 305-0044Japan Key Laboratory of Photoelectric Detection Materials and Devices of Zhejiang Province Ningbo 315211China

A chemical co-precipitation strategy was employed to synthesize a series of(Gd_(0.95−x)Lu_(x)Eu_(0.05))_(3)Al_(5)O_(12)(x=0.1−0.95)powder phosphors,followed by vacuum sintering to achieve transparent garnet ceramic *** density functional theory indicated Lu_(3)Al_(5)O_(12) was formed in priority compared with Gd_(3)Al_(5)O_(12) during solid-phase *** high-temperature sintering,the Lu^(3+)substitution for Gd^(3+)suppressed point mass diffusion leading to a smaller grain *** in-line transmittances of bulk specimens with x=0.1,0.3,0.5,0.7,and 0.95 nm were~83.5%,80.1%,68.8%,73.7%,and 82.2%at 710 nm(Eu^(3+)emission center),respectively,among which the sample of x=0.1 exhibited the optical grade with near-zero optical loss in agreement with the defect-free single crystal(~100%of the theoretical transmittance).The resulting particle and ceramic materials both presented characteristic Eu^(3+)emission arising from 5D0→7FJ(J=1−4)transition,where the dominant far-red emission at~710 nm arising from ^(5)D_(0)→^(7)F_(4) transition overlapped with the absorption of phytochrome(PFR).The photoluminescence excitation and photoluminescence intensities of(Gd_(0.95−x)Lu_(x)Eu_(0.05))_(3)Al_(5)O_(12) powders and ceramics generally increased at a higher Gd^(3+)/Lu^(3+)***^(3+)dopants delayed the fluorescence lifetime while the bulk samples had shorter lifetime compared to the particle *** transparent(Gd_(0.85)Lu_(0.1)Eu_(0.05))3Al_(5)O_(12) ceramic phosphor exhibited good thermal stability with a high thermal quenching temperature above 533 *** designed ceramic phosphor-converted light-emitting diode had a saturation injection current of 435 mA and a current-dependent color rendering *** importantly,our report marked the developmental stage of transparent ceramic materials towards zero optical loss.

关键词： transparent ceramics garnet phosphors light-emitting diode(LED) optical properties Gibbs free energy

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Effect of post rolling stress on phase transformation behavior of microalloyed dual phase steel

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Journal of Iron and Steel Research International 2024年第3期31卷 688-699页

作者： Wen-quan sun Sheng-yi Yong Tie-heng Yuan Ting-song Yang An-rui He Chao Liu Rui-chun Guo National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing 100083China

The slow phase transformation of microalloyed dual phase steel makes the nonuniform stress and temperature fields during the post rolling cooling process have a significant impact on the phase transformation *** the relatively slow phase transformation of DP780 steel within the microalloyed dual phase steel series,the influence of stress on the phase transformation behavior of DP780 steel was *** quantify the nonuniform thermal and stress conditions in the steel coil,a thermo-mechanical coupled finite element model of the hot-rolled strip cooling process was *** on the simulation data,DP780 steel was chosen as the research material,and Gleeble 3500 thermal simulation equipment was used for experimental *** thermal expansion curves were analyzed through regression to establish the dynamic model of DP780 steel phase transformation under ***,metallographic analysis was conducted to determine phase transformation type and grain size of DP780 *** results confirmed that the stress promotes the occurrence of semi-diffusion-type bainite ***,an appropriate level of stress facilitates the growth of bainitic grains,while the increased stress inhibits the growth of ferritic grains.

关键词： Microalloyed dual phase steel Stress Bainitic transformation Grain Finite element method

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Supramolecular polymer network constructed by a functionalized polyimidazolium salt derived from metal-carbene template approach

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Science China Chemistry 2024年第4期67卷 1224-1228页

作者： Ming-Ming Gan Zi-En Zhang Yi-Fan Zhang heng Zhang Li-Ying sun Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China

In this study,we present a supramolecular templating approach for constructing polyimidazolium salt containing crown ether and cyclobutane *** strategy involves the formation of metal-carbene templates,photochemical cycloaddition,and subsequent demetallation of metal *** by the host-guest chemistry between crown ether units and ammonium salts,we successfully fabricated a supramolecular polymer SPN1,which features imidazolium receptors and cyclobutane *** obtained SPN1 demonstrates outstanding reversible stimulus-response,antibacterial behavior and conductivity.

