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Offload Strategy for Edge Computing in Satellite Networks Based on Software Defined Network

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Computers, Materials & Continua 2025年第1期82卷 863-879页

作者： Zhiguo Liu Yuqing Gui Lin Wang Yingru Jiang Communication and Network Laboratory Dalian UniversityDalian116622China college of environment and Chemical Engineering Dalian UniversityDalian116622China

Satellite edge computing has garnered significant attention from researchers;however,processing a large volume of tasks within multi-node satellite networks still poses considerable *** sharp increase in user demand for latency-sensitive tasks has inevitably led to offloading bottlenecks and insufficient computational capacity on individual satellite edge servers,making it necessary to implement effective task offloading scheduling to enhance user *** this paper,we propose a priority-based task scheduling strategy based on a Software-Defined Network(SDN)framework for satellite-terrestrial integrated networks,which clarifies the execution order of tasks based on their ***,we apply a Dueling-Double Deep Q-Network(DDQN)algorithm enhanced with prioritized experience replay to derive a computation offloading strategy,improving the experience replay mechanism within the Dueling-DDQN ***,we utilize the Deep Deterministic Policy Gradient(DDPG)algorithm to determine the optimal resource allocation strategy to reduce the processing latency of *** results demonstrate that the proposed d3-DDPG algorithm outperforms other approaches,effectively reducing task processing latency and thus improving user experience and system efficiency.

关键词： Satellite network edge computing task scheduling computing offloading

Experimental Research on a Feasible Building Insulation Material Based Reed in China

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Journal of Thermal Science 2025年第1期34卷 176-187页

作者： LIU Tiantian PENG Yizhe LIU Lifang CAI Chenghan WANG Shuang LI Hongqiang college of Civil Engineering Hunan University college of Civil Engineering Hunan University of Science and Technology School of Energy and Power Jiangsu University of Science and Technology National Center for International Research Collaboration in Building Safety and environment (NCIRCBSE) Hunan University Key Laboratory of Building Safety and Energy Efficiency of the Ministry of Education Hunan University

The seemingly useless reeds are prepared as thermal insulation materials,which not only meet the requirements of environmental sustainability but also enhance the added value of reeds,creating new economic *** hydrophobicity of raw biomass surfaces leads to problems such as weak bonding strength and non-dense structure in the formed materials,as well as issues related to the residual insect infestations on the *** this study,reed straw was used as the raw material,and foamed geopolymer was used as the binder to prepare building insulation materials based *** improve the interfacial adhesion performance between reed straw and foamed geopolymer,a thermochemical modification method-thermal carbonization,was *** this study,the mechanical properties and hydraulic properties of the studied materials with different degrees of surface thermal modification were tested,especially the fire resistance performance,and weathering resistance performance rarely found in published *** the surface thermal modification condition of reed straw was 250℃（30 min）,the comprehensive performance of reed-based building insulation materials was the best,when the studied material density was 321.3 kg/m3;the compressive strength was 0.59 MPa;the thermal conductivity was 0.101 W/（m·K）;the pH was 11.27;the moisture absorption rate was 25.1%,and the compressive strength loss rate in wet-dry cycles was 18.5%.In addition,it had excellent fire resistance performance and weathering resistance *** new material can be widely used to improve the thermal insulation of traditional buildings and as sandwich filler in prefabricated buildings,such as preparing insulating walls.

关键词： building insulation material based reed fire resistance performance interface adhesion properties pre-treatment of reeds weathering resistance performance

Universal design of three-dimensional porous graphene-iron based promotors for kinetically rationalized lithium-sulfur chemistry

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Journal of Energy Chemistry 2025年第1期100卷 192-200页

作者： Hua Gao Yunfeng Zhang Menglei Wang Ruoxuan Yang Shuai Feng Xuan Cao Yaping Zhang Zhongyuan Lu Yingze Song State Key Laboratory of environment-Friendly Energy Materials School of Materials and Chemistry Southwest University of Science and Technology School of Material Science and Engineering Henan University of Technology college of Chemistry and Chemical Engineering Taishan University

Lithium-sulfur （Li-S） batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy ***,notorious polysulfide shuttling and retarded sulfur reaction kinetics pose significant obstacles to the further application of Li-S *** rationally designed highly active electrocatalysts can facilitate polysulfide conversion,the universal and scalable synthesis strategies need to be ***,a universal synthetic strategy to construct a series of three-dimensional （3D） porous graphene-iron （3DGr-Fe） based electrocatalysts involving 3DGr-FeP,3DGr-Fe3C,and 3DGr-Fe3Se4is exploited for manipulating the Li-S redox *** has been observed that the implementation of a 3D porous Gr architecture leads to the well-designed conductive networks,while the uniformly dispersed iron nanoparticles introduce an abundance of active sites,fostering the lithium polysulfide conversion,thereby bolstering the overall electrochemical *** Li-S battery with the 3DGr-Fe based electrocatalyst exhibits remarkable capacity retention of 94.8%upon 100 times at 0.2 ***,the soft-packaged Li-S pouch cell based on such a 3DGr-Fe electrocatalyst delivers superior capacity of 1060.71 mA h g-1and guarantees for the continuous 30 min work of fan *** investigation gives comprehensive insights into the design,synthesis,and mechanism of 3DGr-Fe based electrocatalysts with high activity toward efficient and durable Li-S batteries.