关键词： metal-carbene template crown ether polyimidazolium salt host-guest chemistry

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First-Principles Studies of Structural Evolutions in Cathode Materials LiMO_(2)(M=Co,Mn,Ni)

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Chinese Physics Letters 2024年第10期41卷 129-136页

作者： Yufeng sun Xin-Gao Gong ji-Hui Yang Key Laboratory for Computational Physical Sciences(MOE) Department of PhysicsFudan UniversityShanghai 200433China Shanghai Qizhi Institution Shanghai 200232China

We explore the structural evolutions of stoichiometric LiMO_(2)using the first-principles calculations combined with the cluster expansion *** automatically obtain the ground state structures of the stoichiometric LiMO_(2)by just considering the cation orderings in the quasi rock-salt structures and the following structural relaxations due to both the atomic size mismatches and the Jahn–Teller *** point out that,on the one hand,the cation orderings are mainly determined by the nearest,the second nearest,and the third nearest cation interactions and can be obtained from the‘phase diagram’we have built using the relative strengths of effective cluster interaction(ECI).On the other hand,the structural relaxations are dominated by the crystal field splitting(CFS)energies,i.e.,structures with larger CFS energies are more *** calculating the ECIs and CFS energies for various structures of LiMO_(2),we clearly show how ECI and CFS play roles in determining the structural evolution mechanism of these systems.

关键词： method. relaxation cluster

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Deep Learning Social Network Access Control Model Based on User Preferences

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 1029-1044页

作者： Fangfang Shan Fuyang Li Zhenyu Wang Peiyu ji Mengyi Wang Huifang sun School of Computer Science Zhongyuan University of TechnologyZhengzhou450007China Henan Key Laboratory of Cyberspace Situation Awareness Zhengzhou450001China

A deep learning access controlmodel based on user preferences is proposed to address the issue of personal privacy leakage in social ***,socialusers andsocialdata entities are extractedfromthe social networkandused to construct homogeneous and heterogeneous ***,a graph neural networkmodel is designed based on user daily social behavior and daily social data to simulate the dissemination and changes of user social preferences and user personal preferences in the social ***,high-order neighbor nodes,hidden neighbor nodes,displayed neighbor nodes,and social data nodes are used to update user nodes to expand the depth and breadth of user ***,a multi-layer attention network is used to classify user nodes in the homogeneous graph into two classes:allow access and deny *** fine-grained access control problem in social networks is transformed into a node classification problem in a graph neural *** model is validated using a dataset and compared with other methods without losing *** model improved accuracy by 2.18%compared to the baseline method GraphSAGE,and improved F1 score by 1.45%compared to the baseline method,verifying the effectiveness of the model.

关键词： Graph neural networks user preferences access control social network

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Activity promotion of Rh_(1)Ca_(x)/Al_(2)O_(3) single-atom catalyst in 1-octene hydroformylation:a volcano curve exists between Ca adding ratio and catalytic activity

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Science China Chemistry 2024年第4期67卷 1187-1192页

作者： Hao Zhang Xingcong Zhang Xilun Wang Qingdi sun Hao Liu Hongbing ji Xiaohui He Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education Fine Chemical Industry Research InstituteSchool of ChemistryIGCMESun Yat-sen UniversityGuangzhou 510275China Huizhou Research Institute Sun Yat-sen UniversityHuizhou 516081China State Key Laboratory Breeding Base of Green-Chemical Synthesis Technology Institute of Green Petroleum Processing and Light Hydrocarbon ConversionCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China

Single-atom catalysts(SACs)are considered the best candidates for olefin hydroformylation due to their combined advantages of homogeneous and heterogeneous *** conventional organo-phosphine modification,Rh SAC is modified by introducing Ca,resulting in a significant increase in activity(maximum~5.7-fold)and ***,a volcano curve between Ca addition ratio and catalytic activity is *** Ca significantly increases activity by decreasing the energy barrier,but excessive Ca decreases activity due to hindering substrate adsorption and reaction.

关键词： hydroformylation bimetallic single-atom catalysts rhodium heterogeneous catalyst

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