关键词： Redox reactions

Thermally triggered topological polymerization in diacetylene-functionalized covalent organic framework toward enhanced memristive properties

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Science China Chemistry 2025年

作者： Panke Zhou Yuxing Huang Ziyue Yu Cong Zhang Qian Chen Yiping Li Chao Lin Xiong Chen State Key Laboratory of Photocatalysis on Energy and environment Key Laboratory of Advanced Carbon-Based Functional MaterialsCollege of Chemistry Fuzhou University

The development of stimuli-responsive switching memory devices and the elucidation of their switching mechanisms in specific environments are crucial for advancing the field of molecular electronics. Herein, we propose two distinct two-dimensional covalent organic frameworks (COFs), namely Py-EDA and Py-BDA, incorporating acetylene (-C≡C-) or diacetylene(-C≡C-C≡C-) moieties, respectively, targeting fabricate memory devices exhibiting stimuli-responsive switching *** findings demonstrate that the incorporation of acetylene units effectively modulates the electronic band structure and enhances the degree ofπ-conjugation, resulting in devices that exhibit typical bipolar nonvolatile memory performance. Notably,upon thermal treatment, the memory behavior of the ITO/Py-BDA/Ag device transitions to a write-once-read-many-times(WORM) mode, displaying decreased SET voltage, increased ON/OFF current ratio, and remarkable retention reliability and cycle stability. This switching behavior is attributed to the occurrence of interlayer solid-state topological polymerization at 350℃, leading to the transformation of diacetylene columnar arrays into enyne chains within Py-BDA, thereby further promoting interlayer charge transfer and separation.

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Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling Liu Biao Meng Tao Chen Yu Han Jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) college of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

Distribution and mapping of temperate savanna in the sandy lands of eastern China

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Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng WANG Tao DUAN Kaijie YANG Bin YANG Chunmei WANG Xin TIAN Qi LU Institute of Ecological Conservation and Restoration Institute of Desertification Studies Chinese Academy of Forestry Institute of Desertification Institute of Desertification Studies Chinese Academy of Forestry Institute of Great Green Wall Satellite Application Centre for Ecology and environment MEE Institute of Microelectronics Chinese Academy of Sciences Aerospace Information Research Institute Chinese Academy of Sciences Institute of Forest resource Information Techniques Chinese Academy of Forestry

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution （VHR） unmanned aerial vehicle （UAV） and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover （FWVC） and fractional herbaceous vegetation cover （FHVC） in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error （RMSE） values for the FWVC and FHVC models were 10.69% and 11.67%,and the R2values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10～6 *** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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InNi alloy-induced interface effect promoting the parallel electron transfer: improved photothermal catalytic CO2 hydrogenation

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Science China Chemistry 2025年

作者： Haoyu Zhang Yuhang Li Yu Nie Xinyu Dou Haodong Ji Xin Tan Jinhua Ye Tao Yu School of Chemical Engineering and Technology Tianjin University Eco-environment and resource Efficiency Research Laboratory School of Environment and Energy Peking University Shenzhen Graduate School School of environmental Science and Engineering Tianjin University Advanced Catalytic Materials Research Center School of Materials Science and Engineering Tianjin University Research Center for Solar Driven Carbon Neutrality Hebei University

Photothermal catalytic CO2hydrogenation is an effective means of utilizing carbon ***,it is severely limited in terms of kinetics and ***,it is necessary to meticulously design catalysts to solve this ***,a sandwich structured NiO@InNi/In2O3is designed to intrinsically regulate the direction of photogenerated carriers transfer,resulting in a CO yield of 42.97 mmol g-1h-1(1290.3μmol h-1) with a selectivity near to 100%.InNi alloy favors the collection of photogenerated carriers by the parallel way and enhancement of the adsorption and activation of *** grown on the surface of InNi alloy not only improves the adsorption of H2and provides sufficient H+for the reaction,but also makes InNi alloy more stable during the reaction *** photothermal effect caused by In2O3accelerates the transfer of photogenerated carriers and increases the surface temperature of the catalyst,thereby synergistically promoting the reaction from a kinetic *** work ameliorates the kinetic and thermodynamic limitations of the photothermal catalytic CO2hydrogenation process through rationally designing the electron transfer direction of the sandwich structured catalysts to parallel way.

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Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng Zhang Chenyang Zhang Linlin Wu Wei Sun Hongliang Zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

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Modeling of acute cadmium toxicity in solution to barley root elongation using biotic ligand model theory

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Journal of environmental Sciences 2016年第4期28卷 112-118页

作者： Xuedong Wang Mingyan Wu Jingxing Ma Xiaolin Chen Luo Hua The Key Lab of resource environment and GIS College of Resource Environment and TourismCapital Normal University

Protons（H^＋）as well as different major and trace elements may inhibit cadmium（Cd）uptake in aquatic organisms and thus alleviate Cd ***,little is known about such interactions in soil *** this study,the independent effects of the cations calcium（Ca^2＋）,magnesium（Mg^2＋）,potassium（K^＋）,H^＋ and zinc（Zn^2＋）on Cd toxicity were investigated with 5-day long barley root elongation tests in nutrient *** tested concentrations of selected cations and trace metal ions were based on the ranges that occur naturally in soil pore *** toxicity of Cd decreased with increasing activity of Ca^2＋,Mg^2＋,H^＋and Zn^2＋,but not K^＋.Accordingly,conditional binding constants were obtained for the binding of Cd^2＋,Ca^2＋,Mg^2＋,H^＋,and Zn^2＋ with the binding ligand：log K（CdBL）5.19,logK（CaBL）2.87,logK（MgBL）2.98,logK（HBL）5.13 and logK（ZnBL）5.42,***,it was calculated that on average 29% of the biotic ligand sites needed to be occupied by Cd to induce a 50% decrease in root *** the estimated constants,a biotic ligand model was successfully developed to predict the Cd toxicity to barley root elongation as a function of solution *** feasibility and accuracy of its application for predicting Cd toxicity in soils were discussed.

关键词： Cadmium Biotic ligand model (BLM) Toxicity Barley

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